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

Abstract

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 NiSi2and 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 NiSi2flux 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 responseratio.Themechanism of the vapour-liquid-solid (VLS)-like growth is also discussed.