Crystal growth from melt in combined heater-magnet modules

  • Rudolph, P. (Leibniz Institute for Crystal Growth (IKZ)) ;
  • Czupalla, M. (Leibniz Institute for Crystal Growth (IKZ)) ;
  • Dropka, N. (Leibniz Institute for Crystal Growth (IKZ)) ;
  • Frank-Rotsch, Ch. (Leibniz Institute for Crystal Growth (IKZ)) ;
  • KieBling, F.M. (Leibniz Institute for Crystal Growth (IKZ)) ;
  • Klein, O. (Weierstrass-Institute for Applied Analysis and Stochastics (WIAS)) ;
  • Lux, B. (Leibniz Institute for Crystal Growth (IKZ)) ;
  • Miller, W. (Leibniz Institute for Crystal Growth (IKZ)) ;
  • Rehse, U. (Leibniz Institute for Crystal Growth (IKZ)) ;
  • Root, O. (Leibniz Institute for Crystal Growth (IKZ))
  • Published : 2009.10.31


Many concepts of external magnetic field applications in crystal growth processes have been developed to control melt convection, impurity content and growing interface shape. Especially, travelling magnetic fields (TMF) are of certain advantages. However, strong shielding effects appear when the TMF coils are placed outside the growth vessel. To achieve a solution of industrial relevance within the framework of the $KRISTMAG^{(R)}$ project inner heater-magnet modules(HMM) for simultaneous generation of temperature and magnetic field have been developed. At the same time, as the temperature is controlled as usual, e.g. by DC, the characteristics of the magnetic field can be adjusted via frequency, phase shift of the alternating current (AC) and by changing the amplitude via the AC/DC ratio. Global modelling and dummy measurements were used to optimize and validate the HMM configuration and process parameters. GaAs and Ge single crystals with improved parameters were grown in HMM-equipped industrial liquid encapsulated Czochralski (LEC) puller and commercial vertical gradient freeze (VGF) furnace, respectively. The vapour pressure controlled Czochralski (VCz) variant without boric oxide encapsulation was used to study the movement of floating particles by the TMF-driven vortices.


  1. S. Yesilyurt, S. Motakef, R. Grugel and K. Mazuruk, 'The effect of the traveling magnetic field (TMF) on the buoyancy-induced convection in the vertical Bridgman growth of semiconductors', J. Crystal Growth 263 (2004) 80
  2. Ch. Frank-Rotsch, P. Rudolph, O. Klein, P. Lange and B. Nacke, Patent DE 10 2007 028 548, WO 2008/155137
  3. P. Lange, D. Jockel, M. Ziem et al., Patent DE 10 2007028 547, WO 2008/155138
  4. P. Schwesig, M. Hainke, J. Friedrich and G. Mueller, "Comparative numerical study of the effects of rotating and travelling magnetic fields on the interface shape and thermal stress in the VGF growth of InP crystals", J. Crystal Growth 266 (2004) 224
  5. H. Kasjanow, B. Nacke, St. Eichler et al., "3D numerical modeling of asymmetry effects of a heater-magnet module for VGF and LEC growth under traveling magnetic fields", J. Crystal Growth 310 (2008) 1540
  6. N.V. Abrosimov, A. L$\ddot{u}$dge, H. Riemann and W. Schr$\ddot{o}$der, "Lateral photovoltage scanning (LPS) method for the visualization of the solid-liquid interface of Si$_1$$_x$Ge$_x$ single crystals", J. Crystal Growth 237-239 (2002) 356
  7. P. Rudolph, "Travelling magnetic fields applied to bulk crystal growth from the melt: the step from basic research to industrial scale", J. Crystal Growth 310 (2008) 1298
  8. A. Moreno, B. Quiroz-Garcia, F. Yokaichiya, V. Stojanoff and P. Rudolph, "Protein crystal growth in gels and stationary magnetic fields", Cryst. Res. Technol. 42 (2007) 231
  9. Ch. Frank-Rotsch, P. Rudolph, O. Klein et al., Patent DE 10 2007 028 548, WO 2008/155137
  10. A. Krauze, A. Muiznieks, A. M$\ddot{u}$hlbauer, Th. Wezel, L. Gorbunov, A. Pedchenko and J. Virbulis, "Numerical 2D modelling of turbulent melt flow in CZ system with dynamic magnetic fields", J. Crystal Growth 266 (2004) 40
  11. Th. Wetzel, "Die Schmelzstr$\ddot{o}$mung im Si-Czochralski-Proze$\beta$ unter dem Einflu$\beta$ elektromagnetischer Felder", Fortschritt-Berichte VDI, Reihe 9, Nr. 328 (2001) 1
  12. Ch. Frank-Rotsch and P. Rudolph, "Vertical gradient freeze of 4 inch Ge crystals in a heater-magnet module", J. Crystal Growth 311 (2009) 2294
  13. P. Rudolph, M. Ziem and P. Lange, Patent DE 10 2007020 239, WO 2007/122231
  14. O. Klein, Ch. Lechner, P.-E. Druet et al., "Numerical simulations of the influence of a traveling magnetic field, generated by an internal heater magnet module, on Czochralski crystal growth", Proc. Intern. Sci. Colloquium "Modelling for Electromagnetic Processing" (MEP 08), October 27-29, 2008 in Hanover, pp. 91
  15. P. Rudolph, Ch. Frank-Rotsch, F.-M. Kiessling et al., "Crystal growth in heater-magnet modules - from concept to use", in: Proc. Int. Scientific Colloquium Modelling for Electromagnetic Processing (MEP 08), October 27-29, 2008 in Hanover, p. 79
  16. Ch. Frank-Rotsch, D. Jockel, M. Ziem and P. Rudolph, "Numerical optimization of the interface shape at the VGF growth of semiconductor crystals in a traveling magnetic field", J. Crystal Growth 310 (2008) 1505
  17. E. Tomzig, J. Virbulis, W.v. Ammon, Y. Gelfgat and L. Gorbunov, "Application of dynamic and combined magnetic fields in the 300 mm silicon single-crystal growth", Mat. Sci. in Semicond. Processing 5 (2003) 347
  18. R. Lantzsch, I. Grants, O. P$\ddot{a}$tzold, M. Stelter and G. Gerbeth, "Vertical gradient freeze growth with external magnetic fields", J. Crystal Growth 310 (2008) 1518
  19. M. Jurisch, F. B$\ddot{o}$rner, Th. Bünger et al., "LEC- and VGF-growth of SI GaAs single crystals - recent developments and current issues", J. Crystal Growth 275 (2005) 283
  20. D.T.J. Hurle and R.W. Series, "The use of a magnetic field in melt growth" in: D.T.J. Hurle (ed.), Handbook of Crystal Growth, Vol. 2a (Elsevier, North-Holland 1994) p. 259
  21. P. Dold and K.W. Benz, "Rotating magnetic fields: fluid flow and crystal growth applications", Prog. Cryst. Growth Charact. Mater. 38 (1999) 7
  22. P. Rudolph and F.-M. Kiessling, "Growth and characterization of GaAs crystals produced by the VCz method without boric oxide encapsulation", J. Crystal Growth 292 (2006) 532
  23. B.-C. Sim, I.-K. Lee, K.-H. Kim and H.-W. Lee, "Oxygen concentration in the Czochralski-grown crystal with cusp-magnetic field", J. Crystal Growth 275 (2005) 455
  24. N. Dropka, W. Miller, R. Menzel and U. Rehse, "Numerical study on transport phenomena in a directional solidification process in the presence of travelling magnetic fields" (in press), doi:10.1016/j.jcrysgro.2009.09.016
  25. O. Klein, P.-E. Druet, Ch. Lechner et al., "Numerical simulation of Czochralski crystal growth under the influence of a traveling magnetic field generated by internal heater-magnet module (HMM)", J. Crystal Growth 310 (2008) 1523
  26. K. Kakimoto, "Modeling of fluid dynamics in the Czochralski growth of semiconductor crystals" in: G. M$\ddot{u}$ller, J.-J. Metois, P. Rudolph (eds.), Crystal Growth-from Fundamentals to Technology (Elsevier, Amsterdam, 2004) p. 169