Mechanisms of metal induced crystallization analyzed by in situ Rutherford Backscattering Spectroscopy

Metal induced crystallization (MIC) is a promising technique for low temperature thin film transistor fabrication and graphene synthesis. In MIC, a transition metal acts as seed for the crystallization of an amorphous group IV element. Bond screening near the interface and facilitation of nucleation are recently discussed as mechanisms for MIC. So far, in situ studies have been performed using X-ray diffraction, which is sensitive to the degree of crystallinity but lacks depth resolution. A better insight into the MIC mechanisms requires depth resolved in situ studies in order to determine the concentration profiles of the diffusing components.

Here, the Si/Ag and C/Ni bilayer systems are studied. They are annealed at temperatures of up to 750 °C. Simultaneously, the layer composition and the compositional profiles are investigated with in situ Rutherford backscattering spectroscopy revealing the diffusion kinetics of the components. Both, the quick initial nucleation and the ensuing growth processes are investigated. Further characterization is performed employing in vacuo Raman spectroscopy revealing the phase structure of the resulting films and scanning electron microscopy to investigate the surface structure.