Wafer-scale MoS2 for P-type field effect transistor arrays and defects-related electrical characteristics

Because of their fascinating electrical/optoelectrical characteristics, two-dimensional molybdenum disulphide (MoS2) attracts much attention recently. However, it is still a challenge to fabricate wafer-scale MoS2 nanofilms of controlled thickness and high quality and that, limits their application. Here, a two-step thermal vulcanization method is proposed to fabricate wafer-scale MoS2 nanofilms with different thicknesses (3-10 layers). The synthesized MoS2 nanofilms have high uniformity and good quality. Furthermore, back gate field effect transistor (FET) arrays were fabricated based on these wafer-scale MoS2 nanofilms. The FET devices showed good electrical performance, mobility in the range of 0.44 - 0.96 cm2V- 1s-1 and on/off ratio of -103. Here, first-principle calculation was used to analyse the different types of defects observed in the tri-layer MoS2, the doping effects induced by the defects were also discussed. This work provides a reliable way to fabricate wafer-scale MoS2 nanofilms and give a detailed study of the electrical properties of multilayers MoS2 nanofilms paving the way for the manufacture of two-dimensional semiconductor materials.