Substrate pedestal module including metallized ceramic tubes for RF and gas delivery
A semiconductor substrate processing apparatus includes a vacuum chamber having a processing zone in which a semiconductor substrate may be processed, a process gas source in fluid communication with the vacuum chamber for supplying a process gas into the vacuum chamber, a showerhead module through which process gas from the process gas source is supplied to the processing zone of the vacuum chamber, and a substrate pedestal module. The substrate pedestal module includes a pedestal made of ceramic material having an upper surface configured to support a semiconductor substrate thereon during processing, a stem made of ceramic material, and a backside gas tube made of metallized ceramic material that is located in an interior of the stem. The metallized ceramic tube can be used to deliver backside gas to the substrate and supply RF power to an embedded electrode in the pedestal.
1. A semiconductor substrate processing apparatus for processing semiconductor substrates, comprising:
a vacuum chamber including a processing zone in which a semiconductor substrate may be processed;
a process gas source in fluid communication with the vacuum chamber for supplying a process gas into the vacuum chamber;
a showerhead module through which process gas from the process gas source is supplied to the processing zone of the vacuum chamber; and
a substrate pedestal module including a platen made of ceramic material having an upper surface configured to support a semiconductor substrate thereon during processing; a stem made of ceramic material having an upper stem flange that supports the platen; and a backside gas tube made of metallized ceramic material that is located in an interior of the stem, the backside gas tube configured to supply backside gas to the upper surface of the platen and supply power to an electrode embedded in the platen.
2. The semiconductor substrate processing apparatus of claim 1 , wherein the electrode is an electrostatic clamping electrode.
3. The semiconductor substrate processing apparatus of claim 1 , wherein the electrode is an RF electrode.
4. The semiconductor substrate processing apparatus of claim 1 , wherein the platen includes one or more resistance heaters embedded therein and the heaters are electrically connected to metallized ceramic feed rods or metal feed rods located inside the stem.
5. The semiconductor substrate processing apparatus of claim 1 , wherein the substrate pedestal module further includes a thermocouple configured to measure temperature of the platen, the thermocouple located inside a ceramic tube attached to an underside of the platen at a location inside the stem.
6. The semiconductor substrate processing apparatus of claim 1 , wherein the backside gas tube, the platen and the stem are formed of aluminum nitride.
7. The semiconductor substrate processing apparatus of claim 1 , wherein the backside gas tube is centrally located in the interior of the stem.
8. The semiconductor substrate processing apparatus of claim 1 , wherein the platen includes an outer RF electrode embedded therein and inner electrostatic clamping (ESC) electrodes embedded therein, the inner ESC electrodes coplanar with the outer RF electrode, the outer RF electrode electrically connected to a metallized ceramic power feed rod inside the stem, and each of the inner ESC electrodes electrically connected to a pair of metallized ceramic feed rods inside the stem.
9. The semiconductor substrate processing apparatus of claim 1 , wherein the metallized ceramic tube is connected to the electrode by a stress relief connection, the stress relief connection configured to change shape to accommodate differential thermal expansion between the metallized ceramic tube and the electrode.
10. A semiconductor substrate support module useful for processing semiconductor substrates in a vacuum chamber including a processing zone in which a semiconductor substrate may be processed, the substrate support module comprising:
a platen made of ceramic material having an upper surface configured to support a semiconductor substrate thereon during processing;
a stem made of ceramic material having an upper stem flange that supports the platen; and
at least one backside gas tube made of metallized ceramic material that is located in an interior of the stem, the backside gas tube configured to supply backside gas to the upper surface of the platen and supply power to an electrode embedded in the platen.
11. The substrate support module of claim 10 , wherein the electrode is an electrostatic clamping electrode.
12. The substrate support module of claim 10 , wherein the electrode is an RF electrode.
13. The substrate support module of claim 10 , wherein the platen includes one or more resistance heaters embedded therein and the heaters are electrically connected to metallized ceramic feed rods or metal feed rods located inside the stem.
14. The substrate support module of claim 10 , wherein the substrate support module further includes a thermocouple configured to measure temperature of the platen, the thermocouple located inside a ceramic tube attached to an underside of the platen at a location inside the stem.
15. The substrate support module of claim 10 , wherein the backside gas tube, the platen and the stem are formed of aluminum nitride.
16. The substrate support module of claim 10 , wherein the backside gas tube is centrally located in the interior of the stem.
17. The substrate support module of claim 10 , wherein the platen includes an outer RF electrode embedded therein and inner electrostatic clamping (ESC) electrodes embedded therein, the inner ESC electrodes coplanar with the outer RF electrode, the outer RF electrode electrically connected to a metallized ceramic power feed rod inside the stem, and each of the inner ESC electrodes electrically connected to a pair of metallized ceramic feed rods inside the stem.
18. The substrate support module of claim 10 , wherein the metallized ceramic tube is connected to the electrode by a stress relief connection, the stress relief connection configured to change shape to accommodate differential thermal expansion between the metallized ceramic tube and the electrode.
19. The substrate support module of claim 10 , wherein the metallized ceramic tube has a length greater than a length of the stem and the metallized ceramic tube includes an electrically conductive coating only on an outer surface thereof.
20. The substrate support module of claim 10 , wherein the at least one backside gas tube comprises first, second and third metallized ceramic tubes and the platen includes first, second and third coplanar electrodes wherein the first electrode is an outer ring-shaped electrode having a diagonally extending feed strip electrically connected to the first metalized ceramic tube and the second and third electrodes are inner D-shaped electrodes electrically connected to the second and third metallized ceramic tubes, the first metallized ceramic tube in fluid communication with a first gas passage extending though the diagonally extending feed strip and a first outlet at a center of an upper surface of the platen, the second metallized ceramic tube in fluid communication with a second gas passage extending through the second electrode and a second outlet in the upper surface of the platen at a first distance from the first outlet, and the third metallized ceramic tube in fluid communication with a third gas passage extending through the third electrode and a third outlet in the upper surface of the platen at a second distance from the first outlet, wherein the first and second distances are no greater than about 1 inch.