Analysis of Dark Current Mechanisms for Split-Off Band Infrared Detectors at High Temperatures

作者：Lao Y F^*; Jayaweera P V V; Matsik Steven G; Perera A G Unil; Liu H C; Buchanan M; Wasilewski Z R

来源：IEEE Transactions on Electron Devices, 2010, 57(6): 1230-1236.

DOI：10.1109/TED.2010.2046065

• Dark currents
• GaAs-AlGaAs
• heterojunctions
• infrared detectors

An analysis of dark current mechanisms has been performed on high-operating-temperature (up to 330 K) split-off (SO) band p(+)-GaAs/AlGaAs heterojunction infrared detectors (3-5 mu m). In contrast to conventional 1-D current models due to carrier transport based on tunneling and/or thermionic emission mechanisms, a 2-D electrical model is used to explain nonuniformity degradation of zero-bias differential resistance (R(0)A) with temperatures as measured on SO detectors. The 2-D characteristic of carrier transport could have the limitation on high-temperature performances of detectors and, hence, needs optimizing. A theoretical model shows that this 2-D effect can be reduced by structural modifications such as using smaller mesa sizes, higher doping of the p(+)-GaAs layer, and a higher potential barrier that prospectively provides better electrical uniformity for SO detectors working at high temperatures.

• 出版日期2010-6