Method for manufacturing a semiconductor device

Abstract

A semiconductor device 100 includes a first gate 210 , which is formed using a gate last process. The first gate 210 includes a gate insulating film formed in a bottom surface in a first concave portion formed in the insulating film; a gate electrode formed over the gate insulating film in the first concave portion; and a protective insulating film 140 formed on the gate electrode in the first concave portion. In addition, the semiconductor device 100 includes a contact 134 , which is coupled to the N-type impurity-diffused region 116 a in the both sides of the first gate 210 and is buried in the second concave portion having a diameter that is large than the first concave portion.

1 . A method for manufacturing a semiconductor device, including:
 forming a dummy gate electrode over a semiconductor substrate;   forming a first insulating film covering the dummy gate electrode, over the semiconductor substrate;   planarizing the first insulating film to expose an upper surface of the dummy gate electrode;   removing the dummy gate electrode to form a concave portion;   forming a metallic film over the semiconductor substrate to fill the concave portion with the metallic film;   removing portions of the metallic film exposed outside of the concave portion using a chemical mechanical polishing process to form a gate electrode in the concave portion;   after removing the portions of the metallic film, forming a second insulating film in an upper region of the metallic film to fill the concave portion.   
     
     
         2 . The method for manufacturing a semiconductor device according to  claim 1 , comprising a further step, after forming the second insulating film, of forming a third insulating film over the semiconductor substrate;
 wherein the third insulating film is in contact with the second insulating film.