Title :
Degradation Behaviors of Metal-Induced Laterally Crystallized n-Type Polycrystalline Silicon Thin-Film Transistors Under DC Bias Stresses
Author :
Xue, Min ; Wang, Mingxiang ; Zhu, Zhen ; Zhang, Dongli ; Wong, Man
Author_Institution :
Dept. of Microelectron., Soochow Univ., Suzhou
Abstract :
Device degradation behaviors of typical-sized n-type metal-induced laterally crystallized polycrystalline silicon thin-film transistors were investigated in detail under two kinds of dc bias stresses: hot-carrier (HC) stress and self-heating (SH) stress. Under HC stress, device degradation is the consequence of HC induced defect generation locally at the drain side. Under a unified model that postulates, the establishment of a potential barrier at the drain side due to carrier transport near trap states, device degradation behavior such as asymmetric on current recovery and threshold voltage degradation can be understood. Under SH stress, a general degradation in subthreshold characteristic was observed. Device degradation is the consequence of deep state generation along the entire channel. Device degradation behaviors were compared in low Vd-stress and in high Vd-stress condition. Defect generation distribution along the channel appears to be different in two cases. In both cases of SH degradation, asymmetric on current recovery was observed. This observation, when in low Vd-stress condition, is tentatively explained by dehydrogenation (hydrogenation) effect at the drain (source) side during stress
Keywords :
hot carriers; silicon; thermal stresses; thin film transistors; DC bias stresses; current recovery; defect generation distribution; degradation behaviors; device degradation; hot-carrier stress; metal-induced laterally crystallized n-type polycrystalline silicon thin-film transistors; self-heating stress; Crystallization; Degradation; Glass; Hot carriers; Silicon; Stress; Substrates; Temperature; Thin film transistors; Threshold voltage; Hot-carrier (HC) degradation; low-temperature polycrystalline silicon (LTPS); metal-induced lateral crystallization; reliability; self-heating (SH) degradation; thin-film transistors (TFTs);
Journal_Title :
Electron Devices, IEEE Transactions on
DOI :
10.1109/TED.2006.888723