The critical growth velocity for planar-to-faceted interfaces transformation in SiGe crystals

Abstract

Crystal-melt interface morphological transformation of differently oriented SiGe crystals with different Ge concentrations was observed, and the effect of Ge concentration on critical growth velocity (Vc) for the interface morphological transformation was investigated. A planar-to-faceted morphological transformation for the 〈110〉, 〈112〉, and 〈100〉 interfaces was observed. Vc for planar-to-faceted transformation of the 〈110〉, 〈112〉, and 〈100〉 interfaces decreases nonlinearly with increasing Ge concentration. SiGe faceted interfaces can be attributed to the fact that the perturbation induced in a planar interface was amplified when the constitutional undercooled zone was formed at high growth velocities.