ETCHING OF MULTILAYER ELECTRICALLY CONDUCTIVE FILM

摘要

PROBLEM TO BE SOLVED: To provide a method for etching a multilayer electrically conductive film capable of uniformly etching the whole body of a multilayer electrically conductive film coposed of a silver series thin film and a transparent oxide thin film essentially consisting of indium oxide, suppressing residues and side etches and improving the pattern precision thereof. SOLUTION: At the time of subjecting a multilayer electrically conductive film 5 composed by laminating a silver series thin film 3 and transparent oxide thin films 2 and 4 essentially consisting of indium oxide to etching with an etchant essentially consisting of sulfuric acid and nitrid acid, the etching is executed by using an etchant contg. a buffer for suppressing the volatilization of nitric acid.