Improving Ultraviolet Detection Performance of Nanostructured P-N Junction with Double Insulating Layers

• Main Authors: Jyun-Wei Chen, 陳俊瑋
• Other Authors: Feng-Renn Juang
• Format: Others
• Language: zh-TW
• Published: 2015
• Online Access: http://ndltd.ncl.edu.tw/handle/536hh7

碩士 === 國立中山大學 === 電機工程學系研究所 === 103 === In this thesis, the nanostructed P-N heterojunction with double insulating layers applied to ultraviolet (UV) detecting applications has been well studied. ZnO and CuO films were deposited on silicon substrate sequentially to form the heterojunction by using the RF sputtering system. ZnO film is also a seed layer for growing the nanorod structure by hydrothermal method. ZnO nanorods can improve the device performance to UV. HfO2 thin films were deposited on both sides of P-N heterojunction as insulating layers to enhance the sensitivity. Aluminum electrodes were deposited on the insulating layers to form the Al/HfO2/CuO/ZnO/HfO2/Al device structure. The morphology of the ZnO nanorods is related to the hydrothermal reaction time and the reagent concentrations. All these surface structures are observed by scanning electron microscope (SEM) to analyze the effects on device performance. The results show that the device under 0.1M hydrothermal solution for growing 5 hours has the best sensitivity to UV radiation after an annealing process. The sensitivity, rise time and recovery time are 158.7%, 3 s and 4 s, respectively. Nanorod structure can help UV has more chances be absorbed by the ZnO. Annealing process reduces the defects in the material. Double insulating layers restrain the dark current and enhance the sensitivity. The research has a great potential for applying into ultraviolet index (UVI) detection and aerospace industry.