Application of photoluminescence spectroscopy to studies of In$_{0.38}$Al$_{0.62}$As/In$_{0.38}$Ga$_{0.62}$As/In$_{0.38}$Al$_{0.62}$As metamorphic nanoheterostructures

The results of studies of the surface morphology, electrical parameters, and photoluminescence properties of In$_{0.38}$Al$_{0.62}$As/In$_{0.38}$Ga$_{0.62}$As/In$_{0.38}$Al$_{0.62}$As metamorphic nanoheterostructures on GaAs substrates are reported. Some micron-sized defects oriented along the [011] and $[0\bar{1}1]$ directions and corresponding to regions of outcropping of stacking faults are detected on the surface of some heterostructures. The Hall mobility and optical properties of the samples correlate with the surface defect density. In the photoluminescence spectra, four emission bands corresponding to the recombination of charge carriers in the InGaAs quantum well (1–1.2 eV), the InAlAs metamorphic buffer (1.8–1.9 eV), the GaAs/AlGaAs superlattice at the buffer-substrate interface, and the GaAs substrate are detected. On the basis of experimentally recorded spectra and self-consistent calculations of the band diagram of the structures, the compositions of the alloy constituents of the heterostructures are established and the technological variations in the compositions in the series of samples are determined.