Patent ID: 8372757

Claim:
A method of processing a damascene feature on a partially fabricated semiconductor substrate, the method comprising: (a) receiving a semiconductor substrate having a field region and at least one recessed damascene feature formed in the substrate, wherein the substrate is lined with a layer of conductive material; (b) completely electrochemically filling the recessed damascene feature with a copper-containing metal and forming a copper-containing overburden over the field region, wherein the overburden comprises a recess over the filled recessed damascene feature, said recess having substantially the same depth as the overburden thickness; (c) continue electrodepositing copper-containing metal over the substrate to deposit additional overburden material over the field region while substantially reducing the aspect ratio of the recess in the overburden, wherein the thickness of additional overburden material deposited over the field region is at least about 50% of the first thickness of the overburden deposited in (b), wherein (c) only partially fills the recessed feature in the overburden; and (d) wet etching the copper-containing overburden to remove at least all additional overburden deposited in (c) by contacting the substrate with an isotropic wet etching solution, said solution comprising a complexing agent and an oxidizing agent and having a pH in the range of between about 5 and 12, wherein wet etching further reduces the aspect ratio of the recessed feature.