Apparatus for manufacturing silicon single crystal and melt inlet pipe of the same

Patent metadata

Field	Value
Publication number	US-10415150-B2
Application number	US-201715677368-A
Country	US
Kind code	B2
Filing date	Aug 15, 2017
Priority date	Sep 6, 2016
Publication date	Sep 17, 2019
Grant date	Sep 17, 2019

Abstract

An apparatus for manufacturing a silicon single crystal is provided. The apparatus comprises a chamber ( 11 ), a quarts crucible ( 21 ) provided in the chamber so as to be rotatable and movable upward and downward and store a silicon melt, a first heater ( 25 ) for melting a silicon raw material stored in the crucible, and a pulling mechanism ( 32 ) provided in the chamber so as to be rotatable and movable upward and downward. The pulling mechanism has a lower end to which a seed crystal (S) is attached. The seed crystal is to be dipped in the silicon melt in the crucible and pulled upward for growing a silicon single crystal by a Czochralski method. The apparatus further comprises a melt supplying mechanism ( 50 ) for supplying an additional silicon melt to the silicon melt in the crucible from external of the chamber. The melt supplying mechanism includes a melt inlet pipe ( 51 ) disposed at an inclination angle θ1 of 50° to 80° with respect to the melt surface of the silicon melt and a melt generating mechanism ( 54 ) for supplying the additional silicon melt (M) to an opening part ( 512 ) of a base end of the melt inlet pipe. The melt inlet pipe has a tip end provided with an opening part ( 511 ). The opening part of the tip end has an annular surface inclined at an angle θ 2 with respect to a direction orthogonal to the axis of the melt inlet pipe. The annular surface has a vertically lower side ( 511 a ) and a vertically upper side ( 511 b ). The vertically lower side is located nearer to the tip end in the axis direction than the vertically upper side.

First claim

What is claimed is:

1. An apparatus for manufacturing a silicon single crystal, comprising:
a chamber;
a crucible provided in the chamber so as to be rotatable and movable upward and downward, the crucible storing a silicon melt;
a first heater for melting a silicon raw material stored in the crucible;
a pulling mechanism provided in the chamber so as to be rotatable and movable upward and downward, the pulling mechanism having a lower end to which a seed crystal is attached, the seed crystal being to be dipped in the silicon melt in the crucible and pulled upward for growing a silicon single crystal by a Czochralski method; and
a melt supplying mechanism for supplying an additional silicon melt to the silicon melt in the crucible from external of the chamber,
the melt supplying mechanism comprising:
a melt inlet pipe of which a tip end portion is disposed at an inclination angle of 50° to 80° with respect to a melt surface of the silicon melt; and
a melt generating mechanism for supplying the additional silicon melt to an opening part of a base end of the melt inlet pipe,

wherein the tip end portion of the melt inlet pipe includes a tip end provided with an opening part, the opening part of the tip end having an annular surface inclined at an angle with respect to a direction orthogonal to an axis of the melt inlet pipe, the annular surface having a vertically lower side and a vertically upper side, the vertically lower side being located nearer to the tip end in the axis direction than the vertically upper side,
wherein the melt generating mechanism comprises:
a subchamber provided so as to be movable upward and downward, and to be rotatable about a vertical axis;
a container provided in the subchamber so as to be rotatable in a tilting manner;
a raw material hopper provided so as to be movable upward and downward and supplying an additional silicon raw material to the container; and
a second heater for melting the additional silicon raw material put in the container,

wherein the additional silicon raw material is supplied from the raw material hopper to the container and the additional silicon raw material supplied to the container is melted into the additional silicon melt by the second heater, and
wherein, in a state in which the melt inlet pipe is moved to the forward position by the moving mechanism, the subchamber is rotated about the vertical axis and is connected to the base end of the melt inlet pipe, and the container is rotated in the tilting manner to supply the additional silicon melt in the container to the opening part of the base end of the melt inlet pipe.

2. The apparatus for manufacturing a silicon single crystal according to claim 1 , wherein
the inclination angle of the tip end portion of the melt inlet pipe is set at 60° to 75° when a supplying amount of the additional silicon melt by the melt inlet pipe is 50 kg±10 kg,
the inclination angle of the tip end portion of the melt inlet pipe is set at 50° to 80° when the supplying amount of the additional silicon melt by the melt inlet pipe is 100 kg±10 kg,
the inclination angle of the tip end portion of the melt inlet pipe is set at 50° to 60° when the supplying amount of the additional silicon melt by the melt inlet pipe is 150 kg±10 kg,
the inclination angle of the tip end portion of the melt inlet pipe is set at 55° to 77.5° when the supplying amount of the additional silicon melt by the melt inlet pipe is 60 kg to 90 kg, and
the inclination angle of the tip end portion of the melt inlet pipe is set at 50° to 70° when the supplying amount of the additional silicon melt by the melt inlet pipe is 110 kg to 140 kg.

3. The apparatus for manufacturing a silicon single crystal according to claim 2 , further comprising:
a bellows having one end and other end and surrounding the melt inlet pipe, the one end being provided at a through hole formed in the chamber, the melt inlet pipe being to be inserted into the through hole, the other end being provided at the base end of the melt inlet pipe; and
a moving mechanism for supporting the melt inlet pipe so that the melt inlet pipe is movable between a forward position at which the melt inlet pipe penetrates the chamber and the tip end of the melt inlet pipe is close to the melt surface in the crucible and a backward position at which the melt inlet pipe is located outside the chamber, the moving mechanism moving the melt inlet pipe between the forward position and the backward position,
wherein a distance between the base end of the melt inlet pipe and the chamber in the forward position is less than the distance between the base end of the melt inlet pipe and the chamber in the backward position.

4. The apparatus for manufacturing a silicon single crystal according to claim 3 , wherein, after the additional silicon melt in the container is supplied to the crucible through the melt inlet pipe, connection between the subchamber and the opening part of the base end of the melt inlet pipe is released and the melt inlet pipe is moved from the forward position to the backward position.

5. The apparatus for manufacturing a silicon single crystal according to claim 1 , further comprising:
a bellows having one end and other end and surrounding the melt inlet pipe, the one end being provided at a through hole formed in the chamber, the melt inlet pipe being to be inserted into the through hole, the other end being provided at the base end of the melt inlet pipe; and
a moving mechanism for supporting the melt inlet pipe so that the melt inlet pipe is movable between a forward position at which the melt inlet pipe penetrates the chamber and the tip end of the melt inlet pipe is close to the melt surface in the crucible and a backward position at which the melt inlet pipe is located outside the chamber, the moving mechanism moving the melt inlet pipe between the forward position and the backward position,
wherein a distance between the base end of the melt inlet pipe and the chamber in the forward position is less than the distance between the base end of the melt inlet pipe and the chamber in the backward position.

6. The apparatus for manufacturing a silicon single crystal according to claim 5 , wherein, after the additional silicon melt in the container is supplied to the crucible through the melt inlet pipe, connection between the subchamber and the opening part of the base end of the melt inlet pipe is released and the melt inlet pipe is moved from the forward position to the backward position.

7. The apparatus for manufacturing a silicon single crystal according to claim 1 , wherein the melt inlet pipe comprises a straight body.

8. The apparatus for manufacturing a silicon single crystal according to claim 1 , wherein:
the melt inlet pipe comprises a straight body, and
the straight body is disposed in a through hole opened at a wall of the chamber at the inclination angle of 50° to 80° with respect to the melt surface of the silicon melt.

Assignees

• Sumco Corp

Inventors

• Hayashi Mitsuaki
• Sugimura Wataru
• Shimozaki Ippei

Classifications

• Y10T117/1056

  including details of precursor replenishment · CPC title

• C30B15/10

  Crucibles or containers for supporting the melt · CPC title

• C30B29/06

  Silicon · CPC title

• C30B15/12

  Double crucible methods · CPC title

• C30B15/02 Primary

  adding crystallising materials or reactants forming it in situ to the melt · CPC title