Wet cleaning stripping of etch residue after trench and via opening formation in dual damascene process

Abstract

After trench line pattern openings and via pattern openings are formed in a inter-metal dielectric insulation layer of a semiconductor wafer using trench-first dual damascene process, the wafer is wet cleaned in a single step wet clean process using a novel wet clean solvent composition. The wet clean solvent effectively cleans the dry etch residue from the plasma etching of the dual damascene openings, etches back the TiN hard mask layer along the dual damascene openings and forms a recessed surface at the conductor metal from layer below exposed at the bottom of the via openings of the dual damascene openings.