本論文主要探討利用一種非真空化學氣相沉積法 - 超音波噴霧熱裂解沉積法製備氧化鋅鎵薄膜並應用於太陽盲光檢測器。超音波噴霧熱裂解沉積法是一種非真空、成本低廉、製程時間短且易於調變前驅物濃度以及透過調變前驅物實現參雜之薄膜沉積技術。在本論文中，我們使用該技術沉積氧化鋅鎵薄膜，並進一步將其應用於製作兩種結構的太陽盲光檢測器，分別為金屬-半導體-金屬(MSM)以及pN光電二極體。
我們分別研究氧化鋅鎵薄膜在氧氣、氮氣及空氣中以800°C退火一個小時，將其製作成MSM結構光檢測器元件，透過元件電性分析得出以下結論:
在三種環境下退火的元件分別有不同的特性，相較於沒退火的元件，在氧氣環境下退火的元件由於氧缺陷被填補，光電流以及暗電流都有明顯的下降，在250奈米(UVC)波段照射以及偏壓5伏特仍有著不錯的光響應度0.148安培/瓦，動態響應為上升時間=9.654秒, 下降時間=0.544秒；在氮氣退火下，暗電流維持在10-12安培左右，光電流比起氧氣退火元件約高於一個數量級，也使得光響應度提升到了2.6安培/瓦，響應時間為上升時間=8.959秒, 下降時間=0.457秒；在空氣退火下，暗電流同樣維持在10-12安培左右，光電流提升到了約10-6安培，使得光響應度更是提升到了25.92安培/瓦，響應時間為上升時間=6.551秒, 下降時間=0.653秒。特別的是，以空氣退火的元件在深紫外光/紫外光(RUVC/RUVA)拒斥比高達2.01*105，展現出優異的深紫外光-紫外光選擇性。
由以上我們得出氧化鋅鎵薄膜在空氣環境下退火後，有著良好的薄膜品質而帶來優異的電性表現，因此我們以此作為製作pN光電二極體的N型材料，接著以射頻濺鍍(RF sputtering)沉積氧化鎳作為光電二極體的P型材料，成功製作出有整流特性以及具有光響應的光電二極體，由於具有內建電場，響應時間更進一步降低至上升時間=5.99秒, 下降時間=0.37秒。
在本論文中，我們成功以超音波噴霧熱裂解沉積法製備而成的氧化鋅鎵薄膜相較於現有的其他沉積方法而言，具有低成本、製程快速且可大面積沉積，再藉由高溫退火，即可製作出高品質的氧化鋅鎵薄膜。因此，我們認為超音波噴霧熱裂解沉積法在工業應用有一定的優勢與潛力。

This thesis mainly investigates the zinc gallium oxide thin films using a non-vacuum chemical vapor deposition method - ultrasonic spray pyrolysis deposition, and then applies them to solar-blind photodetectors. Ultrasonic spray pyrolysis deposition is a non-vacuum, low cost, short process time, easy to adjust the concentration of the precursor and realize doping by modifying the precursor. In this thesis, we use this technique to deposit ZnGa2O4 thin films and further apply it to the fabrication of two structures of solar-blind photodetectors: metal-semiconductor-metal (MSM) and pN photodetectors.
We studied the annealing of ZnGa2O4 films in oxygen, nitrogen, and air at 800°C for one hour and then fabricated MSM structure photodetectors, and obtained the following conclusions from the electrical analysis of the devices:
The devices annealed in the different ambiences have different characteristics. Compared to the unannealed device, the oxygen-annealed device showed a significant decrease in photocurrent and dark current due to the filling of oxygen defects. It exhibits responsivity of 0.148A/W illuminated at 250nm and biased at 5V with a response time of 9.654s/0.544s. Under nitrogen annealing, the dark current is maintained at about 10-12 A and the photocurrent is about one order of magnitude higher than that of the oxygen annealed device, which also increases the responsivity to 2.60 A/W, with a response time of tr= 8.959s and tf = 0.457s. The responsivity is 25.92 A/W, with a response time of tr= 6.551s and tf = 0.653s. In particular, the air annealed device has a high rejection ratio of 2.01*105 for DUV/UV (RUVC/RUVA), demonstrating excellent DUV/UV selectivity.
From the above, we concluded that the zinc gallium oxide thin films have excellent electric characteristics after annealing in the air due to their good film quality. Therefore, we used it as the n-type material for the pN photodetector, and then nickel oxide was deposited by RF sputtering as the p-type material for the pN photodetector, and a photodetector with rectification characteristics and photoresponse was successfully fabricated. With the built-in electric field, the response time was further reduced to tr=5.99s and tf =0.37s.
In this thesis, we successfully used the ultrasonic spray pyrolysis deposition method to deposit high-quality ZnGa2O4 films with low cost, fast process, and large deposition area compared to other existing deposition methods. Therefore, we believe that ultrasonic spray pyrolysis deposition has some advantages and potential for industrial applications in the future.

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