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:
Apr. 21, 1987
Filed:
Apr. 28, 1986
Kyong-Min Kim, Hopewell Junction, NY (US);
Pavel Smetana, Poughkeepsie, NY (US);
Wolfgang A Westdorp, Hopewell Junction, NY (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
An improvement in the method and apparatus for growing a semiconductor crystal by the Czochralski technique comprising the steps of applying a rotating transverse magnetic field to molten semiconductor material held in a crucible during the seed crystal pulling and crystal formation step, to cause the molten material to rotate within the crucible, and simultaneously increasing the rotational velocity of the magnetic field during this crystal formation as a function of the length of the crystal pulled from said molten material to thereby vary the rotation rate of the molten material. These steps result in the uniform axial distribution of oxygen in the crystal.