MERCURY CADMIUM TELLURIDE AS AN INFRARED DETECTOR MATERIAL

The properties of the alloy semiconductor Hgi_.CdxTe and its application as an infrared detector material are reviewed. The selection of this alloy system as an infrared detector material is discussed. Bulk and epitaxial crystal growth techniques are described and representative electrical data presented which show the free carrier concentration to be in the 1014.-1015 cm-2 range. The flexibility of this ternary system is then discussed relative to the compositional dependence of the energy gap. Photoconductive response data are presented for detectors having response peaks of 4–20 microns over the temperature range 15°-300IC. The expression Eg = 1.6(x - 0.134) + 0.1335(0.435 - x) (T/100 - 1) 40° < T < 240°K 0.15 < x < 0.35 is shown to represent the compositional and temperature dependence of the energy gap within the specified limits. © 1969 IEEE. All rights reserved.