Characteristics of high-purity quartz raw materials for crucibles and exploration of key purification technologies

High-purity quartz serves as a crucial basic material for strategic emerging industries such as the new-generation information industry, new energy, and high-end equipment. The photovoltaic and semiconductor industries exhibit a robust demand for high-end high-purity quartz crucibles, and their quality requirements are becoming increasingly stringent. This paper conducts a comprehensive analysis of the industry requirements for high-purity quartz sand used in crucibles from multiple aspects, including purity, inclusions, particle size, and micro-morphology. Purity affects crucible thermal stability and optical properties; Inclusions reduce transparency and affect the thickness of transparent layer and bubble content; Good homogeneity is required in terms of particle size and morphology. On this basis, the characteristics of pegmatite-type and vein quartz-type high-purity quartz siliceous raw materials are overviewed. It is proposed that inclusions and lattice impurities are the key factors restricting the utilization of high-purity quartz crucibles. Moreover, the key technologies of high-purity quartz deep purification are systematically summarized, aiming to provide support for the optimization of high-purity quartz sand raw-material search and purification technologies.