Structural characterization of thick (1122) GaN layers grown by HVPE on m-plane sapphire
This paper reports structural characterization of thick equation image-oriented GaN layers by means of XRD, TEM, and micro- CL. The semi-polar equation image GaN layers were grown on m-plane sapphire substrates by HVPE. Their structural quality improved with thickness. Threading dislocation density of 3 x 108 cm-2 and stacking faults density of 4 x 104 cm-1 were measured at the surface of 20 µm thick (1122) GaN layers. The semi-polar GaN layers were used as template substrates to grow InGaN/GaN MQW heterostructures by MOCVD that demonstrated optically pumped lasing at 500 nm wavelength. The results demonstrate the longest wavelength yet reported for a photo-pumped laser on template substrates.
Usikov, A.; Shapovalova, L.; Strittmatter, A.; Johnson, N. M.; Ivantsov, V.; Syrkin, A.; Soukhoveev, V.; Scanlan, B.; Zheng, J. G.; Spiberg, P.; El-Ghoroury, H. Structural characterization of thick (1122) GaN layers grown by HVPE on m-plane sapphire. physica status solidi (a). 2010 June; 207 (6): 1295-1298.