Amine-containing bath for electroplating palladium

Claim 1

In an aqueous bath for producing an electrodeposit of palladium, the combination, expressed as gram moles per liter, comprising: 0.01 to 0.25 of palladium ion; 0.15 to 1.5 of a soluble electrolyte; and 0.35 to 2.1 of an amine complexing agent, said agent consisting of at least one aliphatic amine compound having the structural formula: R 1 --NH--R 2 , wherein R 1 and R 2 are the same or different and are selected from the calss consisting of the hydrogen atom, methyl, ethyl and hydroxyethyl groups, with the proviso that R 1 and R 2 are not both hydrogen, and at least one alicyclic amine compound selected from the group consisting of pyrrolidine, 2-methyl pyrolidine, 3-methyl pyrrolidine and piperazine, said aliphatic amine and alicyclic amine compounds being present in a molar ratio of about 0.5:1 to 1.5:1; and water to volume, said bath having a pH of about 6.0 to 10.0 and being substantially devoid of free ammonia.

Claim 14

A method of electroplating a workpiece with palladium including the steps: (a) preparing an aqueous bath comprising the following ingredients, expressed in gram moles per liter: 0.01 to 0.25 of palladium ion; 0.15 to 1.5 of a soluble electrolyte; and 0.35 to 2.1 of an amine complexing agent, said agent consisting of at least one aliphatic amine compound having the structural formual R 1 --NH--R 2 , wherein R 1 and R 2 are the same or different and are selected from the class consisting of the hydrogen ato, methyl, ethyl and hydroxyethyl groups, with the proviso that R 1 and R 2 are not both hydrogen and at least one alicyclic amine compound selected from the group consisting of pyrrolidine, 2-methyl pyrrolidine, 3-methyl pyrrolidine and piperazine, said aliphatic amine and alicyclic amine compounds being present in a mole ratio of about 0.5:1 to 1.5:1; and water to volume, said bath having a pH of about 6.0 to 10.0 and being substantially devoid of free ammonia; (b) immersing a workpiece having an electrically conductive surface in said aqueous bath; (c) maintaining the temperature of said bath of about 32° to 60° Centigrade; (d) applying an electrical potential across said workpiece and an anode to provide a current density of about 0.05 to 25 amperes per square decimeter at said workpiece to effect electroplating of the desired thickness for the deposit; and (e) removing the electroplated workpiece from said bath.

Claim 15

A method of electroplating a workpiece with palladium including the steps: (a) preparing an aqueous bath comprising the following ingredients, expressed in gram moles per liter: 0.01 to 0.25 of palladium ion; 0.15 to 1.5 of a soluble electrolyte; and 0.35 to 2.1 of an amine complexing agent, said agent consisting of at least one aliphatic amine compound having the structural formual R 1 --NH--R 2 , wherein R 1 and R 2 are the same or different and are selected from the class consisting of the hydrogen ato, methyl, ethyl and hydroxyethyl groups, with the proviso that R 1 and R 2 are not both hydrogen and at least one alicyclic amine compound selected from the group consisting of pyrrolidine, 2-methyl pyrrolidine, 3-methyl pyrrolidine and piperazine, said aliphatic amine and alicyclic amine compounds being present in a mole ratio of about 0.5:1 to 1.5:1; and water to volume, said bath having a pH of about 6.0 to 10.0 and being substantially devoid of free ammonia; (b) immersing a workpiece having an electrically conductive surface in said aqueous bath; (c) maintaining the temperature of said bath of about 32° to 60° Centigrade; (d) applying an electrical potential across said workpiece and an anode to provide a current density of about 0.05 to 25 amperes per square decimeter at said workpiece to effect electroplating of the desired thickness for the deposit; and (e) removing the electroplated workpiece from said bath.