Journal of Electronic Materials

, Volume 33, Issue 6, pp 517–525

Spectral crosstalk by radiative recombination in sequential-mode, dual mid-wavelength infrared band HgCdTe detectors

  • R. A. Coussa
  • A. M. Gallagher
  • K. Kosai
  • L. T. Pham
  • G. K. Pierce
  • E. P. Smith
  • G. M. Venzor
  • T. J. De Lyon
  • J. E. Jensen
  • B. Z. Nosho
  • J. A. Roth
  • J. R. Waterman
Special Issue Paper

DOI: 10.1007/s11664-004-0040-y

Cite this article as:
Coussa, R.A., Gallagher, A.M., Kosai, K. et al. Journal of Elec Materi (2004) 33: 517. doi:10.1007/s11664-004-0040-y

Abstract

For small pixel, infrared (IR) focal plane arrays (FPAs), Raytheon Vision Systems’ architecture for integrated, dual-band detectors uses the sequential mode of the n-p+-n configuration. There is a single indium bump per pixel, leaving the p+ layer floating, and the operating polarity of the bias selects the spectral sensitivity by reverse-biasing the active p-n junction. Photogenerated minority carriers in the absorber layer of the forward-biased inactive photodiode are lost through recombination. This paper is the first report of a new optical crosstalk mechanism that occurs in sequential-mode, dual-band detectors. In the long-wavelength mode under out-of-band, short-wavelength illumination, radiative recombination yields emission near the bandgap energy of the short-wavelength absorber layer, resulting in a spurious short-wavelength response that appears as spectral crosstalk. We present experimental and device modeling results on the spectral crosstalk in molecular-beam-epitaxy-grown HgCdTe arrays with the cutoff wavelength of both bands in the 4–5-µm range.

Key words

HgCdTeinfrared detectortwo-color detectorcrosstalkradiative recombination

Copyright information

© TMS-The Minerals, Metals and Materials Society 2004

Authors and Affiliations

  • R. A. Coussa
    • 1
  • A. M. Gallagher
    • 1
  • K. Kosai
    • 1
  • L. T. Pham
    • 1
  • G. K. Pierce
    • 1
  • E. P. Smith
    • 1
  • G. M. Venzor
    • 1
  • T. J. De Lyon
    • 2
  • J. E. Jensen
    • 2
  • B. Z. Nosho
    • 2
  • J. A. Roth
    • 2
  • J. R. Waterman
    • 3
  1. 1.Raytheon Vision SystemsGoleta
  2. 2.HRL Laboratories LLCMalibu
  3. 3.Naval Research LaboratoryWashington, DC