“…However, a thin LT InSb buffer layer results in a large grain size and a low nucleation density, that leads to take too long time for the ARTICLE IN PRESS lateral growth of InSb islands and the quality of InSb layer becomes bad. So there exists the optimal thickness for the initial LT InSb buffer layer, that produce large lateral grain size and low nucleation density, and the lateral growth and coalescence of InSb islands will be promoted [15][16][17][18][19]. Based on the experimental results above, it is found that the 30 nm thick initial LT buffer layer is the optimal one for high-quality HT InSb layer.…”