JP2024059570A - Substrate processing apparatus and shutter - Google Patents

Abstract

[Problem] To provide a substrate processing apparatus and shutter capable of suppressing plasma leakage. [Solution] The substrate processing apparatus has a chamber, a substrate support part disposed within the chamber, a valve body for opening and closing the opening of the cylindrical chamber, a shutter disposed between the inner periphery of the chamber and the substrate support part and including a baffle plate having a vertically gradient shape formed on the end on the substrate support part side, and a contact member disposed on the side of the substrate support part and formed of a conductive elastic member, and when the shutter is in a closed state, contact is maintained between the end on the substrate support part side and the contact member. [Selected Figure] Figure 4

Description

This disclosure relates to a substrate processing apparatus and a shutter.

Conventionally, plasma processing apparatuses are known that perform desired plasma processing on wafers, which are substrates to be processed for semiconductor devices. The plasma processing apparatus includes, for example, a chamber that houses a wafer, and in the chamber, a mounting table on which the wafer is placed and which functions as a lower electrode, and an upper electrode facing the mounting table are arranged. The wafer is carried into or out of the chamber, for example, by a transport robot through an opening provided in the chamber. In addition, in order to transport parts in the chamber that exceed the outer diameter of the wafer through the opening of the chamber, for example, a shutter mechanism has been proposed that enlarges the opening of the chamber and has a valve body that runs along the entire inner circumference of the chamber (Patent Document 1).

JP 2021-22652 A

The present disclosure provides a substrate processing apparatus and shutter that can suppress plasma leakage.

A substrate processing apparatus according to one aspect of the present disclosure includes a chamber, a substrate support disposed within the chamber, a valve body for opening and closing the opening of the cylindrical chamber, a shutter disposed between the inner circumference of the chamber and the substrate support and including a baffle plate having a vertically gradient shape formed at the end on the substrate support side, and a contact member formed of a conductive elastic member and provided on the side of the substrate support, and when the shutter is closed, contact is maintained between the end on the substrate support side and the contact member.

This disclosure makes it possible to suppress plasma leakage.

FIG. 1 is a diagram illustrating an example of a plasma processing system according to a first embodiment of the present disclosure. FIG. 2 is a perspective view showing an example of a shutter in the first embodiment. FIG. 3 is a partial enlarged view showing an example of a cross section of the shutter in the first embodiment. FIG. 4 is a partial enlarged view showing an example of a cross section in a state where the shutter is closed in the first embodiment. FIG. 5 is a perspective view illustrating an example of a contact member in the first embodiment. FIG. 6 is a diagram showing an example of a cross section of the first embodiment when the shutter is closed. FIG. 7 is a diagram showing an example of a cross section of the second embodiment when the shutter is closed. FIG. 8 is a diagram showing an example of a cross section of the third embodiment when the shutter is closed. FIG. 9 is a diagram showing an example of an experimental result of plasma leakage. FIG. 10 is a diagram showing an example of a variation of the contact member. FIG. 11 is a partial enlarged view showing an example of a cross section near a contact member in the second embodiment. FIG. 12 is a diagram showing an example of a core material of the contact member according to the second embodiment. FIG. 13 is a perspective view illustrating an example of a contact member according to the second embodiment. FIG. 14 is a diagram showing another example of the core material of the contact member in the second embodiment. FIG. 15 is a diagram showing another example of the core material of the contact member in the second embodiment. FIG. 16 is a diagram showing another example of the core material of the contact member in the second embodiment.

Below, embodiments of the disclosed substrate processing apparatus and shutter are described in detail with reference to the drawings. Note that the disclosed technology is not limited to the following embodiments.

A baffle plate is placed inside the chamber to prevent the plasma generated inside the chamber from leaking into the exhaust system. When the shutter valve body is closed, the upper part of the valve body is in contact with the upper surface of the chamber, and the lower part of the valve body is in contact with the baffle plate, the deposit shield, etc. In other words, the valve body is electrically connected (conductive) with the upper surface of the chamber and the baffle plate, etc. However, when the valve body expands due to heat input from plasma processing, although the upper part of the valve body is in contact with the upper surface of the chamber, the lower part of the valve body may separate from the baffle plate, the deposit shield, etc., resulting in a plasma leak. Therefore, it is expected that the electrical connection will not be broken even if the valve body expands, thereby suppressing the plasma leak.

First Embodiment
[Configuration of Plasma Processing System]
An example of the configuration of a plasma processing system will be described below. FIG. 1 is a diagram showing an example of a plasma processing system according to a first embodiment of the present disclosure. As shown in FIG. 1, the plasma processing system includes a capacitively coupled plasma processing apparatus 1 and a control unit 2. The capacitively coupled plasma processing apparatus 1 includes a plasma processing chamber 10, a gas supply unit 20, a power supply 30, and an exhaust system 40. The plasma processing apparatus 1 also includes a substrate support unit 11 and a gas introduction unit. The gas introduction unit is configured to introduce at least one processing gas into the plasma processing chamber 10. The gas introduction unit includes a shower head 13. The substrate support unit 11 is disposed in the plasma processing chamber 10. The shower head 13 is disposed above the substrate support unit 11. In one embodiment, the shower head 13 constitutes at least a part of the ceiling of the plasma processing chamber 10. The plasma processing chamber 10 has a plasma processing space 10s defined by the shower head 13, a sidewall 10a of the plasma processing chamber 10, and the substrate support unit 11. The plasma processing chamber 10 has at least one gas supply port for supplying at least one processing gas to the plasma processing space 10s and at least one gas exhaust port for exhausting gas from the plasma processing space 10s. The plasma processing chamber 10 is grounded. The showerhead 13 and the substrate support 11 are electrically insulated from the housing of the plasma processing chamber 10.

The substrate support 11 includes a main body 111 and a ring assembly 112. The main body 111 has a central region 111a for supporting the substrate W and an annular region 111b for supporting the ring assembly 112. A wafer is an example of a substrate W. The annular region 111b of the main body 111 surrounds the central region 111a of the main body 111 in a plan view. The substrate W is disposed on the central region 111a of the main body 111, and the ring assembly 112 is disposed on the annular region 111b of the main body 111 so as to surround the substrate W on the central region 111a of the main body 111. Therefore, the central region 111a is also called a substrate support surface for supporting the substrate W, and the annular region 111b is also called a ring support surface for supporting the ring assembly 112.

In one embodiment, the main body 111 includes a base 1110 and an electrostatic chuck 1111. The base 1110 includes a conductive member. The conductive member of the base 1110 may function as a lower electrode. The electrostatic chuck 1111 is disposed on the base 1110. The electrostatic chuck 1111 includes a ceramic member 1111a and an electrostatic electrode 1111b disposed within the ceramic member 1111a. The ceramic member 1111a has a central region 111a. In one embodiment, the ceramic member 1111a also has an annular region 111b. Note that other members surrounding the electrostatic chuck 1111, such as an annular electrostatic chuck or an annular insulating member, may have the annular region 111b. In this case, the ring assembly 112 may be disposed on the annular electrostatic chuck or the annular insulating member, or may be disposed on both the electrostatic chuck 1111 and the annular insulating member. At least one RF/DC electrode coupled to an RF (Radio Frequency) power source 31 and/or a DC (Direct Current) power source 32, which will be described later, may be disposed within the ceramic member 1111a. In this case, the at least one RF/DC electrode functions as a lower electrode. When a bias RF signal and/or a DC signal, which will be described later, is supplied to the at least one RF/DC electrode, the RF/DC electrode is also called a bias electrode. Note that the conductive member of the base 1110 and the at least one RF/DC electrode may function as multiple lower electrodes. Also, the electrostatic electrode 1111b may function as the lower electrode. Thus, the substrate support 11 includes at least one lower electrode.

The ring assembly 112 includes one or more annular members. In one embodiment, the one or more annular members include one or more edge rings and at least one cover ring. The edge rings are formed of a conductive or insulating material, and the cover rings are formed of an insulating material.

The substrate support 11 may also include a temperature adjustment module configured to adjust at least one of the electrostatic chuck 1111, the ring assembly 112, and the substrate to a target temperature. The temperature adjustment module may include a heater, a heat transfer medium, a flow passage 1110a, or a combination thereof. A heat transfer fluid such as brine or a gas flows through the flow passage 1110a. In one embodiment, the flow passage 1110a is formed in the base 1110, and one or more heaters are disposed in the ceramic member 1111a of the electrostatic chuck 1111. The substrate support 11 may also include a heat transfer gas supply configured to supply a heat transfer gas to a gap between the back surface of the substrate W and the central region 111a.

The shower head 13 is configured to introduce at least one processing gas from the gas supply unit 20 into the plasma processing space 10s. The shower head 13 has at least one gas supply port 13a, at least one gas diffusion chamber 13b, and multiple gas inlets 13c. The processing gas supplied to the gas supply port 13a passes through the gas diffusion chamber 13b and is introduced into the plasma processing space 10s from the multiple gas inlets 13c. The shower head 13 also includes at least one upper electrode. In addition to the shower head 13, the gas introduction unit may include one or more side gas injectors (SGIs) attached to one or more openings formed in the sidewall 10a.

The gas supply 20 may include at least one gas source 21 and at least one flow controller 22. In one embodiment, the gas supply 20 is configured to supply at least one process gas from a respective gas source 21 through a respective flow controller 22 to the showerhead 13. Each flow controller 22 may include, for example, a mass flow controller or a pressure-controlled flow controller. Additionally, the gas supply 20 may include one or more flow modulation devices to modulate or pulse the flow rate of the at least one process gas.

The power source 30 includes an RF power source 31 coupled to the plasma processing chamber 10 via at least one impedance matching circuit. The RF power source 31 is configured to supply at least one RF signal (RF power) to at least one lower electrode and/or at least one upper electrode. This causes a plasma to be formed from at least one processing gas supplied to the plasma processing space 10s. Thus, the RF power source 31 can function as at least a part of a plasma generating unit configured to generate plasma from one or more processing gases in the plasma processing chamber 10. In addition, by supplying a bias RF signal to at least one lower electrode, a bias potential is generated on the substrate W, and ion components in the formed plasma can be attracted to the substrate W.

In one embodiment, the RF power supply 31 includes a first RF generating section 31a and a second RF generating section 31b. The first RF generating section 31a is coupled to at least one lower electrode and/or at least one upper electrode via at least one impedance matching circuit and configured to generate a source RF signal (source RF power) for plasma generation. In one embodiment, the source RF signal has a frequency in the range of 10 MHz to 150 MHz. In one embodiment, the first RF generating section 31a may be configured to generate multiple source RF signals having different frequencies. The generated one or more source RF signals are supplied to at least one lower electrode and/or at least one upper electrode.

The second RF generator 31b is coupled to at least one lower electrode via at least one impedance matching circuit and configured to generate a bias RF signal (bias RF power). The frequency of the bias RF signal may be the same as or different from the frequency of the source RF signal. In one embodiment, the bias RF signal has a lower frequency than the frequency of the source RF signal. In one embodiment, the bias RF signal has a frequency in the range of 100 kHz to 60 MHz. In one embodiment, the second RF generator 31b may be configured to generate multiple bias RF signals having different frequencies. The generated one or more bias RF signals are provided to at least one lower electrode. Also, in various embodiments, at least one of the source RF signal and the bias RF signal may be pulsed.

The power supply 30 may also include a DC power supply 32 coupled to the plasma processing chamber 10. The DC power supply 32 includes a first DC generator 32a and a second DC generator 32b. In one embodiment, the first DC generator 32a is connected to at least one lower electrode and configured to generate a first DC signal. The generated first bias DC signal is applied to the at least one lower electrode. In one embodiment, the second DC generator 32b is connected to at least one upper electrode and configured to generate a second DC signal. The generated second DC signal is applied to the at least one upper electrode.

In various embodiments, at least one of the first and second DC signals may be pulsed. In this case, a sequence of voltage pulses is applied to at least one lower electrode and/or at least one upper electrode. The voltage pulses may have a rectangular, trapezoidal, triangular, or combination thereof pulse waveform. In one embodiment, a waveform generator for generating a sequence of voltage pulses from the DC signal is connected between the first DC generator 32a and at least one lower electrode. Thus, the first DC generator 32a and the waveform generator constitute a voltage pulse generator. When the second DC generator 32b and the waveform generator constitute a voltage pulse generator, the voltage pulse generator is connected to at least one upper electrode. The voltage pulses may have a positive polarity or a negative polarity. Also, the sequence of voltage pulses may include one or more positive polarity voltage pulses and one or more negative polarity voltage pulses within one period. The first and second DC generating units 32a and 32b may be provided in addition to the RF power source 31, or the first DC generating unit 32a may be provided in place of the second RF generating unit 31b.

The exhaust system 40 may be connected to, for example, a gas exhaust port 10e provided at the bottom of the plasma processing chamber 10. The exhaust system 40 may include a pressure regulating valve and a vacuum pump. The pressure in the plasma processing space 10s is adjusted by the pressure regulating valve. The vacuum pump may include a turbomolecular pump, a dry pump, or a combination thereof.

An opening 50 for loading and unloading the substrate W is provided on the side wall 10a of the plasma processing chamber 10, and a gate valve 51 for opening and closing the opening 50 is arranged. In the plasma processing chamber 10, a deposit shield 52 is detachably provided along the inner wall of the plasma processing chamber 10. An annular insulating member 54 made of, for example, alumina (Al2O3) or yttria (Y2O3) is airtightly arranged on the upper part of the deposit shield 52. The deposit shield 52 is provided above the opening 50 of the plasma processing chamber 10. The lower part of the deposit shield 52 closes the opening 50 by contacting the upper part of the valve body 61 of the shutter 60 described later. The deposit shield 52 can be formed, for example, by coating an aluminum material with ceramics such as Y2O3. The lower part of the deposit shield 52 is coated with a conductive material, such as stainless steel or a nickel alloy, so as to be conductive with the valve body 61 that it contacts. The deposit shield 52 is an example of a conductive upper member. The insulating member 54 is a member that insulates between the shower head 13 and the deposit shield 52. In other words, the insulating member 54 is a member that insulates between the shower head 13 and the side wall 10a, the deposit shield 52, and the valve body 61, which are conductive with each other when the shutter 60 is closed. In addition, the lower part of the shutter 60 has an end 75 on the substrate support part 11 side of the baffle plate 70 described later, which is in slidable contact with the side wall of the main body part 111.

The substrate W is loaded and unloaded by opening and closing the gate valve 51. However, since the gate valve 51 is disposed outside (on the transfer chamber side) of the plasma processing chamber 10, a space is formed in which the opening 50 protrudes toward the transfer chamber side. Therefore, the plasma generated in the plasma processing chamber 10 diffuses to that space, causing deterioration in plasma uniformity and deterioration of the seal member of the gate valve 51. Similarly, the plasma generated in the plasma processing chamber 10 diffuses to the space on the gas exhaust port 10e side, causing deterioration in plasma uniformity. Therefore, the shutter 60 blocks the space between the deposit shield 52 and the side wall of the main body 111, thereby blocking the opening 50 and gas exhaust port 10e of the plasma processing chamber 10 from the plasma processing space 10s. In addition, the lifting mechanism 53 that drives the shutter 60 is disposed, for example, below the valve body 61. The lifting mechanism 53 has, for example, a rod connected to the valve body 61 and a drive unit that raises and lowers the rod up and down using an air cylinder, a motor, or the like. The shutter 60 is driven up and down by the lifting mechanism 53 to open and close the opening 50. It is preferable to install multiple lifting mechanisms 53, for example, three. The shutter 60 may include the lifting mechanism 53.

The control unit 2 processes computer-executable instructions that cause the plasma processing apparatus 1 to execute various steps described in this disclosure. The control unit 2 may be configured to control each element of the plasma processing apparatus 1 to execute various steps described herein. In one embodiment, a part or all of the control unit 2 may be included in the plasma processing apparatus 1. The control unit 2 may include a processing unit 2a1, a storage unit 2a2, and a communication interface 2a3. The control unit 2 is realized, for example, by a computer 2a. The processing unit 2a1 may be configured to perform various control operations by reading a program from the storage unit 2a2 and executing the read program. This program may be stored in the storage unit 2a2 in advance, or may be acquired via a medium when necessary. The acquired program is stored in the storage unit 2a2 and is read from the storage unit 2a2 by the processing unit 2a1 and executed. The medium may be various storage media readable by the computer 2a, or may be a communication line connected to the communication interface 2a3. The processing unit 2a1 may be a CPU (Central Processing Unit). The storage unit 2a2 may include a RAM (Random Access Memory), a ROM (Read Only Memory), a HDD (Hard Disk Drive), a SSD (Solid State Drive), or a combination of these. The communication interface 2a3 may communicate with the plasma processing apparatus 1 via a communication line such as a LAN (Local Area Network).

[Details of the shutter 60]
FIG. 2 is a perspective view showing an example of a shutter in the first embodiment. FIG. 3 is a partially enlarged view showing an example of a cross section of the shutter in the first embodiment. As shown in FIGS. 2 and 3, the shutter 60 has a valve body 61 and a baffle plate 70. The valve body 61 is a cylindrical valve body along the inner circumference of the plasma processing chamber 10. The valve body 61 has an upper part 62 that abuts against the deposit shield 52 when the opening 50 is closed, and a bottom part 63 that is connected to the baffle plate 70. In addition, a conductive member 64 for ensuring conduction with the deposit shield 52 is provided on the upper part 62. The conductive member 64 is also called a conductance band or spiral, and is a conductive elastic member. For example, stainless steel, nickel alloy, etc. can be used as the conductive member 64. For example, the conductive member 64 is formed by winding a band-shaped member in a spiral shape. For example, the conductive member 64 may be an obliquely wound coil spring with a U-shaped jacket.

The baffle plate 70 has a flat portion 71, a wall portion 72, and a flange portion 73. The flat portion 71 is an annular plate having a predetermined width that contacts the side wall of the main body portion 111 via a contact member 116 described later. The width of the flat portion 71 is an example of a first width. The flat portion 71 is provided with a through hole (not shown) to enable exhaust from the plasma processing space 10s. The wall portion 72 is provided in a cylindrical shape as a vertical surface (wall) on the outer periphery of the flat portion 71, and the upper portion is connected to the flange portion 73. The flange portion 73 is provided in an annular shape on the upper portion of the wall portion 72 and is connected to the valve body 61. In other words, the flange portion 73 has a flat surface in an annular shape having a width that allows the valve body 61 to be placed thereon. The width of the upper surface (flat surface) of the flange portion 73 is an example of a second width. That is, the valve body 61 and the baffle plate 70 together form the shutter 60, and when the shutter 60 opens and closes, the baffle plate 70 moves up and down together with the valve body 61.

The upper surface 73a of the flange portion 73 contacts the lower surface 63a of the bottom portion 63 of the valve body 61. Between the upper surface 73a and the lower surface 63a, a conductive member 74 is provided to ensure electrical continuity between the valve body 61 and the baffle plate 70. The conductive member 74 is a conductive elastic member similar to the conductive member 64. In addition, a vertical gradient shape 76 is formed on the inner periphery side of the flat portion 71, i.e., the end portion 75 on the substrate support portion 11 side, which is provided on the side wall of the main body portion 111, and contacts a contact member 116 (described later). The connection portion between the upper portion of the gradient shape 76 and the upper surface of the flat portion 71 is formed by a curved surface so as not to have any sharp edges.

Next, the state of contact between the shutter 60 and the sidewall of the main body 111 when the shutter is closed will be described with reference to FIG. 4. FIG. 4 is a partially enlarged view showing an example of a cross section of the shutter in the closed state in the first embodiment. As shown in FIG. 4, the valve body 61 of the shutter 60 has its upper portion 62 abutted against the deposit shield 52 provided near the shower head 13 at the top of the plasma processing chamber 10, and the conductive member 64 is in a crushed state. At this time, electrical continuity is ensured between the valve body 61 and the deposit shield 52.

A ring-shaped shield member 115 is provided on the side wall of the main body 111. The upper part of the shield member 115 may be provided up to just below the ring assembly 112. The shield member 115 is a member that protects the lower part of the substrate support part 11, such as the main body 111, from plasma. A sprayed film of Y2O3 or the like is formed on the surface of the shield member 115. A circumferential groove 115a is formed in the shield member 115 for providing the contact member 116. The bottom of the groove 115a (the side of the main body 111) is not sprayed with a film, and electrical continuity is ensured by the contact between the shield member 115 and the contact member 116.

The contact member 116 is provided in the groove 115a and is made of a conductive elastic member. The contact member 116 has a spring portion 117 that abuts against the sloped shape 76 of the end portion 75 of the baffle plate 70. In other words, the contact member 116 is a member that ensures electrical continuity between the shield member 115 and the baffle plate 70. The end portion 75 is also formed so that its vertical length is longer than the vertical length of the contact member 116. In this way, when the shutter 60 is closed, electrical continuity is ensured between the deposit shield 52, the valve body 61, the baffle plate 70, the contact member 116, and the shield member 115.

Figure 5 is a perspective view showing an example of a contact member in the first embodiment. As shown in Figure 5, the contact member 116 is formed by connecting multiple spring portions 117 in the circumferential direction. When the shutter 60 is closed, the spring portions 117 are pushed into the groove 115a along the sloped shape 76 of the end portion 75. In other words, when the shutter 60 is closed, contact is maintained between the end portion 75 of the baffle plate 70 on the substrate support portion 11 side and the contact member 116.

[Reference Example]
Next, reference examples 1 to 3 will be described with reference to FIG. 6 to FIG. 8. FIG. 6 is a diagram showing an example of a cross section of the shutter of reference example 1 in a closed state. In addition, in FIG. 6 to FIG. 8, some details of each part are omitted. The shutter 200 shown in FIG. 6 has a valve body 201 and a baffle plate 202. In addition, a ring-shaped shield member 210 is provided on the side wall of the main body part 111. In reference example 1, the shutter 200 is in a closed state, and the upper part of the valve body 201 is in contact with the deposit shield 52 provided near the shower head 13 at the upper part of the plasma processing chamber 10. On the other hand, the end part 203 of the baffle plate 202 on the main body part 111 side is in a state where a gap 204 is opened between the end part 203 and the shield member 210. In other words, in reference example 1, the baffle plate 202, which was conventionally fixed to the shield member 210, is made movable up and down together with the valve body 201. In this case, the baffle plate 202 and the shield member 210 are not electrically connected to each other, causing a plasma leak.

7 is a diagram showing an example of a cross section of the shutter of Reference Example 2 in a closed state. The shutter 220 shown in FIG. 7 has a valve body 221 and a baffle plate 222. In addition, a ring-shaped shield member 210 is provided on the side wall of the main body 111, as in Reference Example 1. In Reference Example 2, the shutter 220 is in a closed state, and the upper part of the valve body 221 is in contact with the deposit shield 52 provided near the shower head 13 at the upper part of the plasma processing chamber 10. On the other hand, a conductive member 224 is provided on the side of the end 223 of the baffle plate 222 on the main body 111 side, and is in contact with the shield member 210. In other words, Reference Example 2 ensures conduction between the baffle plate 202 and the shield member 210 of Reference Example 1 by the conductive member 224. The conductive member 224 is a conductive elastic member similar to the conductive member 64 described above. In this case, a repulsive force against the crushing force is generated in the conductive member 224, so that radial stress is applied to the baffle plate 222, which may distort and damage the baffle plate 222. Also, when the shutter 220 is driven, the conductive member 224 slides up and down while in contact with the shield member 210, which may damage the conductive member 224. Even if the conductive member 224 is provided on the shield member 210 side, for example, when the shutter 220 is driven, the end portion 223 moves parallel to the wall surface of the shield member 210, so that a force that is not crushing the conductive member 224 is applied, which may damage the conductive member 224.

Figure 8 is a diagram showing an example of a cross section of the shutter of Reference Example 3 in a closed state. The shutter 230 shown in Figure 8 has a valve body 231 and a baffle plate 232. In addition, a ring-shaped shield member 211 is provided on the side wall of the main body 111. A flange portion 212 is provided on the shield member 211 so as to contact the upper surface of the end 233 of the baffle plate 232. In Reference Example 3, the shutter 230 is in a closed state, and the upper portion of the valve body 231 is in contact with the deposit shield 52 provided near the shower head 13 at the upper portion of the plasma processing chamber 10. Meanwhile, a conductive member 234 is provided on the upper surface of the end 233 of the baffle plate 232 on the main body 111 side. The conductive member 234 is crushed by the shutter 230 closing, ensuring conduction between the flange portion 212 and the end 233. The conductive member 234 is a conductive elastic member similar to the conductive member 64 described above. In other words, in Reference Example 3, the direction of contact between the baffle plate and the shielding member is changed compared to Reference Example 2. In this case, the contact between the baffle plate 232 and the shielding member 211 is in the vertical direction, so that when the shutter 230 is driven, a vertical stress is applied to the baffle plate 232, which may distort and damage the baffle plate 232. In addition, if the shutter 230 expands due to heat input from the plasma, the flange portion 212 and the end portion 233 may separate, and electrical continuity may not be ensured.

[Experimental result]
Next, the experimental results of plasma leakage will be described with reference to FIG. 9. FIG. 9 is a diagram showing an example of the experimental results of plasma leakage. Table 90 shown in FIG. 9 shows the presence or absence of plasma leakage light emission when plasma processing is performed under conditions 1 to 4 for Reference Example 4, Reference Example 1, and an example according to this embodiment. The light emission is based on an image taken from a viewing window near the gas exhaust port 10e of the plasma processing chamber 10. Here, Reference Example 4 is a case of a conventional plasma processing apparatus in which a baffle plate is fixed to a shielding member, a part of the side wall of the plasma processing chamber is opened, and a shutter is provided to open and close the opening. Reference Example 1 is a case of a plasma processing apparatus using the shutter 200 shown in FIG. 6. Condition 1 is a case in which 2 kW is supplied as a source RF signal and 0 kV is supplied as a bias DC signal. Condition 2 is a case in which 2 kW is supplied as a source RF signal and 4 kV is supplied as a bias DC signal. Condition 3 is a case in which 0 kW is supplied as a source RF signal and 5 kV is supplied as a bias DC signal. Condition 4 is a case where 0 kW is supplied as a source RF signal and 6 kV is supplied as a bias DC signal.

Under conditions 1 to 3, in Reference Example 4 and the working example, no light emission was observed (no light emission) and no plasma leak occurred. In contrast, in Reference Example 1, light emission was observed (light emission occurred) and plasma leak occurred. Under condition 4, in the working example, no light emission was observed (no light emission) and no plasma leak occurred. In contrast, in Reference Example 4 and Reference Example 1, light emission was observed (light emission occurred) and plasma leak occurred. In other words, with the shutter 60 of this embodiment, plasma leak can be suppressed more than with the shutter in the conventional plasma processing apparatus of Reference Example 4.

As described above, in the embodiment according to this embodiment, even if the valve body 61 or the baffle plate 70 expands due to heat input from plasma processing, the electrical connection between the end portion 75 and the contact member 116 is not broken, and plasma leakage can be suppressed. Furthermore, thermal expansion in the horizontal direction can also be absorbed by the spring portion 117, so that the thermal stress acting on the shutter 60 can be alleviated. Furthermore, contact stress in the driving direction of the shutter 60 can also be alleviated in a similar manner.

[Contact material variations]
Next, variations of the contact member 116 will be described with reference to Fig. 10. Fig. 10 is a diagram showing an example of a variation of the contact member. As shown in Fig. 10, the contact member 116 is the contact member 116 in the above-described embodiment, and is a representative representation of one spring portion 117. The example in Fig. 10 shows a cross section of the contact member 116.

The contact member 116a is a variation of the contact member with a circular spring portion. The example in FIG. 10 shows a cross section of the contact member 116a. The contact member 116b is a variation of the contact member with a V-shaped spring portion. The example in FIG. 10 shows a cross section of the contact member 116b. The contact members 116a and 116b can be provided continuously in the circumferential direction of the main body 111, similar to the contact member 116. In addition, the contact members 116a and 116b can suppress plasma leakage by maintaining the electrical connection between the end 75 and the contact member 116, similar to the contact member 116. In addition, the thermal expansion in the horizontal direction and the contact stress in the drive direction of the shutter 60 can be absorbed by the circular and V-shaped spring portions, respectively.

Second Embodiment
In the above-mentioned first embodiment, the contact between the contact member 116 and the end 75 of the baffle plate 70 was maintained by the elasticity of the spring portion 117, but the deformation of the spring portion 117 may be adjusted by a core material, and an embodiment in this case will be described as a second embodiment. Note that the plasma processing apparatus in the second embodiment is similar to the above-mentioned first embodiment except for the core material of the contact member 116, so a description of the overlapping configuration and operation will be omitted.

In plasma processing in the plasma processing apparatus 1, a corrosive gas such as WF6 may be used as the processing gas. In this case, after a long period of operation, the corrosive gas may cause plastic deformation of the spring portion 117 of the contact member 116, reducing the elasticity of the spring portion 117, i.e., reducing the reaction force. Therefore, in the second embodiment, a form in which a core material is provided in the deformation region of the spring portion 117 to maintain the reaction force of the spring portion 117 is described.

Figure 11 is a partially enlarged view showing an example of a cross section near the contact member in the second embodiment. As shown in Figure 11, in the second embodiment, similar to the first embodiment, a contact member 116 is provided in a groove 115a formed in a shield member 115. When a spring portion 117 of the contact member 116 abuts against the gradient shape 76 of the end portion 75 of the baffle plate 70, it is pushed toward the deformation region 118 and elastically deforms. A core material 119 is provided in the deformation region 118 of the contact member 116.

12 is a diagram showing an example of a core material of a contact member in the second embodiment. As shown in FIG. 12, the core material 119 has a V-shaped cross section in the radial direction of the substrate support portion 11. The core material 119 is formed of a material with strong radical resistance, such as a FFKM (perfluoroelastomer) type. That is, the core material 119 is formed of an elastic material such as a fluororubber. The core material 119 may also be formed of a resin such as a PFA (perfluoroalkoxyalkane). The core material 119 is less susceptible to a decrease in reaction force due to wear and corrosion compared to metal materials. When a force is applied to the upper part of the V-shape in the cross section from the left and right directions, the core material 119 elastically deforms so that the V-shape closes, thereby adjusting the amount of elastic deformation of the spring portion 117. That is, when the shutter 60 opens and the end 75 of the baffle plate 70 and the contact member 116 are no longer in contact, the core material 119 pushes the spring portion 117 back to its original shape, thereby maintaining the reaction force of the spring portion 117.

Figure 13 is a perspective view showing an example of a contact member in the second embodiment. As shown in Figure 13, the contact member 116 is formed with multiple spring portions 117 connected in the circumferential direction, and a core material 119 is provided across the multiple spring portions 117. In other words, the core material 119 is provided continuously in the circumferential direction, thereby filling the gaps between the spring portions 117 and further improving the shielding effect. In other words, in the second embodiment, by providing the core material 119, the reaction force of the spring portions 117 can be maintained and plasma leakage can be further suppressed. In other words, in the second embodiment, plastic deformation of the spring portions 117 of the contact member 116 can be suppressed.

Next, other cross-sectional shapes of the core material 119 will be described with reference to Figs. 14 to 16. Figs. 14 to 16 are diagrams showing other examples of the core material of the contact member in the second embodiment. The core material 119a shown in Fig. 14 is disposed in the deformation region 118 of the spring portion 117 in the contact member 116, and has a circular cross section in the radial direction of the board support portion 11. When a force is applied from the left and right direction to the circular shape in the cross section, the core material 119a elastically deforms so that the circle is crushed, thereby adjusting the amount of elastic deformation of the spring portion 117. Note that the core material 119a may have a hollow structure in addition to a solid structure when it is made of a resin such as PFA.

The core material 119b shown in FIG. 15 is disposed in the deformation region 118 of the spring portion 117 in the contact member 116, and has a trapezoidal cross section in the radial direction of the board support portion 11. The core material 119b is a trapezoid whose upper base is longer than its lower base so as to match the cross-sectional shape of the deformation region 118. When a force is applied to the trapezoid from the left and right directions in the cross section, the core material 119b elastically deforms so that the trapezoid is crushed, thereby adjusting the amount of elastic deformation of the spring portion 117.

The core material 119c shown in FIG. 16 is disposed in the deformation region 118 of the spring portion 117 in the contact member 116, and the cross section in the radial direction of the board support portion 11 is a bridge shape. When the core material 119c is removed from the contact member 116, the cross section is H-shaped. The core material 119c is disposed in a deformed state such that the width of the lower side of the H shape is narrowed so as to match the cross-sectional shape of the deformation region 118. In other words, the core material 119c has a shape that is easy to arrange according to the shape of the contact member 116. When a force is applied to the bridge shape (H shape) from the left and right directions in the cross section, the core material 119c elastically deforms so that the bridge portion (the horizontal portion in the center of the H shape) is crushed, thereby adjusting the amount of elastic deformation of the spring portion 117. Note that the cross-sectional shapes of the core materials 119, 119a to 119c are not limited to these shapes as long as they are elastic members that can push the spring portion 117 back to its original shape.

In this way, the contact member 116 including the core material 119 of the second embodiment can maintain the reaction force of the spring portion 117, and can fill the gap between the spring portions 117 to further enhance the shielding effect. In other words, the contact member 116 including the core material 119 of the second embodiment can maintain the reaction force of the spring portion 117 and can further suppress plasma leakage. Note that the contact member 116 may be made of, for example, stainless steel as a conductive elastic member, or may be made of a highly corrosion-resistant metal (for example, a nickel alloy, etc.).

According to each embodiment described above, the substrate processing apparatus (plasma processing apparatus 1) has a chamber (plasma processing chamber 10), a substrate support 11 disposed in the chamber, a shutter 60, and a contact member 116. The shutter 60 includes a valve body 61 that opens and closes the cylindrical chamber opening 50, and a baffle plate 70 disposed between the inner circumference of the chamber and the substrate support 11, with a vertical gradient shape 76 formed on the end 75 on the substrate support 11 side. The contact member 116 is provided on the side of the substrate support 11 and is made of a conductive elastic member. When the shutter 60 is closed, the substrate processing apparatus maintains contact between the end 75 on the substrate support 11 side and the contact member 116. As a result, plasma leakage can be suppressed.

Furthermore, according to each embodiment, the shutter 60 is cylindrical. As a result, parts inside the chamber that exceed the outer diameter of the substrate W can be transported through the chamber opening 50.

In addition, according to each embodiment, the end 75 on the substrate support part 11 side is formed so that its vertical length is longer than the vertical length of the contact member 116. As a result, even if the valve body 61 or the baffle plate 70 expands, the electrical connection (continuity) between the end 75 and the contact member 116 is not broken, and plasma leakage can be suppressed.

In addition, according to each embodiment, the gradient shape 76 is a shape in which the width of the baffle plate 70 narrows from the lower surface side to the upper surface side of the baffle plate 70. As a result, when the shutter 60 is closed, the end portion 75 and the contact member 116 can smoothly come into contact with each other.

According to each embodiment, the baffle plate 70 has a flat portion 71, a wall portion 72, and a flange portion 73. The flat portion 71 has a flat surface having a first width arranged in an annular shape, and has an end portion 75 on the substrate support portion 11 side on the inner periphery. The wall portion 72 is a wall surface having a cylindrical surface perpendicular to the outer periphery of the flat portion 71. The flange portion 73 has a flat surface having a second width arranged in an annular shape on the upper portion of the wall portion 72. As a result, plasma leakage can be suppressed.

In addition, according to each embodiment, the bottom 63 of the valve body 61 is connected to the flange portion 73. As a result, the valve body 61 and the baffle plate 70 can be driven as a unit.

Furthermore, according to each embodiment, the valve body 61 is electrically connected to the baffle plate 70 by sandwiching a conductive member 74 between the bottom portion 63 and the flange portion 73. As a result, the valve body 61 and the baffle plate 70 can be at the same potential.

In addition, according to each embodiment, the baffle plate 70 has a curved connection between the upper portion of the sloped shape 76 of the end portion 75 and the upper surface of the flat portion 71. As a result, when the shutter 60 is closed, the end portion 75 and the contact member 116 can smoothly contact each other.

Furthermore, according to each embodiment, the contact member 116 is provided so as to go around the side surface of the substrate support portion 11. As a result, plasma leakage can be suppressed.

Furthermore, according to the second embodiment, the contact member 116 includes a core material (core materials 119, 119a to 119c) in the deformation region 118 of the elastic member (spring portion 117). As a result, the reaction force of the spring portion 117 can be maintained and plasma leakage can be further suppressed.

In addition, according to the second embodiment, the core material 119a has a circular cross section in the radial direction of the substrate support portion 11. As a result, the reaction force of the spring portion 117 can be maintained and plasma leakage can be further suppressed.

In addition, according to the second embodiment, the core material 119b has a trapezoidal cross section in the radial direction of the substrate support portion 11. As a result, the reaction force of the spring portion 117 can be maintained and plasma leakage can be further suppressed.

In addition, according to the second embodiment, the core material 119 has a V-shaped cross section in the radial direction of the substrate support portion 11. As a result, the reaction force of the spring portion 117 can be maintained and plasma leakage can be further suppressed.

In addition, according to the second embodiment, the core material 119c has a cross-sectional shape in the radial direction of the substrate support portion 11. As a result, the reaction force of the spring portion 117 can be maintained and plasma leakage can be further suppressed.

In addition, according to each embodiment, the valve body 61 has a conductive member 64 on a conductive surface (upper portion 62) at the upper end of the valve body 61 that contacts a conductive upper member (deposit shield 52) provided along the inner wall of the upper portion of the chamber. When the valve body 61 is raised to close the opening 50, the conductive surface of the valve body 61 and the upper member come into contact with the upper member in the vertical direction, and are electrically connected by the conductive member. As a result, the shutter 60 can be made to have the same potential as the plasma processing chamber 10.

Furthermore, according to each embodiment, the substrate processing apparatus has an insulating member 54 that provides insulation between the upper member and the shower head 13 provided on the ceiling of the chamber. As a result, short circuits between the upper member (deposit shield 52) and the valve body 61 and the shower head 13 can be further suppressed.

The embodiments disclosed herein are to be considered in all respects as illustrative and not restrictive. The above embodiments may be omitted, substituted, or modified in various ways without departing from the scope and spirit of the appended claims.

In addition, in each of the above-described embodiments, the contact member 116 is described as having a continuous series of spring portions 117, but is not limited to this. For example, in the contact member 116 shown in FIG. 5, the spring portions 117 may be arranged so that they alternate.

In addition, in each of the above-described embodiments, the end 75 of the baffle plate 70 has an upper portion connected to the flat portion 71, but this is not limited thereto. For example, the lower portion of the end 75 may be connected to the bottom surface of the flat portion 71, that is, the end 75 may be provided so as to protrude upward from the flat portion 71.

In addition, in each of the above-described embodiments, the plasma processing apparatus 1 is described as an example in which a process such as etching is performed on a substrate W using a capacitively coupled plasma as a plasma source, but the disclosed technology is not limited to this. As long as the apparatus is one that performs a process on a substrate W using plasma, the plasma source is not limited to capacitively coupled plasma, and any plasma source can be used, such as inductively coupled plasma, microwave plasma, magnetron plasma, etc.

The present disclosure can also be configured as follows.
(1)
A substrate processing apparatus, comprising:
A chamber;
a substrate support disposed within the chamber;
a shutter including a valve body that opens and closes an opening of the cylindrical chamber, and a baffle plate that is disposed between an inner periphery of the chamber and the substrate support portion, the baffle plate having a vertical gradient formed on an end portion on the substrate support portion side;
a contact member provided on a side surface of the substrate support portion and made of a conductive elastic member;
having
When the shutter is closed, contact between the end portion on the substrate support portion side and the contact member is maintained.
Substrate processing equipment.
(2)
The shutter is cylindrical.
The substrate processing apparatus according to (1) above.
(3)
the end portion on the substrate support portion side is formed so that the length in the vertical direction is longer than the length in the vertical direction of the contact member;
The substrate processing apparatus according to (1) or (2).
(4)
The gradient shape is a shape in which the width of the baffle plate narrows from the lower surface side to the upper surface side of the baffle plate.
The substrate processing apparatus according to any one of (1) to (3).
(5)
The baffle plate is
a flat surface portion having a first width and provided in an annular shape, the flat surface portion including the end portion on the substrate support portion side on an inner circumferential side;
A wall portion having a cylindrical surface that is perpendicular to the outer periphery of the flat portion;
a flange portion having a flat surface having a second width and provided in an annular shape on an upper portion of the wall portion;
having
The substrate processing apparatus according to any one of (1) to (4).
(6)
The valve body has a bottom portion connected to the flange portion.
The substrate processing apparatus according to (5) above.
(7)
The valve body is electrically connected to the baffle plate by sandwiching a conductive member between the bottom portion and the flange portion.
The substrate processing apparatus according to (6) above.
(8)
The baffle plate has a curved surface at a connection between an upper portion of the inclined shape of the end portion and an upper surface of the flat portion.
The substrate processing apparatus according to any one of (5) to (7).
(9)
The contact member is provided so as to go around a side surface of the substrate support portion.
The substrate processing apparatus according to any one of (1) to (8).
(10)
The contact member includes a core material in a deformation region of the elastic member.
The substrate processing apparatus according to any one of (1) to (9).
(11)
The core member has a circular cross section in a radial direction of the substrate support portion.
The substrate processing apparatus according to (10) above.
(12)
The core member has a trapezoidal cross section in a radial direction of the substrate support portion.
The substrate processing apparatus according to (10) above.
(13)
The core member has a V-shaped cross section in a radial direction of the substrate support portion.
The substrate processing apparatus according to (10) above.
(14)
The core material has a cross-section in a radial direction of the substrate support portion having a bridge shape.
The substrate processing apparatus according to (10) above.
(15)
the valve body includes a conductive member on a conductive surface at an upper end of the valve body, the conductive surface being in contact with a conductive upper member provided along an inner wall of an upper portion of the chamber;
When the valve body is raised to close the opening, the conductive surface of the valve body and the upper member are brought into contact with the upper member in a vertical direction, and are electrically connected to each other by the conductive member.
The substrate processing apparatus according to any one of (1) to (14).
(16)
an insulating member for insulating the upper member from a shower head provided on the ceiling of the chamber;
The substrate processing apparatus according to (15) above.
(17)
A shutter provided at an opening of a chamber of a substrate processing apparatus,
a valve body for opening and closing an opening of the cylindrical chamber;
a baffle plate disposed between an inner periphery of the chamber and a substrate support disposed within the chamber, the baffle plate having a vertical gradient formed at an end portion thereof facing the substrate support;
having
When the shutter is in a closed state, contact is maintained between the end portion on the substrate support portion and a contact member formed of a conductive elastic member and provided on a side surface of the substrate support portion.
Shutter.
(18)
The contact member includes a core material in a deformation region of the elastic member.
The shutter according to (17) above.

REFERENCE SIGNS LIST 1 plasma processing apparatus 10 plasma processing chamber 11 substrate support portion 50 opening 52 deposit shield 54 insulating member 60 shutter 61 valve body 63 bottom portion 70 baffle plate 71 flat portion 72 wall portion 73 flange portion 74 conductive member 75 end portion 76 gradient shape 111 main body portion 116 contact member 117 spring portion 119, 119a to 119c core material W substrate

Claims (18)

A substrate processing apparatus, comprising:
A chamber;
a substrate support disposed within the chamber;
a shutter including a valve body that opens and closes an opening of the cylindrical chamber, and a baffle plate that is disposed between an inner periphery of the chamber and the substrate support portion, the baffle plate having a vertical gradient formed on an end portion on the substrate support portion side;
a contact member provided on a side surface of the substrate support portion and made of a conductive elastic member;
having
When the shutter is closed, contact between the end portion on the substrate support portion side and the contact member is maintained.
Substrate processing equipment. The shutter is cylindrical.
The substrate processing apparatus according to claim 1 . the end portion on the substrate support portion side is formed so that the length in the vertical direction is longer than the length in the vertical direction of the contact member;
The substrate processing apparatus according to claim 1 . The gradient shape is a shape in which the width of the baffle plate narrows from the lower surface side to the upper surface side of the baffle plate.
The substrate processing apparatus according to claim 1 . The baffle plate is
a flat surface portion having a first width and provided in an annular shape, the flat surface portion including the end portion on the substrate support portion side on an inner circumferential side;
A wall portion having a cylindrical surface that is perpendicular to the outer periphery of the flat portion;
a flange portion having a flat surface having a second width and provided in an annular shape on an upper portion of the wall portion;
having
The substrate processing apparatus according to claim 1 . The valve body has a bottom portion connected to the flange portion.
The substrate processing apparatus according to claim 5 . The valve body is electrically connected to the baffle plate by sandwiching a conductive member between the bottom portion and the flange portion.
The substrate processing apparatus according to claim 6 . The baffle plate has a curved surface at a connection between an upper portion of the inclined shape of the end portion and an upper surface of the flat portion.
The substrate processing apparatus according to claim 5 . The contact member is provided so as to go around a side surface of the substrate support portion.
The substrate processing apparatus according to claim 1 . The contact member includes a core material in a deformation region of the elastic member.
The substrate processing apparatus according to claim 1 . The core member has a circular cross section in a radial direction of the substrate support portion.
The substrate processing apparatus according to claim 10 . The core member has a trapezoidal cross section in a radial direction of the substrate support portion.
The substrate processing apparatus according to claim 10 . The core member has a V-shaped cross section in a radial direction of the substrate support portion.
The substrate processing apparatus according to claim 10 . The core material has a cross-section in a radial direction of the substrate support portion having a bridge shape.
The substrate processing apparatus according to claim 10 . the valve body includes a conductive member on a conductive surface at an upper end of the valve body, the conductive surface being in contact with a conductive upper member provided along an inner wall of an upper portion of the chamber;
When the valve body is raised to close the opening, the conductive surface of the valve body and the upper member are brought into contact with the upper member in the vertical direction, and are electrically connected to each other by the conductive member.
The substrate processing apparatus according to claim 1 . an insulating member for insulating the upper member from a shower head provided on the ceiling of the chamber;
The substrate processing apparatus of claim 15 . A shutter provided at an opening of a chamber of a substrate processing apparatus,
a valve body for opening and closing an opening of the cylindrical chamber;
a baffle plate disposed between an inner periphery of the chamber and a substrate support disposed within the chamber, the baffle plate having a vertical gradient formed at an end portion thereof facing the substrate support;
having
When the shutter is in a closed state, contact is maintained between the end portion on the substrate support portion side and a contact member that is provided on a side surface of the substrate support portion and is made of a conductive elastic member.
Shutter. The contact member includes a core material in a deformation region of the elastic member.
20. The shutter of claim 17.

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