HgCdTe MBE technology is becoming a mature growth technology for focal plane array applications. Device quality materials have been growth with alloy compositions required for SWIR to VLWIR applications. X-ray characterization results indicate that the epilayers exhibit FWHM of about 25 arc-sec, which is indicative of high quality materials. In addition to x-ray data, the observation of low defect density (EPD < 2 X 105/cm2), long minority carrier lifetime (t equals 1 micro-second for x equals 0.23, n equals 2 X 1015/cm3), and efficient IR photoluminescence, all attest to the device quality of HgCdTe epilayers grown by MBE. The breakthroughs to achieve In(n-type) and As(p-type) doping in-situ provide greater flexibility for fabricating advanced heterojunction devices. High-performance IR devices that use HgCdTe MBE materials are demonstrated. The additional development of drying etching and passivation in an ultrahigh vacuum environment coupled with an MBE growth system should lead to cost-effective and flexible manufacturing of devices for military and commercial applications.
Owen K. Wu,
"Status of HgCdTe MBE technology for IRFPA", Proc. SPIE 2021, Growth and Characterization of Materials for Infrared Detectors, (7 December 1993); doi: 10.1117/12.164952; https://doi.org/10.1117/12.164952