Methods of forming self-aligned contact pads on electrically conductive lines

A method for forming a self aligned contact pad in a semiconductor device comprising:

• forming a plurality of spaced apart gate structures on a semiconductor substrate, wherein each of said gate structures comprises a gate electrode layer, a gate capping layer thereon and a gate sidewall spacer;
• forming an insulating layer over said substrate and on said gate electrode structures to completely fill spaces between said gate electrode structures;
• using a contact pad formation mask and etching said insulting layer to form a plurality of openings exposing simultaneously a plurality of contact regions of said substrate;
• filling said openings with a conductive material that has an etching selectivity with respect to said capping layer;
• etching back said conductive material and said insulating layer until a top surface of said capping layer is exposed and forming a plurality of contact pads to be electrically connected to said corresponding contact regions of said substrate and electrically isolated from each other;
• and
• wherein said etching back is carried out on said capping layer to have an etching selectivity with respect to said conductive material at the end of said etching back process.