Semiconductor device and method of manufacturing the same

A method of manufacturing a semiconductor device, the method comprising:

• forming, in a first direction, trenches in isolation regions of a semiconductor substrate;
• forming an isolation layer in each of the of trenches;
• forming gate lines, in a second direction crossing the first direction, over the isolation layers and over active regions defined between the isolation layers;
• forming first air gaps, extending in the first direction, by performing an etching process to remove at least a portion of each of the isolation layers;
• and
• forming an insulating layer between the gate lines so that an air gap is formed in the insulating layer, wherein the air gap extends in the first direction in the trenches and extends in the second direction between the gate lines.

A semiconductor device, comprising:

• a semiconductor substrate having trenches defined, in a first direction, by corresponding isolation regions;
• a plurality of gate lines formed on the semiconductor substrate, the gate lines being defined, in a second direction crossing the plurality of trenches, by an insulating layer;
• first air gaps formed in, and defined by, each of the trenches;
• and
• second air gaps formed in, and defined by, the insulating layer.