The progress of a program to develop Ge:Ga blocked-impurity-band (BIB) detector arrays for far-infrared space astronomy is reviewed. So far, the best devices, working in the 80 - 200 micrometers range, have responsive quantum efficiency better than 15%, detective quantum efficiency 10%, dark current 100 electrons s^-1, and response uniformity better than a few percent. Structures with both bulk absorbers and epitaxial absorbing layers have been studied, as well as a variety of surface passivation. Front-illuminated arrays as large as 6 X 6, with 0.5 mm pixels, have been fabricated. Present performance conforms very well to the standard model of BIB detector operation. Further improvements in quantum efficiency and dark current, and larger formats, are anticipated, and the devices may play an important role in several upcoming far-infrared astronomical experiments.

Date Published: 15 July 1993
PDF: 10 pages
Proc. SPIE 1874, Infrared and Millimeter-Wave Engineering, (15 July 1993); doi: 10.1117/12.148068

Published in SPIE Proceedings Vol. 1874:
Infrared and Millimeter-Wave Engineering
Harold T. Buscher, Editor(s)