Etchant composition and forming method of wiring using etchant composition

Abstract

A phosphoric acid-free etchant composition and a method of forming a wiring, the composition including about 40 wt % to about 60 wt % of an organic acid compound; about 6 wt % to about 12 wt % of a glycol compound; about 1 wt % to about 10 wt % of nitric acid, sulfuric acid, or hydrochloric acid; about 1 wt % to about 10 wt % of a nitrate salt compound; and water, all wt % being based on a total weight of the phosphoric acid-free etchant composition.

What is claimed is: 
     
         1 . A phosphoric acid-free etchant composition, comprising:
 about 40 wt % to about 60 wt % of an organic acid compound;   about 6 wt % to about 12 wt % of a glycol compound;   about 1 wt % to about 10 wt % of nitric acid, sulfuric acid, or hydrochloric acid;   about 1 wt % to about 10 wt % of a nitrate salt compound; and   water, all wt % being based on a total weight of the phosphoric acid-free etchant composition.   
     
     
         2 . The etchant composition as claimed in  claim 1 , further comprising about 1 wt % to about 5 wt % of a chelate compound. 
     
     
         3 . The etchant composition as claimed in  claim 1 , wherein the organic acid compound includes at least three different organic acids. 
     
     
         4 . The etchant composition as claimed in  claim 1 , wherein the organic acid compound includes acetic acid (CH 3 CO 2 H), malic acid (C 4 H 6 O 5 ), citric acid (C 6 H 8 O 7 ), tartaric acid (C 4 H 6 O 6 ), lactic acid (C 3 H 6 O 3 ), methyl sulfonic acid (CH 4 O 3 S), formic acid (CH 2 O 2 ), succinic acid (C 4 H 6 O 4 ), or fumaric acid (C 4 H 4 O 4 ). 
     
     
         5 . The etchant composition as claimed in  claim 1 , wherein the glycol compound includes a compound represented by Chemical Formula 1. 
       
         
           
           
               
               
           
         
         wherein, in Chemical Formula 1, 
         each of Y 1  and Y 2  is H or —OH, at least one of Y 1  and Y 2  being —OH, 
         X is a C 1 -C 10  group, the C 1 -C 10  group including —CR 2 —, —C≡C—, —CF 2 O—, —CR═CR—, —CO—, —O—, —CO—O—, —O—CO—, or —O—CO—O— in such a way that oxygen atoms are not directly connected to each other, R being —H, a halogen, or —OH, and 
         m is a natural number of 1 to 20. 
       
     
     
         6 . The etchant composition as claimed in  claim 1 , wherein the nitrate salt compound includes aluminum nitrate (Al(NO 3 ) 3 ), ammonium nitrate (NH 4 NO 3 ), calcium nitrate (Ca(NO 3 ) 2 ), copper nitrate (Cu(NO 3 ) 2 ), indium nitrate (In(NO 3 ) 3 ), iron nitrate (Fe(NO 3 ) 3 ), lithium nitrate (LiNO 3 ), potassium nitrate (KNO 3 ), silver nitrate (AgNO 3 ), or sodium nitrate (NaNO 3 ). 
     
     
         7 . The etchant composition as claimed in  claim 2 , wherein the chelate compound includes citric acid (C 6 H 8 O 7 ), diethanolamine (C 4 H 11 NO 2 ), diethylenetriamine pentaacetic acid (C 14 H 23 N 3 O 10 ), ethylenediaminetetraacetic acid (C 10 H 16 N 2 O 8 ), ethylenediamine (C 2 H 8 N 2 ), iminodiacetic acid (C 4 H 7 NO 4 ), ethanolamine (C 2 H 7 NO), or malonic acid (C 3 H 4 O 4 ). 
     
     
         8 . The etchant composition as claimed in  claim 1 , wherein the phosphoric acid-free etchant composition is formulated to etch a thin film including a single layer made of silver or a silver alloy. 
     
     
         9 . The etchant composition as claimed in  claim 8 , wherein:
 the thin film further includes an indium oxide layer, and   the indium oxide layer includes indium tin oxide (ITO), indium zinc oxide (IZO), indium tin zinc oxide (ITZO), or indium gallium zinc oxide (IGZO).   
     
     
         10 . A method of forming a wiring, the method comprising:
 forming a thin film on a substrate; and   etching the thin film in a predetermined wiring shape using the etchant composition,   wherein the etchant composition is a phosphoric acid-free etchant composition that includes:   about 40 wt % to about 60 wt % of an organic acid compound;   about 6 wt % to about 12 wt % of a glycol compound;   about 1 wt % to about 10 wt % of nitric acid, sulfuric acid, or hydrochloric acid;   about 1 wt % to about 10 wt % of a nitrate salt compound; and   water, all wt % being based on a total weight of the phosphoric acid-free etchant composition.   
     
     
         11 . The method as claimed in  claim 10 , wherein the thin film includes a single layer made of silver or a silver alloy. 
     
     
         12 . The method as claimed in  claim 11 , wherein
 the thin film further includes a indium oxide layer, and   the indium oxide layer includes indium tin oxide (ITO), indium zinc oxide (IZO), indium tin zinc oxide (ITZO), or indium gallium zinc oxide (IGZO).   
     
     
         13 . The method as claimed in  claim 11 , wherein the thin film includes an indium oxide layer/silver, an indium oxide layer/a silver alloy, an indium oxide layer/silver/an indium oxide layer, or an indium oxide layer/a silver alloy/an indium oxide layer. 
     
     
         14 . The method as claimed in  claim 11 , wherein the silver alloy includes silver (Ag) and nickel (Ni), copper (Cu), zinc (Zn), manganese (Mn), chromium (Cr), tin (Sn), palladium (Pd), neodymium (Nd), niobium (Nb), molybdenum (Mo), magnesium (Mg), tungsten (W), protactinium (Pa), aluminum (Al), or titanium (Ti). 
     
     
         15 . The method as claimed in  claim 10 , wherein the substrate is tilted to have an angle of about 0 to about 60 degrees during the etching of the thin film. 
     
     
         16 . The method as claimed in  claim 10 , wherein the organic acid compound includes at least three different organic acids. 
     
     
         17 . The method as claimed in  claim 10 , wherein the organic acid compound includes acetic acid (CH 3 CO 2 H), malic acid (C 4 H 6 O 5 ), citric acid (C 6 H 8 O 7 ), tartaric acid (C 4 H 6 O 6 ), lactic acid (C 3 H 6 O 3 ), methyl sulfonic acid (CH 4 O 3 S), formic acid (CH 2 O 2 ), succinic acid (C 4 H 6 O 4 ), or fumaric acid (C 4 H 4 O 4 ). 
     
     
         18 . The method as claimed in  claim 10 , further comprising forming a mask on the thin film according to a shape of the wiring, prior to etching the thin film. 
     
     
         19 . The method as claimed in  claim 10 , wherein:
 the thin film includes a first layer made of silver or a silver alloy; and at least one second layer provided on or under the first layer and including indium oxide,   the method further includes etching the second layer,   the phosphoric acid-free etchant composition etches the first layer, and   an etchant for etching the second layer is different from the phosphoric acid-free etchant composition.   
     
     
         20 . The method as claimed in  claim 19 , wherein the etchant for etching the second layer does not etch the first layer and the phosphoric acid-free etchant composition does not etch the second layer.