Plasma processing apparatus

• US 20040221809A1
• Filed: 06/07/2004
• Published: 11/11/2004
• Est. Priority Date: 05/26/1999
• Status: Active Grant

• Current Assignee: Tadahiro Ohmi, Tokyo Electron Limited
• Original Assignee: Tadahiro Ohmi, Tokyo Electron Limited
• Inventors: Ohmi, Tadahiro, Hirayama, Masaki
• Granted Patent: US 7,520,245 B2
• Time in Patent Office: Days
• US Class Current: 118/715
• CPC Class Codes: C23C 16/24 Deposition of silicon only
• CPC Class Codes: C23C 16/345 Silicon nitride
• CPC Class Codes: C23C 16/45565 Shower nozzles
• CPC Class Codes: C23C 16/45578 Elongated nozzles, tubes with holes
• CPC Class Codes: C23C 16/511 using microwave discharges
• CPC Class Codes: H01J 37/32192 Microwave generated discharge H01J37/32357, H01J37/32366, H01J37/32394, H01J37/32403 take precedence
• CPC Class Codes: H01J 37/3244 Gas supply means

Abstract

In a microwave plasma processing apparatus, a metal made lattice-like shower plate 111 is provided between a dielectric material shower plate 103, and a plasma excitation gas mainly an inert gas and a process gas are discharged form different locations. High energy ions can be incident on a surface of the substrate 114 by grounding the lattice-like shower plate. The thickness of each of the dielectric material separation wall 102 and the dielectric material at a microwave introducing part is optimized so as to maximize the plasma excitation efficiency, and, at the same time, the distance between the slot antenna 110 and the dielectric material separation wall 102 and a thickness of the dielectric material shower plate 103 are optimized so as to be capable of supplying a microwave having a large power.

Claims

1-15. -15. (Canceled)

16. A plasma processing apparatus for applying a process to a substrate to be processed, the plasma processing apparatus comprising:

a chamber of which interior can be depressurized;

a gas supply system constructed and arranged to supply a gas to the chamber and an exhaust gas system configured and arranged to exhaust the gas supplied to the chamber and to depressurize the chamber;

a part of a wall constituting the chamber being a flat plate dielectric material plate formed of a material which passes a microwave therethrough substantially without a loss;

a flat plate dielectric material shower plate, which is formed of a material which passes a microwave therethrough substantially without a loss, being provided between the dielectric material plate and plasma excited in the chamber;

a plurality of gas discharge holes being formed in the dielectric material shower plate so that at least a part of the gas supplied by the gas supply system is discharged through the plurality of gas discharge holes through a gap between the dielectric material plate and the dielectric material shower plate;

a flat plate slot antenna being provided on an outer side of the chamber with the dielectric material plate interposed therebetween so as to supply a microwave for exciting plasma through the dielectric material plate;

an electrode being provided on an inner side of the chamber so as to hold the substrate to be processed; and

a substantially flat shower head provided between the dielectric material shower plate and the substrate to be processed so as to discharge a gas, which has a composition different from that of the gas discharged from the dielectric material shower plate, to a side of the substrate to be processed, said shower head having a plurality of openings which cause the plasma, which is generated in a space between the dielectric material shower plate and the shower head, to pass therethrough and flow to the side of the substrate,

wherein said dielectric material shower plate and said shower head are arranged substantially parallel to each other, and a distance therebetween is substantially equal to a multiple of a quarter of a wavelength of said microwave in a vacuum.

17. The plasma processing apparatus as claimed in claim 16, wherein a plurality of gas discharge holes are provided to the shower head on a side facing the substrate to be processed.

18. The plasma processing apparatus as claimed in claim 16, wherein said shower head is formed of a metal pipe having a plurality of gas discharge holes on a side facing the substrate to be processed, and the metal pipe is grounded.

19. The plasma processing apparatus as claimed in claim 18, wherein said metal pipe is formed of a stainless steel containing aluminum, and a surface thereof is covered by a passivation film mainly formed of aluminum oxide.

20. The plasma processing apparatus as claimed in claim 16, wherein said dielectric material plate and said dielectric material shower plate are arranged substantially parallel to each other, and a distance between a surface of said dielectric material plate facing said slot antenna and a surface of the dielectric material shower plate facing said substrate to be processed is substantially equal to an odd multiple of a quarter of a wavelength of said microwave in a corresponding part.

21. The plasma processing apparatus as claimed in claim 16 wherein said slot antenna and said dielectric material plate are arranged substantially parallel to each other, and a distance therebetween is substantially equal to an odd multiple of a quarter of a wavelength of said microwave in a corresponding part.

22. The plasma processing apparatus as claimed in claim 16, wherein a thickness of said dielectric material shower palate is an integral multiple of a half of a wavelength of said microwave in a corresponding part.

23. The plasma processing apparatus as claimed in claim 22, wherein said slot antenna and said dielectric material plate are arranged substantially parallel to each other, and a distance therebetween is substantially equal to an odd multiple of a quarter of a wavelength of said microwave in a corresponding part.

24. A plasma processing method of applying a process to a substrate to be processed, comprising:

supplying a first gas through an upper shower head;

generating plasma using the first gas;

supplying the plasma to the substrate to be processed by flowing the plasma to pass through an opening formed in a lower shower head, which is located under the upper shower head in parallel with a predetermined distance therebetween and configured and arranged to supply a second gas to the substrate to be processed; and

processing the substrate to be processed using the plasma passed through the opening of the lower shower head and the second gas supplied by the lower shower head.

25. The plasma processing method as claimed in claim 24, wherein the step of generating the plasma includes applying a microwave to the first gas through the upper shower head.

26. The plasma processing method as claimed in claim 25, wherein the predetermined distance between the upper shower head and the lower shower head is equal to a multiple of a quarter of a wavelength of said microwave in a vacuum.