Aluminium Induced Crystallization of Amorphous Germanium

Abstract

Crystallization morphologies and kinetic processes have been studied in amorphous germanium (a-Ge) films in contact with aluminium (Al) layers of various thickness. The well-known spherulitic crystallization has been observed in a-Ge/Al/a-Ge trilayers with Al layer thickness above 10 nm. The kinetics of this growth was followed by electrical conductivity measurement of the a-Ge/Al bilayer. In the case of the thinnest Al layer (below 4 nm) fibre-like Ge crystal growth was found. The measurement results suggest that the crystallization of the amorphous Ge layers was controlled by diffusion processes.