OBJECTIVEIntroducing ultrasounds in a Photovoltaic silicon (PV Si) crystal growth furnace would be a real breakthrough for the PV Si industry. It would indeed open the way to both ultrasonic stirring and ultrasonic diagnostics, such as echography for the solidification-front control, and velocimetry in laboratory situations. A patent concerning the technical solution to introduce ultrasounds in the furnace has been jointly published by the LMFA and LCIPV teams. The LCIPV team is proposing a Carnot Energies du Futur project (AWINSI project), to which the present project is joined, and which aims at performing the first introduction of ultrasounds in a PV-Si growth furnace. Other stirring solutions are presently investigated at LCIPV and SIMAP EPM, in particular through the PHD of M. Chatelain, co-directed by V. Botton, LMFA, and M. Albaric, LCIPV. A low cost parametric optimization is proposed by relying on ambient temperature water models to investigate the hydrodynamics of the concerned stirring solutions; the approach is based on dimensional analysis and similarities for the comparison to be quantitative and efficient.
The present project is to extend this experimental modelling to the investigation of mass transfer at the wall through electrochemical methods. The MATEIS/CorrIS team has a strong expertise in the use of these methods, and has already collaborated with the LMFA team on former similar investigations. The approach would be at low risk but very innovative, since this would be the first use of this classical tool in the framework of mass transfer during crystal growth to model impurities segregation.
The project would in the same time be a framework for V. Tavernier PHD project, at LMFA, dedicated to the modelling of the VB2 furnace of the SIMAP-EPM team. The project is to develop a segregation module and a complete model of VB2, in which the acoustic stirring may be implemented.
RESULTS
Member's area