Chip manufacturing is extremely demanding on the quality of raw silicon wafers, especially in terms of purity, defect density, dislocation, impurity (oxygen, carbon, metal ions) content. Quartz crucible is the key consumable of semiconductor silicon wafer raw material production.
As a quartz crucible carrying polysilicon molten material, it is in direct contact with silicon and its molten liquid, especially in the high temperature (1,420℃) production environment, its purity, strength, thermal properties, bubble content, surface state and other aspects of performance level have a great impact on the quality, yield and consistency of semiconductor silicon wafers. Compared with the solar quartz crucible, the semiconductor quartz crucible has more stringent requirements for the impurity content of the raw quartz sand in the production process, and the ash standard of the graphite electrode, the chemical liquid used in the production, the coating material and the grade of pure water are also higher at different inner positions.
The purity of the semiconductor quartz crucible, the control level of trace elements, the division of the bubble layer, the thermal properties, the degree of chemical reaction between the inner surface and the silicon liquid will greatly affect the microstructure, electrical properties, and the yield, stability and consistency of the product. The high-quality semiconductor quartz crucible needs to achieve a perfect balance in the various technical parameters.
The semiconductor industry is a strategic and basic industry that supports social and economic development and guarantees national security. With the rise of artificial intelligence, the Internet of Things, and cloud computing, the requirements for high-performance chips will be further improved, and the performance level and size requirements for semiconductor silicon wafers are also constantly improving.
Large size and high purity semiconductor quartz crucible will occupy the mainstream
At the performance level, high-end chips have more stringent requirements for technical indicators such as silicon surface micro-roughness, silicon single crystal defects, metal impurities, crystal primary defects, and surface particle size. The technological innovation of semiconductor silicon wafer industry chain has also put forward higher requirements for semiconductor quartz crucible products in terms of size, tolerance, black spot, impurity level and so on.
In addition, semiconductor manufacturing is moving toward "larger silicon wafers" and "smaller processes" to reduce manufacturing costs and power consumption. At present, the mainstream is 8 inch /12 inch silicon wafers, and under the high-intensity research and development investment of domestic semiconductor head enterprises, the research and development of key technologies of domestic 12 inch silicon wafers has made great progress, and advanced process silicon technology is accelerating breakthroughs. The increasing size of the downstream semiconductor silicon wafer industry has increased the demand for large-size and high-purity semiconductor quartz crucible.