Tetrahydrofolate synthetase (to be referred to as C1-THFS hereinafter) is an enzyme which synthesizes a tetrahydrofolic acid derivative that provides C1 group necessary for various metabolic reactions (Non-patent Reference 1; hereinafter, tetrahydrofolic acid is referred to as TF, and tetrahydrofolic acid derivative as TF derivative). Illustratively, TF derivatives give C1 group to the biosynthesis reactions of purine, thymidylic acid histidine, pantothenic acid and the like. That is, TF and TF derivatives are deeply concerned in nucleic acid metabolism, amino acid metabolism and the like. Thus, TF and TF derivatives are found in tissues where cell division is vigorously carried out and essential for cell multiplication and growth.
C1-THFS is a tri-functional enzyme which has 3 types of functions. Illustratively, C1-THFS has the functions of 10-formyl-THF synthetase (EC 6.3.4.3), 5,10-methenyl-THF cyclohydrolase (EC 3.5.4.9) and 5,10-methylene-THF dehydrogenase (EC 1.5.1.5). By exerting these functions, C1-THFS accelerates synthesis of TF derivatives which are necessary for various metabolic reactions.
Analysis of C1-THFS has been carried out using human, mouse, yeast and the like eucaryote, Escherichia coli and the like procaryote and the like various organism species as the object (Non-patent References 2 to 5). Regarding yeast, the presence of a C1-THFS which functions in its cytoplasm and mitochondria is known. Also, regarding human, the presence of a C1-THFS which functions in the cytoplasm of its cells is known.
However, the presence of a C1-THFS which functions in the mitochondria of human cells is not known, and there is only one report of Non-patent Reference 19. In addition, a human C1-THFS gene whose expression is elevated in colon cancer tissue in comparison with normal colon tissue is not known, too.
The references cited in this description are listed in the following.
Non-patent Reference 1
Hum D W et al., The Journal of Biological Chemistry, 1988, vol. 263, no. 31, pp. 15946-15950.
Non-patent Reference 2
Staben, C et al., The Journal of Biological Chemistry, 1984, vol. 261, pp. 4629-4637.
Non-patent Reference 3
Shannon, K. W. et al., The Journal of Biological Chemistry, 1986, vol. 261, pp. 12266-12271.
Non-patent Reference 4
Thigpen, A. E. et al., The Journal of Biological Chemistry, 1990, vol. 265, pp. 7907-7913.
Non-patent Reference 5
Dev, I. K. et al., The Journal of Biological Chemistry, 1978, vol. 253, pp. 4245-4253.
Non-patent Reference 6
Raj S K et al., Biochemistry and Molecular Biology International, vol. 44, no. 1, pp. 89-95.
Non-patent Reference 7
Frohman M. A. et al., Proceedings of The National Academy of Science of The United States of America, 1988, vol. 85, no. 23, pp. 8998-9002.
Non-patent Reference 8
Proceedings of The National Academy of Science of The United States of America, 1977, vol. 74, pp. 5463-5467.
Non-patent Reference 9
Methods in Enzymology, 1980, no. 65, p. 499-.
Non-patent Reference 10
Claros M G et al., European Journal of Biochemistry, 1996, vol. 241, no. 3, pp. 779-786.
Non-patent Reference 11
Kim P J et al., Lancet, 2003, vol. 362, pp. 205-209.
Non-patent Reference 12
R. H. Giles et al., Biochimica et Biophysica Acta, 2003, vol. 1653, pp. 1-24.
Non-patent Reference 13
He T C et al., Science, 1998, vol. 128, pp. 1509-1515.
Non-patent Reference 14
Levens D L, Genes and Development, 2003, no. 17, pp. 1071 1077.
Non-patent Reference 15
Garrow T A et al., The Journal of Biological Chemistry, 1993, vol. 268, pp. 11910-11916.
Non-patent Reference 16
Nikiforov M A et al., Molecular and Cellular Biology, 2002, vol. 22, pp. 5793-5800.
Non-patent Reference 17
Tavtigian S V et al., Molecular Biology of the Cell, 1994, vol. 5, pp. 375-388.
Non-patent Reference 18
Villar E, The Journal of Biological Chemistry, 1985, vol. 260, no. 4, pp. 2245-2252.
Non-patent Reference 19
Prasannan P et al., The Journal of Biological Chemistry, 2003, vol. 278, no. 44, pp. 43178-43187.
Non-patent Reference 20
Sugiura et al., Biochemical and Biophysical Research Communications, 2004, vol. 315, no. 1, pp. 204-211.


The present invention relates to boiling heat transfer surfaces which are provided on a heat exchange wall surface to enhance nucleate boiling and thereby improve the heat transfer action of a boiling liquid such as a halocarbon refrigerant. It is well known that nucleate boiling in a heat transfer apparatus is improved when the heated wall portion through which heat is transmitted from a warm fluid to a boiling liquid has its surface made porous by the formation of cavities in the heated wall portion.
U.S. Pat. No. 3,384,154 teaches that the radii of the cavities provided in the heated wall portion can be controlled by the size of the sintered powder coatings utilized to make the nucleate boiling surface.
U.S. Pat. No. 3,906,604 controls the nucleate boiling cavity size by machining the metal substrate to create protrusions which are frictionally rubbed and stretched to form the cavities.
U.S. Pat. Nos. 3,696,861 and 3,768,290 utilize bent-over tube fins to create elongated nucleate boiling cavities.
German Publication No. 2,510,580 discloses heat pipe surfaces wherein the surface is first mechanically roughened by wire brushing to form close uniform scratches and then electroplated to form nucleate boiling cavities.
U.S. Pat. No. 4,018,264 discloses a boiling heat transfer surface wherein the nucleate boiling cavities are made by electrodepositing copper dendrites on a copper surface at a high current, copper plating the dendrites or nodules and then rolling the dendritic surface to partially compact the nodules.
The present invention relates to a heat transfer surface having improved cavities to promote nucleate boiling; an improved method for preparing such cavities; and an improved method of nucleate boiling which utilizes the improved cavity structures. The present method for preparing the improved nucleate boiling cavities comprises deforming the metal substrate to form indentations in the metal in the form of non-continuous pits or craters and then electrodepositing a metal on the periphery of the pits or craters at a high current density and then at a normal plating current, from a special bath, to provide honeycomb-like surfaces which optimize nucleate boiling augmentation for particular fluids, especially halocarbon refrigerants utilized in refrigerator systems.
The cavity diameters in the plated coatings are directly related to the size of the pits or craters formed on the metal substrate. In the case of sandblasting, the metal deformation is made by grits having a mesh size of 10 to 200. In the case of deforming by knurling, the cavity diameter is determined by the size and number per square inch of the projections on the knurling tool. A pre-plated surface having from 100 to 350 (10,000 to 122,500 per square inch) knurls per inch is preferred in making the present heat exchange surface. It has been found that a knurling tool having 240 knurls per square inch provides pits or craters which, when electroplated, form excellent nucleate boiling cavities in the heated wall surface of a heat exchanger using halocarbon refrigerants such as R-12.
When the heat exchange surface is deformed by sandblasting, silicon carbide of 10-200 mesh, glass beads of 10-200 mesh and ground slag of 60 mesh have been used; silicon carbide of 60 mesh size is preferred for use in R-12.


This invention relates in general to coking devices and in particular to a new and useful apparatus for generating superheated high pressure steam during a dry process of cooling the coke and to an apparatus for carrying out the method.
A method and apparatus for dry cooling incandescent coke are known from German patent application No. P 33 32 702. In this prior art method, the heat from the hot coke is partly transferred in the cooling chamber to a circulated cooling gas and used in a following waste heat boiler and, through a heat exchanger, for generating superheated high-pressure steam. The usual superheater, evaporator, and feed water preheater are provided in the waste heat boiler and connected in series. Experience has shown that the tubes in the superheater are exposed to extreme conditions. On their outside, they are in contact with the hot circulated gases having a temperature in excess of 1,000.degree. C., and inside, they are in contact with the superheated steam flowing therethrough. Also, the reducing atmosphere of the circulating hot gas require very expensive materials which must withstand these extreme temperature as well as high pressures and very corrosive gases.
German OS No. 30 07 040 discloses a method and apparatus for utilizing the sensible heat of coke in a dry cooling process with a circulated inert gas, where the hot circulated gas is directed from the cooling chamber, upstream of the boiler-heat exchanger system, through a combustion chamber into which a fuel gas and an oxygen containing gas, such as combustion air, are introducible. This additional combustion chamber is intended to ensure a continuous steam generation, if irregularities in the hot coke supply occur. In normal operation of the plant, the entire amount of circulating hot has is directed above into the boiler-exchanger system, and the gas first contacts the coils of the superheater.


1. Field of the Invention
This invention relates to a system and method for formatting and displaying numbers, and more particularly, to a system and method for formatting and displaying numbers for use with a hands free telephone in an automobile.
2. Related Art
There are existing systems where a dialed number is parsed and displayed in a designated format. One example of such a system is Lekven et al., U.S. Pat. No. 6,289,226. Another example is Bogart et al., U.S. Pat. No. 5,299,261.
However, these systems are designed to format only telephone numbers and are limited in their ability to format other types of numbers.
In addition, neither of these systems or methods provides a system where voice information, as opposed to dialed or typed digits, is received and formatted. With the increasing use of mobile telephones, especially in motor vehicles, hands free operation of a mobile telephone is becoming increasingly important. In some states, it is illegal to operate a mobile telephone unless a hands free system is used.
There is currently a need for a system that can receive spoken or dictated information and properly format the information without requiring additional instructions or commands. In other words, there is a need for a system that is truly hands free and can function properly without requiring additional manually typed commands.


Technical Field
The present disclosure relates to a vehicle body lower structure of a vehicle such as a car.
Related Art
The vehicle body lower structure of Patent Literature 1 includes front side members which each have a main body portion on the engine room side and a rear portion extending below a vehicle cabin. The rear portion of the front side member is bent obliquely outward and toward the rear of the vehicle and a rear end of the rear portion is coupled to a rocker rail. A reinforcement member extending obliquely inward and toward the rear of the vehicle is coupled to a vehicle inner side surface of a bent portion of the front side member. The rear portion of the front side member and the reinforcement member extend along a floor panel.


Although originally a speaker unit that forms sound by generating wave in the air, the energy for forming sound cannot be effectively converted to sound in the existing speaker unit. In other words, about half of the energy is converted to vibration of the unit itself without becoming a sound thereby causing distortion of sound and dull vibration, and inhibiting an accurate sound formation, which is the object of the unit.
In a speaker system in which the speaker unit is incorporated in an enclosure (speaker box), the enclosure itself similarly vibrates by the vibration of the speaker unit, and such vibration is transmitted to the floor. Generally, the sound becomes difficult to accurately reproduce as the sound becomes lower unless the enclosure is securely fixed to the floor. Thus, if a low sound is emitted at large volume, the entire room may shake by the generated vibration, and the vibration may be transmitted to the adjacent room.


1. Field of the Invention
The present invention relates to a multi-layered circuit substrate for a semiconductor device. Further, the present invention relates to a method of manufacturing the multilayered circuit substrate. Furthermore, the present invention relates to a semiconductor device using such a substrate and a method of producing the same. More particularly, the present invention relates to a multilayered circuit substrate for a semiconductor device having a semiconductor element mounting face on which a plurality of semiconductor elements can be mounted being arranged in the plane direction on one side of the multilayered circuit substrate composed by laminating a plurality of conductor patterns. Further, the present invention relates to a method of producing the multilayered circuit substrate, a semiconductor device, and a method of producing the same.
2. Description of the Related Art
Recently, there has been provided a semiconductor device referred to as a system-in-package (SIP) in which a plurality of semiconductor elements are mounted on one circuit substrate. This semiconductor device will be referred to as “SIP”, hereinafter.
A size of the aforementioned SIP is appropriate to be handled as a chip. An example of SIP is shown in FIGS. 7(a) and 7(b). SIP 100 shown in FIG. 7(a) is composed in such a manner that semiconductor elements 104a, 104b, 104c, the functions of which are different from each other, are mounted in the plane direction on a semiconductor element mounting face formed on one face of a piece of multilayered circuit substrate 102.
As shown in FIG. 7(b), the multilayered circuit substrate 102 forming the above SIP 100 is composed of resin layers 102a, 102b, 102c, 102d which are made of insulating resin, and the conductor patterns 106, 106, . . . and the via holes 108, 108, . . . are formed being laminated on these resin layers 102a, 102b, 102c, 102d.
On one face of the multilayered circuit substrate 102, there are provided connection pads 110, 110, . . . , from which the connecting faces to be connected with the electrode terminals of the semiconductor elements 104a, 104b, 104c are exposed. On the other face of the multilayered circuit substrate 102, there are provided external connection pads 114, 114, . . . , from which the attaching faces on which the solder balls 112, 112, . . . are attached are exposed.
The connection pads 110, 110, . . . and the external connection pads 114, 114, . . . are electrically connected with each other by the conductor patterns 106, 106, . . . and the via holes 108, 108, . . . which are formed and laminated on the resin layers 102a, 102b, 102c, 102d.
One face and the other face of the above multilayered circuit substrate are covered with the protective films 116, 118 made of solder resist except for the connection pads 110, 110, . . . and the external connection pads 114, 114, . . . .
In this connection, the potting resin 120 is filled between the semiconductor element mounting face, which is formed on one face of the multilayered circuit substrate 102, and the semiconductor elements 104a, 104b, 104c mounted on the semiconductor element mounting face.
When SIP 100 shown in FIGS. 7(a) and 7(b) is used, the size of SIP can be reduced to be smaller than the size of a device in which a plurality of semiconductor devices, each semiconductor device having a single semiconductor element, are used. Further, it is possible to reduce a conductor distance between the semiconductor elements 104a, 104b, 104c. Therefore, a signal can be sent and received between the semiconductor elements at high transmission speed.
However, SIP 100 shown in FIGS. 7(a) and 7(b) is composed of a multilayered circuit substrate 102 actually made of resin. Therefore, rigidity of the multilayered circuit substrate 102 is not sufficiently high.
Therefore, the present inventors made investigations into SIP 200 shown in FIGS. 8(a) and 8(b). As shown in FIG. 8(b), the multilayered circuit substrate 202 composing this SIP 200 is formed by laminating the resin layers 202a, 202b made of insulating resin on which conductor patterns 106, 106 . . . and the via holes 108, 108 . . . are formed. On one face of the multilayered circuit substrate 200, there are provided connection pads 110, 110, . . . , from which the connecting faces to be connected with the electrode terminals of the semiconductor elements 104a, 104b, 104c are exposed.
On the other face of the multilayered circuit substrate 202, the metallic plate 204, which is a plate-shaped member having a rigidity higher than that of the multilayered circuit substrate 202, is bonded by the adhesive layer 206 made of insulating resin.
Since metallic plate 204 is joined to the other face of the multilayered circuit substrate 202, SIP 200 and other electronic parts are electrically connected with each other by a lead frame as shown in FIGS. 8(a) and 8(b). Specifically, an end portion of each inner lead 300, 300, . . . of the lead frame is connected with an exposure face of each external connection pad 208, 208, . . . formed along the outer edge of the multilayered circuit substrate 202 by the wire 302.
In this SIP 200, the highly rigid metallic plate 204 is joined to the other face of the multilayered substrate 202. Therefore, rigidity of this SIP 200 is actually enhanced and higher than that of the multilayered circuit substrate 102 made of resin shown in FIGS. 7(a) and 7(b).
However, since the coefficient of thermal expansion of the multilayered circuit substrate 202 actually made of resin and that of the metallic plate 204 are different from each other, stress is generated between them. Cracks tend to be caused on SIP 200 by the thus generated stress.
Since the multilayered circuit substrate 202 shown in FIGS. 8(a) and 8(b) is successively laminated from the resin layer 202a provided on the metallic plate 204 side. Therefore, on a surface of the resin layer 202b laminated on the resin layer 202a, especially on a surface of the resin layer 202b corresponding to the via hole 108 formed on the resin layer 202a, a concave surface, or indentation, tends to be formed as shown in FIG. 9. Therefore, the surface of the resin layer 202b tends to become irregular.
When the connection pad 110 to be connected with the electrode terminal of the semiconductor element is formed on the irregular face of the resin layer 202b as shown in FIG. 9, an exposed face of the connection pad 110 is formed into an irregular face, following the irregular face of the resin layer 202b.
In the case where the exposed face of the connection pad 110 is formed into an irregular face, when a semiconductor element is mounted on a semiconductor element mounting face of the multilayer circuit substrate 202, an electrode terminal of the semiconductor element does not come into contact with the exposed face of the connection pad 110, which causes an imperfect contact and reliability of the finally obtained SIP 200 is deteriorated.
Although the irregular face formed on the resin layer 202b of the multilayer circuit substrate 202 can be flattened by means of polishing, it is necessary to add a polishing process to the conventional manufacturing process of SIP 200, which raises the manufacturing cost of SIP 200. For the above reasons, it is preferable that the semiconductor element mounting face of the multilayered circuit substrate 202 is flattened without adding the polishing process.


Prunus persica.
In a continuing effort to improve the quality of shipping fruits, I, the inventor, typically hybridize a large number of peach, nectarine, plum, apricot, and cherry seedlings each year. The present invention relates to a new and distinct variety of nectarine tree, which has been denominated varietally as xe2x80x98SEPTEMBER BRIGHTxe2x80x99. The present variety was hybridized by me in 1992, grown as a seedling on its own root in my greenhouse, and transplanted to a cultivated area of my experimental orchard at Bradford Farms near Le Grand, Calif. in Merced County (San Joaquin Valley). The variety was developed as a first generation cross using xe2x80x98August Redxe2x80x99 (U.S. Plant Pat. No. 6,363) yellow flesh nectarine as the selected seed parent and an unnamed nectarine as the selected pollen parent. Subsequent to origination of the present variety of nectarine tree, I asexually reproduced it by budding and grafting in the experimental orchard described above, and such reproduction of plant and fruit characteristics were true to the original plant in all respects. The reproduction of the variety included the use of xe2x80x98Nemaguardxe2x80x99 rootstock (unpatented) upon which the present variety was compatible and true to type.
The present variety is similar to its selected seed parent, xe2x80x98August Redxe2x80x99 (U.S. Plant Pat. No. 6,363) nectarine, by producing nectarines that are globose in shape, firm in texture, mostly red in skin color, and yellow in flesh color, but is distinguished therefrom and an improvement thereon by producing fruit that matures about two weeks later.
The present variety is most similar to xe2x80x98September Redxe2x80x99 (U.S. Plant Pat. No. 5,664) nectarine by producing nectarines that are yellow in flesh color and that mature in September, but is distinguished therefrom and an improvement thereon by having a small nonshowy blossom and by producing fruit that is firmer in texture, that has a higher percentage of red skin color, and that is larger in size.


The present invention relates generally to storing information for use in debugging computer software. More particularly, the invention provides a method and apparatus for using a serial bus, such as an IEEE 1394 bus, to remotely create, from a host computer, a snapshot of physical memory of a target computer.
Many operating systems support xe2x80x9ccrash dumpsxe2x80x9d or xe2x80x9ccore dumps.xe2x80x9d These are typically files that an operating system generates when the operating system recognizes an internal failure. Operating systems typically switch to a minimal mode of operation and attempt to save the operating system""s state information to a file on disk. A software developer or system administrator can subsequently use the saved state information to analyze the operating system failure. Such analysis is often referred to as xe2x80x9cdebugging.xe2x80x9d
Typically, a crash dump file is generated by the operating system and stored on a disk drive that is local to the computer on which the internal failure occurred. FIG. 2 is a simplified state diagram showing that upon the occurrence of an internal failure, a state transition 202 occurs from normal operation state 200 to minimal mode of operation state 204 in which a crash dump file is stored locally, for instance on a local hard disk.
Unfortunately, upon the occurrence of an internal failure, for various reasons the operating system may not be able to store the crash dump file locally. For instance, there may be insufficient local storage space available or the target computer""s local hard drive might be off line.
Under such circumstance, it is typically desirable to retrieve the crash dump remotely and store it on a remote computer the moment the target computer crashes. Due to the relatively slow rate at which conventional serial buses transfer data, however, transferring the contents of physical memory of a target computer, for instance 64 megabytes of memory, would take a prohibitively long time.
Accordingly, there is a need for improved techniques for creating a crash dump file much more quickly, while minimizing the amount of operating system state information that is corrupted or otherwise lost, and under circumstances in which a crash dump file cannot be stored on a local drive of the computer that has experienced an internal fault.
Referring to FIG. 3, techniques for remote debugging of the kernel of an operating system and application programs of a first computer, such as target computer 300, from a second computer, such as host computer 302 are known in the art. In such an environment, a hardware link 304 (e.g., RS-232C), such as a serial connection, is used to transmit debugging commands to and return debugging results from software undergoing test on target computer 300, via serial ports 306 and 308. A small portion of core operating system (xe2x80x9cO.S.xe2x80x9d) 310, typically xe2x80x9cpushesxe2x80x9d data to host debugger 312, thus using processor time on target computer 300 and causing side effects on target computer 300 that would not occur absent debugging-related operation of this small portion of core O.S. code.
Kernel debugging presents technical problems different than those presented by debugging application programs 314, which typically run in user mode. For instance, core operating system 310 typically must be halted for kernel debugging, but core operating system 310 typically is not halted for debugging of user mode application programs.
FIG. 4 is a flow chart of simplified steps for conventional remote debugging of core operating system 310, which typically runs in kernel mode. At step 400, a user, such as a system administrator, issues a command through host debugger 312 to break execution, in other words stop, suspend, or halt, execution of target computer 300. At step 402, the system administrator may issue well-known debugging commands to step through portions of code, set the contents of target computer memory locations to specific values, and the like. Debugging in this manner is often a very time-consuming process. At step 404, a determination is made regarding whether the system administrator is finished debugging the core operating system 310 of target computer 300. Steps 402 and 404 continue in a loop until the system administrator is finished remotely debugging the kernel of target system 300, at which point host computer debugger 312 releases control of core 0.S. 310, which may resume executing, as indicated at step 406.
A significant disadvantage of conventional remote kernel debugging in accordance with FIGS. 3 and 4 is that target computer 300 is not operating while the kernel is being remotely debugged. Because debugging is often necessary for certain types of software issues, such as memory leaks, application hangs, and many other non-fatal crashes, and because debugging is typically very time-consuming, there is a need for improved remote kernel debugging techniques that allow debugging to be performed in parallel with operation of a target computer.
A system and method in accordance with certain inventive principles overcomes the foregoing shortcomings of conventional generation of crash dump files and remote kernel debugging. In accordance with principles of the invention, a two-computer crash dump scenario is provided in which a snapshot of the physical memory of a target computer is extracted and stored by a host computer over a serial bus, which may be IEEE 1394 compliant. In this manner, a crash dump can be transferred quickly and under circumstances in which a conventional single computer crash dump may not be feasible.
A host computer debugger may remotely issue a command to stop execution of the core operating system of the target computer. Handshake information is then preferably provided from the target computer core operating system to the host computer debugger. The handshake information preferably specifies, among other information, one or more address ranges at which physical memory is present on the target computer, as disclosed in the commonly assigned patent application entitled xe2x80x9cMethod and Apparatus for Remotely Debugging Computer Software Over a Serial Bus,xe2x80x9d application Ser. No. 09/488,015, filed Jan. 20, 2000, which is incorporated herein by reference.
The host computer debugger then preferably directly accesses the physical memory of the target computer system over the serial bus in accordance with the handshake information. The host computer then stores the contents of the physical memory of the target computer system.
Execution of the core operating system of the target system may then be resumed, and the core operating system of the target computer may be debugged in parallel with resumed execution of the target computer core operating system. In this manner, the amount of time that the target system computer is not operational due to debugging is significantly reduced relative to debugging the core operating system of the target computer in real time.
Additional features and advantages of the invention will be apparent upon reviewing the following detailed description.


The geometries in integrated circuits have scaled to smaller and smaller dimensions. As the geometries have scaled the alignment tolerance of a pattern level to underlying pattern levels has also become smaller and more critical.
In conventional integrated circuit flows, when a pattern such as active, gate, contact, metal, and via is formed on the integrated circuit wafer, alignment marks for alignment in the x-direction and alignment marks for alignment in the y-direction are formed on each of these layers so that subsequent patterns may be aligned using these alignment marks.
Conventional photolithographic alignment is illustrated in FIGS. 1-3. FIG. 1 shows an integrated circuit wafer with multiple integrated circuit chip 20 patterns formed on the wafer. For example, integrated circuit pattern 20 may be the active pattern etched into the integrated circuit wafer. When the active geometries are etched into the integrated circuit wafer active alignment marks 22, 24, 26, and 28 are also etched into the integrated circuit wafer. Typically the alignment marks consist of vertical 40 and horizontal 42 grids as shown in FIG. 3. When another integrated circuit pattern is to be printed on the integrated circuit wafer, it is critical for the new pattern geometries to be properly aligned to the active geometries already etched into the integrated circuit wafer. The reticle 30 illustrated in FIG. 2 may be an integrated circuit gate reticle, an integrated circuit contact reticle, or an integrated circuit implant pattern reticle. A gate reticle is used for illustration. The gate reticle is loaded into a photolithography stepper and the stepper aligns the gate alignment marks 32, 34, 36, and 38 that are on the gate reticle to the active alignment marks 22,24,26,28 that are etched in the integrated circuit wafer. The stepper aligns the gate reticle alignment marks in the x and y directions to the underlying active pattern alignment marks for each of the integrated circuit chips on the wafer. Vertical alignment grids 40 are used for horizontal alignment. Horizontal alignment grids 42 are used for vertical alignment.
An alignment tree for a typical integrated circuit aligns all photoresist pattern alignment marks prior to the contact level to the active x and y alignment marks, aligns the contact pattern alignment marks to the gate x and y alignment marks, aligns the first interconnect pattern alignment marks to the contact x and y alignment marks, aligns via pattern alignment marks to the underlying interconnect x and y alignment marks and aligns interconnect pattern alignment marks to the underlying via x and y alignment marks.
In addition, in order to pattern geometries with a pitch below about 100 nm while using 193 nm lithography, it has become necessary to use double pattern technology (DPT). Using DPT, one interconnect pattern with a pitch of about 100 nm may be split into two patterns each with a pitch of about 200 nm. The interconnect pattern with a 100 nm pitch may then be formed on an integrated circuit wafer by printing both patterns with the looser pitch into the same layer of photoresist.


It is well known within the electronics industry that lead coplanarity is essential to the successful placement of fine-pitch surface mount devices (SMD's). Non-coplanar leads, i.e. those bent up or down with respect to the body of the component, typically result in opens or poor solder joints on the printed circuit board (PCB). It is desirable to reject any components that do not meet coplanarity requirements prior to placement on the printed circuit board. The present industry standards require that all lead tips be coplanar within a 0.004 inch band, forcing inspection equipment to measure coplanarity with .+-.0.002 inch accuracy. Although some non-contact 3-D inspection techniques are capable of providing this degree of accuracy, a number of system constraints prohibit their implementation for this application. These constraints include but are not limited to:
(1) large part sizes,
(2) establishment of a reference (datum) plane,
(3) mechanical space and packaging limitations within the pick and place machine, and
(4) real-time inspection to maintain high pick and place throughput rates.
Other techniques, particularly "implied" techniques based around passive triangulation (i.e. estimation of lead height via measured lead length), have severely limited depth resolution. They may also have other drawbacks such as confusion between lead length error and vertical lead displacement as well as ambiguous polarity information (the inability to differentiate between leads bent up or down with respect to the plane of the part).
It is accordingly an object of the present invention to overcome these constraints while providing the necessary degree of accuracy for proper inspection of lead coplanarity. The optical setup inherent in the disclosed system provides a true, direct measurement of lead height. It produces sufficient depth resolution to measure lead coplanarity to an accuracy of .+-.0.002 inch using conventional sensors and image processing hardware.
An advantage of the disclosed system is its ability to handle a range of SMD components including PQFP, SOIC, PLCC, SOJ, and TapePak with pitch values down to 15 mils. It will accommodate 25-mil pitch parts up to 1.25 inches square in a single field of view. Parts with a larger number of leads or finer leads can also be inspected by breaking up the image into multiple fields of view, typically two or four. If necessary, large fine-pitch devices may be inspected through the use of high resolution image sensors such as line scan or non-RS-170 area cameras, though at present this requires additional complexity for image acquisition.
Other objects and advantages of the present invention will become apparent from the following portion of the specification and from the following drawings which illustrate in accordance with the mandate of the patent statutes a presently preferred embodiment incorporating the principles of the invention.


My new variety of lily plant originated as a seedling which first flowered in 1988 in Boring, Ore. The breeding efforts had as their objective the production of colored, fragrant hybrids between Lilium longiflorum (the Easter lily) and Asiatic lilies, suited to forcing into flower out of season, heretofore unknown in the lily breeding art.
I achieved the desired objective by intercrossing a slightly fertile embryo-cultured seedling from (Lithium longiflorum `Ace`.times.`Sterling Star`) with `Connecticut King.` The seed parent was the diploid form of the Dutch cultivar `Longistar` (unpatented), which had limited commercial distribution in the Netherlands and the United States. This cultivar does not normally produce fertile seed; it can be used in breeding only if its embryos are artificially cultured. The pollen parent, `Connecticut King,` although unpatented, has been extensively cultivated as a commercial cut-flower variety in the United States and the Netherlands. The embryo that produced `Yellow Fashion` was artificially cultured as well.
The flowers of my new lily are characterized by an very large, fragrant, yellow upfacing to slightly outfacing flowers with an "open bell" form with slightly clawed tepals, quite narrow at the base and broadest just below the midpoint of the bud and flower, and with tepal tips flattening but recurving only slightly. This unique flower form is intermediate between the trumpet-form of Lilium longiflorum and the "flat-faced" Asiatic hybrid form with conspicuously recurved tepal tips. The new clone possesses unusually strong, stout stems. In addition, the clone possesses to a high degree desirable characteristics of hybrid vigor. The clone is a good grower and propagator, as observed at Boring, Ore.
My new variety of lily plant has been asexually reproduced by me and under my direction at Boring, Ore. Successive generations produced by natural propagation from bulblets, by bulb scale propagation, and by tissue culturing from bulb scale explants have demonstrated that the novel and distinctive characteristics of my new variety are fixed and hold true under asexual propagation from generation to generation.


The present invention relates to a valve actuating apparatus for an internal combustion engine. More particularly, the invention relates to a valve actuating apparatus which is capable of selectively disabling valves of the engine. This invention finds particular application in motorcycle engines.
To obtain an improved operating efficiency over a wide range of engine speeds, engines have been developed having multiple intake and exhaust valves for each cylinder. For instance, in an engine having two intake and two exhaust valves for each cylinder, for low and medium engine speeds, one of the intake and one of the exhaust valves may be disabled, while all four valves are enabled for higher engine speeds. Of course, a valve actuating apparatus must be provided to selectively actuate the valves.
FIG. 1 shows a cross section of a part of a conventional valve actuating apparatus utilizing an oil pressure actuator 5 for selectively disabling the intake and exhaust valves. In this valve actuating apparatus, a pair of rocker arms 3 and 4 are adjacently mounted on a rocker arm shaft 2, the latter being fixedly mounted to a cylinder head 1. One of the rocker arms 3 is directly driven by a cam shaft, and the other rocker arm 4 is selectively engageable with the rocker arm 3 to thereby selectively enable the valve associated with the rocker arm 4. The actuator 5 is a reciprocation type, constructed such that a shaft pin 5a slidably mounted in the rocker arm 3 is pushed by pressurized oil to protrude into the rocker arm 4. A pressure oil chamber 5b receiving the shift pin 5a is communicated through an oil path 5c with an oil path 5d provided in the rocker arm shaft 2. An engaging hole 5e sized receiving the shift pin 5a therein is provided at a position of the rocker arm 4 opposing the pressure oil chamber 5b. There is provided in the engaging hole 5e a return pin 5f for urging the shift pin 5a back into the pressure oil chamber 5b and an elastic member 5g for urging the return pin 5f toward the rocker arm 3.
In operation, when the engine is driven at a high speed, operating oil at a predetermined pressure is supplied into the oil path 5d from an oil supply apparatus (not shown) to thereby energize the actuator and couple the rocker arms 3 and 4.
In most conventional actuator systems, oil paths are provided in members adjacent to the actuator (the rocker arm 3 and the rocker arm shaft 2, etc. in the abovedescribed actuator) to provide paths for supplying operating oil as lubricating oil for other engine components. Specifically, interlinked portions of the members forming the oil paths and the sliding portion of the actuator are constructed so as to allow the operating oil to be leaked slightly therefrom.
If the engine has been operated at a low speed for a long period, and hence the actuator is not supplied with operating oil for a long period, air tends to leak into the oil paths from the sliding and the interlinked portions. If the air leaked into the oil paths remains until the actuator is activated, the responsiveness of the actuator may be low. Namely, in the above-described valve actuating apparatus, for example, the moving speed of the shift pin 5a is made lower so that the edge portion of the shift pin 5a is likely to collide with the edge portion of the inlet of the engaging hole 5e thus making it difficult to smoothly activate the actuator to couple the rocker arm 4 to the rocker arm 3.
To overcome this drawback, it has been proposed to provide an oil pump for exclusive use by the actuator adjacent to the actuator so as to shorten the time required for the operating oil to reach the actuator from the oil pump. However, in this case, the size of the engine is unavoidably increased due to the provision of the oil pump near the actuator, and further a transmission mechanism for exclusive use for driving the oil pump is required, thereby making the oil supply apparatus expensive.
A typical example of the conventional valve actuating apparatus installed on an engine is shown in FIG. 3. There is provided, in a cylinder head a at the top of the engine disposed almost at the center of a body having a front and a rear wheel, a valve actuator d operated by pressurized oil and having an oil pressure chamber c. Operating oil is supplied to the oil pressure chamber c from a control valve b, whereby the intake and exhaust valves e of the engine are selectively activated. The conventional control valve includes a spool valve j for selectively opening a control path f, an oil supply path g and an oil return path h provided in a valve housing i having a control path communicating with the oil pressure chamber c. The oil supply path g communicates with an oil pressure source and the oil exhaust path h communicates with an oil ejecting opening.
In this type of control valve, the height of an opening end of the oil exhaust path h, that is, the height of the oil ejecting opening, is of particular importance. If the oil ejecting opening is disposed relatively lower, the oil in the path h is likely to undesirably flow out through the oil ejecting opening, while if it is disposed relatively higher, the resistance of the oil path from the control path to the oil ejecting opening becomes higher so that the responsiveness of the control apparatus is lowered. Further, the control valve must be positioned by taking into consideration the tilt angle thereof when the motorcycle is held up by its kickstand.
The control valve b is generally disposed along a horizontal line parallel to the crankshaft of the engine in the valve casing i as shown in FIG. 3. Thus, the control valve b is subjected to the vibration of the engine, which may cause the state of the control valve b to change states unintentionally. Namely, for example, a four-cycle, four-cylinder in-line engine generally vibrates not only in a vertical direction, but also in a horizontal direction (the direction parallel to the crankshaft) with an amplitude almost half that in the vertical direction. In order to prevent such erroneous changeover operations of the intake and exhaust valves, it has been unfavorably required to increase the elasticity of a spring or the magnetic force of an operating solenoid associated with the control valve.


With development of display technology, liquid crystal displays have become most commonly used display devices.
In the process of manufacturing a liquid crystal display, the cell process, as an important procedure, comprises not only aligning and then assembling an array substrate and a color filter substrate, but also irradiating the frame glue filled between the array substrate and the color filter substrate by using ultraviolet light so as to solidify the glue. Since the electrical performance of the thin film transistor (TFT) provided on the array substrate will be affected after ultraviolet irradiation, those parts where the TFT and the like are located should be covered with an ultraviolet mask plate during the irradiation, but leaving the frame glue exposed.
An existing ultraviolet mask plate, comprising a glass substrate and a layer of shielding metal formed on the glass substrate, is also prepared by using a mask plate through a patterning process. Since the ultraviolet mask plate can be reused, the usage rate of the mask plate for manufacturing the ultraviolet mask plate is rather low. Hence, the cost of manufacturing the ultraviolet mask plate is relatively high in the prior art.


A router is a device that forwards traffic between networks. Routers use headers and a forwarding table to determine where packets go, and they use messaging such as the Border Gateway Protocol (BGP) to communicate with each other and configure the best route between any two hosts.
Conventional routers include a packet forwarding component and a route processor (RP). The RP determines and controls configuration, security, accounting, debugging, and network management processes of the packet-forwarding component. Examples of route processors include the Cisco® CSC/3 and the CSC/4 route processors. Route processors are typically implemented on an electronic printed circuit board.
The RP typically has relatively more processing and resource requirements than the packet-forwarding component. As the traffic between networks increases, router capacity must also increase. This places an even greater processing demand on the RP. The RP can, therefore, become a “bottleneck” as processing in the router is slowed by inadequate processing capability within the RP.
One solution for meeting the increased processing demands on the RP is to distribute the RP function across two or more loosely coupled processors. A problem with this approach is how to direct locally addressed packets to the appropriate RP out of the two or more distributed route processors. Another problem is how to reassemble fragments in an RP distributed across two or more processors.
For the reasons stated above, and for other reasons stated below which will become apparent to those skilled in the art upon reading and understanding the present specification, there is a need in the art for a system and method for routing packets within routers having distributed route processors.


Wearable personal ornamental items are widely popular in cultures throughout the world. Such items include, for instance but not limited to, watches, bracelets, and rings. Rings are widely worn ornaments used to decorate, for example, fingers and toes. Rings may be designed to fit a finger differently. For instance, “regular fit” bands include a flat interior. U.S. Pat. No. 6,166,053, to Seibenberg, reports “comfort fit” bands including a curved interior as reported in and shown in FIG. 2 therein. A ring interior including an annular circumferential groove is reported by U.S. Pat. No. 6,701,618, to Gefen.
Methods of fabricating rings and other jewelry items are known to those skilled in the art, and are set forth, for instance, in “The AJM Guide to Lost-Wax Casting” (MJSA/AJM Press); Mulock, J., “Cast-A-Way: The Complete Lost Wax Process for the Amateur or Professional Jeweler”; Romanoff, P., “The Complete Handbook of Centrifugal Casting”; and Romanoff, P., “The Art and Science of Centrifugal Casting Metal.”
Use of gemstones, enameling, engraving, and finishing techniques in jewelry has also been described. Gemstone-setting techniques are described in Wooding, R. R., “Diamond Setting Manual: Procedures and Techniques”; Wooding, R. R., “Diamond-Setting: The Professional Approach”; Wooding, R. R., “Bead Setting Diamonds with Pave Applications”; and Wooding, R. R., “Channel Setting Diamonds with Illustrated Procedures.” Jewelry finishing is described, for example, in Hoch, “Tumble Finishing for Handmade Jewelry.” Engraving of jewelry is described, for example, in Meek, J. B., “The Art of Engraving.” Electroplating and electroforming techniques are described, for example, in “Midas® Plating Guide,” Third Edition, produced by Rio Grande. Enameling techniques are described, for example, in McGrath, J., “First Steps in Enameling”; Werge-Hartley, J., “Enamelling on Precious Metals”; Cohen, K. L., “The Art of Fine Enameling”; and Matthews, G. L., “Enamels, Enameling, Enamelists.” Jewelry may also be constructed by die-striking or stamping, as discussed in McGrath, J., “The Encyclopedia of Jewelry-Making Techniques: A Comprehensive Visual Guide to Traditional and Contemporary Techniques.”
A secure fit is often desirable in a ring to prevent inadvertent loss of the ring. Preferably the fit of the ring is not so secure that the wearer experiences discomfort. Other personal ornament items may be designed to effect different fit characteristics including a secure fit similar to that desirable in a ring. For example, bracelets or watch bands may be constructed to have a snug, or tight, fit.
Although a tight fit may be desirable in a jewelry item, such a fit may cause issues related to ease of use of the jewelry item. For instance, a tightly-fitting ring may be difficult to put on or to remove. Once placed, for example, on a digit or around a wrist or ankle, a tightly-fitting jewelry item may also not be comfortable to the wearer. Previous attempted solutions for increasing the comfort of a tightly-fitting jewelry item, such as those reported by patents mentioned above, may not provide a level of comfort that is entirely satisfactory.
All patents and documents referred to herein are hereby incorporated by reference as if rewritten herein in their entirety.


1. Field of the Invention
The present invention relates to the production of poly(ethylene-2,6-naphthalene dicarboxylates).
2. Discussion of the Background
Poly(ethylene-2,6-naphthalene dicarboxylates) are produced by the polyesterification of dimethyl-2,6-naphthalene dicarboxylate and ethylene glycol in the presence of polycondensation and polyesterification catalyst systems.
In the preparation of dimethyl-2,6-naphthalene dicarboxylate, significant amounts of methyl hydrogen 2,6-naphthalene dicarboxylate are also produced. Consequently, during a typical preparation of poly(ethylene-2,6-naphthalene dicarboxylate) from dimethyl-2,6-naphthalene dicarboxylate, the presence of methyl hydrogen 2,6-naphthalene dicarboxylate inhibits the polycondensation reaction. This inhibition produces a final product that has a lower than desirable inherent viscosity.
There is thus a need for producing a high quality poly(ethylene-2,6-naphthalene dicarboxylate) product from a dimethyl-2,6-naphthalene dicarboxylate starting material contaminated with methyl hydrogen 2,6-naphthalene dicarboxylate.


New communication services and the use of complex waveforms have created a demand for highly linearized power amplifiers. Deviations from linearity are manifest by spectral distortion components in the output of these amplifiers—that is, undesired energy, not contained in the original signal, inside or outside the frequency band of interest. Linearization techniques seek to reduce these distortion components, restoring signal integrity and allowing an amplifier to operate at its best spectral and power efficiency for the specific application.
To date, a number of linearization approaches have been attempted. Most of these techniques, however, are useful only in circumstances where the input signals occupy low-percentage bandwidths (typically 10% or less) or do not change frequency rapidly over time.
For example, existing digital pre-distortion (DPD) techniques, which use non-linear transfer characteristics of an amplifier in order to generate inverse distortion products that can be supplied along with input signals to the amplifier, require time to converge and must have access to the baseband or digital intermediate frequency (IF) signal components (I and Q or IFI and IFQ). Moreover, digital signal processors, ASICS or FPGAs used in DPD-based designs tend to be limited in bandwidth (due to their clock frequencies) and processing capacity.
Current analog pre-distortion techniques are likewise limited in bandwidth and require adjustment when the input signal center frequency is changed. Adaptive linearization can eliminate the limitations to the change in the center frequency of these designs, but tend to be slow to respond to changes in system characteristics and can be very complex to implement.
Feed-forward linearization techniques are also complex to implement (often making them unsuitable for use with existing amplifiers), are limited in bandwidth and often do not provide significant gains in efficiency because of the relatively high power consumption of the error or auxiliary amplifier. Other conventional linearization solutions, such as power back-off schemes, envelope elimination and restoration designs, linear amplification using nonlinear components, and Cartesian feedback designs all have their own limitations as well. In addition, the increasing complexity of semiconductor-based power amplifiers has memory effect or inertia and therefore limits the use of converging linearization techniques in frequency hopping applications due to the reaction time to correct.


In the past, removal of the access panel or cover to the chassis of an electronic device such as a computer, or the like, was cumbersome or time consuming. In most applications, the access panel is mounted to the chassis using fasteners such as thumb screws, or the like, which must be unscrewed each time the access panel is removed from the chassis. The access panel may then be lifted or slid from the chassis to provide access to components located therein. More recently, quick release latching systems have been provided for securing the access panel to the chassis of the computer. Typically, such latching systems also push the access panel open when the latching mechanism is defeated, making the access panel easier to remove by users.
In modern computer manufacturing facilities, vacuum lifting is often used for lifting the computer to place the computer in packaging prior to delivery. However, when vacuum lifting is employed with a computer chassis that utilizes a quick release latching system that pushes the access panel of the computer open, the access panel can be inadvertently pulled from the chassis of the computer, causing the computer to be dropped and possibly damaged. Generally, this problem occurs because the devices that defeat the latching mechanism are actuated by forces that are applied normal to the access panel during vacuum lifting. The latching mechanism then works in concert with the forces applied during the vacuum lifting process to separate the access panel from the chassis.
Consequently, it would be desirable to provide a quick release latching mechanism that allows the access panel of a computer or similar electronic device to be easily removed from its chassis, but which is not susceptible to inadvertent actuation during processes, such as vacuum lifting, that apply forces to the access panel.


1. Field of the Invention
The present invention relates to an image signal compressing device adapted for use in a facsimile machine and an electronic filing machine.
2. Description of the Prior Art
Recently, a device has been developed which, when used in a facsimile machine or an electronic filing machine, operates to convert an image of intermediate gradation into a binary image signal according to a dither process.
It has, however, been found that, when the binary image signal, converted by the above described device, is compressed according to an MR code or a modified Hoffman (MH), which is a coding (compressing) system standardized in the facsimile machines, the compression ratio tends to be considerably lowered.


Hydroxamic acids are an important class of organic molecules playing a key role in many biologically relevant interactions. Inhibition of matrix metalloproteinases (MMPs) (see Greenwald, R. A.; Golub, L. M., Eds.; Inhibitioin of Matrix Metalloproteinases: Therapeutical Potential; New York Academy of Sciences, vol. 732 (1994), and Rockwell, A.; Melden, M.; Copeland, R. A.; Hardman, K.; Decicco, C. P.; DeGrado, W. F.; J. Am. Chem. Soc., vol. 118 (1996), p. 10337 and references therein) or a unique deacetylase of lipid A biosynthesis (see Onishi, R. H.; Pelak, B. A.; Gerckens, L. S.; Silver, L. L.; Kahan, F. M.; Chen, M-H.; Patchett, A. A.; Galloway, S. M.; Hyland, S. A.; Anderson, M. S.; Raetz C. R. H.; Science, vol. 274 (1996), p. 980) testify to the significance of this class of compounds.
Synthesis on solid support is a crucial technology for combinatorial chemistry efforts. It allows for easy automation of processes and convenient handling of polar molecules throughout the synthetic protocol. It also provides a reliable method for the preparation of mixtures of compounds (split-mix synthesis). The solid supported synthesis of hydroxamic acids, based on Wang, Sasrin, or the 2-chlorotrityl O-hydroxylamine bound resin have recently been reported. (See Richter, L. S.; Desai, M. C.; Tetrahedron Lett., vol. 38 (1997), p. 321; Gordeev, M. F.; Hui, H. C.; Gordon, E. M.; Patel, D. V.; Tetrahedron Lett., vol. 38 (1997), p. 1729; Mellor, S. L.; McGuire, C.; Chan, W. C.; Tetrahedron Lett., vol. 38 (1997), p. 3311; and Bauer, U.; Ho, W-B.; Koskinen, A. M. P.; Tetrahedron Lett., vol. 38 (1997), p. 7233.) Another alternative synthetic approach, based on resin N-linked hydroxylamine has been reported. (See Ngu, K.; Patel, D. V.; J. Org. Chem., vol. 62 (1997), p. 7088.)
We have found two major limitations of the reported methods for making hydroxamic acids using solid-support resins. First, during side chain modifications we sometimes observed undesired functionalization of the nitrogen which ultimately is part of the hydroxylamino moiety of the hydroxamic acid: Resin-ONHCOR. Second, none of the above reported methods allows application of acid labile protecting groups (e.g. Boc) during side-chain synthesis.


Subsea is a well-known term used to refer to equipment, methods and technology used at underwater locations, and particularly at locations on or close to the seabed for various applications, and in particular to explore, drill and develop oil and gas fields that exist below the ocean floors. The ocean floor or seabed at which subsea apparatus is used may be at a relatively shallow location (shallow in this context being at depths less than 1,000 feet) or at a deep water location (generally meaning water depths in the range 1,000 to 10,000 feet, or even deeper).
It will be appreciated that a wide variety of types of subsea apparatus (equipment) is used in such applications. This variety includes subsea apparatus providing a control function (for example comprising controllable valves to regulate the flow of fluids to or from a well) and subsea apparatus providing a connection function (such as providing an electrical or optical control or monitoring link between two pieces of apparatus, or providing a fluid conduit from one subsea location to another, for example to convey fluids to a well for injection into that well, or to convey production fluids from a well). A term commonly used to refer to one type of such subsea interconnecting apparatus is “umbilical”, and a subsea umbilical will typically comprise a flexible intermediate portion containing at least one electrical cable, optical wave guide, or fluid conduit, with connection means provided generally at each end for connecting the umbilical to other apparatus. For example, umbilicals are known which comprise a plurality of electrical conductors (e.g. wires or cables) with a corresponding plurality of electrical contacts provided in connectors at each end of the umbilical. There are circumstances in which such an umbilical, or indeed another piece of subsea apparatus, is conveyed to a subsea (underwater) location (this operation is also referred to in the art as “deploying” the apparatus) and is required to remain at that location for some time before it is installed (i.e. connected to some other piece of subsea equipment). For example, an umbilical for providing fluid, electrical and perhaps optical connection to a well head may first be laid on the seabed (deployed). Then, an end of the umbilical may be placed into a mechanical receptacle on the well head to provide the fluid connection (and in this condition the umbilical is partially installed). In certain known arrangements the electrical and/or optical connection between the umbilical and well head is provided by connecting another piece of subsea apparatus, known as a “jumper”, between a connector on the umbilical and a corresponding connector on the well head. Thus the jumper is another form of subsea interconnect apparatus or device, typical shorter than apparatus referred to as umbilicals, but similarly providing an interconnecting function. When the jumper is connected, the umbilical is then fully installed to the well head. Clearly, although a subsea umbilical or other subsea apparatus can be tested before it is deployed (i.e. before it is conveyed to its subsea location), degradation or damage to it may occur while it is being transported to its deployment location and indeed while it is waiting at that location before installation occurs. For example, if the connectors of subsea apparatus are not protected in some way at the subsea location before installation, then they can in general become contaminated with silt or other material, and any electrical contacts they contain could suffer corrosion. Such degradation is problematic. One attempt to solve these problems has been to fit a so-called “dummy” connector to the connector of subsea apparatus such as an umbilical, the dummy connector mating with the apparatus's connector in the same way as would a corresponding connector of apparatus to which the umbilical is to be connected. Certain known arrangements are such that when the connector and dummy connector are mated at least one seal is made which prevents or at least inhibits the ingress of contaminants into the mated arrangement and prevents seawater from making contact with any electrical contact of the umbilical's connector. Certain dummy connectors are adapted to provide protection to other parts of the connection interface (i.e. not just to electrical contacts). The dummy connector typically remains mated with the connector of the subsea apparatus until shortly before that apparatus is to be installed. The dummy connector is then detached and the subsea apparatus is connected in the required configuration. Although this technique offers some advantages, there is still the possibility that the subsea apparatus could have been damaged or degraded in some way while the dummy connector was in place. For example, although the dummy connector may have protected the connector of an umbilical, the umbilical may have suffered damage elsewhere along its length whilst in situ or waiting for deployment. Only after removal of the dummy connector, and connection of the umbilical to other subsea apparatus may this damage or degradation become apparent, when a problem is detected with the operation of the subsea system as a whole.
It is therefore an object of certain embodiments of the invention to provide subsea assemblies, subsea test apparatus and methods of handling subsea apparatus which overcome, at least partially, one or more of the problems associated with the prior art.


As is generally known in the field of semiconductor memory devices and other semiconductor integrated circuits, it is often required to generate internally voltages that are greater than an external voltages, also known as off-chip power supply voltages. For example, it is known in flash electrically erasable, programmable read-only memories (EEPROMs) that a first high voltage of about +5V is needed to be produced for the read mode of operation of memory cells. Also, a second high voltage of about +10V is needed to be produced for the program mode of operation of the flash memory cells. To meet this requirement, the semiconductor memories also generally include one or more internal voltage boosting circuits for generating output signals boosted to be higher than an external supply voltage.
In FIG. 1, there is shown a simplified block diagram of a conventional voltage boosting circuit 10 for generating a word line voltage VPP, which is passed to appropriate word lines WL0 through WLn in a memory cell array via respective row decoder circuits 20. The voltage boosting circuit 10 includes a high voltage charge pump circuit 14 which is used during the program mode of operation of the semiconductor memory devices. The charge pump circuit 14 serves to charge up the word line voltage VPP at the internal word line supply node N1 to approximately 10V when the enable signal ENVPP is high. The boosting circuit 10 also includes a precharge logic circuit 12 which functions to precharge the word line voltage VPP to the external power supply voltage VCC, before the node N1 is boosted or pumped to a high voltage. The precharge logic circuit 12 will also maintain the supply voltage VPP equal to the external power supply voltage VCC in other modes of operation via the PMOS transistor P1. The capacitor C.sub.L represents the capacitive loading of the row decoder circuits 20, plus all of the parasitic capacitance associated with the line 2 connected to the word line supply node N1.
With reference to FIGS. 2(a) through 2(e), the operation of the voltage boosting circuit 10 depicted in FIG. 1 will now be explained. Initially, it is assumed that prior to time t1 the enable signal ENVPP and the precharge bar signal PRECHARGEB are both low (VSS), and that kick bar signal KICKB is high (VCC). Thus, the output of the NAND gate 18 on the line 3, defining the kick voltage VKICK, will be low (VSS). Further, the word line voltage VPP at the supply node N1 will be at the power supply voltage VCC, since the PMOS transistor P1 will be turned on.
When the kick bar signal KICKB makes a high-to-low transition at the time t1 as shown in FIG. 2(a), the precharge bar signal PRECHARGEB in FIG. 2 will be pulled to the power supply voltage VCC at time t2. At time t3, the kick voltage VKICK will begin making a low-to-high transition, as depicted in FIG. 2(b). This will, in turn, cause the word line voltage VPP at the supply node N1 to be raised or boosted by the kick signal VKICK via the booster capacitor C.sub.BOOST, from an initial value of VPPinit=VCC, to a boosted level VPP.sub.BOOST, starting at the time t3 in FIG. 2(d). As a result, the precharge bar signal PRECHARGEB will be further raised to the boosted level at time t4 as shown in FIG. 2(c).
This boosted level of the word line voltage VPP.sub.BOOST can be calculated from the following equation: ##EQU1## Where: EQU VKICK=Power supply potential VCC (2) EQU VPP.sub.init =Power supply potential VCC (3)
and C.sub.BOOST, C.sub.L are respectively the capacitances of capacitors C.sub.BOOST, C.sub.L. By substituting the equations (2) and (3) into the equation (1) and simplifying, there is given: ##EQU2##
From above equation (4), it can be seen that if the required maximum for the word line voltage VPP is less than the level that can be generated by the voltage boosting circuit 10 of FIG. 1, then the conventional boosting circuit 10 will be able to operate adequately. Unfortunately, as previously pointed out, the word line voltage VPP is typically required to be pumped up to approximately +10V for the program mode of operation of the flash memory cells. Therefore, under these circumstances, an additional means is required for producing this higher voltage, such as a second higher voltage charge pump.
However, the use of the conventional voltage boosting circuit 10 for this purpose is impractical, since the total capacitance that is seen by the high voltage charge pump 14 is very high, which is because the boost capacitor 15 is constantly connected to the kick signal VKICK, which is at a value of either VCC or VSS. As a result, this conventional voltage boosting circuit 10 suffers from the disadvantage that either the charge pump 14 would require a much longer time in order to raise the voltage VPP to the necessary programming level, or the size of the charge pump 14 must be increased, so as to raise the voltage VPP to the necessary programming level in the same amount of time. The first way would increase the programming time, and the second way would increase the cost and complexity of the overall memory device. Thus, neither of these choices offers a satisfactory solution.
More specifically, this problem of the conventional circuit 10 having a high total capacitance can be illustrated by referring back to equation (2) above. If we let VPPmin be equal to the minimum VPP supply voltage required for the read mode of operation for a flash memory cell, and let VCCmin be equal to the minimum VCC power supply voltage of the flash memory cell, then we have through substitution: ##EQU3##
Further, by assuming VPP.sub.min to be equal to +4.2V and VCC.sub.min to be equal to +2.5V, there is given: ##EQU4##
By solving for the booster capacitor C.sub.BOOST, there is given: C.sub.BOOST =2.125C.sub.L. Therefore, the total capacitance C.sub.TOTAL has been shown to have increased due to the booster capacitor: C.sub.TOTAL =C.sub.BOOST +C.sub.L or =3.125C.sub.L.
Accordingly, it would be desirable to provide an improved voltage booster circuit which overcomes the disadvantages of the conventional case, so as to be capable of operating efficiently and effectively in a low supply voltage environment. It would be expedient that the voltage booster circuit be operated effectively so as to produce a significant reduction in power dissipation.


The present invention is directed toward optical communication system. In particular, optical communication systems providing dispersion slope compensation.
Optical signals transmitted in a fiber optic communication system typically constitute a series of pulses of digital information. Although the pulses are usually at a single nominal wavelength, each pulse is actually composed of different spectral components. These spectral components propagate through the transmission fiber at different speeds with higher frequency components traveling slower than lower frequency components. This effect, known as xe2x80x9cchromatic dispersionxe2x80x9d, can result in spectral components of one pulse arriving at a receiver at substantially the same time as a succeeding pulse, thereby causing degraded receiver sensitivity. Chromatic dispersion becomes increasingly pronounced at higher bit rates, e.g. 10 Gbit/sec. such as those associated with synchronous optical network (SONET) OC192 transmission speeds. Unique fibers have been developed to offset or compensate chromatic dispersion. These fibers, referred to as dispersion compensated fiber or DCF, are commercially available from Corning Inc. and Lucent Technologies, for example. DCF fibers are typically specified with a dispersion coefficient having an opposite sign to that of the transmission fiber. The net dispersion experienced by the transmitted optical signal is thus the sum of the dispersion accumulated through the transmission fiber and the DCF. If the product of dispersion coefficient times length in the DCF is equal in magnitude and opposite in sign to that of the transmission fiber, the net dispersion is zero, and the dispersion is said to be compensated.
DCF typically provides compensation at a particular wavelength. As a result, single wavelength optical transmission systems incorporating DCF and operating at the specified wavelength can have relatively low error rates, even at OC192 transmission speeds.
In order to further increase fiber capacity, wavelength division multiplexed (WDM) systems have been developed for carrying multiple wavelengths on a single fiber. At OC192 rates, each wavelength or channel of a WDM system must be dispersion compensated. Typically, the dispersion coefficient of the transmission fiber, as well as that associated with DCF, varies with wavelength; the relationship of dispersion and wavelength being referred to xe2x80x9cdispersion slopexe2x80x9d. Since the dispersion slope associated with the transmission fiber and DCF may not be identical, not all channels may be adequately dispersion compensated.
Theoretically, one approach to providing spectrally uniform dispersion compensation involves fabricating DCF uniquely tailored to have a slope of the same magnitude, but opposite sign, as the transmission fiber. As a practical matter, however, such DCF would be difficult to fabricate with precisely the required slope and magnitude.
Alternatively, since the amount of dispersion compensation depends in part on the length of the DCF, varying lengths of DCF can be provided in a WDM system downstream from the point where individual wavelengths have been separated. Each channel can then be compensated individually prior to detection at a photodetector. An additional segment of DCF, however, must be provided for each channel, thereby complicating system design and increasing costs.
Consistent with the present invention, an optical device is provided comprising an optical splitter having an input port and a plurality of output ports, said input port being configured to receive a plurality of optical signals, each at a respective one of a plurality of wavelengths. The optical signals are output from each of the plurality of output ports, but in attenuated form. The optical device further includes a plurality of in-fiber Bragg gratings, each of which being coupled to a respective one of the plurality of output ports. The in-fiber Bragg gratings are configured to reflect a selected one of the plurality of optical signals and compensate for a dispersion associated with the selected one of the plurality of optical signals.


There are many reasons to encode an inaudible message in audio data and many groups would like to have access to such technology. A group with such an interest is the group of copyright owners. Copyright owners would like such an encoding technique to facilitate copyright enforcement and protection. Copyright enforcement would be facilitated by encoding pieces of copyrighted works with a watermark to provide ownership information for copyright enforcement. Alternatively, the copyrights of a work may be protected by a copy protection scheme, e.g. encryption keys encoded onto the audio data, which would prevent unauthorized use of the protected matter.
Another group with an interest in using inaudible messages encoded into audio data would be the group of audio listeners. The encoding would provide listeners with useful information about the programs they are listening to without affecting the audio experience. For example, the names of the performers, the name of the performance, or the name of the broadcaster may be given and relayed to the listener via the listener's receiver.
Still another group with an interest in the encoding of inaudible messages into audio data would be market researchers who make use of audience estimating techniques, as well as customer loyalty programs, commercial verification functionality and program identification. Inaudible messages encoded into broadcast or recorded audio are particularly useful in implementing such techniques and activities.
Yet still another group with an interest in the encoding of inaudible messages into audio data would be those seeking additional bandwidth to communicate data that is totally unrelated to the audio data. For example, telecommunications companies could utilize the bandwidth to carry their data and/or news organizations could relay real time news such as breaking headlines or stock quotes.
There are many other good reasons that other interested groups have for the encoding of inaudible messages into audio data. One problem encounterd in attempting to encode multiple messages inaudibly within audio data is that there is only a limited amount of bandwidth available for this purpose.
The limited bandwidth is due to the fact that audio data can only receive a finite amount of energy in the encoding process before the encoding becomes audible. This level of acceptable ancillary data energy in audio data is application dependent. For example, in high fidelity applications such as music distribution or broadcasting, the messages must be keep inaudible. However, in certain other applications such as voice data communication, e.g. cell phone communications, the constraints on the amount of acceptable ancillary data energy in the audio data are less rigorous. The bandwidth limitations due to these constraints are further restricted by the administrative load imposed by error detection and correction data, marker data, sync data, address data and the like.
A further problem arises in applications requiring the encoding of one or more messages in audio data that is already encoded with another message. This is desired in certain broadcast and recording applications, such as audience measurement, commercial and network clearance, and content identification. It has been proposed to reserve different respective time intervals along the time base of the audio data for encoding of plural messages at various levels of distribution (for example, at the production level, the network level and the local affiliate level). Such time division multiplexing of encoded messages substantially restricts bandwidth available for each of the messages and requires a reliable means of determining in each case the permissible time interval for inserting each different message.
Accordingly, what is needed is a way to encode multiple messages inaudibly in audio data in which one or more such messages are encoded in the audio data at different times and/or levels of distribution which achieves desirably high bandwidth and is easily implemented.
It is also desired to provide expanded data communication capability in the limited bandwidth available for ancillary data in an audio channel. It is desired, therefore, to increase the bandwidth afforded by an audio channel to communicate information in the form of ancillary data encoded in the audio data, so that the encoded ancillary data remains inaudible or beneath an acceptable level of audibility when the audio data is reproduced acoustically.


1. Field of the Invention
The present invention relates generally to elements that reroute the locations of bond pads on semiconductor devices and, more specifically, to rerouting elements that are configured to be secured to the active surfaces of fabricated semiconductor devices to reroute the bond pad locations thereof. In addition, the present invention relates to methods for designing rerouting elements and to rerouting methods. The present invention also relates to multi-chip modules with semiconductor devices in stacked arrangement and including one or more of the rerouted semiconductor devices, as well as to methods for forming and packaging such assemblies.
2. Background of Related Art
In order to conserve the amount of surface area, or “real estate,” consumed on a carrier substrate, such as a circuit board, by semiconductor devices connected thereto, various types of increased density packages have been developed. Among these various types of packages is the so-called “multi-chip module” (MCM). Some types of multi-chip modules include assemblies of semiconductor devices that are stacked one on top of another. The amount of surface area on a carrier substrate that may be saved by stacking semiconductor devices is readily apparent-a stack of semiconductor devices consumes roughly the same amount of real estate on a carrier substrate as a single, horizontally oriented semiconductor device or semiconductor device package.
Due to the disparity in processes that are used to form different types of semiconductor devices (e.g., the number and order of various process steps), the incorporation of different types of functionality into a single semiconductor device has proven very difficult to actually reduce to practice. Even in cases where semiconductor devices that carry out multiple functions can be fabricated, multi-chip modules that include semiconductor devices with differing functions (e.g., memory, processing capabilities, etc.) are often much more desirable since the separate semiconductor devices may be fabricated independently and later assembled with one another much more quickly and cost-effectively (e.g., lower production costs due to higher volumes and lower failure rates).
Multi-chip modules may also contain a number of semiconductor devices that perform the same function, effectively combining the functionality of all of the semiconductor devices thereof into a single package.
An example of a conventional, stacked multi-chip module includes a carrier substrate, a first, larger semiconductor device secured to the carrier substrate, and a second, smaller semiconductor device positioned over and secured to the first semiconductor device. Any suitable adhesive may be used to secure the semiconductor devices to one another. The second semiconductor device does not overlie bond pads of the first semiconductor device and, thus, the second semiconductor device does not cover bond wires that electrically connect bond pads of the first semiconductor device to corresponding contacts or terminal pads of the carrier substrate. Such a multi-chip module is disclosed and illustrated in U.S. Pat. No. 6,212,767, issued to Tandy on Apr. 10, 2001 (hereinafter “the '767 Patent”). Due to the use of bond wires to form electrical connections between bond pads and corresponding terminal pads, this type of stacked multi-chip module has been limited to use with semiconductor devices that include peripherally located bond pads.
U.S. Pat. 5,323,060, issued to Fogal et al. on Jun. 21, 1994 (hereinafter “the '060 Patent”) shows one example where dice of the same size are stacked on top of one another over a circuit board. Bonding wires are connected from the bond pads of each die to corresponding terminal pads on the circuit board. In order to provide clearance for the bond wires that electrically connect bond pads and corresponding terminal pads, however, adjacent semiconductor devices must be spaced apart from one another a significant distance.
Stacked multi-chip modules of other configurations have also been developed. For example, it is known that stacked multi-chip modules may include large semiconductor devices positioned over smaller semiconductor devices and that adjacent semiconductor devices may be staggered relative to one another or have different orientations.
Different electrical connection technologies, including wire bonding, tape-automated bonding (“TAB”), and controlled-collapse chip connection (“C-4”), which results in a so-called flip-chip arrangement are but a few of the ways in which discrete conductive elements may be formed in stacked multi-chip modules. Different electrical connection technologies have also been used in single multi-chip modules, with the bond pads of one semiconductor device being electrically connected to corresponding contact areas of a carrier substrate of the multi-chip module with a different type of discrete conductive element than that used to form electrical connections between the bond pads of another semiconductor device and their corresponding contact areas of the carrier substrate.
Many semiconductor devices include bond pads that are arranged at central locations on an active surface thereof Examples include semiconductor devices that are configured for use with leads-over-chip (LOC) type lead frames, in which the bond pads are arranged substantially linearly along the centers thereof, as well as semiconductor devices with bond pads disposed in an “I” arrangement. While it may be desirable to use such semiconductor devices in stacked multi-chip modules, the central bond pad placements thereof do not readily facilitate the use of bond wires or other laterally extending discrete conductive elements to electrically connect the bond pads with their corresponding terminal pads of a circuit board that underlies the semiconductor device stack.
Accordingly, there are needs for apparatus and methods that facilitate the use of semiconductor devices with centrally located bond pads in stacked multi-chip modules. There are also needs for apparatus and methods for reducing the heights of stacked multi-chip modules that include semiconductor devices with peripherally located bond pads.


The present invention relates to a hospital bed. More particularly, the present invention relates to a proning bed which permits rotation of a patient supported on a patient support surface of the bed.
A bed of the present invention illustratively includes a base, and a support assembly coupled to the base. The support assembly includes first and second support arms located above the base. The apparatus also includes a plurality of latch mechanisms coupled to the first and second support arms, and a patient support surface configured to be coupled to the first and second support arms by the plurality of latch mechanisms. The patient support surface is removable from the first and second support arms to permit transfer of a patient to and from the bed on the patient support surface.
In an illustrated embodiment, the support assembly is coupled to a first end of the base. The support assembly includes a rotatable drive mechanism coupled to the first and second support arms for rotating the first and second arms about a longitudinal axis. The first and second support arms may be cantilevered from the support assembly or coupled to a support located at the end of the second base.
A proning surface is configured to be coupled to the first and second support arms. The proning surface is configured to support the patient in a prone position when the patient support assembly is rotated 180xc2x0 about its longitudinal axis by the drive mechanism. In an illustrated embodiment, a plurality of siderails is coupled to the first and second support arms. The siderails each include a portion which is movable over the patient support surface to form a portion of the proning surface.
The illustrated patient support surface includes an outer frame configured to be coupled to the plurality of latch mechanisms to secure the patient support surface to the first and second support arms. The patient support surface also includes a plurality of panels coupled to the outer frame. The panels illustratively include notched portions configured to define handles on the patient support surface. The plurality of panels is pivotably coupled to the outer frame.
The illustrated patient support surface further includes at least one hinge to permit articulation of the patient support surface. The patient support surface includes at least one locking member configured to block pivotal movement of the hinge to hold the patient support surface in a generally planar orientation. The support assembly includes an actuator for selectively releasing the locking member to permit articulation of the patient support surface. In an illustrated embodiment, a latching mechanism is configured to engage each locking member. The actuator is configured to move the latching mechanism relative to the first and second support arms to expose the hinge and permit articulation of the patient support surface.
The illustrated embodiment of the present invention includes a transfer surface coupled to the base. The transfer surface is movable from a lowered position to an elevated position located adjacent the first and second support arms when the patient support surface is coupled to and removed from the first and second support arms. In one embodiment, the transfer surface is configured to engage a portion of the plurality of latch mechanisms as the transfer surface is moved to the elevated position to open the latch mechanisms for receiving the patient support surface.
A line management apparatus of the present invention is configured to be coupled to a patient support surface for routing medical lines and hoses. The apparatus includes a body portion having a top edge. The body portion is formed to include a plurality of notches opening along the top edge to receive the lines and hoses and a plurality of apertures located below the notches for receiving additional lines and hoses. A coupler is coupled to the body portion adjacent to the plurality of apertures. The coupler is configured to connect the body portion to the patient support surface
Additional features of the invention will become apparent to those skilled in the art upon consideration of the following detailed description of illustrated embodiments exemplifying the best mode of carrying out the invention as presently perceived.


This invention relates to a dual optical fiber device and is particularly concerned with a device for transmitting electromagnetic radiation to a radiation sensitive component and receiving output radiation from said component involving a radiation-transmissible junction of optical fibers which provides a substantially unattenuated output radiation signal. The invention also relates to a method for determining a desired parameter which is a function of said output radiation using said device.
The measurement of desired parameters in liquids, particularly in biological systems, is frequently required. For example, the measurement in blood of pH levels and concentration of gases, particularly oxygen and carbon dioxide, is important during surgical procedures, post-operatively, and during hospitalization under intensive care and many devices for the measurement of said physiological parameters have been suggested in the art.
U.S. Pat. No. 4,003,707, Lubbers et al, and its reissue patent Re 31879, disclose a method and an arrangement for measuring the concentration of gases and the pH value of a sample, e.g. blood, involving the use of a fluorescent indicator at the end of a light-conducting cable which is sealingly covered by or embedded in a selectively permeable diffusion membrane. The radiation transmitted to and emitted from the indicator must be passed through various filtering elements and light elements, including reflectors, beam splitters and amplifiers before any meaningful measurements can be made.
U.S. Pat. No. 4,041,932, Fostick, discloses a method whereby blood constituents are monitored by measuring the concentration of gases or fluids collected in an enclosed chamber sealingly attached to a skin "window" formed by removing the stratum corneum over a small area of the patient's skin. The measurements in the enclosed chamber are made, inter alia, by determining the difference in intensity of light emitted from a fluorescent indicator.
U.S. Pat. Nos. 4,200.110 and 4,476,870, Peterson et al, disclose the use of a pH sensitive indicator in conjunction with a fiber optic pH probe. In each of these patents the dye indicator is enclosed within a selectively permeable membrane envelope.
U.S. Pat. No. 4,548,907, Seitz et al, discloses a fluorescent-based optical sensor comprising a membrane immobilized fluorophor secured to one end of a bifurcated fiber optic channel for exposure to the sample to be analyzed.
Many fluorescent indicators sensitive to pH, and thereby useful for pCO.sub.2 measurements, are known in the art. Examples of useful fluorescent indicators are disclosed in the above patents and also in "Practical Fluorescence" by George E. Guilbault, (1973) pages 599-600.
Sensor devices using fluorescent indicators may be used for in vitro or in vivo determinations of components in physiological media. For in vitro determinations the size of the device is normally of no consequence, but for in vivo use, the size of the sensor may be extremely critical and there is an increasing need in the art to miniaturize sensor devices, particularly catheter-type devices, for the in vivo determination of components in physiological media, e.g. blood. However, diminution in size of the components of such devices, particularly in the size of the sensor itself, decreases the strength of the signal emitted by the indicator and consequently presents problems in the detection and measurement of said signal. These problems are aggravated when the detector system requires a multiplicity of components, such as filters, beamsplitters and reflectors to isolate and measure the emitted energy. Each of the said components reduces the emitted signal strength resulting in a sequential loss of measurable signal. Consequently, the more components present in the system, the weaker the final signal strength.
It has now been found that the emission signal from radiation-sensitive indicators, particularly fluorescent indicators of the type disclosed in the references discussed above, may be received substantially unattenuated in a suitable detector without the necessity of filters, beam splitters, reflectors or other light elements used in the prior art if the transmitting optical fiber and emission-receiving optical fiber are coupled in a manner according to the present invention, as described hereinafter.
The elimination of the need for additional optical elements provided by the improved device of the present invention allows greater miniaturization of sensor systems than that attainable in prior art systems without loss of signal strength.


This disclosure relates to the polishing of magnetic, optical, semiconductor and silicon wafers and more particularly, to polishing compositions and methods for polishing and planarizing silicon wafers.
The semiconductor industry uses interconnect metals in forming integrated circuits on semiconductor wafers. These interconnect metals are preferably non-ferrous metals. Suitable examples of such non-ferrous interconnects are aluminum, copper, gold, nickel, and platinum group metals, silver, tungsten and alloys comprising at least one of the foregoing metals. These interconnect metals have a low electrical resistivity. Copper metal interconnects provide excellent conductivity at a low cost. Because copper diffuses into many dielectric materials, such as silicon dioxide or doped versions of silicon dioxide, integrated circuit fabricators typically apply a diffusion barrier layer to prevent the copper diffusion into the dielectric layer. For example, barrier layers for protecting dielectrics include, tantalum, tantalum nitride, silicon nitride, tantalum-silicon nitrides, titanium, titanium nitrides, titanium-silicon nitrides, titanium-titanium nitrides, titanium-tungsten, tungsten, tungsten nitrides and tungsten-silicon nitrides.
In the manufacturing of semiconductor wafers, polishing compositions are used to polish semiconductor substrates after the deposition of the metal interconnect layers. Typically, the polishing process uses a “first-step” slurry specifically designed to rapidly remove the excessive interconnect metal. The polishing process then includes a “second-step” slurry to remove the barrier layer. The second-step slurry selectively removes the barrier layer without adversely impacting the physical structure or electrical properties of the interconnect structure. In addition to this, the second step slurry should also display low erosion for dielectrics.
While the “two-step” slurry generally performs satisfactorily in present conditions, it is desirable to have polishing compositions that can be used for planarizing the metal interconnect without substantial dishing of the interconnect metal and scratching of the wafer surface.
Preparation and evaluation of chemically modified abrasives for chemical mechanical polishing by Partch et al. in an abstract presented at Materials Research Society (MRS) meeting in 2001, discloses coating individual particle cores with a layer of organic or inorganic material. However, Partch et al., disclosed manufacturing the polishing composition with abrasive particles having a large particle size distribution that resulted in scratching and other forms of surface damage.
U.S. Pat. Pub. No. 2004/0060502 to Singh discloses a plurality of particles that may be coated by weakly or strongly adsorbing surfactants or polymer additives to a core particle. The polymers thus adsorbed onto the abrasive particles can desorb from the particles during the polishing process to alter polishing characteristics and possibly result in damage to the polished surface.
There thus remains an unsatisfied demand for polymer-coated particles suitable for chemical mechanical polishing of magnetic, optical, semiconductor or silicon substrates.