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:
Nov. 03, 2020
Filed:
Aug. 17, 2017
Sumco Corporation, Tokyo, JP;
Hiroshi Kishi, Akita, JP;
Masanori Fukui, Akita, JP;
SUMCO CORPORATION, Tokyo, JP;
Abstract
In an exemplary embodiment, a quartz glass crucibleincludes: a high-aluminum-content layerB which is made of quartz glass having a relatively high average aluminum concentration and is provided to form an outer surfaceof the quartz glass crucible; and a low-aluminum-content layerA which is made of quartz glass having a lower average aluminum concentration than that of the high-aluminum-content layerB and is provided on an inner side of the high-aluminum-content layerB, wherein the low-aluminum-content layerA includes an opaque layermade of quartz glass containing a large number of minute bubbles, and the high-aluminum-content layerB is made of transparent or translucent quartz glass having a lower bubble content than that of the opaque layer. The quartz glass crucible is capable of withstanding a single crystal pull-up step undertaken for a very long period of time.