本篇論文主要探討以超音波噴霧熱裂解法沉積氧化鋅薄膜進而應用於紫外光檢測器。超音波噴霧熱裂解法為一種成本低廉、非真空環境成長、製程迅速且便於進行前驅物摻雜的ㄧ種薄膜沉積技術。透過製作金屬-半導體-金屬以及光二極體兩種形式的紫外光檢測器以及相關材料分析所得到的數據，認為此一技術在成長金屬氧化物薄膜的應用上具有極高的產業應用價值。
為了瞭解氧化鋅薄膜的厚度、化學組成、折射係數、材料能隙及結晶性，在本研究中使用了(一)掃描式電子顯微鏡、(二)化學分析電子儀、(三)橢圓偏光儀、(四)光致發光、(五)X-射線繞射分析。首先，運用掃描式電子顯微鏡拍射試片的橫切面用以確認氧化鋅薄膜的厚度，再透過化學分析電子儀確認所形成的薄膜為氧化鋅，接著運用橢圓偏光儀確認氧化鋅材料的折射係數與消光係數，並將隨後的光致發光量測結果加以對比獲得一致性的結果，最後透過X-射線繞射分析確認採用超音波噴霧熱裂解法藉由慢速成長可得到高結晶性的氧化鋅薄膜。
在確認氧化鋅薄膜的基本性質後，首先我們將此一薄膜利用金屬-半導體-金屬的形式製作了紫外光檢測器，運用相關研究分析所得到的結論，製作了極薄氧化鋅薄膜的金屬-半導體-金屬之紫外光檢測器，於偏壓5伏特的情況下，黑箱量測所得的暗電流低至約44皮安培；同時，在波長340奈米，強度為10微瓦的紫外光照射下，得到約0.14微安培，光暗電流比可達3185倍。
在光二極體的部分，我們先製作了氧化鎳/氧化鎂鋅/氧化鋅之p-i-n光二極體，搭配以化學溶液沉積法製作之氧化鋅奈米柱，於偏壓負0.5伏特，紫外光波長為370奈米照射時，光響應為0.19安培/瓦，光暗電流比為169.91。基於此元件的製作經驗，我們更改了二極體結構的布局並且採用重摻雜p型矽基板與氧化鋅搭配，製作了於正負2伏特之間，整流比可達2萬倍的異質接面二極體。相比於氧化鎳/氧化鎂鋅/氧化鋅之p-i-n光二極體，結構的重整使得暗電流大幅下降至0.4奈安培於偏壓為負2伏特時，此外，於偏壓負4伏特時，對370奈米的紫外光光響應仍有0.11安培/瓦，光暗電流比(370奈米光電流與黑箱量測暗電流之比)可達896.07倍，且紫外光/可見光拒斥比(370奈米與400奈米之光電流比)達112.39倍，罕見於相似之研究應用。
在本篇論文中，以超音波噴霧熱裂解法所製作的氧化鋅紫外光檢測器，相對於其他方式成長的氧化鋅具有成本優勢或是時間優勢或者兩者皆有，且實際製作之光檢測器，其操作性能相對於其他技術或有高或有低，應屬於實驗誤差，因此綜合元件特性、設備成本、製程時間等等因素考量，應用於實際量產有極大的潛力與優勢。

This thesis mainly investigates the zinc oxide thin film deposited by ultrasonic pyrolysis, and applies to ultraviolet photodetectors. Ultrasonic Spray Pyrolysis is a thin film deposition technology which is low cost, non-vacuum, rapid process and easy to carry out precursor doping. Through the fabrication of metal-semiconductor-metal and photodiode two forms of UV photodetector and related materials analysis results, we believe that this technology in the growth of metal oxide films application has a very high industrial value.
In order to understand the thickness, chemical composition, refractive index, material energy gap and crystallinity of zinc oxide thin films, the (1) scanning electron microscopy, (2)chemical analysis electron meters, (3) ellipsometer, (4) photoluminescence and(5) X-ray diffraction analysis are adopted in this research. First, a cross section of the sample was photographed using a scanning electron microscope to confirm the thickness of the zinc oxide film. And then XPS analysis are employed to confirm the ZnO films. Then the ellipsometry was used to confirm the refractive index and the extinction coefficient of the zinc oxide material, and the results of the subsequent photoluminescence measurements were consisted with this results. Finally, the X-ray diffraction analysis was carried out to confirm the high crystalline zinc oxide film can be obtained from ultrasonic spray pyrolysis deposition by slow growth method.
After confirming the basic properties of the zinc oxide film, we first made the metal-semiconductor-metal UV photodetectors with ultra- thin ZnO film. The dark current measured by the black box is as low as about 44 picobar at a bias voltage of 5 V. At the same time, About 0.14 µA was measured under the illumination of 340 nm UV light with intensity of 10µW, photo-to-dark current ratio up to 3185 times.
In the part of the photodiode, we first made the nickel oxide/magnesium zinc oxide/zinc oxide pin photodiode, with the zinc oxide nanorod arrays by chemical bath deposition. At the bias voltage of -0.5V, illumination under 370nm UV light, the responsivity is 0.19 A/W, and the photo-to-dark current ratio is 169.91.
Because the dark current of the previous photodiode is large, We changed the layout of the diode structure. By the combination of heavily doped p-type silicon with zinc oxide, we fabricated a hetero-junction photodiode with the rectification ratio of up to 20,000 times between ±2V. The structural reorganization caused the dark current to drop significantly to 0.4 nA at a bias voltage of -2V. At bias voltage of -4V, the responsivity is 0.11 A/W, the ratio of photo-to-dark current ratio (370 nm photocurrent and dark current ratio) is 896.07 times, and the ultraviolet light / Visible light rejection ratio (370 nm and 400 nm) is 112.39 times, which is rare in similar research applications.
In this thesis, the zinc oxide UV photodetectors produced by the ultrasonic spray pyrolysis deposition has the low cost or the time-saving advantage relative to other ways of growing zinc oxide. By the comprehensive consideration, we believe that the ultrasonic spray pyrolysis deposition used in mass production has great potential and advantages.

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