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. 07, 1986
Filed:
Dec. 24, 1984
Applicant:
Inventors:
Assignee:
Hitachi, Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G01B / ;
U.S. Cl.
CPC ...
356378 ; 356446 ; 356355 ;
Abstract
An apparatus for measuring in a non-contact manner the depth of pits and grooves formed by etching in periodic patterns on the surface of a substrate. The measurement is based on the detection of the intensity of a diffraction ray excluding that of the 0th order through the irradiation of a light beam with variable wave length to the sample. Whereas, the conventional measuring system is sensitive to a diffraction ray of the 0th order, i.e., the major component of the reflected light, that hampers the detection of a higher order diffraction ray carrying information of the depth.