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:
Jan. 19, 1988
Filed:
Nov. 18, 1986
Karl-Albert Schulke, Grosskrotzenburg, DE;
Heraeus Quarzschmelze GmbH, Hanau, DE;
Abstract
A double-walled quartz-glass tube for semiconductor-technology processes. The overall structure comprises an inner tube surrounded by a coaxially positioned outer tube. An annular space is left between them. The ends of the tubes that face in the same direction each have a closure. A processing-gas supply connection is mounted on the inner-tube closure and extends tight through the outer-tube closure. The outer tube is sealed tight at the other end against the outside of the inner tube. The outer tube has connections for supplying and removing a scrubbing gas. The object is to prevent the occurrence of defects due to differences in the extent that the two tubes expand to as the result of the heat generated during processing. The inner tube has a diameter of at least 150 mm. At least one of the closures is essentially flat. The axis of the processing-gas supply connection is in alignment with the axis of the inner tube. At least the section of the processing-gas supply connection that extends between the two closures has an inside diameter that is 20 to 70% as long as the inside diameter of the inner tube. The outer tube is fused gas-tight to both the processing-gas supply connection and the outside of the inner tube.