Plasma processing apparatus and substrate support

Abstract

To provide a plasma processing apparatus and a substrate support part which can suppress abnormal discharge of a heat transfer gas supply hole.SOLUTION: A plasma processing apparatus has a plasma processing container, and a substrate support part which is arranged in the plasma processing container and has a support surface above a base, wherein the substrate support part includes a heat transfer gas supply hole for supplying heat transfer gas to a support surface from the base side, a first member which is arranged on the support surface side in the heat transfer gas supply hole and is constituted of silicon carbide, a second member which is arranged below the first member in the heat transfer gas supply hole and is constituted of a porous resin, and a third member which is arranged below the second member in the heat transfer gas supply hole and is constituted of PTFE.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present disclosure relates to a plasma processing apparatus and a substrate support. [Background technology]

[0002] In a plasma processing apparatus, a substrate support part for supporting a substrate to be processed is provided in a plasma processing chamber in which plasma processing is performed. The substrate support part has a supply hole for supplying a heat transfer gas between the rear surface of the substrate placed on the substrate support part and the support surface of the substrate support part. Abnormal discharge may occur in the supply hole during plasma processing. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2019-220555 A Summary of the Invention [Problem to be solved by the invention]

[0004] The present disclosure provides a plasma processing apparatus and a substrate support unit capable of suppressing abnormal discharge in a heat transfer gas supply hole. [Means for solving the problem]

[0005] A plasma processing apparatus according to one embodiment of the present disclosure includes a plasma processing vessel, and a substrate support portion disposed within the plasma processing vessel and having a support surface on an upper portion of a base, the substrate support portion including a heat transfer gas supply hole that supplies a heat transfer gas from the base side to the support surface, a first member disposed on the support surface side within the heat transfer gas supply hole and made of silicon carbide, a second member disposed below the first member within the heat transfer gas supply hole and made of porous resin, and a third member disposed below the second member within the heat transfer gas supply hole and made of PTFE (polytetrafluoroethylene). Effect of the Invention

[0006] According to the present disclosure, abnormal discharge in the heat transfer gas supply holes can be suppressed. [Brief description of the drawings]

[0007] [Figure 1] FIG. 1 is a diagram illustrating an example of a plasma processing system according to a first embodiment of the present disclosure. [Diagram 2] FIG. 2 is a partial enlarged view showing an example of a cross section of the substrate support portion of the first embodiment. [Diagram 3] FIG. 3 is a partially enlarged view showing an example of a cross section of a heat transfer gas supply hole of a reference example. [Figure 4] FIG. 4 is a diagram showing an example of a second member of a rod according to a reference example. [Diagram 5] FIG. 5 is a partially enlarged view showing an example of a cross section of a heat transfer gas supply hole of the first embodiment. [Figure 6] FIG. 6 is a partial enlarged view showing an example of a cross section of a heat transfer gas supply hole of the first modification. [Figure 7] FIG. 7 is a partial enlarged view showing an example of a cross section of a heat transfer gas supply hole of the second modification. [Figure 8] FIG. 8 is a partial enlarged view showing an example of a cross section of a heat transfer gas supply hole of the second embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of the plasma processing apparatus and the substrate support unit will be described in detail with reference to the accompanying drawings. Note that the disclosed technology is not limited to the following preferred embodiments.

[0009] In order to suppress abnormal discharge in the heat transfer gas supply hole during plasma processing, it has been proposed to place an embedding member with an uneven surface in the supply hole. In this case, the heat transfer gas is supplied to the support surface through the gap created by the unevenness. However, when the pressure of the heat transfer gas is increased to cool the substrate or edge ring placed on the substrate support, abnormal discharge may occur in the gap between the embedding member and the supply hole according to Paschen's law. Therefore, it is expected that abnormal discharge in the heat transfer gas supply hole will be suppressed even when the pressure of the heat transfer gas is increased.

[0010] (First embodiment) [Configuration of plasma processing system] A configuration example of the 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 may include the control unit 2. The capacitively coupled plasma processing apparatus 1 includes a plasma processing chamber 10, a gas supply unit 20, a power source 30, an exhaust system 40, and a heat transfer gas supply unit 60. 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 a ceiling of the plasma processing chamber 10. The plasma processing chamber 10 has a plasma processing space 10s defined by a showerhead 13, a sidewall 10a of the plasma processing chamber 10, and a substrate support 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. The sidewall 10a is grounded. The showerhead 13 and the substrate support 11 are electrically insulated from the plasma processing chamber 10 housing.

[0011] The substrate support 11 includes a main body 111 and a ring assembly 112. The main body 111 has a central region (substrate support surface) 111a for supporting a substrate (wafer) W, and an annular region (ring support surface) 111b for supporting the ring assembly 112. 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. In one embodiment, the main body 111 includes a base and an electrostatic chuck. The base includes a conductive member. The conductive member of the base functions as a lower electrode. The electrostatic chuck is disposed on the base. The upper surface of the electrostatic chuck has a substrate support surface 111a. The ring assembly 112 includes one or more annular members. At least one of the one or more annular members is an edge ring. Although not shown, the substrate support 11 may include a temperature adjustment module configured to adjust at least one of the electrostatic chuck, 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 path, or a combination thereof. A heat transfer fluid such as brine or gas flows through the flow path. The substrate support 11 also includes a heat transfer gas supply unit 60 configured to supply a heat transfer gas between the back surface of the substrate W and the substrate support surface 111a, and between the ring assembly 112 and the ring support surface 111b, via the heat transfer gas supply path 50 and the heat transfer gas supply hole 50a. Furthermore, a rod 52 is arranged in the heat transfer gas supply hole 50a to suppress abnormal discharge at the heat transfer gas supply hole 50a.

[0012] 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 a conductive member. The conductive member of the shower head 13 functions as an 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 side wall 10a.

[0013] 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 a flow rate of the at least one process gas.

[0014] 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), such as a source RF signal and a bias RF signal, to a conductive member of the substrate support 11 and / or a conductive member of the showerhead 13. 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 a plasma from one or more processing gases in the plasma processing chamber 10. In addition, by supplying a bias RF signal to the conductive member of the substrate support 11, a bias potential is generated on the substrate W, and ion components in the formed plasma can be attracted to the substrate W.

[0015] In one embodiment, the RF power supply 31 includes a first RF generating unit 31a and a second RF generating unit 31b. The first RF generating unit 31a is coupled to the conductive member of the substrate support 11 and / or the conductive member of the shower head 13 via at least one impedance matching circuit, and is 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 13 MHz to 150 MHz. In one embodiment, the first RF generating unit 31a may be configured to generate a plurality of source RF signals having different frequencies. The generated one or more source RF signals are supplied to the conductive member of the substrate support 11 and / or the conductive member of the shower head 13. The second RF generating unit 31b is coupled to the conductive member of the substrate support 11 via at least one impedance matching circuit, and is configured to generate a bias RF signal (bias RF power). In one embodiment, the bias RF signal has a lower frequency than the source RF signal. In one embodiment, the bias RF signal has a frequency in the range of 400 kHz to 13.56 MHz. In one embodiment, the second RF generator 31b may be configured to generate multiple bias RF signals having different frequencies. The generated bias RF signal or signals are provided to the conductive members of the substrate support 11. Also, in various embodiments, at least one of the source RF signal and the bias RF signal may be pulsed.

[0016] 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 a conductive member of the substrate support 11 and configured to generate a first DC signal. The generated first bias DC signal is applied to the conductive member of the substrate support 11. In one embodiment, the first DC signal may be applied to another electrode, such as an electrode in an electrostatic chuck. In one embodiment, the second DC generator 32b is connected to a conductive member of the showerhead 13 and configured to generate a second DC signal. The generated second DC signal is applied to the conductive member of the showerhead 13. In various embodiments, at least one of the first and second DC signals may be pulsed. The first and second DC generating units 32a, 32b may be provided in addition to the RF power supply 31, or the first DC generating unit 32a may be provided in place of the second RF generating unit 31b.

[0017] 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.

[0018] The heat transfer gas supply unit 60 supplies a heat transfer gas (gas for transferring cold heat) to the heat transfer gas supply holes 50a provided in the base of the substrate support unit 11 and the electrostatic chuck through the heat transfer gas supply path 50. As the heat transfer gas, for example, helium gas is used. The heat transfer gas is supplied from the heat transfer gas supply holes 50a in the substrate support surface 111a and the ring support surface 111b to between the rear surface of the substrate W and the substrate support surface 111a, and between the ring assembly 112 and the ring support surface 111b. By supplying the heat transfer gas, heat is removed from the substrate W and the edge ring that have been heated by the plasma processing and become high in temperature.

[0019] The control unit 2 processes computer-executable instructions that cause the plasma processing apparatus 1 to perform various steps described in the present disclosure. The control unit 2 may be configured to control each element of the plasma processing apparatus 1 to perform 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, for example, a computer 2a. The computer 2a may include, for example, a processing unit (CPU: Central Processing Unit) 2a1, a storage unit 2a2, and a communication interface 2a3. The processing unit 2a1 may be configured to perform various control operations based on a program stored in the storage unit 2a2. The storage unit 2a2 may include a random access memory (RAM), a read only memory (ROM), a hard disk drive (HDD), a solid state drive (SSD), or a combination thereof. The communication interface 2a3 may communicate with the plasma processing apparatus 1 via a communication line such as a local area network (LAN).

[0020] [Arrangement of heat transfer gas supply holes 50a] Next, the arrangement of the heat transfer gas supply holes 50a in the substrate support part 11 will be described with reference to FIG. 2. FIG. 2 is a partially enlarged view showing an example of a cross section of the substrate support part of the first embodiment. As shown in FIG. 2, an electrostatic chuck 113 is provided on the upper part of the main body part 111 of the substrate support part 11, and the upper surface of the electrostatic chuck 113 is the substrate support surface 111a and the ring support surface 111b. The electrostatic chuck 113 is made of, for example, a ceramic plate. The openings 114, 114a in the electrostatic chuck 113 constitute the uppermost part of the heat transfer gas supply holes 50a. The heat transfer gas supply holes 50a are constituted by the sleeve 51 and the openings 114, 114a of the electrostatic chuck 113, and a plurality of the heat transfer gas supply holes 50a are provided in each of the substrate support surface 111a and the ring support surface 111b. The sleeve 51 is made of, for example, alumina (Al2O3). FIG. 2 shows a cross section of a portion of each of the heat transfer gas supply holes 50a provided in the substrate supporting surface 111a and the ring supporting surface 111b.

[0021] A rod 52 is disposed in the heat transfer gas supply hole 50a. The portion of the rod 52 disposed in the openings 114, 114a is composed of the first members 53, 53a. Note that the region 120 of the heat transfer gas supply hole 50a provided in the substrate support surface 111a and the region 121 of the heat transfer gas supply hole 50a provided in the ring support surface 111b have the same configuration except for the thickness of the electrostatic chuck 113, so in the following description, the region 120 will be described as an example.

[0022] [Cross section of heat transfer gas supply hole for reference example] Here, a cross section of a heat transfer gas supply hole of a reference example in which an embedded member having an uneven surface is disposed in the supply hole will be described with reference to Figs. 3 and 4. Fig. 3 is a partially enlarged view showing an example of a cross section of a heat transfer gas supply hole of a reference example. Fig. 4 is a view showing an example of a second member of a rod of a reference example. As shown in Figs. 3 and 4, in the reference example, a rod 200 is disposed in the heat transfer gas supply hole 50a instead of the rod 52. Also, the rod 200 has a first member 201 instead of the first member 53, and the first member 201 is connected to a second member 202. The second member 202 has a protrusion 203 for preventing falling, a notch 204 for transmitting the heat transfer gas, and a hole 205 for inserting the first member 201. The first member 201 is connected to the upper part of the second member 202 by fitting a protrusion 206 provided in the lower part into the hole 205.

[0023] In region 120, opening 114 of electrostatic chuck 113 is connected to heat transfer gas supply hole 50a in sleeve 51 directly below through an opening in adhesive layer 116. The inner diameter of opening 114, which is the uppermost part of heat transfer gas supply hole 50a, is smaller than the inner diameter of heat transfer gas supply hole 50a in sleeve 51. The upper surface of second member 202 contacts the lower surface of electrostatic chuck 113 so as to surround the outer periphery of heat transfer gas supply hole 50a in the lower surface of electrostatic chuck 113.

[0024] In the heat transfer gas supply hole 50a, the heat transfer gas flows in the order of the flow paths 210 to 212. The flow path 210 is a gap between the second member 202 and the sleeve 51. The flow path 211 is a notch portion 204 connected to the flow path 210. The flow path 212 is a gap between the first member 201 and the inner wall of the opening 114 of the electrostatic chuck 113, which is connected to the notch portion 204. Note that in FIG. 3 and FIG. 4, arrows are attached to the vicinity of the flow paths. In the rod 200 of the reference example, when the pressure of the heat transfer gas is increased, electrons ionized from the helium of the heat transfer gas are accelerated by receiving a potential difference in a gap such as the space in the notch portion 204, and abnormal discharge may occur. That is, a potential difference is easily generated in the gas flow path near the joint between the ceramic plate of the electrostatic chuck 113 and the sleeve 51 made of alumina, and abnormal discharge may occur in the gas flow path. Therefore, it is necessary to suppress abnormal discharge above the heat transfer gas supply holes 50a.

[0025] [Cross section of heat transfer gas supply hole in first embodiment] Next, a cross section of the heat transfer gas supply hole in the first embodiment will be described with reference to FIG. 5. FIG. 5 is a partially enlarged view showing an example of a cross section of the heat transfer gas supply hole in the first embodiment. As shown in FIG. 5, in the first embodiment, a cylindrical rod 52 is disposed in the heat transfer gas supply hole 50a. The rod 52 has a first member 53, which is a portion disposed in the opening 114, a second member 54 disposed below the first member 53, and a third member 55 disposed below the second member 54. Note that FIG. 5 also shows a part of the electrode 115 provided inside the electrostatic chuck 113.

[0026] The first member 53 is made of silicon carbide (SiC) and has a gap between it and the inner wall of the heat transfer gas supply hole 50a (the inner wall of the opening 114) in the electrostatic chuck 113. The gap is, for example, 0.01 mm to 0.4 mm. The length of the first member 53 corresponds to at least the thickness of the electrostatic chuck 113. The first member 53 reduces the potential difference in the vicinity of the opening 114 of the electrostatic chuck 113. The first member 53 may be made of other ceramics such as alumina (Al2O3). The second member 54 is made of a porous resin and is in contact with the inner wall of the heat transfer gas supply hole 50a inside the sleeve 51 and on the lower surface of the electrostatic chuck 113 without having a gap. The porous resin is a resin having a porous structure, and examples of the resin that can be used include PI (polyimide), PTFE, PCTFE (polychlorotrifluoroethylene), PFA (perfluoroalkoxyalkane resin), PEEK (polyetheretherketone), PEI (polyetherimide), POM (poly oxymethylene, polyacetal, polyformaldehyde), MC (methyl cellulose), PC (polycarbonate), and PPS (poly phenylene sulfone). For example, PTFE is preferably used as the porous resin. Note that there may be a slight gap between the second member 54 and the inner wall of the heat transfer gas supply hole 50a, or the second member 54 having a diameter larger than the inner diameter of the heat transfer gas supply hole 50a may be press-fitted. That is, the gap between the second member 54 and the inner wall of the heat transfer gas supply hole 50a may be in the range of -0.2 mm to +0.2 mm, for example.

[0027] In the region 120 of the first embodiment, similarly to the reference example, the opening 114 of the electrostatic chuck 113 is connected to the heat transfer gas supply hole 50a in the sleeve 51 directly below through an opening in the adhesive layer 116. The inner diameter of the opening 114 at the top of the heat transfer gas supply hole 50a is smaller than the inner diameter of the heat transfer gas supply hole 50a in the sleeve 51. The upper surface of the second member 54 is in contact with the lower surface of the electrostatic chuck 113 without any gap so as to surround the outer periphery of the heat transfer gas supply hole 50a in the lower surface of the electrostatic chuck 113.

[0028] The third member 55 is made of resin, for example, PTFE, and is disposed in the sleeve 51 so as to have a gap between the third member 55 and the inner wall of the heat transfer gas supply hole 50a. The gap is, for example, 0.01 mm to 0.6 mm. As shown in FIG. 5, the rod 52 is in contact with the first member 53, the second member 54, and the third member 55, in that order from the upper surface side of the electrostatic chuck 113. That is, the lower surface of the first member 53 is in contact with the upper surface of the second member 54, and the lower surface of the second member 54 is in contact with the upper surface of the third member 55. Note that the rod 52 does not need to be bonded between the first member 53 and the second member 54. The rod 52 is bonded to the second member 54 and the third member 55, but if a protrusion for preventing the rod 52 from falling is provided on the third member 55, the second member 54 and the third member 55 do not need to be bonded to each other. Although the rod 52 is not bonded to the heat transfer gas supply hole 50a, the second member 54 and the third member 55 are fixed inside the heat transfer gas supply hole 50a.

[0029] In the heat transfer gas supply hole 50a, the heat transfer gas flows in the order of the flow paths 56 to 58. The flow path 56 is a gap between the third member 55 and the sleeve 51. The flow path 57 is a flow path that passes through the porous structure inside the second member 54, which is connected to the flow path 56. The flow path 58 is a gap between the first member 53 and the inner wall of the opening 114 of the electrostatic chuck 113, which is connected to the flow path 57. In FIG. 5, the flow of the heat transfer gas is indicated by arrows near the flow paths. That is, in the first embodiment, the heat transfer gas is supplied to the substrate support surface 111a through the gap between the third member 55 and the inner wall of the heat transfer gas supply hole 50a (sleeve 51), the inside of the second member 54, and the gap between the first member 53 and the inner wall of the heat transfer gas supply hole 50a (inside the opening 114). In the rod 52, even if the pressure of the heat transfer gas is increased, there is no space near the lower surface of the electrostatic chuck 113 and the upper part of the sleeve 51, so that electrons do not travel in a straight line and the acceleration of electrons is suppressed, thereby suppressing abnormal discharge in the heat transfer gas supply hole 50a. That is, by sandwiching the second member 54, which is a porous resin, between the first member 53, which is silicon carbide (SiC), and the sleeve 51, which is alumina (Al2O3), the first member 53 and the sleeve 51 are not directly exposed to each other, so that abnormal discharge in the heat transfer gas supply hole 50a can be suppressed.

[0030] [Variation 1] Next, a first modified example in which the structure of the upper part of the rod 52 is changed will be described with reference to Fig. 6. Fig. 6 is a partial enlarged view showing an example of a cross section of a heat transfer gas supply hole in the first modified example. Note that a part of the configuration of the plasma processing apparatus in the first modified example is similar to that of the first embodiment described above, and therefore a description of the overlapping configuration and operation will be omitted.

[0031] 6, in Modification 1, rod 52a is disposed in heat transfer gas supply hole 50a. Rod 52a has a first member 53b which is a portion disposed in opening 114, a second member 54a disposed below first member 53b, and a third member 55a disposed below second member 54a.

[0032] The first member 53b is made of silicon carbide (SiC) like the first member 53, and has a gap between it and the inner wall of the heat transfer gas supply hole 50a (the inner wall of the opening 114) in the electrostatic chuck 113. The gap is, for example, 0.01 mm to 0.4 mm. The lower part of the first member 53b extends into the sleeve 51, penetrates the second member 54a, and is fixed to the upper part of the third member 55a. The second member 54a is made of a porous resin, and is in contact with the inner wall of the heat transfer gas supply hole 50a inside the sleeve 51 and on the lower surface of the electrostatic chuck 113 without a gap. The gap between the second member 54a and the inner wall of the heat transfer gas supply hole 50a can be, for example, in the range of -0.2 mm to +0.2 mm, like the first embodiment. The second member 54a is shorter in the length direction (vertical direction) than the second member 54, and the lower part of the first member 53b penetrates through the center. The second member 54a is in contact with the side surface of the first member 53b through which it penetrates, without leaving a gap. Note that the upper surface of the second member 54a is in contact with the lower surface of the electrostatic chuck 113 without leaving a gap so as to surround the outer periphery of the heat transfer gas supply hole 50a in the lower surface of the electrostatic chuck 113, as in the first embodiment.

[0033] The third member 55a is made of resin, for example, PTFE, and is disposed in the sleeve 51 so as to have a gap between the third member 55a and the inner wall of the heat transfer gas supply hole 50a. The gap is, for example, 0.01 mm to 0.6 mm. The third member 55a has a protrusion 55b for preventing the third member 55a from falling. The lower part of the first member 53b is fitted and fixed to the upper part of the third member 55a. As shown in FIG. 6, the rod 52a is in contact with the first member 53b, the second member 54a, and the third member 55a in this order from the upper surface side of the electrostatic chuck 113. The rod 52a is in a state in which the first member 53b is fixed to the third member 55a via the second member 54a, and the first member 53b, the second member 54a, and the third member 55a are integrated.

[0034] In the heat transfer gas supply hole 50a of the first modification, the heat transfer gas flows through the flow passage 56, the flow passage 57a, and the flow passage 58 in this order. The flow passage 56 is a gap between the third member 55a and the sleeve 51. The flow passage 57a is a flow passage that passes through the porous structure inside the second member 54a and is connected to the flow passage 56. The flow passage 57a is shorter than the flow passage 57, and the heat transfer gas flows easily through the flow passage 57a. That is, the flow passage 57a has a larger conductance than the flow passage 57. The length of the second member 54a can be determined by a trade-off between the conductance and the suppression of abnormal discharge. The flow passage 58 is a gap between the first member 53b and the inner wall of the opening 114 of the electrostatic chuck 113 and is connected to the flow passage 57a. In FIG. 6, the flow of the heat transfer gas is indicated by arrows near the flow passages. That is, in variant example 1, the heat transfer gas is supplied to the substrate support surface 111a through the gap between the third member 55a and the inner wall of the heat transfer gas supply hole 50a (sleeve 51), the inside of the second member 54a, and the gap between the first member 53b and the inner wall of the heat transfer gas supply hole 50a (inside the opening 114).

[0035] In the rod 52a, even if the pressure of the heat transfer gas is increased, there is no space near the lower surface of the electrostatic chuck 113 and the upper part of the sleeve 51, so that the electrons do not travel in a straight line and the acceleration of the electrons is suppressed, thereby suppressing abnormal discharge in the heat transfer gas supply hole 50a. In addition, since the distance that the heat transfer gas flows in the second member 54a made of porous resin is short, the conductance of the heat transfer gas supply hole 50a can be made larger than that of the rod 52 of the first embodiment.

[0036] [Variation 2] Next, a second modification in which the structure of the upper part of the rod 52 is changed will be described with reference to Fig. 7. Fig. 7 is a partial enlarged view showing an example of a cross section of a heat transfer gas supply hole in the second modification. Note that a part of the configuration of the plasma processing apparatus in the second modification is similar to that of the first embodiment described above, and therefore a description of the overlapping configuration and operation will be omitted.

[0037] 7, in Modification 2, rod 52b is disposed in heat transfer gas supply hole 50a. Rod 52b has a first member 53c which is a portion disposed in opening 114, a second member 54b disposed below first member 53c, and a third member 55c disposed below second member 54b.

[0038] The first member 53c is made of silicon carbide (SiC) like the first member 53, and has a gap between it and the inner wall of the heat transfer gas supply hole 50a (the inner wall of the opening 114) in the electrostatic chuck 113. The gap is, for example, 0.01 mm to 0.4 mm. The lower part of the first member 53c extends into the sleeve 51 and is fitted and fixed to the upper part of the second member 54b. The second member 54b is made of a porous resin, and is in contact with the inner wall of the heat transfer gas supply hole 50a inside the sleeve 51 and on the lower surface of the electrostatic chuck 113 without a gap. The distance between the second member 54b and the inner wall of the heat transfer gas supply hole 50a can be, for example, in the range of -0.2 mm to +0.2 mm, like the first embodiment. Compared to the second member 54, the second member 54b has a hole in its upper part for fitting the lower part of the first member 53c. As in the first embodiment, the upper surface of the second member 54b is in contact with the lower surface of the electrostatic chuck 113 without any gaps so as to surround the outer periphery of the heat transfer gas supply hole 50a in the lower surface of the electrostatic chuck 113.

[0039] The third member 55c is made of a resin, such as PTFE, and is disposed in the sleeve 51 so as to have a gap between it and the inner wall of the heat transfer gas supply hole 50a. The gap is, for example, 0.01 mm to 0.6 mm. The lower part of the second member 54b is fixed to the upper part of the third member 55c by adhesive or the like. As shown in FIG. 7, the rod 52b is in contact with the first member 53c, the second member 54b, and the third member 55c in that order from the upper surface side of the electrostatic chuck 113.

[0040] In the heat transfer gas supply hole 50a of the second modification, the heat transfer gas flows through the flow paths 56 to 58 in this order. The flow path 56 is a gap between the third member 55c and the sleeve 51. The flow path 57 is a flow path that passes through the porous structure inside the second member 54b, which is connected to the flow path 56. The flow path 58 is a gap between the first member 53c and the inner wall of the opening 114 of the electrostatic chuck 113, which is connected to the flow path 57. In FIG. 7, arrows are added near the flow paths to indicate the flow of the heat transfer gas. That is, in the second modification, the heat transfer gas is supplied to the substrate support surface 111a through the gap between the third member 55c and the inner wall of the heat transfer gas supply hole 50a (sleeve 51), the inside of the second member 54b, and the gap between the first member 53c and the inner wall of the heat transfer gas supply hole 50a (inside the opening 114).

[0041] In rod 52b, even if the pressure of the heat transfer gas is increased, there is no space near the lower surface of electrostatic chuck 113 and the upper part of sleeve 51, so that electrons do not travel in a straight line and the acceleration of electrons is suppressed, thereby suppressing abnormal discharge in heat transfer gas supply hole 50a.

[0042] Second embodiment In the above-described first embodiment, the first members 53, 53a to 53c made of silicon carbide (SiC) are provided in the opening 114 of the electrostatic chuck 113, but a porous member may be provided in the opening 114 of the electrostatic chuck 113, and an embodiment in this case will be described as a second embodiment. Note that the same components as those in the plasma processing apparatus 1 of the first embodiment are denoted by the same reference numerals, and descriptions of the overlapping components and operations will be omitted.

[0043] FIG. 8 is a partially enlarged view showing an example of a cross section of the heat transfer gas supply hole of the second embodiment. As shown in FIG. 8, in the second embodiment, an opening 114b having a diameter larger than the opening at the top of the sleeve 51, that is, the inner diameter of the heat transfer gas supply hole 50a in the sleeve 51 is provided in the electrostatic chuck 113a. The opening 114b is formed, for example, by countersinking. In addition, an opening having the same diameter as the opening 114b is provided in the adhesive layer 116. In the second embodiment, the rod 52c is provided in the heat transfer gas supply hole 50a of the sleeve 51 so that the upper end of the sleeve 51 and the upper end of the rod 52c are at the same height. Next, a porous member 59 is inserted into the opening 114b from the upper surface side of the electrostatic chuck 113a and is bonded to the upper surfaces of the sleeve 51 and the rod 52c. Note that the adhesive is not attached to the portion corresponding to the gap between the sleeve 51 and the rod 52c. Also, the porous member 59 may be bonded to the upper surface of the rod 52c in advance and then inserted into the heat transfer gas supply hole 50a. In this case, by making the diameter of the porous member 59 larger than the diameter of the opening 114b and press-fitting it, the rod 52c and the porous member 59 can be fixed without using adhesive.

[0044] The side surface of the porous member 59 is in contact with the opening 114b and the inner wall of the opening of the adhesive layer 116 without leaving any gaps. The lower surface of the porous member 59 is in contact with the upper surfaces of the sleeve 51 and the rod 52c without leaving any gaps. The porous member 59 is made of, for example, a porous resin, similar to the second member 54 of the first embodiment.

[0045] The rod 52c is made of a resin, for example, PTFE, similarly to the third member 55 in the first embodiment, and is disposed within the sleeve 51 so as to have a gap between it and the inner wall of the heat transfer gas supply hole 50a.

[0046] In the heat transfer gas supply hole 50a in the second embodiment, the heat transfer gas flows through the flow paths 56a and 58a in this order. The flow path 56a is a gap between the rod 52c and the sleeve 51. The flow path 58a is a flow path that passes through the porous structure inside the porous member 59, which is connected to the flow path 56a. In FIG. 8, the flow of the heat transfer gas is indicated by arrows near the flow paths. That is, in the second embodiment, the heat transfer gas is supplied to the substrate support surface 111a through the gap between the rod 52c and the inner wall of the heat transfer gas supply hole 50a (sleeve 51) and through the inside of the porous member 59. In the rod 52c, even if the pressure of the heat transfer gas is increased, there is no space near the lower surface of the electrostatic chuck 113 and the upper part of the sleeve 51, so that the electrons do not move in a straight line, and the acceleration of the electrons is suppressed, so that the abnormal discharge of the heat transfer gas supply hole 50a can be suppressed.

[0047] As described above, according to the first embodiment, the plasma processing apparatus 1 includes a plasma processing container (plasma processing chamber 10) and a substrate support 11 disposed in the plasma processing container and having a support surface (substrate support surface 111a, ring support surface 111b) on the upper part of a base. The substrate support 11 includes a heat transfer gas supply hole 50a for supplying a heat transfer gas from the base side to the support surface, first members 53, 53a to 53c disposed on the support surface side in the heat transfer gas supply hole 50a and made of silicon carbide, second members 54, 54a, 54b disposed below the first members 53, 53a to 53c in the heat transfer gas supply hole 50a and made of porous resin, and third members 55, 55a, 55c disposed below the second members 54, 54a, 54b in the heat transfer gas supply hole 50a and made of PTFE. As a result, abnormal discharge in the heat transfer gas supply hole 50a can be suppressed.

[0048] According to the first embodiment, the second members 54, 54a, 54b are arranged so as to have no gap between them and the inner wall of the heat transfer gas supply hole 50a. As a result, the heat transfer gas can flow inside the second members 54, 54a, 54b.

[0049] According to the first embodiment, the first members 53, 53a to 53c have a length at least corresponding to the thickness of the ceramic plate (electrostatic chuck 113) provided on the support surface of the heat transfer gas supply hole 50a. As a result, the potential difference can be reduced to suppress abnormal discharge in the heat transfer gas supply hole 50a.

[0050] Furthermore, according to the first embodiment, the ceramic plate is an electrostatic chuck 113 having an electrode therein. As a result, abnormal discharge in the heat transfer gas supply holes 50a can be suppressed.

[0051] According to the first embodiment, the inner diameter of the heat transfer gas supply hole 50a in the ceramic plate is smaller than the inner diameter of the base (sleeve 51), and the upper surfaces of the second members 54, 54a, 54b are in contact with the lower surface of the ceramic plate so as to surround the outer periphery of the heat transfer gas supply hole 50a in the lower surface of the ceramic plate. As a result, abnormal discharge in the heat transfer gas supply hole 50a can be suppressed.

[0052] Furthermore, according to the first embodiment, the first members 53, 53a to 53c are arranged to have a gap between them and the inner wall of the heat transfer gas supply hole 50a. As a result, the heat transfer gas that has passed through the second members 54, 54a, 54b can be supplied to the supporting surface of the substrate support 11.

[0053] According to the first embodiment, the third members 55, 55a, and 55c are arranged to have a gap between them and the inner wall of the heat transfer gas supply hole 50a, so that the heat transfer gas can flow to the second members 54, 54a, and 54b.

[0054] According to the first embodiment, the heat transfer gas is supplied to the support surface through the gaps between the third members 55, 55a, 55c and the inner wall of the heat transfer gas supply hole 50a, the inside of the second members 54, 54a, 54b, and the gaps between the first members 53, 53a to 53c and the inner wall of the heat transfer gas supply hole 50a. As a result, abnormal discharge in the heat transfer gas supply hole 50a can be suppressed.

[0055] Furthermore, according to the first embodiment, the lower surface of the first member 53 contacts the upper surface of the second member 54, and the lower surface of the second member 54 contacts the upper surface of the third member 55. As a result, abnormal discharge in the heat transfer gas supply hole 50a can be suppressed.

[0056] According to the first modification, the lower part of the first member 53b penetrates the second member 54a and is fixed to the upper part of the third member 55a. As a result, the flow rate of the heat transfer gas can be increased while suppressing abnormal discharge in the heat transfer gas supply hole 50a.

[0057] Furthermore, according to the second modification, the lower portion of the first member 53c is fixed inside the second member 54b, which makes it possible to suppress abnormal discharge in the heat transfer gas supply hole 50a.

[0058] According to the first embodiment, the porous resin is PI, PTFE, PCTFE, PFA, PEEK, PEI, POM, MC, PC, or PPS. As a result, the heat transfer gas can be supplied to the support surface of the substrate support part 11 while suppressing abnormal discharge from the heat transfer gas supply hole 50a.

[0059] The embodiments disclosed herein should be considered to be illustrative and not restrictive in all respects. The above-described embodiments may be omitted, substituted, or modified in various forms without departing from the scope and spirit of the appended claims.

[0060] In addition, in each of the above-described embodiments, the capacitively coupled plasma processing apparatus 1 is used as an example to perform processing such as etching on the substrate W using capacitively coupled plasma as a plasma source, but the disclosed technology is not limited to this. As long as the apparatus performs processing on the substrate W using plasma, the plasma source is not limited to capacitively coupled plasma, and any plasma source such as inductively coupled plasma, microwave plasma, magnetron plasma, etc. can be used. [Explanation of symbols]

[0061] 1. Plasma processing equipment 2. Control section 10 Plasma Processing Chamber 11 Substrate support 20 Gas supply section 31 RF power supply 40 Exhaust system 50 Heat transfer gas supply path 50a Heat transfer gas supply hole 51 Sleeve 52,52a~52c Rod 53, 53a to 53c First member 54, 54a, 54b Second member 55, 55a, 55c Third member 59 Porous Materials 60 Heat transfer gas supply section 111a Board support surface 111b Ring support surface 113,113a Electrostatic chuck 114,114a,114b opening W substrate

Claims

1. A plasma treatment vessel; a substrate support portion disposed in the plasma processing chamber and having a support surface on an upper portion of a base, The substrate support includes: a heat transfer gas supply hole for supplying a heat transfer gas from the base side to the support surface; a first member made of silicon carbide and disposed in an opening of a ceramic plate provided on the support surface within the heat transfer gas supply hole; a second member made of a porous resin, the second member being disposed below the first member in the heat transfer gas supply hole so as to be in contact with the first member and the lower surface of the ceramic plate without any gap; and a third member arranged below the second member in the heat transfer gas supply hole and made of PTFE (polytetrafluoroethylene). Plasma processing equipment.

2. the second member is disposed so as to have no gap between itself and an inner wall of the heat transfer gas supply hole; The plasma processing apparatus according to claim 1 .

3. The first member has a length corresponding to at least the thickness of the ceramic plate.

3. The plasma processing apparatus according to claim 1 or 2.

4. The ceramic plate is an electrostatic chuck having an electrode therein. The plasma processing apparatus according to claim 3 .

5. The heat transfer gas supply hole is configured such that an inner diameter of the heat transfer gas supply hole in the ceramic plate is smaller than an inner diameter of the heat transfer gas supply hole in the base. an upper surface of the second member is in contact with a lower surface of the ceramic plate so as to surround an outer periphery of the heat transfer gas supply hole in the lower surface of the ceramic plate; 5. The plasma processing apparatus according to claim 3 or 4.

6. the first member is disposed so as to have a gap between itself and an inner wall of the heat transfer gas supply hole; 6. The plasma processing apparatus according to claim 1.

7. the third member is disposed so as to have a gap between itself and an inner wall of the heat transfer gas supply hole; 7. The plasma processing apparatus according to claim 1.

8. the heat transfer gas is supplied to the support surface through a gap between the third member and an inner wall of the heat transfer gas supply hole, an inside of the second member, and a gap between the first member and an inner wall of the heat transfer gas supply hole. The plasma processing apparatus according to claim 7 .

9. a lower surface of the first member contacts an upper surface of the second member; The lower surface of the second member is in contact with the upper surface of the third member.

9. The plasma processing apparatus according to claim 1.

10. A lower portion of the first member is fixed to an upper portion of the third member through the second member.

9. The plasma processing apparatus according to claim 1.

11. A lower portion of the first member is fixed inside the second member.

9. The plasma processing apparatus according to claim 1.

12. Porous resins include PI (polyimide), PTFE, PCTFE (polychlorotrifluoroethylene), PFA (perfluoroalkoxyalkane resin), PEEK (polyetheretherketone), PEI (polyetherimide), POM (polyoxymethylene, polyacetal, polyformaldehyde), and MC (methyl cellulose), PC (polycarbonate), or PPS (poly phenylene sulfone), The plasma processing apparatus according to any one of claims 1 to 11.

13. A substrate support disposed in a plasma processing chamber and having a support surface on an upper portion of a base, a heat transfer gas supply hole for supplying a heat transfer gas from the base side to the support surface; a first member made of silicon carbide and disposed in an opening of a ceramic plate provided on the support surface within the heat transfer gas supply hole; a second member made of a porous resin, the second member being disposed below the first member in the heat transfer gas supply hole so as to be in contact with the first member and the lower surface of the ceramic plate without any gap; and a third member arranged below the second member in the heat transfer gas supply hole and made of PTFE (polytetrafluoroethylene). Substrate support.

14. the second member is disposed so as to have no gap between itself and an inner wall of the heat transfer gas supply hole; The substrate support of claim 13.

15. The first member has a length corresponding to at least the thickness of the ceramic plate. A substrate support according to claim 13 or 14.

16. The ceramic plate is an electrostatic chuck having an electrode therein. The substrate support of claim 15.

17. The heat transfer gas supply hole is configured such that an inner diameter of the heat transfer gas supply hole in the ceramic plate is smaller than an inner diameter of the heat transfer gas supply hole in the base. an upper surface of the second member is in contact with a lower surface of the ceramic plate so as to surround an outer periphery of the heat transfer gas supply hole in the lower surface of the ceramic plate; A substrate support according to claim 15 or 16.

18. the first member is disposed so as to have a gap between itself and an inner wall of the heat transfer gas supply hole; A substrate support according to any one of claims 13 to 17.

19. the third member is disposed so as to have a gap between itself and an inner wall of the heat transfer gas supply hole; A substrate support according to any one of claims 13 to 18.

20. the heat transfer gas is supplied to the support surface through a gap between the third member and an inner wall of the heat transfer gas supply hole, an inside of the second member, and a gap between the first member and an inner wall of the heat transfer gas supply hole.

20. The substrate support of claim 19.

21. a lower surface of the first member contacts an upper surface of the second member; The lower surface of the second member is in contact with the upper surface of the third member. A substrate support according to any one of claims 13 to 20.

22. A lower portion of the first member is fixed to an upper portion of the third member through the second member. A substrate support according to any one of claims 13 to 20.

23. A lower portion of the first member is fixed inside the second member. A substrate support according to any one of claims 13 to 20.

24. Porous resins include PI (polyimide), PTFE, PCTFE (polychlorotrifluoroethylene), PFA (perfluoroalkoxyalkane resin), PEEK (polyetheretherketone), PEI (polyetherimide), POM (polyoxymethylene, polyacetal, polyformaldehyde), and MC (methyl cellulose), PC (polycarbonate), or PPS (poly phenylene sulfone), A substrate support according to any one of claims 13 to 23.

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