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. 30, 1984
Filed:
Feb. 14, 1984
Applicant:
Inventors:
Assignee:
Hitachi, Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H01L / ; B44C / ; C03C / ; C23F / ;
U.S. Cl.
CPC ...
156626 ; 156643 ; 156345 ; 356445 ;
Abstract
The present invention consists in an etching method and apparatus wherein an optical image which is reflected from a region of a dicing stripe pattern on a substrate to-be-etched, such as a semiconductor wafer, is focused by a projecting optical system during selective etching. The focused pattern is converted into an image signal by an image detector, and a change of contrast in the region of the dicing stripe pattern is determined from the image signal. Based on this, an ending time for the etching can be decided from the change of contrast.