Semiconductor device manufacturing method and semiconductor device

Abstract

A semiconductor device manufacturing method includes: forming an element isolation insulating film in a semiconductor substrate; forming a first film on a surface of the semiconductor substrate; forming a second film on the element isolation insulating film and on the first film; forming a first resist pattern that includes a first open above the element isolation insulating film in a first region; removing the second film on the element isolation insulating film in the first region to separate the second film in the first region into a plurality of parts by performing first etching; forming a third film on the second film in the first region; forming a first gate electrode on the third film in the first region; and forming a first insulating film that includes the first to third films under the first gate electrode by patterning the first to third films.

What is claimed is: 
     
         1 . A semiconductor device comprising:
 a semiconductor substrate;   an element isolation insulating film formed in the semiconductor substrate;   a first transistor that includes
 a first insulating film that includes a first film formed on the semiconductor substrate, a second film formed on the first film, and a third film formed on the second film and 
 a first gate electrode formed on the element isolation insulating film and on the first insulating film; 
   a second transistor that includes
 a second insulating film that includes the first film formed on the semiconductor substrate, the second film formed on the first film, and the third film formed on the second film and
 a second gate electrode formed on the element isolation insulating film and on the second insulating film; and 
 
   a third transistor that includes
 a third insulating film formed on the semiconductor substrate and 
 a third gate electrode formed on the element isolation insulating film and on the third insulating film, 
   wherein the second transistor is located adjacent to the first transistor,   the first insulating film is separate from the second insulating film, and   the first gate electrode is connected to the second gate electrode.   
     
     
         2 . The semiconductor device according to  claim 1 , wherein the first gate electrode and the second gate electrode include the same layer.