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:
May. 01, 1979
Filed:
Oct. 19, 1977
Applicant:
Inventors:
Toshiki Kadota, Kodaira, JP;
Toshiro Ono, Tokorozawa, JP;
Katsumi Suzuki, Tokyo, JP;
Yasuo Iida, Tokyo, JP;
Assignees:
Nippon Telegraph & Telephone Public Corporation, Tokyo, JP;
Nippon Electric Co., Ltd., Tokyo, JP;
Primary Examiner:
Int. Cl.
CPC ...
G03B / ;
U.S. Cl.
CPC ...
250505 ; 250320 ; 2504 / ;
Abstract
An x-ray lithography mask including a thick silicon peripheral rib with a window formed therein and a multi-layered membrane transparent to x-rays and visible light supported by the rib and covering the window. The membrane consists essentially of at least two silicon nitride layers and at least one silicon oxide layer sandwiched between the silicon nitride layers. The silicon nitride layers are preferably positioned at opposite surfaces of the multi-layered membrane.