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:
Oct. 10, 2017
Filed:
Jun. 02, 2015
Tanaka Kikinzoku Kogyo K.k., Chiyoda-ku, Tokyo, JP;
Hirofumi Nakagawa, Tsukuba, JP;
Tasuku Ishizaka, Tsukuba, JP;
Hirofumi Ishida, Tsukuba, JP;
Akiko Kumakura, Tsukuba, JP;
TANAKA KIKINZOKU KOGYO K.K., Tokyo, JP;
Abstract
An object of the present invention is to provide a purification method to give dodecacarbonyl triruthenium (DCR) which serves as a raw material for chemical vapor deposition and does not cause the contamination of a thin film with impurities even when used to form a ruthenium thin film. The present invention relates to a method in which the dissolved oxygen concentration in the solvent is made 0.2 mg/L or less in at least a dissolution stage, and an organic ruthenium compound including DCR as a raw material for chemical vapor deposition is purified by a recrystallization method. The present invention allows a trace amount of impurities to be separated from DCR. When a ruthenium thin film is formed by use of DCR thus obtained, the formed film is hardly contaminated with impurities. Additionally, the purification method of the present invention is also applicable for recovering/purifying DCR after being used for the formation of a ruthenium thin film.