Integrated circuit device having an air gap between interconnects and method for manufacturing the same

An integrated circuit device, comprising:

• a substrate;
• a first insulating film provided on the substrate;
• a plurality of vias provided in the first insulating film and extending in a vertical direction;
• a second insulating film provided on the first insulating film, and having a composition different from a composition of the first insulating film;
• and
• a plurality of interconnects extending in a first direction crossing the vertical direction, one of the plurality of interconnects being connected to one of the plurality of vias and the one of the plurality of interconnects having a lower portion disposed in the first insulating film, and an upper portion of the one of the plurality of interconnects disposed in the second insulating film, wherein
• an air gap is formed in the first insulating film and in the second insulating film, and also between two of the plurality of interconnects adjacent to each other, and a lower end of the air gap is located lower than lower surfaces of the two of plurality of interconnects, and
• top surfaces of the plurality of vias are in contact with the second insulating film and are located lower than top surfaces on upper portions of the plurality of interconnects, the upper portions of the plurality of interconnects including the upper portion of the one of the plurality of interconnects.