Wire bonding to copper

A method for the manufacture of semiconductor integrated circuits comprising the sequential steps of:

• (a) forming a first conductive interconnection layer on a semiconductor substrate,
• (b) depositing a first dielectric layer on said first conductive interconnection layer,
• (c) forming at least one interlevel opening in said first dielectric layer to expose a portion of said first conductive interconnection layer,
• (d) depositing a first barrier layer on said first dielectric layer, and into said interlevel opening,
• (e) depositing a copper layer on said first barrier layer, said copper layer having a thickness sufficient to fill said interlevel opening, and being deposited by the steps of:
• 1. depositing a strike layer of copper on the first barrier layer, and
• 2. electrolytically depositing a copper layer on the strike layer,
• (f) planarizing the surface of the structure produced in step (e) using chemical mechanical polishing leaving a planar copper plug in a planar surface,
• (g) depositing a planar barrier layer on said planar surface and on said copper plug,
• (h) depositing a planar aluminum layer on said planar barrier layer,
• (i) forming a mask on the planar aluminum layer overlying the copper plug leaving portions of the planar aluminum layer exposed,
• (j) etching away the exposed portions of said planar aluminum layer and said planar barrier layer to leave a planar barrier layer pad and a planar aluminum layer pad on said copper plug, and
• (k) thermocompression bonding a conductive wire to said planar aluminum layer pad.