Optimization of Argon Gas Flow Rate for High-Quality Germanium Crystal Growth in Czochralski Method

The quality of germanium crystals grown using the Czochralski method critically depends on growth conditions, particularly the flow rate of inert gases. Despite its importance, the impact of argon gas flow rate on the thermal field, melt convection, and resultant crystal quality has not been comprehensively studied. To bridge this gap, we employed computational fluid dynamics and finite element method analysis to investigate argon flow rates ranging from 1 to 30 L/min. Our results reveal that increasing the argon flow rate improves not only crystal cooling but also heightens thermal stress by approximately 15% and dislocation density by 25%, with significant freezing at the melt–crucible interface for higher rates. These findings suggest that gas flow rate optimization is key to minimizing defects and enhancing crystal quality. This study provides novel insights into the thermal and flow dynamics within a Czochralski germanium growth setup, offering practical guidance for semiconductor manufacturing.