In situ HREM observation of nucleation and growth of nanotwins beneath the solid-liquid interface in Si

Nucleation and growth of nanotwins in Si grown from Al-Si liquid have been observed directly using an in situ heating experiment in a high-resolution transmission electron microscope. Nanotwins are nucleated at the triple point between a vacuum and the solid-liquid interface. When two parallel twins, the mirror planes of which are separated slightly, encounter each other, very complicated atomic arrangements are formed. The structure of the perturbed region is discussed tentatively in terms of the high-pressure phases in Si.