本論文旨在藉由水熱法(hydrothermal growth, HTG)進行類單晶之氧化鋅(ZnO)薄膜選擇性成長，以ZnO薄膜為基材搭配其它p型半導體材料（例如：p型氮化鎵(p-GaN)、p型氧化鎳(p-NiO)），進而製備異質接面結構之發光二極體以及紫外光檢測器。本研究所採用HTG技術具製程環境低溫低壓、成長時間短與元件製作成本低廉等優點，相較於其他ZnO奈米結構所製備之異質接面結構二極體，本研究之ZnO薄膜結構具備較大接面面積，與較高之機械應力，亦可避免ZnO接面製作時，若未先以絕緣材料填塞於ZnO奈米結構之間，極易發生上下電極或p型材料短路之缺點。
本論文之研究工作概分為三部份，第一部分為利用水熱法製程，於p-GaN磊晶表面以及已濺鍍ZnO晶種層之藍寶石基板表面，分別進行ZnO薄膜之成長，並藉由X-光繞射(XRD)、穿隧式電子顯微鏡(TEM)、可見光穿透率量測儀及霍爾量測機台進行分析，證實本研究所製備之ZnO薄膜具有高結晶性、高穿透率、高載子移動率及低電阻率之特性。
第二部分集中於p-GaN磊晶層上成長ZnO薄膜及其元件應用之研究工作。經分別沉積p型及n型歐姆接觸金屬電極於p-GaN薄膜與所成長之n-ZnO薄膜，完成n-ZnO/p-GaN異質接面結構二極體之製備並進行發光二極體以及紫外光檢測器之光電特性量測分析與探討。由實驗結果顯示，於發光二極體之特性上，電致發光之光譜圖於393 nm與410 nm有明顯峰值，整體發光強度與注入電流大小成正相關；於紫外光檢測器之特性上，紫外光（波長：365 nm，光強度：3 mW/cm2）照射下有447倍 (JUV/Jdark)之光響應，響應時間與回復時間分別為7秒及1秒。
第三部分研究工作集中於藍寶石基板上成長ZnO薄膜以及其與p-NiO濺鍍薄膜之元件應用研究。於所成長ZnO薄膜上濺鍍沉積一層不同厚度之p-NiO薄膜後，沉積p型及n型歐姆接觸金屬電極，進行n-ZnO/p-NiO異質接面結構二極體之製備並進行紫外光檢測器之光電特性量測及數據分析。實驗結果顯示，此元件於p-NiO薄膜厚度為600 nm展現出高整流比之電流特性。於紫外光（波長：365 nm，光強度：3 mW/cm2）照射下有695倍(JUV/Jdark)之響應，響應時間與回復時間分別為57秒及13秒。
本研究以水熱法製備出具有高結晶性及高穿透率之ZnO薄膜，並分別與p-GaN與p-NiO成功製備異質結構光電元件，具優異光電特性及高響應能力，極具應用潛力，預期於本研究所提出有關水熱法成長之高結晶性ZnO薄膜及其於光電元件之應用將可對光電產業提供助益。

In this study, quasi-monocrystalline ZnO film was fabricated by hydrothermal growth (HTG) method, and its applications on light emitting diodes (LEDs) and ultraviolet photodetectors (UV-PDs) with n-ZnO/p-GaN and n-ZnO/p-NiO heterojunctions (HJs) were demonstrated. Strong UV-blue emission from the n-ZnO/p-GaN HJ-LED with a dominant peak at 393 nm and a small sub-peak at 410 nm without defect-related emissions in the visible region were observed from electroluminescence (EL) spectra. The measured current density-voltage (J-V) curves in darkness shows that UV-PDs with n-ZnO/p-GaN and n-ZnO/p-NiO HJs have rectifying current-voltage characteristics. The UV-PDs of n-ZnO/p-GaN HJ and n-ZnO/p-NiO HJ possessed superior UV light (3 mW/cm2 at 365 nm) sensitivity of 447-fold and 695-fold, and weaker visible light sensitivity of 1.8-fold and 11-fold, respectively.

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