Semiconductor device and method for fabricating the same
A semiconductor device includes a plurality of first conductive patterns separated by a damascene pattern, a second conductive pattern buried in the damascene pattern, and a spacer including an air gap between the second conductive pattern and the first conductive patterns.
1. A semiconductor device, comprising:
a plurality of first conductive patterns separated by a damascene pattern;
a second conductive pattern buried in the damascene pattern; and
a spacer comprising an air gap between the second conductive pattern and the first conductive patterns,
wherein the spacer further comprises a first spacer and a second spacer, and the air gap is disposed between the first spacer and the second spacer,
wherein the first spacer comprises a silicon nitride layer and the second spacer comprises an oxide layer.
2. The semiconductor device of claim 1 , further comprising:
a capping layer configured to hermetically seal an upper portion of the air gap.
3. The semiconductor device of claim 1 , wherein the spacer further comprises a silicon nitride layer.
4. The semiconductor device of claim 1 , wherein the oxide layer comprises a silicon oxide layer or a tungsten oxide layer.
5. The semiconductor device of claim 1 , wherein the first conductive patterns comprise storage node contact plugs, and the second conductive pattern comprises a bit line.
6. The semiconductor device of claim 5 , wherein the storage node contact plugs comprise a polysilicon layer or a tungsten layer.
7. The semiconductor device of claim 1 , wherein the spacer further comprises a bottom surface that extends underneath the second conductive pattern.