High performance HgCdTe two-color infrared detectors grown by molecular beam epitaxy

High-performance in situ doped two-color detectors with the n-p-n architecture for the sequential detection of mid: and long-wave infrared radiation were grown by molecular beam epitaxy. These detector structures were twin-free, and exhibited narrow rocking curves ( 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 properties measured. The spectral response of the mid-wave and long-wave diodes in the integrated detector were characterized by sharp turn-on and turn-off in both bands. Average R o A values of 100 Ω cm 2 at 10.5 μm and 5.5 x 10 5 Ω cm 2 at 5.5 μm were measured at 77 K. These results are comparable to those of the best unispectral detectors and represents a significant milestone for MBE-grown HgCdTe two-color devices