GaAs/AlGaAs multiquantum-well IR detectors

GaAs/Al(0.31)Ga(0.69)As IR detector of multiquantum well structure with a single bound state in a GaAs well have been fabricated. The peak wavelength of spectral responsivity at 77 K was 8.3 microns. The measured responsivities were 20 V/W for A-type detectors, 65 V/W for B-type detectors, and 130 V/W for C-type detectors. The corresponding specific detectivities at peak wavelength were 2.8 x 10 exp 9 cm sq rt Hz/W, 2.7 x 10 exp 9 cm sq rt Hz/W, and 2.7 x 10 exp 9 cm sq rt Hz/W, respectively. These values are about one order lower than those of conventional CdHgTe photoconductive devices.