High-quality semipolar GaN grown on carbon nanotube-patterned sapphire by hydride vapor phase epitaxy

Abstract

High-quality semipolar GaN is successfully grown on carbon nanotube-patterned sapphire (CNTPS) by hydride vapor phase epitaxy (HVPE). The root-mean-square (RMS) roughness of an as-grown sample is less than 0.8 nm with a scan area of 5 × 5 µm2. The full widths at half maximum (FWHMs) of on-axis X-ray rocking curves are 453 arcsec rocking toward the direction and 485 arcsec rocking toward the direction. Semipolar GaN grown on CNTPS has shown better isotropy than that grown on m-plane sapphire so far. The defect density is significantly reduced owning to epitaxial lateral overgrowth (ELOG). It is worth noting that this technique is not only nonlithographic but also cost-effective for mass production compared with conventional ELOG.