Abstract
In the very long wavelength infrared (VLWIR) band, λ>14 microns, the detector materials are currently limited to extrinsic semiconductors. These extrinsic materials can be either heavily doped bulk semiconductor, like silicon or germanium, or a doped quantum well heterostructure. An alternative choice that provides the opportunity for higher temperature operation for VLWIR sensing is an intrinsic material based on a type-II InAs/Ga(In)Sb superlattice. There are many possible designs for these superlattices which will produce the same narrow band gap by adjusting individual layer thicknesses, indium content or substrate orientation. The infrared properties of various compositions and designs of these type-II superlattices have been studied. In the past few years, excellent results have been obtained on photoconductive and photodiode samples designed for infrared detection beyond 15 microns. An overview of the status of this material system will be presented. In addition, the latest experimental results for superlattice photodiodes with cut-off wavelengths as long as 30 microns will be covered.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 191-198 |
| Number of pages | 8 |
| Journal | Proceedings of SPIE - The International Society for Optical Engineering |
| Volume | 5074 |
| DOIs | |
| State | Published - 2003 |
| Event | Infrared Technology and Applications XXIX - Orlando, FL, United States Duration: Apr 21 2003 → Apr 25 2003 |
Funding
This work is supported by the United States Air Force Office of Scientific Research (USAFOSR) lab task 08RY08COR. The authors would also like to acknowledge support from the National Science Foundation (NSF) and the State of Arizona Technology & Research Initiative Funding Photonics Foundation.
Keywords
- Detector
- Infrared
- Photodiodes
- Superlattice
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Computer Science Applications
- Applied Mathematics
- Electrical and Electronic Engineering