Plasma processing apparatus and electrode mechanism

Abstract

Provided is a plasma treatment device having a treatment chamber and an electrode mechanism used for a plasma treatment, wherein the electrode mechanism comprises: an electrode unit to which high-frequency power is applied; a dielectric unit disposed to be layered on the electrode unit; an electrical circuit at least a part of which is disposed inside the dielectric unit; and a shield member disposed inside the dielectric unit so as to be superposed with at least a part of the electrical circuit when viewed at least either in a plan view or a side view.

Description

[Technical field]

[0001] The present disclosure relates to a plasma processing apparatus and an electrode mechanism. [Background technology]

[0002] Patent Document 1 discloses a plasma processing apparatus having a heater power supply electrically connected via a heater power supply line to a heating element provided in a mounting table that supports an object to be processed, and in which high-frequency noise that enters the heater power supply line from the heating element toward the heater power supply is attenuated or blocked by a filter provided on the heater power supply line. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japan Patent Publication No. 2015-173027 Summary of the Invention [Problem to be solved by the invention]

[0004] The technology according to the present disclosure appropriately prevents high-frequency power from entering as a noise component into an electric circuit arranged in a plasma processing apparatus. [Means for solving the problem]

[0005] One aspect of the present disclosure is a plasma processing apparatus including a processing chamber and an electrode mechanism used for plasma processing, the electrode mechanism including: an electrode section to which high frequency power is applied; a dielectric section arranged in a stacked manner with the electrode section; an electric circuit at least a portion of which is arranged inside the dielectric section; and a shielding member arranged inside the dielectric section so as to overlap at least a portion of the electric circuit in at least one of a plan view and a side view. the electrode mechanism is a lower electrode mechanism used in plasma processing, and includes a substrate support that supports a substrate on a substrate support surface, the electrical circuit is a first heater electrode that heats the substrate supported on the substrate support surface, the shielding member is arranged to accommodate the first heater electrode integrally with the electrode portion, the shielding member includes a top plate member that is arranged along the surface direction of the dielectric portion, and a sidewall member that is arranged along the thickness direction of the dielectric portion and electrically connects the top plate member and the electrode portion, the top plate member is arranged between the first heater electrode and the substrate support surface inside the dielectric portion, and the distance between the first heater electrode and the top plate member is at least greater than the distance between the substrate support surface and the top plate member. Effect of the Invention

[0006] According to the present disclosure, it is possible to appropriately prevent high-frequency power from entering as a noise component into an electric circuit arranged in a plasma processing apparatus. [Brief description of the drawings]

[0007] [Figure 1] 1 is a vertical cross-sectional view showing a configuration example of a plasma processing system according to an embodiment of the present invention. [Diagram 2] 3 is a vertical cross-sectional view showing a configuration example of a substrate support according to the present embodiment. FIG. [Diagram 3] 13 is a vertical cross-sectional view showing an example of the configuration of a substrate support according to another embodiment. FIG. [Figure 4] 13 is a vertical cross-sectional view showing an example of the configuration of a substrate support according to another embodiment. FIG. [Diagram 5] FIG. 13 is an explanatory diagram showing the flow of high-frequency power in a conventional substrate support. [Figure 6] 5 is an explanatory diagram showing a flow of high-frequency power in the substrate support according to the embodiment; FIG. [Figure 7] 13 is a vertical cross-sectional view showing an example of the configuration of a substrate support according to another embodiment. FIG. [Figure 8] 13 is a vertical cross-sectional view showing an example of the configuration of a substrate support according to another embodiment. FIG. [Figure 9] 13 is a vertical cross-sectional view showing an example of the configuration of a substrate support according to another embodiment. FIG. [Figure 10] 13 is a vertical cross-sectional view showing an example of the configuration of a substrate support according to another embodiment. FIG. [Figure 11] 13 is a vertical cross-sectional view showing an example of the configuration of a substrate support according to another embodiment. FIG. [Figure 12] 13 is a vertical cross-sectional view showing an example of the configuration of a substrate support according to another embodiment. FIG. [Figure 13] 13 is a vertical cross-sectional view showing an example of the configuration of a substrate support according to another embodiment. FIG. [Figure 14] FIG. 2 is a vertical cross-sectional view showing a configuration example of an upper electrode mechanism according to one embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] In a manufacturing process of a semiconductor device, a processing gas supplied into a chamber is excited to generate plasma, and various plasma processes such as etching, film formation, and diffusion are performed on a semiconductor substrate (hereinafter simply referred to as "substrate") supported by a substrate support. The substrate support that supports the substrate is provided with, for example, an electrostatic chuck that attracts and holds the substrate on a mounting surface by Coulomb force or the like, and an electrode portion to which high-frequency power is applied during plasma processing.

[0009] In the above-mentioned plasma processing, in order to improve the uniformity of the process characteristics for the substrate, it is required to appropriately adjust the temperature distribution of the substrate to be processed. The temperature distribution of the substrate during the plasma processing is adjusted, for example, by providing a plurality of heating elements (e.g., heaters) inside the electrostatic chuck and controlling the temperature of the mounting surface for each of a plurality of temperature control regions defined by these heating elements. The plurality of heating elements arranged inside the electrostatic chuck are connected to a heating element power supply for supplying power to the heating elements via a corresponding power supply cable.

[0010] Incidentally, in a power supply cable connecting a heating element and a power supply for the heating element, a part of the high frequency applied to an electrode from an RF (Radio Frequency) power supply during plasma generation may enter as common mode noise (hereinafter simply referred to as "high frequency noise"), which may cause abnormal discharge or backflow of high frequency power. In particular, when the entered high frequency noise reaches the power supply for the heating element, it may cause damage or malfunction of the power supply for the heating element. For this reason, in plasma processing apparatuses, as disclosed in Patent Document 1, an RF cut filter (filter unit) for attenuating or blocking high frequency noise is arranged on the power supply cable (line).

[0011] In this way, in the plasma processing apparatus described in Patent Document 1, the RF cut filter is used to attenuate the high-frequency noise that has entered the power supply cable, but the high-frequency noise cannot be completely blocked, and there is a risk that some of the noise may reach the power supply for the heating element. If some of the high-frequency noise reaches the power supply for the heating element, as described above, there is a risk that the power supply for the heating element may be damaged or malfunction.

[0012] In addition, the RF cut filter arranged on the power supply cable acts as a resistor when high-frequency noise passes through, which may cause a loss of high-frequency power and reduce power efficiency. Furthermore, if there is variation in the resistance value of the RF cut filter arranged on the power supply cable, such variation in resistance value may appear as an individual difference between plasma processing apparatuses.

[0013] The technology disclosed herein has been made in consideration of the above circumstances, and appropriately suppresses high-frequency power from entering as a noise component into an electric circuit arranged in a plasma processing apparatus. Hereinafter, a plasma processing system including a plasma processing apparatus according to the present embodiment will be described with reference to the drawings. Note that in this specification and the drawings, elements having substantially the same functional configuration are denoted by the same reference numerals, and duplicated descriptions will be omitted.

[0014] <Plasma processing equipment> First, a plasma processing system according to the present embodiment will be described with reference to Fig. 1, which is a vertical cross-sectional view showing an outline of the configuration of the plasma processing system according to the present embodiment.

[0015] The plasma processing system includes a capacitively coupled plasma processing apparatus 1 and a control unit 2. The 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 11 and a gas introduction unit. The substrate support 11 is disposed inside the plasma processing chamber 10. 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 showerhead 13. The showerhead 13 is disposed above the substrate support 11. In one embodiment, the showerhead 13 constitutes at least a part of the ceiling of the plasma processing chamber 10. Inside the plasma processing chamber 10, a plasma processing space 10s defined by the showerhead 13, the side wall 10a of the plasma processing chamber 10, and the substrate support 11 is formed. 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 discharge port for discharging 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 plasma processing chamber 10.

[0016] The substrate support 11 includes a main body member 111 as an electrode mechanism and a ring assembly 112. The upper surface of the main body member 111 has a central region 111a (substrate support surface) for supporting a substrate (wafer) W and an annular region 111b (ring support surface) for supporting the ring assembly 112. The annular region 111b surrounds the central region 111a in a plan view. The ring assembly 112 includes one or more annular members, and at least one of the one or more annular members is an edge ring.

[0017] As shown in FIG. 2, in one embodiment, the main body member 111 includes a base 113 as an electrode part and an electrostatic chuck 114. The base 113 and the electrostatic chuck 114 are laminated and joined via an adhesive member G. In this embodiment, the electrostatic chuck 114 and the adhesive member G constituting the main body member 111 correspond to the "dielectric part" according to the technology of the present disclosure.

[0018] The base 113 is made of a conductive material such as an Al alloy. The conductive material of the base 113 functions as a lower electrode. A flow path C is formed inside the base 113. A heat transfer medium (temperature control fluid) is circulated through the flow path C from a chiller unit (not shown). By circulating the heat transfer medium through the flow path C, the ring assembly 112, an electrostatic chuck 114 (described below), and the substrate W are adjusted to desired temperatures. Note that a refrigerant such as cooling water can be used as the heat transfer medium.

[0019] The electrostatic chuck 114 is laminated and bonded to the upper surface of the base 113. The upper surface of the electrostatic chuck 114 has the above-mentioned central region 111a and annular region 111b. An attraction electrode 115, a heater electrode 116, and a shield member 120 are provided inside the electrostatic chuck 114. The electrostatic chuck 114 is configured by sandwiching the attraction electrode 115, the heater electrode 116, and the shield member 120 between a pair of dielectric films made of a nonmagnetic dielectric material such as ceramics.

[0020] The adsorption electrode 115 has a first adsorption electrode 115a for adsorbing and holding the substrate W in the central region 111a, and a second adsorption electrode 115b for adsorbing and holding the ring assembly 112 in the annular region 111b. The adsorption electrode 115 is connected to an adsorption power source (not shown), and applying a voltage from the adsorption power source to the adsorption electrode 115 generates an electrostatic force such as Coulomb force, and the substrate W is adsorbed and held on the electrostatic chuck 114 by the electrostatic force.

[0021] As the power supply for attraction, the power supply 30 shown in FIG. 1 and described later may be used, or a power supply for attraction (not shown) independent of the power supply 30 may be connected.

[0022] The heater electrode 116 as an electric circuit has one or more first heater electrodes 116a for heating the substrate W and one or more second heater electrodes 116b for heating the ring assembly 112. A heating power source 118 is connected to the heater electrode 116 via an RF cut filter 117. The heater electrode 116 generates heat when power is applied from the heating power source 118, and heats at least one of the ring assembly 112, the electrostatic chuck 114, and the substrate W.

[0023] When plasma is generated in the plasma processing space 10s, the RF cut filter 117 prevents the noise components from reaching the heating power supply 118 when the high-frequency power applied to the conductive member of the base 113 from the RF power supply 31 described below enters the heater electrode 116 as noise components.

[0024] The heating power supply 118 is configured to be able to individually control the supply of current to each of the multiple heater electrodes 116, for example, by the control unit 2 described later. In other words, the electrostatic chuck 114 is configured to be able to control the temperature of the central region 111a (substrate W) and the annular region 111b (ring assembly 112) for each of the multiple heater electrodes 116 or for each of multiple temperature control regions defined by a combination of the multiple heater electrodes 116 in a plan view. Note that the heating power supply 118 may be the power supply 30 shown in FIG. 1 described later, or a heating power supply 118 independent of the power supply 30 may be connected.

[0025] The shielding member 120 is made of, for example, a conductive metal material having a sufficiently low resistance value with respect to the high-frequency power applied to the conductive member of the base 113, that is, a conductive metal material (e.g., tungsten, titanium, etc.) that suppresses the transmission loss of the high-frequency power and attenuates or prevents the transmission of the high-frequency power.

[0026] The shield member 120 is provided inside the electrostatic chuck 114 so as to surround at least the periphery of the heater electrode 116. Specifically, in one embodiment, the shield member 120 includes a substantially disk-shaped first top plate member 121 arranged so as to cover the first heater electrode 116a in a plan view, a substantially ring-shaped second top plate member 122 arranged so as to cover the second heater electrode 116b in a plan view, a substantially cylindrical first side wall member 123 arranged so as to surround the first heater electrode 116a in a side view, and a substantially cylindrical second side wall member 124 arranged so as to surround the second heater electrode 116b in a side view. In other words, in one embodiment, the shield member 120 has a top plate member provided inside the electrostatic chuck 114 on the opposite side of the base 113 with respect to the heater electrode 116 in the stacking direction of the base 113 and the electrostatic chuck 114. The shield member 120 also has a side wall member provided inside the electrostatic chuck 114 on the radial outer side of the heater electrode 116.

[0027] More specifically, the first top plate member 121 is disposed between the first chucking electrode 115a and the first heater electrode 116a along the surface direction of the electrostatic chuck 114. The second top plate member 122 is disposed between the second chucking electrode 115b and the second heater electrode 116b along the surface direction. The first side wall member 123 is disposed along the stacking direction of the base 113 and the electrostatic chuck 114, i.e., the thickness direction of the electrostatic chuck 114, so as to electrically connect the first top plate member 121 and the second top plate member 122. The second side wall member 124 is disposed along the stacking direction (thickness direction) so as to electrically connect the second top plate member 122 and the base 113. That is, in one embodiment, the shield member 120 is disposed inside the electrostatic chuck 114 so as to be at approximately the same potential as the base 113.

[0028] In other words, in one embodiment, the heater electrode 116 arranged inside the electrostatic chuck 114 is arranged so as to be approximately contained inside the equipotential space S (see FIG. 2) defined by the base 113 and the shield member 120, which are arranged so as to be at approximately the same potential.

[0029] The first top plate member 121 and the second top plate member 122 arranged along the surface direction of the electrostatic chuck 114 are desirably arranged at positions closer to the chucking electrode 115 (more preferably, the surface of the electrostatic chuck 114) in the thickness direction of the electrostatic chuck 114 than the heater electrode 116. In other words, it is desirably to determine the position of the top plate member so that the distance between the heater electrode 116 and the top plate member is larger than the distance between the chucking electrode 115 (more preferably, the surface of the electrostatic chuck 114) and the top plate member. By bringing the top plate member of the shield member 120 closer to the surface of the electrostatic chuck 114 in this manner, the top plate member can play a role as a bias electrode during plasma processing, and power efficiency during plasma generation can be improved.

[0030] Although not shown, the substrate support 11 may include a heat transfer gas supply unit configured to supply a heat transfer gas (backside gas) between the back surface of the substrate W and the upper surface of the electrostatic chuck 114.

[0031] Returning to the explanation of Figure 1. 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 from the gas supply unit 20 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.

[0032] 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.

[0033] 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 at least one of a conductive member (lower electrode) of the substrate support 11 and a conductive member (upper electrode) 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, a bias potential is generated on the substrate W by supplying a bias RF signal to the lower electrode, and ion components in the formed plasma can be attracted to the substrate W.

[0034] 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 at least one of the lower electrode or the upper electrode 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 at least one of the lower electrode or the upper electrode. The second RF generating unit 31b is coupled to the lower electrode 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 generating unit 31b may be configured to generate a plurality of bias RF signals having different frequencies. The generated bias RF signal or signals are provided to the lower electrode, and in various embodiments, at least one of the source RF signal and the bias RF signal may be pulsed.

[0035] 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 the lower electrode and configured to generate a first DC signal. The generated first bias DC signal is applied to the lower electrode. In one embodiment, the first DC signal may be applied to another electrode, such as the attraction electrode 115 in the electrostatic chuck 114. In one embodiment, the second DC generator 32b is connected to the upper electrode and configured to generate a second DC signal. The generated second DC signal is applied to the upper electrode. In various embodiments, at least one of the first and second DC signals may be pulsed. It is noted that the first and second DC generators 32a, 32b may be provided in addition to the RF power supply 31, or the first DC generator 32a may be provided instead of the second RF generator 31b.

[0036] 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 regulating valve regulates the internal pressure of the plasma processing space 10s. The vacuum pump may include a turbomolecular pump, a dry pump, or a combination thereof.

[0037] 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).

[0038] Although various exemplary embodiments have been described above, the present invention is not limited to the above-described exemplary embodiments, and various additions, omissions, substitutions, and modifications may be made. In addition, elements in different embodiments can be combined to form other embodiments.

[0039] For example, in the present embodiment, the plasma processing system has a capacitively coupled plasma (CCP) type plasma processing apparatus 1, but the configuration of the plasma processing system is not limited to this. For example, the plasma processing system may have a processing apparatus including a plasma generating unit such as an inductively coupled plasma (ICP), an electron-cyclotron-resonance plasma (ECR plasma), a helicon wave plasma (HWP), or a surface wave plasma (SWP). In addition, processing apparatuses including various types of plasma generating units, including an alternating current (AC) plasma generating unit and a direct current (DC) plasma generating unit, may be used.

[0040] 2, the heater electrode 116 includes a first heater electrode 116a for heating the substrate W and a second heater electrode 116b for heating the ring assembly 112. However, in the heater electrode 116 disposed inside the electrostatic chuck 114, the second heater electrode 116b for heating the ring assembly 112 can be omitted as appropriate, as shown in FIG. In addition, in the case where the second heater electrode 116b is omitted in this manner, as shown in FIG. 4, the second top plate member 122 and the second side wall member 124 of the shield member 120 may be omitted, and the first top plate member 121 and the base 113 may be electrically connected by the first side wall member 123.

[0041] <Functions and Effects of the Substrate Support According to the Present Disclosure> As described above, in the substrate support 11 according to this embodiment, the shield member 120 made of a conductive metal material having a sufficiently low resistance value against high frequency power is disposed inside the electrostatic chuck 114 .

[0042] Here, the high frequency power applied to the conductive member of the base 113 during plasma processing propagates through the surface of the base 113, which is a conductive member, and is supplied to the plasma processing space. At this time, in the conventional substrate support 11' in which the shield member 120 is not arranged, as shown in FIG. 5, a part of the high frequency power propagating through the surface of the base 113 may enter the heater electrode 116 arranged in an electrically floating state inside the electrostatic chuck 114. More specifically, due to the potential difference between the base 113 and the heater electrode 116, a part of the high frequency power propagating through the surface of the base 113 may enter the heater electrode 116 as a noise component, and the potential difference may further increase, causing a discharge. The noise component that has entered the heater electrode 116 and the generated discharge may cause, for example, damage to the heater electrode 116 and the heating power source 118, or a decrease in power efficiency.

[0043] In this regard, in the substrate support 11 according to the present embodiment, a shield member 120 is provided inside the electrostatic chuck 114 so as to have substantially the same potential as the base 113. As a result, even when high-frequency power is applied to the conductive member of the base 113, the high-frequency power propagates through the surface of the shield member 120 instead of through the surface of the base 113, as shown in Fig. 6. This prevents the high-frequency power from propagating through the surface of the base 113 and reaching the vicinity of the heater electrode 116, thereby appropriately preventing the high-frequency power from penetrating into the heater electrode 116.

[0044] In this embodiment, as described above, the heater electrode 116, which is subject to the risk of intrusion of high-frequency power, is accommodated inside the equipotential space S defined by the base 113 and the shield member 120, which are arranged to have approximately the same potential. This prevents the occurrence of a potential difference between the heater electrode 116 and the base 113 inside the equipotential space S, thereby further appropriately preventing the intrusion of high-frequency power into the heater electrode 116.

[0045] Furthermore, according to this embodiment, the high-frequency power applied to the conductive member of the base 113 in this manner propagates through the surface of the shield member 120 and reaches the vicinity of the surface of the electrostatic chuck 114, i.e., the vicinity of the plasma processing space 10s, thereby improving the plasma generation efficiency during plasma processing. Furthermore, according to this embodiment, as described above, the first top plate member 121 and the second top plate member 122 are disposed closer to the attraction electrode 115 (the surface of the electrostatic chuck 114) than the heater electrode 116, thereby making it possible to further appropriately improve the plasma generation efficiency.

[0046] In the above embodiment, the substrate support 11 is described by taking as an example a case where the heater electrode 116 is accommodated in the equipotential space S defined by the base 113 and the shield member 120, which are arranged to have approximately the same potential. However, the configuration of the substrate support 11 is not limited to this, and any configuration may be used as long as it can at least attenuate or prevent the intrusion of high frequency power into the heater electrode 116.

[0047] Specifically, for example, instead of configuring the first top plate member 121 in a disk shape so as to completely cover the first heater electrode 116a in a plan view as shown in Fig. 2, the first top plate member 121 may be configured in a substantially annular shape so as to cover at least a part of the first heater electrode 116a in a plan view as shown in Fig. 7. In other words, the heater electrode 116 does not necessarily have to be disposed so as to be contained inside the equipotential space S. In this way, even when the first top plate member 121 is configured in a substantially annular shape, the high frequency power propagates through the surfaces of the second side wall member 124, the second top plate member 122, and the first side wall member 123 and reaches the vicinity of the surface of the electrostatic chuck 114, so that the penetration of the high frequency power into the first heater electrode 116a can be attenuated at least. Furthermore, by configuring the first top plate member 121 in this manner to have an approximately circular ring shape, the heat generated by the first heater electrode 116a can be transferred directly to the substrate W without passing through the first top plate member 121, thereby improving the heating efficiency of the substrate W by the first heater electrode 116a.

[0048] Furthermore, if the shield member 120 can allow the high frequency power to reach the vicinity of the surface of the electrostatic chuck 114, the first top plate member 121 may be omitted, as shown in Fig. 8. Even in this case, it is possible to at least attenuate the penetration of the high frequency power into the first heater electrode 116a, and to improve the heating efficiency of the substrate W by the first heater electrode 116a.

[0049] Furthermore, although not shown, both the first top plate member 121 and the second top plate member 122 of the shield member 120 may be omitted as long as the high frequency power can reach the vicinity of the surface of the electrostatic chuck 114. In other words, the shield member 120 may be formed of only the side wall member (the first side wall member 123 or the second side wall member 124). 2, when the heater electrode 116 includes the first heater electrode 116a and the second heater electrode 116b, the shield member 120 can be formed only from the second side wall member 124. When the heater electrode 116 includes only the first heater electrode 116a, as shown in FIG. 3, the shield member 120 can be formed only from the first side wall member 123. Even in such a case, by positioning the upper end portion of the shield member 120 (the first side wall member 123 or the second side wall member 124) at least above the heater electrode 116, more preferably near the surface of the electrostatic chuck 114, the penetration of high-frequency power into the first heater electrode 116a can be at least attenuated.

[0050] As described above, the high frequency power applied to the conductive member of the base 113 propagates through the surfaces of the base 113 and the shield member 120 to reach the vicinity of the surface of the electrostatic chuck 114, i.e., for example, the first top plate member 121. However, at this time, if at least a part of the first top plate member 121 is omitted as shown in Fig. 7 and Fig. 8, the supply of high frequency power to the plasma processing space 10s may be biased, which may result in biased uniformity in the plasma processing result for the substrate W.

[0051] Therefore, from the viewpoint of improving the uniformity of the plasma processing results for the substrate W, it is preferable that the shield member 120 (specifically, the first top plate member 121 and the second top plate member 122) be arranged so as to uniformly cover the entire surface of the electrostatic chuck 114 in a planar view.

[0052] In general, the electrostatic chuck 114 for holding the substrate W is configured to have a sufficiently large radial size compared to the thickness size. Specifically, for example, the radial size of the electrostatic chuck 114 is about 300 mm or more in accordance with the size of the substrate W, whereas the thickness size of the electrostatic chuck 114 is about 10 mm or less. For this reason, in the electrostatic chuck 114 according to the present embodiment, when the shield member 120 is disposed inside the electrostatic chuck 114, the installation position and thickness of the shield member 120 are changed to perform impedance design, so that the high-frequency power propagating through the surface of the base 113 can be propagated to the surface of the top plate member (the first top plate member 121 or the second top plate member 122). In other words, by appropriately performing impedance design, even if the side wall member (the first side wall member 123 or the second side wall member 124) of the shield member 120 is omitted as shown in FIG. 9, the penetration of the high-frequency power into the first heater electrode 116a can be attenuated. In other words, the shield member 120 does not necessarily have to be arranged so as to have approximately the same potential as the base 113. By arranging the first top plate member 121 in particular as the shield member 120 in this manner, it is possible to propagate high-frequency power over the entire surface of the first top plate member 121 (electrostatic chuck 114) in a plan view, and as a result, it is possible to improve the uniformity of the plasma processing result for the substrate W.

[0053] In the above embodiment, in order to appropriately suppress the intrusion of high frequency power into the heater electrode 116, the first top plate member 121 and the second top plate member 122 of the shield member 120 are each formed of a plate-like member having no holes. Similarly, the first side wall member 123 and the second side wall member 124 are each formed of a plate-like member having no holes, whereby the base 113 and the shield member 120 are in line contact so as to surround the entire periphery of the heater electrode 116. However, the configuration of the shield member 120 is not limited to this as long as it can at least attenuate the intrusion of high frequency power into the heater electrode 116.

[0054] Specifically, for example, the sidewall member of the shield member 120 may be formed in a lattice (mesh) shape as shown in FIG. 10. In other words, one or more holes may be formed in the top plate member and the sidewall member of the shield member 120. Even in such a case, the high frequency power propagating on the surface of the base 113 can be propagated along the surface of the shield member 120, that is, the amount of high frequency power propagating near the heater electrode 116 can be attenuated, and as a result, the intrusion of the high frequency power into the heater electrode 116 can be suppressed. Also, even in the case where the first top plate member 121 is formed in a lattice shape in this way, the high frequency power can be propagated over the entire surface of the first top plate member 121 (electrostatic chuck 114) in a plan view, and as a result, the uniformity of the plasma processing result for the substrate W can be improved.

[0055] Similarly, as shown in FIG. 11, by forming the sidewall members of the shield member 120 in a vertical lattice pattern, the amount of high-frequency power propagating at least to the vicinity of the heater electrode 116 can be attenuated, and as a result, the intrusion of high-frequency power into the heater electrode 116 can be suppressed.

[0056] 10 and 11, the side wall member of the shield member 120 is configured in a lattice or vertical lattice shape, but the top plate member of the shield member 120 may be configured in a lattice or vertical lattice shape. Even when the top plate member is configured in a lattice or vertical lattice shape in this manner, high-frequency power can be propagated over the entire surface of the electrostatic chuck 114 in a plan view, and as a result, the uniformity of the plasma processing result for the substrate W can be improved.

[0057] In addition, as shown in Figures 10 and 11, when the shield member 120 and the base 113 are in point contact at multiple points instead of in line contact around the entire circumference, if the contact points are not uniformly arranged around the heater electrode 116, there is a risk that the plasma processing results will be biased or that the shield member 120 and the base 113 will not be able to be appropriately configured to have approximately the same potential. Therefore, in the case where the shield member 120 and the base 113 are brought into point contact in this manner, it is desirable to arrange such contact points evenly all around the circumference of the electrostatic chuck 114. Specifically, for example, in the case where the contact points are designed to be six, it is desirable to arrange the contact points every 60 degrees in the circumferential direction. Furthermore, when the shielding member 120 and the base 113 are brought into point contact in this manner, it is desirable to increase the number of such contact points as much as possible in order to properly configure the shielding member 120 and the base 113 at the same potential.

[0058] In the above embodiment, the heater electrode 116 includes the first heater electrode 116a and the second heater electrode 116b, and the first heater electrode 116a and the second heater electrode 116b are integrally accommodated in the same potential space S by one shield member 120. However, the first heater electrode 116a and the second heater electrode 116b may be independently accommodated in the same potential space S. In other words, a plurality of shield members 120 may be disposed inside the electrostatic chuck 114 to form a plurality of same potential spaces S, and the first heater electrode 116a and the second heater electrode 116b may be disposed in each of the plurality of same potential spaces S.

[0059] In the above embodiment, an example has been described in which the heater electrode 116 as an electric circuit is disposed inside the electrostatic chuck 114. However, the heater electrode 116 may be disposed so that at least a portion of the heater electrode 116 is in contact with the dielectric portion.

[0060] Specifically, in one embodiment, the heater electrode 116 may be disposed inside the electrostatic chuck 114 or the adhesive member G as the dielectric part, or may be disposed so as to straddle the space between the electrostatic chuck 114 and the adhesive member G. In addition, in one embodiment, as long as the heater electrode 116 is in contact with the electrostatic chuck 114 or the adhesive member G as the dielectric part, one surface of the heater electrode 116 may be in contact with the base 113 as shown in FIG. 12, or a portion of the heater electrode 116 may be embedded in the base 113 as shown in FIG. 13.

[0061] In the substrate support 11 according to this embodiment, as described above, an RF cut filter 117 for attenuating or blocking high frequency power is provided on the power supply cable connecting the heater electrode 116 and the heating power supply 118. This makes it possible to appropriately prevent noise components from reaching the heating power supply 118 even if the shield member 120 cannot completely prevent the high frequency power from entering the heater electrode 116. In particular, in this embodiment, the amount of high frequency power entering the heater electrode 116 is attenuated by the action of the shield member 120, so that the heating power source 118 can be more easily protected by the RF cut filter 117.

[0062] In other words, in this embodiment, the high frequency power entering the heater electrode 116 can be attenuated or blocked only by the action of the shield member 120. Therefore, in the substrate support 11 according to this embodiment, the RF cut filter 117 disposed on the power supply cable can be appropriately downsized or omitted.

[0063] Generally, a plurality of RF cut filters 117 must be provided in the space below the substrate support 11 (electrostatic chuck 114) corresponding to each of the plurality of heater electrodes 116 or each of the plurality of temperature control regions defined by a combination of the heater electrodes 116. That is, it is necessary to dispose a plurality of RF cut filters 117 and power supply cables for connecting them in the space below the substrate support 11, which may occupy the space below the substrate support 11.

[0064] In this regard, according to the present embodiment, the RF cut filter 117 can be reduced in size or omitted as described above by providing the shield member 120 inside the electrostatic chuck 114. As a result, the power supply cable and the RF cut filter 117 arranged in the lower space of the substrate support 11 (electrostatic chuck 114) can be reduced, the space efficiency of the lower space can be improved, and the cost of installing the substrate support 11 can be reduced.

[0065] Furthermore, in the conventional substrate support 11, the high frequency power that entered the heater electrode 116 as a noise component was wasted when passing through the RF cut filter 117, i.e., the RF cut filter 117 acted as a resistor, which sometimes reduced the power efficiency. In addition, in this case, particularly when the resistance value of the RF cut filter 117 varies, such variation in the resistance value may appear as an individual difference in the plasma processing apparatus 1. In this regard, according to the present embodiment, the installation of the RF cut filter 117 can be omitted in this manner, so that the power loss due to the RF cut filter 117 can be suppressed and the power efficiency can be improved, and the problem of machine differences caused by the RF cut filter 117 can be improved.

[0066] In the above embodiment, an example has been described in which the shield member 120 for suppressing or preventing intrusion of high frequency power into the electric circuit is disposed inside the electrostatic chuck 114, or more broadly, inside the substrate support 11 constituting the lower electrode mechanism. However, the installation position of the shield member according to the technology of the present disclosure is not limited thereto, and the shield member may be disposed in any member that includes an electric circuit inside which intrusion of high frequency power should be suppressed.

[0067] Specifically, for example, in the case where an upper electrode mechanism in the plasma processing apparatus 1 includes an electric circuit therein instead of inside the lower electrode mechanism, the shield member may be disposed inside the upper electrode mechanism.

[0068] Fig. 14 is a cross-sectional view showing an outline of the configuration of the upper electrode mechanism 130 according to one embodiment. As shown in Fig. 14, in one embodiment, the upper electrode mechanism 130 includes a metal plate 131 and a shower head 132 as electrode parts. The metal plate 131 and the shower head 132 are laminated via an adhesive member G. Note that in this embodiment, the shower head 132 and adhesive member G constituting the upper electrode mechanism 130 correspond to the "dielectric part" according to the technology of the present disclosure.

[0069] The metal plate 131 is made of a conductive material such as an Al alloy. The conductive material of the metal plate 131 functions as an upper electrode. A gas supply port 13a and a gas diffusion chamber 13b are formed inside the metal plate 131. The metal plate 131 also has at least one flow path C therein for controlling the temperature of the shower head 132, the temperature of which varies due to the heat input of plasma. A heat transfer medium (temperature control fluid) is circulated and supplied to the flow path C from a chiller unit (not shown).

[0070] The shower head 132 has a plurality of gas inlets 13c formed therethrough in the thickness direction (vertical direction). The gas inlets 13c are connected to the gas supply unit 20 via the gas diffusion chamber 13b and the gas supply port 13a formed inside the metal plate 131, and are configured to introduce at least one processing gas from the gas supply unit 20 into the plasma processing space 10s. The shower head 132 also has at least one heater electrode 140 therein for controlling the temperature of the shower head 132, which varies due to the heat input of the plasma. In this embodiment, the heater electrode 140 corresponds to the "electrical circuit" according to the technology of the present disclosure.

[0071] In one embodiment, a shield member 150 is disposed inside the upper electrode mechanism 130, more specifically, inside the shower head 132, for attenuating or preventing the intrusion of high-frequency power applied to the conductive member (upper electrode) of the metal plate 131 into the heater electrode 140. The shield member 150 is made of, for example, a conductive metal material (e.g., tungsten, titanium, etc.) having a sufficiently low resistance value with respect to the high-frequency power applied to the upper electrode. In one embodiment, the shield member 150 is disposed inside the shower head 132 so as to surround at least the periphery of the heater electrode 140 and to have the same potential as the metal plate 131. In other words, in one embodiment, the upper electrode mechanism 130 accommodates the heater electrode 140, which is a concern due to the intrusion of high-frequency power, inside an equipotential space S defined by the metal plate 131 and the shield member 120, which are disposed so as to have approximately the same potential.

[0072] In the upper electrode mechanism 130 according to one embodiment, by disposing the shield member 150 inside the shower head 132 in this manner, the high frequency power applied to the upper electrode propagates through the surfaces of the metal plate 131 and the shield member 150 and reaches the vicinity of the surface of the shower head 132, i.e., the vicinity of the plasma processing space 10s. As a result, the high frequency power can be appropriately prevented from entering the heater electrode 140.

[0073] The configuration of the shield member 150 disposed inside the shower head 132 is not limited to the illustrated example. That is, like the shield member 120 disposed inside the electrostatic chuck 114, either the top plate member or the side wall member constituting the shield member 150 may be omitted, or the top plate member or the side wall member may be configured in a lattice shape or a vertical lattice shape.

[0074] Furthermore, the arrangement of the heater electrode 140 as an electric circuit is not limited to the example shown in the figure, and it is sufficient that the heater electrode 140 is arranged so that at least a portion of the heater electrode 140 is in contact with the dielectric portion. Specifically, in one embodiment, the heater electrode 140 may be disposed inside the adhesive member G, or may be disposed so as to straddle between the shower head 132 and the adhesive member G, as long as the heater electrode 140 is disposed inside the adhesive member G or the shower head 132 serving as a dielectric portion. In addition, in one embodiment, the heater electrode 140 may have one surface in contact with the metal plate 131, or a portion of the heater electrode 140 may be embedded in the metal plate 131, as long as the heater electrode 140 is in contact with the shower head 132 or the adhesive member G as a dielectric portion.

[0075] In this way, the shielding member according to the technology of the present disclosure is not limited to being placed inside the electrostatic chuck 114 of the lower electrode mechanism, but may be placed inside any component that has an electrical circuit therein that should prevent the intrusion of high-frequency power.

[0076] In the above embodiment, the electric circuit to be protected by suppressing the intrusion of high frequency power is a heater electrode, but the type of the electric circuit is not limited to this. For example, the shielding member can be disposed to protect any electric circuit that may be malfunctioned by the intrusion of high frequency power, such as a thermocouple, a piezoelectric element, or the drive mechanism of each part.

[0077] The embodiments disclosed herein should be considered as 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. [Explanation of symbols]

[0078] 1. Plasma processing equipment 10 Plasma Processing Chamber 11 Substrate support 113 Foundation 114 Electrostatic Chuck 120 Shielding material

Claims

1. A plasma processing apparatus comprising: A processing chamber; an electrode mechanism for use in plasma processing; The electrode mechanism includes: An electrode portion to which high frequency power is applied; a dielectric portion arranged to be laminated with the electrode portion; an electric circuit at least a portion of which is disposed inside the dielectric portion; a shielding member disposed inside the dielectric portion so as to overlap at least a portion of the electric circuit in at least one of a plan view and a side view, The electrode mechanism is a lower electrode mechanism used in plasma processing, and includes a substrate support that supports a substrate on a substrate support surface; the electrical circuit is a first heater electrode that heats the substrate supported on the substrate support surface; the shield member is disposed to accommodate the first heater electrode integrally with the electrode portion, The shield member is a top plate member disposed along a surface direction of the dielectric portion; a sidewall member disposed along a thickness direction of the dielectric portion and electrically connecting the top plate member and the electrode portion, a top plate member disposed inside the dielectric portion between the first heater electrode and the substrate support surface, and a distance between the first heater electrode and the top plate member is greater than at least a distance between the substrate support surface and the top plate member.

2. The plasma processing apparatus according to claim 1 , wherein the sidewall member is disposed in line contact with the electrode portion so as to completely surround the first heater electrode.

3. 2 . The plasma processing apparatus according to claim 1 , wherein the sidewall member is disposed in point contact with the electrode portion at a plurality of points in a circumferential direction of the electrode portion so as to completely surround the first heater electrode.

4. The plasma processing apparatus according to claim 3 , wherein a plurality of contact points between the electrode portion and the sidewall member are disposed at equal intervals in a circumferential direction of the electrode portion.

5. the substrate support includes a ring support surface that supports an edge ring; the electrical circuit includes a second heater electrode for heating the edge ring supported by the ring support surface; The plasma processing apparatus of claim 1 , wherein the shield member is disposed so as to integrally house the first heater electrode and the second heater electrode.

6. the substrate support includes a ring support surface that supports an edge ring; the electrical circuit includes a second heater electrode for heating the edge ring supported by the ring support surface; The plasma processing apparatus according to claim 1 , wherein the shield member is disposed so as to accommodate the first heater electrode and the second heater electrode independently of each other.

7. A plasma processing apparatus comprising: A processing chamber; an electrode mechanism for use in plasma processing; The electrode mechanism includes: An electrode portion to which high frequency power is applied; a dielectric portion arranged to be laminated with the electrode portion; an electric circuit at least a portion of which is disposed inside the dielectric portion; a shielding member disposed inside the dielectric portion so as to overlap at least a portion of the electric circuit in at least one of a plan view and a side view, the electrode mechanism is an upper electrode mechanism used in plasma processing, and includes a shower head for supplying a processing gas to a processing space in which a substrate is accommodated during the plasma processing; the electric circuit is a heater electrode that heats the shower head; The shield member is disposed so as to house the heater electrode integrally with the electrode portion.

8. 8. The plasma processing apparatus according to claim 1, wherein the shield member is disposed so as to have the same potential as the electrode portion.

9. 8. The plasma processing apparatus according to claim 1, wherein the shielding member at least attenuates passage of the high frequency power applied to the electrode portion.

10. 8. The plasma processing apparatus according to claim 1, wherein the shield member is made of a material selected from the group consisting of tungsten and titanium.

11. 9. The plasma processing apparatus according to claim 8, wherein the shield member is made of a material selected from the group consisting of tungsten and titanium.

12. An electrode mechanism for use in plasma processing, comprising: an electrode portion to which high frequency power is applied during the plasma processing; a dielectric portion arranged to be laminated with the electrode portion; a heater electrode at least a portion of which is disposed inside the dielectric portion and which heats the dielectric portion; a shield member disposed inside the dielectric portion so as to accommodate the heater electrode integrally with the electrode portion, The high frequency power applied to the electrode portion is propagated through an outer surface of the shielding member, The electrode mechanism is a lower electrode mechanism used in plasma processing, and includes a substrate support that supports a substrate on a substrate support surface; the heater electrode heats the substrate supported on the substrate support surface; The shield member is a top plate member disposed along a surface direction of the dielectric portion; a sidewall member disposed along a thickness direction of the dielectric portion and electrically connecting the top plate member and the electrode portion, An electrode mechanism, wherein the top plate member is disposed between the heater electrode and the substrate support surface inside the dielectric portion, and the distance between the heater electrode and the top plate member is greater than at least the distance between the substrate support surface and the top plate member.

13. An electrode mechanism for use in plasma processing, comprising: an electrode portion to which high frequency power is applied during the plasma processing; a dielectric portion arranged to be laminated with the electrode portion; a heater electrode at least a portion of which is disposed inside the dielectric portion and which heats the dielectric portion; a shield member disposed inside the dielectric portion so as to accommodate the heater electrode integrally with the electrode portion, The high frequency power applied to the electrode portion is propagated through an outer surface of the shielding member, the electrode mechanism is an upper electrode mechanism used in plasma processing, and includes a shower head for supplying a processing gas to a processing space in which a substrate is accommodated during the plasma processing; The heater electrode heats the showerhead.

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