Abstract

Germanium infrared detectors are cut from a large zone leveled crystal. Compensation with antimony donors is used to obtain n-type material. The gold-antimony doped detectors have a long wavelength cutoff at 6 microns and a photoconductive time constant which is dependent on the wavelength of the incident radiation. A table is given which shows the sensitivity characteristics of a number of these detectors. Indium antimonide detectors have been made with sensitivities comparable to those of the gold-doped germanium. The indium antimonide detector is made either by alloying or diffusing a thin layer of impurities into the surface layer of a single crystal of material. Cadmium is presently being used, giving a thin p-type surface on n-type indium antimonide. If light is allowed to fall on the front surface of the alloyed material, a photovoltage may be measured between the n and p parts of the detector. The cutoff wavelength for this type of detector when cooled to liquid nitrogen temperature also is of the order of 6 microns.

A comparison is made between the characteristics of the two types of cells and a description is given of a multiple contact cell which can locate a target as well as detect it. A section is included on the standard measuring techniques used in evaluating infrared detectors.

© 1958 Optical Society of America

Cooled Photoconductive Infrared Detectors*

Werner Beyen, Peter Bratt, Howard Davis, Leo Johnson, Henry Levinstein, and Alfred MacRae
J. Opt. Soc. Am. 49(7) 686-692 (1959)

Extrinsic Detectors

Henry Levinstein
Appl. Opt. 4(6) 639-647 (1965)

Behavior of Lead Sulfide Photocells in the Ultraviolet*

Abbott Smith and David Dutton
J. Opt. Soc. Am. 48(12) 1007-1009 (1958)

Energy Transfers between Crystals and Adsorbed Dyes. II. Effect of Concentration on Efficiency of Sensitization*

R. C. Nelson
J. Opt. Soc. Am. 48(12) 948-952 (1958)

Antireflection Coatings for Germanium and Silicon in the Infrared*

J. T. Cox and G. Hass
J. Opt. Soc. Am. 48(10) 677-680 (1958)