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:
Jul. 17, 2001
Filed:
Dec. 06, 1999
Cameron J. Brooks, South Burlington, VT (US);
Michael J. Lercel, Williston, VT (US);
Lynn A. Powers, South Burlington, VT (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
A stencil or scatterer mask for use with charged particle beam lithography such as projection electron-beam lithography comprises a membrane layer of a material having a Young's modulus of at least about 400 GPa and support struts supporting a surface of the membrane. The struts form and surrounding a plurality of discrete membrane areas of different aspect ratios aligned to design regions of an integrated circuit. The discrete membrane areas have different aspect ratios range from about 1:1 to about 12:1, and the discrete membrane areas have different size surface areas. The membrane is preferably silicon carbide, diamond, diamond-like carbon, amorphous carbon, carbon nitride or boron nitride. When used in scatterer masks, the ratio of discrete membrane area to membrane thickness is at least about 0.18 mm,/nm. When used in stencil masks, the ratio of discrete membrane area to membrane thickness is at least about 1.0 mm,/nm. The stencil mask is made by depositing a diamond membrane film patterned with a hardmask layer on a substrate, depositing an etch stop layer adjacent the diamond film, and forming supporting struts surrounding a plurality of discrete areas of the membrane film. The method then includes depositing a pattern over the membrane film within the discrete membrane film areas, the pattern conforming to one or more desired circuit elements, and etching the membrane film with a reactive ion etch containing oxygen to form openings in the membrane film.