Copper electroplating solutions and methods of making and using them

Abstract

A method of preparing a compound useful as a brightener in aqueous copper electroplating solutions comprising reacting a compound of the following formula: ##STR1## with a compound of the formula: HS--R.sub.2 --Z.sub.n wherein: R.sub.1 and R.sub.2 each is an alkyl containing from 2 to 8 carbon atoms, an aryl, an alkylaryl, an arylalkyl or a heterocyclic group containing at least one nitrogen atom in its ring; X, Y and Z each is hydrogen or a water-solubilizing group; and n is an integer of from 1 to 4; provided that: when R.sub.1 is a heterocyclic group, X, Y and Z are hydrogen and R.sub.2 is an alkyl containing from 2 to 8 carbon atoms, an aryl, an alkylaryl or an arylalkyl; when R.sub.2 is a heterocyclic group, X, Y and Z are hydrogen and R.sub.1 is an alkyl containing from 2 to 8 carbon atoms, an aryl, an alkylaryl or an arylalkyl; when X or Y is a water-solubilizing group, R.sub.2 is an alkyl containing from 2 to 8 carbon atoms, an aryl, an alkylaryl or an arylalkyl and Z is hydrogen; when Z is a water-solubilizing group, R.sub.1 is an alkyl containing from 2 to 8 carbon atoms, an aryl, an alkylaryl or an arylalkyl and X and Y are hydrogen; and when X and Y are both water-solubilizing groups they may be the same or different water-solubilizing groups. The invention also comprises aqueous acidic copper electroplating solutions containing the brightener and methods of making and using such solutions.

Dependencies are inferred from the claim text.