Growth of strained Ga1-xInxP layers on GaP (001) by gas source molecular beam epitaxy: similarities and differences with the growth of strained arsenides

Using reflection high energy electron diffraction and atomic force microsco py, the growth of Ga1-xInxP alloys on GaP (0 0 1) with x varying from 0.2 t o 1 (InP) is investigated and compared to that of arsenides on GaAs (0 0 1) or InP (0 0 1). Ar 520 degreesC, the evolution of the critical thickness f or 3D growth versus In content is rather similar to that observed in the Gs InAs/GaAs system. For x less than or equal to 0.5, 3D growth leads to the d evelopment of wire-like structures along the [1 1 0] direction which can he related to recent results on the phophide surface reconstructions. Finally , for the growth of InP on GnP at 520 degreesC, the critical thickness is 2 .1 MLs and we observe a small density of very large islands, in contrast to the InAs/GaAs case. At 400 degreesC, the critical thickness decreases (1.7 MLs) as well as the island mean size whereas the density increases, We dis cuss this behavior in terms of surface energy. (C) 2001 Elsevier Science B. V. All rights reserved.