Micro-pulling-down
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 pulling of the seed in downward direction
- Separation of the as grown crystal from the meniscus
- Cooling of the system (including the crystal and the crucible) to room temperature
gollark: That also has a ton of connotations.
gollark: ***Ë***
gollark: We should all aim to be more correct™.
gollark: "Winning" is silly.
gollark: we spëke ënglïsh.
See also
- Crystal growth
- Czochralski process
- Float-zone silicon
- Flux method
- Laser-heated pedestal growth
- Shaping processes in crystal growth
- Verneuil process
- Lithium niobate
- Sapphire
- Scandium(III) oxide
- Yttrium aluminium garnet
References
- Fukuda, Tsuguo; Chani, Valery I (2007). T. Fukuda; V.I. Chani (eds.). Shaped Crystals: Growth by Micro-Pulling-Down Technique. Berlin: Springer-Verlag. ISBN 3-540-71294-1.
- 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.
This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.