Microstructure analysis in strained-InGaN/GaN multiple quantum wells

The barrier thickness effect on the energy and microstructure properties of InGaN/GaN multiple quantum wells is investigated with Stillinger–Weber potential. The calculation indicates that the energy of a quantum well increases as the GaN barrier thickness rises, and that Ga–N and In–N bonds are shrunk with respect to those of random InGaN alloy. Moreover, a critical value of the barrier thickness exits. If the barrier thickness exceeds the critical value, the bond length of Ga–N in quantum wells reduces as a function of indium concentration. This singular behavior of Ga–N bond is analyzed with a force balance model.