The modified bias-stress effect in organic TFTs

In this paper, the influence of drain bias on the bias stress effect in pentacene-based organic thin-film transistors was studied. It was found that, under gate bias stress measurement, the threshold voltage shift was strongly affected by the drain bias due to the varied channel charge amount. As a result, conventional stretched-exponential function was modified with a channel charge normalization factor to describe the dependence of threshold voltage shift on the stressing time. The result is important for the design of organic electronic or OTFT active-matrix display, in which the influence of both the gate and the drain biases has to be considered.