Fermi-Level Pinning Mechanism in MoS2 Field-Effect Transistors Developed by Thermionic Emission Theory

Applied Sciences

Jun Wang¹  Xiong Chen²  Jiawen Qiu²  Shaozu Hu²  Hao Zhang²  Yonghua Wu²  Xiangfeng Guan²  Jiale Zheng²  Guidong Wang²  Xicheng Wei³  Yu Zhang³ 

[1] College of Science, Shanghai Institute of Technology, Shanghai 201418, China;Organic Optoelectronics Engineering Research Center of Fujian’s Universities, College of Electronics and Information Science, Fujian Jiangxia University, Fuzhou 350108, China;School of Materials Science and Engineering, Shanghai University, Shanghai 200444, China;

关键词: fermi-level pinning;    MoS₂;    field-effect transistors;    thermionic emission theory;   

DOI  :  10.3390/app10082754

来源: DOAJ

【 摘 要 】

Molybdenum disulfide (MoS₂) field-effect transistors (FETs) with four different source and drain metallic electrodes (Au, Ag, Al, Cu) were fabricated by mechanical exfoliation and vacuum evaporation methods. The mobility of the devices was (Au) 21.01, (Ag) 23.15, (Al) 5.35 and (Cu) 40.52 cm²/Vs, respectively. Unpredictably, the on-state currents of four devices were of the same order of magnitude with no obvious difference. For clarifying this phenomenon, we calculated the Schottky barrier height (SBH) of the four metal–semiconductor contacts by thermionic emission theory and found that Fermi-level pinning (FLP) existed in the metal–semiconductor contacts. We suppose the FLP may be caused by surface states of the semiconductor produced from crystal defects.

【 授权许可】

Unknown