Numerical simulations of on and off state characteristics of polysilicon thin film transistors

Good agreement between numerical simulations and experimental data on the electrical characteristics of polycrystalline silicon (poly-Si) thin film transistors (TFTs) is shown. The field-effect mobility, threshold voltage, leakage current, and kink effect are examined. It is shown how the on-state performance of these devices can be modeled using an effective medium approach. Leakage currents are modeled by adding a single tunneling trap with a temperature-independent tunneling mechanism. The bias, temperature, and statistical behavior of leakage currents in poly-Si TFTs have been successfully simulated.