Microstructural Characterization of InN Growth Process by RF-MBE

In this study, we investigated the generation process of anomalous growth regions on InN surface grown on GaN/sapphire template by the DERI (droplet elimination by radical beam irradiation) method using RF (radio frequency) – MBE (molecular beam epitaxy). The anomalous InN growth regions were observed in detail using TEM (transmission electron microscope) and classified into three regions. In the center of the anomalous growth region, there was no InN growth, while InN with a large thickness grew on the inner edge, and the thickness of the InN film on the outer edge increased toward the center. In addition, the dislocation type in the GaN template was discriminated between the abnormally grown and flatly grown InN regions, and it was found that the density of screw dislocations in the GaN template was larger in the abnormally grown InN region. The effects of In droplets on InN growth were classified into three regions, and the formation process of anomalous growth regions was discussed.