Crystal growth of high quality hybrid GaAs heteroepitaxial layers on Si substrate by metalorganic chemical vapor deposition and liquid phase epitaxy

This paper reports the first successful liquid-phase epitaxial (LPE) growth of hybrid GaAs from a Bi solvent for the starting growth temperature (SGT) of 650 degrees C on GaAs coated Si grown by metalorganic chemical vapor deposition (MOCVD) without oxide strip windows, The hybrid-grown GaAs on Si has shown better crystallinity than the MOCVD-grown one. The quality of the grown layers has been characterized by photoluminescence (PL), double-crystal X-ray diffraction (XRD) and etch pit density (EPD). The PL intensity increased nearly twice and the full-width at half-maximum (FWHM) of the double-crystal XRD is reduced to 125 arcsec after the growth of GaAs layers by LPE. The dislocation density was about 7 times lower than the dislocation density observed in the MOCVD GaAs on Si layer which served as a substrate for the LPE growth. The cross-sectional view was observed by scanning electron microscope (SEM) and transmission electron micrograph (TEM). The TEM results indicate that the high dislocation density has drastically reduced in the LPE layer. (C) 1998 Elsevier Science B.V. All rights reserved.