2D-Material-Channel Field-Effect Transistor for VLSI

Speaker: Ming Zhang
Affiliation: Ph.D. Candidate UCLA

Abstract: 2D materials have attracted tremendous attention for a variety of properties such as ultra-low body thickness, ultra-high mobility, tunable bandgap, etc. These unique merits of the 2D materials bring in the significant improvements and new perspective in the digital CMOS scaling, analog performance, as well as the 3D integration of the wafer stacking. In this dissertation, two kinds of 2D materials, namely the graphene and molybdenum disulfide (MoS₂), have been closely examined through material synthesis, device simulation and performance optimization.  The CVD growth of graphene sheet using copper as catalyst has been studied and compared in detail. The simulation of the graphene FET has been carried out based on the drift-diffusion model, which indicates the large impact of contact resistance on the on-state current. The contact resistivity for different metals on the graphene has been extracted by transmission line model (TLM) from experimental data.

The MoS₂ layer is synthesized by the sulfidation of pre-deposited MoO₃ and a post-sulfidation process has been adopted to improve the film quality. The contact metals and resistances are compared under the TLM structure. The non-linearity between the resistance and channel length is explained by the simulation of low-doped SOI film. The performance of MoS₂ FET is simulated and experimental measured. The scaling of the MoS₂ transistor is simulated and compared with the current technology FinFET and sSOI devices.

Biography: Ming Zhang received his B.S. degree in Academic Talented Program (ATP) in School of Science at Tsinghua University, and obtained his M.S. degree in Institute of Microelectronics at Tsinghua University. He is currently a Ph.D. candidate under Prof. Jason Woo in Department of Electrical Engineering at University of California, Los Angeles. His research interest includes the material synthesis, device simulation and process integration of 2D materials and nano-materials.

For more information, contact Prof. Jason C.S. Woo (woo@ee.ucla.edu)

Date/Time:
Date(s) - Mar 01, 2016
2:00 pm - 4:00 pm

Location:
E-IV Maxwell Room #57-124
420 Westwood Plaza - 5th Flr. , Los Angeles CA 90095