Semiconductor device and method of manufacturing same

Abstract

A semiconductor device is produced by forming a gate oxide film on a silicon substrate, forming a gate electrode on the gate oxide film, forming a nitrogen-containing oxide film on the silicon substrate and gate electrode in an N 2 O gas or an NO gas, forming a BPSG film on the nitrogen-containing oxide film, and carrying out a reflow process on the BPSG film in a water vapor atmosphere. During the reflow process, the nitrogen-containing oxide film that has no hydrogen atoms prevents the penetration and diffusion of oxygen and hydrogen atoms into the silicon substrate and gate electrode, thereby preventing the oxidization of the silicon substrate and gate electrode. No hydrogen atoms diffuse into the gate oxide film, and therefore, the reliability of the gate oxide film is secured.

1 - 22 . (canceled)  
   
   
       23 . A semiconductor device comprising: 
 a semiconductor substrate;    a first insulating film formed on the semiconductor substrate so that a contact face between the first insulating film and the substrate has two first edges that run in parallel with each other;    a conductive film formed on the first insulating film so that a contact face between the conductive film and the first insulating film has two second edges that run in parallel with the first edges;    a nitrogen-containing silicon oxide film having a first face that is in contact with side faces of the first insulating film defined by the first edges, side faces of the conductive film defined by the second edges, and surface areas of the semiconductor substrate defined by the first edges, and contacting with both the semiconductor substrate and the first insulating film at the first edges, and configure to prevent said semiconductor substrate from oxidizing and a thickness of said first insulating film from enlarging; and    a boron-doped phosphorus silicate glass (BPSG) film formed over the conductive film and on a second face, which is opposite to the first face, of the nitrogen-containing silicon oxide film.    
   
   
       24 . The semiconductor device of  claim 23 , further comprising: 
 a second insulating film formed on the conductive film under the nitrogen-containing silicon oxide film, wherein a contact face between the second insulating film and the conductive film has two third edges that run in parallel with the first edges.    
   
   
       25 . The semiconductor device of  claim 23 , wherein the conductive film has a multilayer structure consisting of: 
 a first conductive film made of polysilicon or polycrystalline silicon; and    a second conductive film made of refractory metal or a silicide of refractory metal, formed on the first conductive film.    
   
   
       26 . The semiconductor device of  claim 23 , wherein the conductive film has a multilayer structure consisting of: 
 a lower conductive film;    a third insulating film formed on the lower conductive film; and    an upper conductive film formed on the third insulating film.    
   
   
       27 . The semiconductor device of  claim 26 , wherein the upper conductive film has a multilayer structure consisting of: 
 a first conductive film made of polysilicon or polycrystalline silicon; and    a second conductive film made of refractory metal or a silicide of refractory metal, formed on the first conductive film.    
   
   
       28 . The semiconductor device of  claim 24 , wherein the nitrogen-containing silicon oxide film covers the top and side faces of the second insulating film.  
   
   
       29 . The semiconductor device of  claim 24 , wherein the second insulating film is made of silicon oxide or silicon nitride.  
   
   
       30 . The semiconductor device of  claim 24 , wherein: 
 the second insulating film is made of silicon nitride; and    the BPSG film covers the top and side faces of the second insulating film.    
   
   
       31 . The semiconductor device of  claim 23 , wherein the semiconductor substrate has: 
 a first semiconductor region of a first conductivity type, including the contact face between the first insulating film and the semiconductor substrate;    a second semiconductor region of a second conductivity type, formed in a surface area of the semiconductor substrate that involves one of the first edges and is in contact with the first semiconductor region; and    a third semiconductor region of the second conductivity type, formed in a surface area of the semiconductor substrate that involves the other of the first edges and is in contact with the first semiconductor region.    
   
   
       32 . A semiconductor device, comprising: 
 a semiconductor substrate;    a first insulating film formed on the semiconductor substrate and in direct contact with the semiconductor substrate, wherein a contact face between the first insulating film and the substrate has two first edges that run in parallel with each other;    a first conductive film formed on the first insulating film and in direct in contact with the first insulating film, wherein a contact face between the first conductive film and the first insulating film has two second edges that run in parallel with the first edges;    a second conductive film formed on the first conductive film and in direct contact with the first conductive film, wherein a contact face between the second conductive film and the first conducting film has two third edges that run in parallel with the second edges;    a nitrogen-containing silicon oxide film that covers and that is in direct contact with the side faces of the first insulating film, the first conductive film and the second conductive film at the first, second and third edges, and wherein the nitrogen-containing silicon oxide film is in direct contact with the contact face of the second conducting film opposite the first conductive film; and    a boron-doped phosphorus silicate glass film is present over the first insulating film, the first and second conductive films and the nitrogen-containing silicon oxide film.    
   
   
       33 . The semiconductor device of  claim 32 , wherein the second conductive film comprises a refractory metal or a silicide of a refractory metal.  
   
   
       34 . The semiconductor device of  claim 32 , wherein the first conductive film is made of polysilicon or polycrystalline silicon; and the second conductive film is made of a refractory metal or a silicide of a refractory metal.  
   
   
       35 . A semiconductor device, comprising: 
 a semiconductor substrate;    a first insulating film formed on the semiconductor substrate and in direct contact with the semiconductor substrate, wherein a contact face between the first insulating film and the semiconductor substrate has two first edges that run in parallel with each other;    a first conductive film formed on the first insulating film and in direct contact with the first insulating film, wherein a contact face between the first insulating film and the first conductive film has two second edges that run in parallel with the first edges;    a first oxide film formed on the first conductive film and in direct contact with the first conductive film, wherein a contact face between the first oxide film and the first conductive film has two third edges that run in parallel with the second edges;    a second conductive film formed on the first oxide film and in direct contact with the first oxide film, wherein a contact face between the second conductive film and the first oxide film has two fourth edges that run in parallel with the third edges;    a third conductive film formed on the second conductive film and in direct contact with the second conductive film, wherein a contact face between the second conducting film and the third conducting film has two fifth edges that run in parallel with the fourth edges;    a second oxide film formed on the third conductive film and in direct contact with the third conductive film, wherein a contact face between the third oxide film and the second conductive film has two sixth edges that run in parallel with the fifth edges;    a nitrogen containing oxide film in contact with the edges of each of the films and covering the second oxide film and the substrate.    
   
   
       36 . The semiconductor device of  claim 35 , wherein the first conductive film is made of at least one of polysilicon or polycrystalline silicon, the second conductive film is made of at least one of a polysilicon or polycrystalline silicon, the third conductive film is made of at least one of refractory metal or a silicide of a refractory metal.