Plasma processing equipment

Abstract

To provide a plasma processing device that can easily achieve uniform plasma density in the longitudinal direction of an antenna.SOLUTION: A plasma processing device (1) includes a vacuum vessel (2), a high frequency window (3), and an antenna portion (AP). The antenna portion (AP) includes an antenna (7), a first conductor (9a), a second conductor (9b), a first capacitor portion (8a) that changes a first connection angle between the antenna (7) and the first conductor (9a), and a second capacitor portion (8b) that changes a second connection angle between the antenna (7) and the second conductor (9b).SELECTED DRAWING: Figure 3

Description

Technical Field

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[0001] The present disclosure relates to a plasma processing apparatus.

Background Art

[0002] There is known a plasma processing apparatus that generates plasma inside a vacuum chamber using an antenna. The plasma processing apparatus performs a predetermined plasma process using the generated plasma on a workpiece according to its type.

[0003] Also, in a plasma processing apparatus, there is known one provided with a moving drive unit that moves the position of an antenna.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] The plasma processing apparatus disclosed in Patent Document 1 is provided with an antenna whose distance from a workpiece can be changed, but there is room for improvement in achieving uniform plasma density in the longitudinal direction of the antenna.

[0006] The present disclosure has been made in view of the above problems, and an object thereof is to provide a plasma processing apparatus capable of easily achieving uniform plasma density in the longitudinal direction of an antenna.

Means for Solving the Problems

[0008] According to one aspect of this disclosure, a plasma processing apparatus can be provided that can easily achieve uniformity of plasma density in the longitudinal direction of an antenna. [Brief explanation of the drawing]

[0009] [Figure 1] This is a cross-sectional view of a plasma processing apparatus according to Embodiment 1 of this disclosure. [Figure 2] Figure 1 is a diagram illustrating the main components of the antenna section. [Figure 3] This figure illustrates an example of the configuration of the second capacitor section shown in Figure 2. [Figure 4] This diagram illustrates another example configuration of the second capacitor section described above. [Figure 5] This diagram illustrates an example of the operation of the plasma processing apparatus described above. [Figure 6] This diagram illustrates another example of operation of the plasma processing apparatus described above. [Figure 7] This figure illustrates an example of operation of the plasma processing apparatus 1 in a modified form. [Figure 8]This figure illustrates the main components of a plasma processing apparatus according to Embodiment 2 of this disclosure. [Figure 9] This figure illustrates the main components of a plasma processing apparatus according to Embodiment 3 of this disclosure. [Modes for carrying out the invention]

[0010] [Embodiment 1] Hereinafter, one embodiment of the present disclosure will be specifically described with reference to Figure 1. Figure 1 is a cross-sectional view of a plasma processing apparatus according to Embodiment 1 of the present disclosure.

[0011] In the following explanation, a plasma processing apparatus 1 is used as an example to describe a film deposition process in which a predetermined film is deposited on the surface of a workpiece H1 using a plasma CVD (Chemical Vapor Deposition) method with inductively coupled plasma as the predetermined plasma treatment.

[0012] However, this disclosure can be applied to a plasma processing apparatus that performs a film deposition process, for example, by sputtering to deposit a predetermined film on a workpiece H1, as a predetermined plasma treatment. Furthermore, this disclosure can be applied to a plasma processing apparatus that performs a surface processing process, for example, etching or ashing, on the surface of a workpiece H1 using plasma, as a predetermined plasma treatment. In the plasma processing apparatus 1 that performs sputtering, the target is placed inside the plasma.

[0013] <Configuration of Plasma Processing Device 1> As shown in FIG. 1, the plasma processing apparatus 1 of the first embodiment includes a vacuum chamber 2, a high-frequency window 3, a potential adjustment layer 6, and an antenna section AP. Inside the vacuum chamber 2, a processing chamber 21 that is evacuated and into which a gas is introduced is formed. The vacuum chamber 2 is, for example, a housing made of metal. An opening 23 that penetrates in the thickness direction is formed in the wall surface 22 of the vacuum chamber 2. The vacuum chamber 2 is electrically grounded. An object to be processed H1 is accommodated inside the vacuum chamber 2. Further, in the plasma processing apparatus 1, the object to be processed H1 is transported (not shown) between a stage H provided in the processing chamber 21 and a known load lock chamber by a transport mechanism.

[0014] The gas introduced into the processing chamber 21 may be selected according to the processing content to be applied to the object to be processed H1 accommodated in the processing chamber 21. For example, when forming a film on the object to be processed H1 by the plasma CVD method, the gas is a source gas or a gas diluted with a dilution gas such as H2. More specifically, when the source gas is SiH4, a Si film can be formed; when it is SiH4 + NH3, a SiN film can be formed; when it is SiH4 + O2, a SiO2 film can be formed; and when it is SiF4 + N2, a SiN:F film (fluorinated silicon nitride film) can be formed on the object to be processed H1, respectively.

[0015] The object to be processed H1 can be, for example, a glass substrate or a synthetic resin substrate used for a liquid crystal panel display, an organic EL (Electro Luminescence) panel display, etc. Also, the object to be processed H1 can be a semiconductor substrate used for various applications. The plasma processing apparatus 1 forms a predetermined film such as a barrier (moisture-proof) film on the object to be processed H1 by the above-described predetermined plasma processing.

[0016] <U <Configuration of the high-frequency window 3> The high-frequency window 3 has a metal plate 4 and a dielectric plate 5. The high-frequency window 3 introduces a high-frequency magnetic field that generates plasma inside the processing chamber 21 of the vacuum chamber 2 into the processing chamber 21 of the vacuum chamber 2 through the opening 23. The metal plate 4 and the dielectric plate 5 are disposed above the opening 23 of the vacuum chamber 2.

[0017] The metal plate 4 is provided on the wall surface 22 of the vacuum chamber 2 so as to close the opening 23. A plurality of slits 41 penetrating the metal plate 4 are formed in the metal plate 4. The metal plate 4 is arranged substantially parallel to the surface of the workpiece W1. The metal plate 4 is made of, for example, one metal selected from the group including copper, aluminum, zinc, nickel, tin, silicon, titanium, iron, chromium, niobium, carbon, molybdenum, tungsten, or cobalt, or an alloy thereof.

[0018] The dielectric plate 5 is provided in contact with the metal plate 4 from the outside of the vacuum chamber 2 so as to close the plurality of slits 41, and overlaps the surface of the metal plate 4 on the antenna portion AP side. Thereby, the dielectric plate 5 is supported by the metal plate 4, deformation of the dielectric plate 5 can be suppressed, and the strength of the dielectric plate 5 can be substantially improved.

[0019] The entire dielectric plate 5 is made of a dielectric material, and the dielectric plate 5 has a flat plate shape. The material constituting the dielectric plate 5 may be an inorganic material such as ceramics such as alumina, silicon carbide or silicon nitride, quartz glass, non-alkali glass, or a resin material such as a fluororesin such as Teflon (registered trademark).

[0020] The high-frequency magnetic field generated from the antenna portion AP passes through the dielectric plate 5, the potential adjustment layer 6, and the plurality of slits 41 and is supplied to the inside of the processing chamber 21. The vacuum inside the processing chamber 21 is maintained by the metal plate 4 closing the opening 23 of the vacuum chamber 2 and the dielectric plate 5 closing the plurality of slits 41.

[0021] <Configuration of the potential adjustment layer 6> The potential adjustment layer 6 is composed of one metal selected from the group including, for example, copper, aluminum, zinc, nickel, tin, silicon, titanium, iron, chromium, niobium, carbon, molybdenum, tungsten, or cobalt, or an alloy thereof. The potential adjustment layer 6 is formed on the surface of the dielectric plate 5 on the antenna 7 side. In other words, the potential adjustment layer 6 is formed on the surface of the dielectric plate 5 opposite to the side that is in contact with the metal plate 4. Specifically, the potential adjustment layer 6 is formed in a film-like manner so as to cover the entire surface of the dielectric plate 5 by vacuum deposition or plating.

[0022] However, the potential adjustment layer 6 only needs to be formed on the surface of the dielectric plate 5 so as to cover all of the multiple slits 41, and may be formed on an area of ​​the surface of the dielectric plate 5 excluding a portion. Furthermore, if the potential adjustment layer 6 is formed on an area of ​​the surface of the dielectric plate 5 excluding a portion, the size of the potential adjustment layer 6 can be reduced, thereby reducing the manufacturing cost of the plasma processing apparatus 1.

[0023] The potential adjustment layer 6 is connected to a predetermined potential, for example, ground G1, and is grounded. This, combined with the fact that the dielectric plate 5 overlaps the metal plate 4 so as to cover multiple slits 41, allows the potential adjustment layer 6 to efficiently and more reliably block the electric field from the antenna section AP toward the inside of the processing chamber 21. Therefore, it is possible to suppress the occurrence of electrostatic coupling between the plasma P1 generated inside the processing chamber 21 and the antenna section AP.

[0024] Thus, in this embodiment 1, the potential adjustment layer 6 can suppress the occurrence of electrostatic coupling, making it possible to generate a plasma P1 with suppressed electrostatic coupling components. Therefore, the generation of plasma due to electrostatic coupling is suppressed, and the mixing of plasma due to electrostatic coupling with the plasma due to inductive coupling is suppressed. As a result, the flow of charged particles due to the potential gradient between the plasma generated by electrostatic coupling and the high-frequency window 3, and the energy loss at the inner wall of the vacuum vessel 2 due to that flow can be reduced, and a high-density plasma P1 can be generated inside the processing chamber 21. In addition, the number of charged particles to which kinetic energy is imparted by the potential gradient can be reduced, reducing the inflow of unnecessary energy to the surface of the workpiece W1, and making it possible to reduce damage to the surface of the workpiece W1 during film formation and etching.

[0025] Furthermore, if the potential adjustment layer 6 is not formed on the dielectric plate 5, it may not be possible to sufficiently suppress the electrostatic coupling. In other words, the metal plate 4 allows the high-frequency magnetic field generated from the antenna section AP to pass through to the inside of the processing chamber 21, and can reduce the intrusion of electric fields from outside the processing chamber 21 into the inside of the processing chamber 21. However, if the potential adjustment layer 6 is not formed on the dielectric plate 5, the electric field generated from the antenna section AP passes through the dielectric plate 5 and the multiple slits 41, causing electrostatic coupling between the plasma P1 generated inside the processing chamber 21 and the antenna section AP.

[0026] Furthermore, since a potential adjustment layer 6 is provided on the dielectric plate 5, the electric field generated from the antenna AP can be blocked by the potential adjustment layer 6 regardless of the size of the slit 41 formed in the metal plate 4. As a result, even if the size of the slit 41 is large, it is possible to prevent the electric field generated from the antenna AP from entering the processing chamber 21. Therefore, a sufficiently large slit 41 can be formed in the metal plate 4, and the high-frequency magnetic field generated from the antenna AP can be efficiently supplied from the slit 41 into the processing chamber 21, thereby improving the generation efficiency of the plasma P1.

[0027] Alternatively, a non-metallic material, such as an oxide-based transparent conductive film, may be used instead of the potential adjustment layer 6. In this case, the combination of the transparent conductive film and the glass dielectric plate 5 allows for confirmation of the plasma emission distribution from the antenna AP side, and also enables confirmation of the plasma density distribution or the progress of the plasma processing. For example, the progress of etching can be confirmed.

[0028] <Configuration of the antenna AP> Using Figure 2, we will now specifically describe an example of the main components of the antenna section AP of this embodiment. Figure 2 is a diagram illustrating the main components of the antenna section shown in Figure 1. Note that in Figure 2, the dielectric plate 5 and the potential adjustment layer 6 are omitted from the illustration for the sake of simplicity.

[0029] As shown in Figures 1 and 2, the antenna section AP is located outside the vacuum container 2 and above the vacuum container 2. The antenna section AP comprises an antenna 7, a pair of conductors, a first conductor 9a and a second conductor 9b, a first capacitor section 8a connected between one end of the antenna 7 and the first conductor 9a, and a second capacitor section 8b connected between the other end of the antenna 7 and the second conductor 9b.

[0030] <Configuration of Antenna 7> Antenna 7 is composed of, for example, a bar-shaped cylindrical body that generates a high-frequency magnetic field. Specifically, antenna 7 is composed of a cylindrical member made of a metal material such as copper, aluminum, an alloy thereof, or stainless steel.

[0031] Furthermore, the antenna 7 is configured to be bendable. Specifically, the antenna 7 is provided with, for example, a straight section 7a1, a bent section 7b1, a straight section 7a2, a bent section 7b2, and a straight section 7a3 in sequence, from one end to the other end. The straight sections 7a1, 7a2, and 7a3 are configured to be straight and are installed facing one end, the center, and the other end of the processing chamber 21 of the vacuum container 2 in the longitudinal direction. In addition, these straight sections 7a1, 7a2, and 7a3 are constructed to be difficult to bend.

[0032] The bent sections 7b1 and 7b2 have, for example, a bellows structure. In other words, the bent sections 7b1 and 7b2 are designed to be easily bent. The bent section 7b1 allows the straight sections 7a1 and 7a2 to change positions relative to each other. That is, as illustrated in Figure 2, the bent section 7b1 allows the straight sections 7a1 and 7a2 to change from a straight shape to a non-straight shape. Similarly, the bent section 7b2 allows the straight sections 7a2 and 7a3 to change positions relative to each other. That is, as illustrated in Figure 2, the bent section 7b2 allows the straight sections 7a2 and 7a3 to change from a straight shape to a non-straight shape.

[0033] In the above description, an antenna 7 having linear sections 7a1, 7a2, and 7a3, and bent sections 7b1 and 7b2 was described. However, the antenna 7 of this disclosure is not limited to this, and only one having at least two linear sections and a bendable bent section provided between the two linear sections is required. Furthermore, since the antenna 7 is configured to bend in the longitudinal direction, the distance between the antenna and the high-frequency window can be partially and reliably changed, and the uniformity of the plasma density in the longitudinal direction of the antenna can be reliably achieved.

[0034] In addition to the above description, the antenna 7 itself can also be constructed using an elastically deformable metal material. In other words, this disclosure also allows for the use of an antenna that does not have a bent portion, but whose entire longitudinal direction is capable of bending.

[0035] <Configuration of the first conductor 9a and the second conductor 9b> The first conductor 9a and the second conductor 9b are made of cylindrical members made of metal materials such as copper, aluminum, alloys thereof, or stainless steel. The first conductor 9a and the second conductor 9b are part of a circuit for supplying high-frequency current to the antenna 7. Specifically, the first conductor 9a and the second conductor 9b are connected to a high-frequency power supply 10, and the second conductor 9b is grounded. In the antenna section AP, a high-frequency current with a frequency of, for example, 13.56 MHz is supplied to the antenna 7 from the high-frequency power supply 10. In the plasma processing apparatus 1, when a high-frequency current flows through the antenna 7, an induced electric field is generated inside the vacuum vessel 2, and an inductively coupled plasma P1 is produced.

[0036] <Configuration of the first capacitor section 8a and the second capacitor section 8b> The first capacitor section 8a is a member that connects one end of the antenna 7 to the first conductor 9a, and is a first connection section that can change the first connection angle θ1 (Figure 5 shown later), which is the connection angle between the antenna 7 and the first conductor 9a. The second capacitor section 8b is a member that connects the other end of the antenna 7 to the second conductor 9b, and is a second connection section that can change the second connection angle θ2 (Figure 5 shown later), which is the connection angle between the antenna 7 and the second conductor 9b.

[0037] The first capacitor section 8a comprises a rotating section 8a1 connected to one end of the linear section 7a1 and a main body section 8a2 connected to the first conductor 9a. The rotating section 8a1 and the main body section 8a2 are configured to be rotatable relative to each other. Similarly, the second capacitor section 8b comprises a rotating section 8b1 connected to the other end of the linear section 7a3 and a main body section 8b2 connected to the second conductor 9b. The rotating section 8b1 and the main body section 8b2 are configured to be rotatable relative to each other.

[0038] The rotating parts 8a1 and 8b1 are connected to a motor M1 as the first drive unit and a motor M2 as the second drive unit, respectively, via a drive mechanism (not shown). These motors M1 and M2 are included in the antenna unit AP and are each configured using known motors such as stepping motors or brushless DC motors.

[0039] Furthermore, the rotating parts 8a1 and 8b1 are driven by motors M1 and M2 according to operation instructions from the control unit C, causing them to rotate in predetermined directions relative to the main body 8a2 and 8b2, respectively. As a result, in this embodiment 1, the first connection angle θ1 and the second connection angle θ2 change according to the rotating parts 8a1 and 8b1. Consequently, the antenna 7 can change from a state parallel to the metal plate 4 of the high-frequency window 3, as shown in Figure 1, to a state bent relative to the metal plate 4, as shown in Figure 2 (details will be described later).

[0040] Furthermore, the control unit C is configured to simultaneously rotate motors M1 and M2 by the same amount in accordance with user instructions to an operation input unit (not shown). As a result, the first connection angle θ1 and the second connection angle θ2 change by the same amount.

[0041] In addition to the above explanation, depending on the structure and material of the antenna 7, the control unit C may also be configured to drive only one of the motors M1 or M2 according to instructions from the user, thereby changing only one of the first connection angle θ1 or the second connection angle θ2.

[0042] The first capacitor section 8a and the second capacitor section 8b are provided symmetrically on one end and the other end of the antenna 7, respectively, and have the same structure. Both the first capacitor section 8a and the second capacitor section 8b have a cylindrical structure, allowing cooling water W to circulate inside each. Therefore, the following explanation will mainly describe the second capacitor section 8b using Figure 3. Figure 3 is a diagram illustrating an example of the configuration of the second capacitor section 8b shown in Figure 2.

[0043] In Figure 3, the rotating part 8b1 and the main body part 8b2 of the second capacitor section 8b are constructed in a cylindrical shape using, for example, a synthetic resin such as polyphenylene sulfide or a ceramic such as alumina. The rotating part 8b1 and the main body part 8b2 are configured to rotate relative to each other via a gasket g. A cylindrical connecting member C4 is provided inside the rotating part 8b1, and the end of the linear part 7a3, which is the other end of the antenna 7, is connected to the connecting member C4. The second capacitor section 8b has a cylindrical second antenna electrode C2 connected to the other end of the antenna 7 via the connecting member C4. In other words, the second antenna electrode C2 extends from inside the rotating part 8b1 into inside the main body part 8b2.

[0044] A cylindrical connecting member C3 is provided inside the main body 8b2, and the end of the second conductor 9b is connected to the connecting member C3. The second capacitor section 8b has a cylindrical second conductor side electrode C1 connected to the other end of the antenna 7 via the connecting member C3. In the second capacitor section 8b, the second conductor side electrode C1 and the second antenna electrode C2 are configured to rotate while maintaining their relative positions and separated by a gap. Therefore, the second capacitor section 8b can supply high-frequency current to the antenna 7 while adjusting the mutual rotation of the second connection between the antenna 7 and the second conductor 9b, that is, the second connection angle θ2.

[0045] Similarly, the first capacitor section 8a has a first conductor-side electrode connected to the first conductor 9a and a first antenna electrode connected to a linear section 7a1 which is one end of the antenna. Furthermore, the first capacitor section 8a has a rotating section 8a1 and a main body section 8a2 that rotate relative to each other. Therefore, in the first capacitor section 8a, the first conductor-side electrode and the first antenna electrode are configured to rotate while maintaining their relative positions and separated by a gap. As a result, the first capacitor section 8a can supply high-frequency current to the antenna 7 while adjusting the relative rotation of the first connection between the antenna 7 and the first conductor 9a, that is, the first connection angle θ1.

[0046] In the plasma processing apparatus 1 of this embodiment 1, as described above, each part of the antenna section AP, namely the first conductor 9a, the first capacitor section 8a, the antenna 7, the second capacitor section 8b, and the second conductor 9b, is configured in a cylindrical shape. For this reason, the antenna section AP is configured to circulate cooling water W as a cooling medium using a chiller (not shown). As a result, in this embodiment 1, each part of the antenna section AP can be appropriately cooled to a predetermined temperature, and the plasma processing apparatus 1 can operate more appropriately.

[0047] Furthermore, in the second capacitor section 8b, the cooling water flowing through the gap between the second conductor side electrode C1 and the second antenna electrode C2 functions as a dielectric layer of the second capacitor section 8b. That is, in the second capacitor section 8b, the opposing length between the second conductor side electrode C1 and the second antenna electrode C2 constitutes the capacitor length. Similarly, in the first capacitor section 8a, the cooling water flowing through the gap between the first conductor side electrode and the first antenna electrode functions as a dielectric layer of the first capacitor section 8a. That is, in the first capacitor section 8a, the opposing length between the first conductor side electrode and the first antenna electrode constitutes the capacitor length.

[0048] In addition to the above description, insulating layers made of cylindrical dielectric material may be installed in the gap between the first conductor side electrode and the first antenna electrode and in the gap between the second conductor side electrode C1 and the second antenna electrode C2 to constitute the dielectric layers of the first capacitor section 8a and the second capacitor section 8b.

[0049] However, as described above, it is preferable to use cooling water W to construct the dielectric layers of the first capacitor section 8a and the second capacitor section 8b, as this allows for the construction of the plasma processing apparatus 1 at a lower cost compared to the case where the dielectric layers are provided separately.

[0050] <Another configuration of the second capacitor section 8b> Next, another configuration example of the second capacitor section 8b will be specifically explained using Figure 4. Figure 4 is a diagram illustrating another configuration example of the second capacitor section 8b described above.

[0051] As shown in Figure 4, in the second capacitor section 8b, the second conductor side electrode C1 includes, for example, a cylindrical electrode portion C1a and a disc-shaped electrode portion C1b. Electrode portion C1a is connected to the second conductor 9b via a connecting member C3. Electrode portion C1b is fixed to the end of electrode portion C1a.

[0052] The second antenna electrode C2 comprises, for example, a cylindrical electrode portion C2a and a disc-shaped electrode portion C2b. Electrode portion C2a is connected to the other end of the antenna 7, a linear portion 7a3, via a connecting member C4. Electrode portion C2b is fixed to the end of electrode portion C2a. Electrode portions C1b and C2b face each other within the main body portion 8b2, separated by a predetermined gap. In the second capacitor portion 8b, the cooling water W present in the space between electrode portions C1b and C2b functions as a dielectric layer of the second capacitor portion 8b.

[0053] <Configuration of Control Unit C> The control unit C is a functional block that includes, for example, a CPU (Central Processing Unit), RAM (Random Access Memory), ROM (Read Only Memory), etc., and controls each part of the plasma processing apparatus 1 according to information processing. Specifically, the control unit C performs drive control to control the rotational drive of motors M1 and M2 based on instructions entered by the user to an operation input unit (not shown).

[0054] <Example of operation> Next, an example of the operation of the plasma processing apparatus 1 of this embodiment 1 will be specifically described using Figures 5 and 6. Figure 5 is a diagram illustrating an example of the operation of the plasma processing apparatus 1. Figure 6 is a diagram illustrating another example of the operation of the plasma processing apparatus 1. Note that in Figures 5 and 6, the vacuum vessel 2, motor M1, motor M2, and control unit C are omitted from the illustration for the sake of simplicity.

[0055] In the plasma processing apparatus 1 of this embodiment 1, when the antenna 7 is not bent, the antenna 7 is in the state shown in Figure 5 relative to the high-frequency window 3. That is, the first connection angle θ1 and the second connection angle θ2 are each adjusted to their initial angles, for example, 90°. In this case, as shown in Figure 5, the antenna 7 faces the high-frequency window 3 in a straight shape without bending. Therefore, in the antenna section AP, for example, the separation distance L1 between the straight section 7a1 and the potential adjustment layer 6, the separation distance L2 between the straight section 7a2 and the potential adjustment layer 6, and the separation distance L3 between the straight section 7a3 and the potential adjustment layer 6 are all the same value, for example, 1.0 mm. Note that the antenna 7 used has a length of, for example, 1500 mm.

[0056] In other words, in antenna 7, the separation distance from the high-frequency window 3 is the same at one end, the center, and the other end, so plasma PD1 is generated as shown in Figure 5. In this case, the density of plasma PD1 is non-uniform along the longitudinal direction of antenna 7. Specifically, this non-uniformity is caused by the fact that the high-frequency power from antenna 7 is lower at one end and the other end compared to the center.

[0057] In contrast, in the plasma processing apparatus 1 of this embodiment 1, the control unit C controls motors M1 and M2 to rotate the rotating parts 8a1 and 8b1 relative to the main body 8a2 and 8b2, respectively, as shown in directions R1 and R2 in Figure 6. Furthermore, in this embodiment 1, as shown in Figure 6, the main body 8a2 and 8b2 also rotate as the rotating parts 8a1 and 8b1 rotate, causing the first conductor 9a and the second conductor 9b to bend and rotate as well. As a result, in the plasma processing apparatus 1 of this embodiment 1, the first connection angle θ1 and the second connection angle θ2 change to a smaller value (for example, 89°) from the initial angle.

[0058] As a result, in the plasma processing apparatus 1 of this embodiment 1, the antenna 7 faces the high-frequency window 3 in a bent state. Therefore, in the antenna section AP, as shown in Figure 7, the separation distance L4 between the potential adjustment layer 6 and the straight section 7a1 on the first capacitor section 8a side is, for example, 1.0 mm. Also, the separation distance L5 between the potential adjustment layer 6 and the straight section 7a1 on the bent section 7b1 side is, for example, 1.8 mm. In other words, in the straight section 7a1, which is one end of the antenna 7, the separation distance from the high-frequency window 3 increases as it approaches the bent section 7b1.

[0059] Furthermore, the separation distance L6 between the potential adjustment layer 6 and the straight section 7a2 on the bent section 7b1 side is, for example, 2.5 mm. Similarly, the separation distance L7 between the potential adjustment layer 6 and the straight section 7a2 on the bent section 7b2 side is, for example, 2.5 mm. In other words, at the central part of the antenna 7, the straight section 7a2 has the same separation distance from the high-frequency window 3, and faces the high-frequency window 3 in a linear form.

[0060] Furthermore, the separation distance L8 between the potential adjustment layer 6 and the straight section 7a3 on the bent section 7b2 side is, for example, 1.8 mm. Also, the separation distance L9 between the potential adjustment layer 6 and the straight section 7a3 on the second capacitor section 8b side is, for example, 1.0 mm. In other words, at the other end of the antenna 7, the separation distance from the high-frequency window 3 decreases as it approaches the second capacitor section 8b.

[0061] As a result of the above operation, in the plasma processing apparatus 1 of this embodiment 1, as shown in Figure 6, the central part of the antenna 7, which has a relatively large high-frequency power, is spaced further from the high-frequency window 3 than one end and the other end of the antenna 7. As a result, the density of the plasma PD2 can be made uniform along the longitudinal direction of the antenna 7. Specifically, in the plasma processing apparatus 1 of this embodiment, the difference in plasma density between the central part and the ends in the longitudinal direction of the antenna 7 can be adjusted. As a result, in this embodiment 1, a plasma processing apparatus 1 can be configured that can easily achieve uniform plasma density along the longitudinal direction of the antenna 7.

[0062] Furthermore, in the plasma processing apparatus 1 of this embodiment 1, the first capacitor section 8a and the second capacitor section 8b constitute the first connection section and the second connection section, respectively. As a result, in this embodiment 1, the potential rise due to the inductance component of the antenna 7 can be mitigated, and the plasma processing apparatus 1 can be easily made more compact.

[0063] <Variation> Here, another example of operation of the modified plasma processing apparatus 1 will be specifically explained using Figure 7. Figure 7 is a diagram illustrating an example of operation of the modified plasma processing apparatus 1. Note that in Figure 7, for the sake of simplifying the drawing, the vacuum vessel 2, motor M1, motor M2, and control unit C are not shown.

[0064] The main difference between this modified example and Embodiment 1 described above is that when the first connection angle θ1 and the second connection angle θ2 are changed using motors M1 and M2, only the rotating parts 8a1 and 8b1 are rotated, and the main body parts 8a2 and 8b2 are not rotated, and the first conductor 9a and the second conductor 9b are not bent.

[0065] <Example of operation> Specifically, in the description of Embodiment 1 above, the case was described in which the main body 8a2 and main body 8b2 of the first capacitor section 8a and the second capacitor section 8b rotate in conjunction with the rotation of the rotating section 8a1 and the rotating section 8b1, respectively. In other words, in Embodiment 1, as shown in Figure 6, when the rotating section 8a1 and the rotating section 8b1 rotate relative to the main body section 8a2 and the main body section 8b2, respectively, the first conductor 9a and the second conductor 9b also bend, thereby absorbing the change in the longitudinal dimension of the antenna 7.

[0066] On the other hand, in this modified example, the first conductor 9a and the second conductor 9b are configured not to bend. Therefore, in this modified example, when the control unit C controls motors M1 and M2 to rotate the rotating parts 8a1 and 8b1, as shown in Figure 7, the first conductor 9a and the second conductor 9b do not bend and do not rotate, and only the antenna 7 bends, generating a plasma PD2 with uniform density. In other words, in this modified example, when the rotating parts 8a1 and 8b1 rotate, the elastic deformation at the bent parts 7b1 and 7b2 absorbs the change in the longitudinal dimension of the antenna 7 solely by the antenna 7. Also, in this modified example, similar to Embodiment 1, the first connection angle θ1 and the second connection angle θ2 change from the initial angle (e.g., 90°) to a smaller value (e.g., 89°).

[0067] With the above configuration, the plasma processing apparatus 1 of this modified example achieves the same effects as that of Embodiment 1.

[0068] [Embodiment 2] Embodiment 2 of this disclosure will be described in detail with reference to Figure 8. Figure 8 is a diagram illustrating the main components of the plasma processing apparatus 1 according to Embodiment 2 of this disclosure. For the sake of convenience of explanation, components having the same function as those described in Embodiment 1 will be denoted by the same reference numerals, and their descriptions will not be repeated.

[0069] The main difference between this second embodiment and the first embodiment is that a cosine collector S1 and a spectrometer S2 are provided, and together with the control unit C, they constitute a spectral intensity distribution measuring instrument.

[0070] As shown in Figure 8, in the plasma processing apparatus 1 of this embodiment 2, for example, six cosine collectors S1 are provided on the side surface of the vacuum vessel 2 along the longitudinal direction of the antenna 7. The cosine collectors S1 are configured to collect light from the plasma PD2 inside the vacuum vessel 2 and output the detected light to the spectrometer S2 via an optical fiber. Note that the cosine collectors S1 are just one example of a component for focusing plasma light emission into an optical fiber, and other focusing components may be used.

[0071] The spectrometer S2 acquires the wavelength spectrum of the light received by the cosine collector S1 and outputs it to the control unit C. Based on the required spectral intensity (the intensity of the required wavelength band in the wavelength spectrum), the control unit C acquires the emission intensity of the plasma PD2 generated inside the vacuum vessel 2 along the longitudinal direction.

[0072] Furthermore, the control unit C also functions as an optical emission spectrometer and is configured to perform a predetermined spectroscopic analysis on the light detected by the cosine collector S1. This allows the control unit C to detect the elements and their concentrations contained in the plasma PD2 generated inside the vacuum vessel 2, based on the spectroscopic analysis results. Moreover, based on these detection results, the control unit C can easily determine the cause of plasma generation. In addition, even if an abnormal discharge occurs inside the vacuum vessel 2, the control unit C can also detect the elements and their concentrations contained in the light of the abnormal discharge, based on the spectroscopic analysis results.

[0073] With the above configuration, the plasma processing apparatus 1 of this second embodiment can acquire the emission intensity of the plasma PD2 generated inside the vacuum vessel 2 along the longitudinal direction of the antenna 7. As a result, in the plasma processing apparatus 1 of this second embodiment, the control unit C can control motors M1 and M2 based on the acquired emission intensity, and can more appropriately adjust the first connection angle θ1 and the second connection angle θ2 to more easily achieve uniformity of plasma density along the longitudinal direction of the antenna 7.

[0074] [Embodiment 3] Embodiment 3 of this disclosure will be described in detail with reference to Figure 9. Figure 9 is a diagram illustrating the main components of the plasma processing apparatus 1 according to Embodiment 3 of this disclosure. For the sake of convenience of explanation, components having the same function as those described in Embodiment 2 above will be denoted by the same reference numerals, and their descriptions will not be repeated.

[0075] The main difference between this second embodiment and the second embodiment described above is the addition of a film thickness measuring instrument S3.

[0076] As shown in Figure 8, in the plasma processing apparatus 1 of this embodiment 3, for example, three film thickness measuring instruments S3 are provided on the upper surface of the vacuum vessel 2 along the longitudinal direction of the antenna 7. The film thickness measuring instruments S3 are configured using ellipsometers or the like, and detect the film thickness of the film deposited on the workpiece H1. The film thickness measuring instruments S3 then output the measurement result to the control unit C.

[0077] With the above configuration, the plasma processing apparatus 1 of this third embodiment achieves the same effects as that of the first embodiment.

[0078] Furthermore, in the plasma processing apparatus 1 of this embodiment 3, multiple film thickness measuring instruments S3 are arranged along the longitudinal direction of the antenna 7. As a result, in the plasma processing apparatus 1 of this embodiment 3, the control unit C can use the measurement results of the film thickness of the film deposited on the workpiece H1 along the longitudinal direction of the antenna 7 to obtain the film thickness along the longitudinal direction of the antenna 7. As a result, in the plasma processing apparatus 1 of this embodiment 3, the control unit C can adjust the high-frequency power of the antenna 7 based on the obtained film thickness. Therefore, the density of the plasma PD2 contributing to the film deposition on the workpiece H1 can be appropriately changed, and the distribution of film thickness along the longitudinal direction of the antenna 7 can be made uniform, enabling high-precision film deposition on the workpiece H1.

[0079] In the above description, the case in which motor M1 and motor M2 are used in the first drive unit and the second drive unit, respectively, has been described, but this disclosure is not limited thereto. For example, a configuration in which a rotating rod is attached to the rotating unit 8a1 and the rotating unit 8b1, and the first connection angle θ1 and the second connection angle θ2 are changed by the user operating the rotating rod.

[0080] However, as described above, it is preferable to use motor M1 and motor M2 respectively in the first and second drive units, as this allows for precise changes to at least one of the first connection angle θ1 or the second connection angle θ2, and thus enables high-precision uniformity of plasma density.

[0081] In addition to the above explanation, a configuration in which only the first connection angle θ1 or the second connection angle θ2 is changed is also acceptable.

[0082] 〔summary〕 To solve the above problems, a plasma processing apparatus according to a first aspect of the present disclosure comprises a vacuum vessel for housing an object to be processed, a high-frequency window for introducing a high-frequency magnetic field for generating plasma into the vacuum vessel, and an antenna section, wherein the antenna section comprises a bar-shaped antenna for generating the high-frequency magnetic field, a pair of conductors, a first conductor and a second conductor, for supplying a high-frequency current to the antenna, a member for connecting one end of the antenna to the first conductor, a first connection section that can change the connection angle between the antenna and the first conductor, and a member for connecting the other end of the antenna to the second conductor, a second connection section that can change the connection angle between the antenna and the second conductor, wherein the antenna can be bent in accordance with a change in at least one of the first connection angle or the second connection angle.

[0083] According to the above configuration, it is possible to provide a plasma processing apparatus that can easily achieve uniformity of plasma density in the longitudinal direction of the antenna.

[0084] A plasma processing apparatus in a second embodiment may be configured such that, in the plasma processing apparatus of the first embodiment, the first connection portion has a first conductor-side electrode connected to the first conductor and a first antenna electrode connected to one end of the antenna, and the first conductor-side electrode and the first antenna electrode are rotatable relative to each other with a gap between them, forming a first capacitor portion; and the second connection portion has a second conductor-side electrode connected to the second conductor and a second antenna electrode connected to the other end of the antenna, and the second conductor-side electrode and the second antenna electrode are rotatable relative to each other with a gap between them, forming a second capacitor portion.

[0085] According to the above configuration, the potentials at the first and second connection points can be reduced, making it easy to miniaturize the plasma processing apparatus.

[0086] A plasma processing apparatus of the third embodiment may further include, in the plasma processing apparatus of the first or second embodiment, the antenna section comprising a first drive unit for changing the first connection angle and a second drive unit for changing the second connection angle, and a control unit for controlling the first drive unit and the second drive unit.

[0087] According to the above configuration, at least one of the first connection angle or the second connection angle can be changed with high precision, and the uniformity of the plasma density can be achieved with high precision.

[0088] The plasma processing apparatus of the fourth embodiment may further include a spectral intensity distribution measuring instrument that measures the distribution of the spectral intensity of light emitted by the plasma along the longitudinal direction of the antenna, as in the plasma processing apparatus of any of the first to third embodiments.

[0089] With the above configuration, the spectral intensity distribution analyzer can be used to obtain the emission intensity of the plasma generated inside the vacuum vessel along the longitudinal direction.

[0090] The plasma processing apparatus of the fifth embodiment may further include a film thickness measuring instrument for measuring the film thickness of a film formed on the workpiece along the longitudinal direction of the antenna, as in the plasma processing apparatus of any of the first to fourth embodiments.

[0091] With the above configuration, by using the measurement results of the film thickness measuring instrument, the film deposition process on the workpiece can be performed with high precision.

[0092] The plasma processing apparatus of the sixth embodiment is a plasma processing apparatus of any of the first to fourth embodiments, in which the antenna may have at least two linear portions and a bendable portion provided between the two linear portions.

[0093] According to the above configuration, the distance between the antenna and the high-frequency window can be partially and reliably changed, and the uniformity of the plasma density along the longitudinal direction of the antenna can be reliably achieved.

[0094] This disclosure is not limited to the embodiments described above, and various modifications are possible within the scope of the claims. Embodiments obtained by appropriately combining the technical means disclosed in each embodiment are also included in the technical scope of this disclosure. [Explanation of Symbols]

[0095] 1. Plasma processing equipment 2 Vacuum container 3 High-frequency window 7 Antennas 8a First capacitor section (first connection section) 8b Second capacitor section (second connection section) 9a First conductor (a pair of conductors) 9b Second conductor (a pair of conductors) C1 First antenna electrode, second antenna electrode C2 First conductor side electrode, second conductor side electrode θ1 First connection angle θ2 Second connection angle S1 Cosine Collector (Spectroscopic Intensity Distribution Analyzer) S2 spectrometer (spectral intensity distribution measuring device) S3 Film Thickness Gauge C control section M1, M2 motors W Cooling water (cooling medium, dielectric layer)

Claims

1. A vacuum container that houses the object to be processed, A high-frequency window is used to introduce a high-frequency magnetic field that generates plasma inside the vacuum container into the vacuum container, It includes an antenna section, The aforementioned antenna section is The bar-shaped antenna that generates the aforementioned high-frequency magnetic field, A first conductor and a second conductor are a pair of conductors for supplying high-frequency current to the antenna, A member for connecting one end of the antenna and the first conductor, comprising a first connecting portion that can change the first connection angle, which is the connection angle between the antenna and the first conductor, A member for connecting the other end of the antenna and the second conductor, comprising a second connecting portion capable of changing the second connection angle, which is the connection angle between the antenna and the second conductor, The plasma processing apparatus comprises an antenna that can be bent in response to a change in at least one of the first connection angle or the second connection angle.

2. The first connection portion comprises a first conductor-side electrode connected to the first conductor and a first antenna electrode connected to one end of the antenna, and the first conductor-side electrode and the first antenna electrode are rotatable relative to each other across a gap, thus constituting a first capacitor portion. The plasma processing apparatus according to claim 1, wherein the second connection portion comprises a second conductor side electrode connected to the second conductor and a second antenna electrode connected to the other end of the antenna, and the second conductor side electrode and the second antenna electrode are rotatable relative to each other with a gap between them, forming a second capacitor portion.

3. The antenna unit comprises a first drive unit for changing the first connection angle and a second drive unit for changing the second connection angle. The plasma processing apparatus according to claim 1, further comprising a control unit for controlling the first drive unit and the second drive unit.

4. The plasma processing apparatus according to claim 1, further comprising a spectral intensity distribution measuring instrument for measuring the distribution of the spectral intensity of light emitted by the plasma along the longitudinal direction of the antenna.

5. The plasma processing apparatus according to claim 1, further comprising a film thickness measuring instrument for measuring the film thickness of a film formed on the workpiece along the longitudinal direction of the antenna.

6. The plasma processing apparatus according to any one of claims 1 to 5, wherein the antenna has at least two linear portions and a bendable portion provided between the two linear portions.

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