Crystallization of Amorphous Si and Ge Whiskers

Abstract

Crystallization processes of amorphous Si (a-Si) and Ge (a-Ge) whiskers have been investigated by using differential thermal analysis (DTA) and X-ray diffraction. On the crystallization of the a-Si and a-Ge whiskers, the DTA peak temperature is 907 and 527°C at a heating rate of 20°C/min, the activation energy is about 5 and 2.3 eV, and the exothermic heat is about 4 and 3 kcal/mol, respectively. It is found that the energy difference between the amorphous and crystalline states is much smaller than the energy barrier for the crystallization in both cases of Si and Ge. Furthermore, from the observations on the crystallization of amorphous films, it can be concluded that the a-Si whisker is more stable than other amorphous semiconductor films.