TWI772608B - Plasma processing apparatus - Google Patents

Abstract

A plasma processing apparatus includes an insertion member having a first surface facing a vacuum space, a second surface facing a non-vacuum space, and an insertion hole penetrating through the first and second surfaces. A pin is inserted into the insertion hole and moved vertically. A movable member is provided in a recess formed on a wall surface of the insertion hole facing the pin. The movable member has an opening into which the pin is inserted and is movable along a surface of the recess. A first sealing member is provided between the movable member and the pin. A second sealing member is provided between the movable body and the surface of the recess and allows, when a pressing force of the pin that locally compresses the first sealing member acts on the first sealing member, the movable member to move in a direction to release the pressing force.

Description

Plasma processing device

The present invention relates to a plasma processing device.

Conventionally, plasma processing apparatuses are known that use plasma to perform plasma processing on objects to be processed, such as wafers. Such a plasma processing apparatus has, for example, a mounting table for holding the object to be processed that also serves as an electrode in a processing container that can constitute a vacuum space. The plasma processing apparatus performs plasma processing on the object to be processed placed on the mounting table by applying a specific high-frequency power to the mounting table in the vacuum space formed in the processing container. An insertion hole penetrating the front surface and the back surface of the vacuum space side of the mounting table is formed on the mounting table, and a pin is inserted into the insertion hole. In a plasma processing apparatus, when a to-be-processed object is conveyed, a pin is made to protrude from an insertion hole, a to-be-processed object is supported by a pin from the back surface, and the to-be-processed object is detached from a mounting table.

A sealing member such as an O-ring is provided on the wall surface of the insertion hole facing the pin along the circumferential direction of the insertion hole. The sealing member seals the insertion hole by being in contact with the pin. In the plasma processing apparatus, the insertion hole is sealed by the sealing member, thereby maintaining the airtightness of the vacuum space in the processing container. [Prior Art Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. 2013-42012

[Problems to be Solved by Invention]

The present invention provides a technique for properly sealing an insertion hole into which a pin is inserted. [Technical means to solve problems]

In one embodiment, the disclosed plasma processing apparatus includes an insertion member having a first surface disposed on the side of the vacuum space and a second surface disposed on the side of the non-vacuum space, and formed so as to penetrate the first surface. and an insertion hole on the second surface; a pin, which is inserted into the insertion hole, and moves in the vertical direction; a movable member, into which the pin is inserted, and is formed in a recessed portion of the wall surface formed in the insertion hole opposite to the pin, along the a first sealing member disposed between the movable member and the pin; and a second sealing member disposed between the movable member and the concave portion The movable member is allowed to move in the direction in which the pressing force is released when the pressing force that locally compresses the first sealing member from the pin to the first sealing member acts between the above-mentioned surfaces. [Effect of invention]

According to one aspect of the disclosed plasma processing apparatus, the effect that the insertion hole into which the pin is inserted can be properly sealed can be obtained.

Hereinafter, embodiments of the disclosed plasma processing apparatus will be described in detail based on the drawings. In addition, the disclosure technique is not limited to this embodiment.

Conventionally, plasma processing apparatuses are known that use plasma to perform plasma processing on objects to be processed, such as wafers. Such a plasma processing apparatus has, for example, a mounting table for holding the object to be processed that also serves as an electrode in a processing container that can constitute a vacuum space. The plasma processing apparatus performs plasma processing on the object to be processed placed on the mounting table by applying a specific high-frequency power to the mounting table in the vacuum space formed in the processing container.

Here, the configuration of the essential parts of the mounting table 130 in the prior art will be described with reference to FIG. 8 . FIG. 8 is a schematic cross-sectional view showing a configuration of an essential part of the mounting table 130 in the prior art. As shown in FIG. 8 , the mounting table 130 is formed with insertion holes 170 penetrating the front and rear surfaces of the vacuum space side of the mounting table 130 , and the pins 172 are inserted into the insertion holes 170 . In the plasma processing apparatus, when the wafer as the object to be processed is transported, the pins 172 are made to protrude from the insertion holes 170 , and the pins 172 support the wafer from the back surface and separate the wafer from the mounting table 130 .

On the wall surface of the insertion hole 170 facing the pin 172 , a sealing member 286 such as an O-ring is provided along the circumferential direction of the insertion hole 170 . The sealing member 286 seals the insertion hole 170 by being in contact with the pin 172 . In the plasma processing apparatus, the insertion hole 170 is sealed by the sealing member 286, thereby maintaining the airtightness of the vacuum space in the processing container.

However, in the plasma processing apparatus, when the temperature of the mounting table is controlled according to various plasma processes, the mounting table expands or contracts according to the temperature change. When the axis of the insertion hole of the mount is displaced from the axis of the pin due to expansion or contraction of the mount, a pressing force that locally compresses the seal member is applied from the pin to the seal member provided in the insert hole. If the sealing member is locally compressed, a gap may be generated between the uncompressed portion of the sealing member and the pin, and as a result, there is a problem that it is difficult to sufficiently seal the insertion hole. For example, in the example shown in FIG. 8 , the mounting table 130 expands in the radial direction of the mounting table 130 according to the temperature change, thereby locally compressing the sealing member 286 , the uncompressed portion of the sealing member 286 and the pin 172 the possibility of a gap between them. Furthermore, this problem is not limited to the mounting table, but can also occur similarly to other parts in which insertion holes into which pins are inserted are formed. When the insertion hole is not properly sealed, there is a possibility that the airtightness of the vacuum space in the processing container will decrease.

(first embodiment) [Configuration of plasma processing apparatus] FIG. 1 is a diagram showing a schematic configuration of a plasma processing apparatus according to the first embodiment. In FIG. 1, the cross section of the plasma processing apparatus of 1st Embodiment is shown.

As shown in FIG. 1, the plasma processing apparatus 10 is a parallel plate type plasma processing apparatus. The plasma processing apparatus 10 is provided with the processing container 12 comprised airtightly. The processing container 12 has a substantially cylindrical shape, and a processing space S in which plasma is generated is defined as an inner space thereof. The plasma processing apparatus 10 includes a mounting table 13 in the processing container 12 . The upper surface of the mounting table 13 is formed as a mounting surface 54d on which a semiconductor wafer (hereinafter referred to as a "wafer") W that is an object to be processed is mounted. In this embodiment, the mounting table 13 has the base 14 and the electrostatic chuck 50 . The base 14 has a substantially disc shape, and is provided below the processing space S. As shown in FIG. The base 14 is made of, for example, aluminum, and functions as a lower electrode.

The electrostatic chuck 50 is disposed on the upper surface of the base 14 . The upper surface of the electrostatic chuck 50 is in the shape of a flat disk, and the upper surface corresponds to the placement surface 54d on which the wafer W is placed. The electrostatic chuck 50 has electrodes 54a and an insulator 54b. The electrode 54a is provided inside the insulator 54b, and the DC power supply 56 is connected to the electrode 54a via the switch SW. A DC voltage is applied to the electrode 54 a from the DC power supply 56 to generate a Coulomb force, and the wafer W is attracted and held on the electrostatic chuck 50 by the Coulomb force. Moreover, the electrostatic chuck 50 has the heater 54c inside the insulator 54b. The heater 54c heats the electrostatic chuck 50 by supplying power from a power feeding mechanism (not shown). Thereby, the temperature of the mounting table 13 and the wafer W is controlled.

In the present embodiment, the plasma processing apparatus 10 further includes a cylindrical holding portion 16 and a cylindrical support portion 17 . The cylindrical holding portion 16 is in contact with the edges of the side surface and the bottom surface of the base 14 to hold the base 14 . The cylindrical support portion 17 extends in the vertical direction from the bottom of the processing container 12 , and supports the base 14 via the cylindrical holding portion 16 .

A focus ring 18 is provided on the upper surface of the peripheral portion of the base 14 . The focus ring 18 is a member for improving the in-plane uniformity of the processing accuracy of the wafer W. FIG. The focus ring 18 is a generally annular plate-like member comprising, for example, silicon, quartz, or silicon carbide.

In the present embodiment, the exhaust passage 20 is formed between the side wall of the processing container 12 and the cylindrical support portion 17 . A partition 22 is installed at the entrance of the exhaust passage 20 or in the middle thereof. In addition, an exhaust port 24 is provided at the bottom of the exhaust passage 20 . The exhaust port 24 is defined by an exhaust pipe 28 embedded in the bottom of the processing container 12 . An exhaust device 26 is connected to the exhaust pipe 28 . The exhaust device 26 has a vacuum pump, and by operating the vacuum pump, the processing space S in the processing container 12 can be decompressed to a predetermined degree of vacuum. Thereby, the processing space S in the processing container 12 is kept in a vacuum environment. The processing space S is an example of a vacuum space. On the side wall of the processing container 12 , a gate valve 30 for opening and closing the inlet and outlet of the wafer W is installed.

A high-frequency power supply 32 is electrically connected to the base 14 via a matching device 34 . The high-frequency power source 32 is a power source for plasma generation, and applies a high-frequency power of a specific high frequency (eg, 13 MHz) to the lower electrode, that is, the base 14 . In addition, a refrigerant flow path (not shown) is formed in the base 14 , and the plasma processing apparatus 10 cools the mounting table 13 by circulating the refrigerant through the refrigerant flow path. Thereby, the temperature of the mounting table 13 and the wafer W is controlled.

The mounting table 13 is provided with a plurality of, for example, three pin insertion holes 70 (only two pin insertion holes 70 are shown in FIG. 1 ), and pins 72 are inserted into these pin insertion holes 70 . The pin 72 is connected to the driving mechanism 74 and is driven in the up-down direction by the driving mechanism 74 . The configuration of the mounting table 13 including the pin insertion holes 70 and the pins 72 will be described later.

The plasma processing apparatus 10 further includes a shower head 38 in the processing container 12 . The shower head 38 is arranged above the processing space S. The shower head 38 includes an electrode plate 40 and an electrode holder 42 .

The electrode plate 40 is a conductive plate having a substantially disc shape, and constitutes an upper electrode. The high-frequency power supply 35 is electrically connected to the electrode plate 40 via the matching device 36 . The high-frequency power source 35 is a power source for plasma generation, and applies a high-frequency power of a specific high frequency (eg, 60 MHz) to the electrode plate 40 . When high-frequency power is applied to the base 14 and the electrode plate 40 by the high-frequency power supply 32 and the high-frequency power supply 35, respectively, a high-frequency electric field is formed in the space between the base 14 and the electrode plate 40, that is, in the processing space S, and generate plasma.

A plurality of gas vent holes 40h are formed in the electrode plate 40 . The electrode plate 40 is detachably supported by the electrode holder 42 . A buffer chamber 42 a is provided inside the electrode holder 42 . The plasma processing apparatus 10 further includes a gas supply unit 44 , and the gas supply unit 44 is connected to the gas inlet 25 of the buffer chamber 42 a via a gas supply conduit 46 . The gas supply unit 44 supplies the processing gas to the processing space S. The process gas may be, for example, a process gas for etching, or a process gas for film formation. The electrode holder 42 is formed with a plurality of holes continuous with the plurality of gas vent holes 40h, respectively, and the plurality of holes communicate with the buffer chamber 42a. The gas supplied from the gas supply unit 44 is supplied to the processing space S through the buffer chamber 42a and the gas vent hole 40h.

In this embodiment, the top wall of the processing container 12 is provided with a magnetic field forming mechanism 48 extending annularly or concentrically. The magnetic field forming mechanism 48 functions so that the high-frequency discharge in the processing space S is easily started (plasma ignition) and the discharge is stably maintained.

In the present embodiment, the plasma processing apparatus 10 further includes a gas supply line 58 and a heat transfer gas supply unit 62 . The heat transfer gas supply part 62 is connected to the gas supply line 58 . The gas supply line 58 extends to the upper surface of the electrostatic chuck 50 and extends in a ring shape on the upper surface. The heat transfer gas supply unit 62 supplies heat transfer gas such as He gas between the upper surface of the electrostatic chuck 50 and the wafer W.

The plasma processing apparatus 10 having the above-described configuration is collectively controlled by the control unit 90 for its operation. The control unit 90 is provided with a process controller 91 , a user interface 92 , and a memory unit 93 that includes a CPU (Central Processing Unit) and controls each unit of the plasma processing apparatus 10 .

The user interface 92 includes a keyboard for a project manager to input commands for managing the plasma processing apparatus 10 , a display for visually displaying the operating status of the plasma processing apparatus 10 , and the like.

The memory unit 93 stores a recipe, and the recipe stores a control program (software) or processing condition data for realizing various processes performed by the plasma processing apparatus 10 under the control of the process controller 91 . Furthermore, according to the need, any recipe can be called from the memory unit 93 by an instruction from the user interface 92 or the like and the process controller 91 can execute it, so as to perform the required operation in the plasma processing apparatus 10 under the control of the process controller 91 . deal with. In addition, recipes such as control programs or processing condition data can also be stored in a computer-readable storage medium (eg, hard disk, CD (Compact Disc), floppy disk, semiconductor memory, etc.) . In addition, recipes such as control programs or processing condition data can also be transmitted at any time from other devices via, for example, dedicated lines, and used online.

[Configuration of the stage 13] Next, with reference to FIG. 2, the main part structure of the mounting table 13 of 1st Embodiment is demonstrated. FIG. 2 is a schematic cross-sectional view showing the configuration of a main part of the mounting table 13 according to the first embodiment. The mounting table 13 includes the base 14 and the electrostatic chuck 50 as described above, and is configured so that the pins 72 can be inserted from below the base 14 to the upper side of the electrostatic chuck 50 . The mounting table 13 is an example of an insertion member.

The electrostatic chuck 50 is formed in a disk shape, and is supported by the base 14 . The upper surface of the electrostatic chuck 50 forms a mounting surface 54d on which the wafer W is mounted. The upper surface of the base 14 is engaged with the lower surface of the electrostatic chuck 50 . On the lower surface of the base 14, a back surface 14a opposite to the placement surface 54d is formed.

A pin insertion hole 70 into which the pin 72 is inserted is formed in the mounting surface 54d. The pin insertion hole 70 penetrates the mounting surface 54d and the back surface 14a facing the mounting surface 54d. The pin insertion hole 70 is formed by the first through hole 76 and the second through hole 78 . The first through holes 76 are formed in the electrostatic chuck 50 , and the second through holes 78 are formed in the base 14 . A concave portion 82 is formed in the wall surface of the pin insertion hole 70 facing the pin 72 .

The pin 72 is connected to the drive mechanism 74 shown in FIG. 1 , and is driven by the drive mechanism 74 to move up and down in the pin insertion hole 70 , and to move freely from the mounting surface 54d of the mounting table 13 . That is, in the state where the pins 72 are raised, the front ends of the pins 72 protrude from the mounting surface 54d of the mounting table 13, and support the wafer W. On the other hand, in the state in which the pins 72 are lowered, the front ends of the pins 72 are accommodated in the pin insertion holes 70, and the wafer W is placed on the placement surface 54d.

A movable member 84 is provided in the concave portion 82 of the pin insertion hole 70 . The movable member 84 has an opening into which the pin 72 is inserted, and is provided in the recess 82 so as to be movable along an upper surface 82 a of the recess 82 that intersects with the axial direction of the pin 72 .

The first sealing member 86 is arranged between the movable member 84 and the pin 72 . In the pin insertion hole 70 , the gap formed by the movable member 84 and the pin 72 moving in the vertical direction in the pin insertion hole 70 is sealed by the first sealing member 86 . The first sealing member 86 is, for example, OmniSeal (registered trademark) or an O-ring.

A second sealing member 88 is arranged between the movable member 84 and the upper surface 82a of the recessed portion 82 . In the pin insertion hole 70 , the gap formed by the movable member 84 and the upper surface 82 a of the recessed portion 82 is sealed by the second sealing member 88 . The second sealing member 88 is, for example, OmniSeal (registered trademark) or an O-ring.

The upper surface of the mounting table 13 is formed as a mounting surface 54d on which the wafer W is mounted, and the lower surface of the mounting table 13 is formed as a back surface 14a opposed to the mounting surface 54d. The mounting surface 54d of the mounting table 13 is arrange|positioned at the processing space S side of the vacuum space maintained as a vacuum environment. On the other hand, the back surface 14a of the mounting table 13 is arrange|positioned at the non-vacuum space side which maintains an atmospheric environment. The non-vacuum space is, for example, the space R surrounded by the inner side surface of the cylindrical holding portion 16 . The processing space S and the space R communicate with each other through the pin insertion holes 70 . The plasma processing apparatus 10 seals the pin insertion hole 70 by the first sealing member 86 and the second sealing member 88, thereby suppressing the inflow of the atmosphere on the side of the space R into the processing space S (ie, the vacuum space in the processing container 12).

In addition, in the plasma processing apparatus 10, when the temperature of the mounting table 13 is controlled according to various plasma processes, the mounting table 13 expands or contracts according to the temperature change. Due to the expansion or contraction of the mounting table 13, the axis of the pin insertion hole 70 of the mounting table 13 is displaced from the axis of the pin 72, so that the pin 72 acts on the first sealing member 86 to partially compress the first sealing member 86. pressure. When the first sealing member 86 is partially compressed, a gap may be generated between the uncompressed portion of the first sealing member 86 and the pin 72 , and as a result, it is difficult to sufficiently seal the pin insertion hole 70 .

FIG. 3 is a diagram for explaining the offset between the axis of the pin insertion hole 70 and the axis of the pin 72 of the mounting table 13 . The mounting table 13 has the mounting surface 54d and the back surface 14a which opposes the mounting surface 54d. Moreover, the insertion hole 70 for pins which penetrates the mounting surface 54d and the back surface 14a which opposes the mounting surface 54d is formed in the mounting base 13. The temperature of the mounting table 13 is controlled by the heater 54c of the electrostatic chuck 50 and the refrigerant flow path (not shown) of the base 14 . In the plasma processing apparatus 10, when the temperature of the mounting table 13 is controlled, the mounting table 13 expands or contracts according to the temperature change. In this embodiment, it is assumed that the mounting table 13 expands according to the temperature change. For example, in the plasma processing apparatus 10, the mounting table 13 expands in the radial direction of the mounting table 13 according to the temperature change. In FIG. 3 , the expansion direction of the mounting table 13 is indicated by a white arrow. Since the mounting table 13 expands in the radial direction of the mounting table 13 , the shaft 70 a of the pin insertion hole 70 of the mounting table 13 is displaced in the radial direction of the mounting table 13 with respect to the axis 72 a of the pin 72 . Therefore, the first sealing member 86 is pressed against the pin 72 by the mounting table 13 , the second sealing member 88 and the movable member 84 . Thereby, as a reaction force of the force pressing the first sealing member 86 against the pin 72 , a pressing force that locally compresses the first sealing member 86 acts on the first sealing member 86 from the pin 72 . In FIG. 3 , the pressing force that locally compresses the first sealing member 86 acts in the opposite direction to the expansion direction of the mounting table 13 (ie, the direction indicated by the white arrow), and the pin 72 locally compresses the first sealing member 86 . The right side portion of the sealing member 86 . When the right side portion of the first seal member 86 is partially compressed, a gap is created between the uncompressed left side portion of the first seal member 86 and the pin 72, and the atmosphere may flow in through the gap.

Therefore, in the plasma processing apparatus 10, when a pressing force that locally compresses the first sealing member 86 acts on the first sealing member 86 from the pin 72, the second sealing member 88 is allowed to release the pressing force in a direction that allows the second sealing member 88 to release the pressing force. Movement of the movable member 84 . For example, as shown in FIG. 3 , it is assumed that the pressing force for locally compressing the first sealing member 86 acts in the opposite direction to the expansion direction of the mounting table 13 (ie, the direction indicated by the white arrow). In this case, the second sealing member 88 slides along the upper surface 82a of the recessed portion 82 in a direction opposite to the expansion direction of the mounting table 13, thereby allowing the movable member 84 to move.

Thereby, since the pressing force which locally compresses the 1st sealing member 86 is released, the generation|occurence|production of a clearance gap between the uncompressed left side part of the 1st sealing member 86 and the pin 72 can be prevented. As a result, the plasma processing apparatus 10 can be properly sealed by the first sealing member 86 and the second sealing member 88 even when the axis of the pin insertion hole 70 of the mounting table 13 and the axis of the pin 72 are displaced. The pin insertion hole 70 is used.

As described above, the plasma processing apparatus 10 according to the first embodiment includes the mounting table 13 , the pins 72 , the movable member 84 , the first sealing member 86 , and the second sealing member 88 . The mounting table 13 has a mounting surface 54d arranged on the vacuum space side and a back surface 14a arranged on the non-vacuum space side, and has pin insertion holes 70 penetrating the mounting surface 54d and the back surface 14a. The pin 72 is inserted into the pin insertion hole 70 and moves in the up-down direction. The movable member 84 is inserted into the pin 72, and is movably provided along the upper surface 82a of the recess 82 intersecting the axial direction of the pin 72 in the recess 82 formed in the wall surface of the pin insertion hole 70 facing the pin 72. The first sealing member 86 is arranged between the movable member 84 and the pin 72 . The second sealing member 88 is disposed between the movable member 84 and the upper surface 82a of the recess 82, and when a pressing force that locally compresses the first sealing member 86 acts on the first sealing member 86 from the pin 72, the second sealing member 88 is released to the The direction of the pressing force allows movement of the movable member 84 . Thereby, even when the axis of the pin insertion hole 70 of the mounting table 13 and the axis of the pin 72 are displaced due to the expansion or contraction of the mounting table 13, the plasma processing apparatus 10 can use the first sealing member. 86 and the second sealing member 88 properly seal the pin insertion hole 70 .

Hereinafter, the evaluation experiment performed for verifying the effect of the plasma processing apparatus 10 of 1st Embodiment is demonstrated.

[Evaluation device] First, the evaluation apparatus 500 used in the evaluation experiment will be described. FIG. 6 is a diagram illustrating a configuration example of the evaluation apparatus 500 . The evaluation apparatus 500 shown in FIG. 6 has the container 121 for experiments. The experimental container 121 is formed in a substantially cylindrical shape and has an opening at the bottom. The sample 510 is attached to the opening of the experimental container 121 . By installing the sample 510 through the opening of the experimental container 121 , a space Q is formed inside the experimental container 121 .

The sample 510 has the bottom plate 141 , the pin 72 , the movable member 84 , the first sealing member 86 , and the second sealing member 88 . The bottom plate 141 , the pin 72 , the movable member 84 , the first sealing member 86 and the second sealing member 88 are respectively the same as the mounting table 13 , the pin 72 , the movable member 84 , the first sealing member 86 and the second sealing member 88 shown in FIG. 2 . correspond.

Moreover, the exhaust port 121a is formed in the side wall of the container 121 for experiments, and the vacuum pump 123 is connected to the exhaust port 121a via the exhaust pipe 122. An on-off valve 122 a is provided in the exhaust pipe 122 . The vacuum pump 123 is constituted so as to be able to depressurize the inside of the experiment container 121 to a predetermined degree of vacuum. The degree of vacuum (pressure) of the experimental container 121 is measured by the pressure gauge 121b.

[Evaluation experiment] In the evaluation experiment, the sample 510 was installed in the evaluation device 500, and by sequentially performing steps (1) to (6) shown below, the amount of air flowing into the space Q from the pin insertion hole 70 of the bottom plate 141 was measured ( Hereinafter referred to as "leakage"). The sample 510 corresponds to the plasma processing apparatus 10 of the first embodiment.

Step (1): With the vacuum pump 123, the vacuum degree of the experimental container 121 is reduced to about 2.5 Pa. Step (2): Offset the shaft 72a of the pin 72 in the radial direction of the base plate 141 relative to the shaft 70a of the pin insertion hole 70 of the base plate 141 . Step (3): Close the on-off valve 122a. Step (4): With the driving mechanism 74, the pin 72 is made to reciprocate 100 times in the range of 5 mm in the up-down direction in 10 minutes. Step (5): After performing step (4) for 10 minutes, measure the vacuum degree (pressure) of the experimental container 121 by the pressure gauge 121b. Step (6): Multiply the increase in the vacuum degree (pressure) of the experimental container 121 during the 10 minutes (=600 seconds) of step (4) by the volume of the experimental container 121 to calculate the leakage (Pa·m). ³ /sec).

[Comparative experiment] Moreover, in the comparative experiment, the comparative sample was attached to the evaluation apparatus 500, and the amount of leakage was measured by performing the above-mentioned steps (1) to (6) in sequence. The comparative sample corresponds to a plasma processing apparatus having a stage 130 (see FIG. 8 ) in the prior art, and instead of the movable member 84 , the first sealing member 86 and the second sealing member 88 , there is a single seal around the pin 72 The point of member 286 is different from that of sample 510 .

FIG. 7 is a diagram showing an example of the relationship between the amount of displacement of the shaft 72a of the pin 72 and the amount of leakage. FIG. 7 shows the result of measuring the leakage amount by changing the offset of the shaft 72a of the pin 72. As shown in FIG. In Fig. 7, "Comparative Example" is the leakage amount corresponding to the comparative experiment, and "Example" is the leakage amount corresponding to the evaluation experiment.

As shown in FIG. 7, in the comparative experiment, when the offset of the shaft 72a of the pin 72 is 0.1 mm, the leakage amount exceeds the range of the predetermined allowable specification. On the other hand, in the evaluation experiment, even when the offset amount of the shaft 72a of the pin 72 was 0.9 mm, the leakage amount fell within the range of the predetermined allowable specification. That is, even when the shaft 70a of the pin insertion hole 70 of the mounting table 13 and the shaft 72a of the pin 72 are displaced, it can be confirmed that the first sealing member 86 and the second sealing member 88 can properly seal the pin Insert hole 70.

(Second Embodiment) Next, the second embodiment will be described. The plasma processing apparatus 10 of the second embodiment has the same configuration as that of the plasma processing apparatus 10 of the first embodiment described above, except for the configuration of the mounting table 13 . Therefore, in the second embodiment, the same reference numerals are used for the same components as those in the above-described first embodiment, and detailed descriptions thereof are omitted.

[Configuration of the stage 13] 4 and 5, the main part configuration of the mounting table 13 according to the second embodiment will be described. FIG. 4 is a perspective view showing the configuration of a main part of the mounting table 13 according to the second embodiment. As shown in FIG. 4 , the mounting table 13 includes a first mounting table 102 and a second mounting table 107 provided on the outer periphery of the first mounting table 102 . The first mounting table 102 and the second mounting table 107 are arranged so as to be coaxial with each other.

The first mounting table 102 includes a base 103 . The base 103 is formed in a columnar shape, and the electrostatic chuck 50 described above is disposed on one surface 103a in the axial direction. Moreover, the base 103 is provided with the flange part 200 which protrudes outward along the outer periphery. The base 103 of the present embodiment is formed with a protruding portion 201 extending outward by increasing the outer diameter from the center portion of the side surface of the outer periphery to the lower side. the flange portion 200. The flange portion 200 is formed with through holes 210 penetrating in the axial direction at three or more positions in the circumferential direction of the upper surface. In the flange portion 200 of the present embodiment, three through holes 210 are formed at equal intervals in the circumferential direction. The through hole 210 functions as a pin insertion hole into which a pin 220 described later is inserted. The first stage 102 is an example of an insertion member.

The second stage 107 includes a base 108 . The base 108 is formed in a cylindrical shape whose inner diameter is larger than the outer diameter of the surface 103a of the base 103 by a certain size, and the above-mentioned focus ring 18 is disposed on one surface 108a in the axial direction. In addition, pins 220 are provided on the lower surface of the base 108 at the same distance as the through holes 210 of the flange portion 200 . In the base 108 of the present embodiment, three pins 220 are fixed on the lower surface at equal intervals in the circumferential direction. The base 108 is an example of a common member.

The base 108 is coaxial with the base 103 , and is disposed on the flange portion 200 of the base 103 by aligning the positions in the circumferential direction so that the pins 220 are inserted into the through holes 210 .

FIG. 5 is a schematic cross-sectional view showing the configuration of the main parts of the first mounting table 102 and the second mounting table 107 according to the second embodiment. The example of FIG. 5 is a figure which shows the cross section of the 1st stage 102 and the 2nd stage 107 in the position of the through-hole 210. As shown in FIG.

The base 103 is supported by a support base 104 of an insulator. Through holes 210 are formed in the base 103 and the support 104 .

The through-hole 210 is formed with a step 211 having a smaller diameter from the vicinity of the center to the lower portion than the upper portion. The pin 220 corresponds to the through hole 210, and the diameter is formed to be smaller from the vicinity of the center to the lower part than the upper part.

The base 108 is disposed on the flange portion 200 of the base 103 . The base 108 is formed with a larger outer diameter than the base 103 , and a ring portion 221 protruding downward is formed on a portion of the lower surface facing the base 103 larger than the base 103 in outer diameter. When the base 108 is arranged on the flange portion 200 of the base 103 , the annular portion 221 is formed so as to cover the side surface of the flange portion 200 .

The pin 220 is inserted into the through hole 210 . An elevating mechanism 120 for elevating and lowering the second stage 107 is provided in each of the through holes 210 . For example, the base 103 is provided with an elevating mechanism 120 for raising and lowering the pins 220 in the lower portion of each through hole 210 . The lift mechanism 120 has a built-in actuator, and the rod 120a is extended and retracted by the driving force of the actuator, so that the pin 220 is raised and lowered. The pin 220 moves in the vertical direction in the through hole 210 by the lifting and lowering by the lifting mechanism 120 .

A concave portion 182 is formed on the wall surface of the through hole 210 facing the pin 220 . A movable member 184 is provided in the recessed portion 182 . The movable member 184 has an opening into which the pin 220 is inserted, and is movably provided in the recess 182 along the upper surface 182 a of the recess 182 that intersects the axial direction of the pin 220 .

The first sealing member 186 is arranged between the movable member 184 and the pin 220 . In the through hole 210 , the gap formed by the movable member 184 and the pin 220 moving in the vertical direction in the through hole 210 is sealed by the first sealing member 186 . The first sealing member 186 is, for example, OmniSeal (registered trademark) or an O-ring.

A second sealing member 188 is arranged between the movable member 184 and the upper surface 182 a of the recessed portion 182 . In the through hole 210 , the gap formed by the movable member 184 and the upper surface 182 a of the recess 182 is sealed by the second sealing member 188 . The second sealing member 188 is, for example, OmniSeal (registered trademark) or an O-ring.

The first stage 102 keeps the lower space in the atmospheric environment. For example, a space 270 is formed in the lower part of the inner side of the support table 104, and the space 270 is kept in an atmospheric environment. The upper surface of the 1st stage 102 (for example, the upper surface of the flange part 200 of the base 103) is arrange|positioned at the processing space S side of the vacuum space maintained as a vacuum environment. On the other hand, the lower surface of the first mounting table 102 (for example, the lower surface of the support table 104 ) is disposed on the side of the space 270 , which is a non-vacuum space maintained in an atmospheric environment. The processing space S communicates with the space 270 through the through hole 210 . In the plasma processing apparatus 10 , the through hole 210 is sealed by the first sealing member 186 and the second sealing member 188 , thereby suppressing the inflow of the atmosphere on the space 270 side into the processing space S (ie, the vacuum space in the processing container 12 ).

In addition, in the plasma processing apparatus 10, when the three pins 220 are fixed to the lower surface of the base 108 by machining, there is an axis of any pin 220 among the three pins 220 relative to the axis for the arbitrary pin 220. The case where the axis of the inserted through hole 210 is offset. When the axis of the arbitrary pin 220 is displaced relative to the axis of the through hole 210 into which the arbitrary pin 220 is inserted, a pressing force that locally compresses the first sealing member 186 acts from the arbitrary pin 220 to the first sealing member 186 . When the first sealing member 186 is partially compressed, a gap may be generated between the uncompressed portion of the first sealing member 186 and any pin 220 , and as a result, it is difficult to sufficiently seal the through hole 210 .

Therefore, in the plasma processing apparatus 10, when a pressing force that locally compresses the first sealing member 186 acts on the first sealing member 186 from the pin 220, the second sealing member 188 allows the second sealing member 188 to release the pressing force. Movement of the movable member 184 . For example, it is assumed that the pressing force that locally compresses the first sealing member 186 acts in the same direction as the direction in which the axis of any pin 220 is displaced. In this case, the second sealing member 188 slides along the upper surface 182a of the recessed portion 182 in the same direction as the offset direction of the axis of any pin 220, thereby allowing the movable member 184 to move.

Thereby, since the pressing force which locally compresses the first sealing member 186 is released, it is possible to prevent a gap from being generated between the uncompressed portion of the first sealing member 186 and the pin 220 . As a result, the plasma processing apparatus 10 can be properly sealed by the first sealing member 186 and the second sealing member 188 even when the axis of the through hole 210 of the first stage 102 and the axis of the pin 220 are displaced Through hole 210 .

10‧‧‧Plasma processing device 12‧‧‧Disposal container 13‧‧‧Place 14‧‧‧Abutment 14a‧‧‧Back 16‧‧‧cylindrical support 17‧‧‧cylindrical support 18‧‧‧Focus ring 20‧‧‧Exhaust passage 22‧‧‧Partition 24‧‧‧Exhaust port 25‧‧‧Gas inlet 26‧‧‧Exhaust 28‧‧‧Exhaust pipe 30‧‧‧Gate valve 32‧‧‧High Frequency Power Supply 34‧‧‧matcher 35‧‧‧High Frequency Power Supply 36‧‧‧matcher 38‧‧‧Shower head 40‧‧‧Electrode plate 40a‧‧‧Buffer room 40h‧‧‧Gas vent 42‧‧‧Electrode support 42a‧‧‧Buffer room 44‧‧‧Gas Supply Section 46‧‧‧Gas supply conduit 48‧‧‧Magnetic field forming mechanism 50‧‧‧Electrostatic chuck 54a‧‧‧electrode 54b‧‧‧Insulator 54c‧‧‧heater 54d‧‧‧ mounting surface 56‧‧‧DC power supply 58‧‧‧Gas supply lines 62‧‧‧Heat-conducting gas supply part 70‧‧‧Pin insertion hole 70a‧‧‧shaft 72‧‧‧pin 72a‧‧‧shaft 74‧‧‧Drive mechanism 76‧‧‧First through hole 78‧‧‧Second through hole 82‧‧‧Recess 82a‧‧‧Top surface 84‧‧‧Moveable components 86‧‧‧First sealing member 88‧‧‧Second sealing member 90‧‧‧Control Department 91‧‧‧Process Controller 92‧‧‧User Interface 93‧‧‧Memory Department 102‧‧‧First stage 103‧‧‧Abutment 103a‧‧‧Surface 104‧‧‧Support Desk 107‧‧‧Second stage 108‧‧‧Abutment 108a‧‧‧Surface 120‧‧‧Lifting mechanism 120a‧‧‧pole 121‧‧‧Experimental container 121a‧‧‧Exhaust port 121b‧‧‧Pressure Gauge 122‧‧‧Exhaust pipe 122a‧‧‧On-off valve 123‧‧‧Vacuum Pump 130‧‧‧Place 141‧‧‧Bottom plate 170‧‧‧Insertion hole 172‧‧‧pins 182‧‧‧Recess 182a‧‧‧Top surface 184‧‧‧Moveable components 186‧‧‧First sealing member 188‧‧‧Second sealing member 200‧‧‧Flange 201‧‧‧Extension 210‧‧‧Through hole Step 211‧‧‧ 220‧‧‧pin 221‧‧‧Circle 270‧‧‧Space 286‧‧‧Sealing components 500‧‧‧Evaluation Device 510‧‧‧Sample Q‧‧‧Space R‧‧‧Space S‧‧‧processing space SW‧‧‧Switch W‧‧‧Wafer

FIG. 1 is a diagram showing a schematic configuration of a plasma processing apparatus according to a first embodiment. FIG. 2 is a schematic cross-sectional view showing the configuration of a main part of a mounting table according to the first embodiment. FIG. 3 is a view for explaining the offset between the shaft of the pin insertion hole and the shaft of the pin of the mounting table. Fig. 4 is a perspective view showing the configuration of a main part of a mounting table according to the second embodiment. FIG. 5 is a schematic cross-sectional view showing the configuration of the main parts of the first mounting table and the second mounting table according to the second embodiment. FIG. 6 is a diagram showing a configuration example of an evaluation apparatus. FIG. 7 is a diagram showing an example of the relationship between the amount of displacement of the shaft of the pin and the amount of leakage. FIG. 8 is a schematic cross-sectional view showing the configuration of an essential part of a mounting table in the prior art.

14‧‧‧Abutment

14a‧‧‧Back

50‧‧‧Electrostatic chuck

54a‧‧‧electrode

54d‧‧‧ mounting surface

70‧‧‧Pin insertion hole

70a‧‧‧shaft

72‧‧‧pin

72a‧‧‧shaft

82‧‧‧Recess

82a‧‧‧Top surface

84‧‧‧Moveable components

86‧‧‧First sealing member

88‧‧‧Second sealing member

Claims (4)

A plasma processing apparatus comprising: an insertion member having a first surface disposed on a vacuum space side and a second surface disposed on a non-vacuum space side, and formed to penetrate the first surface and the second surface an insertion hole; a pin inserted into the insertion hole and moved in the up-down direction; a movable member into which the pin is inserted and formed in a recessed portion of the wall surface of the insertion hole facing the pin along the recessed portion The surface intersecting the axial direction of the pin is movably provided; a first sealing member is arranged between the movable member and the pin; and a second sealing member is arranged between the movable member and the surface of the recessed portion In the meantime, when the pressing force that locally compresses the first sealing member acts on the first sealing member from the pin, the movable member is allowed to move in the direction in which the pressing force is released. The plasma processing apparatus of claim 1, wherein the insertion member expands or contracts according to a temperature change, and a pressing force that locally compresses the first sealing member acts in a direction opposite to the direction of expansion or contraction of the insertion member, The second sealing member is slid along the surface of the recessed portion in a direction opposite to the direction of expansion or contraction of the insertion member, thereby allowing movement of the movable member. The plasma processing apparatus according to claim 1, wherein a plurality of the insertion holes are formed in the insertion member, A plurality of the pins are provided, the plurality of pins are fixed to a common member, and an axis of an arbitrary pin among the plurality of pins is offset with respect to an axis of the insertion hole into which the arbitrary pin is inserted, thereby locally compressing the first sealing member The pressing force acts in the same direction as the offset direction of the axis of the arbitrary pin, and the second sealing member slides along the surface of the recessed portion in the same direction as the offset direction of the axis of the arbitrary pin, thereby , allowing the movement of the above-mentioned movable member. The plasma processing apparatus according to any one of claims 1 to 3, wherein the first sealing member and the second sealing member are O-rings.

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