Quartz sand is an affordable inexpensive raw material for technologies of electronics and photovoltaics

Abstract

Based on the analysis of modern methods for obtaining semiconductor silicon, critical factors influencing the prospects for the development of the industry are identified. The basic component of the production scheme for producing silicon of semiconductor quality today is the carbothermal technology for producing metallurgical silicon. The dominance of this scheme is largely dictated by economic reasons for the development of capital-intensive industries. The accumulation of objective needs over time predetermine the need to overcome the inertial barrier of evolutionary steps in the development of semiconductor quality silicon technology.
 First of all, the problems of raw material supply and high energy intensity of traditional production processes are actualized. The task is formulated in the direction of searching for a source of raw materials that removes in the time perspective the problems of ensuring a potential increase in the volume of production of semiconductor quality silicon, as well as the problems of energy supply for this growth process. As a promising solution, a method is proposed for obtaining silicon of semiconductor quality directly from quartz sand, excluding the use of expensive and scarce quartzites and charcoal. The prospects for quartz sand as a raw material replacing quartzite are objectively predetermined by the high similarity of the physicochemical characteristics of these materials. The objective prerequisites for the process of replacing quartzite are supported by the existing practice of testing the proposed technological solutions on an industrial scale.For this purpose, low energy-intensive processes for the production and purification of silanes, utilization and reversal of intermediate technological products are used. The energy efficiency of the method is ensured by the exclusion from the technology of a large-tonnage, energy-intensive process for obtaining metallurgical silicon, as well as energy-consuming methods associated with the use of low temperatures (–30 ... –80 ° C). The technological solution eliminates the need for the synthesis of hydrogen chloride and, accordingly, eliminates the explosive high-temperature process from production. The proposed solutions open up possibilities for the variable use of known technologies in relation to the current consumer requirements for the quality of polycrystalline silicon.