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:
Sep. 21, 1993
Filed:
Jan. 31, 1991
Joseph C Liu, Bloomington, MN (US);
Seagate Technology, Inc., Scotts Valley, CA (US);
Abstract
A formation process has a plurality of process steps performed according to a set of process parameters. The formation process is used to form substrates in magnetic discs. A displacement signal is obtained which is representative of surface displacement of the substrate after at least one of the process steps. A first spectral signature is determined based on the displacement signal. The first spectral signature has characteristics representative of the surface displacement of the substrate when processed according to a first set of process parameters. The first spectral signature is compared with a second spectral signature having characteristics indicative of surface displacement of a substrate when processed according to a second set of process parameters. Based on the comparison, the set of process parameters is identified which provides a spectral signature closest to a desired spectral signature.