Numerical Simulation for Operation of Flexible Thin-Film Transistors With Bending

We theoretically study the change of the performance characteristics with various mechanical bending conditions for flexible thin-film transistors (TFTs) by two-dimensional device simulation. The characteristics of newly developed flexible TFTs with high crystalline quality and high carrier mobility are more sensitive to the degree of bending. We developed a model to estimate the change in the characteristics as a function of curvature radius of the channel with a focus on scattering of carriers in a bent TFT. Field-effect mobility decreases by bending, e.g., ~11% with a radius at R = 30 mm and a knee voltage increases, while a threshold voltage remains the same. This model can be extended to other flexible TFTs with bending.