Abstract: A method for fabricating a semiconductor device includes providing a substrate including a cell region including a bit line structure, a bit line spacer and a lower electrode and a peripheral circuit region including first to third impurity regions, forming an interlayer insulating film on the peripheral circuit region, forming a first metal layer on the interlayer insulating film, forming a first trench and a second trench in the first metal layer between the first and second impurity regions, the second trench is disposed between the second and third impurity regions and exposes the interlayer insulating film, forming a first capping pattern on the first trench to form an air gap in the first trench, filling the second trench with a first insulating material, and forming, on the first metal layer, a contact connected to the third impurity region.

Abstract: A method for fabricating a semiconductor device includes providing a substrate including a cell region including a bit line structure, a bit line spacer and a lower electrode and a peripheral circuit region including first to third impurity regions, forming an interlayer insulating film on the peripheral circuit region, forming a first metal layer on the interlayer insulating film, forming a first trench and a second trench in the first metal layer between the first and second impurity regions, the second trench is disposed between the second and third impurity regions and exposes the interlayer insulating film, forming a first capping pattern on the first trench to form an air gap in the first trench, filling the second trench with a first insulating material, and forming, on the first metal layer, a contact connected to the third impurity region.