Device for growing a flat single crystal from a seed crystal in a crystallisation solution and process for manufacturing this single crystal

Patent metadata

Field	Value
Publication number	US-10934632-B2
Application number	US-201716314792-A
Country	US
Kind code	B2
Filing date	Jun 30, 2017
Priority date	Jul 4, 2016
Publication date	Mar 2, 2021
Grant date	Mar 2, 2021

Abstract

A device for growing a flat single crystal from a seed in a crystallization solution. A support element has a support face; a blocking element comprising a blocking face, positioned at a predefined distance from the support face to block the growth of the single crystal in a direction perpendicular to the support face; a seed protection member, configured to protect the seed during a crystallization solution treatment phase and to free a growth zone positioned between the support face and the blocking face during a rotation of the support element; the blocking element comprises a holding member that cooperates with the protection member, the holding member being movable between a first position where it holds the protection member against the support face during the treatment phase and a second position where the holding member is separated from the protection member and participates in the formation of the blocking face.

First claim

What is claimed is:

1. A growth device for growing a planar single crystal from a seed crystal in a crystallisation solution, the growth device comprising:
a support element having a support face for supporting the seed crystal; and
a blocking element comprising a blocking face, the blocking face being disposed at a predefined distance from the support face so as to block growth of the single crystal in a substantially perpendicular direction to the support face;
wherein the growth device further comprises a protective member for protecting the seed crystal, configured to protect the seed from the crystallisation solution during a treatment phase of the crystallisation solution and to release a growth zone disposed between the support face and the blocking face upon rotating the support element;
the blocking element further including a holding member cooperating with the protective member, the holding member being movable between a first position in which it holds the protective member against the support face during the treatment phase and a second position in which the holding member is separated from the protective member and aids in forming the blocking face.

2. The device according to claim 1 , wherein the protective member is a hollow body defining an open cavity for covering the seed during the treatment phase.

3. The device according to claim 1 , wherein the blocking element includes a planar body a surface of which defines the blocking face, this body having a through hole which delimits an opening in the blocking face and wherein the holding member slides between the first and second positions.

4. The device according to claim 1 , wherein the holding member is a rod an end of which is provided with a planar surface having a shape corresponding to that of the opening in the blocking face.

5. The device according to claim 1 , wherein the protective member includes, on an external surface thereof, a flat forming a planar bearing surface against which the holding member bears in the first position.

6. The device according to claim 1 , wherein the support face and the blocking face are parallel to each other.

7. A facility for growing in solution a single crystal, comprising a vessel for containing a crystallisation solution, a growth device according to claim 1 , disposed in the vessel, and means for rotating the device in the vessel.

8. A process for manufacturing a single crystal by growth in solution from a seed crystal implemented using a facility according to claim 7 , the process comprising:
fixing the seed crystal to the support face of the support element, the seed crystal being oriented according to the orientation of the desired single crystal;
placing the protective member around the seed and holding it on the support face of the support element by pressing on the protective member through the holding member, which is placed in its first position;
contacting the protective member with the crystallisation solution by dipping the device into the crystallisation solution;
treating the crystallisation solution to obtain an under-saturated solution;
contacting the seed with the under-saturated crystallisation solution by moving the holding member from its first position to its second position and rotating the device about an axis essentially perpendicular to the support face, moving of the holding element and rotating, which releases the protective member;
modifying the temperature of the growth solution to obtain an over-saturated solution;
growing the single crystal between the support face and the blocking face from the over-saturated solution, this growth being continued until a desired lateral growth is obtained;
detaching the single crystal from the support face and the blocking face.

9. The manufacturing process according to claim 8 , wherein the single crystal is a single crystal of potassium dihydrogen phosphate (KDP) or deuterated potassium dihydrogen phosphate (DKDP).

Assignees

• Commissariat Energie Atomique

Inventors

• Vissie Pascal
• Grosil Max
• Pintault Bruno

Classifications

• Y10T117/1024

  for crystallization from liquid or supercritical state · CPC title

• C30B35/007

  Apparatus for preparing, pre-treating the source material to be used for crystal growth · CPC title

• C30B29/14

  Phosphates · CPC title

• C30B7/08

  by cooling of the solution · CPC title

• C30B15/32

  Seed holders, e.g. chucks · CPC title