Growth and characterization of a-plane (1120) GaN films on (010) LiGaO ₂ substrate by chemical vapor deposition

Nonpolar (1120) GaN films were successfully grown on closely lattice-matched (010) LiGaO₂ (LGO) substrates by chemical vapor deposition (CVD) method. The dependence of growth characteristics on the growth temperatures was investigated. The surface morphologies of GaN films were characterized by scanning electron microscopy. Structural properties of the GaN epilayers were investigated by X-ray diffraction and transmission electron microscopy. Cross-section transmission electron microscopy results showed direct evidence of the in-plane structural relationship between the GaN epilayer and (010) LGO substrate. Low temperature photoluminescence was dominated by neutral donor bound excitons emission at 3.472 eV and the defect-related yellow emission was negligible.