Surface characterization of epitaxial lateral overgrowth of InP on InP/GaAs substrate by MOCVD

Epitaxial lateral overgrowth (ELO) of InP on InP/GaAs substrates by low-pressure metalorganic chemical vapor deposition (LP-MOCVD) was investigated. The lateral overgrowth InP layers were obtained on the SiO2 masked InP seed layer, which was deposited on the (1 0 0) GaAs substrate by the two-step method. The surface characterization of overgrowth InP was dependent on the V/III ratio, the mask width and the growth time. When decreasing the V/III ratio or reducing the mask width respectively, the sidewalls “competition effect” was obviously observed. After a longer time, new (1 0 0)-like top surfaces were formatted because of the precursors migrating from the sidewall facets to the (1 0 0) top surfaces. The experimental findings will be explained by growth kinetics in conjunction with the different dominant source supply mechanism.