Method for electroless plating a contact pad

A method of forming a conductive passivation layer for a contact pad in an integrated circuit formed on a substrate, the contact pad comprising a conductive layer exposed through a window in a surrounding insulating layer, the method comprising:

• providing a container having first, second and third liquid phases separated from one another, the first phase contacting the second phase and the second phase contacting the third phase;
• immersing the substrate in the first phase wherein the conductive layer is cleaned;
• transferring the substrate from the first phase directly to the second phase, wherein a protective layer is selectively formed on the insulating layer;
• transferring the substrate from the second phase directly to the third phase, wherein a monomer layer is selectively formed on the cleaned conductive layer;
• and
• polymerizing the monomer layer.

A method for electroless plating a conductive polymer on a metal surface of a workpiece, comprising:

• immersing the workpiece in a container holding a plurality of solutions, wherein each of said plurality of solutions is in contact with at least one other of said plurality of solutions, thereby allowing direct transfer of said workpiece between said plurality of solutions in said container;
• exposing the metal surface to an oxide cleaning solution within the container;
• preferentially forming a layer comprising a conducting monomer after exposing the metal surface to an oxide cleaning solution and prior to removing the workpiece from the container;
• and
• polymerizing said conducting monomer layer.

A method of forming a conductive passivation layer for a contact pad in a circuit formed on a substrate, the contact pad comprising a conductive layer exposed through a window in a surrounding insulating layer, the method comprising:

• providing a container having first, second and third liquid phases separated from one another;
• immersing the substrate in the first phase wherein the conductive layer is cleaned;
• transferring the substrate from the first phase directly to the second phase without exposing the substrate to any intermediate phase, wherein a protective layer is selectively formed on the insulating layer;
• transferring the substrate from the second phase directly to the third phase without exposing the substrate to any intermediate phase, wherein a monomer layer is selectively formed on the cleaned conductive layer;
• and
• polymerizing the monomer layer, wherein the first phase comprises an oxide etch bath and the protective layer comprises a hydrophobic exposed surface.