Study of silicon production processes and development of solar-cell fabrication technologies

Abstract

The methods of purification of "Kazsilicon" metallurgical silicon produced by the carbothermal method, i.e., the reduction of high purity Sary Kol quartz into carbon, are developed. These technologies provide the basis for the industrial production of silicon, solar cells, panels, and solar power plants. Using these technologies, solar grade silicon is produced, on the basis of which solar cells with an efficiency of 15.8-17.1% are fabricated. Panels of solar cells compose the "Astana Solar", i.e., the first solar power plant in Kazakhstan with a power of 250 kW, which was put into operation December 25, 2012.

Advanced Processing Techniques and Impurity Management for High-Purity Quartz in Diverse Industrial Applications

“…Solar cells are devices that convert sunlight into electricity, primarily by utilizing semiconductor materials to harness the generated electron-hole pairs through the photovoltaic process [23]. High-purity crystalline silicon, a semiconductor material, plays a pivotal role in solar cell manufacturing, serving as the foundation for both N-type and P-type silicon wafers used in solar cell fabrication [24]. The production of high-purity crystalline silicon for the photovoltaic industry involves a series of meticulous processes, including raw material selection, refining, crystal growth, and wafer slicing.…”

High-Tech Production of Photo-Energy in Kazakhstan Based on the Sarykol Quartz Deposit

“…(2) 2Mg + SiO 2 = Si + 2MgO (3) Theoretically, this allows you to remove Al, Ca and Mg to very low levels, but in practice this is hampered by large heat losses occurring during this operation. In order to avoid crystallization of the melt, oxygen is purged, as a result of which an exothermic oxidation of silicon to a dioxide occurs.…”

“…Table 1 shows the average value for the removal of Al and Ca in percent, for several issues both with and without fluxes. In the project implementation, an optimized slag purification technology using various fluxes, as well as purification by the crystallization method, was developed [3]. After conducting pilot tests, the SoG-Si obtained by the carbothermic method from the quartz of the Sarykol field after all stages of purification, as well as solar cells created from the material obtained, was investigated.…”