Anisotropic relaxation during the first stages of the growth of ZnTe/(001) CdTe strained layers studied by reflection high energy electron diffraction

The first stages of the growth of highly strained ZnTe on (001)CdTe are studied by reflection high energy electron diffraction (RHEED) with real‐time monitoring of the surface in‐plane lattice spacing and of the width of the streaks along the [100], [110], and [110] azimuths. A large, oscillating, elastic relaxation is measured below the critical thickness (≊5 ZnTe monolayers) in the [110] azimuth while a small excess of tensile stress with regard to the CdTe substrate is observed in the [110] azimuth. These effects are attributed to an anisotropic nontetragonal elastic distortion at the free edges of elongated 2D ZnTe‐monolayer islands. For large deposition times (i.e., after the critical thickness), the RHEED observation gives very good information about the nature of the dislocations occurring in the multiplication process.