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:
Nov. 11, 1997
Filed:
Jul. 09, 1996
Masahiko Kokubo, Kyoto, JP;
Masahiro Horie, Kyoto, JP;
Abstract
A film thickness measuring apparatus measures the thickness of a thin film which is formed on a substrate with an excellent reproducibility regardless of inclination of a surface of a sample. Since an illumination system (20) includes a glass rod (GL) which corrects wavelength dependencies of luminance distributions of light sources (HL, DL), even when an eclipse in reflected light due to inclination of a sample (SP) decreases the energy of the reflected light, a spectral distribution of the reflected light entering a spectroscopic unit (40) is maintained with almost no change. A control unit (50) performs data conversion of multiplying an actual spectral reflectance by a ratio of an average of the actual spectral reflectance which is determined based on an output from the spectroscopic unit (40) to an average of a calibrated spectral reflectance and thereafter calculates a deviation between the two spectral reflectances. As a result, the film thickness is accurately measured while preventing an influence of inclination of the sample (SP).