Integrable selective-area inverse n-doping of WSe₂ by ultrathin CaF₂ dielectrics for CMOS

Abstract Two-dimensional (2D) materials possess excellent electrical properties and are regarded as promising building blocks for future CMOS technology. However, their intrinsic unipolar conducting behavior, characterized by either n-type or p-type conductivity, necessitates the integration of two different materials as channels. This results in increased complexity during the fabrication of CMOS devices and performance mismatches. In this study, we propose an electrostatic doping strategy utilizing ultrathin CaF 2 as the gate dielectric layer, enabling the selective n-type doping of pristine p-type WSe 2 and facilitating the creation of a CMOS inverter. Raman and photoluminescence spectra, along with electrical characterization, consistently confirmed the n-type behavior of WSe 2 , aligning with our theoretical calculations. This research introduces a novel strategy for 2D-based CMOS devices and future integration, which is expected to generate significant scientific interest and application potential.