JP3898649B2 - Plasma processing equipment - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a plasma processing apparatus, and more particularly to a plasma processing apparatus capable of generating plasma uniformly and stably.
[0002]
[Prior art]
In a plasma processing apparatus for processing a sample by generating plasma in a vacuum processing chamber, when the inner wall or the like of the vacuum processing chamber is directly exposed to plasma, parts of the processing chamber wall or the processing chamber are consumed. In addition, the sample placed in the processing chamber is contaminated with metal due to the wear of the components. Conventionally, with respect to this metal contamination, an inner cylinder made of a dielectric is provided so as to surround the plasma in the processing chamber to protect the processing chamber wall from the plasma.
[0003]
At this time, if the dielectric inner cylinder is installed eccentrically with respect to the vacuum processing chamber, it becomes difficult to generate plasma uniformly or axially symmetrically.
[0004]
In Patent Document 1, when a dielectric inner cylinder is installed in a processing chamber, a conductive cylinder connected to the ground potential is provided in the processing chamber, and the dielectric inner cylinder and the conductive cylinder are provided. It is shown that the plasma is generated uniformly or axially symmetrical by setting the length of the overlapping portion to 10 mm or more.
[0005]
[Patent Document 1]
Japanese Patent Laid-Open No. 2000-208496
[Problems to be solved by the invention]
As described above, by providing a conductive cylinder fixed to the ground potential and setting the length of the overlapping portion of the dielectric inner cylinder and the conductive cylinder to 10 mm or more, the dielectric Even when a body-made inner cylinder is installed eccentrically with respect to the vacuum processing chamber, it is possible to generate plasma uniformly or symmetrically. However, if the dielectric inner cylinder is installed eccentrically with respect to the vacuum processing chamber, the gap between the dielectric inner cylinder and the conductor vacuum processing chamber wall cannot be maintained uniformly. When the gap cannot be maintained uniformly (for example, when the gap dimension is a predetermined value or less), abnormal discharge occurs in the gap and adversely affects the plasma processing.
[0007]
The present invention has been made in view of these problems, and provides a plasma processing apparatus capable of stably generating plasma uniformly or axially symmetric and processing a sample surface uniformly and stably.
[0008]
[Means for Solving the Problems]
The present invention employs the following means in order to solve the above problems.
[0009]
A vacuum processing container made of a conductive material having a substantially cylindrical shape, a sample stage placed in the vacuum processing container and placing a sample on the upper surface thereof, and a gap between the inner wall surface of the vacuum container and a covering thereof. An inner cylinder member made of a dielectric material, and a grounding member mounted and disposed in the vacuum vessel, on which the inner cylinder member is placed, and using plasma generated inside the inner cylinder member A plasma processing apparatus for processing the sample,
The ground member protrudes from the inner wall surface of the vacuum processing container to the inside of the vacuum processing container and is bent upward from the front portion of the protrusion and the protrusion on which the inner cylinder member is placed, and contacts the plasma. A bent portion,
A plurality of protrusions protruding from the inner wall of the vacuum container located below the upper end of the bending part and above the protrusion between the bent part and the inner wall of the vacuum container; It arrange | positions between the said bending part and the said projection part.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a diagram illustrating a plasma processing apparatus according to an embodiment of the present invention. In the figure, reference numeral 101 denotes a vacuum processing container made of, for example, a cylindrical conductor. Reference numeral 102 denotes a magnetic coil, which generates a magnetic field (for example, 16 mT) having a magnitude that satisfies the condition for establishing ECR (Electron Cyclotron Resonance) in the vacuum processing vessel 101. Reference numeral 103 denotes a high-frequency power source that supplies, for example, a high-frequency UHF wave (450 MHz) to the antenna 105 via the coaxial waveguide 104. The antenna 105 radiates the high frequency into the vacuum processing container through the quartz plate 106 which is a dielectric member. As a result, electron cyclotron resonance (ECR) is generated in the vacuum chamber.
[0011]
A process gas is introduced into the vacuum processing vessel 101 at a predetermined pressure in advance, and is converted into plasma by the electron cyclotron resonance to generate plasma 107. Ions or radicals generated by the plasma 107 irradiate a sample 109 such as a wafer placed on the sample stage 108 to perform an etching process.
[0012]
Reference numeral 110 denotes an inner cylinder member made of a dielectric material such as quartz disposed on the inner surface of the side wall of the vacuum processing container 101 so that the inner wall surface of the processing container 101 is not directly exposed to plasma. Reference numeral 111 denotes a ground member, which includes a protruding portion 111a protruding inward from the inner wall surface of the vacuum processing vessel and a bent portion 111b bent upward from the tip of the protruding portion, and the inner cylinder member 110 is mounted on the protruding portion 111a. Put. The bent portion 111b of the ground member and the dielectric cylinder member 110 are provided with a portion (overlapping portion) 112 that overlaps each other. The bent portion 111b of the ground member is in contact with the plasma 107 generated in the vacuum processing container 101, and fixes the plasma potential of the contact portion to the ground potential. Thereby, the uniformity or axial symmetry of plasma can be further improved. The ground member 111 can be formed continuously along the inner periphery of the cylindrical vacuum processing vessel 101, for example. A plurality of locations (for example, 3 locations) can be provided at substantially equal intervals along the inner periphery.
[0013]
FIG. 2 is a diagram for explaining details of the vicinity of the ground member provided in the vacuum processing container. In the figure, 201 is a portion of the inner surface of the vacuum processing container 101 facing the bent portion 111b, that is, a protrusion formed below the upper end of the bent portion 111b and above the protruding portion 111a. It functions as an anti-bias member that stops the deviation. The protrusion 201 can be formed continuously along the inner periphery of the cylindrical vacuum processing vessel 101, for example. A plurality of locations (for example, 3 locations) can be provided at substantially equal intervals along the inner periphery. Further, the protruding portion 201 can be formed above the overlapping portion 111 b on the inner surface of the vacuum processing container 101.
[0014]
Thus, by providing the protrusion 201, the dielectric inner cylinder 110 can be installed concentrically with the vacuum processing vessel 101. Further, the gap between the inner wall surface of the vacuum processing container 101 and the inner cylinder member 110 can be kept uniform. Thereby, plasma can be generated uniformly or axisymmetrically. Further, the gap between the inner cylinder and the vacuum processing chamber wall can be kept uniform. Thereby, abnormal discharge generated in the gap can be suppressed, and the sample (wafer) can be processed stably.
[0015]
FIG. 3 is a view for explaining processing when the inner cylinder member is inserted and arranged in the vacuum processing container. In the figure, reference numeral 301 denotes a jig used when the inner cylinder member 110 is transported while being inserted and arranged in the vacuum vessel 101. The jig 301 includes a gap holding portion 302 for holding a gap between the inner surface of the vacuum processing container 101 and the outer surface of the inner cylinder member 110.
[0016]
First, after the cylindrical member 110 is inserted and arranged in the vacuum vessel 101, a plurality of (for example, three) jigs 301 are inserted into the gap between the inner surface of the vacuum processing vessel and the outer surface of the inner cylinder member at approximately equal intervals. The member 110 is temporarily fixed. At this time, each jig 301 uses a jig whose dimension (A) of the gap holding portion 302 is substantially the same.
[0017]
After transportation, all the jigs 301 are removed, and then the vacuum processing container is assembled. Thereby, it can convey in the state with which the clearance gap between the vacuum processing container 101 and the inner cylinder member 110 was hold | maintained to the predetermined value.
[0018]
【The invention's effect】
As described above, according to the present invention, it is possible to provide a plasma processing apparatus capable of generating plasma uniformly or axially symmetrically and processing a sample surface uniformly and stably.
[Brief description of the drawings]
FIG. 1 is a diagram illustrating a plasma processing apparatus according to an embodiment of the present invention.
FIG. 2 is a diagram illustrating details of the vicinity of a ground member provided in a vacuum processing chamber.
FIG. 3 is a diagram illustrating a process when an inner cylinder member is inserted and arranged in a vacuum processing container and conveyed.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 101 Vacuum processing container 102 Magnetic coil 103 High frequency power supply 104 Coaxial waveguide 105 Antenna 106 Quartz plate 107 Plasma 108 Sample stand 109 Sample 110 Inner cylinder member 111 Ground member 112 Overlapping part 201 Projection part 301 Jig

Claims (3)

A vacuum processing container made of a conductive material having a substantially cylindrical shape, a sample stage placed in the vacuum processing container and placing a sample on the upper surface thereof, and a gap between the inner wall surface of the vacuum container and a covering thereof. An inner cylinder member made of a dielectric material, and a grounding member mounted and disposed in the vacuum vessel, on which the inner cylinder member is placed, and using plasma generated inside the inner cylinder member A plasma processing apparatus for processing the sample,
The ground member protrudes from the inner wall surface of the vacuum processing container to the inside of the vacuum processing container and is bent upward from the front portion of the protrusion and the protrusion on which the inner cylinder member is placed, and contacts the plasma. A bent portion,
A plurality of protrusions protruding from the inner wall of the vacuum container located below the upper end of the bending part and above the protrusion between the bent part and the inner wall of the vacuum container; The plasma processing apparatus arrange | positioned between the said bending part and the said projection part. A vacuum processing container made of a conductive material having a substantially cylindrical shape, a sample stage placed in the vacuum processing container and placing a sample on the upper surface thereof, and a gap between the inner wall surface of the vacuum container and a covering thereof. An inner cylinder member made of a dielectric material, and a grounding member that is attached to the inside of the vacuum vessel and arranged on the entire circumference of the inner wall, and on which the inner cylinder member is placed. A plasma processing apparatus for processing the sample using generated plasma,
The ground member protrudes from the inner wall surface of the vacuum processing container to the inside of the vacuum processing container and is bent upward from the front portion of the protrusion and the protrusion on which the inner cylinder member is placed, and contacts the plasma. A bent portion,
A plurality of protrusions protruding from the inner wall of the vacuum container located below the upper end of the bending part and above the protrusion between the bent part and the inner wall of the vacuum container; The plasma processing apparatus arrange | positioned between the said bending part and the said projection part. A vacuum processing container made of a conductive material having a substantially cylindrical shape, a sample stage disposed in the vacuum processing container and placing a sample on the upper surface thereof, and covering the inner wall surface with a gap between the inner wall surface of the vacuum container. An inner cylinder member made of a dielectric material, and a grounding member that is attached to the inside of the vacuum vessel and arranged on the entire circumference of the inner wall of the inner cylinder member. A plasma processing apparatus for processing the sample using plasma generated inside,
The ground member protrudes from the inner wall surface of the vacuum processing container to the inside of the vacuum processing container and is bent upward from the front portion of the protrusion and the protrusion on which the inner cylinder member is placed, and contacts the plasma. A bent portion,
Between the bent portion and the inner wall of the vacuum vessel, there is a protruding portion that is located on the entire circumference of the inner wall of the vacuum vessel and is located below the upper end of the bent portion and above the protruding portion. A plasma processing apparatus in which the inner cylinder member is disposed between the bent portion and the protruding portion.

Images