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. 17, 2001
Filed:
May. 20, 1999
Applicant:
Inventors:
Hidehiro Kanazawa, Tokyo, JP;
Minoru Otani, Tokyo, JP;
Kenji Ando, Kawasaki, JP;
Yasuyuki Suzuki, Yokohama, JP;
Ryuji Biro, Kawasaki, JP;
Assignee:
Canon Kabushiki Kaisha, Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C23C 1/434 ;
U.S. Cl.
CPC ...
C23C 1/434 ;
Abstract
A process is provided for forming a thin film having refractive index thereof varying continuously or stepwise in a thickness direction. The process comprises sputtering in a vacuum chamber by introducing, during film formation, at least two kinds of gases selected from a nitrogen-containing gas, an oxygen-containing gas, and a fluorine-containing gas with the flow rate ratio of the gases varied continuously or stepwise. This process enables variation of the refractive index in the thickness direction, simply without difficulty.