Electrolyte and process for depositing a matt metal layer

Abstract

An electrolytic composition for the deposition of a matt metal layer onto a substrate and deposition process where the composition comprises a source of metal from the group consisting of Cr, Mn, Fe, Co, Ni, Cu, Zn, Ru, Rh, Pd, Ag, In, Sn, Sb, Re, Pt, Au, Bi, and combinations thereof; a substituted or unsubstituted polyalkylene oxide or its derivative as an emulsion and/or dispersion former; and a compound comprising fluorated or perfluorated hydrophobic chains or which is a polyalkylene oxide substituted quaternary ammonium compound as wetting agent; wherein the electrolytic composition forms a microemulsion and/or dispersion.

1 . An electrolytic composition for the deposition of a Ni-free matt metal layer onto a substrate, the composition comprising:
 a) a source of metal selected from the group consisting of Cr, Mn, Fe, Co, Cu, Zn, Ru, Rh, Pd, Ag, In, Sn, Sb, Re, Pt, Au, and Bi and combinations thereof;   b) an emulsion and/or dispersion former comprising a substituted or unsubstituted polyalkylene oxide or its derivative;   c) a wetting agent selected from the group consisting of a compound comprising i) a fluorinated or perfluorinated hydrophobic chain, OR ii) a polyalkylene oxide substituted quaternary ammonium compound, OR iii) a combination thereof; and   d) polytetrafluorethylene particles with an average particle diameter of about 10 nm to about 1000 nm;   wherein the electrolytic composition forms a microemulsion and/or dispersion.   
     
     
         2 . The electrolyte composition of  claim 1  wherein the source of metal is Cu. 
     
     
         3 . The electrolyte composition of  claim 1  wherein the source of metal is Sn and Co. 
     
     
         4 . The electrolyte composition of  claim 1  wherein the source of metal is Ag. 
     
     
         5 . The electrolyte composition of  claim 1  wherein the emulsion and/or dispersion former is selected from the group consisting of a substituted or unsubstituted polyethylene oxide, polypropylene oxide, polypropylene-polyethylene oxide block copolymer, and a mixture thereof. 
     
     
         6 . The electrolyte composition of  claim 5  wherein the emulsion and/or dispersion former has an average molecular weight >200 g/mol. 
     
     
         7 . The electrolyte composition of  claim 5  wherein the emulsion and/or dispersion former compound has a high percentage of hydrophobic structures and a molecular weight between about 200 and about 2000 g/mol. 
     
     
         8 . The electrolyte composition of  claim 5  wherein the emulsion and/or dispersion former has a high percentage of hydrophilic structures and a molecular weight >4000 g/mol. 
     
     
         9 . The electrolyte composition of  claim 1  wherein the fluorated or perfluorated wetting agent has the general formula
   R f CH 2 CH 2 O(CH 2 CH 2 O) x H 
 with R f =F(CF 2 CF 2 ) n , wherein X=6 to 15 and n=2 to 10. 
 
     
     
         10 . The electrolyte composition of  claim 9  wherein the average molecular weight of the wetting agent is between about 550 and about 1000 g/mol. 
     
     
         11 . The electrolyte composition of  claim 9  wherein the average molecular weight of the wetting agent is between about 700 and about 1000 g/mol. 
     
     
         12 . The electrolyte composition of  claim 1  wherein the wetting agent is a polyalkylene oxide-substituted quaternary ammonium compound which has the following general formula 
       
         
           
           
               
               
           
         
       
       wherein at least one radical R 1 , R 2 , R 3  or R 4  is a polyalkylene oxide substituent and the remaining radicals independently are same or different straight-chained or branched saturated or unsaturated C 1  to C 18  alkyl chains and X −  is a halide, a sulfate anion or anion of a C 1  to C 6  carbonic acid. 
     
     
         13 . The electrolyte composition of  claim 12  wherein R 1  and R 2  are a C 8  to C 12  alkyl side chain, R 3  is a C 1  to C 3  alkyl side chain, R 4  corresponds to the general formula [CH 2 —CH 2 —O] n H with n=1 to 5, and X −  is the anion of a C 2  to C 4  carbonic acid. 
     
     
         14 . The electrolyte composition of  claim 12  wherein R 1  and R 2  are a C 10  alkyl side chain, R 3  is a C 1  alkyl side chain, R 4  corresponds to the general formula [CH 2 —CH 2 —O] n H with n=1 to 5, and X −  is the anion of a C 2  to C 4  carbonic acid. 
     
     
         15 . The electrolyte composition of  claim 12  wherein the average molecular weight of the wetting agent is between about 200 and about 1000 g/mol. 
     
     
         16 . The electrolyte composition of  claim 12  wherein the average molecular weight of the wetting agent is between about 400 and about 500 g/mol. 
     
     
         17 . The electrolyte composition of  claim 1  further comprising polytetrafluorethylene particles with an average particle diameter of about 10 to about 1000 nm. 
     
     
         18 . The electrolyte composition of  claim 1  further comprising polytetrafluorethylene particles with an average particle diameter of about 100 to about 300 nm. 
     
     
         19 . The electrolyte composition of  claim 18  wherein the electrolyte contains the polytetrafluorethylene particles at a concentration of 0.1 to 1000 mg/l. 
     
     
         20 . The electrolyte composition of  claim 18  wherein the electrolyte contains the polytetrafluorethylene particles at a concentration of about 0.5 to 5 mg/l. 
     
     
         21 . A process for the electrolytic deposition of a matt metal layer on a substrate comprising immersing the substrate in the electrolytic composition of  claim 1  and applying a current between the substrate and the counter electrode.