Stable plating performance in copper electrochemical plating
AssigneeTaiwan Semiconductor Manufacturing Company, Ltd.
InventorsChen-Ming Huang, Li-Chuen Cheng, Hung-Jen Lin, Chih-Chen Ku, San-Sun Yang
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Abstract
A real-time and in-line process control system maintains stable plating performance in copper electrochemical plating IC devices by using a real time, on-line programmable controller. Two or more valves to direct the flow of the electrolyte from the electroplating cell back to the reservoir connect an alternative carbon-filter as well as a mirco-filter. The programmable controller controls the operation of at least two in-line valves to direct the flow of the electrolyte within the system.
Claims9
A system for maintaining stable plating performance in copper electrochemical plating IC devices comprising:
- an electrolyte tank containing the copper-plating electrolyte;
- an electroplating cell receiving said copper plating electrolyte from said electrolyte tank, said cell adapted to receive the IC devices to be plated;
- a micro-filter receiving said copper plating electrolyte from said cell;
- a first valve interposed said cell and said micro-filter, said first valve is operable to control the flow of said copper plating electrolyte to said micro-filter;
- a carbon-filter coupled to said cell for receiving said copper plating electrolyte from said cell, said carbon-filter for removing byproducts of additives from said electrolyte, said electrolyte flowing to said micro-filter from said carbon-filter;
- a second valve interposed said cell and said carbon-filter, said second valve operable to control the flow of said copper plating electrolyte from said cell to said carbon-filter;
- a programmable controller having a memory, input circuits, valve control circuits, output circuits, and analysis control circuits, said controller operable for controlling said first and second valves in such a manner that said copper plating electrolyte flows from said cell to one of said filters;
- and
- an algorithm stored in said memory of said programmable controller and responsive to several inputs measuring a plating process for opening one of said valves and closing the other of said valves for controlling said flow of the copper plating electrolyte.
A method for controlling the stability of the electrolyte in a copper electrochemical plating of IC devices comprising the steps of:
- supplying a tank of copper plating electrolyte;
- flowing the copper-plating electrolyte from the electrolyte tank, to an electroplating cell;
- placing the IC devices to be plated in the electroplating cell;
- filtering through a micro-filter the copper-plating electrolyte flowing from the cell;
- controlling through a first valve the flow of the copper-plating electrolyte to the micro-filter;
- controlling through a second valve the flow of the copper-plating electrolyte from the cell;
- removing additives from the electrolyte from the cell through a carbon-filter coupled to the cell and the second valve, said electrolyte flowing to said micro-filter from said carbon-filter;
- controlling by a programmable controller the first and second valves in such a manner that the copper plating electrolyte flows from the cell to only one of the filters;
- and
- storing in the memory of the programmable controller an algorithm responsive to several inputs measuring a plating process for opening one of the valves and closing the other of the valves for controlling the flow of the copper-plating electrolyte.
Dependencies are inferred from the claim text.