Blue Laser Annealed Sub-Micron Channel P-Type Low Temperature Poly-Si TFT Without Kink Effect for High-Resolution Display

We report sub-micron channel length (0.5 μm), low-temperature polysilicon(LTPS) thin-film transistor (TFT) using blue laser annealing (BLA) for ultra-high-resolution displays. The TFTs exhibited negligible kink effect in output characteristics with excellent negative bias temperature stability. Protrusion-free BLA LTPS is evident from the transmission electron microscopy (TEM) image. Technology computer-aided design (TCAD) simulation reveals that the protruded LTPS with grain boundaries has ~1.4 times higher electric field than protrusion-free LTPS. This causes high impact generation rate of 3.76 x 10¹⁴ cm^-3 s^-1 (~8 times) compared to 4.64 x 10¹³ cm^-3s^-1 for protrusion-free LTPS TFTs. It is demonstrated that protrusion-free LTPS can achieve kink-free, sub-micron short channel devices.