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:
Oct. 06, 1992
Filed:
Jul. 19, 1990
Osaka Titanium Co., Ltd., Amagasaki, JP;
Kyushu Electronic Metal Co., Ltd., Saga, JP;
Abstract
An apparatus and a method for producing a silicon single crystal by the Czochralski method, whereby the silicon single crystal is pulled up from a crucible while the crucible is heated by a side heater in the lateral periphery of the crucible and a bottom heater facing the bottom of the crucible. The outputs of the side heater and bottom heater are controlled independently of each other so that an oxygen concentration in the pull-up direction of the pulled-up silicon single crystal is rendered uniform. In addition to the output control of the heaters, a magnetic field is applied to a molten liquid in the crucible, so that, a dopant concentration in a radial direction of the pulled-up silicon single crystal is rendered uniform.