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. 05, 2025
Filed:
Sep. 17, 2020
Hitachi High-tech Corporation, Tokyo, JP;
Mitsuru Nagasawa, Tokyo, JP;
Soichiro Eto, Tokyo, JP;
Tatehito Usui, Tokyo, JP;
Shigeru Nakamoto, Tokyo, JP;
Hitachi High-Tech Corporation, Tokyo, JP;
Abstract
A process of detecting a thickness of a film layer to be processed or a depth of etching by using a result of detection of a signal indicating intensity of interference light having a plurality of wavelengths formed by being reflected on a surface of a wafer at a plurality of time instants from when plasma is formed to when the etching is completed. A start time instant is detected by using an amount of change in the intensity of the interference light. Then, a remaining film thickness or the etching amount at an arbitrary time instant is detected from a result of comparing actual data indicating the intensity of the interference light at the arbitrary time instant during the processing after the start time instant with a plurality of pieces of data for detection of the intensity of the interference light obtained in advance and associated with values of the film thicknesses or the depths of etching.