本論文之研究主題係藉由水熱法(hydro-thermal growth, HTG)進行類單晶之氧化鋅薄膜之選擇性成長，以氧化鋅薄膜為基材搭配其它P型半導體材料(例如:氧化亞銅、氧化鎳)，進而製備出異質接面結構之UV光感測器，本研究方法具有低溫低壓製程、製程時間短、元件製作成本低廉亦可避免傳統使用氧化鋅奈米線作為UV感測元件之絕緣製程(此製程技術複雜耗時，導致元件成本提高)、較大接面面積與較高之材料應力(與奈米結構比較)。本論文研究工作概分為三部份，第一部分為利用水熱法製程，於晶種層AZO表面進行出氧化鋅薄膜成長，並藉由XRD、TEM、穿透率量測及霍爾量測，證實此薄膜具有高結晶性、高穿透率低、高載子移動率及低電阻率之特性。第二部分將已製備氧化鋅薄膜之ITO玻璃基板表面，沉積p-Cu2O薄膜，進行HTG-ZnO/p-Cu2O異質接面結構的UV光感測器研製與光電特性分析。實驗結果顯示，擁有500 nm厚度p-Cu2O薄膜的異質結構UV光感測器可展現出高整流比之光電流特性，與利用濺鍍機沉積氧化鋅薄膜所製備之異質結構紫外光感測元件相較下，具有較佳的響應特性。此元件經過熱退火製程(氮氣下退火600oC)後，於UV光波長365 nm照射下有55.6倍(IUV/Idark)之響應，響應時間與回復時間分別為15秒及10秒，漏電流為0.06 uA/cm2 (Jr @-1 V)。第三部分係以與第二部份相同之製程進而製備出n-ZnO/p-NiO之異質結構UV光感測器，此元件在p-NiO厚度為500 nm時，具有最佳的光電流特性，與利用濺鍍機沉積氧化鋅薄膜所製備之異質結構紫外光感測元件相較下，亦具有較佳的響應特性。且此元件經過熱退火製程(氮氣下退火600oC)後，於UV光波長365 nm照射下有260.3倍(IUV/Idark)的響應，響應時間與回復時間分別是2.5秒及7秒，漏電流為0.19 uA/cm2 (Jr @ -1 V)。與n-ZnO/p-Cu2O異質結構UV光感測器相較下，ZnO/p-NiO異質結構UV光感測器擁有較佳響應特性、較短之響應時間及回復時間，此可能因氧化亞銅能隙寬度較窄(2.1 ev)以至量子效率較低(轉為熱能-歐傑效應)，以及氧化亞銅之載子移動率較低所致。
本研究以HTG製備出具有高穿透率及良好結晶性之氧化鋅薄膜，並分別與p-NiO與p-Cu2O成功製備異質結構UV光偵測器元件，光電特性優異及快速響應能力，於UV光偵測器元件應用上具有潛力。

In this study, the use of a nanocrystalline ZnO film grown by hydrothermal growth (HTG) method for the fabrication of p-Cu2O/n-ZnO and p-NiO/n-ZnO heterojunction (HJ) ultraviolet photodetectors (UV-PDs) are proposed and demonstrated. The HJs were formed via radio frequency (rf) sputtering deposition (SD) of p-type Cu2O or NiO film onto the HTG ZnO film, which were subjected to thermal annealing in nitrogen ambient. Effect of the annealing temperature on the photoluminescence spectra of HTG-ZnO film was investigated. Comparisons between UV-PDs based on HTG and SD ZnO films were made. The measured current density-voltage (J-V) curves in darkness show that both the prepared p-Cu2O/n-ZnO and p-NiO/n-ZnO HJs have rectifying current-voltage characteristics. The optoelectronic properties of the two types HJs with Cu2O thickness in the range of 250-750 nm and NiO thickness in the range of 250-750 nm under UV (365 nm) light intensities (3 mW/cm2) were examined and discussed. Effect of thermal annealing on the sensing performance of the two types of HJs under UV (365 nm and 254 nm in wavelength and 3 mW/cm2 in power density) and visible light light irradiation (25 mW/cm2 in power density) were studied and discussed.
The p-Cu2O/n-ZnO and p-NiO/n-ZnO HJs possesses superior UV light (365 nm) sensitivity (about 55.6 and 260.3 times) and weaker visible light sensitivity (about 3.6 and 2.3 times) after thermal annealing at bias of -1 V.

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