本論文旨在利用水熱(hydrothermal, HT)成長方式於具蜂巢狀蝕刻孔洞陣列的圖案p型氮化鎵層(patterned p-GaN layer, PGL)上磊晶成長高品質單晶氧化鋅(ZnO)連續膜，探討其成長機制與其應用於n-ZnO/p-GaN異質結構發光二極體(heterojunction light emitting diodes, HJ-LEDs)和UV光感測器(ultraviolet photodetectors, UV-PDs)之應用與光電特性探討。主要研究內容可分為三大部份：
第一部分研究集中於有關使用HT成長方法於D5-L3 (接於D與L後之數字，分別表示D與L之尺寸，單位皆為μm)、d為0.2、0.5、1及1.5 μm的PGL進行磊晶成長ZnO連續膜之研究。實驗結果顯示，使用d =1 μm的PGL於蝕刻垂直洞壁所裸露的m-plane面積可提供較適化的ZnO晶體成核與磊晶成長，因此可成長出較高品質ZnO單晶膜。針對ZnO連續膜的可能成長機制與形成ZnO連續膜所使用的HT溶液中硝酸鋅(zinc nitrate hexahydrate, Zn(NO3)2·6H2O, ZNH)和六甲基四胺(hexamethylenetetramine, C6H12N4, HMT)之濃度為另一探討目標。實驗結果顯示，僅當["ZNH" ]" ≥ 75 mM" 以及["ZNH" ]"+" ["HMT" ]" ≥ 150 mM" 時，HT溶液可提供充足的ZnO分子於已終止側向磊晶成長(lateral epitaxial growth, LEG)的平坦六方塊外側m-plane上形成ZnO二次成長晶粒並產生新的梯級晶面，再度誘發LEG進行並且加速六方塊膜的連結與封口，應為形成ZnO連續膜的核心成長機制。
第二部份旨在探討於分別使用D5-L1、D3-L1及D2-L1的PGL以及90與70oC的HT製程溫度對於磊晶成長ZnO連續膜之影響。研究結果顯示，使用D2-L1的PGL在一階段3×-3× HT溶液及90 oC製程溫度下，可最有效磊晶成長出最佳品質ZnO單晶膜(~3.97 μm) 。宜注意，上述”3×”係表示3倍標準溶液濃度(1倍標準溶液濃度為25 mM)。此一結果可歸因D2-L1的PGL蝕刻孔洞於相同基板面積下，裸露出最大的洞壁m-plane面積及最小的洞底c-plane面積。然而由於ZnO晶體沿著c-軸/a-軸的相對成長速率隨著HT製程溫度的下降而降低，使用D2-L1及70 oC製程溫度、一階段15 h所得ZnO連續膜厚度可薄至1.8 μm。實驗亦發現，當 ZnO連續膜於N2氛圍下以500 oC進行30 min的熱退火處理後，可將近能帶輻射/深能階輻射的比值(NBE/DLE)由未退火前的0.26提高至16.02，除可修復ZnO連續膜內部原子鍵結達到降低膜內缺陷外，亦強化ZnO連續膜對於UV光之敏感度。
第三部份則旨在利用第二部份研究於D2-L1_70 oC、D2-L1_90 oC、D5-L1_70 oC、D5-L1_90 oC及無圖案p-GaN_70 oC所分別製作的n-ZnO/p-GaN異質結構元件，分別命名為試片-A、B、C、D及E，分別探討其在發光二極體和UV感測器應用之光電特性。於發光二極體的光電特性部份，從電致發光(EL)光譜分析顯示出分別在413 nm有一明顯的紫-藍光發射訊號以及在387 nm有一較弱的紫外光發射訊號。五種元件中以試片-A具有最強的EL光發射強度以及最佳UV光響應特性(JUV/Jdark=508倍、上升/下降時間分別為4/<1秒@V=-1 V及以365 nm波長與3 mW/cm2功率照射)，主要應可歸之於試片-A使用D2-L1的PGL上以70 oC製程溫度進行15 h的HT成長製程，形成ZnO連續膜的膜厚最薄(~1.8 μm)，具有最小的串聯電阻及最佳的整流特性，並於相同面積下，ZnO與PGL所裸露m-plane有最大的接合面積。
本研究利用HT成長方法於PGL上磊晶成長高品質單晶ZnO連續膜，除釐清二次成長晶粒並產生新的梯級晶面，再度誘發LEG進行並且加速六方塊膜的連結與封口，應為ZnO薄膜的成長機制外，於薄膜材料品質方面，相較於直接在c-plane GaN層上所成長出包覆較多晶界及缺陷的ZnO奈米柱膜，具有較高品質的晶體結構，且所製備異質結構元件亦展現出較佳的光電特性。本研究所開發於PGL成長ZnO連續膜的技術，與傳統MOCVD或MBE等磊晶技術相比，具有製成簡易與低成本之優勢，預期未來如能進一步提升水熱法之操作穩定性，將有助於進一步擴展本技術於光電科技產業之應用。

In this study, high-quality single crystalline ZnO film were grown on PGL by hydrothermal growth (HTG) method, and its applications on light emitting diodes (LEDs) and ultraviolet photodetectors (UV-PDs) with ZnO film/p-GaN heterojunctions (HJs) were demonstrated. In experiments, PGLs with depth of etching holes (d= 1-μm) in a honey comb array were used as a template for epitaxial growth ZnO crystal. It is found that a more efficient and epitaxial growth of a higher quality ZnO single-crystal film due to the exposed m-planes on the vertical walls of etching holes provide much better nucleation and making possible epitaxial growth of ZnO crystals. For case with "ZNH ≥ 75 mM" and "ZNH+HMT ≥ 150 mM" , sufficient ZnO molecules could cuase strong, secondary growth on the outer side of the hexagonal {101 ̅0} m-plane to initiate further lateral growth. The occurrence of SLG stages during the HTgrowth process is a crucial link between hexagonal ZnO rings/prisms (or NRs/NWs) and continuous ZnO film. Effects of the diameter (D) and space (L) of PGL and HT process temperatures of 90 and 70 oC on the growth and quality of ZnO film were investigated. Our results show that the use of PGL with D2-L1 and 3×-3× HT solution at 90 °C HT process temperature could facilatate the epitaxial growth of ZnO single crystal film with the best quality. However, using D2-L1 and 70 °C HT process temperature, the thickness of ZnO films can be minimized to be about 1.8-μm. Furthermore, the ratio of near-band radiation / deep-level radiation (NBE / DLE) was seen being increased from 0.26 to 16.02 after annealing at 500 oC for 30 min in N2 ambient. Applications of the prepared ZnO film/p-GaN heterostructures in LEDs and UV-PDs and their photoelectric performance were sexamined and demonstrated. The EL spectra consisted of a dominant violet-blue emission peak centered at about 413 nm and UV emission peaks at about 387 nm. Among the five types of samples based on ZnO film on PGL, the sample-A exhibited the strongest integrated EL intensity and the UV sensitivity (JUV/Jdark) is 508-fold with a response time and recovery time of 4 seconds and of less than 1 second.

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