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:
Oct. 24, 2000
Filed:
Apr. 14, 1999
Takashi Masuyuki, Tokyo, JP;
Katsuaki Ishimaru, Kawasaki, JP;
Nikon Corporation, Tokyo, JP;
Abstract
When a relatively thin substrate, such as a silicon wafer, is used in an exposure apparatus, a substrate adjuster is inserted between the thin substrate and the substrate holder in order to raise the position of the top surface of the thin wafer. The substrate adjuster is selected so that the sum of the thicknesses of the substrate adjuster and the thin substrate lies within the range of thicknesses of ordinarily used substrates. If a relatively thick substrate, for example, a ceramic substrate, is used, the substrate is directly held on the substrate holder without using the substrate adjuster. The substrate holder holds the substrate adjuster through vacuum adsorption, which also helps the substrate be adsorbed onto the substrate adjuster. In this manner, different substrates having different thicknesses can be used in the exposure apparatus without exchanging the substrate holder.