Analysis of Enhanced Degradation Under Dynamic Negative Bias Temperature Instability (NBTI) Condition in Low-Temperature Polycrystalline Silicon Thin-Film Transistors (LTPS TFTs)

In this research, an intensified degradation in low-temperature polycrystalline silicon thin-film transistors (LTPS TFTs) under dynamic negative bias temperature instability (NBTI) conditions is observed. The mechanism responsible for this intensified degradation is proposed and explained. Specifically, the rising time causes an increase in channel potential, leading to additional hole flow into the channel region from the source/drain, which intensifies the NBTI reaction. This phenomenon results in more severe degradation under dynamic conditions compared to steady conditions. Furthermore, degradation at varying frequencies remains more severe than under steady conditions, as any transient operation intensify degradation, unlike the steady-state condition in steady operation. The identified mechanism is crucial for NBTI degradation analysis and contributes to a deeper understanding of dynamic NBTI effects in LTPS TFTs, synthesizing both previous literature and the findings of this research.