GaAs-on-silicon conformal vapor-phase epitaxy using reversible transport and selective etching reactions with water vapour

Selective and conformal heteroepitaxy of GaAs on silicon using a close-spac ed vapor transport (CSVT) process based on a reversible water-vapor transpo rt reaction is described here. In selective epitaxy, a GaAs him is grown pr eferentially through openings defined in an oxide mask which coats a silico n wafer. For conformal epitaxy, a simple CSVT process has been demonstrated for epitaxial lateral overgrowth of submicron-thick GaAs films in cavities formed on (1 1 1) silicon substrates. Details of a conformal GaAs-on-silic on CSVT technique and experimental results showing its feasibility are pres ented. (C) 2001 Elsevier Science B.V. All rights reserved.