Temperature control of chemical mechanical polishing
A chemical mechanical polishing apparatus includes a platen to hold a polishing pad, a carrier to hold a substrate against a polishing surface of the polishing pad during a polishing process, a dispenser to supply a polishing liquid to the polishing surface, and a temperature control system including a body configured to contact the polishing surface or the polishing liquid on the polishing surface. The body supports a thermal control module positioned over the polishing pad.
1. A chemical mechanical polishing apparatus comprising:
a platen to hold a polishing pad;
a carrier to hold a substrate against a polishing surface of the polishing pad during a polishing process;
a dispenser to supply a polishing liquid to the polishing surface;
a temperature control system including a body configured to contact the polishing surface or the polishing liquid on the polishing surface, the body supporting a thermal control module positioned over the polishing pad, wherein the thermal control module comprises a stack including a thermoelectric heat pump and a heat exchanger; and
an actuator to adjust a vertical position of the body relative to the polishing pad.
2. The apparatus of claim 1 , wherein the body comprises a linear arm of substantially uniform width.
3. The apparatus of claim 1 , wherein the body comprises a wedge-shaped arm.
4. The apparatus of claim 1 , wherein at least a portion of the body that contacts the polishing pad or polishing liquid comprises a ceramic.
5. The apparatus of claim 4 , wherein the body is ceramic.
6. The apparatus of claim 4 , wherein the portion of the body comprises a coating of ceramic on another material.
7. The apparatus of claim 1 , wherein at least a portion of the body that contacts the polishing pad or polishing liquid comprises silicon carbide, silicon nitride aluminum nitride, diamond or diamond-like carbon.
8. The apparatus of claim 1 , wherein the heat exchanger is above the thermoelectric heat pump.
9. The apparatus of claim 8 , comprising a controller configured to control a current to the thermoelectric heat pump to cause the heat pump to drive heat to or from the polishing pad, and to control a temperature or flow rate of fluid passing through the heat exchanger to cause the heat exchanger to raise or lower a temperature of a top surface of the thermoelectric heat pump.
10. The apparatus of claim 9 , further comprising a polishing liquid supply port to distribute polishing liquid onto the polishing pad, and wherein the body is positioned to provide a barrier to flow of the polishing liquid.
11. The apparatus of claim 1 , wherein a portion of the body is positioned between the thermal control module and the polishing pad or the polishing liquid.
12. A chemical mechanical polishing apparatus comprising:
a platen to hold a polishing pad;
a carrier to hold a substrate against a polishing surface of the polishing pad during a polishing process;
a temperature control system including a plurality of thermal control modules positioned above the polishing pad, each thermal control module including a stack including a thermoelectric heat pump and a heat exchanger having a passage to receive a fluid and exchange heat between the polishing pad and the fluid, the temperature control system further including a plurality of fluid circulators to supply fluid at two different temperatures, and a plurality of valves to selectively fluidically couple each of the plurality of fluid circulators to each of the heat exchangers.
13. The apparatus of claim 12 , wherein the heat exchanger is above the thermoelectric heat pump.
14. The apparatus of claim 12 , comprising a controller configured to control a current to the thermoelectric heat pump to cause the heat pump to drive heat to or from the polishing pad, and to control a temperature or flow rate of fluid passing through the heat exchanger to cause the heat exchanger to raise or lower a temperature of a top surface of the thermoelectric heat pump.
15. The apparatus of claim 12 , wherein the temperature control system includes a body configured to contact the polishing surface or [[the]] a polishing liquid on the polishing surface, wherein the body supports the thermal control modules over the polishing pad.
16. The apparatus of claim 15 , further comprising an actuator to adjust a vertical position of the body relative to the polishing pad.
17. The apparatus of claim 15 , further comprising a polishing liquid supply port to distribute polishing liquid onto the polishing pad, and wherein the body is positioned to provide a barrier to flow of the polishing liquid.