Share Email Print

Proceedings Paper

Investigation of charge-trapping effects in InSb focal plane arrays
Format Member Price Non-Member Price
PDF $14.40 $18.00

Paper Abstract

We are investigating trapping/recombination centers in near-infrared (1 - 5 micrometers ) InSb imaging arrays via experimentation and theoretical modeling. The presence of impurities, lattice defects and/or surface states can compromise the operational qualities of an imaging array by introducing latent images, signal rate/quantum efficiency loss at low signal levels, and by increasing noise and dark current. Identification of these trapping centers should enable a reduction in their number density by appropriate changes in the material processing and fabrication steps. We have performed experiments and analyses on both gate-controlled arrays (SiOx surface passivation) and recently received gateless arrays (Si3N4 surface passivation). All of the gated arrays showed latent images at temperatures 6 - 26 K for signal fluxes as low as 1500 e-/s/pixel, while neither of the two gateless arrays examined has shown latent images in the same temperature range; no latent image was detected (to a level of < 50 e-) in a 5 second integration after exposure to a 2 X 106 e-/sec/pixel signal flux. We interpret this as evidence for surface state charge trapping in the region of the gate oxide, which is largely eliminated by the new passivation. The physics of surface states is investigated theoretically in order to gain an understanding of the surface contribution to the observed behavior, and a model is presented to explain the experimental results.

Paper Details

Date Published: 20 October 1993
PDF: 13 pages
Proc. SPIE 1946, Infrared Detectors and Instrumentation, (20 October 1993); doi: 10.1117/12.158702
Show Author Affiliations
Steven Lawrence Solomon, Univ. of Rochester (United States)
James D. Garnett, Univ. of Rochester (United States)
Hao Chen, Univ. of Rochester (United States)

Published in SPIE Proceedings Vol. 1946:
Infrared Detectors and Instrumentation
Albert M. Fowler, Editor(s)

© SPIE. Terms of Use
Back to Top