ABSTRACT
Many types of optoelectronic devices can be enhanced significantly through the introduction of quantum confinement in reduced dimensionality heterostructures. This was the main motivation for the study of superlattices (SLs) as an alternative to infrared (IR) detector materials. The HgTe/CdTe SL system was proposed in 1979, only a few years after the first GaAs/AlGaAs quantum heterostructures were fabricated with molecular-beam epitaxy (MBE). It was anticipated that SL IR materials would have several advantages over bulk HgCdTe (the current industry standard) for this application:
a higher degree of uniformity, which is importance for detector arrays;
smaller leakage current due to the suppression of tunneling (larger effective masses) available in SLs; and
lower Auger recombination rates due to substantial splitting of the light- and heavy-hole bands and increased electron effective masses.
