The triangular pits eliminate of (11(2)over-bar0) a-plane GaN growth by metal-orgamic chemical vapor deposition

Nonpolar a-plane (11 (2) over bar0) GaN has been grown on r-plane (1 (1) over bar 02) sapphire by metal-orgamic chemical vapor deposition. The crystal quality has been greatly improved by using the AlGaN multiple-quantum-well interlayers. The surface morphology and the crystal quality were investigated by high resolution X-ray diffraction and atomic force microscopy. The triangular pits were eliminated completely. The precession of the X-ray diffraction symmetric reflection peak full with width at half maximum of (11 (2) over tilde0) is 680 ".