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:
Sep. 12, 2023
Filed:
Dec. 04, 2019
Globalwafers Japan Co., Ltd., Niigata, JP;
Hiroyuki Saito, Niigata, JP;
GLOBALWAFERS JAPAN CO., LTD., Niigata, JP;
Abstract
Provided is a method for measuring interstitial oxygen concentration in a silicon wafer easily and sensitively using FT-IR. The invention provides a method for measuring an extremely low oxygen concentration of <1.0×10atoms/cmin a single-crystal silicon wafer, the method comprising: step 1 of forming a SiOfilm, nitride film or PE film on each of a measurement wafer, interstitial-oxygen-free reference wafer and standard wafer with known interstitial oxygen concentration; step 2 of measuring IR spectra of the three wafers; step 3 of determining a difference transmission spectrum from the IR spectrum of measurement wafer and that of reference wafer and determining the intensity of an absorption peak corresponding to interstitial oxygen; and step 4 of comparing the peak intensity of the interstitial oxygen and that of standard wafer and calculating the interstitial oxygen concentration in measurement wafer from ratio to the interstitial oxygen concentration of standard wafer.