PLASMA PROCESSING APPARATUS

• US 20110146910A1
• Filed: 06/05/2009
• Published: 06/23/2011
• Est. Priority Date: 06/11/2008
• Status: Abandoned Application

• Current Assignee: Tohoku University National Universities Corporation, Tokyo Electron Limited
• Original Assignee: Tohoku University National Universities Corporation, Tokyo Electron Limited
• Inventors: Ohmi, Tadahiro, Hirayama, Masaki
• Application Number:
  US12/997,122
• Publication Number:
  US 20110146910A1
• Time in Patent Office: Days
• US Class Current: 156/345.43
• CPC Class Codes: H01J 37/32192 Microwave generated discharge H01J37/32357, H01J37/32366, H01J37/32394, H01J37/32403 take precedence
• CPC Class Codes: H01J 37/3222 Antennas
• CPC Class Codes: H01J 37/32238 Windows
• CPC Class Codes: H05H 1/46 using applied electromagnetic fields, e.g. high frequency or microwave energy H05H1/26 takes precedence

Abstract

Uniformity of a process on a substrate is improved. A plasma processing apparatus including a processing container which is formed of metal and receives a substrate to be plasma-processed, an electromagnetic wave source which supplies an electromagnetic wave required to excite plasma in the processing container, and a plurality of dielectrics, through which the electromagnetic wave supplied from the electromagnetic wave source transmits to the inside of the processing container and which have a part that is exposed to the inside of the processing container, on a lower surface of a lid of the processing container, wherein a metal electrode, which is electrically connected to the lid, is formed on a lower surface of each dielectric, a part of each dielectric exposed between the lower surface of the lid and the metal electrode has a substantially polygonal outline when viewed from the inside of the processing container, the plurality of dielectrics are disposed with vertical angles of the polygonal outlines being adjacent to each other, and a surface wave propagating portion, through which the electromagnetic wave is propagated, is formed on the lower surface of the lid exposed inside the processing container and a lower surface of the metal electrode.

Claims

1. A plasma processing apparatus comprising a processing container which is formed of metal and receives a substrate to be plasma-processed, an electromagnetic wave source which supplies an electromagnetic wave required to excite plasma in the processing container, and a plurality of dielectrics, through which the electromagnetic wave supplied from the electromagnetic wave source transmits to the inside of the processing container and which have a part that is exposed to the inside of the processing container, provided on a lower surface of a lid of the processing container,

wherein a metal electrode is provided on a lower surface of each of the dielectrics, and

wherein a surface wave propagating portion, through which the electromagnetic wave is propagated, is formed on each of two different sides of such part of each dielectric that is exposed between the metal electrode and the lower surface of the lid, and the surface wave propagating portion on said two different sides have the substantially similar shapes as each other or the substantially symmetrical shapes to each other.

4. The plasma processing apparatus of claim 1, wherein the dielectrics have substantially tetragonal plate shapes;

5. The plasma processing apparatus of claim 4, wherein the tetragon is a square, a rhomb, a square having round corners, or a rhomb having round corners.

6. The plasma processing apparatus of claim 1, wherein the dielectrics have substantially triangular plate shapes.

7. The plasma processing apparatus of claim 6, wherein the triangle is an equilateral triangle, or an equilateral triangle having round corners.

8. The plasma processing apparatus of claim 1, wherein a shape of the lower surface of the lid, which is surrounded by the plurality of dielectrics and exposed inside the processing container, and a shape of a lower surface of the metal electrode are substantially identical, when viewed from the inside of the processing container.

9. The plasma processing apparatus of claim 1, wherein an outer edge of each dielectric is on an outer side than an outer edge of the metal electrode, when viewed from the inside of the processing container.

10. The plasma processing apparatus of claim 1, wherein an outer edge of each dielectric is on a same line as or on an inner side than an outer edge of the metal electrode, when viewed from the inside of the processing container.

11. The plasma processing apparatus of claim 1, wherein a thickness of each dielectric is equal to or less than 1/29 of a distance between centers of the neighboring dielectrics.

12. The plasma processing apparatus of claim 1, wherein a thickness of each dielectric is equal to or less than 1/40 of a distance between centers of the neighboring dielectrics.

13. The plasma processing apparatus of claim 1, wherein the dielectrics are inserted into a recess portion formed on the lower surface of the lid.

14. The plasma processing apparatus of claim 13, wherein the lower surface of the lid exposed inside the processing container and a lower surface of the metal electrode are disposed on a same plane.

15. The plasma processing apparatus of claim 13, wherein the lower surface of the lid exposed inside the processing container and a lower surface of the metal electrode are covered by a passivation protective film.

16. The plasma processing apparatus of claim 1, wherein an average roughness about the center line in the lower surface of the lid exposed inside the processing container and a lower surface of the metal electrode is 2.4 μ

m or less.

17. The plasma processing apparatus of claim 1, wherein an average roughness about the center line in the lower surface of the lid exposed inside the processing container and a lower surface of the metal electrode is 0.6 μ

m or less.

18. The plasma processing apparatus of claim 1, wherein a metal cover electrically connected to the lid is attached to a region adjacent to each dielectric, in the lower surface of the lid, and

a surface wave propagating portion, through which an electromagnetic wave is propagated, is formed on a lower surface of the metal cover exposed inside the processing container.

19. The plasma processing apparatus of claim 18, wherein a side surface of the dielectric is adjacent to a side surface of the metal cover.

20. The plasma processing apparatus of claim 18, wherein the lower surface of the metal cover exposed inside the processing container and the lower surface of the metal electrode are disposed on a same plane.

21. The plasma processing apparatus of claim 18, wherein a shape of the lower surface of the metal cover and a shape of the lower surface of the metal electrode are substantially same, when viewed from the inside of the processing container.

22. The plasma processing apparatus of claim 18, wherein an average roughness about the center line in the lower surface of the metal cover exposed inside the processing container and the lower surface of the metal electrode is 2.4 μ

m or less.

23. The plasma processing apparatus of claim 18, wherein average roughness about the center line in the lower surface of the metal cover exposed inside the processing container and the lower surface of the metal electrode is 0.6 μ

m or less.

24. The plasma processing apparatus of claim 1, comprising a plurality of connecting members, which penetrate through holes formed on the dielectrics, and fix the metal electrode to the lid.

25. The plasma processing apparatus of claim 24, wherein an elastic member, which electrically connects the lid and the metal electrode, is disposed on at least a part of the holes formed on the dielectrics.

26. The plasma processing apparatus of claim 24, wherein the connecting members are formed of a metal.

27. The plasma processing apparatus of claim 24, wherein lower surfaces of the connecting members exposed inside the processing container are disposed on a same plane as the lower surface of the metal electrode.

28. The plasma processing apparatus of claim 24, wherein each dielectric has a substantially tetragonal plate shape, and the connecting members are disposed on a diagonal of the tetragon.

29. The plasma processing apparatus of claim 28, wherein four connecting members are disposed per one dielectric.

30. The plasma processing apparatus of claim 1, comprising an elastic member, which elastically supports the dielectric and the metal electrode toward the lid.

31. The plasma processing apparatus of claim 1, wherein a continuous groove is formed on the lower surface of the lid, and the surface wave propagating portion and the plurality of dielectrics are disposed inside a region surrounded by the groove.

32. The plasma processing apparatus of claim 31, wherein the surface wave propagating portion is divided by the groove.

33. The plasma processing apparatus of claim 1, wherein a continuous convex portion is formed on an inner side of the processing container, and the surface wave propagating portion and the plurality of dielectrics are disposed in a region surrounded by the convex portion.

34. The plasma processing apparatus of claim 33, wherein the surface wave propagating portion is divided by the convex portion.

35. The plasma processing apparatus of claim 1, comprising one or more metal rods which are on upper portions of the dielectrics, do not penetrate through the dielectrics, have lower ends adjacent to or close to upper surfaces of the dielectrics, and transmit an electromagnetic wave to the dielectrics.

36. The plasma processing apparatus of claim 35, wherein the metal rods are disposed on center portions of the dielectrics.

37. The plasma processing apparatus of claim 35, comprising a sealing member, which divides an atmosphere inside the processing container from an atmosphere outside the processing container, between the dielectrics and the lid.

38. The plasma processing apparatus of claim 1, wherein an area of exposed parts of the dielectrics is equal to or less than ½

of an area of the surface wave propagating portion.

39. The plasma processing apparatus of claim 1, wherein an area of exposed parts of the dielectrics is equal to or less than ⅕

of an area of the surface wave propagating portion.

40. The plasma processing apparatus of claim 1, comprising a gas discharging unit which is on the surface wave propagating portion and discharges a predetermined gas to the processing container.

41. The plasma processing apparatus of claim 1, wherein an area of exposed parts of the dielectrics is equal to or less than ⅕

of an area of an upper surface of the substrate.

42. The plasma processing apparatus of claim 1, wherein a frequency of an electromagnetic wave supplied from the electromagnetic wave source is equal to or less than 2 GHz.

2. A plasma processing apparatus comprising a processing container which is formed of metal and receives a substrate to be plasma-processed, an electromagnetic wave source which supplies an electromagnetic wave required to excite plasma in the processing container, and a plurality of dielectrics, through which the electromagnetic wave supplied from the electromagnetic wave source transmits to the inside of the processing container and which have a part that is exposed to the inside of the processing container, provided on a lower surface of a lid of the processing container,

wherein a metal electrode is provided on a lower surface of each of the dielectrics, and

wherein a surface wave propagating portion, through which the electromagnetic wave is propagated, is formed adjacent to at least a portion of such part of each dielectrics that is exposed between the metal electrode and the lower surface of the lid, and said adjacent surface wave propagating portion has a substantially similar shape as a shape of the dielectric or substantially symmetrical shape to the shape of the dielectric.

3. A plasma processing apparatus comprising a processing container which is formed of metal and receives a substrate to be plasma-processed, an electromagnetic wave source which supplies an electromagnetic wave required to excite plasma in the processing container, and a plurality of dielectrics, through which the electromagnetic wave supplied from the electromagnetic wave source transmits to the inside of the processing container and which have a part that is exposed to the inside of the processing container, provided on a lower surface of a lid of the processing container,

wherein a metal electrode is provided on a lower surface of each of the dielectrics, and

such part of each dielectric that is exposed between the metal electrode and the lower surface of the lid has a substantially polygonal outline when viewed from the inside of the processing container, and

wherein the plurality of dielectrics are disposed with vertical angles of the polygonal outlines being adjacent to each other, and

a surface wave propagating portion, through which the electromagnetic wave is propagated, is formed on the lower surface of the lid exposed in the processing container and a lower surface of the metal electrode.