本論文主要探討利用超音波噴霧熱裂解法沉積氧化鎂鋅應用於紫外光檢測器。超聲波噴霧熱裂解沉積法是一種成本低廉、非真空、製成時間短且易於調變前驅物參雜濃度之薄膜沉積技術。我們將該技術應用於四種紫外光檢測器上，分別為金屬-半導體-金屬、雙波段、PN以及NPN結構。此外，我們藉由將金屬銀奈米粒子添加至紫外光檢測器之吸收層以改善其性能。
為了瞭解氧化鎂鋅薄膜之薄膜厚度、化學組成、結晶性、結晶方向、氧空缺、折射係數、消光係數、材料能隙、表面粗糙度及光透射率，在本研究中使用（一）掃描式電子顯微鏡、（二）穿透式電子顯微鏡、（三）X-射線光電子能譜學、（四）椭圓偏光儀、（五）光致發光、（六）X-射線繞射分析、（七）原子力顯微鏡、（八）霍爾量測、（九）分光光譜儀。
首先，我們使用掃描式電子顯微鏡拍攝樣品的俯視圖以確認氧化鎂鋅薄膜中存在銀奈米粒子。 接著我們採用XPS分析分別確定氧化鎂鋅薄膜有無存在奈米粒子之氧空缺比例變化，並與隨後的光致發光測量獲得一致性的結果。最後，我們透過這些分析確認了紫外光檢測器性能之提升主要由銀奈米粒子所貢獻。
在瞭解薄膜之材料分析後，我們製作了雙波段紫外光檢測器，可應用於紫外光A以及紫外光B之寬波段檢測。 除了雙波段紫外光檢測器之性能隨著不同銀奈米粒子位置而提升外，我們還探討不同吸收層厚度對雙波段紫外光檢測器之影響。
在N-P-N結構的部分，我們製作了由氧化鋅、氧化鎳以及氧化鎂鋅組成之紫外光檢測器。 我們藉由多項元件分析分別比較N-P-N結構與P-N結構製備之紫外光檢測器的特性，包括電流電壓特性、光譜響應量測與感測度等，由此我們證實了N-P-N結構可以有效地增強紫外光檢測器的電性表現。
在本論文中，我們以超音波噴霧熱裂解沉積法製備的氧化鎂鋅紫外光檢測器相對於其他沉積方法而言，具有低成本且製程快速的優點。而我們也透過控制沉積速率成功地實現氧化鎂鋅奈米結構之成長。因此，我們認為超音波噴霧熱裂解沉積法在工業的應用上極具優勢與潛力。

This thesis mainly investigates on the magnesium zinc oxide-based ultraviolet (UV) photodetectors (PDs) by ultrasonic spray pyrolysis deposition. Ultrasonic Spray Pyrolysis Deposition (USPD) is a thin film deposition technology which is low cost, non-vacuum, rapid process and easy to carry out precursor doping, is used to fabricate the magnesium zinc oxide active layer. In the thesis, this technique is applied to four different structure of UV PDs, including metal-semiconductor-metal (MSM), dual-wavelength, P-N and N-P-N structures. In addition, the metal (Ag) nanoparticles were added into the absorption layer of ultraviolet photodetectors to improve the performances of the photodetectors.
In order to know the thickness, chemical composition, crystallinity, crystal directions, oxygen vacancies, refractive index, extinction coefficient, material energy bandgap, surface roughness and transmittance of magnesium zinc oxide film, the (1) Scanning electron microscopy, (2) Transmission electron microscope, (3) X-ray photoelectron spectroscopy, (4) Ellipsometry, (5) Photoluminescence, (6) X-ray diffraction, (7) Atomic force microscope, (8) Hall measurement and (9) UV-VIS-NIR spectrophotometer analysis are adopted in this research.
First, a top view section images of the samples were photographed using a scanning electron microscope to confirm Ag nanoparticles in MgZnO film. Then, we employed XPS analysis to confirm the oxygen vacancies proportion of MgZnO film with and w/o nanoparticles, and the result was consistent with the subsequent photoluminescence measurements. By above analyses, we confirm that the enhanced performance of ultraviolet photodetectors is attributed to Ag nanoparticles.
After the material analysis of the MgZnO film, we made the dual-wavelength ultraviolet photodetectors, which could be applied wide ultraviolet wavelength detection including UVA and UVB region. The performance of dual-wavelength ultraviolet photodetector increases with the different positions of Ag nanoparticles. Besides, we also discuss the effect of the different absorption layers thickness for dual-wavelength ultraviolet photodetector.
In the part of the N-P-N structure, we fabricated the ultraviolet photodetector consisted of ZnO, NiO and Mg0.4Zn0.6O. We compare many analyses of the ultraviolet photodetectors fabricated by this structure with that fabricated by the P-N structure, including current-voltage characteristics, spectral response measurement and detectivity. Thus, we confirm that the electrical performance of ultraviolet photodetector could be effectively enhanced by the N-P-N structure.
In this thesis, the magnesium zinc oxide ultraviolet photodetectors fabricated by the ultrasonic spray pyrolysis deposition have the advantages of the low cost and rapid process relative to other deposition methods. Moreover, we have also successfully grown the MgZnO nanostructures by controlling the deposition rate. We believe that the ultrasonic spray pyrolysis deposition has great potential and advantages in the industrial applications.

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