The development of silicon semiconductor technology has produced breakthroughs in electronics—from the microprocessor in the late 1960s to early 1970s, to automation, computers and smartphones—by downscaling the physical size of devices and wires to the nanometre regime. Now, graphene and related two-dimensional (2D) materials offer prospects of unprecedented advances in device performance at the atomic limit, and a synergistic combination of 2D materials with silicon chips promises a heterogeneous platform to deliver massively enhanced potential based on silicon technology. Integration is achieved via three-dimensional monolithic construction of multifunctional high-rise 2D silicon chips, enabling enhanced performance by exploiting the vertical direction and the functional diversification of the silicon platform for applications in opto-electronics and sensing. Here we review the opportunities, progress and challenges of integrating atomically thin materials with silicon-based nanosystems, and also consider the prospects for computational and non-computational applications.
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Theis, T. N. & Wong, H. P. The end of Moore’s Law: a new beginning for information technology. Comput. Sci. Eng. 19, 41–50 (2017). A comprehensive overview of device miniaturization and computing systems, and the developing opportunities at the process, device and architecture levels to advance computing and information technology.
Dennard, R. H., Gaensslen, F. H., Rideout, V. L., Bassous, E. & LeBlanc, A. R. Design of ion-implanted MOSFET’s with very small physical dimensions. IEEE J. Solid-State Circuits 9, 256–268 (1974).
Taur, Y., Wann, C. H. & Frank, D. J. 25nm CMOS design considerations. In Proc. IEEE International Electron Devices Meeting (IEDM) 789–792 (IEEE, 1998).
Thompson, S. et al. A 90 nm logic technology featuring 50nm strained silicon channel transistors, 7 layers of Cu interconnects, low k ILD, and 1 μm2 SRAM cell. In Proc. 2002 IEEE International Electron Devices Meeting (IEDM) 61–64 (IEEE, 2002).
Mistry, K. et al. A 45nm logic technology with high-k+metal gate transistors, strained silicon, 9 Cu interconnect layers, 193nm dry pattering, and 100% Pb-free packaging. In Proc. 2007 IEEE International Electron Devices Meeting (IEDM) 247–250 (IEEE, 2007).
Frank, D. J., Taur, Y. & Wong, H.-S. Generalized scale length for two-dimensional effects in MOSFETs. IEEE Electron Device Lett. 19, 385–387 (1998).
Yan, R.-H., Ourmazd, A. & Lee, K. F. Scaling the Si MOSFET: from bulk to SOI to bulk. IEEE Trans. Electron Dev. 39, 1704–1710 (1992).
Suzuki, K., Tanaka, T., Tosaka, Y., Horie, H. & Arimoto, Y. Scaling theory for double-gate SOI MOSFET’s. IEEE Trans. Electron Dev. 40, 2326–2329 (1993).
Auth, C. et al. A 22nm high performance and low-power CMOS technology featuring fully-depleted tri-gate transistors, self-aligned contacts and high density MIM capacitors. In 2012 Symp. on VLSI Technology 131–132 (IEEE, 2012).
Loubet, N. et al. Stacked nanosheet gate-all-around transistor to enable scaling beyond FinFET. In 2017 Symp. on VLSI Technology T230–T231 (IEEE, 2017).
English, C. D., Shine, G., Dorgan, V. E., Saraswat, K. C. & Pop, E. Improved contacts to MoS2 transistors by ultra-high vacuum metal deposition. Nano Lett. 16, 3824–3830 (2016).
English, C. D., Smithe, K. K., Xu, R. L. & Pop, E. Approaching ballistic transport in monolayer MoS2 transistors with self-aligned 10 nm top gates. In Proc. 2016 IEEE International Electron Devices Meeting (IEDM) 131–134 (IEEE, 2016).
Desai, S. B. et al. MoS2 transistors with 1-nanometer gate lengths. Science 354, 99–102 (2016). An engineering accomplishment reporting a working MoS 2 transistor with the gate length defined by a 1-nm carbon nanotube.
Yang, L. et al. How important is the metal–semiconductor contact for Schottky barrier transistors: a case study on few-layer black phosphorus? ACS Omega 2, 4173–4179 (2017).
McGuire, F. A. et al. Sustained sub-60 mV/decade switching via the negative capacitance effect in MoS2 transistors. Nano Lett. 17, 4801–4806 (2017).
Si, M. et al. Steep-slope hysteresis-free negative capacitance MoS2 transistors. Nat. Nanotechnol. 13, 24–28 (2018).
Sabry Aly, M. M. et al. Energy-efficient abundant-data computing: the N3XT 1,000 x. Computer 48, 24–33 (2015).
Ferrari, A. C. et al. Science and technology roadmap for graphene, related two-dimensional crystals, and hybrid systems. Nanoscale 7, 4587–5062 (2015).
Goossens, S. et al. Broadband image sensor array based on graphene–CMOS integration. Nat. Photon. 11, 366–371 (2017). First report of an integrated graphene–Si camera microchip.
Mortazavi Zanjani, S. M., Holt, M., Sadeghi, M. M., Rahimi, S. & Akinwande, D. 3D integrated monolayer graphene–Si CMOS RF gas sensor platform. npj 2D Mater. Applicat. 1, 36 (2017).
Xia, F., Wang, H., Xiao, D., Dubey, M. & Ramasubramaniam, A. Two-dimensional material nanophotonics. Nat. Photon. 8, 899 (2014).
Sun, Z., Martinez, A. & Wang, F. Optical modulators with 2D layered materials. Nat. Photon. 10, 227–238(2016).
Joshi, N. et al. A review on chemiresistive room temperature gas sensors based on metal oxide nanostructures, graphene and 2D transition metal dichalcogenides. Mikrochim. Acta 185, 213 (2018).
Zhu, C., Du, D. & Lin, Y. Graphene-like 2D nanomaterial-based biointerfaces for biosensing applications. Biosens. Bioelectron. 89, 43–55 (2017).
Wang, Y.-H., Huang, K.-J. & Wu, X. Recent advances in transition-metal dichalcogenides based electrochemical biosensors: a review. Biosens. Bioelectron. 97, 305–316 (2017).
Huang, L. et al. Graphene/Si CMOS hybrid Hall integrated circuits. Sci. Rep. 4, 5548 (2014).
Cheng, C. et al. Monolithic optoelectronic integrated broadband optical receiver with graphene photodetectors. Nanophotonics 6, 1343–1352 (2017).
Goldsmith, B. R. et al. Digital biosensing by foundry-fabricated graphene sensors. Sci. Rep. 9, 434 (2019).
Image Sensors Market https://www.psmarketresearch.com/market-analysis/image-sensors-market (P&S Intelligence, 2017)
Koppens, F. H. L. et al. Photodetectors based on graphene, other two-dimensional materials and hybrid systems. Nat. Nanotechnol. 9, 780–793(2014).
NGMN 5G White Paper https://www.ngmn.org/5g-white-paper/5g-white-paper.html (Next Generation Mobile Networks Alliance, 2015).
van Uden, R. G. H. et al. Ultra-high-density spatial division multiplexing with a few-mode multicore fibre. Nat. Photon. 8, 865–870 (2014).
Arakawa, Y., Nakamura, T., Urino, Y. & Fujita, T. Silicon photonics for next generation system integration platform. IEEE Commun. Mag. 51, 72–77 (2013).
Romagnoli, M. et al. Graphene-based integrated photonics for next-generation datacom and telecom. Nat. Rev. Mater. 3, 392–414 (2018).
Fiori, G. et al. Electronics based on two-dimensional materials. Nat. Nanotechnol. 9, 768–779 (2014); erratum 9, 1063 (2014).
Chhowalla, M., Jena, D. & Zhang, H. Two-dimensional semiconductors for transistors. Nat. Rev. Mater. 1, 16052 (2016).
Akinwande, D., Petrone, N. & Hone, J. Two-dimensional flexible nanoelectronics. Nat. Commun. 5, 5678 (2014).
Sarkar, D. et al. A subthermionic tunnel field-effect transistor with an atomically thin channel. Nature 526, 91–95 (2015).
Iannaccone, G., Bonaccorso, F., Colombo, L. & Fiori, G. Quantum engineering of transistors based on 2D materials heterostructures. Nat. Nanotechnol. 13, 183–191 (2018); erratum 13, 520 (2018). Provides a perspective on the progress in 2D heterostructure transistor devices with benchmarking to Si technology, and the contemporary challenges that need to be addressed for future applications.
Resta, G. V. et al. Doping-free complementary logic gates enabled by two-dimensional polarity-controllable transistors. ACS Nano 12, 7039–7047 (2018).
Lee, K., Kulkarni, G. & Zhong, Z. Coulomb blockade in monolayer MoS2 single electron transistor. Nanoscale 8, 7755–7760 (2016).
Mishra, V. & Salahuddin, S. Intrinsic limits to contact resistivity in transition metal dichalcogenides. IEEE Electron Device Lett. 38, 1755–1758 (2017).
Liu, Y., Duan, X., Huang, Y. & Duan, X. Two-dimensional transistors beyond graphene and TMDCs. Chem. Soc. Rev. 47, 6388–6409 (2018).
Rai, A. et al. Air stable doping and intrinsic mobility enhancement in monolayer molybdenum disulfide by amorphous titanium suboxide encapsulation. Nano Lett. 15, 4329–4336 (2015).
Meric, I. et al. Graphene field-effect transistors based on boron–nitride dielectrics. Proc. IEEE 101, 1609–1619 (2013). Elucidates the properties of hBN and why it is ideal for graphene and, by extension, 2D transistors.
Teitz, L. & Toroker, M. C. Materials with honeycomb structures for gate dielectrics in two-dimensional field effect transistors – an ab initio study. Ceram. Int. 45, 9339–9347 (2018).
Yum, J. H. et al. Epitaxial ALD BeO: efficient oxygen diffusion barrier for EOT scaling and reliability improvement. IEEE Trans. Electron Dev. 58, 4384–4392 (2011).
Fuller, S. H. & Millett, L. I. Computing performance: game over or next level? Computer 44, 31–38 (2011).
Wong, H. S. & Salahuddin, S. Memory leads the way to better computing. Nat. Nanotechnol. 10, 191–194 (2015); erratum 10, 660 (2015).
Sohn, J., Lee, S., Jiang, Z., Chen, H. & Wong, H. P. Atomically thin graphene plane electrode for 3D RRAM. In Proc. 2014 IEEE International Electron Devices Meeting (IEDM) 116–119 (IEEE, 2014).
Lee, J. et al. Scalable high-performance phase-change memory employing CVD GeBiTe. IEEE Electron Device Lett. 32, 1113–1115 (2011).
Ahn, C. et al. Energy-efficient phase-change memory with graphene as a thermal barrier. Nano Lett. 15, 6809–6814 (2015).
Cao, W., Kang, J., Bertolazzi, S., Kis, A. & Banerjee, K. Can 2D-nanocrystals extend the lifetime of floating-gate transistor based nonvolatile memory? IEEE Trans. Electron Dev. 61, 3456–3464 (2014).
Ko, C. et al. Ferroelectrically gated atomically thin transition-metal dichalcogenides as nonvolatile memory. Adv. Mater. 28, 2923–2930 (2016).
Pan, C. et al. Coexistence of grain-boundaries-assisted bipolar and threshold resistive switching in multilayer hexagonal boron nitride. Adv. Funct. Mater. 27, 1604811 (2017).
Wu, X. et al. Thinnest nonvolatile memory based on monolayer h-BN. Adv. Mater. 31, 1806790 (2019).
Ge, R. et al. Atomristor: nonvolatile resistance switching in atomic sheets of transition metal dichalcogenides. Nano Lett. 18, 434–441 (2018). First report on memory effect in TMD monolayer vertical devices, alluding to a ubiquitous effect in non-metallic TMDs.
Zhang, F. et al. Electric-field induced structural transition in vertical MoTe2- and Mo1–xWxTe2-based resistive memories. Nat. Mater. 18, 55–61 (2019).
Sangwan, V. K. et al. Gate-tunable memristive phenomena mediated by grain boundaries in single-layer MoS2. Nat. Nanotechnol. 10, 403–406 (2015)
Kshirsagar, C. U. et al. Dynamic memory cells using MoS2 field-effect transistors demonstrating femtoampere leakage currents. ACS Nano 10, 8457–8464 (2016).
Steinhögl, W., Schindler, G., Steinlesberger, G. & Engelhardt, M. Size-dependent resistivity of metallic wires in the mesoscopic range. Phys. Rev. B 66, 075414 (2002).
Li, L. et al. Vertical and lateral copper transport through graphene layers. ACS Nano 9, 8361–8367 (2015).
Lee, C.-S., Cline, B., Sinha, S., Yeric, G. & Wong, H.-S. P. 32-bit processor core at 5-nm technology: analysis of transistor and interconnect impact on VLSI system performance. In Proc. 2016 IEEE International Electron Devices Meeting (IEDM) 691–694 (IEEE, 2016).
Lo, C.-L. et al. Studies of two-dimensional h-BN and MoS2 for potential diffusion barrier application in copper interconnect technology. npj 2D Mater. Applicat. 1, 42 (2017).
Li, L. et al. BEOL compatible graphene/Cu with improved electromigration lifetime for future interconnects. In Proc. 2017 IEEE International Electron Devices Meeting (IEDM) 240–243 (IEEE, 2017).
Jiang, J. et al. Intercalation doped multilayer-graphene-nanoribbons for next-generation interconnects. Nano Lett. 17, 1482–1488 (2017).
Liu, M., Yin, X. & Zhang, X. Double-layer graphene optical modulator. Nano Lett. 12, 1482–1485 (2012).
Sorianello, V., Midrio, M. & Romagnoli, M. Design optimization of single and double layer graphene phase modulators in SOI. Opt. Express 23, 6478–6490 (2015).
Sorianello, V. et al. Graphene–silicon phase modulators with gigahertz bandwidth. Nat. Photon. 12, 40–44 (2018).
Schuler, S. et al. Controlled generation of a p–n junction in a waveguide integrated graphene photodetector. Nano Lett. 16, 7107–7112 (2016).
Schall, D. et al. Record high bandwidth integrated graphene photodetectors for communication beyond 180 Gb/s. In Optical Fiber Communication Conf. M2I.4 (Optical Society of America, 2018).
Lemme, M. C. et al. Gate-activated photoresponse in a graphene p–n junction. Nano Lett. 11, 4134–4137 (2011).
Shiue, R.-J. et al. High-responsivity graphene–boron nitride photodetector and autocorrelator in a silicon photonic integrated circuit. Nano Lett. 15, 7288–7293 (2015).
Hu, Y. T. et al. Broadband 10Gb/s graphene electro-absorption modulator on silicon for chip-level optical interconnects. In Proc. 2014 IEEE International Electron Devices Meeting (IEDM) 128–131 (IEEE, 2014).
Yang, C. et al. Enabling monolithic 3D image sensor using large-area monolayer transition metal dichalcogenide and logic/memory hybrid 3D+IC. In Proc. 2016 IEEE Symp. on VLSI Technology 1–2 (IEEE, 2016).
Haastrup, S. et al. The computational 2D materials database: high-throughput modeling and discovery of atomically thin crystals. 2D Mater. 5, 042002 (2018).
Molle, A. et al. Buckled two-dimensional Xene sheets. Nat. Mater. 16, 163–169 (2017).
Mounet, N. et al. Two-dimensional materials from high-throughput computational exfoliation of experimentally known compounds. Nat. Nanotechnol. 13, 246–252 (2018). A comprehensive computational study to identify a wider portfolio of diverse 2DMs beyond what is experimentally known.
Gao, L., Guest, J. R. & Guisinger, N. P. Epitaxial graphene on Cu(111). Nano Lett. 10, 3512–3516 (2010).
Huang, M. et al. Highly oriented monolayer graphene grown on a Cu/Ni(111) alloy foil. ACS Nano 12, 6117–6127 (2018).
Ago, H. et al. Epitaxial chemical vapor deposition growth of single-layer graphene over cobalt film crystallized on sapphire. ACS Nano 4, 7407–7414 (2010).
Verguts, K. et al. Controlling water intercalation is key to a direct graphene transfer. ACS Appl. Mater. Interfaces 9, 37484–37492 (2017).
Rahimi, S. et al. Toward 300 mm wafer-scalable high-performance polycrystalline chemical vapor deposited graphene transistors. ACS Nano 8, 10471–10479 (2014). An engineering achievement, demonstrating the growth of large-area monolayer graphene on industrial-scale 300-mm Si wafers.
Lee, J.-H. et al. Wafer-scale growth of single-crystal monolayer graphene on reusable hydrogen-terminated germanium. Science 344, 286–289 (2014).
Choi, W. et al. Recent development of two-dimensional transition metal dichalcogenides and their applications. Mater. Today 20, 116–130 (2017).
Kang, K. et al. High-mobility three-atom-thick semiconducting films with wafer-scale homogeneity. Nature 520, 656–660 (2015).
Zhou, J. et al. A library of atomically thin metal chalcogenides. Nature 556, 355–359 (2018). A scientific achievement, demonstrating that salt-assisted chemical vapour deposition is a facile method for growing dozens of diverse 2D transitional metal chalcogenides.
Li, H. et al. Laterally stitched heterostructures of transition metal dichalcogenide: chemical vapor deposition growth on lithographically patterned area. ACS Nano 10, 10516–10523 (2016).
Xie, S. et al. Coherent, atomically thin transition-metal dichalcogenide superlattices with engineered strain. Science 359, 1131–1136 (2018).
Guimarães, M. H. D. et al. Atomically thin ohmic edge contacts between two-dimensional materials. ACS Nano 10, 6392–6399 (2016).
Antonio, R. et al. Scalable synthesis of WS2 on graphene and h-BN: an all-2D platform for light-matter transduction. 2D Mater. 3, 031013 (2016).
Li, X. et al. Large-area synthesis of high-quality and uniform graphene films on copper foils. Science 324, 1312–1314 (2009).
Huang, J.-K. et al. Large-area synthesis of highly crystalline WSe2 monolayers and device applications. ACS Nano 8, 923–930 (2014).
Boyd, D. A. et al. Single-step deposition of high-mobility graphene at reduced temperatures. Nat. Commun. 6, 6620 (2015)
Kim, J., Sakakita, H. & Itagaki, H. Low-temperature graphene growth by forced convection of plasma-excited radicals. Nano Lett. 19, 739–746 (2019).
Lee, E. et al. Heterogeneous solid carbon source-assisted growth of high-quality graphene via CVD at low temperatures. Adv. Funct. Mater. 26, 562–568 (2016).
Jang, J. et al. Low-temperature-grown continuous graphene films from benzene by chemical vapor deposition at ambient pressure. Sci. Rep. 5, 17955 (2015).
Fujita, J.-i. et al. Near room temperature chemical vapor deposition of graphene with diluted methane and molten gallium catalyst. Sci. Rep. 7, 12371 (2017).
Jurca, T. et al. Low-temperature atomic layer deposition of MoS2 films. Angew. Chem. Int. Ed. 56, 4991–4995 (2017).
Delabie, A. et al. Low temperature deposition of 2D WS2 layers from WF6 and H2S precursors: impact of reducing agents. Chem. Commun. 51, 15692–15695 (2015).
Chen, M., Haddon, R. C., Yan, R. & Bekyarova, E. Advances in transferring chemical vapour deposition graphene: a review. Mater. Horiz. 4, 1054–1063 (2017).
Liang, X. et al. Toward clean and crackless transfer of graphene. ACS Nano 5, 9144–9153 (2011).
Wang, B. et al. Support-free transfer of ultrasmooth graphene films facilitated by self-assembled monolayers for electronic devices and patterns. ACS Nano 10, 1404–1410 (2016).
Kang, K. et al. Layer-by-layer assembly of two-dimensional materials into wafer-scale heterostructures. Nature 550, 229–233 (2017)
Verguts, K., Coroa, J., Huyghebaert, C., De Gendt, S. & Brems, S. Graphene delamination using ‘electrochemical methods’: an ion intercalation effect. Nanoscale 10, 5515–5521 (2018).
Li, X.-L. et al. Layer-number dependent optical properties of 2D materials and their application for thickness determination. Adv. Funct. Mater. 27, 1604468 (2017).
Li, H. et al. Rapid and reliable thickness identification of two-dimensional nanosheets using optical microscopy. ACS Nano 7, 10344–10353 (2013).
Braeuninger-Weimer, P. et al. Fast, noncontact, wafer-scale, atomic layer resolved imaging of two-dimensional materials by ellipsometric contrast micrography. ACS Nano 12, 8555–8563 (2018).
Mak, K. F., Lee, C., Hone, J., Shan, J. & Heinz, T. F. Atomically thin MoS2: a new direct-gap semiconductor. Phys. Rev. Lett. 105, 136805 (2010).
Lee, J. E., Ahn, G., Shim, J., Lee, Y. S. & Ryu, S. Optical separation of mechanical strain from charge doping in graphene. Nat. Commun. 3, 1024 (2012)
Amani, M. et al. Near-unity photoluminescence quantum yield in MoS2. Science 350, 1065–1068 (2015).
Mignuzzi, S. et al. Effect of disorder on Raman scattering of single-layer MoS2. Phys. Rev. B 91, 195411 (2015).
Mennel, L. et al. Optical imaging of strain in two-dimensional crystals. Nat. Commun. 9, 516 (2018).
Buron, J. D. et al. Terahertz wafer-scale mobility mapping of graphene on insulating substrates without a gate. Opt. Express 23, 30721–30729 (2015).
Kiriya, D., Tosun, M., Zhao, P., Kang, J. S. & Javey, A. Air-stable surface charge transfer doping of MoS2 by benzyl viologen. J. Am. Chem. Soc. 136, 7853–7856 (2014).
Li, M.-Y., Su, S.-K., Wong, H.-S. P. & Li, L.-J. How 2D semiconductors could extend Moore’s law. Nature 567, 169–170 (2019).
The IC memory market will grow 40% to US$177 billion in 2018. AnySilicon https://anysilicon.com/ic-memory-market-will-grow-40-us177-billion-2018/ (Yole Développement, Yole Group of Companies, 2018).
Auth, C. et al. A 10nm high performance and low-power CMOS technology featuring 3rd generation FinFET transistors, self-aligned quad patterning, contact over active gate and cobalt local interconnects. In Proc. 2017 IEEE International Electron Devices Meeting (IEDM) 673–676 (IEEE, 2017).
Photonics is about to get flatter. Photonics Media https://www.photonics.com/Articles/Photonics_is_About_to_get_Flatter/a55428
Zuzak, K. et al. Novel hyperspectral imager aids surgeons. SPIE News http://www.spie.org/news/1394-novel-hyperspectral-imager-aids-surgeons?SSO=1 (SPIE, 2019).
D.A. acknowledges support from the US National Science Foundation (NSF), the US Office of Naval Research (ONR), and the Presidential Early Career Award for Scientists and Engineers (PECASE) through the US Army Research Office. C.-H.W. and H.-S.P.W. acknowledge support from the NSF, AFOSR MURI, the Semiconductor Research Corporation (SRC) STARnet FAME and SRC JUMP ASCENT, and member companies of the Stanford SystemX Alliance and the Stanford Non-Volatile Memory Technology Research Initiative (NMTRI). L.-J.L. and H.-S.P.W. acknowledge substantial management support from TSMC. C.H. acknowledges support from the Logic Imec Industrial Affiliation Program and funding from the Graphene Flagship initiative. F.H.L.K. acknowledges financial support from the Government of Catalonia through an SGR grant (2017, 1656), from the Spanish Ministry of Economy and Competitiveness through the “Severo Ochoa” Programme for Centres of Excellence in R&D (SEV-2015-0522), from Fundacio Cellex Barcelona, and from the CERCA Programme/Generalitat de Catalunya. Furthermore, the research leading to these results has received funding from the European Union Seventh Framework Programme under grant agreement no. 785219, Graphene Flagship.
The authors declare no competing interests.
Peer review information Nature thanks Jeehwan Kim and Frank Schwierz for their contribution to the peer review of this work.
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Akinwande, D., Huyghebaert, C., Wang, C. et al. Graphene and two-dimensional materials for silicon technology. Nature 573, 507–518 (2019). https://doi.org/10.1038/s41586-019-1573-9
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