The structural state of epitaxial GaP films of different polarities grown on misoriented Si(001) substrates

The structure of GaP films grown by molecular-beam epitaxy on vicinal Si(1113) substrates has been studied by X-ray diffraction. It is established that the crystalline lattice of a pseudomorphic film rotates about the axis toward increasing deviation from the singular orientation, while the subsequent relaxation leads to rotation in the opposite direction. This is valid for the films of both (001) and (001̄) polarities. Differences between the surface morphologies of relaxed and pseudomorphic GaP films are revealed.