Electrostatic chuck and methods of use thereof
An electrostatic chuck and method of use thereof is provided herein. In some embodiments, an electrostatic chuck may include a disk having a first side to support a substrate thereon and a second side, opposing the first side, to provide an interface to selectively couple the disk to a thermal control plate, a first electrode disposed within the disk proximate the first side to electrostatically couple the substrate to the disk and a second electrode disposed within the disk proximate the opposing side of the disk to electrostatically couple the disk to the thermal control plate. In some embodiments, the second electrode may also be configured to heat the disk.
1. An electrostatic chuck, comprising:
a disk having a first side to support a substrate thereon and a second side, opposing the first side, to provide an interface to selectively couple the disk to a thermal control plate, a first electrode disposed within the disk proximate the first side to electrostatically couple the substrate to the disk and a second electrode disposed within the disk proximate the second side to electrostatically couple the disk to the thermal control plate.
2. The electrostatic chuck of claim 1 , further wherein the second electrode is further configured to heat the disk.
3. The electrostatic chuck of claim 1 , further comprising:
at least one groove formed in the second side of the disk or in the thermal control plate to flow a heat transfer fluid between the disk and the thermal control plate.
4. The electrostatic chuck of claim 3 , wherein the heat transfer fluid comprises argon or helium gas.
5. The electrostatic chuck of claim 1 , wherein the disk further comprises at least one groove formed in the first side to flow a heat transfer fluid between the first side of the disk and the substrate.
6. The electrostatic chuck of claim 1 , wherein the disk further comprises:
a base;
a first layer of dielectric material disposed atop the base, wherein the first electrode and second electrode are disposed atop the first layer of dielectric material; and
a second layer of dielectric material disposed atop the first electrode and second electrode.
7. The electrostatic chuck of claim 6 , wherein the base comprises graphite, pyrolytic boron nitride, or silicon.
8. The electrostatic chuck of claim 6 , wherein the first and second layer of dielectric material comprises pyrolytic boron nitride.
9. The electrostatic chuck of claim 1 , wherein the disk further comprises:
a dielectric base, wherein the first electrode and second electrode are disposed atop the dielectric base; and
a layer of dielectric material disposed atop the first electrode and second electrode.
10. The electrostatic chuck of claim 1 , further comprising:
a thermal control plate disposed beneath the second side of the disk and selectively coupleable to the disk via an electrostatic attraction when power is provided to the second electrode.
11. The electrostatic chuck of claim 10 , further comprising:
a support shaft to support the thermal control plate, wherein the shaft comprises a conduit to provide at least one of heat transfer fluids, process gases, AC power, DC power, or RF power to the electrostatic chuck.
12. The electrostatic chuck of claim 1 , wherein the disk has a coefficient of thermal expansion that is substantially equal to a coefficient of thermal expansion of the substrate.
13. The electrostatic chuck of claim 1 , wherein the disk has a thickness of about three times greater than a thickness of the substrate.
14. The electrostatic chuck of claim 1 , wherein the disk has a thickness of about 1.0 to about 2.5 mm.
15. A method of processing a substrate, comprising:
placing an electrostatic chuck on a thermal control plate, the electrostatic chuck comprising a disk having a first side to support a substrate thereon and a second side, opposing the first side, providing an interface with the thermal control plate, wherein a first electrode is disposed within the disk proximate the first side to electrostatically couple the substrate to the disk, and wherein a second electrode is disposed within the disk proximate the second side to selectively electrostatically couple the disk to the thermal control plate;
clamping a substrate to the first side of the disk by providing power to the first electrode; and
selectively increasing or decreasing a rate of thermal conductivity through the interface between the second side of the disk and the thermal control plate to control the rate of heat transfer between the disk and the thermal control plate.
16. The method of claim 15 , further comprising:
decreasing the rate of thermal conductivity through the interface when heating the substrate.
17. The method of claim 16 , wherein decreasing the rate of thermal conductivity through the interface comprises at least one of:
decreasing a pressure of a gas provided to the interface via one or more grooves disposed between the disk and the thermal control plate; or
decreasing a chucking voltage provided to the second electrode to electrostatically clamp the disk to the thermal control plate.
18. The method of claim 15 , further comprising:
increasing the rate of thermal conductivity through the interface when cooling the substrate.
19. The method of claim 18 , wherein increasing the rate of thermal conductivity through the interface comprises at least one of:
increasing a pressure of a gas provided to the interface via one or more grooves disposed between the disk and the thermal control plate; or
increasing a chucking voltage provided to the second electrode to electrostatically clamp the disk to the thermal control plate.
20. The method of claim 15 , further comprising at least one of:
providing an AC current to the second electrode to heat the disk and the substrate; or
providing an AC current to the first electrode to heat the disk and the substrate.