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. 05, 2011
Filed:
May. 14, 2009
Yoshihiro Kubota, Gunma, JP;
Shoji Akiyama, Gunma, JP;
Toshihiko Shindo, Gunma, JP;
Shin-Etsu Chemical Co., Ltd., Tokyo, JP;
Abstract
A pellicle film of a silicon single crystal film and a base substrate supporting the pellicle film are formed of a single substrate using an SOI substrate. The base substrate is provided with an opening whose ratio in area to an exposure region when a pellicle is used on a photomask (an open area ratio) is 60% or more, and provided with a reinforcing frame in a non-exposure region of the base substrate. Since the pellicle film and the base substrate supporting the pellicle film are formed of the single substrate (an integrated structure), and the base substrate is provided with the reinforcing frame, the effect of increased strength is obtained. Moreover, a principal plane of a silicon single crystal film is a crystal plane inclined at 3 to 5° from any lattice plane belonging to {100} planes or {111} planes.