Patent ID: 9058975
Filing Date: 2015-06-16
Classification: C09K,C11D,H01L

Abstract:
1. An aqueous cleaning solution for removing metal contaminants from a dielectric structure with electrolessly deposited cobalt or cobalt alloy caps after electrolessly depositing the cobalt or cobalt alloy caps over metal lines in the dielectric structure, comprising: a pH adjustor; a complexing agent comprising phytic acid; a corrosion inhibitor capable so as to protect electrolessly deposited cobalt or cobalt alloy caps on metal lines over the dielectric structure; and one or more of: wherein the aqueous cleaning solution is capable so as to remove metal ions from the dielectric structure, wherein: the pH adjustor has a concentration of less than 0.1 M and includes at least one of a sulphuric acid, sulfonic acid, methanesulfonic acid, benzene sulfonic acid, triflic acid, hypophosphorous acid, oxalic acid, halogenated carboxylic acids, trifluoroacetic acid, acetylenedicarboxylic acid, squaric acid, dihydroxyfumaric acid, maleic acid, or mixtures thereof; the complexing agent has a concentration from 0.1 to 200 mM; the corrosion inhibitor has a concentration from 0.1 to 50 mM and comprises at least one of a triazole, benzotriazole, methyl-benzotriazole, 5-methyl-benzotriazole, carboxy-benzotriazole, hydroxybenzotriazole, mercaptobenzothiazole, polyvinylpyrrolidone, polyvinylalcohol, polyamine, polyimine, polyalkylimine, polyethylenimine, long chain alkylamine, tetrazole, phosphate, inorganic phosphate, alkylphosphate, metaphosphate, phosphite, phosphonate, fluoroalkylphosphate, silicate, alkylphosphonate, fluoroalkylphosphonate, alkoxysilane, nitrite, bicyclohexylammonium nitrite, or combinations thereof; the solubilizing agent is present at a concentration less than 200 mL/L and comprises one or more of a primary alcohol, secondary alcohol, tertiary alcohol, polyol, ethylene glycol, propylene glycol, 2-n-butoxyethanol, dimethylsulfoxide, propylenecarbonate, or combinations thereof; the dielectric etchant is present at a concentration from 1 to 100 mM and comprises one or more of a hydrogen fluoride, hydrogen tetrafluoroborate, hydrogen hexafluorosilicate, non-alkali metal alt of fluoride, tetrafluoroborate, hexafluorosilicate, or mixtures thereof; the surfactant is present at a concentration of less than 2000 ppm and comprises at least one of anionic surfactants, cationic surfactants, nonionic surfactants, amphoteric surfactants, or combinations thereof; and the aqueous cleaning solution has a pH less than or equal to 3.