Abstract: A method for fabricating memory device includes forming a bit line pattern including a first conductive layer and a hard mask stacked over a substrate, forming a sacrificial layer on sidewalls of the bit line pattern, forming a second conductive layer in contact with the sacrificial layer and adjacent to the bit line pattern, recessing the second conductive layer, forming an air gap between the recessed second conductive layer and the first conductive layer by removing the sacrificial layer, and forming an air gap capping layer on sidewalls of the hard mask to cap entrance of the air gap.