Semiconductor device and method for fabricating the same

Abstract

Insulation films 45, 56 having a contact hole 58 are formed on a substrate. A dummy plug 62 is formed in the contact hole 58. Insulation films 64, 66 are formed on the insulation film 56. An opening 70 for exposing at least a part of the dummy plug 62 is formed in the insulation films 64, 66. The dummy plug 62 is selectively removed through the opening 70. A storage electrode 72 is formed in the contact hole 58 and the opening 70. The insulation film 66 is selectively removed. A dielectric film 74 and a plate electrode are formed on the storage electrode 72. Whereby, without an extra support for supporting the storage electrode 72, the storage electrode 72 is prevented form falling down or peeling off, and defective contact and breakage of the lower structure due to disalignment can be precluded.

What is claimed is:  
     
         1 . A semiconductor device comprising: 
 a first insulation film formed on a substrate, the first insulation film having a contact hole down to the substrate;    a first electrode including a contact part formed in the contact hole, and a projection part connected to only a part of the upper surface of the contact part and projected above the first insulation film, the contact part and the projection part being formed of the same conducting layer;    a dielectric film formed on the first electrode; and    a second electrode formed on the dielectric film and opposed to the first electrode.    
     
     
         2 . A semiconductor device according to  claim 1 , further comprising: 
 a conducting film formed on an inside wall and a bottom of the contact hole, the conducting film being for improving adhesion between the first insulation film and the first electrode or for prohibiting reaction between the substrate and the first electrode.    
     
     
         3 . A semiconductor device according to  claim 2 , wherein 
 the conducting film is formed, extended over the first insulation film.    
     
     
         4 . A semiconductor device according to  claim 2 , wherein 
 the conducting film is formed, extended over the upper surface of the contact part of the first electrode.    
     
     
         5 . A semiconductor device according to  claim 1 , further comprising: 
 a second insulation film formed on the first insulation film interposing the dielectric film therebetween, the second insulation film being formed extended in the contact hole.    
     
     
         6 . A method for fabricating a semiconductor device comprising the steps of: 
 forming on a substrate a first insulation film having a contact hole formed therein;    forming a dummy plug in the contact hole;    forming a second insulation film on the first insulation film with the dummy plug buried in;    forming in the second insulation film an opening for exposing at least a part of the dummy plug;    selectively removing the dummy plug through the opening; and    forming in the contact hole and the opening a first electrode electrically connected to the substrate.    
     
     
         7 . A method for fabricating a semiconductor device according to  claim 6 , wherein 
 in the step of removing the dummy plug, at least a part of the dummy plug is left on the bottom of the contact hole.    
     
     
         8 . A method for fabricating a semiconductor device comprising the steps of: 
 forming on a substrate a first insulation film having a contact hole formed therein;    forming on the first insulation film a second insulation film, leaving a void in the contact hole;    forming in the second insulation film an opening down to the void; and    forming in the contact hole and the opening a first electrode, electrically connected to the substrate.    
     
     
         9 . A method for fabricating a semiconductor device according to  claim 6 , further comprising, after the step of forming the first electrode, the steps of: 
 selectively removing the second insulation film;    forming a dielectric film on the first electrode; and    forming on the dielectric film a second electrode, opposed to the first electrode interposing the dielectric film therebetween.    
     
     
         10 . A method for fabricating a semiconductor device according to  claim 6 , further comprising, after the step of forming the first insulation film, the step of: 
 forming at least in an inside wall and a bottom of the contact hole a conducting film for improving adhesion between the first insulation film and the first electrode or prohibiting reaction between the substrate and the first electrode.    
     
     
         11 . A method for fabricating a semiconductor device according to  claim 6 , further comprising, after the step of forming the opening, the step of: 
 forming on an inside wall and a bottom of the opening and an inside wall and a bottom of the contact hole a conducting film for improving adhesion between the first insulation film and the first electrode or prohibiting reaction between the substrate and the first electrode.    
     
     
         12 . A method for fabricating a semiconductor device according to  claim 10 , wherein 
 in the step of forming the conducting film, the conducting film is formed, extended over the first insulation film, and    in the step of removing the second insulation film, the second insulation film is removed with the conducting film as a stopper.    
     
     
         13 . A method for fabricating a semiconductor device according to  claim 9 , 
 further comprising, between the step of forming the first insulation film and the step of forming the second insulation film, the step of forming a third insulation film having etching characteristics which are different from those of the first insulation film and those of the second insulation film,    in which in the step of removing the second insulation film, the second insulation film is removed with the third insulation film as a stopper.    
     
     
         14 . A method for fabricating a semiconductor device according to  claim 9 , wherein 
 in the step of forming the first insulation film, the first insulation film having etching characteristics of at least a surface region which are different from those of the second insulation film is formed, and    in the step of removing the second insulation film, the second insulation film is removed with the first insulation film as a stopper.    
     
     
         15 . A method for fabricating a semiconductor device according to  claim 9 , wherein 
 the substrate has a first region including a region where the first electrode and the second electrode are formed, and a second region which is different from the first region, and    in the step of removing the second insulation film, the second insulation film in the first region is selectively removed.    
     
     
         16 . A method for fabricating a semiconductor device comprising the steps of: 
 forming on a substrate a first insulation film having a contact hole formed therein;    forming a dummy plug in the contact hole;    forming a second insulation film on the first insulation film with the dummy plug buried in;    forming in the second insulation film an opening for exposing at least a part of the dummy plug;    selectively removing the dummy plug through the opening; and    forming in the contact hole and the opening a conducting film, electrically connected to the substrate.    
     
     
         17 . A method for fabricating a semiconductor device comprising the steps of: 
 forming on a substrate a first insulation film having a contact hole formed therein;    forming on the first insulation film a second insulation film, leaving a void in the contact hole;    forming in the second insulation film an opening down to the void; and    forming in the contact hole and the opening a conducting film, electrically connected to the substrate.