Effect of lattice defects on the property of GaN crystal: A molecular dynamics simulation study

Understanding the property of defect-containing Gallium nitride (GaN) crystal at the molecular level can be very helpful for its potential applications. In this paper, we study the effect of lattice defects on the property of GaN crystal by using all atom molecular dynamics (MD) simulations. Our simulation results show that the lack and addition of (Ga or N) atoms can both change the morphology and the property of GaN crystal, and the crystal structure can be totally destroyed when the void or substitution rate is very high. Moreover, we also compare the different roles of Ga and N atoms in the crystal property, and find that the system containing more N atoms is much more instable than that containing more Ga atoms. The present work provides the property of GaN structure under different situations from microscopic views, and could give useful guidelines on optimal design of GaN materials in experiments.