Large-Area Monolayer p-Type Semiconductor Films Toward High-Performance Electrical Device Arrays

2D semiconductors open new avenues in the post-Moore era for semiconductor technologies immune from the short-channel effect due to their atomic-scale thicknesses and dangling-bond-free surfaces. However, it still remains a big challenge to obtain large-area and high-quality monolayer p-type semiconductors so far. Herein, a controlled nucleation is realized by tuning the evaporation areas of Se precursors during the p-type WSe₂ growth. By optimizing the nucleation density, centimeter-scale uniform monolayer WSe₂ and Nb-incorporated WSe₂ films are synthesized. The field effect transistor array based on WSe₂ film exhibits p-type behavior with hole mobilities of 34 ± 17 cm² V^-1 s^-1 and an average on/off ratio of 4 × 10⁷, which can be further improved by Nb incorporation with much higher hole mobility of 48 ± 16 cm² V^-1 s^-1 with an average on/off ratio of ≈10⁸. The work paves the way for synthesizing large-scale uniform 2D p-type semiconductors for electrical devices and integrated circuits.