Semiconductor device and method for fabricating the same
A semiconductor device comprises a lower structure; a plurality of semiconductor layers laterally oriented in a direction parallel to a surface of the lower structure; a plurality of bit lines connected an end of the semiconductor layers and extending in a direction perpendicular to the surface of the lower structure; word lines extending laterally in a direction crossing the semiconductor layers over the semiconductor layers; and a device isolation layer extending in the direction parallel to the surface of the lower structure to be disposed between the bit lines and the word lines and including air gaps.
1 . A semiconductor device comprising:
a lower structure;
a plurality of semiconductor layers laterally oriented in a direction parallel to a surface of the lower structure;
a plurality of bit lines connected to an end of the semiconductor layers and extending in a direction perpendicular to the surface of the lower structure;
word lines extending laterally in a direction crossing the semiconductor layers over the semiconductor layers; and
a device isolation layer extending in the direction parallel to the surface of the lower structure to be disposed between the bit lines and the word lines and including air gaps;
wherein the device isolation layer further includes a capping layer capping an upper portion of the air gaps, wherein the air gaps directly contact a sidewall of the word lines.
2 . The semiconductor device of claim 1 ,
wherein the device isolation layer includes silicon oxide, silicon carbon oxide, silicon nitride, or a combination thereof.
3 . A semiconductor device comprising:
a lower structure;
a plurality of active layers extending in a direction parallel to a surface of the lower structure;
word lines extending laterally in a direction crossing the active layers over the active layers;
a plurality of bit lines connected to an end of the active layers and extending in a direction perpendicular to the surface of the lower structure;
a plurality of capacitors connected to an opposite end of the active layers; and
a device isolation layer including air gaps, the air gaps being disposed between the bit lines and the word lines;
wherein the device isolation layer further includes a capping layer capping an upper portion of the air gaps;
wherein the air gaps directly contact a sidewall of the word lines.
4 . The semiconductor device of claim 3 , wherein the device isolation layer includes silicon oxide, silicon carbon oxide, silicon nitride, or a combination thereof.
5 . The semiconductor device of claim 3 , wherein the air gaps extend vertically from the lower structure.
6 . The semiconductor device of claim 3 , wherein each of the word lines includes a double word line.
7 . The semiconductor device of claim 3 , wherein each of the active layers includes a silicon layer, a monocrystalline silicon layer, a polysilicon layer, or an oxide semiconductor material.