Effects of melting parameters and quartz purity on silica glass crucible produced by arc method

Abstract

In photovoltaic industry, silica crucible has an important influence on the quality of single crystal silicon. To obtain a silica glass crucible with large diameter, high uniformity, and low bubble content, two series of crucibles were prepared by the arc melting method, one with various melting parameters (initial power, melting power, and melting time) and crucible sizes, and the other with various quartz purities. The bubbles inside the crucible wall and pores on the inner surface were all measured using a polarised optical microscope and a portable microscope. The results show that all crucibles have a bubble aggregation area in their inner surface (0-0.4 mm), in which the density and size of bubbles are affected by melting time, melting power, and the distance between the crucible and the graphite electrode. The uniformity of the crucible decreases as the crucible diameter increases (16-28 inches), and the crucible is relatively stable when the initial power is below 400 kW. In final, a silica crucible with large size (diameter of 28 inches) and low bubble content on inner surface (∼50% reduction than that of traditional crucibles) was successfully prepared, which is of great value to the photovoltaic industry.

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

“…The total impurity content must be kept below 300 ppm to meet the stringent manufacturing standards for photovoltaics, where such controls are particularly critical. To address these demands, the utilization of high-purity quartz sand as a foundational raw material for quartz crucibles has emerged as an ideal choice, primarily due to its outstanding heat-resistant properties [27]. It is noteworthy that both quartz crucibles and crystalline silicon materials fall within the category of silica-based materials.…”

Silicon Solar Cells: Trends, Manufacturing Challenges, and AI Perspectives

“…Currently, quartz crucibles are the sole option available to the industry. It has been demonstrated that larger crucibles carry a higher risk of defects, leading to reduced mechanical stability at high temperatures [89].…”