JP6540022B2 - Mounting table and plasma processing apparatus - Google Patents

Description

  The present invention relates to a mounting table used when plasma processing a substrate, and a plasma processing apparatus

  In a manufacturing process of forming a semiconductor circuit on a glass substrate or a semiconductor wafer, there is a process of performing an etching process or a film forming process using plasma. In this process, a substrate is mounted on a mounting table in a vacuum vessel, and high-frequency energy is applied to a processing gas supplied to a space above the mounting table to generate, for example, capacitively coupled plasma or inductively coupled plasma. It will be. The mounting table constitutes a lower electrode which is one electrode of a parallel plate in the case of capacitively coupled plasma, and constitutes a lower electrode to which a bias for attracting ions is applied in the case of inductively coupled plasma. In a plasma processing apparatus performing such a process, a ring-shaped member is provided to surround the mounting table in order to adjust the state of plasma.

  As the material of the ring-shaped member, either conductivity or insulation is selected according to the type of process and the device configuration. For example, a ring member made of an insulating material called a focus ring or the like is used to confine plasma, which is to be spread out of the mounting table, on the substrate. Regarding the mounting structure of the ring member, as described in Patent Document 1, a step corresponding to the thickness of the ring member is provided on the outer periphery of the mounting table, and a so-called flange portion is formed to surround the mounting table. The ring member is fixed to the surface of the flange portion.

  However, since the electrode is positioned on the lower surface side of the ring member, generation of a strong electric field in the vertical direction in the ring member can not be avoided, and ions in the plasma collide with the ring member to scrape the surface of the ring member. And contributed to particle contamination. Although the material of the ring member has been studied in order to weaken the electric field in the vertical direction, it is difficult to effectively suppress the generation of the electric field to effectively reduce the particles.

  Although the mounting base which is not equipped with the flange part is disclosed by patent document 2, plasma may penetrate | invade from between the ring member and the outer peripheral surface of an electrode, and there exists a possibility of producing an abnormal discharge in the outer peripheral surface of an electrode. Also, the width of the ring material is increased, and the vacuum vessel is enlarged.

JP 2007-273685 A JP, 2013-157640, A

  The present invention has been made under the circumstances described above, and an object thereof is to use a mounting table main body on which a substrate is mounted and a ring made of an insulating material surrounding the mounting table main body, which is used when performing plasma processing. It is an object of the present invention to provide a technique capable of reducing particles by suppressing abrasion of a ring member due to a vertical electric field in a mounting table provided with the member.

The mounting table of the present invention is a mounting table provided for mounting the substrate in a vacuum vessel for performing plasma processing on the substrate,
A metal mounting table main body having a mounting surface on which a substrate is mounted, and having no flange on the outer periphery of the mounting surface;
A ring member made of an insulating material provided on the outer periphery of the mounting surface so as to face the plasma processing space to be subjected to the plasma processing and to surround the mounting table main body;
And a side insulating member provided on the lower side of the ring member so as to surround the mounting table main body and fixed in pressure contact with the side peripheral surface of the mounting table main body.
In the mounting table according to the present invention, the mounting table is provided for mounting the substrate in a vacuum vessel for performing plasma processing on the substrate.
A pillar-shaped metal mounting table main body on which a substrate is mounted and side peripheral surfaces from the upper surface to the lower surface are flat;
A ring member made of an insulating material, the upper surface of which faces the plasma processing space to be subjected to the plasma processing, and is provided so as to surround the mounting table main body;
And a side insulating member provided on the lower side of the ring member so as to surround the mounting table main body and fixed in pressure contact with the side peripheral surface of the mounting table main body.

The plasma processing apparatus of the present invention is provided in a vacuum vessel, and the mounting table described above,
A gas supply unit for supplying a processing gas to be plasmatized in the vacuum vessel;
And a plasma generating unit for generating an electric field in the vacuum chamber to plasmatize the processing gas.

  In the present invention, the mounting table main body on which the substrate is mounted has a columnar structure in which the side peripheral surface from the upper surface to the lower surface is flat, and the mounting table main body is surrounded by the lower side of the ring member A side insulating member is provided so as to be in pressure contact with the side peripheral surface of the mounting table main body. Accordingly, since the mounting table main body does not exist directly under the ring member, the electric field in the vertical direction is not generated in the ring member, and the ring member is prevented from being scraped off. Then, on the lower side of the ring member, since the side insulating member is in pressure contact with the side peripheral surface of the mounting table main body, the problem that plasma enters the side peripheral surface of the mounting table main body and causes abnormal discharge is also suppressed. .

1 is a cross-sectional view of a plasma processing apparatus according to an embodiment of the present invention. It is sectional drawing to which a part of mounting base was expanded. It is a top view which shows an insulator and a lower electrode. It is sectional drawing and a top view which show a side insulation member. It is explanatory drawing which shows the electric field direction formed of the conventional mounting base. It is explanatory drawing which shows the electric field direction formed of the mounting base which concerns on embodiment of this invention. It is explanatory drawing explaining the flow of the discharge in a mounting base. It is sectional drawing which shows the mounting base which concerns on the other example of embodiment of this invention.

  A plasma processing apparatus using a substrate mounting table according to an embodiment of the present invention will be described. As shown in FIG. 1, the plasma processing apparatus includes a processing container 10 made of, for example, aluminum or stainless steel, which is grounded. A loading / unloading port 11 for delivering, for example, a rectangular glass substrate G, which is a substrate to be plasma-processed, is provided on the side surface of the processing container 10. It is provided.

In the central portion of the bottom surface of the processing container 10, there is provided a mounting table main body 2 having a rectangular shape in plan view for mounting the glass substrate G and having a flat side peripheral surface from the upper surface to the lower surface. There is. The mounting table main body 2 laminates the lower electrode 20 corresponding to the lower side electrode of the parallel flat plate electrode in this example, and the heat transfer gas diffusion plate 25 made of metal such as aluminum provided on the lower side of the lower electrode 20. Is configured. The heat transfer gas diffusion plate 25 can also be referred to as a lower electrode on the lower side.
The lower electrode 20 is formed of a rectangular metal block made of, for example, aluminum. As shown in FIG. 2, a box-like electrode 201 for a chuck connected to the DC power supply 202 is embedded in the insulating thermal spray film 21 on the upper surface of the lower electrode 20 by an electrostatic attraction force. An electrostatic chuck 200 for holding the glass substrate G is provided. Therefore, the lower electrode 20 can also be called an electrostatic chuck unit. In the drawings after FIG. 3, the description of the electrode 201 and the DC power supply 202 is omitted.

  A high frequency power supply 93 for forming an electric field for plasma generation in the processing container 10 is connected to the lower electrode 20 via a matching unit 94. The high frequency power supply is configured to output, for example, a relatively high frequency, for example, a high frequency of 13.56 MHz. Further, a high frequency power supply 95 for RF bias is electrically connected to the lower electrode 20 through a matching unit 96. The high frequency power supply 95 is configured to output a frequency suitable for controlling the energy of ions drawn into the glass substrate G, for example, a high frequency of 1 to 6 MHz.

For example, an annular chiller channel 22 extending in the circumferential direction is provided inside the lower electrode 20. A heat transfer medium such as Galden (registered trademark) having a predetermined temperature is circulated and supplied to the chiller channel 22 from a chiller unit (not shown), and the glass substrate G on the electrostatic chuck is treated according to the temperature of the heat transfer medium. It can control the temperature. Further, the upper end of the gas supply path 24 provided in the lower electrode 20 is opened on the upper surface of the lower electrode 20, and a heat transfer gas such as He gas is supplied between the upper surface of the lower electrode 20 and the back surface of the glass substrate G. It is configured to be able to. The heat transfer gas is a gas for transferring the heat of the lower electrode 20 to the glass substrate G.
The heat transfer gas diffusion plate 25 includes a flow passage 18 communicating with the lower end of the gas supply passage 24 of the lower electrode 20, and a pipe of heat transfer gas is connected to the flow passage 18. O between the peripheral portion of the upper surface of the heat transfer gas diffusion plate 25 and the lower electrode 20 and between the peripheral portion of the lower surface of the heat transfer gas diffusion plate 25 and the insulating spacer member 28 described later Rings 90 and 91 are provided to intervene. In the drawings after FIG. 3, the description of the O-rings 90 and 91 is omitted.

In addition, raising and lowering pins (not shown) for delivering the glass substrate G between the lower electrode 20 and the external transfer arm penetrate the lower electrode 20 and the heat transfer gas diffusion plate 25 in the vertical direction, It is provided to project from the surface of
On the lower surface side of the heat transfer gas diffusion plate 25 is provided a support column 26 formed of a plurality of columnar insulators for supporting the lower electrode 20 and the heat transfer gas diffusion plate 25. A through hole is provided at the center of the support column 26, and the lower electrode 20 penetrates the bottom from the lower surface side of the processing container 10 and is fixed by a screw 27 inserted into the through hole.

  Further, on the bottom surface of the processing container 10, an insulating spacer member 28 which is a support member for supporting the peripheral portion of the lower electrode 20 over the entire circumference is provided. Between the insulating spacer member 28 and the bottom surface of the processing container 10, an O-ring 92 which is a sealing member for airtight sealing is provided. For this reason, a space of the air atmosphere is formed between the lower side of the mounting table main body 2 and the processing container 10 and the bottom surface.

  A portion of the insulator 3 for suppressing abnormal discharge on the side peripheral surface of the mounting table main body 2 is slightly lower than the upper surface of the lower electrode 20 when an electric field is formed in the processing container 10 around the mounting table main body 2 And the height position of the lower surface of the heat transfer gas diffusion plate 25. FIG. 2 is an enlarged cross-sectional view of the insulator 3, FIG. 3 (a) is a side insulating member 31, and FIG. 3 (b) is a plan view showing the auxiliary insulating member 32. As shown in FIGS. 2 and 3, the insulator 3 is formed in a rectangular ring shape that surrounds the entire periphery of the side surface of the mounting table main body 2, and is a portion on the side in contact with the lower electrode 20 that is the inner side of the insulator 3. And an auxiliary insulating member 32 constituting an outer portion of the side insulating member 31.

  The side insulating member 31 has a flat surface in contact with the lower electrode 20 and the heat transfer gas diffusion plate 25. The surface in contact with the auxiliary insulating member 32 on the opposite side of the surface in contact with the lower electrode 20 and the heat transfer gas diffusion plate 25 in the side insulating member 31 is a vertical first surface 38, the first surface 38 A horizontal second surface 39 extending inward from the lower edge of the surface 38 (the side of the table 2) and a third surface 40 extending vertically downward from the inner edge of the second surface 39 are continuously formed. Are

  The side insulating member 31 is configured by combining, for example, four L-shaped members 4 whose corner portions are located at positions corresponding to the corner portions of the mounting table main body 2 as shown in FIG. . As shown in FIG. 4, each L-shaped member 4 is not a flat surface but has a step shape as viewed from the top, and the end faces of the L-shaped members 4 adjacent to each other are mutually different. It is set to the shape to engage. Then, for example, the ring-shaped side insulating member 31 is configured by combining four L-shaped members 4 so as to form a gap in the length direction at normal temperature (25 ° C.).

  The side insulating member 31 is provided with screw holes 33 and 34 penetrating from the vertical first surface 38 of the outer peripheral surface described above to the inner peripheral surface in contact with the lower electrode 20. The screw hole 33 is formed such that the L-shaped member 4 is fixed in all directions when screwed by the screw 35, and the screw hole 34 is L-shaped when screwed by the screw 35 It is formed as a long hole so that 4 can move in the length direction. As for the arrangement of the screw holes 33 and the screw holes 34, for example, the screw holes 33 are provided at a position closest to the corner of the L-shaped member 4, and the distance from the screw holes 33 toward the end face of the L-shaped member 4 is A plurality of or one screw hole 34 is provided. The side insulating member 31 is pressed against and fixed to the side circumferential surface of the lower electrode 20 by, for example, a metal screw 35 inserted in each of the screw holes 33 and 34. Therefore, even when the L-shaped member 4 expands and contracts in the length direction due to the temperature change, distortion of the fixed portion by the screw 35 and each L-shaped member 4 is suppressed. In each of the screw holes 33 and 34, for example, a lid 300 made of the same material as the side insulating member 31 is closely fitted via an O-ring 301 which is a sealing material so as to cover the head of the screw 35. It is done. Further, the structure for tightly fitting (fitting) the lid portion 300 with each screw hole is not limited to the use of the O-ring 301, and for example, the lid portion 300 may be screwed into the screw hole 33. The screw 35 may be made of an insulating material such as ceramic, and in this case, the lid 300 may not be provided.

  The auxiliary insulating member 32 will be described. The inner side surface of the auxiliary insulating member 32 on the side insulating member 31 side has a shape corresponding to the outer surface of the side insulating member 31 on the auxiliary insulating member 32 side. That is, a vertical surface in contact with the vertical first surface 38 of the side insulating member 31, a horizontal surface in contact with the horizontal second surface 39, and a vertical surface in contact with the third surface continue from the top Form. By fitting the side insulating member 31 on the inner side surface of the auxiliary insulating member 32, the ring-shaped insulator 3 having a rectangular cross section is formed, and the surface where the side insulating member 31 and the auxiliary insulating member 32 contact is It becomes a labyrinth structure that bends halfway.

  Similarly to the side insulating member 31, the auxiliary insulating member 32 is also configured by combining, for example, four L-shaped members 5 having a stepped shape when both ends are viewed from the top as shown in FIG. 3 (b). For example, the ring-shaped auxiliary insulating member 32 is configured by combining four L-shaped members 5 so as to form a gap in the length direction at normal temperature (25 ° C.). As shown in FIG. 2, the auxiliary insulating member 32 is provided with a screw hole 37 penetrating downward from the horizontal surface in contact with the horizontal second surface 39 of the side insulating member 31. As the screw holes 37, like screw holes 33 and 34 in the side insulating member 31, screw holes are used to fix the auxiliary insulating member 32 in all directions by screwing, and L when screwing And a screw hole formed as a long hole so that the V-shaped member 5 can move in the length direction. These screw holes are put together as 37 for convenience. The arrangement relationship of these screw holes in the lateral direction (longitudinal direction) is similar to that of the screw holes 33 and 34 in the side insulating member 31. The auxiliary insulating member 32 is in pressure contact with the insulating spacer member 28 by, for example, a metal screw 36 inserted into each screw hole 37. The screw 36 may be made of an insulating material such as ceramic.

  Although the side insulating member 31 and the auxiliary insulating member 32 are described as being divided into four in order to avoid the complication of the description, in a specific example of the structure, for example, a linear type member etc. It is configured in combination, and the number of divisions is more than four. Then, for example, in the divisions of the side insulation member 31 and the divisions of the auxiliary insulation member 32, the bonding positions of the divisions adjacent to each other are set at predetermined positions. Then, by shifting the screw holes 33 and 34 of the side insulating member 31 and the positions of the screw holes 37 of the auxiliary insulating member 32 in the length direction, the side insulating member 31 and the auxiliary insulating member 32 are as described above. It is assembled in a screwed condition. For example, the auxiliary insulating member 32 may be positioned first, and the assembly in which the side insulating member 31 is in pressure contact with the mounting table main body 2 may be inserted into the region surrounded by the auxiliary insulating member 32. , The mounting table can be assembled.

  A ring made of an insulating material, such as an alumina sintered body, surrounding the lower electrode 20 in a ring shape on the upper surface of the insulator 3, that is, the upper surfaces of the side insulating members 31 and the auxiliary insulating members 32 A focus ring 6 which is a member is provided. Also, it is covered with an outer peripheral insulating member 60 made of, for example, the same material as the focus ring 6 from the outer surface of the insulator 3 to the outer surface of the insulating spacer member 28 and over the entire periphery of the mounting table main body 2 There is.

A shower head 7 is provided on the upper surface of the processing container 10. The shower head 7 is provided with a shower plate 70 in which a large number of gas supply holes 71 are formed to face the mounting surface of the mounting table main body 2. The downstream end of the processing gas supply pipe 74 is connected to the upper side of the shower plate 70 via a gas dispersion chamber 72. In the processing gas supply pipe 74, a processing gas supply source 75, a flow rate adjusting unit 76, and a valve 77 are provided in this order from the upstream side. The shower head 7 is grounded and doubles with the lower electrode 20 as an upper electrode constituting a pair of parallel flat plate electrodes serving as a plasma generating portion. Accordingly, the lower electrode 20, the shower head 7, the matching unit 94, and the high frequency power supply correspond to the plasma generation unit.
Further, at the bottom of the processing container 10, a plurality of exhaust ports 15 are opened at equal intervals over the entire periphery at the edge thereof, and each exhaust port 15 is provided with a vacuum exhaust unit 17 via an exhaust pipe 16. Is provided.

  Subsequently, the operation of the plasma processing apparatus will be described by taking, for example, an etching process as an example. When the plasma processing apparatus operates, the glass substrate G, which is a substrate to be processed, is mounted on the lower electrode 20 by the cooperative action of the external transfer arm and the elevating pins. Next, after the gate valve 13 is closed, a heat transfer gas is supplied between the lower electrode 20 and the glass substrate G and adsorption of the electrostatic chuck is started to hold the glass substrate G.

Then, a process gas containing an etching gas such as CF ₄ or Cl _{2 is} supplied from the shower head 7 into the process vessel 10, and evacuation is performed from the exhaust port 15 to adjust the pressure in the process vessel 10 to a predetermined pressure. . Thereafter, high frequency power for plasma generation is applied from the high frequency power source 93 to the lower electrode 20 through the matching unit 94 to generate a high frequency electric field between the lower electrode 20 and the shower head 7. The processing gas supplied into the processing container 10 is excited by a high frequency electric field generated between the lower electrode 20 and the shower head 7 to generate plasma of the processing gas. Further, ions contained in the plasma are attracted to the lower electrode 20 from the high frequency power supply 95, and the film to be processed of the glass substrate G is etched.

  Since the focus ring 6 made of an insulating material is provided around the mounting table main body 2, plasma around the mounting table main body 2 tends to be focused on the mounting table main body 2 side, whereby the peripheral edge of the glass substrate G The reduction of plasma density in the FIG. 5 shows a conventional structure in which the flange 81 is formed on the mounting table main body 2, but in this case, the flange 81 which is a metal body exists below the focus ring 6. For this reason, there is a concern that the surface of the focus ring 6 is exposed to a strong electric field in the vertical direction, and may be scraped by active species in the plasma. In the figure, reference numeral 82 denotes a screw for fixing the focus ring 6 and the lower electrode 80, and reference numeral 83 denotes a cover for covering the head of the screw 82 for fixing the focus ring 6.

  On the other hand, in the above embodiment, as shown in FIGS. 1 and 2, the side peripheral surface of the mounting table main body 2 including the lower electrode 20 is a flat surface from the upper surface to the lower surface, and no flange is provided. . Therefore, as shown in FIG. 6, it becomes difficult to form a strong electric field in the vertical direction on the surface of the focus ring 6, so that the collision of active species in the plasma with the surface of the focus ring 6 is suppressed and the abrasion of the focus ring 6 is suppressed. And the generation of particles can be suppressed. Furthermore, since the electric field in the vertical direction with respect to the focus ring 6 is suppressed, power loss can be reduced.

  Further, the advantages of the side insulation member 31 and the auxiliary insulation member 32 will be described. The outer peripheral surface of the electrostatic chuck unit which is the lower electrode 20 is covered with the thermal spray film 21, but the outer peripheral surface of the heat transfer gas diffusion plate 25 stacked under the lower electrode 20 is covered with the thermal spray film 21. No, the metal surface is bare or anodized. Therefore, plasma tends to go to the outer peripheral surface of the heat transfer gas diffusion plate 25. A thick line shown in FIG. 7 indicates a path toward the outer peripheral surface of the heat transfer gas diffusion plate 25 with plasma.

  Since the shorter the path is, the more easily the plasma infiltrates, the path in which the plasma is most likely to infiltrate is a path P1 which is a gap between the side insulating member 31 and the lower electrode 20. However, since the side insulating member 31 is in pressure contact with the side peripheral surface of the lower electrode 20, it is difficult to see the outer peripheral surface of the heat transfer gas diffusion plate 25 from the plasma space through the path P1. For this reason, the plasma passes a path P2 from the focus ring 6 and the lower electrode 20 or the outer peripheral insulating member 60 to the heat transfer gas diffusion plate 25 via the side insulating member 31 and the auxiliary insulating member 32. However, since the labyrinth structure is provided between the side insulation member 31 and the auxiliary insulation member 32, the heat transfer gas diffusion plate 25 is difficult to see from the plasma space also on the path P2.

  Further, the path P3 extending from between the focus ring 6 and the outer peripheral insulating member 60, between the outer peripheral insulating member 60 and the auxiliary insulating member 32, and along the surface of the insulating spacer member 28 toward the heat transfer gas diffusion plate 25 Since the auxiliary insulating member 32 is in pressure contact with the insulating spacer member 28 by the screw 36, it is difficult for the plasma to penetrate. Therefore, occurrence of abnormal discharge on the outer peripheral surface of the heat transfer gas diffusion plate 25 where the thermal spray film 21 is not formed can be suppressed.

In the embodiment described above, the mounting table main body 2 on which the glass substrate G is mounted has a columnar structure in which the side peripheral surface from the upper surface to the lower surface is flat, and the mounting table main body below the focus ring 6 The side insulating member 31 is provided so as to surround 2 and to be in pressure contact with the side peripheral surface of the mounting table main body 2. Therefore, since the mounting table main body 2 does not exist directly under the focus ring 6, the electric field in the vertical direction is not generated in the focus ring 6, and the abrasion of the focus ring 6 can be suppressed. Further, the side insulating member 31 is in pressure contact with the side peripheral surface of the lower electrode 20, and the auxiliary insulating member 32 is in pressure contact with the insulating spacer member 28, and the gap between the side insulating member 31 and the auxiliary insulating member 32 is a labyrinth structure. ing. Accordingly, abnormal discharge in the heat transfer gas diffusion plate 25 below the lower electrode 20 can be suppressed.
Further, concave and convex portions engaging with each other are provided on the lower surface side of the focus ring 6 and the upper surface side of the insulator 3 or the outer peripheral insulating member 60, and the focus ring 6 is engaged with the insulator 3 or the outer peripheral insulating member 60. It may be configured to be fixed.

  Moreover, as a mounting base which concerns on the other example of embodiment of this invention, it is not restricted to providing the chiller flow path which is a temperature control flow path in the electrostatic chuck unit which is the lower electrode 20 like previous embodiment. . For example, as shown in FIG. 8, the chiller channel may not be provided in the electrostatic chuck unit that is the lower electrode 100 on the upper side, and the chiller channel 102 may be provided on the lower electrode 101 on the lower side. In this case, the lower electrode 100 on the upper side is made of, for example, SUS (stainless steel), and the lower electrode 101 on the lower side is made of, for example, aluminum. Also in the case of such a configuration, the same effect as in the previous embodiment can be obtained, and abnormal discharge in the lower electrode 101 on the lower side can be suppressed.

  Moreover, while providing the recessed part which an opening part is circular and the back side is expanded on the outer peripheral surface of the lower electrode 20, the convex part of the shape corresponding to a recessed part is provided in the side insulation member 31, and it mutually makes pressure contact Good. In this case, the side insulating member 31 is in pressure contact with the lower electrode 20 by providing a spring having an elastic force in the circumferential direction so that the opening faces the back of the recess and inserting the protrusion into the recess so as to expand the spring. It will be in the

  Further, the mounting table main body 2 is not limited to a prism, but may be a cylinder. Furthermore, that the side peripheral surface of the mounting table main body 2 is flat does not mean only a completely flat surface, and even if there are slight irregularities such that the effects of the present invention can be substantially obtained, Even if it is slightly inclined, it is included in the meaning of "flat surface".

  Furthermore, the plasma processing apparatus according to the present invention is not limited to the parallel plate type, and for example, an electric field and a magnetic field induced by supplying high frequency power to an antenna provided on the ceiling of a vacuum vessel are applied to the processing gas to generate plasma. The present invention can also be applied to an ICP (Inductive Coupled Plasma) plasma processing apparatus to be generated. That is, the plasma is not limited to the capacitive coupling type and may be an inductive coupling type. The plasma processing is not limited to etching, and may be plasma film formation processing for forming a film on a substrate. The mounting table main body 2 is not limited to an electrode. For example, in the induction plasma processing apparatus, the effect of the present invention can be obtained even if it is a metal column not connected to a power supply.

Further, although the side insulating members 31 and the auxiliary insulating members 32 are respectively configured by combining the L-shaped members 4 and 5, they may be combined with linear members. Also in this case, by combining the screw hole movable in all directions with respect to the screw and the screw hole movable in the longitudinal direction as described above, the thermal expansion of each of the side insulation member 31 and the auxiliary insulation member 32 is absorbed It may be configured to be able to.
Furthermore, the present invention is not limited to the plasma processing apparatus for plasma processing the glass substrate G, but may be a plasma processing apparatus for plasma processing a disk-shaped wafer of, for example, 300 mm in diameter.

Reference Signs List 2 mounting table main body 3 insulator 6 focus ring 10 processing vessel 20, 100 lower electrode 21 thermal spray film 25 heat transfer gas diffusion plate 28 insulating spacer member 31 side insulating member 32 auxiliary insulating member 35, 36 screw G glass substrate

Claims (12)

In a mounting table provided for mounting the substrate in a vacuum vessel for performing plasma processing on the substrate,
A metal mounting table main body having a mounting surface on which a substrate is mounted, and having no flange on the outer periphery of the mounting surface;
A ring member made of an insulating material provided on the outer periphery of the mounting surface so as to face the plasma processing space to be subjected to the plasma processing and to surround the mounting table main body;
And a side insulating member provided on the lower side of the ring member so as to surround the mounting table main body, and fixed in pressure contact with the side peripheral surface of the mounting table main body. .   The mounting base according to claim 1, wherein the side insulating member is tightened by a screw member from an outer peripheral surface side toward a side peripheral surface of the mounting table main body. The screw member is made of metal,
A head portion of the screw member is disposed in a screw hole of the side insulating member;
The said screw hole is covered by the cover part of the insulating material, The mounting base of Claim 2 characterized by the above-mentioned.   The said screw member is an insulating material, The mounting base of Claim 2 characterized by the above-mentioned.   The auxiliary insulating member according to claim 3 or 4, wherein the auxiliary insulating member is provided in surface contact with the outer peripheral surface of the side insulating member so that the arrangement region of the screw member can not be seen from the outer peripheral surface. Mounting table. The mounting table according to claim 5, wherein a gap between the side insulation member and the auxiliary insulation member is configured to form a labyrinth as viewed from the plasma processing space. The outer peripheral surface of the side insulating member is, in order from the upper side, a first surface parallel to the side peripheral surface of the mounting table main body, a second surface perpendicular to the side peripheral surface, parallel to the side peripheral surface The third surface is continuous and the first surface is located outside the second surface,
7. The auxiliary insulating member according to claim 6, wherein the auxiliary insulating member is tightened by a screw member from a surface in surface contact with the second surface to a support member supporting the auxiliary insulating member from the lower side. Mounting table. In a mounting table provided for mounting the substrate in a vacuum vessel for performing plasma processing on the substrate,
A pillar-shaped metal mounting table main body on which a substrate is mounted and side peripheral surfaces from the upper surface to the lower surface are flat;
A ring member made of an insulating material, the upper surface of which faces the plasma processing space to be subjected to the plasma processing, and is provided so as to surround the mounting table main body;
And a side insulating member provided on the lower side of the ring member so as to surround the mounting table main body, and fixed in pressure contact with the side peripheral surface of the mounting table main body. . The side insulating member is tightened by a screw member from the outer peripheral surface toward the side peripheral surface of the mounting table main body,
An auxiliary insulating member is provided so as to be in surface contact with the outer peripheral surface of the side insulating member so that the region where the screw member is disposed can not be seen from the outer peripheral surface,
The mounting table according to claim 8, wherein a gap between the side insulation member and the auxiliary insulation member is configured to form a labyrinth as viewed from the plasma processing space. The upper side of the mounting table main body is constituted by an electrostatic chuck whose upper surface and side peripheral surface are coated with an insulating sprayed film,
The surface of the side insulating member in pressure contact with the side peripheral surface of the mounting table main body is a portion not covered with the sprayed film, which is located below the portion covered by the sprayed film. The mounting table according to any one of claims 1 to 9, wherein the mounting table is extended. The mounting table according to any one of claims 1 to 10 provided in a vacuum vessel,
A gas supply unit for supplying a processing gas to be plasmatized in the vacuum vessel;
And a plasma generating unit for generating an electric field in the vacuum chamber to plasmatize the processing gas. The mounting table body, a plasma processing apparatus according to claim 11, characterized in that it is fixed by a screw member passing through the bottom surface of the vacuum vessel from the lower surface side of the vacuum vessel.

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