Methods and apparatus for dynamical control of radial uniformity with two-story microwave cavities

Patent metadata

Field	Value
Publication number	US-11348783-B2
Application number	US-201916562002-A
Country	US
Kind code	B2
Filing date	Sep 5, 2019
Priority date	Sep 5, 2019
Publication date	May 31, 2022
Grant date	May 31, 2022

Abstract

Methods and apparatus provide plasma generation for semiconductor process chambers. In some embodiments, the plasma is generated by a system that may comprise a process chamber having at least two upper microwave cavities separated from a lower microwave cavity by a metallic plate with a plurality of radiation slots, at least one microwave input port connected to a first one of the at least two upper microwave cavities, at least two microwave input ports connected to a second one of the at least two upper microwave cavities, and the lower microwave cavity receives radiation through the plurality of radiation slots in the metallic plate from both of the at least two upper microwave cavities, the lower microwave cavity is configured to form an electric field that provides uniform plasma distribution in a process volume of the process chamber.

First claim

The invention claimed is:

1. A system for generating plasma for a semiconductor process, comprising:
a process chamber having at least two upper microwave cavities separated from a lower microwave cavity by a metallic plate with a plurality of radiation slots;
at least one microwave input port connected to a first one of the at least two upper microwave cavities, wherein the first one of the at least two upper microwave cavities is a three dimensional rectangular cavity;
at least two microwave input ports connected to a second one of the at least two upper microwave cavities; and
the lower microwave cavity receives radiation through the plurality of radiation slots in the metallic plate from both of the at least two upper microwave cavities, the lower microwave cavity is configured to form an electric field that provides uniform plasma distribution in a process volume of the process chamber.

2. The system of claim 1 , wherein the first one of the at least two upper microwave cavities is a square cavity.

3. The system of claim 1 , wherein the first one of the at least two upper microwave cavities is an air cavity.

4. The system of claim 1 , further comprising:
a tuner on the first one of the at least two upper microwave cavities configured to adjust microwave excitation in the first one of the at least two upper microwave cavities and to act as a bandpass filter for frequencies of center-high modes.

5. The system of claim 1 , wherein the second one of the at least two upper microwave cavities is a toroidal cavity.

6. The system of claim 1 , wherein the second one of the at least two upper microwave cavities is an air cavity.

7. The system of claim 1 , further comprising:
a tuner on the second one of the at least two upper microwave cavities configured to adjust microwave excitation in the second one of the at least two upper microwave cavities and to act as a bandpass filter for frequencies of edge-high modes.

8. The system of claim 1 , wherein the first one of the at least two upper microwave cavities supports a center-high mode of microwave excitation and the second one of the at least two upper microwave cavities supports an edge high mode of microwave excitation.

9. The system of claim 8 , wherein the at least two upper microwave cavities are configured to form an electric field in the lower microwave cavity that produces a uniform plasma by adjusting a power ratio of center-high mode to edge-high mode in the at least two upper microwave cavities.

10. The system of claim 8 , wherein the at least two upper microwave cavities are configured to form an electric field in the lower microwave cavity that produces a uniform plasma by adjusting a power ratio of center-high mode to edge-high mode in the at least two upper microwave cavities.

11. A system for generating plasma for a semiconductor process, comprising:
a process chamber having at least two upper microwave cavities separated from a lower microwave cavity by a metallic plate with a plurality of radiation slots;
at least one microwave input port connected to a first one of the at least two upper microwave cavities, wherein the first one of the at least two upper microwave cavities is a coaxial air cavity;
at least two microwave input ports connected to a second one of the at least two upper microwave cavities; and
the lower microwave cavity receives radiation through the plurality of radiation slots in the metallic plate from both of the at least two upper microwave cavities, the lower microwave cavity is configured to form an electric field that provides uniform plasma distribution in a process volume of the process chamber.

12. The system of claim 11 , wherein the coaxial air cavity excites a TE/M 0XX mode, where X is an integer.

13. The system of claim 11 , wherein the coaxial air cavity has two different circular dimensions.

14. A system for generating plasma for a semiconductor process, comprising:
a first upper microwave cavity that excites center-high modes, wherein the first upper cavity is a three dimensional rectangular cavity;
a second upper microwave cavity that excites edge high modes, the second upper microwave cavity surrounding the first upper microwave cavity;
a metallic plate beneath the first upper microwave cavity and the second upper microwave cavity, the metallic plate has a plurality of radiation slots configured to radiate center-high modes from the first upper microwave cavity and edge-high modes from the second upper microwave cavity; and
a lower microwave cavity that receives radiated center-high modes from the first upper microwave cavity and edge-high modes from the second upper microwave cavity, the lower microwave cavity configured to provide an electric field for uniform plasma distribution in a process chamber.

15. The system of claim 14 , wherein the first upper microwave cavity and the second upper microwave cavity are air cavities and the lower microwave cavity is a quartz cavity.

16. The system of claim 15 , wherein the quartz cavity has a plurality of holes therethrough.

17. The system of claim 15 , wherein the second upper microwave cavity is a toroidal cavity surrounding the first upper microwave cavity.

18. The system of claim 15 , further comprising:
a first tuner on the first upper microwave cavity configured to adjust microwave excitation in the first upper microwave cavity and to act as a bandpass filter for frequencies of center-high modes; and
a second tuner on the second upper microwave cavity configured to adjust microwave excitation in the second upper microwave cavity and to act as a bandpass filter for frequencies of edge-high modes.

19. A system for generating plasma for a semiconductor process, comprising:
a first upper microwave cavity that excites center-high modes, the first upper microwave cavity being a three dimensional rectangular air cavity;
a second upper microwave cavity that excites edge high modes, the second upper microwave cavity being a toroidal air cavity that surrounds the first upper microwave cavity;
a metallic plate beneath the first upper microwave cavity and the second upper microwave cavity, the metallic plate has a plurality of radiation slots configured to radiate center-high modes from the first upper microwave cavity and edge-high modes from the second upper microwave cavity; and
a lower microwave cavity that receives radiated center-high modes from the first upper microwave cavity and edge-high modes from the second upper microwave cavity, the lower microwave cavity being a cylindrical quartz cavity with a plurality of holes therethrough that is configured to provide an electric field for uniform plasma distribution in a process chamber.

20. The system of claim 19 , further comprising:
a first tuner on the first upper microwave cavity configured to adjust microwave excitation in the first upper microwave cavity and to act as a bandpass filter for frequencies of center-high modes; and
a second tuner on the second upper microwave cavity configured to adjust microwave excitation in the second upper microwave cavity and to act as a bandpass filter for frequencies of edge-high modes,
wherein the first upper microwave cavity and the second upper microwave cavity are configured to generate an electric field in the lower microwave cavity that produces a uniform plasma by adjusting a power ratio of center-high mode to edge-high mode in the first upper microwave cavity and the second upper microwave cavity, respectively.

Assignees

• Applied Materials Inc

Inventors

• Kobayashi Satoru
• Sugai Hideo
• Ivanov Denis
• Scudder Lance
• Lubomirsky Dmitry

Classifications

• H10P14/6319 Primary

  Formation by plasma treatments, e.g. plasma oxidation of the substrate · CPC title

• H05B6/806

  for laboratory use · CPC title

• H05B6/6402

  Aspects relating to the microwave cavity · CPC title

• H01J37/32311

  Circuits specially adapted for controlling the microwave discharge · CPC title

• H01J37/32284

  Means for controlling or selecting resonance mode · CPC title