Ab initio study for adsorption and desorption behavior at step edges of AlN(0001) and GaN(0001) surfaces

Abstract

The adsorption and desorption behavior of adatoms at step edges of AlN(0001) and GaN(0001) surfaces is investigated on the basis of ab initio calculations. Our calculations for single layer step edges along the [11̅00] direction reveal that the structure of the step edge depends on the growth condition. Furthermore, the adsorption behavior of adatoms close to the step edges is found to be dependent on the structure of step edges. The calculated results of adatom behavior suggests the possibility to control the morphology of GaN(0001) and AlN(0001) surfaces by growth parameters such as V/III ratio and temperature.