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:
Jul. 14, 2020
Filed:
Apr. 07, 2016
Screen Holdings Co., Ltd., Kyoto, JP;
Ayumi Higuchi, Kyoto, JP;
SCREEN Holdings Co., Ltd., Kyoto, JP;
Abstract
A substrate treatment unit applies surface treatment to a semiconductor substrate by using a chemical solution. The chemical solution in which metal is dissolved by substrate treatment is discharged into a storage tank and stored. A polyacid supplying unit supplies polyacid of a deletion complex with a deficient portion into the storage tank. The polyacid of deletion complex with a deficient portion is mixed into a used chemical solution containing the metal, and a pH value of the mixed solution is adjusted to between 2 and 3 to capture the metal dissolved in the chemical solution in the deficient portion of the polyacid. In addition, a counter cation is put into the chemical solution so that the polyacid in which the metal is captured is precipitated to be separated from the chemical solution, and thus the metal contained in the chemical solution during the treatment of the semiconductor substrate can be removed to enable the chemical solution to be reclaimed.