Ingot puller apparatus having heat shields with voids therein

Patent metadata

Field	Value
Publication number	US-11873575-B2
Application number	US-202117496535-A
Country	US
Kind code	B2
Filing date	Oct 7, 2021
Priority date	Nov 30, 2020
Publication date	Jan 16, 2024
Grant date	Jan 16, 2024

Abstract

Ingot puller apparatus for preparing a single crystal silicon ingot by the Czochralski method are disclosed. The ingot puller apparatus includes a heat shield. The heat shield has a leg segment that includes a void (i.e., an open space without insulation) disposed in the leg segment. The heat shield may also include insulation partially within the heat shield.

First claim

What is claimed is:

1. An ingot puller apparatus for growing a single crystal silicon ingot from a melt of silicon, the apparatus comprising:
a puller housing defining a growth chamber;
a crucible disposed within the growth chamber for containing the melt of silicon;
a pulling mechanism for pulling the ingot from the melt along a pull axis; and
a heat shield disposed within the growth chamber, the heat shield defining a central passage for receiving the ingot as the ingot is pulled by the pulling mechanism, the heat shield comprising:
a leg segment that extends downward relative to the pull axis, the leg segment comprising a leg segment housing that defines a leg chamber;
insulation disposed within the leg chamber;
a ledge disposed in the leg chamber, the insulation being supported by the ledge, the insulation being separated from the leg segment housing by a gap, the gap being disposed above the ledge; and

a foot that extends from the leg segment at a distal end of the leg segment, wherein a distance between at least a portion of the foot and the pull axis is less than a distance between the leg segment and the pull axis; and
wherein the leg segment has a void formed therein, at least a portion of the void being disposed below the ledge.

2. The ingot puller apparatus as set forth in claim 1 wherein the void extends into the foot.

3. The ingot puller apparatus as set forth in claim 1 wherein the void is radially aligned with the insulation.

4. The ingot puller apparatus as set forth in claim 1 wherein the insulation is made of carbon, felt, or layered molybdenum.

5. The ingot puller apparatus as set forth in claim 1 wherein the leg segment housing is made of graphite.

6. The ingot puller apparatus as set forth in claim 1 wherein the void is at least partially disposed within the foot.

7. The ingot puller apparatus as set forth in claim 6 wherein the foot comprises a foot housing that defines a foot chamber, there being no insulation disposed within the foot chamber.

8. The ingot puller apparatus as set forth in claim 6 wherein the foot comprises a foot housing, the foot housing having a sidewall that is parallel to the pull axis.

9. The ingot puller apparatus as set forth in claim 6 wherein the foot comprises a lower sidewall and an upper sidewall, the lower sidewall and upper sidewall angling toward each other and forming an apex.

10. The ingot puller apparatus as set forth in claim 1 wherein the foot does not include a void formed therein.

11. The ingot puller apparatus as set forth in claim 1 comprising a cooling jacket that at least partially overlaps the heat shield along the pull axis, the cooling jacket being radially inward to the heat shield, the cooling jacket defining a central passage for receiving the ingot as the ingot is pulled by the pulling mechanism.

Assignees

• Globalwafers Co Ltd

Inventors

• Ke Jiaying
• Bhagavat Sumeet S
• Ryu Jaewoo
• Meyer Benjamin
• Luter William
• Hudson Carissima Marie

Classifications

• C30B15/10 Primary

  Crucibles or containers for supporting the melt · CPC title

• C30B15/08

  Downward pulling · CPC title

• C30B29/06

  Silicon · CPC title

• C30B35/002

  Crucibles or containers · CPC title

• Y10T117/1032

  Seed pulling · CPC title