  New design of silicon stripixel sensor has been developed at BNL for PHENIX
upgrade. The sensor is a single-sided, DC-coupled, two dimensional position
sensitive device with good position resolution. This design is simpler for
sensor fabrication and signal processing than the conventional double-sided
strip sensor. HPK has produced pre-production stripixel sensors with thickness
of 625 um. The quality assurance tests show that the very low leakage current
0.12 nA per strip allows the use of the SVX4 chip. A long term stability test
shows that the leakage current is stable over a long period of time. The study
of the effects of irradiation on the performance of the stripixel sensor has
been made using p+p collisions at 200 GeV at PHENIX, 14 MeV neutron and 20 MeV
proton beams.
