Films of GaAs were grown, using molecular beam epitaxy, onto vicinal (100)Si substrates and were examined by means of transmission electron microscopy. It was found that the threading dislocation density varied slightly at mid-range angles (1.5º to 6º) and was of the order of 108/cm2. The dislocation density was significantly reduced at tilt angles below 1º. However, a large number of planar defects appeared at very small or large angles. The appearance of micro-twins in a narrow zone was characteristic of an 0.5º tilt angle, while the anisotropic growth of stacking faults characterized films which were grown onto substrates with a large tilt angle.

Interplay between planar defects and threading dislocations in GaAs-on-Si A.Delimitis, C.B.Lioutas, K.Michelakis, A.Georgakilas: Materials Science Forum, 1999, 294-296, 317-20