本論文主要探討利用超音波霧化熱裂解法沉積氧化鎵鋅應用於紫外光檢測器。在眾多沉積氧化鎵鋅薄膜製程中，我們選擇一種非真空環境下即可完成且低成本之製作方法: 超音波噴霧熱裂解沉積法，並將此製程分別應用於兩種紫外光檢測器上，分別為金屬-半導體-金屬（金-半-金）、PN異質接面結構。
為了瞭解氧化鎵鋅之吸收度、折射係數、消光係數、結晶方向、表面粗糙度、氧空缺、化學組成、薄膜厚度，本研究中使用（一）分光光譜儀、（二）椭圓偏光儀、（三）X-射線繞射分析、（四）原子力顯微鏡、（五）光致螢光光譜、（六）化學分析影像能譜儀、（七）掃描式電子顯微鏡、（八）顯微拉曼光譜儀。
在瞭解薄膜之材料分析後，將超音波噴霧熱裂解沉積技術應用於（一）金-半-金與（二）PN異質接面結構紫外光檢測器上成長氧化鎵鋅主動層，並以低成本的溶膠凝膠法成長氧化鎳主動層應用於PN異質接面結構紫外光檢測器。為了探討不同鎵含量造成的特性差異，因此成長了三種氧化鎵鋅薄膜。在這三個元件中，鎵與鋅莫耳比為0.2比0.8時，我們得到最佳的金-半-金紫外光檢測器之特性。因此，我們使用此比例的N型氧化鎵鋅製作PN異質接面紫外光檢測器。
PN紫外光檢測器是由P型半導體與N型半導體所組成。我們選擇了氧化鎳與氧化鎵鋅作為主動層材料，並分別使用溶膠凝膠法與超音波霧化熱裂解法成長。為了提高PN紫外光檢測器其特性，我們旋轉塗佈一層有機P型材料PEDOT:PSS在PN紫外光檢測器上。為了探討PN紫外光檢測器的特性，我們做了很多元件分析，包含電流電壓特性，光譜響應量測與感測度。有PEDOT:PSS的PN紫外光檢測器在暗電流、光響應度、紫外光可見光響應比與感測度上的特性較無PEDOT:PSS的PN紫外光檢測器來得優異。在這些特性之中，其感測度高達十的十四次方。
在本論文中，超音波噴霧熱裂解沉積法可以成長出高品質的氧化鎵鋅薄膜。最後，此技術無須在真空環境下製作且所需成本較低，在實際工業應用上極具潛力。

The research mainly investigates on the GaZnO-based ultraviolet (UV) photodetectors (PDs) by using ultrasonic spray pyrolysis technique. Among GaZnO thin film deposition methods, ultrasonic spray pyrolysis deposition (USPD) which is a non-vacuum and low cost approach is used to fabricate the gallium zinc oxide active layer. Furthermore, this technique is applied to two different structured UV PDs, including metal-Semiconductor-metal (MSM) and PN heterojunction structures.
In order to know absorbance, refractive index and extinction coefficient, crystal directions, surface roughness, oxygen vacancies, composition of chemical elements and the thickness of the oxide layer, the (1) UV/VIS/NIR spectrophotometer, (2) Ellipsometry, (3) X-ray diffraction (XRD), (4) Atomic force microscopy (AFM), (5) Photoluminescence spectrometer (PL), (6) Electron spectroscopy for chemical analysis (ESCA), (7) Scanning electron microscope (SEM) and (8) Microscopes Raman spectrometer are adopted in this research.
After the material analysis of the GaZnO film. the USPD technique is used to grow the GaZnO active layer of the MSM UV PDs and the PN heterojunction UV PDs, and the low-cost sol-gel is applied to grow the NiO for active layer of the PN heterojunction UV PDs. In order to investigate the characteristics of the different Ga contents in the MSM UV PDs, three GaZnO films of the different Ga contents are grown, which are Ga0.1Zn0.9O, Ga0.2Zn0.8O and Ga0.3Zn0.7O. Among three devices, when the molar ratio of Ga to Zn is maintained at 0.2 to 0.8, we can get the better performance of the MSM UV PD. Therefore, we use Ga0.2Zn0.8O for the n-type material to fabricate PN heterojunction UV PDs.
PN UV PD mainly consists of a p-type semiconductor and an n-type semiconductor. The NiO and GaZnO grown by sol-gel and USPD are used as the active layers in the PN structures. In order to improve the performance of the PN UV PD, PEDOT:PSS was spin-coated on the NiO/Ga0.2Zn0.8O UV PD. Moreover, PEDOT:PSS is an organic p-type material. In order to investigate the characteristics of PN UV PDs, we do many analyses of the devices, including current-voltage characteristics, spectral response measurement and detectivity of PDs. The dark current, responsivity, UV-to-visible rejection ratio and detectivity of the PN UV PDs with PEDOT:PSS are better than those of the PN UV PDs without PEDOT:PSS. Among the performances, the detectivity of the PN UV PDs with PEDOT:PSS is up to 1014 Jones at -2 V.
In this thesis, the USPD technique makes good quality of GaZnO film. Last but not least, the technique is non-vacuum and low cost fabrication methods which is potential in the industrial applications.

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