The crystallization of Al-Ge alloy amorphous thin films reveals a unique, dense branching morphology. Such morphology is found in other systems, i.e., electrodeposition and the Hele-Shaw cell, but so far this is the only known case in the field of materials science. A detailed description is given of the structure, morphology, and composition of the crystallized films and of the material processes that are involved in the crystallization of the Al-Ge alloy, and which are responsible for the unique morphology. The role played by diffusion is particularly emphasized.

• Received 24 June 1991

DOI:https://doi.org/10.1103/PhysRevA.44.8316