HIGH-PERFORMANCE HGCDTE 2-COLOR INFRARED DETECTORS GROWN BY MOLECULAR-BEAM EPITAXY

High-performance in situ doped two-color detectors with the n-p-n arch itecture for the sequential detection of mid- and long-wave infrared r adiation were grown by molecular beam epitaxy. These detector structur es were twin-free, and exhibited narrow rocking curves (approximate to 45 arcsec) as determined by X-ray measurements. The near surface etch pit densities in these device structures were typically (2-3) x 10(6) cm(-2). The structures were processed as mesas and their electrical p roperties measured. The spectral response of the mid-wave and long-wav e diodes in the integrated detector were characterized by sharp turn-o n and turn-off in both bands. Average R(0)A values of 100 Omega cm(2) at 10.5 mu m and 5.5 x 10(5) Omega cm(2) at 5.5 mu m were measured at 77 K. These results are comparable to those of the best unispectral de tectors and represents a significant milestone for MBE-grown HgCdTe tw o-color devices.