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:
Mar. 14, 2000
Filed:
Sep. 01, 1998
Komatsu Electronic Metals Co., Ltd., Hiratsuka, JP;
Abstract
This invention provides a single-crystal manufacturing device which can perform the lifting of single crystals at a high speed, allowing single crystals with uniform qualities along their axes can be obtained. The method for manufacturing single crystals according to this invention are achieved by using a single-crystal manufacturing device provided with a combination of a heat shield plate 1 and an after-cooler 21. The heat shield plate 1, the thickness of the lower portion of which is 2-6 times that of a conventional heat shield plate, surrounds the single crystal 7 being lifted. The after-cooler 21 covers the top surface of the rim 1a of the heat shield plate 1 and encompasses the single crystal 7 being lifted. The amount of cooling water supplied to the after-cooler 21 is slowly increased until the time the single crystal is lifted to a preset length, and then the amount of cooling water is kept constant. By this means, the temperature gradients of the single crystal in the region near the solid-liquid boundary can be increased, and the shape of the single crystal lifted can be easily kept unchanged. Furthermore, the lifting speed of the single crystal is kept constant from the top to the bottom of the crystal. Compared with conventional methods, the single-crystal lifting speed can be multiplied by a value of 1.3-2.2. Therefore, single crystals with uniform qualities along their axes can be obtained.