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:
May. 21, 1991
Filed:
Aug. 17, 1989
Katsuhiko Iwabuchi, Sagamihara, JP;
Osamu Yokokawa, Sagamihara, JP;
Eiichiro Takanabe, Shiroyama, JP;
Tel Sagami Limited, Kanagawa, JP;
Abstract
A heat treatment apparatus used in the manufacturing of semiconductor devices and the like, for treating with a reaction gas substrates placed in a reaction tube of the apparatus. A support table is provided within the reaction tube, for supporting substrates during a treatment process, and is rotated during each treatment by a motor, via a shaft penetrating the reaction tube. That portion of the reaction tube which is penetrated by the shaft is provided with a journal bearing and a magnetic fluid seal member. The seal member is surrounded by an enclosing space which substantially separates the seal member from the reaction space within the reaction tube, the enclosing space and the reaction space communicating with each other via a narrow passage. During a heat treatment, a shield gas is supplied into the enclosing space, the pressure within the enclosing space being maintained at a higher level than that within the reaction space. As a result, the reaction gas and a gas produced during heat treatment cannot come into contact with the seal member, and thus cannot adversely affect the seal member.