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.