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:
Feb. 28, 2012
Filed:
Jun. 06, 2008
Norio Ishikawa, Soka, JP;
Norio Ishikawa, Soka, JP;
Kanto Kagaku Kabushiki Kaisha, Tokyo, JP;
Abstract
As a washing liquid and an etching solution for semiconductor substrates and glass substrates, alkaline aqueous solutions are used; however, since metal impurities are adsorbed on the substrate surface during processing, a next process for removing the adsorbed metal impurities is required. In addition, when a washing liquid is used, it cannot wash off metal impurities; therefore an acid washing process is required. The present invention provides an aqueous solution composition, which is an alkaline aqueous solution but is able to prevent adsorption of metal impurities, which also has cleaning capability. By means of an alkaline aqueous solution composition used for washing or etching a substrate, the composition comprising a chelating agent represented by the general formula (1): and an alkaline component, the adsorption of metal impurities on the substrate is prevented, and metal impurities adsorbed on the substrate are washed off.