近年來，基於高靈敏度，結構簡單，製造成本低的優點，許多種金屬氧化物半導體(MOS)感測器已被廣泛探討。氧化銦鎵鋅(IGZO)是一種新型n型半導體材料，由於固有的高電子遷移率( > 10 cm2/v·s)、柔韌性、低溫兼容製程的特徵，已經廣泛使用於LCD薄膜電晶體(TFT)技術中。然而，在電阻式氣體感測器的應用上，此材料的相關文獻相對較少。因此，在本論文中，分別利用三種不同的金屬(Pd、Pt、Au)修飾IGZO薄膜表面，最後，由實驗得知，於檢測氫氣、氨氣和甲醛都有良好的性能。本研究也運用掃描電子顯微鏡(SEM)，X射線繞射儀(XRD)，能量色散X射線光譜儀(EDS)、 穿透式電子顯微鏡(TEM)和原子力分析顯微鏡(AFM)來分析氧化銦鎵鋅(IGZO)電阻式氣體感測器的元件結構，表面形貌、金屬奈米粒子的大小和元素組成。

In recent years, many kinds of metal oxide semiconductor sensors have been extensively investigated due to the high sensitivity, simple structures, and low-cost fabrication. Indium gallium zinc oxide (IGZO) is a new n-type semiconductor material. Because of its inherent characteristics of high electron mobility (> 10 cm2/v·s), flexibility, and low-temperature compatible fabrication processes, it has been widely used in LCD displays as a transparent thin film transistor (TFT). However, the application of gas sensors with this material is relatively less. Thus, in this study, three different metals (Pd, Pt, Au) were used to modify the surface of the IGZO thin film, respectively. Eventually, in our experiments, the studied devices have good sensing characteristics of hydrogen, ammonia, and formaldehyde. This study will also analyze the device structure, surface morphology and elemental composition of IGZO based gas sensors with scanning electron microscope (SEM), X-ray diffractometer (XRD), energy dispersion X-ray spectrometer (EDS), transmission electron microscope (TEM), and atomic force microscope (AFM).

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