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:
Mar. 19, 2019
Filed:
Sep. 25, 2017
Sumitomo Electric Industries, Ltd., Chuo-ku, Osaka-shi, JP;
Yukihiro Tsuji, Tama, JP;
SUMITOMO ELECTRIC INDUSTRIES, LTD., Osaka, JP;
Abstract
A method for producing a semiconductor device includes the steps of: providing a substrate product including a substrate and a first stacked semiconductor layer disposed on the substrate, the first stacked semiconductor layer including a plurality of semiconductor layers having different compositions that are alternately and periodically stacked with a predetermined period; forming a mask on the substrate product; and etching the first stacked semiconductor layer using the mask. The step of etching the first stacked semiconductor layer includes the steps of: optically monitoring an optical signal including a light component reflected from an etched surface of the substrate product for detecting an endpoint of etching; converting the optical signal to an electric signal to generate a monitoring signal; performing Fourier transform on the monitoring signal to generate a spectrum signal; and determining the endpoint detection of the etching by using the spectrum signal provided by the Fourier transform.