Etching solutions for copper and copper alloys and etching process using the same
AssigneeTokai Denka Kogyo Kabushiki Kaisha
InventorsAkira Matsumoto, Katsutoshi Itani
Life of this patent
Estimating the term…
Abstract
This invention provides etching solutions for copper and copper alloys comprising a mixed aqueous solution of a peroxysulfate with a purine compound and a halogen compound added as the catalyst. There is also provided a process for etching copper or copper alloys with said etching solutions.
Claims9
An etching solution for copper and copper alloys comprising an aqueous peroxysulfate solution containing from 5 percent by weight to its solubility limit therein of a peroxysulfate, from 10 parts per million to its solubility limit therein of a purine compound, and from 5 parts per million to 1,000 parts per million of a halogen compound which liberates halogen in an aqueous peroxysulfate solution.
An etching solution for copper and copper alloys comprising an aqueous solution containing from 5 percent by weight to its solubility limit therein of a peroxysulfate, from 10 parts per million to its solubility limit therein of a purine compound, and from 5 parts per million to 1,000 parts per million of a halogen compound which liberates halogen in an aqueous peroxysulfate solution.
In the process for etching copper and copper alloys with an aqueous peroxysulfate solution containing from 5 percent by weight to its solubility limit therein of a peroxysulfate, which comprises adding to said solution from 10 parts per million to its solubility limit therein of a purine compound, and from 5 parts per million to 1,000 parts per million of a halogen compound which liberates halogen in an aqueous peroxysulfate solution.
Dependencies are inferred from the claim text.