The effect of high temperature-high hydrostatic pressure treatment (HT–HP) on photoluminescence of heavily doped GaAs : Be layers grown by MBE on the GaAs substrate was investigated. A blue shift of the near-band-gap luminescence line and a rise of an additional high energy shoulder are observed after HT–HP treatment in the spectra of the layers with Be atoms concentration more than 5 · 1019 cm-3. These layers also demonstrated a concentration related decrease of the lattice parameter (as studied by X-ray methods) not fulfilling the Vegard law. These effects can be explained by creation of Be inclusions in GaAs. Due to different compressibility and thermal expansion of the Be inclusions and the layer material, the HT–HP treatment results in the creation of some structural defects, which lead to an increased probability of non-k-conserving transitions.
Физика и техника полупроводников, 2004, том 38, вып.