Czochralski crystal growing systems

They are characterized by:

• Precision: Precisely manufactured drive units enable reproducible process control as well as the production of the best possible crystal qualities
• Robustness: Chamber components are made of high-quality stainless steel with highly polished inner surfaces to meet the highest requirements for durability and contamination level
• Safety: A high degree of automation and redundant safety systems allow the use in state-of-the-art production environments
• Customization: Thanks to many years of development expertise and variable components, PVA Crystal Growing Systems is ideally positioned to find optimum solutions for customer-specific requirements
• Support & Service: Spare parts service, adaptation & optimization of systems through direct contact with PVA TePla experts

What started by chance with the accidental dipping of a pen into molten tin is today the most important crystal growing process in microelectronics, which is the base for the rapid digital transformation of industry, science and society. The Czochralski process, named after Jan Czochralski and technically fully developed for industrial production, is currently used to produce silicon crystals up to 300 mm in diameter and a weight of 500 kg.  For this purpose, high-purity silicon is melted in a quartz crucible at approx. 1410 °C and the single-crystalline silicon ingot is pulled out of the melt by subsequent dipping of a seed crystal by means of controlled solidification.

The increasingly demanding requirements of modern microelectronics are characterized by ever higher integration density and permanent reduction of structure widths - while cost pressure remains the same. The resulting increase in productivity with a simultaneous increase in material quality must be achieved by specifically adjusting the type and distribution of crystal defects. These conditions must be precisely adjusted and controlled throughout the entire process, which places the highest demands on the puller, control and feedback control systems. Additional possibilities of influencing the convection flows in the melt, gas flows in the process chamber and temperature gradients at the solidification front and in the cooling crystal pose challenges for the system manufacturer.

PVA TePla operates its own development laboratory where, in close cooperation with research institutes, the latest topics for system and process development are worked on, applied and tested. Every newly developed system type is subjected to intensive testing here, as are all the associated accessories. This applies not only to the Czochralski technology development, but also to the entire product portfolio of PVA TePla.