Apparatus and method for electrolytically depositing a metal on a workpiece

A method of forming copper interconnect structures in submicron micro-recesses on a workpiece having a barrier layer conforming to the micro-recesses and a copper seed layer over the barrier layer, the seed layer having a thickness of 50 Å to 500 Å, and the seed layer being a non-continuous layer that has voids through which areas of the barrier layer are exposed, the method comprising:

• adhering additional copper to the exposed areas of the barrier layer to fill the voids within the non-continuous seed layer by contacting the workpiece with a first solution containing copper to form a conformal seed layer that covers substantially all of the barrier layer;
• and
• filling the micro-recesses by electroplating copper over the conformal seed layer in a second solution containing copper, wherein the first solution is different from the second solution.

A method of forming copper interconnect structures in submicron micro-recesses on a workpiece having a barrier layer conforming to the micro-recesses and a copper seed layer over the barrier layer, the seed layer having a thickness of 50 Å to 500 Å, and the seed layer being a non-continuous layer that has voids through which areas of the barrier layer are exposed, the method comprising:

• adhering additional copper to the exposed areas of the barrier layer to fill the voids within the non-continuous seed layer and reducing copper oxide on the non-continuous seed layer to metallic copper by contacting the workpiece with a first solution containing copper to form a conformal metallic copper seed layer that covers substantially all of the barrier layer;
• and
• filling the micro-recesses by electroplating copper over the conformal seed layer in a second solution containing copper, wherein the first solution is different from the second solution.

A method of forming copper interconnect structures in submicron micro-recesses having a width less than 0.5 μm on a workpiece including a barrier layer conforming to the micro-recesses and a copper seed layer over the barrier layer, the seed layer having a thickness of 50 Å to 500 Å, and the seed layer being a non-continuous layer that has voids through which areas of the barrier layer are exposed, the method comprising:

• adhering additional copper to the exposed areas of the barrier layer to fill the voids within the non-continuous seed layer by contacting the workpiece with a first solution containing copper to form a conformal seed layer that covers substantially all of the barrier layer;
• and
• filling the micro-recesses by electroplating copper over the conformal seed layer in a second solution containing copper, wherein the first solution is different from the second solution.