Semiconductor device and method for fabricating the same

A semiconductor device comprising:

• a substrate including a first active region;
• a first bit line on the first active region;
• a first spacer extending along at least a portion of a side surface of the first bit line, the first spacer including SiOC in contact with the first bit line;
• and
• a second spacer on the first spacer, the second spacer including silicon nitride.

A semiconductor device comprising:

• a substrate;
• a bit line on the substrate, the bit line extending in a first direction;
• a word line in the substrate, the word line extending in a second direction intersecting the first direction;
• a capping pattern on the word line, the capping pattern extending in the second direction, and the capping pattern having therein a first portion of a trench;
• a first spacer including a silicon oxide film lining the first portion of the trench;
• and
• a second spacer on the first spacer, the second spacer disposed in a region of the first portion of the trench left unfilled by the first spacer.