Molecular beam epitaxial growth of a novel strained layer type III superlattice system: HgTe-ZnTe

HgTe-ZnTe strained type III superlattices have been grown for the first time using the molecular beam epitaxy technique. Three superlattices grown at 185 °C have been characterized by electron and x-ray diffraction, infrared absorption, and Hall measurements. The presence of satellite peaks in the x-ray spectra shows that the superlattices are of good quality despite the large lattice mismatch between HgTe and ZnTe (Δa/a=6.5%). These superlattices are p type and the hole mobilities are very high compared to those of the corresponding alloy. Such a phenomenon has already been reported for HgTe-CdTe superlattices. Infrared transmission spectra show that HgTe-ZnTe superlattices have narrower band gaps than equivalent HgZnTe alloys.