Richard L. Longini

Growth of Atomically Flat Surfaces on Germanium Dendrites

This note presents a theory of the formation of extended flat surfaces on germanium dendrites. It is suggested that part of the liquid‐solid interface is a supercooled {111} surface, on which new atomic planes are occasionally nucleated. Thermal limitations on the nucleation and propagation of these monolayers are discussed. When such a growing layer reaches the melt surface it creates a step on the solid. It is proposed that the meniscus momentarily sticks to the corner of this step. Subsequent planes nucleated during this sticking period result in a step several atomic layers high, in accord with experiment. Elementary estimates of corner energy and amount of meniscus sticking yield results consistent with experiment.