Etched metal oxide film

Abstract

Metal oxide films are etched with a metal and an etch liquid containing an acid and a metal penetration control agent.

What is claimed as new and desired to be secured by Letters Patent of the United States is:  
     
         1 . An M-A-P method of etching a masked metal oxide film on a substrate in which a metal (M) and an etch liquid comprising acid (A) and a Ni ++  reduced metal oxide metal penetration control agent (P) are brought into contact with said masked metal oxide film such that the metal oxide is reduced to its metallic form through the action of active hydrogen (H 0 ) produced in the reaction of M with A, and in which etching stops when the reduced metal oxide become impenetrable to H 0 .  
     
     
         2 . The method of    claim 1   , wherein the metal oxide is tin oxide, the metal (M) is zinc and the acid (A) is hydrochloric acid in a concentration of 0.1-2.0 M H +  and the penetration control agent (P) is NiCl 2  in a concentration of 0.001-0.2 M Ni ++ .  
     
     
         3 . The method of    claim 1   , wherein the metal oxide is tin oxide, the metal (M) is zinc and the acid (A) is hydrochloric acid in a concentration of 0.1-1.5 M H +  and the penetration control agent (P) is NiCl 2  in a concentration of 0.003-0.02 M Ni ++ .  
     
     
         4 . The method of    claim 1   , wherein the reduced metal oxide is dissolved in an acid bath containing an oxidizing agent.  
     
     
         5 . The method of    claim 2   , wherein the reduced tin oxide is dissolved in an acid bath containing an oxidizing agent.  
     
     
         6 . The method of    claim 1   , wherein said method is carried out successively to progressively etch a film of a metal oxide.  
     
     
         7 . The method of    claim 2   , wherein said method is carried out successively to progressively etch a film of tin oxide.  
     
     
         8 . The method of    claim 1   , wherein a slurry of said metal (M) with said etch liquid is deposited on said masked metal oxide film.  
     
     
         9 . An etched metal oxide film prepared by the method of    claim 1   .  
     
     
         10 . The etched metal oxide film of    claim 9   , wherein the metal oxide film is a tin oxide film.