Growth of high quality GaAs layers on Si substrates by MOCVD

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.