2023 User Research Highlights
Heterogeneous integration of atomically thin semiconductors for non-von Neumann CMOS

Project summary: Transition metal dichalcogenides (TMDs) are seen as potential candidates for complementary metal oxide semiconductor (CMOS) technology in future nodes. While high performance field effect transistors (FETs), logic gates, and integrated circuits (ICs) made from n-type wafer-scale MoS2 and WS2 have been demonstrated, realizing CMOS electronics necessitates integration of large area p-type semiconductors. Furthermore, the physical separation of memory and logic is a bottleneck of the existing CMOS technology and must be overcome to reduce the energy burden for computation. In this article, the existing limitations are overcome and for the first time, a heterogeneous integration of large area grown n-type MoS2 and p-type vanadium doped WSe2 FETs with non-volatile and analog memory storage capabilities to achieve a non–von Neumann 2D CMOS platform is introduced. This manufacturing process flow allows for precise positioning of n-type and p-type FETs, which is critical for any IC development. Inverters and a simplified 2-input-1-output multiplexers and neuromorphic computing primitives using this non–von Neumann 2D CMOS platform are also demonstrated. This demonstration shows the feasibility of heterogeneous

integration of wafer scale 2D materials.

Publication: R. Pendurthi, et al. Small 2022, 18, 2202590.

2DCC Role: Wafer scale MoS2 monolayers grown by MOCVD in the 2DCC-MIP facility were used in the study.

What Has Been Achieved: Bottom-up fabrication process for heterogeneous integration of large area MoS2 and V-doped WSe2 for 2D CMOS technology and integration of non-volatile and analog memory storage with the 2D FETs for demonstration of post-von Neumann CMOS.

Importance of the Achievement: Demonstration of feasibility of heterogeneous integration of wafer-scale 2D materials.

Unique Feature(s) of the MIP that Enabled this Achievement: 2DCC-MIP’s MOCVD growth of high-quality, wafer-scale MoS2 films.

Publication: R. Pendurthi, D. Jayachandran, A. Kozhakhmetov, N. Trainor, J.A. Robinson, J.M. Redwing and S. Das, “Heterogeneous integration of atomically thin semiconductors for non-von Neumann CMOS,” Small 2022, 18, 2202590.

Acknowledgements: This work was supported by Army Research Office (ARO) through Contract Number W911NF1920338. The authors also acknowledge the materials support from the National Science Foundation (NSF) through the Pennsylvania State University 2D Crystal Consortium–Materials Innovation Platform (2DCCMIP) under NSF cooperative agreement DMR-1539916 and DMR-2039351. The work was also supported by the National Science Foundation (NSF) through a CAREER  grant ECCS-2042145.