Controllable p-Type Doping Strategy for High-Performance 2D Material Complementary Inverters

Controllable doping is required to modulate the electrical properties of the semiconductor devices. Such controllability is a particular issue in p-type doping for two-dimensional (2D) semiconductors. Here, we present a controllable doping strategy for modulating carrier density and threshold voltage of WSe₂ transistors via surface oxidation at 200 °C in air. The hole density in the WSe₂ channel can be precisely modulated from 1 × 10¹¹ cm^-2 to 3.5 × 10¹² cm^-2 by increasing oxidation duration, while its carrier mobility is virtually unaffected, maintaining a high value of 94.3 cm²·V^-1·s^-1. This controllable doping method can help to achieve balanced carrier transport in the n-type and p-type transistors in CMOS devices. The doped p-type WSe₂ transistor in a CMOS inverter resulted in a high gain of 52 and a lower static power of 0.256 nW at a bias voltage of 1 V. Therefore, our findings might pave the way for reliable fabrication of high-performance 2D electronic circuits.