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:
Jun. 02, 1998
Filed:
Aug. 16, 1996
Shoji Kano, Gunma-ken, JP;
Nobuo Kawada, Gunma-ken, JP;
Ryoji Nakajima, Gunma-ken, JP;
Yukio Kurosawa, Gunma-ken, JP;
Shin-Etsu Chemical Co., Ltd., Tokyo, JP;
Abstract
Proposed is an improvement in a vessel, e.g., crucible, of pyrolytic boron nitride (PBN) used, for example, in the process of molecular beam epitaxy for melting silicon and the like at a high temperature. Different from conventional PBN crucibles used for such a process, in which contamination of high-purity silicon is unavoidable by the reaction of molten silicon with PBN or a thermal decomposition products of boron nitride, the inventive PBN vessel is provided on the surface with a protective coating layer of pyrolytic graphite or a refractory metal such as platinum so as not to cause troubles due to contamination of high-purity silicon melted therein with the crucible materials.