Compositional non-uniformities in selective area growth of GaInAs on InP grown by OMVPE

Abstract

Selective area epitaxial growth of Ga0.47In0.53As on InP substrates patterned with silicon nitride was done by low pressure organometallic vapor phase epitaxy. Good surface morphology and clean side walls of the epitaxial layers were obtained in most of the areas of selective GalnAs growth. However, both GaAs incorporation and InAs incorporation increased near the edges of the selective growth areas due to the extra flux of Gacontaining and In-containing species migrating on the surface of silicon nitride. The increase in InAs incorporation was found at a higher rate when the adjacent silicon nitride area was large, hence, cross-hatching appeared near the edges. A characteristic length of adjacent silicon nitride seemed to be connected with the enhanced InAs incorporation, which was about 40μm at 600°. The non-uniformities in composition appeared in all wafers grown in the temperature range between 570 and 650°.