JP2024017374A - plasma processing equipment - Google Patents

Abstract

The present invention provides a plasma processing apparatus in which the height of an antenna can be easily adjusted. A plasma processing apparatus (1) includes an outer cover (20) attached to a housing so as to close a first opening (12) provided in the housing (10), and a processing chamber (11). ) and the outer cover, an antenna (40) for generating plasma in the processing chamber, an insertion member (45) connected to the antenna, and the outer cover attached. and a position adjustment mechanism (60) for displacing the insertion member. [Selection diagram] Figure 1

Description

The present invention relates to a plasma processing apparatus that processes a base material using plasma.

2. Description of the Related Art Plasma processing apparatuses are known that generate inductively coupled plasma in a vacuum container using an antenna placed inside the vacuum container. The plasma processing apparatus performs predetermined plasma processing on a substrate to be processed using generated plasma depending on the type of the apparatus.

For example, Patent Document 1 includes a cathode on which a target can be installed, a plurality of high-frequency antennas arranged near the target, and a high-frequency power source that supplies high-frequency power to the high-frequency antenna to generate inductively coupled plasma. A film deposition apparatus is disclosed.

Japanese Patent Application Publication No. 2019-127621

However, in a plasma processing apparatus equipped with a plurality of high-frequency antennas, plasma processing on a substrate to be processed may become non-uniform due to various factors (individual differences in high-frequency antennas, variations in mounting positions, etc.). In order to uniformize plasma processing on a substrate to be processed, for example, it is necessary to individually adjust the heights of a plurality of high frequency antennas. The film forming apparatus described in Patent Document 1 has a problem in that in order to adjust the height of the high frequency antenna, it is necessary to open the processing chamber to the atmosphere, which takes time and effort.

One aspect of the present invention aims to realize a plasma processing apparatus in which the height of an antenna can be easily adjusted.

In order to solve the above problems, a plasma processing apparatus according to one aspect of the present invention is a plasma processing apparatus including a processing chamber, and includes a first opening that communicates the processing chamber with an external environment. an outer cover that is airtightly attached to the housing via a vacuum seal member so as to close the first opening and has a through hole; an inner cover supported so as to spatially divide the processing chamber and the outer cover inside the opening; and an enclosed space formed by being surrounded by at least the outer cover and the inner cover. an antenna disposed in the processing chamber for generating inductively coupled plasma in the processing chamber; an insertion member inserted into the through hole and connected to the antenna; a holding part that holds the insertion member so that the insertion member can be displaced while being sealed; and a position adjustment that adjusts the position of the antenna by displacing the insertion member with the outer cover attached. A mechanism.

According to the plasma processing apparatus according to one aspect of the present invention, the height of the antenna can be easily adjusted.

1 is a cross-sectional view schematically showing the configuration of a plasma processing apparatus according to a first embodiment. FIG. 2 is an enlarged view of region II in FIG. 1. FIG. 2 is an end view taken along the line III-III in FIG. 1. FIG. 1 is a cross-sectional view schematically showing an example of the configuration of a position adjustment mechanism according to Embodiment 1. FIG. 5 is a sectional view taken along the line VV in FIG. 4. FIG. FIG. 3 is a cross-sectional view schematically showing an example of the configuration of a position adjustment mechanism according to a second embodiment. 7 is a sectional view taken along the line VII-VII in FIG. 6. FIG. FIG. 3 is a diagram showing a first example in which a plurality of antennas are electrically connected to each other. FIG. 7 is a diagram showing a second example in which a plurality of antennas are electrically connected to each other. FIG. 7 is a diagram showing a third example in which a plurality of antennas are electrically connected to each other. FIG. 3 is a diagram for explaining an example of test results using the plasma processing apparatus according to the first embodiment.

[Embodiment 1]
Hereinafter, one embodiment of the present invention will be described in detail. It should be noted that the following description is provided for better understanding of the gist of the invention, and is not intended to limit the invention unless otherwise specified. In addition, the shapes and dimensions (length, width, etc.) of the structures described in each drawing in this application do not necessarily reflect the actual shapes and dimensions, and may be changed as appropriate for clarity and simplification of the drawings. are doing.

In this embodiment, as the predetermined plasma treatment, a predetermined film is formed on the surface of the substrate S as the object to be treated by a plasma CVD (Chemical Vapor Deposition) method using inductively coupled plasma. Although the plasma processing apparatus 1 that performs a film forming process for forming a film will be described as an example, the present invention is not limited thereto. For example, the present invention can be applied to a plasma processing apparatus 1 that performs a film forming process of forming a predetermined film on a base material S using a sputtering method. In a plasma processing apparatus 1 that performs a sputtering method, a target is installed inside a plasma generation region, which will be described later, for example. Further, for example, the present invention can be applied to a plasma processing apparatus 1 that performs a surface processing process (for example, an etching process or an ashing process) that performs a predetermined process on the surface of the base material S using plasma.

<Configuration of plasma processing apparatus 1>
FIG. 1 is a cross-sectional view schematically showing the configuration of a plasma processing apparatus 1 according to the first embodiment. As shown in FIG. 1, the plasma processing apparatus 1 includes a housing 10, an outer cover 20, an inner cover 30, an antenna 40, an insertion member 45, a holding section 50, a position adjustment mechanism 60, and a control section. 65, a storage section 68, a power supply section 70, and a chiller 75. Each figure referred to in the following explanation is a simplified illustration of only the main components necessary for explaining the embodiment for convenience of explanation, and well-known technical matters are explained for the sake of brevity. Omit as appropriate. Therefore, the plasma processing apparatus 1 in this embodiment may optionally include known constituent members that are not shown in the respective figures referred to.

The housing 10 constitutes a processing chamber 11 of the plasma processing apparatus 1 . The housing 10 has a main body 10a and a flange 10b. The main body 10a has a box shape with side surfaces and a bottom surface. The upper part of the main body 10a is open. The main body 10a may be electrically grounded. The flange 10b is arranged on the upper part of the main body 10a, and is attached to the main body 10a in an airtight manner. The flange 10b may be removably fixed to the main body 10a using screws or the like. For example, a vacuum seal member 91 may be interposed between the main body 10a and the flange 10b, and the vacuum seal member 91 may be a known member used for vacuum sealing, such as an O-ring. Further, the flange 10b is provided with one or more first openings 12 that communicate the processing chamber 11 with the external environment. The material for the main body 10a and the flange 10b is not particularly limited, and any known vacuum container material can be used.

A vacuum pump PO for reducing the pressure inside the processing chamber 11 is connected to the main body 10a. The main body 10a also has a supply port (not shown) for supplying processing gas into the processing chamber 11 from a processing gas supply section (not shown). The processing gas is, for example, argon, hydrogen, nitrogen, silane, or oxygen. Furthermore, the main body 10a may be provided with a pressure sensor (not shown) that measures the atmospheric pressure inside the processing chamber 11. When all the first openings 12 provided in the flange 10b are closed (hermetically sealed) by the outer cover 20, exhaust is performed by the vacuum pump PO, so that the inside of the processing chamber 11 is The pressure is maintained at a pressure suitable for plasma processing.

Further, in the processing chamber 11, a stage 15 is arranged on which a base material S to be processed by the plasma processing apparatus 1 is placed. The stage 15 is electrically insulated from the housing 10 and is grounded. The base material S is transported between the stage 15 and a known load lock chamber (not shown), for example, by a transport mechanism. The base material S may be, for example, a glass substrate or a synthetic resin substrate used for liquid crystal panel displays, organic EL (Electro Luminescence) panel displays, and the like. Further, the base material S may be a semiconductor substrate used for various purposes. Using the plasma processing apparatus 1, a film such as a barrier (moisture-proof) film can be formed on the base material S, for example.

One outer cover (vacuum cover) 20 corresponding to one first opening 12 is airtightly attached to the flange 10b so as to close the first opening 12. Further, the outer cover 20 may be removably fixed to the flange 10b using screws or the like. For example, a vacuum seal member 21 may be interposed between the outer cover 20 and the flange 10b. The vacuum seal member 21 may be a known member used for vacuum sealing, such as an O-ring. The outer cover 20 has at least one through hole 22 (described in detail later) that is different from a screw hole. The material of the outer cover 20 may be metal, for example, and may be the same as the material of the body 10a or the flange 10b.

The inner cover (antenna cover) 30 may be supported by being engaged with, for example, a portion of the flange 10b inside the first opening 12, so that the inner cover 30 can connect the processing chamber 11 and the outer cover 20. Spatially divide between. By attaching the inner cover 30 inside the first opening 12, the internal space of the housing 10 is defined and a plasma generation region is formed inside the housing 10. This plasma generation region becomes the processing chamber 11.

When the inner cover 30 is supported inside the first opening 12 , the inner cover 30 has a bottom portion 31 having a convex shape toward the processing chamber 11 side, and a collar portion 35 continuously extending from the end of the bottom portion 31 . have The inner cover 30 may have a second opening 32 that opens toward the outer cover 20 that is attached to the flange 10b. The second opening 32 may be formed by the inner wall surface of the collar portion 35 that is continuous with the inner wall surface of the bottom portion 31 . The flange portion 35 is a portion that is bent toward the outer wall side of the bottom portion 31, in other words, in a direction away from the second opening 32, and has an outwardly projecting shape.

For example, the flange 10b has a protrusion 13 shaped to protrude into the first opening 12, and the flange 35 of the inner cover 30 is hooked to the protrusion 13 of the flange 10b, so that the inner A cover 30 may be supported within the first opening 12 . Inner cover 30 may be formed from a dielectric material, such as alumina or quartz.

In a state where the inner cover 30 is supported inside the first opening 12, the surrounding space 33 surrounded by at least the outer cover 20 and the inner cover 30 is located on the opposite side of the processing chamber 11 with respect to the inner cover 30. It is formed. In the plasma processing apparatus 1 shown in FIG. 1, the surrounding space 33 is surrounded by the flange 10b in addition to the outer cover 20 and the inner cover 30. Further, in this specification, a space that is partially surrounded by the inner wall of the bottom portion 31 of the inner cover 30 and is opened at the second opening 32 is referred to as a partially open space 34 . The partially open space 34 constitutes a part of the enclosed space 33. It can also be said that the partially open space 34 is a space located in the enclosed space 33 closer to the bottom 31 than the edge of the second opening 32 (inner wall of the collar 35).

The antenna 40 generates inductively coupled plasma within the processing chamber 11 . The antenna 40 is arranged within the surrounding space (antenna accommodation space) 33. In particular, at least a portion of antenna 40 is housed in partially open space 34 . The material and structure of the antenna 40 are not particularly limited, and known materials and structures for general antennas can be used.

The insertion member 45 is inserted into the through hole 22 provided in the outer cover 20 and connected to the antenna 40 . In this embodiment, the insertion member 45 is a part of the antenna 40. That is, in this embodiment, when the antenna 40 is attached to the plasma processing apparatus 1, a part of the antenna 40 is located within the surrounding space 33, and the remaining part is continuously penetrated from the part located within the surrounding space 33. It extends through the hole 22 to the outside environment, with the end of the antenna 40 exposed to the outside environment. Thereby, the number of parts of the plasma processing apparatus 1 can be reduced. The antenna 40 has, for example, a shape in which the vicinity of both ends of a cylindrical conductor is bent, and includes an elongated part 41 (see FIG. 2) having an elongated shape located in a region between the bent parts, and a part between the bent part and the end. The insertion member 45 may be located in a region between the two parts. However, the insertion member 45 may be a member different from the antenna 40.

The holding portion 50 holds the insertion member 45 so that the insertion member 45 can be displaced while airtightly sealing the surrounding space 33 from the external environment. Further, the holding portion 50 may have insulation properties, and in this case, the insertion member 45 and the outer cover 20 can be electrically insulated from each other. In the example shown in FIG. 1, holding portions 50 are shown at two locations. Regarding the detailed constituent elements of the holding part 50, which will be explained below, in FIG. It may have a configuration.

The holding portion 50 can airtightly seal the through hole 22 via the vacuum seal member 51. The holding portion 50 has an insertion opening 52 through which the insertion member 45 is inserted. Further, the holding section 50 may further include a vacuum seal member 53 that airtightly seals between the holding section 50 and the insertion member 45 at the insertion opening 52. For example, the holding part 50 may hold the insertion member 45 so that the insertion member 45 is slidable. In this case, the insertion member 45 may be held in the holding part while keeping the inside of the housing 10 in an airtight state. 50. The vacuum seal member 53 may be, for example, a double O-ring. Further, the vacuum seal member 53 may be grease applied to the inner surface of the insertion hole 52. The holding part 50 is not particularly limited in its specific structure as long as it can hold the insertion member 45 so that the insertion member 45 can slide while keeping the inside of the housing 10 in an airtight state.

The holding part 50 is not limited to the above example, and may be configured using, for example, a flexible member or a member having an expandable and contractible structure. The holding part 50 may have a bellows, for example, and in this case, one end of the bellows may be hermetically connected to the surface of the outer cover 20 on the side of the surrounding space 33. The other end of the bellows may be airtightly connected to the outer peripheral surface of the insertion member 45. By expanding and contracting the bellows following the displacement of the antenna 40, the insertion member 45 can be displaced while airtightly sealing the surrounding space 33 from the external environment. Moreover, even if the pressure in the surrounding space 33 is reduced and the outer cover 20 is bent toward the surrounding space 33, the insertion member 45 is difficult to follow the deformation of the outer cover 20. This is because the deflection of the outer cover 20 is offset by the expansion and contraction of the bellows. As a result, even when the outer cover 20 is bent, the position of the antenna 40 can be easily maintained.

Note that one end of the bellows is airtightly connected to the surface of the outer cover 20 facing the external environment, and the other end of the bellows is connected to the outer periphery of the portion of the insertion member 45 that protrudes from the through hole 22 toward the external environment. It may also be connected hermetically to the surface. Even in such a configuration example, the same effects as described above can be achieved. In the following description, an example in which the holding part 50 holds the insertion member 45 so that the insertion member 45 is slidable will be described as the plasma processing apparatus 1 according to the present embodiment.

The insertion member 45 has a sliding contact portion 46 that comes into sliding contact with the holding portion 50 . For example, the vacuum seal member 53 included in the holding section 50 contacts the sliding contact section 46 . The sliding contact portion 46 may be formed on at least a portion of the surface of the insertion member 45. The surface roughness of the sliding contact portion 46 may be smaller than the surface roughness of a portion of the antenna 40 (for example, the elongated portion 41) disposed within the surrounding space 33. This improves the adhesion at the contact portion between the holding portion 50 and the sliding contact portion 46, for example, at the portion where the vacuum seal member 53 and the sliding contact portion 46 contact each other. As a result, the airtightness of the housing 10 is maintained well.

The position adjustment mechanism 60 adjusts the position of the antenna 40 by displacing the insertion member 45 with the outer cover 20 attached to the housing 10. The position adjustment mechanism 60 includes a connecting section 61 and a driving section 62. The connecting portion 61 is connected to a portion of the insertion member 45 that is exposed to the external environment. The drive section 62 displaces the insertion member 45 via the connection section 61 along the direction in which the insertion member 45 is inserted into the through hole 22 . The specific configuration of the connecting section 61 and the driving section 62 will be described later.

The position adjustment mechanism 60 is mounted on the surface of the outer cover 20 facing the external environment. Therefore, when attaching and detaching the antenna 40, the outer cover 20 and the position adjustment mechanism 60 can be easily removed while being integrated. The position adjustment mechanism 60 may be attached on the surface of the flange 10b.

The control unit 65 controls the position of the antenna 40 by controlling the operation of the drive unit 62. The control section 65 is electrically connected to the drive section 62. The control unit 65 outputs a command for controlling the operation of the drive unit 62. By controlling the position of the antenna 40 by the control unit 65, the position of the antenna 40 can be adjusted with better reproducibility than, for example, when the user manually adjusts the position of the antenna 40.

The storage unit 68 is a storage device that stores information necessary for the control unit 65 to control the drive unit 62 . However, the plasma processing apparatus 1 does not necessarily need to include the storage section 68. If the plasma processing apparatus 1 does not include the storage section 68, the control section 65 may be communicably connected to an external storage device that stores information necessary for controlling the drive section 62.

The power supply section 70 supplies power to the antenna 40. The power supply section 70 is connected to one end of the antenna 40. The other end of the antenna 40 is grounded via a variable capacitor 73 for adjusting impedance.

The power supply section 70 includes a high frequency power source 71 and a matching box 72. The high frequency power supply 71 outputs high frequency (for example, 13.56 MHz) power. By supplying high frequency power to the antenna 40 from the power supply unit 70, a high frequency induced magnetic field is generated around the antenna 40, and inductively coupled plasma of the gas introduced into the processing chamber 11 is generated. The matching box 72 improves power transmission efficiency from the high frequency power source 71 to the load by matching the impedance of the load to the high frequency power source 71 with the power source impedance.

The plasma processing apparatus 1 maintains the electrical connection between the power supply unit 70 and the antenna 40 and the electrical connection between the antenna 40 and the variable capacitor 73 even if the height (position) of the antenna 40 changes due to the position adjustment mechanism 60. It may have a configuration that allows the connection to be maintained. For example, the contact point between the wiring 74 from the power supply section 70 and the insertion member 45 and the contact point between the wiring 79 from the antenna 40 to the variable capacitor 73 and the insertion member 45 are slidable with respect to the insertion member 45. good. At least a portion of the wiring 74 and the wiring 79 may have flexibility. Furthermore, when the antenna 40 and the insertion member 45 are separate members, the wiring 74 and the wiring 79 may be connected to the antenna 40 through the inside of the insertion member 45.

Chiller 75 circulates a cooling medium (for example, cooling water) inside antenna 40 . For example, a Cu tube (internal piping) passes through the antenna 40 and the insertion member 45. The chiller 75 is connected to both ends of the Cu tube by tubes 76. Cooling water supplied from the chiller 75 to one end of the Cu tube via the tube 76 flows through the Cu tube and returns from the other end of the Cu tube to the chiller 75 via the tube 76, thereby cooling the antenna 40.

The plasma processing apparatus 1 may have a configuration in which the connection between the chiller 75 and the insertion member 45 can be maintained even if the height (position) of the antenna 40 changes by the position adjustment mechanism 60. The specific aspect of the configuration is not particularly limited. At least a portion of the tube 76 connecting the chiller 75 and the Cu tube may have flexibility. In this case, even if the position of the end of the Cu tube changes due to a change in the height of the antenna 40 by the position adjustment mechanism 60, the connection between the chiller 75 and the Cu tube is maintained.

FIG. 2 is an enlarged view of region II in FIG. In the plasma processing apparatus 1, as shown in FIG. 2, the antenna 40 includes an elongated portion 41 having an elongated shape. The elongated portion 41 has, for example, a cylindrical shape. Further, the outer cover 20 includes a first through hole 22a and a second through hole 22b as the through hole 22 described above.

In the plasma processing apparatus 1 in this embodiment, the insertion member 45, which is a part of the antenna 40, includes a first insertion member 45a and a second insertion member 45b. The first insertion member 45a is connected to the first end 41a side of the elongated portion 41 and inserted into the first through hole 22a. The second insertion member 45b is connected to the second end 41b side of the elongated portion 41 and inserted into the second through hole 22b.

In the plasma processing apparatus 1, the position adjustment mechanism 60 is provided individually corresponding to each of the first insertion member 45a and the second insertion member 45b. Specifically, the plasma processing apparatus 1 includes, for each antenna 40, a position adjustment mechanism 60 connected to the first insertion member 45a and a position adjustment mechanism 60 connected to the second insertion member 45b. . The control unit 65 controls the position of the antenna 40 on the first end 41a side and the position on the second end 41b side independently of each other. Thereby, the positional relationship between the first end 41a and the second end 41b of the antenna 40 can be adjusted.

The control unit 65 may operate the drive unit 62 to adjust the position of the antenna 40 within a range where the distance between the antenna 40 and the surface of the inner cover 30 facing the enclosed space 33 is 1 mm or more. By controlling the position of the antenna 40 within the above range by the control unit 65, the antenna 40 is prevented from coming into contact with the inner cover 30. Therefore, damage to the inner cover 30 and plasma abnormalities caused by the contact can be prevented.

For example, the distance between the surface of the end of the long portion 41 on the first end 41a side and the inner cover 30 is the first distance d1. The distance between the surface of the end of the antenna 40 on the second end 41b side and the inner cover 30 is defined as a second distance d2. In this embodiment, the elongated portion 41 of the antenna 40 has a cylindrical shape. Therefore, the distance between the antenna 40 and the surface of the inner cover 30 facing the surrounding space 33 is the shortest at the first end 41a or the second end 41b. The control unit 65 adjusts the position of the antenna 40 within a range where the first distance d1 and the second distance d2 are both 1 mm or more.

However, the control unit 65 may control the position of the antenna 40 in a range different from the above range. For example, the control unit 65 may control the position of the antenna 40 within a range where the distance between the bottom surface of the bottom portion 31 and the antenna 40 is 1 mm or more. The bottom surface of the bottom portion 31 herein refers to the surface of the bottom portion 31 facing the surrounding space 33 and is the portion located farthest from the outer cover 20. The bottom portion 31 has a U-shape in a cross-sectional view taken perpendicularly to the longitudinal direction of the elongated portion 41, and the elongated portion 41 is accommodated in the partially open space 34 described above. Thereby, the elongated portion 41 can be placed at a position relatively close to the base material S, and plasma can be efficiently generated in the processing chamber 11. Even in this case, the control unit 65 controls the position of the antenna 40 within the above range, thereby preventing the antenna 40 from coming into contact with the inner cover 30. Note that the position of the through hole 22 of the outer cover 20 and the mounting position of the inner cover 30 are set so that the distance between the surface of the long part 41 of the antenna 40 and the side wall of the bottom part 31 of the inner cover 30 is 1 mm or more. It's good that it has been done. According to the above configuration, it is possible to prevent damage to the inner cover 30 and generation of abnormal plasma due to contact between the antenna 40 and the inner cover 30.

For example, when starting up the plasma processing apparatus 1 (before energizing the antenna 40), the control unit 65 brings the antenna 40 into contact with the bottom surface of the bottom portion 31, and controls the position of the antenna 40 based on that position. Good too. In this case, the drive unit 62 may include, for example, a servo motor as a mechanism for controlling the position of the antenna 40. Furthermore, the storage unit 68 may store data indicating the relationship between the amount of rotation of the servo motor and the amount of displacement of the antenna 40. The control unit 65 can control the position of the antenna 40 by recognizing the distance between the bottom surface of the bottom part 31 and the antenna 40 from the amount of rotation of the servo motor.

Alternatively, the plasma processing apparatus 1 may include a sensor that outputs a signal according to the first distance d1 and the second distance d2. In that case, the control unit 65 controls the position of the antenna 40 as described above according to the output of the sensor.

The control unit 65 may control the position of the antenna 40 within a range where the difference between the first distance d1 and the second distance d2 is within 1 mm. If the difference between the first distance d1 and the second distance d2 is greater than 1 mm, the antenna 40 may be deformed. In the plasma processing apparatus 1, the control unit 65 controls the position of the antenna 40 as described above, thereby reducing the possibility that the antenna 40 will be deformed.

The antenna 40 has a sliding contact portion 46 over the entire range of sliding contact with the holding portion 50, corresponding to the range in which the insertion member 45 is displaced by operating the drive portion 62 based on a command from the control portion 65. It's okay to stay. In other words, the control unit 65 may operate the drive unit 62 so as to adjust the position of the antenna 40 within the range in which the sliding contact portion 46 is formed.

If a portion of the insertion member 45 other than the sliding contact portion 46 comes into contact with the holding portion 50, particularly the vacuum seal member 53, the airtightness within the housing 10 may deteriorate. In the plasma processing apparatus 1, the controller 65 operates the drive unit 62 as described above, thereby maintaining airtightness within the housing 10 and preventing gas leakage.

FIG. 3 is an end view taken along the line III-III in FIG. 1. The housing 10 has a plurality of first openings 12. In the example shown in FIG. 3, four first openings 12 are provided in the flange 10b. However, the number of first openings 12 provided in the flange 10b is not limited to this. The plasma processing apparatus 1 includes a number of outer covers 20 and inner covers 30 corresponding to the plurality of first openings 12 . Furthermore, in the plasma processing apparatus 1, an antenna 40 is installed in each of the plurality of first openings 12.

Further, in this embodiment, the plasma processing apparatus 1 includes a position adjustment mechanism 60 and a power supply section 70 corresponding to each of the antennas 40. The plasma processing apparatus 1 may include only one control section 65 and one storage section 68, or may include one for each position adjustment mechanism 60.

<Configuration of position adjustment mechanism 60>
FIG. 4 is a cross-sectional view schematically showing an example of the configuration of the position adjustment mechanism 60 according to the first embodiment. FIG. 5 is a sectional view taken along the line VV in FIG. 4. As shown in FIGS. 4 and 5, in the position adjustment mechanism 60, the drive section 62 includes a servo motor 62a, a rotating shaft 62b, a gear 62c, and a support plate 62d. Further, the connecting portion 61 includes a gear grooved plate 61a, a guide rail 61b, a slide plate 61c, a connecting member 61d, and an insulating plate 61e.

The servo motor 62a is a power source whose rotation amount is controlled by the control unit 65. The rotating shaft 62b is rotated by the power of the servo motor 62a. The gear 62c rotates together with the rotating shaft 62b and transmits the rotation of the rotating shaft 62b to the outside. The support plate 62d supports the servo motor 62a.

The gear grooved plate 61a is a plate having a gear groove that meshes with the gear 62c. The guide rail 61b is a rail substantially perpendicular to the surface of the outer cover 20. The slide plate 61c slides along the guide rail 61b. The slide plate 61c is attached to the gear grooved plate 61a. Therefore, the gear grooved plate 61a moves in a direction substantially perpendicular to the surface of the outer cover 20 as the slide plate 61c moves along the guide rail 61b due to the rotation of the gear 62c.

The connecting member 61d is connected to the insertion member 45. The connecting member 61d is attached to the gear grooved plate 61a via an insulating plate 61e having insulation properties. Therefore, the control unit 65 can control the position of the insertion member 45 and further the antenna 40 by controlling the amount of rotation of the servo motor 62a.

At least a portion of the connecting portion 61 has insulation properties. In the example shown in FIGS. 4 and 5, the insulating plate 61e has insulation properties. Therefore, the possibility that the servo motor 62a is energized from the insertion member 45 can be reduced, and the possibility that the power supplied to the servo motor 62a will affect the antenna 40 can be reduced. However, in the connection portion 61, components other than the insulating plate 61e may have insulation properties. In that case, the connecting portion 61 does not need to include the insulating plate 61e.

As described above, in the plasma processing apparatus 1, the positions of the plurality of antennas 40 can be adjusted individually without opening the processing chamber 11 to the atmosphere. Therefore, the height of the antenna 40 can be easily adjusted. For example, before starting mass production of products formed into films on the substrate S using the plasma processing apparatus 1, the film formation rate can be observed and the position of the antenna 40 can be determined as a film formation condition. As a result, the time required to start up the plasma processing apparatus 1 can be shortened.

Furthermore, in the plasma processing apparatus 1, the outer cover 20 is airtightly attached to the housing 10 via a vacuum seal member 21. Therefore, even if the inner cover 30 is damaged due to impact or the like, the possibility of gas leaking to the external environment can be reduced. The flange 35 of the inner cover 30 may be supported without being fixed to the protrusion 13 of the flange 10b, and when the outer cover 20 is removed, the inner cover 30 is exposed to the outside environment through the first opening 12. can be taken out. Therefore, the plasma processing apparatus 1 can be provided with highly improved maintainability. Furthermore, in the plasma processing apparatus 1, if the inner cover 30 is installed without screwing, etc., even when the inside of the processing chamber 11 is depressurized, cracks or deformation starting from the screwed parts may occur on the inner cover. 30 can be significantly reduced.

(Other configurations)
In the plasma processing apparatus 1, the position adjustment mechanism 60 is not limited to the example described above, and may be any mechanism that can displace the position of the antenna 40 (more specifically, the position of the insertion member 45), and may have a specific configuration. is not particularly limited. As the position adjustment mechanism 60, a known mechanism can be applied as appropriate. The position adjustment mechanism 60 may have a configuration that allows the user to manually adjust the position of the antenna 40.

In the plasma processing apparatus 1 in one embodiment, the pressure inside the processing chamber 11 is reduced and the surrounding space 33 is also reduced in pressure by evacuation using the vacuum pump PO. This is because the portion where the flange 35 of the inner cover 30 and the protrusion 13 of the flange 10b contact each other is not vacuum-sealed, and is connected to the processing chamber 11 through the gap between the flange 35 and the protrusion 13. This is because they communicate with the surrounding space 33. That is, the processing chamber 11, which is a plasma generation area, and the surrounding space 33, which is a non-plasma generation area, are separated from each other by the inner cover 30 attached to the inside of the first opening 12, but they are spatially separated from each other. Not isolated. The surrounding space 33 is narrower than the processing chamber 11 and is an area where it is difficult to generate and maintain plasma (plasma non-generation area). When electricity is being applied to generate plasma in the processing chamber 11, the atmospheric pressure of the surrounding space 33 may be, for example, 1 Pa to 100 Pa. The surrounding space 33 can be a region in which it is difficult to generate plasma (a non-plasma generation region).

In the plasma processing apparatus 1 in one embodiment, the portion where the flange 35 of the inner cover 30 and the protrusion 13 of the flange 10b contact each other is vacuum-sealed, and the inside of the processing chamber 11 and the inside of the surrounding space 33 are separately separated. It may be designed to exhaust air.

[Embodiment 2]
Other embodiments of the invention will be described below. For convenience of explanation, members having the same functions as the members described in the above embodiment are given the same reference numerals, and the description thereof will not be repeated.

FIG. 6 is a diagram showing the configuration of a position adjustment mechanism 60A according to the second embodiment. FIG. 7 is a sectional view taken along the line VII-VII in FIG. However, in FIG. 7, components located closer to the front of the paper than the cross section taken along the line VII-VII in FIG. 6 are also indicated by dashed dotted lines. As shown in FIGS. 6 and 7, the position adjustment mechanism 60A includes a connecting portion 61A and a driving portion 62A instead of the connecting portion 61.

The drive unit 62A differs from the drive unit 62 only in that it includes a rotary plate 62e instead of the gear 62c. The rotary plate 62e, like the gear 62c, rotates together with the rotary shaft 62b and transmits the rotation of the rotary shaft 62b to the outside.

The connecting portion 61A is different from the connecting portion 61 in that it includes a movable plate 61f instead of the gear grooved plate 61a and further includes a stepped bolt 61g. The movable plate 61f is rotatably connected to the rotating plate 62e around an axis substantially parallel to the rotating shaft 62b.

Furthermore, the connecting portion 61A has insulating plates 61e on both sides of the connecting member 61d. A movable plate 61f is connected to one insulating plate 61e by a stepped bolt 61g. The movable plate 61f is rotatable relative to the insulating plate 61e around the central axis of the stepped bolt 61g. A slide plate 61c is connected to the other insulating plate 61e.

With the above configuration, in the position adjustment mechanism 60A, the movable plate 61f is connected to the slide plate 61c via the connecting member 61d and the insulating plates 61e located on both sides thereof. Therefore, the movement of the movable plate 61f due to the rotation of the rotary plate 62e is a vertical movement such that the slide plate 61c moves along the guide rail 61b. Therefore, the position adjustment mechanism 60A also allows the control section 65 to control the position of the antenna 40 by controlling the drive section 62A.

[Embodiment 3]
In the first embodiment, the plurality of antennas 40 were not electrically connected to each other and were independent. However, two or more of the plurality of antennas 40 may be electrically connected to each other.

FIG. 8 is a diagram showing a first example in which a plurality of antennas 40 are electrically connected to each other. In the first example, the plasma processing apparatus 1 includes two power supply units 70. Two antennas 40 are connected in parallel to each of the two power supply units 70. Each antenna 40 is grounded via a variable capacitor 73 for adjusting impedance.

FIG. 9 is a diagram showing a second example in which a plurality of antennas 40 are electrically connected to each other. In the second example, the plasma processing apparatus 1 includes two power supply units 70. Two antennas 40 are connected in series to each of the two power supply units 70. A variable capacitor 73 is arranged between two antennas 40 that are connected in series.

FIG. 10 is a diagram showing a third example in which a plurality of antennas 40 are electrically connected to each other. In the third example, the plasma processing apparatus 1 includes a single power supply section 70. An antenna group in which two antennas 40 are connected in series is connected in parallel to a single power supply unit 70 . In each antenna group, a variable capacitor 73 is arranged between two antennas 40 that are connected in series.

Further, three or more antennas 40 may be electrically connected to each other. Furthermore, all the antennas 40 included in the plasma processing apparatus 1 may be electrically connected to each other.

In the plasma processing apparatus 1, the control unit 65 can appropriately adjust the position of each antenna 40 even when the plurality of antennas 40 are electrically connected to each other. In this case, the number of power supply units 70 can be made smaller than the number of antennas 40. Therefore, the number of parts of the plasma processing apparatus 1 can be reduced.

[Embodiment 4]
In the plasma processing apparatus 1, the storage unit 68 may store position setting information that presets the correspondence between the power input to the antenna 40 and the adjustment position of the antenna. In this case, the control unit 65 controls the position of the antenna 40 based on the position setting information stored in the storage unit 68 in accordance with the power supplied to the antenna 40 from the power supply unit 70.

The appropriate position of antenna 40 is highly dependent on the power applied to antenna 40. Therefore, the control unit 65 can simplify control by controlling the position of the antenna 40 based on the position setting information.

Further, as described above, the housing 10 has a plurality of first openings 12. The control unit 65 independently controls the positions of the plurality of antennas 40 installed in each of the plurality of first openings 12 based on the position setting information. Thereby, even if there are variations in the input power for each antenna 40, the position of the antenna 40 can be adjusted to an appropriate position according to the input power for each antenna 40.

[Verification test]
FIG. 11 is a diagram for explaining an example of the test results of the plasma processing apparatus 1 according to the first embodiment described above.

In the verification test, a film formation process was performed to form a SiO ₂ film on a silicon substrate as the base material S using the plasma processing apparatus 1 according to the first embodiment described above under the following test conditions. That is, as test conditions, the temperature of stage 15 was set to 290° C., and the flow rates of silane (SiH ₄ ) and oxygen were set to 300 sccm and 400 sccm, respectively. Further, the pressure inside the processing chamber 11 was set to 2.7 Pa, and the power of the 13.56 MHz high frequency power source (power source) 71 was set to 1.1 kW (number of antennas: 4). The pitch in the array direction of the four installed antennas 40 (hereinafter referred to as "antenna array direction") was 100 mm. The variation in antenna current values measured at both ends of each of the four antennas 40 was ±4.4%.

Regarding the SiO ₂ film formed by the plasma processing apparatus 1, the film formation rate and refractive index distribution in the antenna alignment direction were measured. Specifically, measurements were performed on the SiO ₂ film located below between two adjacent antennas 40 among the four antennas 40. FIG. 11 shows the results of determining the deposition rate and refractive index of the SiO ₂ film at a total of five locations: the center position between the two antennas 40 and four locations 20 mm apart from the center position in the direction in which the antennas are lined up. . In FIG. 11, the 0 mm position on the horizontal axis of the graph is the center position between the two antennas 40.

As shown by the solid line and the dotted line in FIG. 11, extremely high uniformity in both the deposition rate and the refractive index of the SiO ₂ film was obtained. Furthermore, the refractive index of the formed SiO ₂ film for light with a wavelength of 632.8 nm is approximately 1.456, which indicates that a good SiO ₂ film close to a thermally oxidized silicon film can be obtained. It was confirmed. Note that the evaluation of the SiO ₂ film was performed using spectroscopic ellipsometry by forming the film on a φ4 inch (diameter 100 mm) silicon substrate. The positions (heights) of the two antennas 40 were adjusted as appropriate.

〔summary〕
A plasma processing apparatus according to aspect 1 of the present invention is a plasma processing apparatus including a processing chamber, and includes a casing provided with a first opening that communicates the processing chamber with an external environment; an outer cover that is airtightly attached to the housing via a vacuum seal member so as to close the opening of the housing and has a through hole; an inner cover supported so as to spatially divide the processing chamber and the outer cover; and an inner cover disposed in an enclosed space surrounded by at least the outer cover and the inner cover, and guided into the processing chamber. an antenna for generating coupled plasma; an insertion member inserted into the through hole and connected to the antenna; and the insertion member is displaced while airtightly sealing the surrounding space from the external environment. and a position adjustment mechanism that adjusts the position of the antenna by displacing the insertion member with the outer cover attached.

According to the above configuration, the position of the antenna can be adjusted by displacing the insertion member with the outer cover attached. Therefore, the height of the antenna can be easily adjusted. At the time of starting up the plasma processing apparatus, the height of the antenna can be easily adjusted in order to determine the film forming conditions, so the time required for starting up the plasma processing apparatus can be shortened. Furthermore, in the plasma processing apparatus, the outer cover is airtightly attached to the housing via a vacuum seal member. Therefore, even if the inner cover is damaged due to impact or the like, the possibility of gas leaking to the outside environment can be reduced.

In the plasma processing apparatus according to Aspect 2 of the present invention, in Aspect 1, the position adjustment mechanism includes a connection portion connected to a portion of the insertion member exposed to the external environment, and a a drive section that displaces the insertion member along the insertion direction of the insertion member into the through hole, the drive section is electrically connected to the drive section, and the position of the antenna is controlled by controlling the operation of the drive section. It further includes a control section for controlling.

According to the above configuration, the position of the antenna can be controlled by the control section. Therefore, compared to, for example, a case where the user manually adjusts the antenna position, the antenna position can be adjusted easily and with good reproducibility.

In the plasma processing apparatus according to Aspect 3 of the present invention, in Aspect 2, the insertion member is a part of the antenna, at least a part of the connection part and the holding part have insulating properties, and the antenna is , a sliding contact portion slidingly contacting the holding portion, and the sliding contact portion has a surface roughness smaller than that of a portion of the antenna disposed in the surrounding space.

According to the above configuration, good airtightness is maintained at the contact point between the holding part and the sliding contact part. Therefore, even when the insertion member is displaced in order to displace the antenna, it is difficult for gas to flow into the enclosed space from the external environment.

In the plasma processing apparatus according to aspect 4 of the present invention, in the aspect 3, the antenna corresponds to a range in which the insertion member is displaced by operating the drive unit based on a command from the control unit. The sliding contact portion is provided over a range of sliding contact with the holding portion.

According to the above configuration, it is possible to easily maintain airtightness by the holding portion.

In the plasma processing apparatus according to Aspect 5 of the present invention, in Aspect 4, the control unit is configured such that a distance between the forming range of the sliding contact portion and the surface of the inner cover facing the surrounding space and the antenna is 1 mm or more. The drive unit is operated so as to adjust the position of the antenna within a range where

According to the above configuration, the control unit controls the position of the antenna within the above range. This prevents the antenna from contacting the inner cover while maintaining the airtightness provided by the holding portion. Therefore, it is possible to reduce the possibility that the inner cover will be damaged and that an abnormality will occur in the plasma due to contact between the antenna and the inner cover.

In the plasma processing apparatus according to aspect 6 of the present invention, in any one of aspects 2 to 5 above, the inner cover has a bottom portion having a convex shape toward the processing chamber side and a bottom portion opening toward the outer cover side. 2 openings, the second opening is inside a partially open space that is partially surrounded by the inner wall of the bottom of the inner cover and is open at the second opening. At least a portion of the antenna is accommodated through the bottom part, and the control part controls the position of the antenna within a range where the distance between the bottom surface of the bottom part and the antenna is 1 mm or more.

According to the above configuration, even when at least a portion of the antenna is housed in the partially open space, the control unit controls the position of the antenna within the above range, thereby preventing the antenna from coming into contact with the inner cover. Prevented.

In the plasma processing apparatus according to aspect 7 of the present invention, in any one of aspects 2 to 6, the antenna includes an elongated portion having an elongated shape, and the outer cover has a first through hole and The insertion member has a second through hole, and the insertion member includes a first insertion member connected to the first end side of the elongated portion and inserted into the first through hole; a second insertion member connected to the second end side and inserted into the second through hole, and the position adjustment mechanism is connected to each of the first insertion member and the second insertion member. The control unit controls a position on the first end side and a position on the second end side of the antenna independently of each other.

According to the above configuration, the positions of both the first end and the second end of the antenna can be easily adjusted.

In the plasma processing apparatus according to an eighth aspect of the present invention, in the seventh aspect, the insertion member is a part of the antenna.

According to the above configuration, the number of parts of the plasma processing apparatus can be reduced.

In the plasma processing apparatus according to aspect 9 of the present invention, in the aspect 7 or 8, a distance between the end surface of the antenna on the first end side and the inner cover is a first distance, and Assuming that the distance between the end surface on the second end side and the inner cover is the second distance, the control unit sets the range such that the difference between the first distance and the second distance is within 1 mm. to control the position of the antenna.

According to the above configuration, it is possible to effectively reduce the possibility that the antenna will be deformed due to the significantly different positions of the first end and the second end of the antenna.

The plasma processing apparatus according to aspect 10 of the present invention, in any one of aspects 2 to 9 above, includes a power supply unit that supplies power to the antenna, and the control unit controls the power input to the antenna and the The position of the antenna is controlled in accordance with the power input from the power supply unit to the antenna, based on position setting information in which a correspondence relationship with the adjustment position of the antenna is set in advance.

The proper location of the antenna is highly dependent on the power input to the antenna. According to the above configuration, the control unit controls the position of the antenna based on position setting information set in advance. This simplifies control.

In the plasma processing apparatus according to an eleventh aspect of the present invention, in the tenth aspect, the casing has a plurality of the first openings, and the control section controls the plurality of the first openings based on the position setting information. The positions of the plurality of antennas installed in each of the first openings are controlled independently from each other.

According to the above configuration, even if there are variations in the input power for each antenna, the position of the antenna can be easily adjusted to an appropriate position according to the input power for each antenna.

In the plasma processing apparatus according to aspect 12 of the present invention, in any one of aspects 1 to 11, the position adjustment mechanism is attached to the surface of the outer cover on the external environment side.

According to the above configuration, when attaching and detaching the antenna, the outer cover and the position adjustment mechanism can be easily removed while being integrated.

[Additional notes]
The present invention is not limited to the embodiments described above, and various modifications can be made within the scope of the claims, and embodiments obtained by appropriately combining technical means disclosed in different embodiments. are also included within the technical scope of the present invention.

1 Plasma processing apparatus 10 Housing 11 Processing chamber 12 First opening 20 Outer cover 21 Vacuum sealing member 22 Through hole 30 Inner cover 31 Bottom 32 Second opening 33 Surrounding space 34 Partially open space 40 Antenna 41 Long part 41a First end portion 41b Second end portion 45 Insertion member 45a First insertion member 45b Second insertion member 46 Sliding portion 50 Holding portion 60, 60A Position adjustment mechanism 61, 61A Connection portion 62, 62A Drive portion 65 Control unit 70 Power supply unit

Claims (12)

A plasma processing apparatus including a processing chamber,
a casing provided with a first opening that communicates the processing chamber with an external environment;
an outer cover airtightly attached to the housing via a vacuum seal member so as to close the first opening, and having a through hole;
an inner cover that has dielectric properties and is supported within the first opening so as to spatially divide between the processing chamber and the outer cover;
an antenna disposed in an enclosed space surrounded by at least the outer cover and the inner cover, and for generating inductively coupled plasma in the processing chamber;
an insertion member inserted into the through hole and connected to the antenna;
a holding part that holds the insertion member so that the insertion member is movable while airtightly sealing the surrounding space from the external environment;
A plasma processing apparatus comprising: a position adjustment mechanism that adjusts the position of the antenna by displacing the insertion member with the outer cover attached. The position adjustment mechanism displaces the insertion member along the insertion direction of the insertion member into the through hole via the connection portion connected to the portion of the insertion member exposed to the external environment and the connection portion. and a drive unit that causes
The plasma processing apparatus according to claim 1, further comprising a control section that is electrically connected to the drive section and controls the position of the antenna by controlling the operation of the drive section. The insertion member is a part of the antenna,
At least a portion of the connecting portion and the holding portion have insulation,
The antenna has a sliding contact portion that slides into contact with the holding portion,
The plasma processing apparatus according to claim 2, wherein the sliding contact portion has a surface roughness smaller than that of a portion of the antenna disposed in the surrounding space. The antenna has the sliding contact portion over a range in which the insertion member slides into contact with the holding portion, corresponding to a range in which the insertion member is displaced by operating the drive portion based on a command from the control portion. , The plasma processing apparatus according to claim 3. The control unit controls the drive so as to adjust the position of the antenna in a range where the sliding contact portion is formed and a distance between the antenna and the surface of the inner cover facing the surrounding space is 1 mm or more. 5. The plasma processing apparatus according to claim 4, wherein the plasma processing apparatus operates a part of the plasma processing apparatus. The inner cover has a bottom portion having a convex shape toward the processing chamber side and a second opening portion opening toward the outer cover side,
At least a portion of the antenna is inserted through the second opening into a partially open space that is partially surrounded by the inner wall of the bottom of the inner cover and is open at the second opening. accommodated,
The plasma processing apparatus according to claim 2, wherein the control unit controls the position of the antenna within a range where the distance between the bottom surface of the bottom portion and the antenna is 1 mm or more. The antenna includes an elongated portion having an elongated shape,
the outer cover has a first through hole and a second through hole,
The insertion member includes a first insertion member connected to a first end of the elongated portion and inserted into the first through hole, and a first insertion member connected to a second end of the elongated portion. a second insertion member inserted into the second through hole;
The position adjustment mechanism is connected to each of the first insertion member and the second insertion member,
The plasma processing apparatus according to claim 2, wherein the control unit controls a position on the first end side and a position on the second end side of the antenna independently of each other. The plasma processing apparatus according to claim 7, wherein the insertion member is a part of the antenna. The distance between the surface of the end of the antenna on the first end side and the inner cover is a first distance, and the distance between the surface of the end of the antenna on the second end side and the inner cover is a first distance. As the second distance,
The plasma processing apparatus according to claim 7, wherein the control unit controls the position of the antenna within a range where a difference between the first distance and the second distance is within 1 mm. comprising a power supply section that supplies power to the antenna,
The control unit adjusts the antenna according to the power input from the power supply unit to the antenna, based on position setting information in which a correspondence relationship between the power input to the antenna and the adjustment position of the antenna is set in advance. The plasma processing apparatus according to claim 2, wherein the position of the plasma processing apparatus is controlled. The casing has a plurality of the first openings,
The plasma processing apparatus according to claim 10, wherein the control unit independently controls the positions of the plurality of antennas installed in each of the plurality of first openings based on the position setting information. The plasma processing apparatus according to any one of claims 1 to 11, wherein the position adjustment mechanism is attached to a surface of the outer cover on the external environment side.

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