Polycrystalline Indium Gallium Tin Oxide Thin-Film Transistors With High Mobility Exceeding 100 cm<sup>2</sup>/Vs
Bo Kyoung Kim, Nuri On, Cheol Hee Choi, Min Jae Kim, Simeon Kang, Jun Hyung Lim, Jae Kyeong Jeong
Abstract
This letter reports the fabrication of high performance polycrystalline InGaSnO (IGTO) thin-film transistors (TFTs) at a low temperature of 400 °C. The microstructure of IGTO films was analyzed using X-ray diffraction and high-resolution transmission electron microscopy. The fabricated polycrystalline IGTO TFTs exhibited an unexpected high mobility of 116.5 cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> /Vs, threshold voltage of 0.47 V, low subthreshold gate swing of 134 mV/decade, and I <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">ON/OFF</sub> ratio of >1 × 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">9</sup> . Moreover, the stable behavior against external gate bias stress was observed for crystalline IGTO TFTs, which was attributed to the high degree of metal-oxygen lattice ordering.