SINGLE CRYSTAL SILICON PRODUCTION METHOD, EPITAXIAL SILICON WAFER PRODUCTION METHOD, SINGLE CRYSTAL SILICON, AND EPITAXIAL SILICON WAFER

• US 20200135460A1
• Filed: 04/12/2018
• Published: 04/30/2020
• Est. Priority Date: 04/25/2017
• Status: Active Application

• Current Assignee: Sumco Corporation
• Original Assignee: Sumco Corporation
• Inventors: NARUSHIMA, Yasuhito, MAEGAWA, Koichi, OGAWA, Fukuo, KAWAKAMI, Yasufumi
• Application Number:
  US16/606,931
• Publication Number:
  US 20200135460A1
• Time in Patent Office: Days
• CPC Class Codes: C30B 15/04 adding doping materials, e.g. for n-p-junction
• CPC Class Codes: C30B 15/14 Heating of the melt or the crystallised materials
• CPC Class Codes: C30B 15/206 the thermal history of growing the ingot
• CPC Class Codes: C30B 25/02 Epitaxial-layer growth
• CPC Class Codes: C30B 25/186 being specially pre-treated by, e.g. chemical or physical means
• CPC Class Codes: C30B 25/20 the substrate being of the same materials as the epitaxial layer
• CPC Class Codes: C30B 29/06 Silicon
• CPC Class Codes: C30B 33/02 Heat treatment C30B33/04, C30B33/06 take precedence
• CPC Class Codes: H01L 21/02598 monocrystalline
• CPC Class Codes: H01L 21/324 Thermal treatment for modifying the properties of semiconductor bodies, e.g. annealing, sintering H01L21/20 - H01L21/288 and H01L21/302 - H01L21/322 take precedence

Abstract

A production method of a monocrystalline silicon includes adding red phosphorus in a silicon melt so that an electrical resistivity of the monocrystalline silicon falls in a range of 0.5 mΩ·cm or more and less than 0.7 mΩ·cm; and pulling up the monocrystalline silicon so that a time for a temperature of at least a part of a straight body of the monocrystalline silicon to be within a range of 570 degrees C. 70 degrees C. is in a range from 10 minutes to 50 minutes.

Claims

1. A production method of a monocrystalline silicon with use of a monocrystal pull-up apparatus, the apparatus comprising:

a chamber;

a crucible disposed inside the chamber and configured to receive a dopant-added melt comprising a silicon melt and red phosphorus added to the silicon melt; and

a pull-up unit configured to pull up a seed crystal after bringing the seed crystal into contact with the dopant-added melt, the method comprising;

adding the red phosphorus in the silicon melt so that an electrical resistivity of the monocrystalline silicon falls in a range of 0.5 mΩ

·

cm or more and less than 0.7 mΩ

·

cm; and

pulling up the monocrystalline silicon so that a time for a temperature of at east a part of a straight body of the monocrystalline silicon to be 570 degrees C.±

70 degrees C. is in a range from 10 minutes to 50 minutes.

4. A production method of an epitaxial silicon wafer, comprising:

a wafer-slicing step for slicing the monocrystalline silicon produced according to the production method according to claim 1 to produce a silicon wafer;

a hydrogen baking step for heating the silicon wafer in a hydrogen atmosphere; and

an epitaxial-film formation step for forming an epitaxial film on the silicon wafer.

5. The production method of an epitaxial silicon wafer according to claim 4, further comprising:

an argon-annealing step for applying a heat treatment on the silicon wafer prior to the hydrogen baking step, the heat treatment being performed in an argon gas atmosphere at 1200 degrees C. or more and 1220 degrees C. or less for 60 minutes or more and 120 minutes or less.

2. A production method of a monocrystalline silicon with use of a monocrystal pull-up apparatus, the apparatus comprising:

a chamber;

a crucible disposed inside the chamber and configured to receive a dopant-added melt comprising a silicon melt and red phosphorus added to the silicon melt;

a heating unit configured to heat the crucible; and

a pull-up unit configured to pull up a seed crystal after bringing the seed crystal into contact with the dopant-added melt, the method comprising;

a monocrystal-formation step in which the red phosphorus is added to the silicon melt so that an electrical resistivity of the monocrystalline silicon falls in a range of 0.5 mΩ

·

cm or more and less than 0.7 mΩ

·

cm, and the monocrystalline silicon is pulled up; and

a cooling step for cooling the monocrystalline silicon, wherein

in the cooling step, the monocrystalline silicon is pulled up by 400 mm or more within 180 minutes from separating the monocrystalline silicon from the dopant-added melt.

3. The production method of a monocrystalline silicon according to claim 2, wherein

in the cooling step, the monocrystalline silicon is pulled up with a power of the heating unit being half or less of the power of the heating unit immediately before starting the cooling step.

9. A production method of an epitaxial silicon wafer, comprising:

a wafer-slicing step for slicing the monocrystalline silicon produced according to the production method according to claim 2 to produce a silicon wafer;

a hydrogen baking step for heating the silicon wafer in a hydrogen atmosphere; and

an epitaxial-film formation step for forming an epitaxial film on the silicon wafer.

10. The production method of an epitaxial silicon wafer according to claim 9, further comprising:

an argon-annealing step for applying a heat treatment on the silicon wafer prior to the hydrogen baking step, the heat treatment being performed in an argon gas atmosphere at 1200 degrees C. or more and 1220 degrees C. or less for 60 minutes or more and 120 minutes or less.

6. A monocrystalline silicon comprising red phosphorus, electrical resistivity of the monocrystalline silicon being 0.5 mΩ

·

cm or more and less than 0.7 mΩ

·

cm, wherein

the monocrystalline silicon comprises a straight body comprising a crystalline region, a silicon wafer sliced from the crystalline region of the straight body having an LPD density of 90 nm or more of 2.5 per square centimeters or less on a surface of the silicon wafer, the LPD density being measured after applying a heat treatment in a hydrogen atmosphere at 1200 degrees C. for 30 seconds.

7. An epitaxial silicon wafer comprising:

a silicon wafer sliced from the crystalline region in the straight body of the monocrystalline silicon according to claim 6; and

an epitaxial film provided on the silicon wafer, wherein

the LPD density on a surface of the epitaxial film is 2.5 per square centimeters or less.

8. An epitaxial silicon wafer comprising:

a silicon wafer sliced from the crystalline region of the straight body of the monocrystalline silicon according to claim 6; and

an epitaxial film provided on the silicon wafer, wherein

the LPD density on a surface of the epitaxial film is 0.3 per square centimeters or less.