THE FACET EVOLUTION DURING METALORGANIC VAPOR-PHASE EPITAXIAL-GROWTH ON V-GROOVED HIGH MILLER INDEX GAAS SUBSTRATES

Abstract

The facet evoluting during metalorganic vapor phase epitaxial (MOVPE) growth on high Miller index V-grooved GaAs substrates with (1311)A, (511)A, (311)A, and (211)A as well as (100) orientations, has been investigated. The {433}A and (100) facets evolved on the as-etched V-grooved substrate having {111}A side walls, regardless of substrate orientation. As the substrate orientation is tilted toward (211)A, the (433)A facet on the long-side wall is extended, while the length of the newly formed (100) facet on the other side is reduced. The (433BAR)A facet on the short-side wall formed in the early stage of growth diminishes more rapidly. The direction of the locus line of the intersection points between the two facets is initially [100]. However, this direction eventually changes after the (433BAR)A facet on the short-side wall disappears. The growth rate properties of the facets can be explained by channel effect and different surface mobilities of different species.