Thin film dielectrics with perovskite structure and preparation thereof

Abstract

Methods of making a ternary oxide and a perovskite-related ternary oxide structure are described. The methods include reacting a binary oxide with a metal oxide or a metal hydroxide to form a ternary oxide dielectric layer on a substrate. Powders, anodes, pressed articles, and capacitors including the ternary oxide or perovskite-related ternary oxide structure as a dielectric layer or other layers are further described.

1 . A method of making a ternary oxide comprising: 
 reacting a binary oxide with a metal material to form a ternary oxide dielectric layer on a substrate, wherein said metal material is different than said binary oxide, wherein said metal material is a metal oxide, a metal carbonate, a metal nitrate, a metal halide, a metal hydroxide, a metal fluoride, or combinations thereof.    
     
     
         2 . The method of  claim 1 , wherein said reacting is achieved in a reactor.  
     
     
         3 . The method of  claim 1 , wherein said binary oxide comprises a transition metal oxide.  
     
     
         4 . The method of  claim 3 , wherein said transition metal oxide comprises Nb 2 O 5 , Ta 2 O 5 , TiO 2 , or combinations thereof.  
     
     
         5 . The method of  claim 1 , further comprising forming said binary oxide on said substrate by an anodization process prior to said reacting.  
     
     
         6 . The method of  claim 1 , wherein said metal material is an alkali oxide or an alkaline earth oxide, Li 2 O, K 2 O, Na 2 O, BaO, or combinations thereof, and wherein said binary oxide is Nb 2 O 5 , Ta 2 O 5 , TiO 2 , or combinations thereof.  
     
     
         7 . The method of  claim 1 , wherein said metal material is an alkali oxide or an alkaline earth oxide.  
     
     
         8 . The method of  claim 1 , wherein said metal material is a metal oxide and includes a metal to oxide ratio of about 2:1, 1:1, or 2:3.  
     
     
         9 . The method of  claim 1 , further comprising generating said metal material by decomposing a compound that produces said metal material.  
     
     
         10 . The method of  claim 9 , wherein said compound is Li 2 CO 3 , Na 2 CO 3 , K 2 CO 3 , BaCO 3 , or combinations thereof.  
     
     
         11 . The method of  claim 10 , wherein said decomposing of said compound produces Li 2 O, Na 2 O, K 2 O, BaO, or combinations thereof respectively.  
     
     
         12 . The method of  claim 1 , wherein said substrate is a metal substrate.  
     
     
         13 . The method of  claim 1 , wherein said substrate is a valve metal substrate or valve metal suboxide substrate.  
     
     
         14 . The method of  claim 1 , wherein said substrate is a conductive metal or metal oxide substrate.  
     
     
         15 . The method of  claim 1 , wherein said substrate is a refractory metal substrate.  
     
     
         16 . The method of  claim 1 , wherein said substrate is tantalum and said ternary oxide is a ternary tantalum oxide.  
     
     
         17 . The method of  claim 1 , wherein said substrate is niobium and said ternary oxide is a ternary niobium oxide.  
     
     
         18 . The method of  claim 1 , wherein reacting comprises contacting a supercritical fluid with said metal oxide and said binary oxide, and wherein said binary oxide is disposed on said substrate.  
     
     
         19 . The method of  claim 18 , wherein said metal oxide is at least partially solubilized in said supercritical fluid.  
     
     
         20 . The method of  claim 18 , wherein said supercritical fluid comprises HCl, H 2 O, NH 3 , SO 2 , CO 2 , CO, or combinations thereof.  
     
     
         21 . The method of  claim 18 , wherein said supercritical fluid is formed by introducing a gas into a reactor and then placing said gas in a supercritical state.  
     
     
         22 . The method of  claim 18 , wherein said supercritical fluid is introduced into a reactor having disposed therein said metal oxide, and said binary oxide on said substrate.  
     
     
         23 . The method of  claim 18 , wherein said metal oxide is present with said supercritical fluid, and wherein said supercritical fluid and said metal oxide are introduced into a reactor having disposed therein said binary oxide on said substrate.  
     
     
         24 . The method of  claim 18 , wherein said supercritical fluid is present with at least one co-solvent.  
     
     
         25 . The method of  claim 24 , wherein said co-solvent is methanol or water.  
     
     
         26 . The method of  claim 24 , wherein said co-solvent is present with said metal oxide, and wherein said supercritical fluid and said co-solvent are introduced into a reactor having disposed therein said binary oxide on said substrate.  
     
     
         27 . The method of  claim 24 , wherein said co-solvent is introduced with said supercritical fluid into a reactor having disposed therein said metal oxide, and said binary oxide on said substrate.  
     
     
         28 . The method of  claim 24 , wherein said co-solvent is introduced after said supercritical fluid into a reactor having disposed therein said metal oxide, and said binary oxide on said substrate.  
     
     
         29 . The method of  claim 24 , wherein said supercritical fluid and said co-solvent are premixed to form an inlet stream that is introduced into a reactor having disposed therein said metal oxide, and said binary oxide on said substrate.  
     
     
         30 . The method of  claim 24 , wherein said co-solvent and said supercritical fluid are present at a volume ratio of from about 1:10,000 to about 1:10.  
     
     
         31 . The method of  claim 24 , wherein said metal oxide is placed in a reactor and wherein said metal oxide is a solid.  
     
     
         32 . The method of  claim 24 , wherein said co-solvent causes an increase in solubility, transport characteristics, or both in said metal oxide.  
     
     
         33 . The method of  claim 1 , wherein an electrical field is applied to said substrate during said reacting.  
     
     
         34 . The method of  claim 1 , wherein said reacting comprises: 
 heating said metal material at a temperature and a pressure sufficient to melt said metal material to form a molten metal material; and    contacting said molten metal material to said binary oxide, wherein said binary oxide is disposed on said substrate.    
     
     
         35 . The method of  claim 34  wherein said metal material is a metal oxide.  
     
     
         36 . The method of  claim 34 , further comprising stabilizing a film of said binary oxide on said substrate by applying a voltage to said substrate.  
     
     
         37 . The method of  claim 34 , wherein said temperature is from about 150 to about 1200° C.  
     
     
         38 . The method of  claim 34 , wherein said pressure is from about vacuum to about 2 atmosphere absolute.  
     
     
         39 . The method of  claim 34 , wherein said molten metal material comprises a molten salt.  
     
     
         40 . The method of  claim 34 , wherein said binary oxide comprises a transition metal oxide.  
     
     
         41 . The method of  claim 40 , wherein said transition metal oxide comprises Nb 2 O 5 , Ta 2 O 5 , TiO 2 , or combinations thereof.  
     
     
         42 . The method of  claim 34 , further comprising forming said binary oxide on said substrate by an anodization process prior to said reacting.  
     
     
         43 . The method of  claim 34 , wherein said substrate is a metal substrate.  
     
     
         44 . The method of  claim 34 , wherein said substrate is a valve metal substrate or valve metal suboxide substrate.  
     
     
         45 . The method of  claim 34 , wherein said substrate is tantalum and said ternary oxide is a ternary tantalum oxide.  
     
     
         46 . The method of  claim 34 , wherein said substrate is niobium or niobium suboxide and said ternary oxide is a ternary niobium oxide.  
     
     
         47 . The method of claim I, wherein reacting comprises: 
 fusing said binary oxide with said metal material to form a solid material;    dissolving said solid material in a first solution;    disposing said first solution or a derivative of said first solution onto said substrate; and    heating said substrate having said first solution disposed thereon or an evaporated film of the first solution disposed thereon under vacuum.    
     
     
         48 . The method of  claim 47 , wherein said contacting comprises coating, spraying, dipping, exposing to vapors, or combinations thereof.  
     
     
         49 . The method of  claim 47 , wherein said solid material comprises a fused material.  
     
     
         50 . The method of  claim 47 , wherein said first solution comprises water.  
     
     
         51 . The method of  claim 1 , wherein reacting comprises anodizing said binary oxide, wherein said binary oxide comprises an anode, in an electrolyte comprising said metal material.  
     
     
         52 . The method of  claim 51 , wherein said electrolyte comprises a metal hydroxide.  
     
     
         53 . The method of  claim 51 , wherein said electrolyte comprises a molten salt.  
     
     
         54 . The method of  claim 51 , wherein said binary oxide comprises NbO, and said electrolyte comprises NaOH.  
     
     
         55 . The method of  claim 51 , wherein said electrolyte further comprises an oxide ion to initiate said reacting.  
     
     
         56 . The method of  claim 51 , wherein said anode comprises a metal having a layer comprised of said binary oxide.  
     
     
         57 . The method of  claim 1 , wherein said reacting comprises anodizing said binary oxide, wherein said binary oxide comprises an anode, and contracting said binary oxide with at least one molten metal containing at least one dissolved oxide.  
     
     
         58 . An article comprising a ternary metal oxide layer located on at least one substrate.  
     
     
         59 . The article of  claim 58 , wherein said substrate is a valve metal substrate or valve metal suboxide substrate.  
     
     
         60 . The article of  claim 58 , wherein said substrate comprises Ta and/or Nb and/or NbO.  
     
     
         61 . The article of  claim 58 , wherein said ternary metal oxide comprises dopant levels of nitrogen, oxygen, boron, sulfur, phosphorus, or mixtures thereof.  
     
     
         62 . The article of  claim 58 , wherein said ternary metal oxide comprise at least one dopant.  
     
     
         63 . The article of  claim 58 , wherein said ternary oxide has the formula AMO 3 , wherein A is an alkali metal or alkaline earth and M is a metal.  
     
     
         64 . The article of  claim 63 , wherein AMO 3  is a solid solution of at least two ternary oxides.  
     
     
         65 . The article of  claim 58 , wherein said ternary oxide is Na x K (1−x)  NbO 3 , KTa x  Nb (1−x) O 3 , Na x  K (1−x) Ta y  Nb (1−y) O 3 , Ta 2x  Nb (2−2x) O 5 , wherein x is from 0 to 1 and y is from 0 to 1.  
     
     
         66 . A pressed metal article comprising a perovskite-related ternary oxide dielectric layer on a pressed substrate.  
     
     
         67 . The pressed metal article of  claim 66 , wherein said pressed metal substrate is at least one valve metal or valve metal suboxide.  
     
     
         68 . The capacitor of  claim 66 , wherein said anode comprises at least one valve metal or alloys thereof.  
     
     
         69 . The pressed metal article of  claim 66 , wherein said metal article is an anode.  
     
     
         70 . The pressed metal article of  claim 66 , wherein said perovskite-related ternary oxide is LiNbO 3 , KNbO 3 , KTaO 3 , or BaTiO 3 , NaNbO 3 , NaTaO 3 , or a perovskite-related compound that is a solid solution of two or more perovskite ternary oxides.  
     
     
         71 . The article of  claim 58 , wherein said ternary oxide is LiNbO 3 , KNbO 3 , KTaO 3 , or BaTiO 3 , NaNbO 3 , NaTaO 3 , or a compound that is a solid solution of two or more ternary oxides.  
     
     
         72 . The pressed metal article of  claim 66 , wherein said pressed metal substrate is Nb.  
     
     
         73 . The pressed metal article of  claim 66 , wherein said pressed metal substrate is Ta.  
     
     
         74 . A capacitor comprising a perovskite-related ternary oxide dielectric layer on an anode.  
     
     
         75 . The capacitor of  claim 74 , wherein said anode comprises Ta and said perovskite-related ternary oxide is a ternary tantalum oxide.  
     
     
         76 . The capacitor of  claim 74 , wherein said anode comprises Nb and said perovskite-related ternary oxide is LiNbO 3 , KNbO 3 , Na NbO 3 , NaTaO 3 , or combinations thereof.  
     
     
         77 . The capacitor of  claim 74 , wherein said anode comprises Ta and said perovskite-related ternary oxide is NaTaO 3  or KTaO 3 .  
     
     
         78 . The capacitor of  claim 74 , wherein said anode comprises Nb or NbO, and said perovskite-related ternary oxide is a ternary niobium oxide.  
     
     
         79 . A capacitor comprising a perovskite-related ternary oxide.  
     
     
         80 . A capacitor comprising a perovskite-related compound that is a solid solution of two or more perovskite-related ternary oxides.  
     
     
         81 . An anode comprising a perovskite-related ternary oxide dielectric layer.  
     
     
         82 . An anode comprising a dielectric layer comprising a perovskite-related compound that is a solid solution of two or more perovskite-related ternary oxides.  
     
     
         83 . The method of  claim 1 , wherein said substrate is an anode.  
     
     
         84 . The method of  claim 1 , wherein said substrate is an anode and said binary oxide is formed on said anode by an anodization process prior to said reacting.  
     
     
         85 . An anode having a dielectric layer formed by the method of  claim 83 .  
     
     
         86 . An anode having a dielectric layer formed by the method of  claim 84 .  
     
     
         87 . A capacitor comprising the anode of  claim 85 .  
     
     
         88 . A capacitor comprising the anode of  claim 86.