Method and apparatus for low-temperature annealing of metallization microstructures in the production of a microelectronic device

A method of treating a workpiece having a base having a surface, a dielectric layer carried on the surface of the base, and recessed sub-micron structures formed in the dielectric layer, comprising:

• depositing a conductive seed layer exterior to the dielectric layer and in the recessed sub-micron structures;
• contacting the seed layer with a copper-containing electroplating solution;
• applying electroplating power to the seed layer to electrolytically deposit copper metal from the electroplating solution to substantially fill the recessed sub-micron structures and to deposit excess copper metal which extends beyond an exterior surface of the dielectric layer;
• then
• subjecting the electroplated workpiece to an elevated temperature annealing process comprising establishing a temperature gradient in which the temperature decreases in a direction moving outwardly from the base toward the dielectric layer, the annealing process having a maximum gradient temperature which is no greater than about 250 degrees Celsius.

A method of treating a microelectronic workpiece having a base having a surface including a sub-micron recessed microstructure, comprising:

• contacting the surface of the workpiece with a copper-containing electroplating solution;
• applying electroplating power at a first power level for a first period of time, then applying electroplating power at a higher second power level for a time sufficient to substantially fill the recessed sub-micron structures with electroplated copper metal and to deposit excess copper metal above the sub-micron recessed microstructures;
• then
• subjecting the electroplated workpiece to an elevated temperature annealing process comprising establishing a temperature gradient through the electroplated copper metal in which the temperature decreases in a direction moving outwardly from the base toward the workpiece surface, the annealing process having a maximum gradient temperature which is no greater than about 250 degrees Celsius.

A method of treating a microelectronic workpiece having a base having a surface including a sub-micron recessed microstructure, comprising:

• contacting the surface of the workpiece with a copper-containing electroplating solution;
• applying electroplating power to the workpiece in a pulsed waveform having a frequency of between about 1 and 1000 Hz to substantially fill the recessed sub-micron structures with electroplated copper metal and to deposit excess copper metal above the sub-micron recessed microstructures;
• then
• subjecting the electroplated workpiece to an elevated temperature annealing process comprising establishing a temperature gradient through the electroplated copper in which the temperature decreases in a direction moving outwardly from the base toward the surface of the workpiece, the temperature gradient having a maximum gradient temperature which is no greater than about 250 degrees Celsius.

A method of processing a microelectronic workpiece having a surface including a sub-micron recessed microstructure and a conductive seed layer in the sub-micron recessed microstructure, comprising:

• electroplating copper at an electroplating station to substantially fill the recessed microstructure and to deposit excess copper which extends above the sub-micron recessed microstructure;
• robotically transferring the workpiece from the electroplating station for further processing;
• removing the excess copper as one of the further processes;
• and
• thereafter, robotically transferring the workpiece to a thermal processing station to thermally treat the electroplated copper by establishing a temperature gradient in the electroplated copper having a maximum temperature of about 60 degrees Celsius to about 100 degrees Celsius for no longer than 15 minutes, thereby reducing resistivity of the copper and reducing voids which may be present in the copper.

A method of treating a microelectronic workpiece having a base having a surface including a sub-micron recessed microstructure, comprising:

• contacting the surface of the workpiece with a copper-containing electroplating solution;
• applying electroplating power at a first power level for a first period of time, then applying electroplating power at a higher second power level for a time sufficient to substantially fill the recessed sub-micron structures with electroplated copper metal and to deposit excess copper metal above the sub-micron recessed microstructures;
• then
• subjecting the electroplated workpiece to an elevated temperature annealing process for a time sufficient to reduce resistivity of the electroplated copper metal.

A method of treating a microelectronic workpiece having a base having a surface including a sub-micron recessed microstructure, comprising:

• contacting the surface of the workpiece with a copper-containing electroplating solution;
• applying electroplating power to the workpiece in a pulsed waveform having a frequency of between about 1 and 1000 Hz to substantially fill the recessed sub-micron structures with electroplated copper metal and to deposit excess copper metal above the sub-micron recessed microstructures;
• then
• subjecting the electroplated workpiece to an elevated temperature annealing process for a time sufficient to reduce resistivity of the electroplated copper metal.