Silicon wafer and method for producing the same

Patent metadata

Field	Value
Publication number	US-9337013-B2
Application number	US-201214122356-A
Country	US
Kind code	B2
Filing date	May 14, 2012
Priority date	Jun 20, 2011
Publication date	May 10, 2016
Grant date	May 10, 2016

Abstract

Methods for producing a silicon wafer from a defect-free silicon single crystal grown by a Czochralski (CZ) method are provided. The methods comprise: preparing a silicon wafer obtained by slicing the defect-free silicon single crystal and subjected to mirror-polishing; then performing a heat treatment step of subjecting the mirror-polished silicon wafer to heat treatment at a temperature of 500° C. or higher but 600° C. or lower for 4 hours or more but 6 hours or less; and performing a repolishing step of repolishing the silicon wafer after the heat treatment step such that a polishing amount becomes 1.5 μm or more. Therefore, it is an object to provide a method by which a silicon wafer can be produced at a high yield, the silicon wafer in which Light Point Defects (LPDs) are reduced to a minimum, the silicon wafer with a low failure-incidence rate in an inspection step and a shipment stage.

First claim

The invention claimed is:

1. A method for producing a silicon wafer from a defect-free silicon single crystal grown by a Czochralski (CZ) method, the method comprising:
preparing the silicon wafer obtained by slicing the defect-free silicon single crystal and subjected to mirror-polishing; then
performing a heat treatment step of subjecting the mirror-polished silicon wafer to heat treatment at a temperature of 500° C. or higher but 600° C. or lower for 4 hours or more but 6 hours or less; and
performing a repolishing step of repolishing the silicon wafer after the heat treatment step such that a polishing amount becomes 1.5 μm or more, wherein
by performing the heat treatment step and the repolishing step, the silicon wafer in which the number of Light Point Defects (LPDs) that are 37 nm or more but 120 nm or less in particle diameter size, the LPDs detected by a particle counter, is 10/wafer or less is produced.

2. The method for producing a silicon wafer according to claim 1 , wherein
as the silicon wafer obtained by slicing and subjected to mirror-polishing, a silicon wafer of 300 mm or more in diameter is prepared.

Assignees

• Fusegawa Izumi
• Hoshi Ryoji
• Sonokawa Susumu
• Saito Hisayuki
• Shinetsu Handotai Kk

Inventors

• Fusegawa Izumi
• Hoshi Ryoji
• Sonokawa Susumu
• Saito Hisayuki

Classifications

• H10P36/03

  within silicon bodies · CPC title

• H10P90/129 Primary

  by polishing · CPC title

• H10P36/00 Primary

  Gettering within semiconductor bodies · CPC title

• H10D62/57

  the imperfections being on the surface of the semiconductor body, e.g. the body having a roughened surface · CPC title

• H10D62/50

  Physical imperfections · CPC title