本論文之研究主題係藉水熱法(hydrothermal growth, HTG)成長高品質之類單晶氧化鋅(Zinc oxide, ZnO)薄膜並進行垂直結構紫外光檢測器應用。利用本研究所開發n型類單晶ZnO薄膜與p型半導體材料氧化銅(Cuprous oxide, CuO)所得之異質p-n接面二極體，因具備寬能隙半導體材料之特性，極適合應用於紫外光感測器。為改善傳統水平式結構之ZnO紫外光感測器的缺點，如電流傳導路徑較長與嚴重之電流擁擠效應，本研究開發一種結合電鍍法製備金屬基板及超音波震盪機械式剝離之轉移基板技術，成功製備出垂直結構類單晶ZnO基紫外光檢測器。與現行紫外光感測器之製程相比，本研究方法具低溫製程(<100 oC)、大面積製作、成本低廉、製程步驟簡易等多項優勢，且相較於傳統水平結構之異質接面紫外光檢測器，本研究之垂直結構紫外光檢測器具極短之電流傳導路徑，除大幅降低串聯電阻與改善電流擁擠效應外，亦顯著提升元件於光能/電能轉換之效率。
本論文概分為三部份，第一部分為使用水熱法薄膜成長技術製備類單晶ZnO薄膜。於已濺鍍ZnO晶種層之藍寶石基板表面，進行ZnO薄膜之成長。材料分析與電性量測結果顯示，本研究所製備之ZnO薄膜具有單一晶格方向、高結晶性、高穿透率、高載子移動率及低電阻率之特性。
第二部份為基板轉移技術之開發。結合電鍍法製備金屬基板及超音波震盪機械式剝離技術，成功開發ZnO基板轉移技術。因水熱法製備之ZnO薄膜需使用較高成本之藍寶石基板，且此薄膜與晶種層之接面，具高缺陷密度與結構脆弱之問題，故本技術重點在於以金屬基板取代藍寶石基板，並透過超音波震盪施加應力於ZnO薄膜與晶種層之脆弱接面，除使ZnO薄膜與晶種層脫離外，可再藉蝕刻/研磨去除原晶種層上方具高密度缺陷之ZnO過度層，極有利於垂直結構光電元件之應用。
第三部分為以本論文所開發之基板轉移技術製備垂直結構ZnO/CuO異質接面紫外光感測器。與傳統水平結構之紫外光檢測器比較，因垂直式結構具較短之電流路徑，故展現出高整流比(JF/JR = 1.6×104, @±2 V)與較佳之光電特性(JUV/Jdark = 361)。此外，當元件經過高溫熱退火製程(氮氣環境下，退火500 oC)後，因元件缺陷之改善，可進一步將其光電響應(JUV/Jdark)大幅提升200%。
本研究以水熱法製備出具有高穿透率及良好結晶性之氧化鋅薄膜，結合電鍍與超音波震盪機械式剝離技術，製備出垂直結構n-ZnO/p-CuO異質接面紫外光檢測器，其優異的光能/電能轉換效率及快速響應速度，於紫外光檢測元件的發展將極具潛力。

Vertical ultraviolet photodetectors (UV-PDs) comprising of p-CuO and hydrothermally grown (HTG) n-ZnO heterojunction (HJ) through a simple substrate transfer process is demonstrated. The HJ were formed via radio frequency sputtering (RF) deposition of p-type CuO film onto the HTG ZnO film, which were subjected to thermal annealing in nitrogen ambient. An electroplated 60-m-thick nickel (Ni) layer was deposited onto the HJ-PD surface and the layer structure was removed from the original substrate through a sonicating bath process. The optoelectronic properties of vertical and lateral UV-PD under UV light (3 mW/cm2 at wavelength of 365 nm) are investigated and discussed. Owing to the much improved optoelectronic performances of the vertical structure allowing a relatively shorter current path and more uniform current distribution and without the adverse effect of seed layer encountered in conventional horizontal type device structure, a UV sensitivity (JUV/Jdark) as high as 687 has been obtained from the prepared vertical HTG-ZnO-based UV-PD.

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