Scanning tunneling microscopy studies of III-nitride thin film heteroepitaxial growth

The current status of studies and new trends in obtaining and exploring surface characteristics of III-nitride semiconductors are analyzed and reviewed. Using a unique setup combining a scanning tunneling microscope (STM) with an inline molecular-beam epitaxy (MBE) chamber, the surface atomic structures on both hexagonal and cubic GaN films grown by nitrogen-plasma-assisted MBE have been studied \it{in situ} over a broad range of temperatures and [N]/[Ga] ratios. Models of the observed surface phases are developed based on the comparative analysis of their atomic-resolution STM images and ab initio total energy calculations.