Semiconductor device and method of manufacturing the same

Abstract

An upper surface of a plug (PL1) is formed so as to be higher than an upper surface of an interlayer insulating film (PIL) by forming the interlayer insulating film (PIL) on a semiconductor substrate (1S), completing a CMP method for forming the plug (PL1) inside the interlayer insulating film (PIL), and then, making the upper surface of the interlayer insulating film (PIL) to recede. In this manner, reliability of connection between the plug (PL1) and a wiring (W1) in a vertical direction can be ensured. Also, the wiring (W1) can be formed so as not to be embedded inside the interlayer insulating film (PIL), or a formed amount by the embedding can be reduced.

What is claimed is: 
     
         1 . A semiconductor device comprising:
 a first interlayer insulating film formed on a semiconductor substrate;   a first plug formed inside the first interlayer insulating film;   a second interlayer insulating film formed on the first interlayer insulating film and having a dielectric constant lower than a dielectric constant of silicon oxide; and   a first buried wiring formed inside the second interlayer insulating film and connected to the first plug,   an upper surface of the first plug being formed at a position higher than an upper surface of the first interlayer insulating film, and   a lower surface of the first buried wiring being formed at a position lower than the upper surface of the first plug.