ETCHANT, ETCHING METHOD USING THE SAME AND MANUFACTURING METHOD OF SEMICONDUCTOR ELEMENT

摘要

PROBLEM TO BE SOLVED: To provide an etchant selectively and effectively removing a first layer containing TiN from a second layer containing specific metals, an etching method using the same and a manufacturing method of a semiconductor element.SOLUTION: An etchant removes a first layer selectively by treating a base plate having the first layer containing TiN and a second layer containing at least one metal selected from transition metals in group 3 to group 11, and contains a hexafluorosilicic acid compound and an oxidant of 0.05 mass% or more and less than 10 mass%.