The effect of edge thinning structure on the performance of InAs/GaAs Quantum dot infrared photodetectors

• Main Authors: Zong-Ming Wu, 吳宗銘
• Other Authors: 李嗣涔
• Format: Others
• Language: en_US
• Published: 2013
• Online Access: http://ndltd.ncl.edu.tw/handle/11210798860423931605

碩士 === 國立臺灣大學 === 電子工程學研究所 === 101 === Recently, the methods of promoting the operation temperature have attracted much attention. Experimental evidences have demonstrated that QDIPs exhibit improved properties by lowering the dark current. However, the main factors that determine the dark current are still unclear; leading to the effect is limited. It was proven that raising the photocurrent can enhance the responsivity and hence the operation temperature is elevated. First, exploring the dark current mainly dominated by bulks or surfaces of the devices was studied. Second, the improvement of InAs/GaAs QDIPs using the new structure, well-in-dot structure, was investigated. The InGaAs quantum well layer can provide free carriers to fill InAs QDs and enhances the responsivity. By analyzing experimental results and theoretical model, carrier dynamics have been established to explain the operation principle of WD-QDIPs. Third, another way to enhance the characteristics of QDIPs is edge thinning structure, resulting in the reduction of the dark current. High operation temperature can be achieved with large edge thinning width.