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. 08, 1994
Filed:
Mar. 31, 1992
Masami Tatsumi, Hyogo, JP;
Shin-ichi Sawada, Hyogo, JP;
Sumitomo Electric Industries, Ltd., Osaka, JP;
Abstract
A Czochralski method using radiation intercepting members (1, 9) is used for manufacturing a single crystal such as compound semiconductors with a high production yield using a material having a low thermal conductivity or with a small temperature gradient in the pulling direction. In this method, a coracle (6) having an opening is provided in a melt contained in a crucible (3). A first member (1) is positioned on the coracle (6) to intercept heat radiation from the melt. A second member (9) supported by a crystal pulling shaft (8) is positioned on the first member (1) to cover an opening formed at the center of the first member (1). Seeding is performed while heat loss is limited by intercepting the radiation with the first and the second members. After the seeding, a shoulder portion of a single crystal is formed while heat loss is still limited while intercepting the radiation with the members (1, 9). A cylindrical body of the single crystal is pulled by the shaft (8) which also lifts the members(1, 9).