Dynamic HC-induced degradation in n-type poly-Si thin film transistors under off-state gate pulse voltage

摘要

Degradation behaviors of low temperature polycrystalline silicon (LTPS) thin-film transistors (TFTs) under gate pulse stresses immersing off-state are investigated. Hot carrier (HC) effect dominates the device degradation, which is determined by pulse base voltage (Vg_b) and falling time (tj). More negative Vg_b and steeper tf stimulate HC degradation severely and degenerate the device more seriously. Such kind of HC induced degradation can be explained by a non-equilibrium PN junction model during dynamic transition, in which the HCs is generated by the trapped carries emitting in high electric field of PN depleted region.