The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 08, 2022
Filed:
Oct. 30, 2017
Sumco Corporation, Tokyo, JP;
Koichi Maegawa, Tokyo, JP;
Yasuhito Narushima, Tokyo, JP;
Yasufumi Kawakami, Tokyo, JP;
Fukuo Ogawa, Tokyo, JP;
SUMCO CORPORATION, Tokyo, JP;
Abstract
A silicon single crystal production method includes pulling up and growing a silicon single crystal from silicon melt containing red phosphorus as a dopant by Czochralski process. The silicon single crystal is intended for a 200-mm-diameter wafer. The silicon single crystal includes a straight body with a diameter in a range from 201 mm to 230 mm. The straight body includes a straight-body start portion with an electrical resistivity in a range from 0.8 mΩcm to 1.2 mΩcm. A crystal rotation speed of the silicon single crystal is controlled to fall within a range from 17 rpm to 40 rpm for at least part of a shoulder-formation step for the silicon single crystal.