METHOD FOR ETCHING A MULTI-LAYERED METAL FILM AND ETCHANT

摘要

Disclosed is a method to etch a multi-layered metal film. The method to etch a multi-layered metal film etches a multi-layered metal film including a first layer formed by a material including one or more among Cu and a Cu alloy and a second layer formed by a material including one or more among Ti and a Ti alloy. The method comprises the steps of: forming a photo-resist film including a predetermined pattern on the multi-layered metal film; etching the multi-layered film by using etchant; and removing the photo-resist film. The etchant in the step of etching the multi-layered metal film comprises one or more from ammonium sulfite and hydroxylammonium sulfate.