Micro-pulling-down

Contents

Basics

The micro-pulling-down (µ-PD) method is a crystal growth technique based on continuous transport of the melted substance through micro-channel(s) made in a crucible bottom. Continuous solidification of the melt is progressed on a liquid/solid interface positioned under the crucible. In a steady state, both the melt and the crystal are pulled-down with a constant (but generally different) velocity.

Many different types of crystal are grown by this technique, including Y3Al5O12, Si, Si-Ge, LiNbO3, α-Al2O3, Y2O3, Sc2O3, LiF, CaF2, BaF2, etc. [1][2]

Crystal growth routine

Standard routine procedure used in the growth of most of µ-PD crystals is well developed. The general stages of the growths include:

- charging of the crucible with starting materials (mixture of powders),

- heating of the crucible until starting materials in the crucible are completely melted,

- upward displacement of the seed until its contact with the meniscus or crucible,

- formation of the meniscus and partial melting of the seed top,

- correction of the shape of the meniscus through appropriate adjustment of crucible temperature and position of the seed crystal,

- crystal growth through puling of the seed in downward direction,

- separation of the as grown crystal from the meniscus,

- and cooling of the system (including the crystal and the crucible) to room temperature

See also

References

  1. ^ Fukuda, Tsuguo; Chani, Valery I (2007). T. Fukuda and V.I. Chani. ed. Shaped Crystals: Growth by Micro-Pulling-Down Technique. Berlin: Springer-Verlag. ISBN 3540712941. http://books.google.com/?id=Dc6PJEOvRv8C&printsec=frontcover. 
  2. ^ Yoshikawa, A.; Nikl, M.; Boulon, G.; Fukuda, T. (2007). "Challenge and study for developing of novel single crystalline optical materials using micro-pulling-down method". Opt. Mater. 30 (1): 6–10. Bibcode 2007OptMa..30....6Y. doi:10.1016/j.optmat.2006.10.030. 

External links