Paired dynamic parallel plate capacitively coupled plasmas
Processing chambers with a plurality of processing stations and individual wafer support surfaces are described. The processing stations and wafer support surfaces are arranged so that there is an equal number of processing stations and heaters. An RF generator is connected to a first electrode in a first station and a second electrode in a second station. A bottom RF path is formed by a connection between the a first support surface and a second support surface.
1. A processing chamber comprising:
at least two plasma stations;
a wafer pedestal having a plurality of support surfaces to support individual wafers for processing;
an RF generator connected to a first electrode in a first plasma processing station and a second electrode in a second plasma processing station to form a top RF path; and
a connection between at least two support surfaces of the wafer pedestal to form a bottom RF path,
wherein the first electrode, the connection between the at least two support surfaces of the wafer pedestal and the second electrode form a path for an RF current flow.
2. The processing chamber of claim 1 , wherein the connection between the support surfaces is within the wafer pedestal.
3. The processing chamber of claim 1 , wherein the connection between the support surfaces comprises a coaxial connection.
4. The processing chamber of claim 3 , further comprising a second bottom RF path connecting the support surfaces.
5. The processing chamber of claim 3 , wherein the top RF path is formed with a coaxial cable.
6. The processing chamber of claim 3 , further comprising a tuning element connected to each of the support surfaces.
7. The processing chamber of claim 6 , wherein the tuning element comprises a balun.
8. The processing chamber of claim 6 , wherein the tuning element reduces voltage difference between the support surfaces and a surrounding metal structure forming the processing chamber.
9. The processing chamber of claim 3 , further comprising a dielectric spacer separating the support surfaces.
10. The processing chamber of claim 9 , wherein the dielectric spacer comprises one or more of quartz, ceramic or polytetrafluoroethylene.
11. The processing chamber of claim 1 , further comprising a tuning element connected to each of the support surfaces.
12. The processing chamber of claim 11 , wherein the tuning element comprises a balun.
13. The processing chamber of claim 11 , wherein the bottom RF path is formed without a coaxial cable.
14. A processing chamber comprising: a plurality of processing stations arranged around an interior of the processing chamber, the plurality of processing stations comprising at least two plasma stations; a wafer pedestal having a plurality of heaters to support individual wafers for processing, the number of heaters equal to the number of processing stations; an RF generator connected to a first electrode in a first plasma processing station and a second electrode in a second plasma processing station to form a top RF path; and a connection between a first heater and a second heater of the wafer pedestal to form a bottom RF paths wherein the first electrode, the connection between the first heater and the second heater of the wafer pedestal and the second electrode form a path for an RF current flow.
15. The processing chamber of claim 14 , wherein the connection between the first heater and second heater is within the wafer pedestal.
16. The processing chamber of claim 14 , wherein the connection between the first heater and the second heater comprises a coaxial connection.
17. The processing chamber of claim 16 , further comprising a second bottom RF path connecting the first heater to the second heater.
18. The processing chamber of claim 16 , further comprising a tuning element connected to each of the first heater and second heater.
19. The processing chamber of claim 16 , further comprising a dielectric spacer separating the first heater from the second heater.