本研究以1:1到3:1KSCN與CuSO4比例製備電鍍液應用於光感測器上，利用CuSCN 與ZnO之間PN.接面的特性達元件效率優化。由於利用蕭特基接觸製作的氧化鋅光感測器，需要外加電場才會有效率並且高電場造成的周圍擾動，致使上升時間與下降時間過長；此外，CuSCN作為光感測器P型材料研究較少，穩定性佳，且其能隙位於3.6-3.9eV能使紫外光有效吸收於氧化鋅。本研究以霍爾量測、XRD、SEM及UPS來探討其材料機制，採取以不同比例KSCN與CuSO4製備， 發現晶相漸漸由I(003)轉向I(101)並由β-CuSCN轉為α-CuSCN。且在霍爾量測中發現在比例2:1的情況下，載子移動率最高。對於電子電洞分離速度有很顯著的效果，大大的提升了氧化鋅光感測器的反應速度。最後利用UPS與UV-Vis測量其能帶圖，可以發現電鍍液比例改變能夠將HOMO值由原本的5.1調整至接近ITO能階的4.77。
而在電鍍厚度部分，發現隨著厚度增加，晶相由I(003)轉向I(101)，其粗糙度也隨著I(101)晶相的增加而上升。經過霍爾量測我們可以發現隨著厚度的增加，其載子濃度也會提升，在載子移動率部分，當CuSCN膜的厚度達800nm時最高。而由UPS與UV-Vis的量測，可以發現其HOMO值會先下降，直至800nm達到最低的4.77。再增加厚度，HOMO值慢慢提升至5.35。會有這種現象主要是因為銅空缺多寡，由XPS量測可以發現當厚度在800nm時，Cu與SCN比例為0.677，相較200nm時Cu:SCN比例0.9，銅空缺量明顯變多了。然而當厚度到達1400nm時，Cu:SCN比例0.769銅空缺量減少，HOMO值也隨之上升。
於元件端本研究目的是藉由電鍍不同比例電鍍液CuSCN來提升元件效率，而最終元件上升時間與下降時間可從12s/18s優化至6s/12s，有效地降低了6秒的反應時間，在響應度部分，可由原本6mA/W提升至27.3mA/W了4.55倍。代表本實驗改變電鍍液比例能夠明顯提升元件表現，其原因是由於在電鍍液比例2:1時，其載子飄移率最高，有效的降低了響應時間，並且其Cu離子會參與水熱法反應，使氧化鋅形貌從原本的奈米柱變成奈米花，大幅的增加吸光面積，並在HOMO部分也由原本的5.1eV下降至4.77eV大大的降低了其與ITO之間的能障，達元件最佳化結果。

In this study, we use different electrolyte ratio and charge density to optimize the thin film of CuSCN. When we change electrolyte ratio, we found that the polymorphic form of the CuSCN change from β-CuSCN to α-CuSCN when we increase the ratio of SCN in the electrolyte.And we get the highest mobility and lowest carrier concentration when the electrolyte Cu: SCN 1:2. We also found that because of the Cu vacancy, valance band of the CuSCN which the electrolyte Cu: SCN=1:2 is 4.77eV near ITO. The energy barrier between ITO and CuSCN decrease, it is helpful for the application for the ITO/CSCN base device. Then, we discuss the influence of the charge density to CuSCN thin film characteristic. We observe that the carrier concentration become higher when we increase the charge density. And we also get the highest mobility when the charge concentration set to 120mC/cm2.Finally, we combine the result above and produce a self-powered photodetector. In this research, we found that when the electrolyte ratio Cu: SCN= 1:2, the responsivity of the device is the highest.It is becauce of the nano structure of ZnO turn from nanorod to nanoflower. We also observe that the fastest response time of the photodetector appears when electrolyte ratio Cu:SCN=1:2.

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