MOVPE homoepitaxial growth on vicinal GaN(0001) substrates

Homoepitaxial growth of GaN by metal organic vapor phase epitaxy (MOVPE) was systematically evaluated using nominal c-plane and various vicinal GaN(0001) wafers: 1°, 2°, 4°, and 8° offcut in the directions of (1010) and (1120). It was found that a hillock morphology formed on the nominal c-plane substrate whereas smooth epi films were formed on vicinal substrates. Silicon-doped films showed similarly improved surface morphology with offcut angle, however Mg-doped films exhibited a rougher microstructure.