抄録
Spherical silicon can be produced directly by passing molten silicon through capillary with pressurized inert gas. Molten silicon passing through capillary forms jet and the jet is split into droplets by the hydrodynamic instability. This method can produce spherical silicon at ultra-high speed (600-1000 of spherical silicon per second). Spherical silicon produced by this method are known to be generally polycrystalline. Some of spherical silicon consist of 2-4 grains. In this report, we find that the generation probability of spherical silicon with 2-4 grains increased with decreasing cooling rate of spherical silicon. In the early condition of dropping spherical silicon, the cooling rate of spherical silicon was estimated to be between 600 and 800℃/sec
