Geometrical Impact of High Curvature Bending on the Performance of Thin Film Transistors

The impact of high curvature bending on thin film transistor(TFT) performance is of interest for flexible electronics. Bending influences TFT performance in two ways. First due to mechanical stress and second due to the pure geometric effect of converting a planar architecture to a cylindrical one. Experiments to simultaneously create and yet distinguish these two effects are difficult. Analytical models are required to identify the individual impact of stress and geometry. The goal of this work is to identify the purely geometrical impact on TFT characteristics. Closed form solutions of the Poisson-Boltzmann equation in polar coordinates are obtained and compared with TCAD simulations. The models are validated using experimental data for a buckled gate TFT.

高曲率弯曲对薄膜晶体管（TFT）性能的影响，对于柔性电子领域具有重要意义。弯曲对TFT性能的影响主要体现在两个方面：首先，由于机械应力的作用；其次，由于将平面结构转换为圆柱形结构的纯粹几何效应。同时创造并区分这两种效应的实验颇具挑战性。为了识别应力和几何形状的单独影响，需要建立分析模型。本工作的目标在于识别对TFT特性产生的纯粹几何影响。通过极坐标中泊松-玻尔兹曼方程的封闭形式解，并与TCAD模拟进行比较。利用扭曲栅极TFT的实验数据对这些模型进行验证。