Tailoring nitrogen profile in silicon oxynitride using rapid thermal annealing with ammonia under ultra-low pressure

Abstract

A method of forming a dielectric film that includes nitrogen. The method includes incorporating nitrogen into a dielectric film using a nitridation gas and a rapid thermal annealing process, wherein an ultra-low pressure of equal to or less than about 10 Torr is used for the rapid thermal annealing process.

1 . A nitrogen-containing dielectric film, comprising: a dielectric material; and a total amount of nitrogen incorporated into the dielectric material, the total amount of nitrogen having a concentration peak occurring at the top surface of the dielectric film. 
   
   
       2 . The nitrogen-containing dielectric film of  claim 1 , wherein the total amount of nitrogen incorporated into the dielectric film has an atomic concentration equal to or greater than 5% of the nitrogen-containing dielectric film. 
   
   
       3 . The nitrogen-containing dielectric film of  claim 1 , wherein the dielectric material has a thickness equal to or less than about 12 angstroms. 
   
   
       4 . The nitrogen-containing dielectric film of  claim 1 , wherein the dielectric material is silicon dioxide (SiO 2 ). 
   
   
       5 . The nitrogen-containing dielectric film of  claim 1 , wherein the nitrogen-containing dielectric film is a silicon oxynitride. 
   
   
       6 . A gate stack, comprising:
 a nitrogen-containing dielectric film comprising a dielectric material and a total amount of nitrogen incorporated into the dielectric material, the total amount of nitrogen having a concentration peak occurring at the top surface of the dielectric film; and   a cap layer disposed on the nitrogen-containing dielectric film.   
   
   
       7 . The gate stack of  claim 6 , wherein the total amount of nitrogen incorporated into the dielectric film has an atomic concentration equal to or greater than 5% of the nitrogen-containing dielectric film. 
   
   
       8 . The gate stack of  claim 6 , wherein the dielectric material has a thickness equal to or less than about 12 angstroms. 
   
   
       9 . The gate stack of  claim 6 , wherein the dielectric material is silicon dioxide (SiO 2 ). 
   
   
       10 . The gate stack of  claim 6 , wherein the nitrogen-containing dielectric film is a silicon oxynitride. 
   
   
       11 . A silicon oxynitride film wherein a nitrogen concentration in the silicon oxynitride film is greatest at the top surface of the film and decreasing with depth, and the silicon oxynitride film is free of unassociated nitrogen. 
   
   
       12 . The silicon oxynitride film of  claim 11 , wherein the nitrogen concentration is equal to or greater than 5%. 
   
   
       13 . The silicon oxynitride film of  claim 11 , wherein the silicon oxynitride film has a thickness equal to or less than about 12 angstroms.