Patent ID: 6524948
Filing Date: 2003-02-25
Classification: H01L

Abstract:
A method for fabricating a semiconductor device, the method comprising the steps of:depositing a first conductive film on a semiconductor substrate; forming a lower interlayer insulating film on the first conductive film and then selectively etching the lower interlayer insulating film to form a first opening reaching the first conductive film; burying a second conductive film in the first opening to form a lower plug connected to the first conductive film; forming a mask pattern on the lower interlayer insulating film and sequentially etching the lower interlayer insulating film and the first conductive film by using the mask pattern and the lower plug as a mask to form a lower-layer wire composed of the first conductive film and connected to the lower plug; forming an upper interlayer insulating film on the semiconductor substrate such that an air gap is formed in a wire-to-wire space of the lower-layer wire; selectively etching the upper interlayer insulating film to form a second opening reaching the lower plug; burying a third conductive film in the second opening to form an upper plug connected to the lower plug; and forming an upper-layer wire on the upper interlayer insulating film such that the upper-layer wire is connected to the upper plug.