Semiconductor device and method of fabricating the same

A method for fabricating a semiconductor device, the method comprising:

• forming a storage node contact plug that penetrates an interlayer insulation layer;
• forming a separation insulation layer over the interlayer insulation layer;
• performing a main etch process to form an open region by selectively etching the separation insulation layer, the open region exposing a top surface of the storage node contact plug;
• performing an over-etch process to expand the open region by etching the storage node contact plug by a predetermined thickness at a bottom of the open region;
• forming a storage node in the open region;
• and
• removing the separation insulation layer.

A method for fabricating a capacitor of a semiconductor device, the method comprising:

• forming a first interlayer insulation layer including a first storage node contact plug;
• partially protruding the first storage node contact plug above the first interlayer insulation layer by recessing the first interlayer insulation layer;
• forming a second interlayer insulation layer over the first interlayer insulation layer to cover the protruding first storage node contact plug;
• forming a contact hole to expose the first storage node contact plug by selectively etching the second interlayer insulation layer;
• forming a second storage node contact plug by filling the contact hole with a conductive layer;
• forming a separation insulation layer over the second interlayer insulation layer including the second storage node contact plug;
• forming an open region by selectively etching the separation insulation layer and the second storage node contact plug;
• forming a storage node in the open region;
• and
• removing the separation insulation layer.