Share Email Print

Proceedings Paper

Growth and performance of Ge:Sb blocked impurity band (BIB) detectors
Author(s): Jordana Bandaru; Jeffrey W. Beeman; Eugene E. Haller
Format Member Price Non-Member Price
PDF $17.00 $21.00

Paper Abstract

We report on growth, fabrication, and performance of Sb- doped Ge Blocked Impurity Band (BIB) detectors. Sb-doped Ge epilayers that exhibit impurity banding were grown on pure Ge wafers by Liquid Phase Epitaxy (LPE) from a Pb solution. A heavily doped surface region was observed using spreading resistance measurements. For proper BIB operation this layer must be removed by polishing. The diffusion of Sb into the blocking layer during growth has been studied as it affects the electric field distribution in a BIB detector. Secondary Ion Mass Spectroscopy analysis of an LPE layer grown at a starting temperature of 650 degrees C had a sharp interface. The growth of pure blocking layer material by LPE has been limited by the lack of availability of sufficiently pure commercial Pb, which we have found to contain phosphorus. Unintentionally doped layers grown from Pb solution were n- type approximately 1015 cm-3 with compensating acceptors approximately 1012 cm-3. This is too high for the blocking layer, but sufficient for the doped layer of an n-type BIB. We have studied Pb purification by distillation and evaporation and have reached a lower limit of 1014 cm-3. Ge:Sb BIB detectors have been fabricated by growing a doped IR active layer, typically 45 micrometers thick, and thinning the pure wafer to 10 micrometers to form the blocking layer. We demonstrate a working BIB device showing blocking behavior and a spectral response extending to 50 cm-1.

Paper Details

Date Published: 8 February 2002
PDF: 7 pages
Proc. SPIE 4486, Infrared Spaceborne Remote Sensing IX, (8 February 2002); doi: 10.1117/12.455106
Show Author Affiliations
Jordana Bandaru, Univ. of California/Berkeley and Lawrence Berkeley National Lab. (United States)
Jeffrey W. Beeman, Lawrence Berkeley National Lab. (United States)
Eugene E. Haller, Univ. of California/Berkeley and Lawrence Berkeley National Lab. (United States)

Published in SPIE Proceedings Vol. 4486:
Infrared Spaceborne Remote Sensing IX
Marija Strojnik; Bjorn F. Andresen, Editor(s)

© SPIE. Terms of Use
Back to Top