A comprehensive analytic model of accumulation-mode MOSFET´s in PolySilicon thin films

A comprehensive analytic description of the polysilicon (poly-Si) MOSFET, operating in the accumulation mode is presented. The model is not a single crystalline analog. Rather, the formulation is based upon structural and electronic properties inherent in poly-Si thin films. The model is capable of quantitatively explaining the bulk of reported device characteristics, specifically the temperature coefficient of current (TCC). Drive and leakage current as a function of doping level are also quantitatively discussed. In addition, transconductance, drain admittance, and ON/OFF current ratio are described extensively at room temperature and above and are compared with experimental data. The role of grain boundary hydrogenation in effecting the device performance is quantified. Finally, a few pertinent design guidelines are presented.