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:
Jan. 26, 1999
Filed:
Sep. 21, 1995
Kenji Nakagawa, Kawasaki, JP;
Katsuyoshi Kobayashi, Kawasaki, JP;
Fujitsu Limited, Kanagawa, JP;
Abstract
A pattern forming method includes the steps of preparing an underlie layer having a surface to be processed; coating a resist film on the underlie layer, the resist film including a substance capable ot absorbing light applied during exposure, thereby capable of attenuating light reflected from the surface of said underlie layer during the exposure, in comparison to a resist film not containing the substance; and transferring a pattern of a photomask onto the resist by using a modified illumination system, the photomask, and a projecting lens, the modified illumination system radiating principal light from the direction offset from an optical axis of a condenser lens. Exposure is performed by relieving the influence of light reflection from an underlie layer surface by using resists whose transmittance have been adjusted, and by using a stepper with a modified illumination system. A sufficient depth of focus is obtained and the resolution of the resist is substantially improved. A resist pattern of a good shape can be obtained by relieving the influence of light reflection from the underlie layer surface.