本實驗首先利用熱氧化法400˚C製備出氧化銅奈米線，接著以熱蒸鍍法將氧化鋅沉積到氧化銅奈米線上，形成異質結構，經過不同的退火時間，探討其光伏特性的應用。在FESEM的結果顯示出，氧化鋅將氧化銅奈米線包覆的非常均勻且完整，且隨著退火時間的增加，表面形貌並沒有顯著的變化，從XRD的結果顯示出，尚未退火仍有鋅繞射峰值存在，隨著退火時間的增加，氧化鋅的結晶性越好。從I-V特性曲線量測結果得知，經過退火後的ZnO/CuO奈米線，都有好的整流特性，且能量轉換效率隨著退火時間的增加而得到改善。在光響應表現方面，退火10分鐘的300 nm光響應為4.11×10-2 (A/W)最高，當退火時間增加至30分鐘，缺陷變多造成其光響應為2.15×10-3 (A/W)最差，另一方面，在300 nm紫外光照射下，其光電流變化在未退火的條件下，其光電流的上升及下降時間都是最長的，且電流在衰退的時候，並不會回到原本的暗電流值，其原因為尚未退火時，內部缺陷過多，導致上升及下降時間變慢，缺陷去捕捉光產生的電子，使得電流無法回到原本的暗電流值經過退火10分鐘後，材料結晶性變好、缺陷變少，使得有較快的上升及下降時間。

CuO nanowires has been successfully prepared by thermal oxidation of copper films at 400˚C. ZnO is deposited on CuO nanowires to format ZnO/CuO heterostructure by thermal evaporation. FESEM results show that ZnO covers CuO nanowires uniformly and its morphology remains unchaned after annealing. As-deposited sample shows Zn diffraction peaks, indicates the presence of Zn. Annealing results in oxidation of residual Zn. I-V measurement shows that ZnO/CuO nanowires exhibit good rectifying behavior after annealing and its power conversion efficiency improves as well. Photoresponse measurement shows that 10 minutes annealed sample shows a maximum responsivity of 4.11×10-2 (A/W) at 300nm. Increasing annealing time results in reduced responsivity to 2.15×10-3 (A/W) due to the increase of oxygen vacancy defects. The rise time and decay time of photoresponse was found to be dependent on annealing condition as well, which is due to the competition of recrystalization and decomposition of ZnO.

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