Theoretical Study of Line and Terraces Defects on GaN(0001) Surface

摘要

a vacancy line defects on the [1120] and [1010] direction; the GaN single-layer terraces defects of GaN(0001) surfaces are studied by first-principle calculations based on density functional theory. The surface energy, charge density, and Mulliken charge population of defect surfaces are calculated, and the surface geometries of before and after optimization for clean and defect surfaces are compared. Upon completion of the result calculation, it was revealed that the surface atoms of the line defect on the [1010] direction actually relax along the same direction. The stability of defect surface in the [1010] direction is better than that in the [1120] direction. The terraces surface on the [1120] direction is the most stable, which is consistent with the experimental observation. Terraces surface platform on the [1120] and [1010] directions are respectively inclination 0.7° and 0.2° towards the [1100] and [1210] direction. Terrace defects can enhance the surface metallicity, which is helpful for the adsorption of exotic particles.