Gate structure and method

Abstract

A MOSFET structure with high-k gate dielectrics for silicon or metal gates with gate dielectric liquid-based oxidation surface treatments prior to gate material deposition and gate formation.

1 . A method of field effect transistors, comprising: 
 (a) forming a dielectric layer on a semiconductor substrate, said dielectric layer including M w Si x O y N z  with M a metal selected from the group consisting of Hf, Zr, La, Gd, Pr, Y, and mixtures thereof;    (b) exposing said dielectric layer to a oxidizing liquid solution; and    (c) forming gates on said dielectric layer after said exposing of step (b).    
   
   
       2 . The method of  claim 1 , wherein: 
 (a) said exposing of step (b) of  claim 1  is by immersing said dielectric layer and substrate in said liquid solution.    
   
   
       3 . The method of  claim 1 , wherein: 
 (a) said exposing of step (b) of  claim 1  is by spraying in said liquid solution onto said dielectric layer.    
   
   
       4 . The method of  claim 1 , wherein: 
 (a) said solution is H 2 O 2  plus H 2 O.    
   
   
       5 . The method of  claim 1 , wherein: 
 (a) said solution is taken from the group consisting of H 2 SO 4 +H 2 O 2 +H 2 O, H 2 SO 4 +H 2 O, HNO 3 +H 2 O, HNO 3 +H 2 O 2 +H 2 O, HCl+H 2 O 2 +H 2 O; NH 4 OH+H 2 O 2 +H 2 O; and H 2 O+O 3 .    
   
   
       6 . The method of  claim 1 , further comprising the step of: 
 (a) after said exposing of step (b) of  claim 1  but prior to said gate forming step (c) of  claim 1 , annealing said dielectric layer in an inert atmosphere.    
   
   
       7 . The method of  claim 1 , further comprising the step of: 
 (a) after said forming of step (a) of  claim 1  but prior to said exposing step (b) of  claim 1 , annealing said dielectric layer in an inert atmosphere.    
   
   
       8 . The method of  claim 1 , wherein: 
 (a) M is Hf; and    (b) the ratio of x to w is in the range of 0 to 10.    
   
   
       9 . A gate dielectric material, comprising: 
 (a) M w M′ x O y N z  where M is taken from the group consisting of Hf, Zr, La, Gd, Pr, Y, and mixtures thereof, and M′ is taken from the group consisting of Al, Si, and mixtures thereof;    (b) wherein the ratio of w+x to y+z is roughly 1 to 2; and    (c) wherein the ratio of z to y is in the range of 0.005 to 2.    
   
   
       10 . The material of  claim 9 , wherein: 
 (a) M w M′ x O y N z  is Hf w Si x O y N z  with w in the range of 6 to 15, x in the range of 20 to 25, y in the range of 33 to 55, and z in the range of 16 to 32.