ZnTe Superlattices Research Articles

Observations of structural deviations in MBE grown II–VI superlattices

X-ray diffraction analyses of HgTeCdTe and CdTeZnTe superlattices (SL's) have revealed a few exceptional samples possessing complex satellite structures that cannot be attributed to a single modulation period of one specific average composition. All of the examined SL's were grown, by molecular beam epitaxy (MBE), to have one well-defined period. Four of these unique SL's are reviewed and the observed deviations with respect to a single period SL model are illustrated. The SL samples are characterized by several diffraction techniques. Extended x-ray ω − 2θ scans were performed with the scattering vector along the SL growth direction. These scans were complemented by ω scans to assess the lateral coherence of the diffracting planes. The complex diffraction spectra suggest that several SL regions coexist within one macroscopic sample. Differences in the period and average composition distinguish each domain by observing the satellite spacing and central peak position, respectively.

A proposal for p-type ZnS1-xSex–ZnTe superlattices

Energy band structures ZnSe–ZnTe and ZnS0.5Se0.5 –ZnTe superlattices are calculated using the Kronig-Penney model taking into account strain effects due to the lattice mismatches between the materials. The ZnSe(30 Å)–ZnTe(5 Å) and the ZnS0.5Se0.5 (30 Å)–ZnTe(5 Å) superlattices have energy gaps of 2.5 and 2.7 eV, respectively. The ZnS0.5Se0.5 (30 Å)–p-type ZnTe(5 Å) superlattice is considered to be a p-type material of 1017 cm−3 and to be available for a hole injection layer to an n-type ZnSe layer.