Solid-phase crystallization (SPC) of amorphous silicon (a-Si) under an external force field is investigated experimentally and numerically. Experimental results show that the kinetics of crystallization can be greatly enhanced by applying induction fields without the heating problems of a-Si film and its substrate, since temperature rises during the crystallization process are negligibly small. To explore the underlying acceleration mechanisms for the SPC process under the external fields, molecular dynamics simulations are carried out using the Tersoff potential. The numerical amorphous structure is obtained by the liquid quenching method and is utilized to simulate the crystallization processes at various process temperatures with and without external force fields. While homogeneous crystallization of a-Si could not be achieved readily, it is shown that the heterogeneous crystallization can be significantly accelerated by external force fields. This enhancement is due to increased molecular jumping frequencies associated with the molecular potential energies being increased by external excitations, rather than due to thermal mechanisms dominant in conventional SPC processes.

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We propose a new method for lower process temperature and shorter process time of SPC. This method involves the induction of high frequency alternating magnetic field during crystallization annealing, referring this process as Alternating Magnetic Field Crystallization, AMFC. The processed films were characterized using UV spectroscopy to determine the incubation time, Raman spectroscopy for the degree of crystallization. We found that the kinetics of crystallization was greatly enhanced by alternating magnetic field. When we crystallized, in the case of SPC, annealing time is over 14 hours at 570°C. But in the case of AMFC, annealing time is only 20minutes at the same temperature.