Semiconductor device and manufacturing method therefor

Abstract

A method of manufacturing a semiconductor device comprises forming a gate insulation film on a semiconductor substrate; forming a first gate electrode and a second gate electrode on the gate insulation film; forming a mask material so as to expose an upper surface of the first gate electrode while keeping the second gate electrode covered; etching an upper part of the first gate electrode by using the mask material as a mask; removing the mask material; depositing a metal film on the first gate electrode and the second gate electrode; and siliciding the whole of the first gate electrode and an upper part of the second gate electrode.

1 . A method of manufacturing a semiconductor device comprising: 
 forming a gate insulation film on a semiconductor substrate;    forming a first gate electrode and a second gate electrode on the gate insulation film;    forming a mask material so as to expose an upper surface of the first gate electrode while keeping the second gate electrode covered;    etching an upper part of the first gate electrode by using the mask material as a mask;    removing the mask material;    depositing a metal film on the first gate electrode and the second gate electrode; and    siliciding the whole of the first gate electrode and an upper part of the second gate electrode.    
   
   
       2 . The method of manufacturing a semiconductor device according to  claim 1 , wherein 
 a bottom part of the second gate electrode is made of polysilicon.    
   
   
       3 . The method of manufacturing a semiconductor device according to  claim 1 , wherein 
 the metal film is made of nickel (Ni).    
   
   
       4 . A method of manufacturing a semiconductor device comprising: 
 forming a gate insulation film on a semiconductor substrate;    forming a first gate electrode and a second gate electrode on the gate insulation film;    forming a mask material so as to expose an upper surface of the second gate electrode while keeping the first gate electrode covered;    forming a silicidation restricting layer inside the second gate electrode, the silicidation restricting layer being less easily silicided than a material of the first and the second gate electrodes;    removing the mask material;    depositing a metal film on the first gate electrode and the second gate electrode; and    siliciding the whole of the first gate electrode and an upper part above the silicidation restricting layer in the second gate electrode.    
   
   
       5 . The method of manufacturing a semiconductor device according to  claim 4 , wherein 
 the silicidation restricting layer is formed by implanting nitrogen (N) into the second gate electrode.    
   
   
       6 . A method of manufacturing a semiconductor device comprising: 
 forming a gate insulation film on a semiconductor substrate;    forming a first gate electrode and a second gate electrode on the gate insulation film;    forming a mask material so as to expose an upper surface of the first gate electrode while keeping the second gate electrode covered;    amorphizing an upper part of the first gate electrode by using the mask material as a mask;    removing the mask material;    depositing a metal film on the first gate electrode and the second gate electrode; and    siliciding the whole of the first gate electrode and an upper part of the second gate electrode.    
   
   
       7 . The method of manufacturing a semiconductor device according to  claim 6 , wherein 
 when the upper part of the first gate electrode is amorphized, germanium or silicon are implanted into the first gate electrode.    
   
   
       8 . A method of manufacturing a semiconductor device comprising: 
 forming a gate insulation film on a semiconductor substrate;    depositing a gate electrode material on the gate insulation film;    depositing a silicidation restricting material on the gate electrode material, the silicidation restricting material being less easily silicided than the gate electrode material;    forming a first gate electrode and a second gate electrode, which have the silicidation restricting material on the upper surfaces thereof, on the gate insulation film by patterning the silicidation restricting material and the gate electrode material;    forming a mask material on the silicidation restricting material on the upper surfaces of the first and the second gate electrodes;    patterning the mask material so as to expose an upper surface of the silicidation restricting material on the first gate electrode while keeping the silicidation restricting material on the second gate electrode covered;    removing the silicidation restricting material on the first gate electrode by using the mask material as a mask;    removing the mask material;    depositing a metal film on the first gate electrode and the second gate electrode; and    siliciding the first gate electrode.    
   
   
       9 . The method of manufacturing a semiconductor device according to  claim 8 , wherein 
 the silicidation restricting material is made of a silicon nitride film.    
   
   
       10 . A method of manufacturing a semiconductor device comprising: 
 forming a gate insulation film on a semiconductor substrate;    forming a first gate electrode and a second gate electrode on the gate insulation film;    depositing a metal film on the first gate electrode and the second gate electrode;    depositing a heat shielding film on the metal film;    patterning the heat shielding film so as to expose the metal film on the first gate electrode while keeping the metal film on the second gate electrode covered; and    siliciding the whole of the first gate electrode and an upper part of the second gate electrode.    
   
   
       11 . The method of manufacturing a semiconductor device according to  claim 10 , wherein 
 the heat shielding film is made of a material which does not react with the metal film.    
   
   
       12 . The method of manufacturing a semiconductor device according to  claim 10 , wherein 
 the heat shielding film is made of a material that is dissolved in hydrogen peroxide solution and sulfuric acid solution.    
   
   
       13 . The method of manufacturing a semiconductor device according to  claim 10 , wherein 
 the whole of the first gate electrode and an upper part of the second gate electrode are silicided by using a lamp heating apparatus or a light heating apparatus.    
   
   
       14 . A method of manufacturing a semiconductor device comprising: 
 forming a gate insulation film on a semiconductor substrate;    depositing a gate electrode material on the gate insulation film;    depositing a cap material covering the gate electrode material;    forming a first gate electrode and a second gate electrode, which have the cap material on the upper surfaces thereof, on the gate insulation film by patterning the cap material and the gate electrode material;    forming a sidewall film on sidewalls of the first and the second gate electrodes and the cap material;    forming trenches on the first and the second gate electrodes by removing the cap material;    forming a mask material so as to expose an upper surface of the first gate electrode while keeping the second gate electrode covered;    etching the upper part of the first gate electrode by using the mask material as a mask;    removing the mask material;    filling a metal material in the trenches on the first and the second gate electrodes; and    siliciding the whole of the first gate electrode and an upper part of the second gate electrode.    
   
   
       15 . The method of manufacturing a semiconductor device according to  claim 14 , wherein 
 the cap material is made of a silicon nitride.    
   
   
       16 . A semiconductor device comprising: 
 a semiconductor substrate;    a gate insulation film provided on the semiconductor substrate;    a first gate electrode provided on the gate insulation film and used for a core circuit part of the semiconductor device, the first gate electrode being wholly silicided; and    a second gate electrode provided on the gate insulation film and used for a peripheral circuit part of the semiconductor device, the second gate electrode having a laminated structure including a polysilicon layer and a silicide layer.    
   
   
       17 . The semiconductor device according to  claim 16  further comprising: 
 a silicidation restricting layer provided below the suicide layer in the second gate electrode, the silicidation restricting layer being less easily silicided than polysilicon.    
   
   
       18 . A semiconductor device comprising: 
 a semiconductor substrate;    a gate insulation film provided on the semiconductor substrate;    a first gate electrode provided on the gate insulation film, the first gate electrode being wholly silicided; and    a second gate electrode provided on the gate insulation film, the second gate electrode having a laminated structure including a polysilicon layer and a silicide layer, wherein    the film thickness of the first gate electrode is formed smaller than that of the second gate electrode.    
   
   
       19 . The semiconductor device according to  claim 18 , wherein 
 the silicide layer is made of nickel silicide.    
   
   
       20 . The semiconductor device according to  claim 18 , wherein 
 the first gate electrode includes germanium (Ge).