On the transient amorphous silicon structures during solid phase crystallization

By analyzing the solid phase crystallization (SPC) of amorphous silicon (a-Si) with the Johnson-Mehl-Avrami-Kolmogorov (JMAK) model, it was found that the crystallization kinetics was non-ideal, with indications of a non-constant nucleation rate. Detailed structural analysis of the a-Si material during SPC revealed an increasing bond angle distortion from the ideal crystalline silicon (c-Si) bond angle of 109.5°. In addition, infrared measurements indicated a change in SiSi bond polarizability, however its role in the SPC behavior is not clear. The increase in tensile stress, bond angle deviation and bond polarizability together with the increase in crystal fraction may suggest that these parameters could be correlated.