Patent ID: 8481432

Claim:
A method of isotropically etching copper-containing portions of a partially fabricated semiconductor substrate containing a region of copper-containing metal, the method comprising: (a) receiving the partially fabricated semiconductor substrate comprising an exposed region of copper-containing metal; and (b) isotropically etching the copper-containing metal on the substrate by a non-CMP (chemical mechanical polishing) method comprising contacting the copper-containing metal on the substrate with an abrasive-free wet etching solution at a pH in a range of between about 5 and 12, wherein the solution comprises (i) at least one bidentate, tridentate, or quadridentate complexing agent for ions of copper, and (ii) an oxidizer, wherein contacting the substrate with the etching solution is selected from the group consisting of spraying the etching solution onto the semiconductor substrate, spin on contact, and contacting the semiconductor substrate with the etching solution in a thin film reactor.