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.

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

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