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:
Aug. 02, 1994
Filed:
Oct. 07, 1993
NKK Corporation, Tokyo, JP;
Abstract
Movable optical parts included in an ellipsometer are omitted to increase the measurement speed and maintain constant, high measurement precision in film thickness measurement processing. A beam is radiated from a light source section onto a measurement target. A reflected beam having an elliptically polarized beam reflected by the measurement target is divided into four light components polarized in different directions. The optical intensities of the respective polarized light components are detected. Of the four detected optical intensities, one having the minimum value is omitted, and ellipsometric parameters .psi. and .DELTA. are calculated by using the remaining three optical intensities having the largest values. The ellipsometer comprises only stationary optical parts without using any movable optical parts. The polarization directions of the respective polarized light components, from which four optical intensities are obtained, are set at angles of 90.degree., 0.degree., +45.degree., and -45.degree. with respect to a reference direction. A composite beam splitter is used to extract the four polarized light components.