CdTe/MgTe heterostructures: Growth by atomic layer epitaxy and determination of MgTe parameters
Résumé
Atomic layer epitaxy (ALE) is investigated for the binary semiconductor MgTe. Reflection high-energy electron-diffraction studies on MgTe atomic deposition, together with x-ray diffraction, high-resolution transmission electron microscopy, and photoluminescence experiments on ALE-grown CdTe/MgTe superlattices are reported. They reveal that an autoregulated growth at 0.7±0.1 MgTe monolayer/ALE cycle can be achieved in a substrate temperature range between 260 and 300°C. New values of the zinc-blende MgTe lattice parameter, aMgTe=6.420 ±0.005 Å, of the ratio of the elastic coefficients 2c12c11 (MgTe)=1.06, and of the 300 K MgTe band gap, EG=3.5 eV, are obtained by correlating x-ray-diffraction and optical results.