Method for fabricating storage node contact in semiconductor device

A method for fabricating a plurality of storage node contacts in a semiconductor device, comprising the steps of:

• forming a first inter-layer insulation layer on a substrate;
• forming a plurality of bit line patterns including a hard mask nitride layer on the inter-layer insulation layer;
• forming a plurality of nitride based bit line spacers in contact with both lateral sides of the plurality of bit line patterns;
• forming second inter-layer insulation layer filling gaps between the plurality of bit line patterns;
• planarizing the second inter-layer insulation layer by performing a first chemical mechanical polishing process to the second inter-layer insulation layer two times until the polishing is stopped on surfaces of the plurality of bit line patterns;
• forming a plurality of storage node contact holes opening a substrate of the substrate between the plurality of bit line patterns by selectively etching the first and the second inter-layer insulation layers;
• forming a conductive layer filling the plurality of storage node contact holes;
• forming a plurality of storage node contacts by performing an etch back to the conductive layer;
• and
• additionally performing a second chemical mechanical polishing process to the second inter-layer insulation layer to remove the plurality of cruspidal patterns generated during performing the etch back to the conductive layer by using a slurry having a polishing speed faster than a polishing speed of surrounding materials of the cruspidal patterns.