Growth and characterization of GaN films on Si(111) substrate using high-temperature AlN buffer layer

Hexagonal GaN films exceeding 1 μm have been prepared on Si(111) substrates using high-temperature AlN buffer layers, and no cracks were observed. The FWHM of X-ray rocking curve for GaN (0002) was 560 arcsec. Strong band-edge photoluminescence (PL) was present in PL spectra. Micro-Raman spectra using shifts of E2 phonon showed that GaN films were in compressive stress, which agreed with the characterization result of X-ray lattice parameters method.