Realization of Maskless Epitaxial Lateral Overgrowth of GaN on 3C-SiC/Si Substrates

By virtue of the poor nucleation of GaN on 3C-SiC, a maskless epitaxial lateral overgrowth (ELO) of GaN was realized on 3C-SiC/Si substrates to improve crystalline quality. The mechanism of the maskless ELO process was investigated by observing surface morphologies at different growth steps. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) confirmed that the grain size of GaN crystallites was increased in the three-dimensional ELO. As a result, the stress in the GaN epilayer decreased with the smaller number of grain boundaries in the coalescence process. The luminescent property was also improved with a decrease in defect density.