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

Abstract

a b s t r a c tSelective epitaxial growth of a GaAs layer on SiN x masked Si-doped semi-insulating (1 0 0) GaAs substrate was performed by current-controlled liquid-phase epitaxy (CCLPE) in the conventional liquidphase epitaxy. Experiments were carried out with and without the application of electric current. Surface morphology of (1 0 0) facet of the grown layer and the vertical and lateral growth rates were significantly improved under applied electric current. A thick layer of about 330 mm was achieved at relatively low growth time of 6 h with a current density of 20 Acm À2 . 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 Â 10 4 cm 2 ).