High-Performance Monolayer WSe2 p/n FETs via Antimony-Platinum Modulated Contact Technology towards 2D CMOS Electronics

Abstract

Low resistance contact technology for 2D semiconductors is a key bottleneck for the practical application of 2D channel materials at advanced logic nodes. This work presents a novel Sb-Pt modulated contact technology which can alleviate the Fermi-level pinning effect and mediate the band alignment at the metal-2D semiconductor interface, leading to exceptional ohmic contacts for both p-type and n-type WSe2 FETs (p/n FET). WSe2 FETs with different Sb/Pt contact compositions, in combination with new oxide-based encapsulation/doping technologies, exhibits record low pFET contact resistance of 0.75 mathrm{k} Omega bullet mu mathrm{m} among all reported monolayer (1L) 2D pFETs. The nFET contact resistance of 1.8 mathrm{k} Omega bullet mu mathrm{m} is also the lowest among 1L WSe2 nFETs. Both 1L WSe2 pFET and nFET demonstrated remarkable on-state p/n current sim 150 mu mathrm{A}/ mu mathrm{m} at vert mathrm{V}-{D} vert =1 mathrm{V}, indicating the potential of WSe2 for CMOS applications. A new version of the semi-automated dry transfer process for chemical vapor deposition (CVD) WSe2 was also developed utilizing a novel Bi/PMMA/TRT support stack, offering low defect wrinkle-free WSe2 transfer at wafer-scale.