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:
Jan. 07, 2025
Filed:
Feb. 22, 2021
Shin-etsu Handotai Co., Ltd., Tokyo, JP;
Kiyotaka Takano, Annaka, JP;
Kosei Sugawara, Nishigo-mura, JP;
Hiroyuki Kamada, Nishigo-mura, JP;
Takahide Onai, Nishigo-mura, JP;
Tomohiko Ohta, Shirakawa, JP;
SHIN-ETSU HANDOTAI CO., LTD., Tokyo, JP;
Abstract
A single-crystal pulling apparatus including: a pulling furnace having a central axis; and a magnetic field generation device arranged around the pulling furnace and having superconducting coils, the apparatus applying a horizontal magnetic field to the molten semiconductor raw material, two coil axes in the two pairs of the superconducting coils are included in a single horizontal plane, and when a direction of lines of magnetic force at the central axis of the pulling furnace in the horizontal plane is determined as an X axis, a center angle α having the X axis between the two coil axes is 100 degrees or more and 120 degrees or less. This makes it possible to reduce the height of the coils, to raise the magnetic field center close to the melt surface of the semiconductor raw material, and to obtain a single crystal having a lower oxygen concentration than conventional single crystals.