Drain-Induced Barrier Lowering in Short-Channel Poly-Si TFT After Off-Bias Stress Using Metal-Induced Crystallization of Amorphous Silicon

摘要

We report the effect of off-bias stress on the transfer characteristics of short-channel $(L = hbox{0.95} muhbox{m})$ low-temperature polycrystalline silicon (poly-Si) thin-film transistor (TFT). The poly-Si TFT using metal-mediated crystallization of a-Si exhibited a field-effect mobility of 93.07 $hbox{cm}^{2}/hbox{V}cdothbox{s}$ . In addition to the reduction of off-state leakage currents, threshold voltage shifts of 2.28 and 3.45 V were observed after off-bias stress at the drain voltages of $-$0.1 V and $-$ 1 V, respectively. This is attributed to the reduction of the effective channel length and to drain-induced barrier lowering effect, which lead to different current–voltage characteristics when the source/drain electrodes are exchanged.