We report fabrication processes of indium gallium zinc oxide (IGZO) and low temperature poly silicon (LTPS) hybrid TFTs array technology. And the SiOx/IGZO interface quality modification and the performance of different thickness of active layer of IGZO device has been investigated by positive gate bias temperature stress method. The optimum processes conditions have been used on the 1.4" inch circular LCD to improve and pass operation tests of high temperature operation (HTO) 274hrs and temperature-humidity-bias (THB) 462 hrs to reach mass production phase.

Because of the unique property, the low leakage current of crystalline indium gallium zinc oxide (c-IGZO) thin film transistors (TFTs), it can archive the low power consumption of a panel within low frame rate driving. Low temperature poly-silicon (LTPS) TFTs as components of shift register circuit can fulfill small border size. The c-IGZO TFTs for pixel switch and the LTPS TFTs for gate driver on array backplane have been both deposited on glass substrate. We demonstrate a prototype of 1.4 inch circular LCD with c-IGZO and LTPS hybrid backplane technology to achieve small border size and low power consumption. And the panel shows good picture quality without flickering when very low frame rate driving (6Hz). In addition, the optical property and crystallinity of c-IGZO have been studied in this work.

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Crystalline indium gallium zinc oxide (c-IGZO) on glass substrate was deposited and characterized. The crystallinity of IGZO in the active layers is all highly crystallized by nano-beam electron diffraction (NBED) analysis. High-resolution transmission electron microscopy (HRTEM) image shows the formation of c-IGZO with c-axis alignment. The main peak of the c-IGZO is in (009) planes by X-ray diffraction (XRD). The d-spacing in NBED pattern by comparing with the d-spacing of Silicon wafer in NBED pattern is 2.9 Å, which almost equals to the value of powder diffraction file (PDF) data base of InGaZnO4.[1]

Abstract— A photodetector using a silicon‐nanocrystal layer sandwiched between two electrodes is proposed and demonstrated on a glass substrate fabricated by low‐temperature poly‐silicon (LTPS) technology. Through post excimer‐laser annealing (ELA) of silicon‐rich oxide films, silicon nanocrystals formed between the bottom metal and top indium thin oxide (ITO) layers exhibit good uniformity, reliable optical response, and tunable absorption spectrum. Due to the quantum confinement effect leading to enhanced phonon‐assisted excitation, these silicon nanocrystals, less than 10 nm in diameter, promote electron‐hole‐pair generation in the photo‐sensing region as a result resembling a direct‐gap transition. The desired optical absorption spectrum can be obtained by determining the thickness and silicon concentration of the deposited silicon‐rich oxide films as well as the power of post laser annealing. In addition to obtaining a photosensitivity comparable to that of the p‐i‐n photodiode currently used in LTPS technology, the silicon‐nanocrystal‐based photosensor provides an effective backlight shielding by the bottom electrode made of molybdenum (Mo). Having a higher temperature tolerance for both the dark current and optical responsibility and maximizing the photosensing area in a pixel circuit by adopting a stack structure, this novel photosensor can be a promising candidate for realizing an optical touch function on a LTPS panel.