The Korean Society of Surface Science and Engineering

The availability of highly reliable p-type two-dimensional (2D) semiconductors is essential for implementing complementary logic circuits, low-power electronics, and multi-functional devices. Despite significant progress in 2D field-effect transistor (FET) research, studies on p-type materials and their device applications remain insufficient. In this study, we report on the fabrication and electrical characterization of p-type FET based on 2D tungsten diselenide (2D-WSe₂) synthesized via a two-step synthetic method. The optimized process involving sequential tungsten trioxide (WO₃) precursor deposition and selenization, yielded few-layer 2D-WSe₂ films with controlled thickness. The fabricated back-gate transistors exhibited a clear p-type conduction behavior, with an on/off current ratio exceeding 10³, a hole mobility of 0.03 cm²/V·s, and a low gate leakage current of < 0.2 nA. Also, the synaptic characteristics were evaluated under successive pulse measurements, and stable operation was confirmed up to 400 cycles.

키워드 2D-WSe₂; Two-step CVD selenization; Back-gate transistor; Synatpic properties; Field-effect mobility.