Blue Laser Annealed Sub-Micron Channel P-Type Low Temperature Poly-Si TFT Without Kink Effect for High-Resolution Display
Abu Bakar Siddik, Mohammad Masum Billah, Suhui Lee, Young Joo Cho, Seongbok Kang, Seonhyang Jang, Jihwang Park, Taeheon Lee, Jin Jang
Abstract
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 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">14</sup> cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-3</sup> s <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-1</sup> (~8 times) compared to 4.64 x 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">13</sup> cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-3</sup> s <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-1</sup> for protrusion-free LTPS TFTs. It is demonstrated that protrusion-free LTPS can achieve kink-free, sub-micron short channel devices.