Comprehensive study on dynamic bias temperature instability of p-channel polycrystalline silicon thin-film transistors

Static negative and positive Bias Temperature Instability (BTI) in p-channel polycrystalline silicon thin-film transistors has been studied. However, dynamic stress condition is similar to the real operation. After dynamic BTI stress, the current increases initially and drops significantly (~0.1x) after long time stress. The change of I_ON is more serious for higher frequency, higher amplitude or shorter channel length devices. Only the falling edges during voltage transition count for the degradation during dynamic stress. With LDD structure, the lateral electric field is reduced, thus I_ON has much less degradation.