JP5893516B2 - Processing apparatus for processing object and mounting table for processing object - Google Patents

Description

  The present invention relates to a processing apparatus and a mounting table for plasma processing an object to be processed.

  In the manufacture of semiconductor devices, for example, a plasma processing apparatus is used that performs fine processing such as etching or film formation on a target object such as a semiconductor wafer (hereinafter referred to as “wafer”) by the action of plasma.

  A mounting table for mounting an object to be processed such as a wafer is installed in the processing container of the plasma processing apparatus described above. Conventionally, this mounting table includes a susceptor functioning as a lower electrode, an electrostatic chuck for mounting a wafer provided on the upper surface of the susceptor, and a focus ring made of, for example, silicon provided on an outer peripheral portion of the electrostatic chuck. Has been. In plasma processing of the wafer placed on the electrostatic chuck, high frequency power is applied to the susceptor to generate plasma in the processing container. At this time, the generated plasma converges on the wafer by the action of the focus ring, and the wafer is subjected to uniform plasma processing.

  By the way, the temperature of the focus ring affects the etching characteristics of the outer peripheral portion of the wafer. Therefore, normally, the susceptor is cooled by circulating a refrigerant through the susceptor, and the focus ring is cooled by heat transfer from the electrostatic chuck provided on the upper surface of the susceptor. At this time, it is necessary to cool the focus ring uniformly.

  Therefore, for example, in Patent Document 1, as shown in FIG. 5, for example, a heat transfer medium 203 is interposed between the focus ring 201 and the electrostatic chuck 202 of the mounting table 200, and the focus ring 201 is further attached to the electrostatic chuck. It has been proposed to provide pressing means 210 that presses against 202 and fixes.

  The pressing unit 210 includes, for example, a pressing member 211 that presses the outer peripheral surface 201 a of the focus ring 201 downward, and a screw member 212 that fastens the pressing member 211 to the electrostatic chuck 202. The pressing member 211 is made of alumina, for example, and is covered with a cover 213 made of, for example, quartz for preventing the pressing member 211 from being sputtered by plasma. Thereby, heat transfer between the focus ring 201 and the electrostatic chuck 202 can be made uniform while preventing damage to the pressing member 211 due to plasma.

JP 2002-16126 A

  However, the region above the focus ring 201 is a region where plasma is generated. Therefore, a portion of the cover 213 that covers the pressing member 211 that presses the focus ring 201, particularly near the focus ring 201, is sputtered by plasma. Then, the impedance changes due to the pressing member 211 being exposed, and the apparent area of the electrostatic chuck 202 as an electrode increases. As a result, there arises a problem that the plasma distribution in the processing vessel changes with time. In that case, it is difficult to process the object to be processed uniformly in the surface.

  In order to avoid such a problem, it is conceivable that the cover 213 is moved away from the plasma region by arranging the pressing member 211 as close to the outer peripheral end of the focus ring 201 as possible. However, if the pressing force is concentrated on the outer peripheral surface 201 a provided at the outer peripheral end of the focus ring 201, a moment is applied to the focus ring 101. As a result, the focus ring 201 is distorted and the central portion of the electrostatic chuck 202 is lifted, and heat transfer with the electrostatic chuck 202 is not uniform, so that it is difficult to use such a method.

  The present invention has been made in view of such points, and an object of the present invention is to provide a mounting table and a processing apparatus for a target object capable of suppressing a change in plasma distribution over time and processing the target object uniformly in a plane. It is said.

To achieve the above object, the present invention provides a processing apparatus for an object to be processed, comprising a processing container that defines a processing space, and a mounting table disposed in the processing space, wherein the mounting table is An electrostatic chuck for mounting the object to be processed; a focus ring provided on an outer periphery of the electrostatic chuck; and an annular pressing member that presses the focus ring against the electrostatic chuck; A fixing member that fixes the pressing member to the electrostatic chuck, and the focus ring is formed with a locking portion that is recessed toward the center of the focus ring over the entire outer periphery. pressing member, a plurality of arc-shaped members are formed by combining the ring, a contact portion for pressing the focus ring engaged with the engagement portion of the focus ring to the electrostatic chuck, whether the contact portion An installation portion that extends downward and is fixed to the electrostatic chuck by the fixing member, so that the contact portion of the pressing member does not enter the field of view in a plan view on the upper surface of the outer peripheral end portion of the focus ring. It is characterized in that a heel part is formed to cover.

  According to the present invention, the contact portion of the pressing member is locked to the locking portion of the focus ring to press the focus ring against the electrostatic chuck, and is the outer peripheral end of the focus ring and above the locking portion. Is formed with a collar portion that covers the contact portion so as not to enter the field of view in plan view. Therefore, the contact portion is not exposed to the plasma region side. Therefore, unlike the conventional case, since the cover that covers the pressing member is sputtered and the pressing member is exposed, the impedance does not change with time, so that the time-dependent change in plasma distribution in the processing vessel is suppressed. be able to. Further, since the locking portion of the focus ring is formed so as to be recessed in the center direction of the focus ring, compared with the case where the outer peripheral end of the conventional focus ring is pressed, The center side of the electrostatic chuck can be pressed. Therefore, it is possible to suppress the focus ring from being distorted by the moment and the temperature distribution of the focus ring from varying.

  The installation portion of the pressing member may be covered with a covering member made of quartz.

The covering member is provided in contact with the outer peripheral end of the flange portion of the focus ring,
A shielding member may be provided between the covering member and the installation portion so as to prevent the installation portion from entering the field of view from a boundary between the flange portion of the focus ring and the covering member in a plan view. .

  A heat transfer member may be interposed between the electrostatic chuck and the focus ring.

  The pressing member may be formed of ceramics.

According to another aspect of the present invention, there is provided a mounting table for an object to be processed disposed in a plasma processing container, comprising: an electrostatic chuck for mounting the object to be processed; and a focus ring provided on an outer peripheral portion of the electrostatic chuck. An annular pressing member that presses the focus ring against the electrostatic chuck, and a fixing member that fixes the pressing member to the electrostatic chuck. A locking portion that is recessed in the central direction of the focus ring is formed over the entire circumference of the focus ring, and the pressing member is formed by combining a plurality of circular arc members in an annular shape, and is engaged with the locking portion of the focus ring. A contact portion that stops and presses the focus ring against the electrostatic chuck, and an installation portion that extends downward from the contact portion and is fixed to the electrostatic chuck by the fixing member Comprising a, on the upper surface of the outer peripheral end portion of the focus ring is characterized in that the visor portion for covering so that the contact portion of the pressing member does not fall within the field of view in a plan view is formed.

  According to the present invention, it is possible to suppress the change of the plasma distribution with time and to uniformly treat the object to be processed.

It is a longitudinal cross-sectional view which shows the outline of a structure of the plasma processing apparatus concerning this Embodiment. It is a longitudinal cross-sectional view which shows the outline of a structure of the focus ring vicinity in the mounting base concerning this Embodiment. It is the perspective view which looked at a focus ring, a press member, and a support member from diagonally downward. It is a longitudinal cross-sectional view which shows the outline of a structure of the focus ring vicinity in the mounting base concerning other embodiment. It is a longitudinal cross-sectional view which shows the outline of a structure of the focus ring vicinity of the conventional mounting base.

  Hereinafter, an example of an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a longitudinal sectional view showing a schematic configuration of a processing apparatus 1 according to an embodiment of the present invention. A processing apparatus 1 shown in FIG. 1 is a parallel plate type plasma processing apparatus.

  The plasma processing apparatus 1 has a substantially cylindrical processing container 16 provided with a mounting table 2 on which a wafer W, which is a silicon substrate as an object to be processed, is mounted. The processing container 16 is electrically connected to the ground line 17 and grounded. Further, the inner wall of the processing vessel 16 is covered with a liner (not shown) having a thermal spray coating made of a plasma resistant material on the surface.

  The mounting table 2 includes a substantially disc-shaped electrostatic chuck 11, a substantially annular focus ring 10, and a pressing member 12 that presses the focus ring 10 against the electrostatic chuck. The electrostatic chuck 11 is a substantially disk-shaped member, and is formed, for example, by sandwiching an electrode for electrostatic chuck between a pair of ceramics.

  The lower surface of the electrostatic chuck 11 is supported by a susceptor 13 as a lower electrode. The susceptor 13 is formed in a substantially disk shape from a metal such as aluminum. A support base 15 is provided at the bottom of the processing container 16 via an insulating plate 14, and the susceptor 13 is supported on the upper surface of the support base 15. An electrode (not shown) is provided inside the electrostatic chuck 11 so that the wafer W can be attracted and held by an electrostatic force generated by applying a DC voltage to the electrode.

  The focus ring 10 for improving the uniformity of the plasma processing is formed of conductive silicon made of, for example, silicon, and is disposed on the outer surface of the electrostatic chuck 11 on the upper surface of the susceptor 13. A pressing member 12 for pressing the focus ring 10 against the electrostatic chuck 11 is provided below the focus ring 10. The outer surface of the susceptor 13 and the support base 15 is covered with a cylindrical member 51 made of, for example, quartz. Details of the vicinity of the focus ring 10 will be described later.

  A coolant channel 15a through which a coolant flows is provided, for example, in an annular shape inside the support base 15, and is held by the electrostatic chuck 11 by controlling the temperature of the coolant supplied by the coolant channel 15a. The temperature of the wafer W can be controlled. Further, a heat transfer gas pipe 22 for supplying, for example, helium gas as a heat transfer gas between the electrostatic chuck 11 and the wafer W held by the electrostatic chuck 11 includes, for example, the bottom of the processing vessel 16, the susceptor 13, The support base 15 and the insulating plate 14 are provided through.

  The susceptor 13 is electrically connected via a first matching unit 31 to a first high frequency power supply 30 for supplying high frequency power to the susceptor 13 to generate plasma. The first high frequency power supply 30 is configured to output a high frequency power of, for example, 27 to 100 MHz, for example, 100 MHz in the present embodiment. The first matching unit 31 matches the internal impedance of the first high-frequency power source 30 with the load impedance, and when the plasma is generated in the processing container 16, the internal impedance of the first high-frequency power source 30. And the load impedance appear to coincide with each other.

  The susceptor 13 is provided with a second high-frequency power supply 40 for supplying ions to the wafer W by supplying a high-frequency power to the susceptor 13 and applying a bias to the wafer W via a second matching unit 41. Are electrically connected. The second high frequency power supply 40 is configured to output a high frequency power of 400 kHz to 13.56 MHz, for example, 3.2 MHz in the present embodiment, for example. Similar to the first matching unit 31, the second matching unit 41 matches the internal impedance of the second high-frequency power source 40 with the load impedance.

  The first high-frequency power source 30, the first matching unit 31, the second high-frequency power source 40, and the second matching unit 41 are connected to a control unit 150 described later, and these operations are controlled by the control unit 150. Is done.

  Above the susceptor 13, which is the lower electrode, an upper electrode 42 is provided in parallel to face the susceptor 13. The upper electrode 42 is supported on the upper portion of the processing container 16 via a conductive holding member 58. Therefore, the upper electrode 42 is at a ground potential in the same manner as the processing container 16.

  The upper electrode 42 includes an electrode plate 56 that forms a surface facing the wafer W held by the electrostatic chuck 11, and an electrode support 57 that supports the electrode plate 56 from above. In the electrode plate 56, a plurality of gas supply ports 53 for supplying a processing gas into the processing container 16 are formed so as to penetrate the electrode plate 56. The electrode plate 56 is made of, for example, a low-resistance conductor or semiconductor with low Joule heat, and silicon is used in the present embodiment, for example. The electrode support plate 57 is made of a conductor, and aluminum is used in this embodiment, for example.

  A gas diffusion chamber 54 formed in a substantially disk shape is provided in the center portion inside the electrode support 57. A plurality of gas holes 55 extending downward from the gas diffusion chamber 54 are formed in the lower part of the electrode support 57, and the gas supply port 53 is connected to the gas diffusion chamber 54 through the gas hole 55.

  A gas supply pipe 72 is connected to the gas diffusion chamber 54. A processing gas supply source 73 is connected to the gas supply pipe 72 as shown in FIG. 1, and the processing gas supplied from the processing gas supply source 73 is supplied to the gas diffusion chamber 54 via the gas supply pipe 72. Is done. The processing gas supplied to the gas diffusion chamber 54 is introduced into the processing container 16 through the gas hole 55 and the gas supply port 53. That is, the upper electrode 42 functions as a shower head that supplies the processing gas into the processing container 16.

  The gas supply source 73 in this embodiment includes an etching gas supply unit 73a that supplies a processing gas for etching processing. The gas supply source 73 includes a valve 74 provided between the gas supply unit 32 a and the gas diffusion chamber 54 and a flow rate adjusting mechanism 75. The flow rate of the gas supplied to the gas diffusion chamber 54 is controlled by the flow rate adjusting mechanism 75.

  For example, CF 4 gas or oxygen gas is used as an etching gas for the etching process.

  At the bottom of the processing container 16, an exhaust channel 85 that functions as a channel for discharging the atmosphere in the processing container 16 to the outside of the processing container 16 by the inner wall of the processing container 16 and the outer surface of the cylindrical member 51. Is formed. An exhaust port 90 is provided on the bottom surface of the processing container 16. An exhaust chamber 91 is formed below the exhaust port 90, and an exhaust device 93 is connected to the exhaust chamber 91 via an exhaust pipe 92. Therefore, by driving the exhaust device 93, the atmosphere in the processing container 16 can be exhausted through the exhaust passage 85 and the exhaust port 90, and the inside of the processing container can be decompressed to a predetermined degree of vacuum.

  A ring magnet 100 is arranged around the processing container 16 so as to be concentric with the processing container 16. The ring magnet 100 can apply a magnetic field to the space between the electrostatic chuck 11 and the upper electrode 42. The ring magnet 100 is configured to be rotatable by a rotation mechanism (not shown).

  The plasma processing apparatus 1 is provided with the control unit 150 as described above. The control unit 150 is, for example, a computer and has a program storage unit (not shown). The program storage unit also stores a program for operating the plasma processing apparatus 120 by controlling the power supplies 30 and 40, the matching units 31 and 41, and the flow rate adjusting mechanisms 74a.

  The above program is recorded on a computer-readable storage medium such as a computer-readable hard disk (HD), flexible disk (FD), compact disk (CD), magnetic optical desk (MO), or memory card. May have been installed in the control unit 150 from the storage medium.

  Next, the configuration in the vicinity of the focus ring 10 in the mounting table 1 will be described in detail. As shown in FIG. 2, the outer peripheral edge portion 11 a on the upper surface of the electrostatic chuck 11 is formed to be one step lower than the surface of the electrostatic chuck 11 on which the wafer W is placed. An annular heat transfer member 80 is disposed on the upper surface of the step-shaped outer peripheral edge portion 11 a, and the focus ring 10 is disposed on the upper surface of the heat transfer member 80. The heat transfer member 80 is formed of a flexible heat-resistant member such as silicon rubber.

  On the outer surface of the focus ring 10, a locking portion 10 a that is recessed toward the center of the focus ring 10 is formed over the entire circumference of a region near the center of the focus ring 10 in the thickness direction. Further, the locking portion 10 a is located approximately near the center of the focus ring 10 in the width direction. The end of the focus ring 10 on the electrostatic chuck 11 side is slightly lower than the upper surface of the electrostatic chuck 11. The outer peripheral edge of the wafer W on the electrostatic chuck 11 protrudes from this lowered portion. Further, the upper surface of the focus ring 10 is gradually increased toward the outer peripheral side of the electrostatic chuck 11. A portion that is higher than the upper surface of the electrostatic chuck 11 extends outward in the diameter direction of the focus ring 10, and is formed as a flange portion 10 b that projects outward from the outer peripheral end portion of the electrostatic chuck 11 in plan view. ing. The lower surface side of the focus ring 10 is formed to be shorter than the center side of the focus ring 10 than the flange portion 10b, that is, shorter than the flange portion 10b.

  As shown in FIG. 2, the pressing member 12 includes a contact portion 12 a that is locked to the locking portion 10 a of the focus ring 10, and an installation portion 12 b that extends downward from the contact portion 12 a. The pressing member 12 is made of, for example, ceramics. An annular support member 50 made of, for example, ceramics is disposed on the lower surface of the installation portion 12b. A cylindrical member 51 made of, for example, quartz is provided below the support member 50 and on the outer surfaces of the electrostatic chuck 11 and the susceptor 13. As the pressing member 12 and the support member 50, for example, alumina or the like can be used.

  The upper end portion of the contact portion 12 a extends horizontally toward the center direction of the electrostatic chuck 11. Then, the contact portion 12 a is locked to the locking portion 10 a of the focus ring 10 by fitting the tip portion of the contact portion 12 a on the focus ring 10 side into the locking portion 10 a of the focus ring 10. Further, the upper surface of the contact portion 12a is covered with the flange portion 10b of the focus ring 10, so that the contact portion 12a does not enter the field of view when viewed from above the focus ring 10.

  The upper surface of the installation part 12b is lower than the locking part 10a of the focus ring 10, for example. A through hole is formed in the installation portion 12 b, and the pressing member 12 is fixed to the support member 50 by, for example, a screw 52 as a fixing member provided through the through hole. Then, by pressing the pressing member 12 toward the cylindrical member 51 with the screw 52, the focus ring 10 that engages with the contact portion 12a is pressed into the electrostatic chuck 11 side. Further, when the focus ring 10 is pushed to the electrostatic chuck 11 side, the focus ring 10 comes into close contact with the heat transfer member 80 provided on the upper surface of the outer peripheral edge portion 11a, and the heat between the focus ring 10 and the electrostatic chuck 11 is obtained. Improves transmission.

  As shown in FIG. 3, for example, the pressing member 12 is formed by combining two arc-shaped arc members 60 in an annular shape. When the contact portion 12a and the locking portion 10a of the focus ring 10 are locked, the divided pressing member 12, that is, the contact portion 12a of the arc member 60 is moved from the outside of the locking portion 10a to the locking portion 10a. Fit. The installation portion 12b of the pressing member 12 fitted to the focus ring 10 is fixed to the support member 50 with the screw 52 as described above. In FIG. 3, the case where the pressing member 12 is configured by two arc members 60 is illustrated. However, the number of divisions of the pressing member 12 is not limited to the present embodiment, and is arbitrary. Can be set. Further, in FIG. 3, the support member 50 is depicted in a state of being formed in an integral annular shape, but the support member 50 may be divided into two or more, for example.

  A shielding member 61 made of, for example, quartz is provided on the upper surface of the installation portion 12a and the screw 52. This shielding member 61 is also formed by combining members divided into a plurality of rings. The installation part 12a and the screw 52 are covered with the shielding member 61 so that they cannot be seen from above the shielding member 61 in plan view. Further, the inner peripheral surface of the shielding member 61, in other words, the end portion on the electrostatic chuck 11 side is located below the flange portion 10 b of the focus ring 10.

  Further, an annular covering member 70 made of, for example, quartz is provided on the upper surface of the shielding member 61. As shown in FIG. 2, the covering member 70 is provided in contact with the outer peripheral end of the flange portion 10 b of the focus ring 10 as shown in FIG. 2. Thereby, from the boundary between the covering member 70 and the flange portion 10b, the shielding member 61 only enters the field of view in a plan view, and the pressing member 12 and the screw 52 do not enter the field of view. Thereby, it can prevent that the screw | thread 52 and the press member 12 receive a damage with the plasma which penetrate | invaded from the boundary of the coating | coated member 70 and the collar part 10b.

  On the outer surface of the pressing member 12, which is the lower surface of the covering member 70, a stepped member 71 whose upper surface falls stepwise toward the outer peripheral portion is disposed. The lower surface of the covering member 70 is formed in a stepped shape that descends in the outer peripheral direction along the upper surface of the stepped member 71. The stepped member 71 is supported on the upper surface of the cylindrical member 51. Thereby, a predetermined gap is formed in a step shape between the covering member 70 and the stepped member 71, and this gap functions as a labyrinth seal. Therefore, it becomes difficult for plasma to enter the gap, and damage to the boundary surfaces of the shielding member 61 and the pressing member 12 from the plasma is suppressed.

  The plasma processing apparatus 1 and the mounting table 2 according to the present embodiment are configured as described above. Next, for example, the operation of the processing apparatus 1 and the mounting table 2 in the plasma etching process will be described.

  In the plasma etching process, the wafer W is first placed and held on the electrostatic chuck 11. Next, a processing gas for etching is supplied from the gas supply source 72 into the processing container 16. Thereafter, high frequency power is continuously applied to the susceptor 13 as the lower electrode by the first high frequency power supply 30 and the second high frequency power supply 40, and a high frequency electric field is formed between the upper electrode 42 and the electrostatic chuck 11. Is done. As a result, plasma is generated in the processing container 16 and the object to be processed is etched by radicals (for example, oxygen radicals or fluorine radicals) of elements contained in the processing gas.

  The plasma in the processing container 1 converges above the wafer W by the focus ring 10 on the electrostatic chuck 11, and a predetermined process is performed on the surface of the wafer W. At this time, although the temperature of the wafer W and the focus ring 10 rises due to the influence of plasma, the wafer W and the focus ring 10 are cooled by the refrigerant flowing through the refrigerant passage 15a of the support base 15. Further, since the focus ring 10 is pressed by the pressing member 12 and is in close contact with the heat transfer member 80 disposed on the outer peripheral edge portion 11a of the electrostatic chuck 11, it is efficiently cooled and uniformly cooled without temperature unevenness. The

  Further, since the focus ring 10 is pressed by the contact portion 12a of the pressing member 12 locked to the locking portion 10a, for example, this pressing force acts on a position near the center of the focus ring 10 in the width direction. In this case, the moment applied to the focus ring 10 is extremely small as compared with the case where the outer peripheral end is pressed as in the conventional focus ring 101 shown in FIG. Therefore, distortion of the focus ring 10 is suppressed, and heat transfer with the electrostatic chuck 11 becomes more uniform. As a result, the temperature of the focus ring 10 becomes more uniform and stable plasma processing is performed.

  When the plasma treatment is repeated continuously, the covering member 70 is sputtered by the plasma and damaged. However, since the contact portion 12a of the pressing member 12 is covered with the flange portion 10b of the focus ring 10, even when the covering member 70 is damaged, the contact portion 12a is not exposed to the plasma region. Moreover, since the installation part 12b of the pressing member 12 is also covered with the shielding member 61, exposure of the installation part 12b to the plasma region can be prevented. As a result, even if the covering member 70 is damaged, the impedance does not change, so that the plasma treatment can be performed stably without the plasma distribution changing over time.

  According to the above embodiment, the contact portion 12a of the pressing member 12 is locked to the locking portion 10a of the focus ring 10, and the contact portion 12a is covered by the flange portion 10b formed above the locking portion 10a. Therefore, even if the covering member 70 is damaged by the plasma, the contact portion 12a is not exposed to the plasma region. Moreover, since the installation part 12b of the pressing member 12 is also covered with the shielding member 61, the installation part 12b can be prevented from being exposed to the plasma region. Therefore, it is possible to suppress a change in impedance when the covering member 70 is damaged, and it is possible to minimize fluctuations in plasma distribution over time. As a result, it is possible to suppress the change in the plasma distribution over time and treat the object to be processed uniformly in the surface. Furthermore, the lifetime of the pressing member 12 is extended by preventing the pressing member 12 from being exposed to the plasma region. In addition, since the installation part 12b is located below the contact part 12a, even if the installation part 12b is exposed to the plasma region, the influence on the change in impedance can be reduced.

  In addition, since the focus ring 10 is depressed in the concave locking portion 10a in the direction of the electrostatic chuck 11 by the pressing member 12, compared with the conventional case where the outer peripheral end of the focus ring 101 is pressed. The moment applied to the focus ring 10 becomes extremely small. Therefore, distortion of the focus ring 10 is suppressed, and heat transfer with the electrostatic chuck 11 becomes more uniform. As a result, the temperature of the focus ring 10 becomes more uniform, and stable plasma processing can be performed. In order to reduce the moment applied to the focus ring 10 when the focus member 10 is pressed in the direction of the electrostatic chuck 11 with the pressing member 12, the locking portion 10 a is set near the center of the focus ring 10 in the width direction, or It is preferable to form it at a position on the center side of the electrostatic chuck 11.

  Further, according to the embodiment described above, the inner peripheral surface of the covering member 70 is provided in contact with the outer peripheral end of the flange portion 10b of the focus ring 10, and below the boundary between the covering member 70 and the flange portion 10b. Since the shielding member 61 is provided and the stepped member 71 is disposed on the lower surface of the covering member 70, a labyrinth seal is formed between the covering member 70 and the shielding member 61 or the stepped member 71. Therefore, the labyrinth seal makes it difficult for plasma to enter the gaps between the members, and damage to the boundary surfaces of the shielding member 61 and the pressing member 12 from the plasma can be suppressed.

  In the above embodiment, since the pressing member 12 is composed of a plurality of arc members 60, the pressing member 12 can be easily replaced.

  In the above embodiment, the tip of the flange portion 10b is projected outward from the outer peripheral end portion of the electrostatic chuck 11. However, the shape of the flange portion 10b is not limited to this embodiment. The shape of the flange portion 10b may be such that the contact portion 12a is covered with the flange portion 10b in a plan view in relation to the contact portion 12a of the pressing member 12, and the outer peripheral edge portion 11a of the electrostatic chuck 11 is Depending on the shape and the shape of the contact portion 12a, the tip of the flange portion 10b may be positioned above the outer peripheral edge portion 11a.

  Further, in the above embodiment, the locking portion 10a has a concave shape toward the center of the electrostatic chuck 11, but the shape of the locking portion 10a is such that the contact portion 12a is the same as the locking portion 10a. What is necessary is just to come to be covered with the collar part 10b in planar view in the latched state, and is not limited to this shape. As an example of another locking portion 10a, as shown in FIG. 4 for example, the lower surface of the focus ring 10 is recessed upward, and this recess is further extended toward the outside of the focus ring 10, The tip of the contact portion 12a of the pressing member 12 is folded back in the outward direction of the focus ring 10 and formed on a substantially U-shape so that the contact portion 12a and the latching portion 10a are latched using this folded portion. You may do it.

  As mentioned above, although preferred embodiment of this invention was described, this invention is not limited to this example. It is obvious for those skilled in the art that various changes or modifications can be conceived within the scope of the technical idea described in the claims. It is understood that it belongs to.

DESCRIPTION OF SYMBOLS 1 Plasma processing apparatus 2 Mounting base 10 Focus ring 11 Electrostatic chuck 12 Press member 13 Susceptor 15a Refrigerant flow path 30 1st high frequency power supply 40 2nd high frequency power supply 50 Support member 51 Cylindrical member 60 Arc member 61 Shielding member 70 Cover member 80 Heat transfer member W Wafer

Claims (6)

A processing apparatus for an object to be processed,
A processing vessel defining a processing space;
A mounting table disposed in the processing space,
The mounting table includes an electrostatic chuck for mounting the object to be processed and a focus ring provided on an outer peripheral portion of the electrostatic chuck,
An annular pressing member that presses the focus ring against the electrostatic chuck;
A fixing member for fixing the pressing member to the electrostatic chuck,
The focus ring is formed with a locking portion that is recessed toward the center of the focus ring over the entire circumference of the outer surface,
The pressing member is formed by combining a plurality of arc members in an annular shape, and includes a contact portion that is locked to the locking portion of the focus ring and presses the focus ring against the electrostatic chuck, and the contact portion. An installation portion that extends downward and is fixed to the electrostatic chuck by the fixing member;
An apparatus for processing an object to be processed is characterized in that a flange portion is formed on an upper surface of an outer peripheral end portion of the focus ring so that a contact portion of the pressing member does not enter a visual field in a plan view. The processing apparatus for an object to be processed according to claim 1, wherein the installation portion of the pressing member is covered with a covering member made of quartz. The covering member is provided in contact with the outer peripheral end of the flange portion of the focus ring,
A shielding member is provided between the covering member and the installation portion so as to cover the installation portion from entering the field of view from a boundary between the flange portion of the focus ring and the covering member in a plan view. The processing apparatus of the to-be-processed object of Claim 2 characterized by the above-mentioned. The processing apparatus for an object to be processed according to claim 1, wherein a heat transfer member is interposed between the electrostatic chuck and the focus ring. The processing apparatus for an object to be processed according to claim 1, wherein the pressing member is made of ceramics. A mounting table for a target object disposed in a plasma processing container, comprising: an electrostatic chuck for mounting a target object; and a focus ring provided on the outer periphery of the electrostatic chuck;
An annular pressing member that presses the focus ring against the electrostatic chuck;
A fixing member for fixing the pressing member to the electrostatic chuck,
The focus ring is formed with a locking portion that is recessed toward the center of the focus ring over the entire circumference of the outer surface,
The pressing member is formed by combining a plurality of arc members in an annular shape, and includes a contact portion that is locked to the locking portion of the focus ring and presses the focus ring against the electrostatic chuck, and the contact portion. An installation portion that extends downward and is fixed to the electrostatic chuck by the fixing member;
A mounting table for an object to be processed, wherein a flange portion is formed on an upper surface of an outer peripheral end portion of the focus ring so as to cover a contact portion of the pressing member so as not to enter a field of view in a plan view.

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