SEMICONDUCTOR SUBSTRATE ETCHING METHOD AND SEMICONDUCTOR ELEMENT MANUFACTURING METHOD

摘要

PROBLEM TO BE SOLVED: To provide an etching method which can achieve at the time of etching a first layer containing titanium nitride (TiN), a uniform surface after etching of the TiN-containing layer and a metal layer; and provide an etchant used for the etching method; and provide a semiconductor element manufacturing method using the etching method.SOLUTION: An etching method comprises: selecting a substrate having a surface oxygen content rate of 0.1-10 mol% in a first layer containing titanium nitride (TiN) at the time of processing the substrate having the first layer and a second layer containing transition metal; and removing the first layer by bringing an etchant of pH 7-14 which contains an ammonia compound and an oxidant into contact with the substrate.