US Patent 8466055 Semiconductor device and method of manufacturing semiconductor device

A method of manufacturing a semiconductor device includes forming a first insulating layer, forming a trench in the first insulating layer, forming an interconnect in the trench, forming a space between the first insulating layer and the interconnect, and disposing an upper surface of the interconnect at a position higher than an upper surface of the first insulating layer, forming an air gap in the space and forming an etching stopper film over the first insulating layer and the interconnect, forming a second insulating layer over the etching stopper film, and forming a via in the second insulating layer to be disposed over the interconnect.