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:
Sep. 14, 1993
Filed:
Sep. 30, 1991
Yasushi Hashizume, Itami, JP;
Mitsuhiro Tomikawa, Itami, JP;
Mitsubishi Denki Kabushiki Kaisha, Tokyo, JP;
Abstract
A semiconductor device manufacturing apparatus has a heat retaining tube which can be freely placed in and pulled out of a processing chamber of the apparatus. When located within the processing chamber, the heat retaining tube surrounds a boat with the semiconductor wafers mounted thereon. After the thermal processing of the semiconductor wafers has been completed, the heat retaining tube and the semiconductor wafers are pulled out of the processing chamber together. In this way, the difference in the temperature of the center and periphery of the semiconductor wafer is decreased, and semiconductor devices, which have excellent performance and which are free from crystalline defects or dislocation, can thus be manufactured.