Area-Selective UV Laser-Assisted Oxidation for Efficient Hole Injection in WSe 2 FETs and Its Application to Multifunctional Logic Operations

Among two-dimensional (2D) semiconductors, WSe 2 is a promising channel material for next-generation low-power, high-density electronics; however, high contact resistance at the metal/WSe 2 interface remains a critical bottleneck in achieving optimal p -type channel performances. Herein, a 325-nm ultraviolet laser-assisted localized oxidation process is proposed to form sub-stoichiometric WO X near the metal contact to modulate contact properties. Lateral force microscopy is utilized to verify the presence of WO X domains through a distinct friction contrast and statistical roughness evolution, showing excellent agreement with high-resolution transmission electron microscopy and energy-dispersive X-ray spectroscopy measurement. WO X induces localized p -type doping, reduces the effective Schottky barrier height, and lowers contact resistance by nearly four orders of magnitude without deg…