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:
Apr. 21, 2015
Filed:
Jan. 17, 2012
Masahiro Takahata, Ibaraki, JP;
Kazuyuki Satoh, Ibaraki, JP;
Satoyasu Narita, Ibaraki, JP;
Takeshi Gohara, Ibaraki, JP;
Masahiro Takahata, Ibaraki, JP;
Kazuyuki Satoh, Ibaraki, JP;
Satoyasu Narita, Ibaraki, JP;
Takeshi Gohara, Ibaraki, JP;
JX Nippon Mining & Metals Corporation, Tokyo, JP;
Abstract
The present invention addresses the problem of providing a technique capable of efficiently and stably providing a method for producing high-purity lanthanum, the method characterized in that: a crude lanthanum oxide starting material having a purity of 2N-3N, excluding gas components, is used; the material is subjected to molten salt electrolysis at a bath temperature of 450-700° C. to produce lanthanum crystals; the lanthanum crystals are subsequently desalted: and electron beam melting is then performed to remove volatile substances. The present invention also addresses the problem of providing a technique capable of efficiently and stably providing high-purity lanthanum, high-purity lanthanum itself, a sputtering target formed from high-purity material lanthanum; and a thin film for metal gates that has high purity lanthanum as the main component.