Systems and methods for internal surface conditioning assessment in plasma processing equipment

• US 9,966,240 B2
• Filed: 10/14/2014
• Issued: 05/08/2018
• Est. Priority Date: 10/14/2014
• Status: Active Grant

• Current Assignee: Applied Materials Incorporated
• Original Assignee: Applied Materials Incorporated
• Inventors: Park, Soonam, Zhu, Yufei, Suarez, Edwin C., Ingle, Nitin K., Lubomirsky, Dmitry, Huang, Jiayin
• Primary Examiner(s): Yu, Yuechuan
• Application Number:
  US14/514,222
• Publication Number:
  US 20160104606A1
• Time in Patent Office: 1,302 Days
• CPC Class Codes: C23C 16/4405 Cleaning of reactor or parts inside the reactor by using reactive gases
• CPC Class Codes: C23C 16/452 by activating reactive gas streams before their introduction into the reaction chamber, e.g. by ionisation or addition of reactive species
• CPC Class Codes: C23C 16/45565 Shower nozzles
• CPC Class Codes: C23C 16/50 using electric discharges generation and control of plasma in discharge tubes for surface treatment H01J37/32, H01J37/34
• CPC Class Codes: C23C 16/52 Controlling or regulating the coating process C23C16/45557, C23C16/279 take precedence
• CPC Class Codes: G01J 3/0218 using optical fibers
• CPC Class Codes: G01J 3/443 Emission spectrometry
• CPC Class Codes: H01J 37/32082 Radio frequency generated discharge H01J37/32357, H01J37/32366, H01J37/32394 and H01J37/32403 take precedence
• CPC Class Codes: H01J 37/32532 Electrodes
• CPC Class Codes: H01J 37/3255 Material
• CPC Class Codes: H01J 37/32935 Monitoring and controlling tubes by information coming from the object and/or discharge
• CPC Class Codes: H01J 37/32963 End-point detection
• CPC Class Codes: H01J 37/32972 Spectral analysis
• CPC Class Codes: H01J 37/3299 Feedback systems
• CPC Class Codes: H01L 21/3065 Plasma etching; Reactive-ion etching
• CPC Class Codes: H01L 21/31116 by dry-etching
• CPC Class Codes: H01L 21/31138 by dry-etching
• CPC Class Codes: H01L 21/32136 using plasmas
• CPC Class Codes: H01L 21/67069 for drying etching
• CPC Class Codes: H01L 22/26 Acting in response to an ongoing measurement without interruption of processing, e.g. endpoint detection, in-situ thickness measurement endpoint detection arrangements in CMP apparatus B24B37/013, in discharge apparatus H01J37/32

Abstract

In an embodiment, a plasma source includes a first electrode, configured for transfer of one or more plasma source gases through first perforations therein; an insulator, disposed in contact with the first electrode about a periphery of the first electrode; and a second electrode, disposed with a periphery of the second electrode against the insulator such that the first and second electrodes and the insulator define a plasma generation cavity. The second electrode is configured for movement of plasma products from the plasma generation cavity therethrough toward a process chamber. A power supply provides electrical power across the first and second electrodes to ignite a plasma with the one or more plasma source gases in the plasma generation cavity to produce the plasma products. One of the first electrode, the second electrode and the insulator includes a port that provides an optical signal from the plasma.

Claims

1. A plasma source, comprising:

a first perforated electrode comprising a first planar surface that is configured for transfer of one or more plasma source gases through first perforations therein;

a second perforated electrode comprising a second planar surface that is configured for movement of plasma products therethrough toward a process chamber, the second electrode being held at electrical ground;

an insulator having upper and lower surfaces that are disposed in contact with the first and second planar surfaces about a periphery of the first perforated electrode and a periphery of the second perforated electrode, such that the first and second perforated electrodes and the insulator define a plasma generation cavity; and

a power supply that provides electrical power across the first and second perforated electrodes to ignite a plasma with the one or more plasma source gases in the plasma generation cavity to produce the plasma products;

wherein the insulator includes a port that provides an optical signal from the plasma, the port comprising;

a radial aperture formed within the insulator;

an optical window that is sealable to the insulator across an outer opening of the radial aperture, and

a fixture that positions a fiber optic adjacent the optical window such that optical emissions from the plasma propagate into the fiber optic to form the optical signal, the fiber being oriented such that the optical signal is limited to optical emissions originating within the plasma generation cavity.

2. The plasma source of claim 1, wherein the optical signal is not influenced by interactions of the plasma products after they move through the second perforated electrode toward the process chamber.

3. The plasma source of claim 1, wherein the insulator is a ceramic ring.

4. The plasma source of claim 1, wherein the optical window comprises sapphire or quartz.

5. The plasma source of claim 1, further comprising an optical emission spectrometer that receives the optical signal and generates emission peak data from the optical signal.

6. The plasma source of claim 5, further comprising a computer configured for generating records of the emission peak data.

7. The plasma source of claim 6, the emission peak data including hydrogen emission peak data, the computer being configured to calculate a stability metric of the hydrogen emission peak data over sequential process sequences of the plasma source.

8. The plasma source of claim 1, wherein at least one of the first and second perforated electrodes comprises yttria.

9. The plasma source of claim 1, the one or more source gases comprising a fluorine source.

10. The plasma source of claim 9, the fluorine source comprising NF₃.

11. The plasma source of claim 1, wherein the first planar surface of the first perforated electrode extends along a single plane from a perforated center region of the first perforated electrode, to the periphery where the first planar surface is disposed in contact with the upper surface of the insulator.

12. The plasma source of claim 1, wherein the second planar surface of the second perforated electrode extends along a single plane from a perforated center region of the second perforated electrode, to the periphery where the second planar surface is disposed in contact with the lower surface of the insulator.