Modeling and Simulation of Hydrogenated Amorphous Silicon Thin-Film Transistors

Zoubeida Hafdi, Mohamed Salah Aida
2005 Japanese Journal of Applied Physics  
This paper focuses on the effects of surface states on the performance of hydrogenated amorphous silicon based thin-film transistors. An analytical model which simultaneously accounts for surface states at the gate insulator/amorphous silicon interface besides the localized states in the gap of amorphous silicon is derived for a coplanar structure. Through illustrative simulations, the current-voltage characteristics are derived. The field effect mobility-to-the band mobility ratio, the
more » ... f drain current ratio, the threshold voltage and the subthreshold swing are investigated to give a clear indication of these effects. An analytical approach to determine the characteristic temperature of the deep states in the presence of surface states at the insulator/a-Si interface is also proposed. It is demonstrated that surface states considerably affect transistor characteristics and accurate treatment of the device performance cannot neglect the presence of these states.
doi:10.1143/jjap.44.1192 fatcat:jbwdsvcb5bgyhfdte4cuhjtzfq