Patent ID: 9530670
Filing Date: 2016-12-27
CPC Classification: C09K,C23F,H01L

Claim Text:
1. A method of forming a conductive pattern, comprising: forming a first conductive layer and a second conductive layer on a substrate, the first conductive layer including a metal nitride having a first metal and the second conductive layer including a second metal, wherein the first metal is different than the second metal, and wherein the metal nitride in the first conductive layer is titanium nitride and the second metal in the second conductive layer is tungsten; etching the first conductive layer and the second conductive layer using an etchant composition that includes phosphoric acid, nitric acid, an assistant oxidant and water, the etchant composition having substantially the same etching rate for the metal nitride and the second metal; and wherein hydrogen peroxide, acetic acid, a hydroxide and fluoric acid are not present in the etchant composition.