Source and method for generating high-density plasma with inductive power coupling

• US 5,397,962 A
• Filed: 06/29/1992
• Issued: 03/14/1995
• Est. Priority Date: 06/29/1992
• Status: Expired due to Term

• Current Assignee: Texas Instruments, Inc.
• Original Assignee: Texas Instruments, Inc.
• Inventors: Moslehi, Mehrdad M.
• Primary Examiner(s): Pascal, Robert J.
• Assistant Examiner(s): Shingleton, Michael B.
• Application Number:
  US07/905,982
• Time in Patent Office: 988 Days
• Field of Search: 315/111.21, 315/111.51, 315/111.81, 219/121.52, 204/192.1, 204/298.04
• US Class Current: 315/111.51
• CPC Class Codes: H05H 1/46 using applied electromagnetic fields, e.g. high frequency or microwave energy H05H1/26 takes precedence

Abstract

A source and method for generating high density plasma with inductive radio-frequency power coupling is provided in which coil antenna sections (34) within a plasma source (12) are used to generate a high-density uniform plasma. This plasma is then guided into transferred in a transfer chamber (14) and then to a processing chamber (16). Within the processing chamber (16), the plasma reacts with a semiconductor wafer (18) or another workpiece for plasma-enhanced deposition or etch processing.

Claims

1. A high density plasma source, comprising:

a plasma formation chamber having inlets for injecting plasma gases;

a magnet disposed around said plasma formation chamber and operable to generate an axial magnetic field within said plasma formation chamber; and

a plurality of coil antenna sections disposed within said plasma formation chamber operable to generate a second magnetic field, such that a plasma is generated, said second magnetic field inductively coupled to said plasma and wherein said plurality of coil antenna sections are interconected such that said second magnetic field rotates relative to said axial magnetic field and said plasma formation chamber.

2. The plasma source of claim 1, wherein said magnet comprises a permanent magnet.

3. The plasma source of claim 1, wherein said magnet comprises an electromagnet.

4. The plasma source of claim 1, wherein said plasma formation chamber is substantially cylindrical and said magnet is disposed substantially concentrically around said plasma formation chamber.

5. The plasma source of claim 1, wherein said plasma formation chamber is substantially cylindrical, and wherein said plurality of coil antenna sections are spaced apart and disposed axially within said plasma formation chamber.

6. The plasma source of claim 5, wherein said plurality of coil antenna sections are substantially equidistant from an axis of said plasma formation chamber.

7. The plasma source of claim 1, wherein said plurality of coil antenna sections are interconnected such that said second magnetic field is transverse to said axial magnetic field.

8. The plasma source of claim 1, wherein said plurality of coil antenna sections are coupled to a plurality of radio-frequency power sources having a frequency such that said second magnetic field rotates at the rate of said frequency.

9. The plasma source of claim 1, wherein said plurality of coil antenna sections are coupled to a plurality of out of phase radio-frequency power sources.

10. The plasma source of claim 1, wherein said plasma formation chamber further comprises an end plate, said end plate having a plurality of electrical feedthroughs for said plurality of coil antenna sections.

11. The plasma source of claim 1, wherein said plasma formation chamber comprises channels, said channels operable to flow a coolant to dissipate heat.

12. The plasma source of claim 1, wherein said coil antenna sections are hollow, said hollow coil antenna sections operable to flow a coolant to dissipate heat.

13. The plasma source of claim 1, wherein each of said coil antenna sections are disposed within one of a plurality of non-reactive tubes.

14. The plasma source of claim 1, wherein said coil antenna sections terminate in a connector ring disposed within said plasma formation chamber.

15. A method of generating a high-density plasma, comprising the steps of:

injecting plasma gases into a plasma formation chamber;

generating an axial magnetic field, the magnetic field having components within the plasma formation chamber; and

generating a second magnetic field inductively coupled to the high-density plasma, the second magnetic field generated within the plasma formation chamber and wherein said second magnetic field rotates with respect to said axial magnetic field.

16. A method of generating a high-density plasma, comprising the steps of:

injecting plasma gases into a plasma formation chamber;

generating an axial magnetic field, the magnetic field having components within the plasma formation chamber; and

generating a second magnetic field inductively coupled to the high-density plasma, the second magnetic field generated within the plasma formation chamber wherein said second magnetic field rotates with respect to said axial magnetic field.

17. The method of claim 16, wherein the second magnetic field is transverse to the axial magnetic field.

18. The method of claim 16, and further comprising the step of cooling the plasma formation chamber with a coolant.