Very-high-frequency thermal microplasma jet for the rapid crystallization of amorphous silicon

The rapid crystallization of amorphous silicon utilizing a very-high-frequency (VHF) inductive coupling thermal microplasma jet of argon is demonstrated. Highly crystallized Si films were synthesized by adjusting the translational velocity of the substrate stage and flow rate of argon. The crystallization proceeded uniformly to the film depth. The H concentration in the films decreased from 1021 cm-3 to 1019 cm-3 with no marked increases in oxygen and nitrogen impurity concentrations and defect density. The crystallization of a-Si proceeded with time constants of ∼ 10 ms, which was 4–6 orders of magnitude slower than the laser-crystallization. The crystallization process is discussed in terms of the solidification from molten Si by the rapid local heating of a-Si.