Share Email Print

Proceedings Paper

Update on III-V antimonide-based superlattice FPA development and material characterization
Author(s): Lucy Zheng; Meimei Tidrow; Sumith Bandara; Leslie Aitcheson; Tiffany Shih
Format Member Price Non-Member Price
PDF $17.00 $21.00

Paper Abstract

Much progress has been made in the past 2 years in developing III-V antimonide-based superlattice infrared detectors and focal plane arrays (FPAs). In the area of detector material growth by molecular beam epitaxy, the wafer foundry group, helped by government-trusted entities and other partnering institutions, has leapfrogged many years of R&D effort to become the premier detector wafer supplier. The wafers produced are of high quality as measured by surface morphology, defect density, photoluminescence property, high-resolution X-ray diffraction, and diode current-voltage characteristics. In the area of detector design and FPA processing, the team-consisting of members from government laboratories, academia, and the FPA industry-has made rapid progress in device structure design, detector array etching, passivation, hybridization, and packaging. The progress is reflected in the steady reduction in FPA median darkcurrent density and improvement in median quantum efficiency, as well as reasonably low median noise-equivalent different temperature under 300 K scene background, when compared with the performance from some of the commercially available HgCdTe FPAs. In parallel with the FPA research and development effort, a small amount of funding has been devoted to measuring minority carrier lifetimes and to understanding life-killing defects and mechanisms of superlattice devices. Results of direct time-resolved photoluminescence measurement on superlattice absorbers indicate relatively short lifetimes (on the order of 30 ns) due to Shockley-Read-Hall mechanism. Modeling and curve fitting with diode current-voltage data indicate longer minority carrier lifetimes, although the best fit lifetime values differ greatly, possibly due to the difference in material quality and device structure. Several models or hypotheses have been proposed to explain experimental data. More data are required to validate these models and hypotheses. Further work is also necessary to reconcile the substantially different results from different groups and to truly understand the physics of minority carrier lifetimes, which is necessary to improve the lifetime and realize the theoretical promise of superlattice materials.

Paper Details

Date Published: 20 May 2011
PDF: 12 pages
Proc. SPIE 8012, Infrared Technology and Applications XXXVII, 80120S (20 May 2011); doi: 10.1117/12.888093
Show Author Affiliations
Lucy Zheng, Institute for Defense Analyses (United States)
Meimei Tidrow, U.S. Army Night Vision & Electronic Sensors Directorate (United States)
Sumith Bandara, U.S. Army Night Vision & Electronic Sensors Directorate (United States)
Leslie Aitcheson, U.S. Army Night Vision & Electronic Sensors Directorate (United States)
Tiffany Shih, U.S. Army Night Vision & Electronic Sensors Directorate (United States)

Published in SPIE Proceedings Vol. 8012:
Infrared Technology and Applications XXXVII
Bjørn F. Andresen; Gabor F. Fulop; Paul R. Norton, Editor(s)

© SPIE. Terms of Use
Back to Top
Sign in to read the full article
Create a free SPIE account to get access to
premium articles and original research
Forgot your username?