Growth of high quality GaAs layers on Si substrates by MOCVD

Abstract

High quality GaAs layers were grown on Si(100) wafers by heat treatment of the substrates at high temperatures and a subsequent two-step growth sequence at low temperature and then at the conventional growth temperature. The grown layers showed a high quality, i.e., a single domain structure, a mirror-like surface, high electron mobility, fairly high photoluminescence intensity and low etch pit density. Cross-sectional TEM observation showed that most of the misfit dislocations were confined in the narrow region near the GaAs/Si interface. The growth of GaAs on Si substrates with spherical surfaces showed that a small offset angle from (100) was necessary to grow a single domain GaAs layer. FETs and LEDs fabricated on the grown layers showed nearly the same characteristics as those of the devices on GaAs wafers.