Semi-Polar InGaN-Based Green Light-Emitting Diodes Grown on Silicon

Abstract

High-quality semi-polar (11-22) GaN is obtained by means of growth on patterned (113) silicon substrates featured with stripy grooves and extra periodic gaps which are perpendicular to the grooves. Ga melting-back during the GaN growth at a high temperature is eliminated as a result of special patterning design. On-axis X-ray rocking curve measurements show that the linewidth is significantly reduced down to 339 arcsec. Photoluminescence (PL) measurements at 10 K show strong GaN band-edge emission only, meaning that any basal stacking fault-related emission is not observed. Furthermore, green InGaN/GaN light-emitting diodes (LEDs) with an emission wavelength of around 530 nm are achieved on the semi-polar GaN grown on the patterned Si substrates. Excitation power-dependent PL measurements do not show a shift in wavelength, meaning a significant reduction in polarization-induced piezoelectric fields. Electroluminescence (EL) measurements exhibit that the output power of the semi-polar LED increases linearly with increasing injection current. It is worth highlighting that the overgrowth technology on designed patterned (113) silicon is a potential approach to manufacturing high-performance semi-polar GaN emitters on Si substrates in a long wavelength region.