Method for fabricating gate oxide

Abstract

A method for fabricating gate oxide includes a dilute wet oxidation process with additional nitrogen and moisture and an annealing process with a nitrogen base gas, wherein the volume of additional nitrogen is about 6-12 6-20 times of the volume of the additional moisture. The method according to the invention improves the electrical quality of the gate oxide by raising the Q bd and by reducing the leakage current of the gate oxide.

1. A method for fabricating gate oxide, the method comprising:
 providing a silicon substrate;  
 forming the gate oxide by performing a dilute wet oxidation process with additional nitrogen and moisture, wherein the nitrogen has a volume of about 6 to 12  20 times the moisture's volume; and  
 performing an annealing process with a nitrogen base gas on the gate oxide.  
 
     
     
       2. The method of  claim 1 , wherein the dilute wet oxidation is performed at a first temperature of about 750°-900° C. 
     
     
       3. The method of  claim 1 , wherein the annealing process is performed at a second temperature of about 800°-1200° C. 
     
     
       4. The method of  claim 1 , wherein the nitrogen base gas includes N 2 O. 
     
     
       5. The method of  claim 1 , wherein the nitrogen base gas includes NO.