Growth of high-quality GaN on Si(111) substrate by ultrahigh vacuum chemical vapor deposition

An ultrahigh vacuum chemical vapor deposition (UHVCVD) system was employed to grow high-quality GaN on a Si (111) substrate using a thin AlN buffer la yer. X-ray diffraction, high-resolution electron microscopy (HREM), and pho toluminescence (PL) data indicate that a single crystalline GaN layer with a wurtzite structure was epitaxially grown on a silicon substrate. The full width at half maximum (FWHM) of the x-ray rocking curve for the GaN (0002) diffraction was 16.7 arc min. A cross-sectional HREM image showed an amorp hous SiNx layer at the Si/AlN interface, as well as stacking faults and inv ersion domain boundaries in the GaN epilayer. An intense PL emission line, which is associated with the recombination of the donor bound exciton, was observed at 10 K PL spectra (FWHM = 6.8 meV) and a strong band edge emissio n was obtained (FWHM=33 meV) as well, even at room temperature. These resul ts indicate that high-quality GaN can be grown on Si (111) substrates using a UHVCVD growth method. (C) 2001 American Institute of Physics.