Effect of Fabricating Process on the Performance of Two-Dimensional p-Type WSe2 Field Effect Transistors

Two-dimensional (2D) transition metal dichalcogenides (TMDs), such as WSe2, are promising candidates for next-generation integrated circuits. However, the dependence of intrinsic properties of TMD devices on various processing steps remains largely unexplored. Here, using pristine p-type WSe2 devices as references, we comprehensively studied the influence of each step in traditional nanofabrication methods on device performance. Our findings reveal that electron beam exposure significantly alters the electrical conductivity of WSe2 due to the doping and diffusion effects of electrons. During ultraviolet lithography, the bilayer WSe2 device immersed in a 4‰ NaOH developer also showed substantial quality degradation (40%–84%). In this case, we combined laser patterning with the transfer electrode method to fabricate a high-performance device with a current density of 278.5 μA/μm and an on/off ratio of 3.9 × 107. This work reveals the influence of the nanofabrication process on TMD devices and guides for improving device performance.