Durable sputtered metal oxide coating

Abstract

A method and resultant product are disclosed wherein a metal film is deposited by sputtering a metal cathode target in an essentially nonreactive atmosphere comprising inert gas and a reactive gas, wherein the concentration of reactive gas is sufficiently low that the sputtering is accomplished in the metallic mode, i.e. the film is deposited as metal. The metal film of the present invention is harder than a metal film sputtered in an atmosphere consisting of only inert gas. The method and resultant product may further comprise thermal oxidation of the metal film, which proceeds more efficiently than oxidation of a metal film sputtered in an atmosphere consisting of only inert gas.

1 . A method of producing a hard metal film by cathode sputtering comprising the steps of: 
 a. placing a substrate in an evacuated chamber comprising an atmosphere comprising inert gas and a reactive gas; and    b. sputtering a metal cathode target wherein the concentration of reactive gas is sufficiently low that the metal is sputtered in the metallic mode to deposit a metal film.    
     
     
         2 . A method according to  claim 1 , wherein the metal is selected from the group consisting of titanium, zirconium, tantalum, hafnium, niobium, vanadium and mixtures thereof.  
     
     
         3 . A method according to  claim 2 , wherein the metal is selected from the group consisting of titanium and zirconium.  
     
     
         4 . A method according to  claim 3 , wherein the metal is titanium.  
     
     
         5 . A method according to  claim 1 , wherein the reactive gas is selected from the group consisting of oxygen and nitrogen.  
     
     
         6 . A method according to  claim 5 , wherein the reactive gas is oxygen.  
     
     
         7 . A method according to  claim 1 , wherein the inert gas is argon.  
     
     
         8 . A method according to  claim 7 , wherein the atmosphere comprises argon and up to 30 percent oxygen.  
     
     
         9 . A method according to  claim 1 , comprising the further step of thermally oxidizing the metal film.  
     
     
         10 . A method according to  claim 9 , comprising the further step of depositing a metal oxide layer over the metal film prior to the step of thermally oxidizing the metal film.  
     
     
         11 . A product prepared by the method of  claim 1 .  
     
     
         12 . A product prepared by the method of  claim 2 , wherein the metal is selected from the group consisting of titanium, zirconium, tantalum, hafnium, niobium, vanadium and mixtures thereof.  
     
     
         13 . A product prepared by the method of  claim 2 , wherein the metal is selected from the group consisting of titanium and zirconium.  
     
     
         14 . A product prepared by the method of  claim 3 , wherein the metal is titanium.  
     
     
         15 . A product prepared by the method of  claim 1 , wherein the reactive gas is selected from the group consisting of oxygen and nitrogen.  
     
     
         16 . A product prepared by the method of  claim 5 , wherein the reactive gas is oxygen.  
     
     
         17 . A product prepared by the method of  claim 1 , wherein the inert gas is argon.  
     
     
         18 . A product prepared by the method of  claim 7 , wherein the atmosphere comprises argon and up to 30 percent oxygen.  
     
     
         19 . A product prepared by the method of  claim 1 , wherein the metal film is thermally oxidized.  
     
     
         20 . A product prepared by the method of  claim 9 , further comprising a metal oxide film deposited on the metal film prior to thermal oxidation of the metal film.