Plasma processing apparatus and plasma processing method

• US 8,006,640 B2
• Filed: 03/26/2007
• Issued: 08/30/2011
• Est. Priority Date: 03/27/2006
• Status: Active Grant

• Current Assignee: Tokyo Electron Limited
• Original Assignee: Tokyo Electron Limited
• Inventors: Sasaki, Masaru
• Primary Examiner(s): Maldonado; Julio J
• Application Number:
  US11/691,154
• Publication Number:
  US 20070221294A1
• Time in Patent Office: 1,618 Days
• Field of Search: 118/723.MW, 118/723.AN, 118/723.R, 118/723.ME, 118/723.MR, 438/772, 438/777, 156/345.41, 156/345.36, 343/767, 343/770, 343/771
• US Class Current: 118/723.0AN
• 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 37/32458 Vessel
• CPC Class Codes: H01L 21/0217 the material being a silicon nitride not containing oxygen, e.g. SixNy or SixByNz H01L21/02126 and H01L21/0214 take precedence
• CPC Class Codes: H01L 21/0223 formation by oxidation, e.g. oxidation of the substrate
• CPC Class Codes: H01L 21/02238 silicon in uncombined form, i.e. pure silicon
• CPC Class Codes: H01L 21/02247 formation by nitridation, e.g. nitridation of the substrate
• CPC Class Codes: H01L 21/02252 formation by plasma treatment, e.g. plasma oxidation of the substrate after treatment of an insulating film by plasma H01L21/3105 and subgroups
• CPC Class Codes: H01L 21/31662 of silicon in uncombined form
• CPC Class Codes: H01L 21/3185 of siliconnitrides

Abstract

A plasma processing apparatus includes: a process container configured to accommodate a target object and hold a vacuum therein for performing a plasma process; a worktable configured to place the target object thereon inside the process container; a planar antenna including a plurality of slots and configured to supply microwaves into the process container; a gas feed mechanism configured to supply a process gas into the process container; and a top plate disposed opposite the worktable, the top plate being set at a position separated from the target object placed on the worktable by a distance of 20 mm or more and 100 mm or less.

Claims

1. A plasma processing apparatus comprising:

a process container configured to hold a vacuum therein and perform a plasma process on a target object accommodated therein, the process container including a container casing that is equipped with an upper plate disposed on an upper side thereof and defining a top opening, and a dielectric transmission plate supported by the upper plate and airtightly closing the top opening;

a worktable configured to place the target object thereon inside the process container;

a planar antenna disposed above the transmission plate and including a plurality of slots to supply microwaves from the slots through the transmission plate into the process container;

a gas feed member configured to supply a process gas, to be turned into plasma by the microwaves, into the process container;

an exhaust line configured to exhaust gas from inside the process container;

a dielectric wave-retardation body disposed above the planar antenna and configured to shorten a wavelength of the microwaves; and

a metal cover covering the planar antenna and the wave-retardation body,

wherein the planar antenna is fixed at a periphery of the planar antenna to the metal cover by fixing members, which are fitted in a recess formed on the transmission plate at a periphery of the transmission plate, and

the transmission plate is set at a position where the transmission plate is separated from the target object placed on the worktable by a distance of from 20 mm to 100 mm.

2. The plasma processing apparatus according to claim 1, wherein the recess is formed as an annular recess on the transmission plate at a periphery of the transmission plate.

3. The plasma processing apparatus according to claim 1, wherein the transmission plate includes a dished recess formed on a lower surface facing the target object, and the distance is defined by a distance between the target object and a thin portion of the transmission plate corresponding to the dished recess.

4. The plasma processing apparatus according to claim 3, wherein the thin portion of the transmission plate has a thickness of λ

g/4 or more, where λ

g is the wavelength of the microwaves.

5. A plasma processing apparatus comprising:

a process container configured to hold a vacuum therein and perform a plasma process on a target object accommodated therein, the process container including a container casing that is equipped with an upper plate disposed on an upper side thereof and defining a top opening, and a dielectric transmission plate supported by the upper plate and airtightly closing the top opening through a first seal member;

a worktable configured to place the target object thereon inside the process container;

a planar antenna disposed above the transmission plate and including a plurality of slots to supply microwaves from the slots through the transmission plate into the process container;

a gas feed member configured to supply a process gas, to be turned into plasma by the microwaves, into the process container;

an exhaust line configured to exhaust gas from inside the process container;

a dielectric wave-retardation body disposed above the planar antenna and configured to shorten a wavelength of the microwaves;

a metal cover covering the planar antenna and the wave-retardation body;

a first presser member that presses the transmission plate to the upper plate via a first fixing member, the first presser member being set in contact with the transmission plate at a periphery of the transmission plate with a second seal member interposed between the first presser member and the periphery of the transmission plate, and the first presser member being in contact with a top portion of the upper plate with a third seal member of a metal seal ring interposed between the first presser member and the top portion of the upper plate; and

a second presser member that presses the metal cover to the first presser member via a second fixing member, the second presser member being set in contact with the metal cover at a periphery of the metal cover with a fourth seal member of a metal seal ring interposed between the second presser member and the periphery of the metal cover, and the second presser member being in contact with the first presser member with a fifth seal member of a metal seal ring interposed between the second presser member and the first presser member,

wherein the transmission plate is set at a position where the transmission plate is separated from the target object placed on the worktable by a distance of from 20 mm to 100 mm.

6. The plasma processing apparatus according to claim 5, wherein the planar antenna is fixed at a periphery of the planar antenna to the metal cover by fixing members, which are fitted in a recess formed on the transmission plate at a periphery of the transmission plate.

7. The plasma processing apparatus according to claim 6, wherein the recess is formed as an annular recess on the transmission plate at a periphery of the transmission plate.

8. The plasma processing apparatus according to claim 5, wherein the transmission plate includes a dished recess formed on a lower surface facing the target object, and the distance is defined by a distance between the target object and a thin portion of the transmission plate corresponding to the dished recess.

9. The plasma processing apparatus according to claim 8, wherein the thin portion of the transmission plate has a thickness of λ

g/4 or more, where λ

g is the wavelength of the microwaves.