Based on the diffusion and thermal emission processes
an analytical subthreshold current model for polysilicon thin film transistors (poly-Si TFTs) is developed by a quasi- two-dimensional solution. An analytical expression of the subthreshold swing is subsequently obtained from the surface potential equation and the subthreshold current expression
which takes into account the grain size and trap states. This model has a simple functional form and it can reduce to that of the conventional long channel MOSFET in the case of large grain size and low trap states. The model has been verified by a good agreement between simulated results and experimental data.
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references
Wu W J, Yao R H. A simple model of DIGBL effect for polysilicon films and polysilicon thin-film transistors
. IEEE Electron Devices Letters, 2008, 29(10): 1128-1131.
Lin P S, Guo J Y, Wu C Y. A quasi-two-dimensional analytical model for the turn-on characteristics of polysilicon thin-film transistors
. IEEE Trans. Electron Devices, 1990, 37(3): 666-674.
Wong M, Chow T, Wong C C, et al. A quasi two-dimensional conduction model for polycrystalline silicon thin-film transistor based on discrete grains
. IEEE Trans. Electron Devices, 2008, 55(8):2148-2155.
Wu W J, Yao R H, Zheng X. A new analytical threshold voltage model for the doped polysilicon thin-film transistors
. Solid-State Electronics, 2009, 53:607-612.
Brews J R. Subthreshold behavior of uniformly and nonuniformly doped long-channel MOSFET
. IEEE Trans. Electron Devices, 1979, ED-26(9):1282-1291.
Iniguez B, Fjeldly T A. Unified substrate current model for MOSFETs
. Solid State Electron, 1997, 46(1):87-94.
Iniguez B, Xu Z, Fjeldly TA, et al. Unified model for short-channel poly-Si TFTs
. Solid State Electron, 1999, 43:1821-1831.
Jacunski M D, Shur M S, Oswusu A A, et al. A short-channel DC SPICE model for polysilicon thin-film transistors including temperature effects
. IEEE Trans. Electron Devices, 1999, 46(6):1146-1158.