氧化鋅是近年來受到高度關注並已投入大量研究的半導體材料之一。它本身具有多項優點，包含寬且直接的能隙(室溫下約3.37電子伏特)及大的激子束縛能(室溫下約60毫電子伏特)，加上其在熱穩定性及化學穩定性上都有相當不錯的表現。因此，相當適合應用在光電元件上。但，在製備元件的半導體製程中，溫度的上升是個不可避免的情況。而熱效應對於半導體本身的特性具有相當程度的影響。因此，本論文主要著重於以氧化鋅薄膜為基底之金半金紫外光檢測器的製備，與光檢測器經由熱處理藉以模擬半導體製程的升溫現象後所產生影響之研究。
首先，利用共濺鍍系統在石英玻璃基板上沉積出一層氧化鋅主動層(厚度約100奈米)。此外，也取出部分樣品並在基板與氧化鋅主動層間利用電子束蒸鍍機以蒸鍍方式插入不同厚度的銀金屬層(厚度約2奈米與5奈米)。之後將製備完成的三種樣品(氧化鋅、氧化鋅/2奈米銀層、氧化鋅/5奈米銀層)送入水平式爐管中進行熱回火處理。接著，所有製備完成的六組樣品，再次利用電子束蒸鍍機蒸鍍上鎳/金指叉狀電極以形成蕭基接觸的金半金光檢測器，並測量光電特性。此外，也對所有樣品做物性與光性的分析。
在尚未回火處理的元件中，未有奈米銀層的氧化鋅光檢測器拒斥比為94。而嵌入2nm銀界面層後拒斥比上升至113，但當銀界面層厚度增至5奈米後，拒斥比卻反而降至65，顯示為增加氧化鋅光檢測器的光檢測特性，嵌入之奈米銀層厚度是具有限制的。
而經由回火處理後，純氧化鋅光檢測器拒斥比會由未回火前的94，驟降為4，失去了對光的選擇性。但拒斥比在嵌入2奈米與5奈米銀層經由回火處理後分別回復成73與29，顯示氧化鋅光檢測器在嵌入氧化銀顆粒後可以補償恢復回火後本身元件特性以及增強對於光的選擇性，而這些氧化銀奈米顆粒是經由插入之奈米銀層經由回火過程而相轉換形成。

In the recent years, ZnO is one of the popular semiconductor materials and has been highly attended and researched. It has a large number of advantages, such as wide and large band gap (~3.37eV at room temperature) and large excitons binding energy (~60meV at room temperature). Besides, it has good performance in the thermal and chemical stability. So, it is suitable for applying in optoelectronics. But, in the semiconductor processes to fabricating the devices, the rise of temperature is unavoidable. And the thermal effect can seriously affect the characteristics of the semiconductors. Therefore, this thesis mainly focuses on the fabrication of ZnO-based metal-semiconductor-metal ultraviolet photodetectors, and the effects which were made by thermal process on the annealed photodetectors for simulating the temperature-rising situation in semiconductor process.
At first, we deposited the ZnO active layers (the thickness was about 100nm) on quartz substrate by co-sputtering system. Besides, we took some of them out and inserted different thickness of Ag layer (the thickness were about 2nm and 5nm) between the substrates and ZnO active layers by electron beam evaporator. Then, the three samples (ZnO, ZnO/2nm Ag, ZnO/5nm Ag) were sent into the horizontal furnace for annealing process. Continuing, the six samples were sent into electron beam evaporator for depositing Ni/Au interdigital electrodes to form the Schottky contacts in metal-semiconductor-metal photoconductor, and measured the optoelectronic characteristics. Furthermore, we took physical and optical analysis, too.
In the devices without annealing, the responsivity of ZnO photodetector without Ag nano-layer was 94. With 2nm Ag inter-layer, the responsivity was raised to 113. But, when the thickness of Ag inter-layer was increased to 5nm, the responsivity was decreased to 65. It was obvious that in order to increase the photo-detect characteristics of the ZnO photodetector, the thickness of the inserted Ag nano-layers was limited.
After annealing process, the responsivity of ZnO photodetector without Ag nano-layer is decreased to 4 from 94 which was the non-annealed one, and it lost its selection of the incident light source. But the responsivities recovered to 73 and 29 for inserted 2nm and 5nm Ag nano-layers, respectively. It shows that the ZnO photodetectors with embedded Ag2O nanoparticles could compensate the devices characteristics after annealing and enhanced the selection of the incident light source, and these Ag2O nanoparticles were transferred from the embedded Ag nano-layres.

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