High performance InAs quantum dot infrared photodetectors (QDIP) on InP by MOCVD
Abstract
Inter-subband detectors such as quantum well infrared photodetectors (QWIP) have been widely used in infrared detection. Quantum dot infrared photodetectors (QDIPs) have been predicted to have better performance than QWIPs including higher operation temperature and normal incidence detection. Here we report our recent results of InAs QDIP grown on InP substrate by low-pressure metalorganic chemical vapor deposition (MOCVD). The device structures consist of multiple stacks of InAs quantum dots with InP barriers. High detectivities in the range of 1010cmHz1/2/W were obtained at 77K. The measurements at higher temperatures show better temperature dependent performance than QWIP. However, the performances of QDIPs are still far from the expected. One of the reasons is the low quantum efficiency due to the low fill factor of quantum dots layer. Resonant cavity enhanced QDIP has been studied to increase the quantum efficiency. Different schemes of mirrors using free carrier plasma and distributed Bragg reflector are discussed.
- Publication:
-
Quantum Sensing and Nanophotonic Devices II
- Pub Date:
- March 2005
- DOI:
- 10.1117/12.597139
- Bibcode:
- 2005SPIE.5732..326Z