氧化鋅(Zinc oxide, ZnO) 是一種n型直接能隙半導體材料，具有寬能隙(3.3eV)及顯著的C軸優選成長方向而有優異壓電及壓光效應，因此適合做為奈米發電機、發光二極體、或紫外光感測器等光電元件。近年來臭氧層破洞與氣候變遷，導致深紫外光波段的UV-A和UV-B 影響著地球的整個生態系統，對人類來說，若不做好防曬及防護措施，長期照射下，將對於人體健康亦有所危害，因此需製備UV-B(320~280nm)紫外光感測器。
本實驗透過元素合金化提升氧化鋅材料的能隙(3.3eV)，使用氧化鎂鋅的材料系統能有效調整能隙(3.3~7.7eV)藉由調整鋅與鎂的比例，進而能達到深紫外光波段，此外材料系統具有獨特性質，例如:本質遮蔽可見光，相對低溫薄膜合成與可用的晶格匹配基板，因此其薄膜結構在紫外光發光與偵測元件的應用受到很大的重視。根據實驗結果顯示，發現以Mg0.3Zn0.7O為靶材並且改變基板溫度(25~250℃)所沉積的薄膜能有效調變鎂含量，沉積於矽基板薄膜中鎂的含量變化為40.7~51at.%，當基板溫度為200℃(Mg 47.6at.%)薄膜生成第二相立方晶體結構，進而影響薄膜壓電與光電性質。根據顯微結構分析，發現本實驗藉由鍍膜參數的調控，成功合成出具有奈米柱狀晶的氧化鎂鋅薄膜，該結構具有顯著的氧氣吸脫附機制，進而有利於延長載子壽命提升原件的光電性質。本實驗亦沉積氧化鎂鋅薄膜於聚醯亞胺基板，為耐熱性高分子材料同時具備優良的光學及電氣絕緣特性以及機械性質等優點，未來光電產業發展穿戴式與可饒式元件，以該基板為基底之元件將會很有競爭力，氧化鎂鋅薄膜鎂含量變化量小(38.5~44at.%)沒有相轉化發生，並且結晶態保持Wurtzite結構，具有C軸的高度不對稱性將有利於產生壓電特性能調控元件之光電傳輸特性，進而結合於近年來發展出之壓電電子（Piezotronic）和壓電光電子（Piezo-phototronic）效應來提升元件之性質表現。
本實驗將氧化鎂鋅薄膜製備成蕭特基接觸指叉式紫外光偵測器，實驗結果顯示，當基板溫度為150℃沉積於矽基板的氧化鎂鋅薄膜(Mg 43.7at.%)具有最優異光電特性，同時具有最佳壓電係數，因此選用此參數薄膜施予壓電光電子效應與光響應之量測，並且與基板溫度同為150℃沉積於聚醯亞胺基板的氧化鎂鋅薄膜(Mg 42.8at.%)進行性質比較。由光響應量測結果顯示，矽基板/聚醯亞胺基板元件在波長291nm/295nm處具有最大響應值，並且具有優異鑑別率(Rejection ratio)與靈敏度(Sensitivity)，結果證實原件具有偵測深紫外光UV-B之能力。

We demonstrate the growth of high quality, single phase, wurtzite MgZnO nanorod array thin films on p-type Si (111) and polyimide substrates by magnetron sputtering using Mg0.3Zn0.7O as a target. The films are composed of nanorod arrays highly oriented along the c-axis without any buffer layer. The Mg content of the MgZnO alloys on Si/PI substrate can be varied in a large range 40.7-51 at.%/38.5-44 at.% by changing the substrate temperature from 25 to 250 ºC. The heterostructures of MgZnO/Si and MgZnO/PI, deposited at 150 ºC were fabricated into metal-semiconductor-metal photodetectors. The sensitivity of the Si/PI based device is as high as 4.3×104 %/1×103 % at 2 V bias under 325 nm laser at a relatively low illumination intensity (2.77 mW) and the output photocurrent increased with an increase in the UV illumination intensity at both -10 and +10 V biased voltage. The responsivity of the Si/PI based device 4.6 A/W/0.3mA/W is achieved at 292/295 nm with a cutoff wavelength of 305/310 nm and a bias voltage of 9 V. The UV responsivity of Si/PI based photodetectors were enhanced by tuning the SBH 2.6meV/13meV when a compressive strain was applied on the device under piezo-phototronic effect.

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