Molecular beam epitaxial growth and performance of HgCdTe-based simultaneous-mode two-color detectors

Molecular beam epitaxy was employed for the growth of HgCdTe-based n-p(+)-n device structures on (211)B oriented CdZnTe substrates. The device structures were processed as mesa isolated diodes, and operated as back-to-back diodes for the simultaneous detection of two closely spaced sub-bands in the mid-wave infrared spectrum. The devices were characterized by R,A values in excess of 5 x 10(5) Ohm cm(2) at 78K, at f/2 fov and quantum efficiencies greater than 70% in each band. Infrared imagery from a focal plane array with 128 x 128 pixels was acquired simultaneously from each band at temperatures between 77 to 180K, with no observable degradation in the image quality with increase in temperature.