Modeling of kink effect in polycrystalline silicon thin-film transistors

A new analytical DC model accounting for the kink effect of polycrystalline silicon thin-film transistors (poly-Si TFTs) is presented in this paper. When considering the exponential density of trap states in the film, a quasi-two-dimensional approach is used to give an analytic expression for avalanche multiplication factor. Compared with the available experimental data, the proposed model provides accurate description of the output characteristics over a wide range of bias voltages. Based on the kink model, higher drain voltages or higher trap states density leads to higher avalanche multiplication factors.