Semiconductor device and method for manufacturing the same

Abstract

A semiconductor device includes a semiconductor substrate, a first insulating film provided on the semiconductor substrate, a charge storage layer provided on the first insulating film, a second insulating film comprising a plurality of insulating films provided on the charge storage layer and comprising a nitride film as an uppermost layer, and a single-layer control gate electrode provided on the second insulating film and comprising metal silicide.

1 . A semiconductor device comprising: 
 a semiconductor substrate;    a first insulating film provided on the semiconductor substrate;    a charge storage layer provided on the first insulating film;    a second insulating comprising a plurality of insulating films provided on the charge storage layer and comprising a nitride film as an uppermost layer; and    a single-layer control gate electrode provided on the second insulating film and comprising metal silicide.    
   
   
       2 . The semiconductor device according to  claim 1 , wherein the uppermost layer is a nitride film including Si—N bond.  
   
   
       3 . The semiconductor device according to  claim 1 , wherein the second insulating film is an insulating film whose uppermost layer is a nitride film and includes at least one of an oxide film, a nitride film, an oxynitride film, a high-dielectric metal oxide film, a high-dielectric metal nitride film, and a high-dielectric metal oxynitride film.  
   
   
       4 . The semiconductor device according to  claim 2 , wherein the second insulating film is an insulating film whose uppermost layer is a nitride film and includes at least one of an oxide film, a nitride film, an oxynitride film, a high-dielectric metal oxide film, a high-dielectric metal nitride film, and a high-dielectric metal oxynitride film.  
   
   
       5 . The semiconductor device according to  claim 1 , wherein thickness of the nitride film is not less than 0.5 nm and not higher than 3 nm.  
   
   
       6 . The semiconductor device according to  claim 2 , wherein thickness of the nitride film is not less than 0.5 nm and not higher than 3 nm.  
   
   
       7 . The semiconductor device according to  claim 1 , wherein the metal silicide includes at least one of Ni, Co, and Pt.  
   
   
       8 . The semiconductor device according to  claim 2 , wherein the metal silicide includes at least one of Ni, Co, and Pt.  
   
   
       9 . A semiconductor device comprising: 
 a semiconductor substrate;    a first insulating film provided on the semiconductor substrate;    a charge storage layer provided on the first insulating film;    a second insulating film provided on the charge storage layer; and    a multilayer control gate electrode provided on the second insulating film and comprising a semiconductor film, a third insulating film whose an uppermost layer is a nitride film, and a metal silicide film provided on the third insulating film.    
   
   
       10 . The semiconductor device according to  claim 9 , wherein the uppermost layer is a nitride film including Si—N bond.  
   
   
       11 . The semiconductor device according to  claim 9 , wherein the third insulating film is an insulating film whose uppermost layer is a nitride film and includes at least one of an oxide film, a nitride film, an oxynitride film, a high-dielectric metal oxide film, a high-dielectric metal nitride film, and a high-dielectric metal oxynitride film.  
   
   
       12 . The semiconductor device according to  claim 10 , wherein the third insulating film is an insulating film whose uppermost layer is a nitride film and includes at least one of an oxide film, a nitride film, an oxynitride film, a high-dielectric metal oxide film, a high-dielectric metal nitride film, and a high-dielectric metal oxynitride film.  
   
   
       13 . The semiconductor device according to  claim 9 , wherein thickness of the nitride film is not less than 0.5 nm and not higher than 2 nm.  
   
   
       14 . The semiconductor device according to  claim 10 , wherein thickness of the nitride film is not less than 0.5 nm and not higher than 2 nm.  
   
   
       15 . The semiconductor device according to  claim 9 , wherein the metal silicide includes at least one of Ni, Co, and Pt.  
   
   
       16 . The semiconductor device according to  claim 10 , wherein the metal silicide includes at least one of Ni, Co, and Pt.  
   
   
       17 . A method for manufacturing a semiconductor device comprising a nonvolatile semiconductor memory including a semiconductor substrate and a gate structure provided on the semiconductor substrate, the gate structure comprising an insulating film and a control gate electrode provided on the insulating film, the method comprising: 
 forming an insulating film whose uppermost layer is a nitride film as the insulating film of the gate structure;    forming a semiconductor film on the insulating film;    processing the semiconductor film and the insulating film into a gate;    forming a refractory metal film on an area including the semiconductor film; and    forming a single-layer control gate electrode comprising a metal silicide film, the forming the control gate electrode comprising converting whole of the semiconductor film into a metal silicide film by heat treatment.    
   
   
       18 . The method for manufacturing a semiconductor device according to  claim 17 , wherein the semiconductor film is amorphous.  
   
   
       19 . The method for manufacturing a semiconductor device according to  claim 17 , wherein the insulating film and the semiconductor film are formed in the same chamber.  
   
   
       20 . The method for manufacturing a semiconductor device according to  claim 17 , wherein the second insulating film is an insulating film whose uppermost layer is a nitride film and includes at least one of an oxide film, a nitride film, an oxynitride film, a high-dielectric metal oxide film, a high-dielectric metal nitride film, and a high-dielectric metal oxynitride film.