The influence of vibrations on melt flows during detached Bridgman crystal growth

• Modeling of flows in detached Bridgman crystal growth under vibrations is performed.
• Free surface oscillations demonstrate the presence of resonance response.
• Average flow is strong in the domains where pulsational flow is highly non-uniform.
• At frequencies close to resonances the flow is determined by Schlichting mechanism.
• The flow near meniscus is governed by the Marangoni effect.

The paper deals with the numerical investigation of melt flows during germanium crystal growth by the Bridgman method under high frequency vibrations of the crystal. According to the experimental setup the mathematical model takes into account the crystal detachment from the crucible walls and the existence of technological channel in the crucible. The modeling is based on the average approach. The study has shown that the crystal vibrations can substantially affect the melt flows. Near the resonance frequencies or when the vibration amplitude is high, a strong average flow generated in the technological channel could reach the crystal-melt interface. Thus, varying the vibration parameters we can change the intensity and localization of the melt flows which should affect the interface shape and the detachment stability and therefore the grown crystal properties.