A dynamic current hysteresis model for IGZO-TFT

Abstract

This paper proposes a dynamic current hysteresis model for the Indium Gallium Zinc Oxide Thin Film Transistor (IGZO-TFT). Based on the Shockley-Read-Hall (SRH) theory, a kinetic equation that accurately describes the interface trap’s capture/emission behaviour is presented, which can incorporate the effect of interface trap density, trap energy level and scan rate dependency. Further, the kinetic equation is solved using a sub-circuit approach, combined with a calibrated TFT static current model, to achieve an accurate simulation of the current hysteresis of IGZO-TFT. This model has been validated with numerical TCAD simulations and has been shown to precisely reflect the effect of trap energy level, trap density and scan rate on the current hysteresis characteristics.