Acid aqueous electrolyte, used for coating electronic components with a tin-copper alloy, comprises alkyl sulfonic acids and/or alkanol sulfonic acids, soluble tin (II) salts, soluble copper (II) salts, and organic sulfur compounds

摘要

An acid aqueous electrolyte comprises at least one alkyl sulfonic acids and/or alkanol sulfonic acids; at least one soluble tin (II) salts; at least one soluble copper (II) salts; and at least one organic sulfur compounds having thioether and/or ether functions of general formula: -R-Z-R'- (where, Z = S or O; and R and R' = the same or different non-aromatic organic residues). An Independent claim is also included for a process for electrolytically coating substrates with a tin-copper alloy using the above electrolyte.