P‐29: Influence of the Static Bending Stress on LTPS TFT

Abstract

We investigated the degradation behavior of p‐channel LTPS TFTs on PI substrate under the static bending stress. In order to evaluate the bending durability of flexible LTPS TFTs, device‐bending tests under different bending strains and directions have been performed. The performance of TFT under tensile bending stress degraded (ΔVth≈ 0.38V) worse than compressive bending stress (ΔVth ≈0.07V), which might be originated from both the generation of interface trap states (ΔNit) and channel boundary trap density (ΔNtrap) under tensile bending stress much higher than compression‐bent. In the meanwhile, the stress distribution has also been simulated. According to the results of test and simulation, we speculated the mechanical stress near the source and drain electrodes caused the traps in gate insulator, which in turn cause electron trapping.