A LIQUID-SOLUTION-PHASE SYNTHESIS OF CRYSTALLINE SILICON

A liquid-solution-phase technique for preparing submicrometer-sized silicon single crystals is presented. The synthesis is based on the reduction of SiCl4 and RSiCl3 (R = H, octyl) by sodium metal in a nonpolar organic solvent at high temperatures (385-degrees-C) and high pressures (>100 atmospheres). For R = H, the synthesis produces hexagonal-shaped silicon single crystals ranging from 5 to 3000 nanometers in size. For R = octyl, the synthesis also produces hexagonal-shaped silicon single crystals; however, the size range is controlled to 5.5 +/- 2.5 nanometers.