Very High Mobility HgTe Films Grown on GaAs Substrates by Molecular Beam Epitaxy.

Superlattice structures incorporating HgTe wells and either ZnTe or CdTe barriers are promising candidates for novel optoelectronic devices. In this this work, both (100)- and (111)-oriented HgTe films have been grown on GaAs. In agreement with what has been reported for growth on II-VI substrates, we find higher Hall mobilities in (100) films. An 80K mobility of 92,200 cm sup 2 V sup (-1) s sup (-1) has been achieved. This mobility is higher than has previously been reported for growth on (100) II-VI substrates, and is twice the best value previously reported for growth on GaAs. This result indicates that GaAs can be used as a substrate for the growth of the highest quality HgTe.