Surface-Channel Drain-Avalanche Hot-Carrier Effect under Temperature Variation on CLC TFTs

Abstract

Continuous-wave green laser-crystallized (CLC) single-grainlike polycrystalline silicon n-channel thin-film transistors (poly-Si n-TFTs) exhibit the higher electron mobility and turn-on current than excimer laser annealing (ELA) poly-Si n-TFTs. Furthermore, high drain voltage accelerates the flowing electrons in n-type channel, and hence the energized electrons possibly cause a serious damage near the drain region and deteriorate the source/drain (S/D) current. Using this good reliability metrology to verify the quality of CLC n-TFTs was adopted. The degradation mechanisms of S/D current for CLC poly-Si n-TFTs were firstly investigated by measuring the gate-to-drain overlap capacitor, and with the drain-avalanche hot-carrier stresses at 2VGS = VDS =14 V and 2VGS =VDS =18 V in temperature environment, 25 oC and 50 oC.