MBE Growth of Hg-Based Materials for Near Infrared Applications

HgCdTe has been the material of choice for detectors in the atmospheric transmission windows at 5 and 10 microns. This material system offers advantages that may prove useful for shorter wavelength applications. Among these are a large variation in bandgap in a lattice matched system, which allows bandgap engineering techniques to be used; and resonance between the spin orbit splitting and the bandgap at 1.5 micron, for low noise avalanche photodetectors. We have found that the methods for MBE growth of long wavelength HgCdTe can readily be extended to near infrared compositions. Hall and photoluminescence measurements show that these films are comparable to high quality bulk crystals. We also will discuss results for ion implantation and rapid thermal annealing for both p- and n-type doping.