Abstract
In order to study the preparation of pure silicon by the reduction of its iodide with hydrogen, the proper conditions for production of silicon tetraiodide have at first been investigated. By reacting crude silicon with iodine vapor in a vertical quartz tube, silicon tetraiodide was prepared at temperatures between 400∼1050°C. It was found that the amount of products depends on the flow rate of iodine vapor. Silicon tetraiodide obtained at lower temperature is more higher in purity than those obtained at higher temperature. It was also found that the impurities were enriched in a wool-like residue. The exothermic reaction of this iodination was comfirmed by the observation of the difference of temperature between the inner and outer part of the reaction tube.
