Crystal growth melt flow control using magnetic fields
A contactless control of melt convection is important for many crystal growth technologies. Typically steady magnetic fields are used to damp such flows and, in particular, turbulent fluctuations. Active flow driving forces due to alternating magnetic fields can be of stabilizing character, too.
Physical modelling of Czochralski crystal growth
At laboratory scales model experiments are an often used approach to industrial processes such as the Czochralski crystal growth method. Due to the availability of suitable measuring techniques, the low melting alloy GaInSn, which is liquid at room temperature became meanwhile as de facto standard.
RGS process and free surface dynamics in liquid metal flows
The Ribbon Growth on Substrate (RGS) technology is a crystallization technique that allows direct and efficient casting of silicon wafers and sheets of advanced metal-silicide compounds. A reasonable level of stability and controllability of this process can however only be achieved with the help of tailored AC magnetic fields. In order to design theses fields and to understand their complex interaction with the melt flow, specialized numerical tools are required.
Electromagnetic melt flow control in Vertical Gradient Freeze (VGF) crystal growth
The impact of magnetic fields on the melt flow in different crystal growth
processes is studied in collaboration with other groups like:
Technische Universität Freiberg,
RGS Development Netherlands,
Fraunhofer-Institut für Integrierte Systeme und Bauelementetechnologie IISB Erlangen,