Patent ID: 9688912
Date: 2017-06-27
CPC Classifications: C09K,H01L

Claim:
1. An etching liquid for selective etching of a first layer containing Ti with regard to a second layer containing Cu, the etching liquid comprising, in an aqueous medium, a basic compound composed of an organic amine compound, a water soluble organic solvent and an oxidizing agent, the etching liquid having a pH of 9 or more, wherein the basic compound composed of an organic amine compound is selected from the group consisting of tetramthylammonium hydroxide, tetraethylammonium hydroxide and tetrapropylammonium hydroxide, the water soluble organic solvent is selected from the group consisting of propylenglycol, ethylenglycol and dipropylenglycol, the oxidizing agent is selcted from the group consisting of hydrogen peroxide and peracetic acid, and the basic compound is present in an amount of 1 to 10% by mass, the organic solvent is present in an amount of 5 to 50% by mass, and the oxidizing agent is present in an amount of 0.5 to 10% by mass, with respect to the total amount of the etching liquid.