Vapor-liquid-solid-like growth of thin film SiC by nanoscale alternating deposition of SiC and NiSi₂

We propose a vapour-liquid-solid (VLS)-like growth by alternately depositing nanoscale precursors of film and liquid flux using a pulsed laser deposition system with rapid beam deflection (RBD-PLD). The nanoscale alternating deposition of NiSi₂ and SiC precursors on a 4H-SiC substrate at 1000 °C was found to suppress the formation of stacking faults and the carbon aggregates in the fabricated SiC films. As a result, the growth of high-quality 3C-SiC films having a flat surface with a step-and-terrace structure was achieved under the optimized conditions. The advantage of this process is that the required amount of the NiSi₂ flux can be much reduced as compared to in the conventional VLS process; e.g., it could be as small as 5 vol% in volume ratio to the thin film SiC in the present case. The high crystallinity of the fabricated 3C-SiC thin films was also supported by their high visible photocurrent response ratio. The mechanism of the vapour-liquid-solid (VLS)-like growth is also discussed.