Effect of high temperature-pressure on GaAs layers grown on vicinal Si substrates

The effect of high hydrostatic pressure - high temperature treatment on str ain state of thin GaAs layers, grown on vicinal (001) Si substrate, misorie nted towards [110] with different miscut angles and with two different orie ntations of GaAs layer in relation to the miscut direction, was investigate d by X-ray diffraction methods. The strain of the GaAs layers and GaAs/Si s amples bending decreases when subjected to the treatment at T = 670 K under enhanced hydrostatic pressure (1.2 GPa). Dependence between the stress-ind uced structural changes and the orientation of GaAs miscut angle as well as peculiarities of the temperature-pressure treatment were determined. It ha s been shown that the amount of relaxed strain depends on the initial defec t structure of the GaAs/Si hetrostructure. After reannealing the samples at higher temperature (870 K - 1.2 GPa), the strain and sample bending were t he same as that after the treatment at 670 K - 1.2 GPa but the defect struc ture of layers was improved.