IP Library Granted Patent US 7,977,219
Granted Patent B2
US 7,977,219 · App. 12/512,229 · Granted Jul 12, 2011

Manufacturing method for silicon wafer

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Quick Facts
Patent No.
US 7,977,219
App. No.
12/512,229
Granted
Jul 12, 2011
Kind
B2
Abstract

In a manufacturing method for a silicon wafer, a first heat treatment process is performed on the silicon wafer while introducing a first gas having an oxygen gas in an amount of 0.01 vol. % or more and 1.00 vol. % or less and a rare gas, and a second heat treatment process is performed while stopping introducing the first gas and introducing a second gas having an oxygen gas in an amount of 20 vol. % or more and 100 vol. % or less and a rare gas. In the first heat treatment process, the silicon wafer is rapidly heated to first temperature of 1300° C. or higher and a melting point of silicon or lower at a first heating rate, and kept at the first temperature. In the second heat treatment process, the silicon wafer is kept at the first temperature, and rapidly cooled from the first temperature at a first cooling rate.

Claims (30)

1. A manufacturing method for a silicon wafer comprising:

producing a silicon single crystal ingot grown by Czochralski process;

slicing the silicon single crystal ingot into plural silicon wafers;

performing a first heat treatment process on the silicon wafer while introducing a first gas having an oxygen gas in an amount of 0.01 vol. % or more and 1.00 vol. % or less and a rare gas, the first heat treatment process comprising:

rapidly heating the silicon wafer to a first temperature of 1300° C. or higher and a melting point of silicon or lower at a first heating rate; and

keeping the silicon wafer at the first temperature; and

after the first heat treatment process, performing a second heat treatment process on the silicon wafer while stopping introducing the first gas and instead, introducing a second gas having an oxygen gas in an amount of 20 vol. % or more and 100 vol. % or less and a rare gas, the second heat treatment process comprising:

keeping the silicon wafer at the first temperature; and

rapidly cooling the silicon wafer from the first temperature at a first cooling rate.

2. The manufacturing method for the silicon wafer according to claim 1 , wherein

the first heating rate is 10° C./sec or more and 150° C./sec or less and the first cooling rate is 10° C./sec or more and 150° C./sec or less.

3. A manufacturing method for a silicon wafer comprising:

producing a silicon single crystal ingot grown by Czochralski process;

slicing the silicon single crystal ingot into plural silicon wafers;

performing a first heat treatment process on the silicon wafer while introducing a first gas including a rare gas, the first heat treatment comprising:

rapidly heating the silicon wafer to a first temperature of 1300° C. or higher and the melting point of silicon or lower at a first heating rate;

keeping the silicon wafer at the first temperature;

rapidly cooling the silicon wafer to a second temperature of 800° C. or higher and 1000° C. or lower at a first cooling rate; and

keeping the silicon wafer at the second temperature; and

performing a second heat treatment process on the silicon wafer while stopping introducing the first gas and instead, introducing a second gas including an oxygen gas in an amount of 20 vol. % or more and 100 vol. % or less; the second heat treatment comprising:

keeping the silicon wafer at second temperature;

rapidly heating the silicon wafer from the second temperature to a third temperature of 1300° C. or higher and the melting point of silicon or lower at a second heating rate;

keeping the silicon wafer at the third temperature; and

rapidly cooling the silicon wafer from the third temperature at a second cooling rate.

4. The manufacturing method for a silicon wafer according to claim 3 , wherein

the first cooling rate is 20° C./sec or more and 150° C./sec or less and

the second heating rate is 20° C./sec or more and 150° C./sec or less.

5. The manufacturing method for the silicon wafer according to claim 4 , wherein

the first heating rate is 10° C./sec or more and 150° C./sec or less and

the second cooling rate is 10° C./sec or more and 150° C./sec or less.

Assignments (3)
CHANGE OF NAME Recorded Mar 13, 2013
From: COVALENT SILICON CORPORATION
To: GLOBALWAFERS JAPAN CO., LTD.
Reel/Frame 029991/0421 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Mar 11, 2013
From: COVALENT MATERIALS CORPORATION
To: COVALENT SILICON CORPORATION
Reel/Frame 029962/0497 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Nov 12, 2009
From: ISOGAI, HIROMICHI; SENDA, TAKESHI; TOYODA, EIJI; MURAYAMA, KUMIKO; IZUNOME, KOJI; MAEDA, SUSUMU; KASHIMA, KAZUHIKO
To: COVALENT MATERIALS CORPORATION
Reel/Frame 023506/0280 →