Correlation between the surface morphology and antiphase boundaries in ordered (GaIn)P

The surface of metal-organic vapor-phase epitaxy (MOVPE) grown CuPtB-type o rdered (GaIn)P epitaxial layers and their interface to the GaAs substrate h ave been investigated using high-resolution transmission electron microscop y (HRTEM). We find the (GaIn)P surface to consist of bunched supersteps, (0 01) terraces, and vicinal regions. The dependence of the height and the den sity of supersteps, the portion of monolayer steps contained in supersteps as well as the density of antiphase boundaries on the growth temperature an d the substrate misorientation is investigated. By comparing the densities of the supersteps and the antiphase boundaries on the (GaIn)P surface and a t the interface to GaAs, we find that the supersteps at the interface are t he preferential formation site of antiphase boundaries in (GaIn)P. The corr elation is disturbed, however, by the effect of the width of supersteps and (001) terraces and of the existence of vicinal regions on the APE formatio n. (C) 1999 Elsevier Science S.A. All rights reserved.