Method for producing a silicon single crystal doped with red phosphorous with reduced number of stacking faults and method for producing a silicon wafer using the same

Patent metadata

Field	Value
Publication number	US-10100429-B2
Application number	US-201515324856-A
Country	US
Kind code	B2
Filing date	Apr 8, 2015
Priority date	Dec 24, 2014
Publication date	Oct 16, 2018
Grant date	Oct 16, 2018

Abstract

A method for producing a single crystal includes: bringing a seed crystal into contact with a dopant-added melt, in which a red phosphorus is added to a silicon melt, such that a resistivity of the single crystal is 0.9 mΩ·cm or less and subsequently pulling up the seed crystal, to form a straight body of the single crystal; and withdrawing the single crystal from the dopant-added melt in a state that a temperature of an upper end of the straight body is 590 degrees C. or more.

First claim

The invention claimed is:

1. A method for producing a single crystal using a single-crystal pull-up apparatus comprising a chamber, a crucible disposed in the chamber and configured to receive a dopant-added melt in which red phosphorus is added to a silicon melt, and a pull-up section that is configured to pull up a seed crystal after bringing the seed crystal into contact with the dopant-added melt, the method comprising:
bringing the seed crystal into contact with the dopant-added melt, in which the red phosphorus is added to the silicon melt, such that a resistivity of the single crystal is 0.9 mΩ·cm or less and subsequently pulling up the seed crystal, to form a straight body having a length of 550 mm or less and a diameter of 200 mm;
forming a tail at a lower end of the straight body, the tail having a length in a range from 100 mm to 140 mm; and
withdrawing the single crystal from the dopant-added melt in a state that a temperature of an upper end of the straight body is 590 degrees C. or more so as to adjust an area of the straight body to have a predetermined length, a residence time of the area at the temperature of 570±70 degrees C. ranging from 20 minutes to 200 minutes.

2. A method for producing a single crystal using a single-crystal pull-up apparatus comprising a chamber, a crucible disposed in the chamber and configured to receive a dopant-added melt in which red phosphorus is added to a silicon melt, and a pull-up section that is configured to pull up a seed crystal after bringing the seed crystal into contact with the dopant-added melt, the method comprising:
bringing the seed crystal into contact with the dopant-added melt, in which the red phosphorus is added to the silicon melt, such that a resistivity of the single crystal is 0.9 mΩ·cm or less and subsequently pulling up the seed crystal, to form a straight body having a length of 550 mm or less and a diameter of 200 mm;
forming a tail at a lower end of the straight body, the tail having a length in a range from 100 mm to 180 mm; and
withdrawing the single crystal from the dopant-added melt so as to adjust an area of the straight body to have a predetermined length, a residence time of the area at the temperature of 570±70 degrees C. ranging from 20 minutes to 200 minutes.

3. The method for producing a single crystal according to claim 1 , wherein
the single crystal is produced plural times to produce a plurality of the single crystals,
the dopant-added melt in an amount capable of producing one of the plurality of single crystals is received in the crucible, and
each time one of the plurality of single crystals is produced, a silicon polycrystal material and the red phosphorus are added to the crucible to produce a next one of the plurality of single crystals.

4. The method for producing a single crystal according to claim 1 , wherein
the dopant-added melt in an amount capable of producing a plurality of single crystals is received in the crucible, and
the plurality of single crystals are produced one by one without adding a silicon polycrystal material and the red phosphorus to the crucible.

5. A method for producing a silicon wafer, comprising cutting off a silicon wafer from a straight body of a single crystal produced by the producing method of a single crystal according to claim 1 .

6. A method for producing an epitaxial silicon wafer comprising:
heating a silicon wafer produced by the producing method of a silicon wafer according to claim 5 in a hydrogen atmosphere in a first step; and
forming an epitaxial film on the silicon wafer after the first step to produce an epitaxial silicon wafer in a second step.

7. The method for producing a single crystal according to claim 2 , wherein
the single crystal is produced plural times to produce a plurality of the single crystals,
the dopant-added melt in an amount capable of producing one of the plurality of single crystals is received in the crucible, and
each time one of the plurality of single crystals is produced, a silicon polycrystal material and the red phosphorus are added to the crucible to produce a next one of the plurality of single crystals.

8. The method for producing a single crystal according to claim 2 , wherein
the dopant-added melt in an amount capable of producing a plurality of single crystals is received in the crucible, and
the plurality of single crystals are produced one by one without adding a silicon polycrystal material and the red phosphorus to the crucible.

9. A method for producing a silicon wafer, comprising cutting off a silicon wafer from a straight body of a single crystal produced by the producing method of a single crystal according to claim 2 .

10. A method for producing an epitaxial silicon wafer comprising:
heating a silicon wafer produced by the producing method of a silicon wafer according to claim 9 in a hydrogen atmosphere in a first step; and
forming an epitaxial film on the silicon wafer after the first step to produce an epitaxial silicon wafer in a second step.

11. The method for producing a single crystal according to claim 1 , wherein in the withdrawing of the single crystal, the single crystal is withdrawn from the dopant-added melt such that a yield in the straight body is 90% or more.

12. The method for producing a single crystal according to claim 2 , wherein in the withdrawing of the single crystal, the single crystal is withdrawn from the dopant-added melt such that a yield in the straight body is 90% or more.

Assignees

• Sumco Corp

Inventors

• Narushima Yasuhito
• Uto Masayuki
• Kubota Toshimichi

Classifications

• C30B15/04 Primary

  adding doping materials, e.g. for n-p-junction · CPC title

• C30B15/206

  the thermal history of growing the ingot · CPC title

• C30B25/20

  the substrate being of the same materials as the epitaxial layer · CPC title

• C30B25/02

  Epitaxial-layer growth · CPC title

• C23C16/0209

  by heating · CPC title