Effect of an applied electric current in epitaxial growth of GaAs layer on patterned GaAs substrate

Abstract

Selective epitaxial growth of a GaAs layer on SiNx masked Si-doped semi-insulating (100) GaAs substrate was performed by current-controlled liquid-phase epitaxy (CCLPE) in the conventional liquid-phase epitaxy. Experiments were carried out with and without the application of electric current. Surface morphology of (100) facet of the grown layer and the vertical and lateral growth rates were significantly improved under applied electric current. A thick layer of about 330μm was achieved at relatively low growth time of 6h with a current density of 20Acm−2. The epitaxial growth is realized by both electromigration of the solute and supercooling under a constant rate of furnace cooling. The dislocation density of the grown layer was significantly reduced, compared with that of the substrate (4×104cm2).