[24p-P04-1~9] 15.4 III-V-group nitride crystals

[24p-P04-9] First-principles study for structural stability of GaN layers on AlN(0001) surface

〇(M1)Haruka Sokudo¹, Toru Akiyama¹, Tomonori Ito¹ (1.Mie Univ.)

Keywords:nitride semiconductor, Crystal growth, First-principles calculation

The thickness dependence of surface structure and stability in GaN layers grown on AlN(0001) is investigated based on first-principles calculations. The absolute surface energy of GaN layers on AlN(0001) surface is calculated by the wedge-shape geometry method considering various structures as surface reconstruction, and the effects of GaN film thickness on the surface structural stability and the absolute surface energy of GaN are discussed. The surface structural stability changes depending on the Ga chemical potential. The surface structure and absolute surface energy do not change significantly for GaN layers with more than 2 bilayers, suggesting that the surface stability does not depend on the film thickness. In my lecture, I will also discuss the results of calculations on the behavior of adsorption and desorption of atoms on surfaces.