Plasma Tuning Rods in Microwave Resonator Plasma Sources

• US 20130082030A1
• Filed: 09/30/2011
• Published: 04/04/2013
• Est. Priority Date: 09/30/2011
• Status: Active Grant

• Current Assignee: Tokyo Electron Limited
• Original Assignee: Tokyo Electron Limited
• Inventors: Zhao, Jianping, Chen, Lee, Funk, Merritt, Iwao, Toshihiko, Ventzek, Peter L.G.
• Granted Patent: US 9,111,727 B2
• Time in Patent Office: Days
• US Class Current: 216/69
• CPC Class Codes: H01J 37/32247 Resonators
• CPC Class Codes: H01J 37/32256 Tuning means
• CPC Class Codes: H01J 37/32935 Monitoring and controlling tubes by information coming from the object and/or discharge
• CPC Class Codes: H01L 22/00 Testing or measuring during manufacture or treatment; Reliability measurements, i.e. testing of parts without further processing to modify the parts as such; Structural arrangements therefor

Abstract

The invention provides a plurality of resonator subsystems. The resonator subsystems can comprise one or more resonant cavities configured to couple electromagnetic (EM) energy in a desired EM wave mode to plasma by generating resonant microwave energy in a resonant cavity adjacent the plasma. The resonator subsystem can be coupled to a process chamber using one or more interface subsystems and can comprise one or more resonant cavities, and each resonant cavity can have a plurality of plasma tuning rods coupled thereto. Some of the plasma tuning rods can be configured to couple the EM-energy from one or more of the resonant cavities to the process space within the process chamber.

Claims

1. A microwave processing system for processing a substrate comprising:

a rectangular process chamber comprising a process space having a substrate holder therein;

a first resonator assembly coupled to the rectangular process chamber using a first interface assembly, the first resonator assembly having an electromagnetic (EM) energy tuning space therein, the first interface assembly including a first set of isolation assemblies, wherein a first set of EM-coupling regions are established in the EM-energy tuning space;

a first set of plasma-tuning rods coupled to the first set of isolation assemblies, the first set of plasma-tuning rods having first plasma-tuning portions configured to control plasma uniformity in the process space and first EM-tuning portions configured in the EM-energy tuning space and coupled to at least one of the first set of EM-coupling regions;

a resonator sensor coupled to the EM-energy tuning space, the resonator sensor being configured to obtain resonator data; and

a controller coupled to the first set of isolation assemblies and the resonator sensor, wherein the controller is configured to control the first set of plasma-tuning rods using the first set of isolation assemblies and the resonator data, thereby controlling the first set of EM-coupling regions in the first EM-energy tuning space and the plasma uniformity in the process space.

2. The microwave processing system of claim 1, further comprising:

a coupling network coupled to the first resonator assembly;

a matching network coupled to the coupling network;

a microwave source coupled to the matching network, wherein the microwave source is configured to operate in a frequency range from 500 MHz to 5000 MHz, wherein the controller is coupled to the microwave source, the matching network and the coupling network, the controller being configured to control the microwave source, the matching network and/or the coupling network, thereby controlling the first set of EM-coupling regions in the EM-energy tuning space and the plasma uniformity in the process space.

3. The microwave processing system of claim 1, further comprising:

a second interface assembly coupled to the first resonator assembly;

a plurality of control assemblies coupled to the second interface assembly; and

a plurality of plasma-tuning slabs coupled to the control assemblies configured proximate to at least one EM-coupling region in the EM-energy tuning space, wherein the controller is coupled to the control assemblies and is configured to control EM-tuning distances established between the plasma-tuning slabs and the first EM-tuning portions of the first set of plasma-tuning rods within the first EM-energy tuning space, thereby controlling the first set of EM-coupling regions in the EM-energy tuning space and the plasma uniformity in the process space.

4. The microwave processing system of claim 1, further comprising:

a plurality of flow elements coupled to the rectangular process chamber and configured to provide process gas to the process space;

a plurality of supply elements coupled to the flow elements; and

a gas supply system coupled to the supply elements, wherein the controller is coupled to the gas supply system, the controller being configured to control the gas supply system, thereby controlling the first set of EM-coupling regions in the EM-energy tuning space and the plasma uniformity in the process space.

5. The microwave processing system of claim 4, wherein the process gas comprises two or more of:

a carbon-containing gas, a fluorine-containing gas, a hydrogen-containing gas, an oxygen-containing gas, and an inert gas.

6. The microwave processing system of claim 1, further comprising:

a cavity-tuning slab configured proximate to a first end of the first EM-energy tuning space in the first resonator assembly;

a first cavity-control assembly coupled to the cavity-tuning slab, wherein the cavity-tuning slab is positioned at a cavity-tuning distance from at least one wall of the first resonator assembly, wherein the controller is coupled to the first cavity-control assembly and is configured to control the cavity-tuning distance, thereby controlling the first set of EM-coupling regions in the EM-energy tuning space and the plasma uniformity in the process space.

7. The microwave processing system of claim 1, further comprising:

a lower electrode configured within the substrate holder; and

a Radio Frequency (RF) generator coupled to the lower electrode, wherein the controller is coupled to the RF generator and is configured to control the RF generator, thereby controlling the first set of EM-coupling regions in the EM-energy tuning space and the plasma uniformity in the process space.

8. The microwave processing system of claim 1, wherein the first resonator assembly is coupled to the rectangular process chamber using one or more baffle members.

9. A microwave processing system for processing a substrate comprising:

a rectangular process chamber comprising a process space having a movable substrate holder therein;

a first resonator assembly coupled to the rectangular process chamber using a first interface assembly, the first resonator assembly having a first electromagnetic (EM) energy tuning space therein, the first interface assembly including a first set of isolation assemblies, wherein a first set of EM-coupling regions are established in the EM-energy tuning space;

a plurality of protection assemblies coupled to the first set of isolation assemblies and extending into the process space, the protection assemblies having isolated protection spaces therein;

a first set of plasma-tuning rods coupled to the first set of isolation assemblies, the first set of plasma-tuning rods having first plasma-tuning portions configured in the isolated protection spaces and first EM-tuning portions configured in the first EM-energy tuning space and coupled to at least one of the first set of EM-coupling regions, where the first plasma-tuning portions are configured to control plasma uniformity in the process space;

a resonator sensor coupled to the EM-energy tuning space, the resonator sensor being configured to obtain resonator data; and

a controller coupled to the first set of isolation assemblies and the resonator sensor, wherein the controller is configured to control the first set of plasma-tuning rods using the first set of isolation assemblies and the resonator data, thereby controlling the first set of EM-coupling regions in the first EM-energy tuning space and the plasma uniformity in the process space.

10. The microwave processing system of claim 9, further comprising:

a coupling network coupled to the first resonator assembly;

a matching network coupled to the coupling network;

a microwave source coupled to the matching network, wherein the microwave source is configured to operate in a frequency range from 500 MHz to 5000 MHz, wherein the controller is coupled to the microwave source, the matching network and the coupling network, the controller being configured to control the microwave source, the matching network and/or the coupling network, thereby controlling the first set of EM-coupling regions in the first EM-energy tuning space and the plasma uniformity in the process space.

11. The microwave processing system of claim 9, further comprising:

a second interface assembly coupled to the first resonator assembly;

a plurality of control assemblies coupled to the second interface assembly; and

a plurality of plasma-tuning slabs coupled to the control assemblies configured proximate to at least one EM-coupling region in the first EM-energy tuning space, wherein the controller is coupled to the control assemblies and is configured to control EM-tuning distances established between the plasma-tuning slabs and the first EM-tuning portions of the first set of plasma-tuning rods within the first EM-energy tuning space, thereby controlling the first set of EM-coupling regions in the EM-energy tuning space and the plasma uniformity in the process space.

12. The microwave processing system of claim 9, further comprising:

a plurality of supply elements coupled to the rectangular process chamber and configured to provide process gas to the process space; and

a gas supply system coupled to the supply elements, wherein the controller is coupled to the gas supply system, the controller being configured to control the gas supply system, thereby controlling the first set of EM-coupling regions in the EM-energy tuning space and the plasma uniformity in the process space.

13. The microwave processing system of claim 12, wherein the process gas comprises two or more of:

a carbon-containing gas, a fluorine-containing gas, a hydrogen-containing gas, an oxygen-containing gas, and an inert gas.

14. The microwave processing system of claim 9, further comprising:

a cavity-tuning slab configured proximate to a first end of the first EM-energy tuning space in the first resonator assembly;

a first cavity-control assembly coupled to the cavity-tuning slab, wherein the cavity-tuning slab is positioned at a cavity-tuning distance from at least one wall of the first resonator assembly, wherein the controller is coupled to the first cavity-control assembly and is configured to control the cavity-tuning distance, thereby controlling the first set of EM-coupling regions in the EM-energy tuning space and the plasma uniformity in the process space.

15. The microwave processing system of claim 9, further comprising:

a first resonator subassembly coupled to a first chamber wall at a first offset and having a third EM-energy tuning space therein;

a third isolation assembly coupled to the first chamber wall and configured to isolate the third EM-energy tuning space from the process space;

a third protection assembly coupled to the third isolation assembly, the third protection assembly being configured at a third location within the process space, wherein the third protection assembly has a third isolated protection space therein and has a third insertion length associated therewith;

a third plasma-tuning rod coupled to the third isolation assembly and having a third plasma-tuning portion extending into the third isolated protection space established in the third protection assembly, and having a third EM-tuning portion extending into a third EM-coupling region within the third EM-energy tuning space; and

a first EM source coupled to the first resonator subassembly, wherein the first EM source is configure to operate at frequencies from about 500 MHz to about 5000 MHz, wherein the controller is coupled to the first EM source, the controller being configured to control the first EM source, thereby controlling the third EM-coupling region in the third EM-energy tuning space and the plasma uniformity in the process space.

16. The microwave processing system of claim 9, further comprising:

a third control assembly coupled to a first resonator subassembly; and

a third plasma-tuning slab coupled to the third control assembly and configured proximate to a third EM-coupling region in a third EM-energy tuning space, wherein the controller is coupled to the third control assembly and is configured to control third EM-tuning distances established between the third plasma-tuning slab and a third EM-tuning portion of a third plasma-tuning rod within the third EM-energy tuning space, thereby controlling the third EM-coupling region in the third EM-energy tuning space and the plasma uniformity in the process space.

17. The microwave processing system of claim 15, further comprising:

a second resonator subassembly coupled to a second chamber wall at a second offset and having a fourth EM-energy tuning space therein;

a fourth isolation assembly coupled to the second chamber wall and configured to isolate the fourth EM-energy tuning space from the process space;

a fourth protection assembly coupled to the fourth isolation assembly, the fourth protection assembly being configured at a fourth location within the process space, wherein the fourth protection assembly has a fourth isolated protection space therein and has a fourth insertion length associated therewith;

a fourth plasma-tuning rod coupled to the fourth isolation assembly and having a fourth plasma-tuning portion extending into the fourth isolated protection space established in the fourth protection assembly, and having a fourth EM-tuning portion extending into a fourth EM-coupling region within the fourth EM-energy tuning space; and

a second EM source coupled to the second resonator subassembly, wherein the second EM source is configure to operate at second frequencies from about 500 MHz to about 5000 MHz, wherein the controller is coupled to the second EM source, the controller being configured to control the second EM source, thereby controlling the fourth EM-coupling region in the fourth EM-energy tuning space and the plasma uniformity in the process space.

18. The microwave processing system of claim 17, further comprising:

a fourth control assembly coupled to the second resonator subassembly; and

a fourth plasma-tuning slab coupled to the fourth control assembly and configured proximate to the fourth EM-coupling region in the fourth EM-energy tuning space, wherein the controller is coupled to the fourth control assembly and is configured to control a fourth EM-tuning distance established between the fourth plasma-tuning slab and the fourth EM-tuning portion of the fourth plasma-tuning rod within the fourth EM-energy tuning space, thereby controlling the fourth EM-coupling region in the fourth EM-energy tuning space and the plasma uniformity in the process space.

19. A method of processing a substrate using a microwave processing system comprising:

positioning the substrate on a movable substrate holder within a process space in a rectangular process chamber;

coupling a first resonator assembly to the rectangular process chamber using a first interface assembly, the first resonator assembly having a first electromagnetic (EM) energy tuning space therein, the first interface assembly comprising a first set of isolation assemblies, wherein first EM-coupling regions are established in the EM-energy tuning space;

coupling a first set of plasma-tuning rods to the first set of isolation assemblies, the first set of plasma-tuning rods having first plasma-tuning portions configured in the process space and first EM-tuning portions configured in the EM-energy tuning space and coupled to at least one of a first set of EM-coupling regions;

providing process gas to the process space using a plurality of supply elements coupled to the rectangular process chamber, wherein a gas supply system is coupled to the supply elements;

applying tunable microwave energies to the first set of plasma-tuning rods, thereby creating a uniform microwave plasma in the process space; and

moving the substrate through the uniform microwave plasma, thereby processing the substrate.

20. The method of claim 19, further comprising:

coupling a second interface assembly to the first resonator assembly;

coupling a plurality of control assemblies to the second interface assembly;

coupling a plurality of plasma-tuning slabs to the control assemblies configured proximate to at least one EM-coupling region in the EM-energy tuning space; and

coupling a controller to the control assemblies, wherein the controller is configured to control EM-tuning distances established between the plasma-tuning slabs and the first EM-tuning portions of the first set of plasma-tuning rods within the first EM-energy tuning space, thereby controlling the first set of EM-coupling regions in the EM-energy tuning space and plasma uniformity in the process space.