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

We report the effect of off-bias stress on the transfer characteristics of short-channel (
L
= 0.95 μm) 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 cm
²
/V·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.