Plasma treatment unit

Abstract

The present invention is a plasma processing apparatus having a processing chamber and an electrode mechanism for plasma processing; the electrode mechanism having an electrode portion to which radio frequency power is applied, a dielectric portion stacked with the electrode portion, a circuit at least a portion disposed inside the dielectric portion, and a shielding member disposed inside the dielectric portion such that it overlaps with at least a portion of the circuit in at least one of the views from above or from the side.

Description

[Technical Field]

[0001] This disclosure relates to plasma processing apparatus and electrode mechanism. [Previous Technology]

[0002] Patent Document 1 discloses a plasma processing apparatus having a heater power supply electrically connected to a heating element disposed in a platform supporting the object to be processed via a heater power supply line, wherein a filter disposed on the heater power supply line attenuates or blocks radio frequency noise entering the heater power supply line from the heating element toward the heater power supply line. [Prior Art Documents] [Patent Documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2015-173027 [Summary of the Invention]

[0004] [The problem the invention aims to solve]

[0005] The technology disclosed herein appropriately suppresses the intrusion of radio frequency power into the circuitry of a plasma processing device as noise components. [Means of Problem Solving]

[0006] One aspect of this disclosure is a plasma processing apparatus, comprising a processing chamber and an electrode mechanism for plasma processing; the electrode mechanism comprises an electrode portion to which radio frequency power is applied, a dielectric portion stacked with the electrode portion, a circuit at least partially disposed within the dielectric portion, and a shielding member disposed within the dielectric portion such that it overlaps with at least a portion of the circuit in at least one of top or side views. [Effects of the Invention]

[0007] According to this disclosure, radio frequency power can be appropriately suppressed to prevent noise components from interfering with circuits configured in plasma processing devices.

Implementation Method

[0009] [Form used to implement the invention]

[0010] In the manufacturing process of semiconductor devices, plasma is generated by excitation of the processing gas supplied to the chamber, and various plasma treatments such as etching, film formation, and diffusion are performed on the semiconductor substrate (hereinafter referred to as "substrate") supported on the substrate support. The substrate support supporting the substrate is provided with an electrostatic chuck that holds the substrate on the mounting surface by means of, for example, Coulomb force, and an electrode part that is subjected to radio frequency power during plasma treatment.

[0011] In the above-described plasma processing, in order to improve the uniformity of the process characteristics of the substrate, it is required to appropriately adjust the temperature distribution of the substrate to be processed. During plasma processing, the temperature distribution of the substrate is adjusted, for example, by using a plurality of heating elements (e.g., heaters) inside an electrostatic chuck, and controlling the temperature of the mounting surface according to each of the plurality of temperature adjustment zones defined by these heating elements. The plurality of heating elements disposed inside the electrostatic chuck are connected to a power supply for supplying power to the heating element via their respective power cables.

[0012] In some cases, the aforementioned situation occurs because a portion of the radio frequency applied from the RF (Radio Frequency) power supply to the electrode section during plasma generation, as common-mode noise (hereinafter simply referred to as "RF noise"), intrudes into the power supply cable connecting the heating element and the power supply for the heating element, resulting in abnormal discharge or reverse current of the radio frequency power. Furthermore, in particular, when the intruding RF noise reaches the power supply for the heating element, there is a risk of damage or malfunction of the power supply for the heating element. Therefore, in plasma processing apparatuses, as disclosed in Patent Document 1, a technique has been implemented in which an RF cutoff filter (filter unit) for attenuating or blocking RF noise is disposed on the power supply cable (line).

[0013] Thus, in the plasma processing apparatus described in Patent Document 1, although an RF cutoff filter is used to attenuate radio frequency noise intruding into the power supply cable, it is impossible to completely block the radio frequency noise, and there is a risk that a portion of it may reach the power supply for the heating element. Furthermore, when a portion of such radio frequency noise reaches the power supply for the heating element, as described above, there is a risk of damage or malfunction to the power supply for the heating element.

[0014] Furthermore, since the RF cutoff filter configured on the power supply cable acts as a resistor when radio frequency noise passes through, radio frequency power loss occurs, which may reduce power efficiency. Moreover, when the resistance value of the RF cutoff filter configured on the power supply cable deviates, this deviation may also become a mechanical defect in the plasma processing device.

[0015] The technology disclosed herein is made in view of the above circumstances, and appropriately suppresses the intrusion of radio frequency power into the circuitry of the plasma processing apparatus as noise components. Hereinafter, a plasma processing system having the plasma processing apparatus of this embodiment will be described with reference to the drawings. Furthermore, in this specification and drawings, elements having substantially the same functional structure are omitted from repeated description by using the same reference numerals.

[0016] <Plasma Treatment Apparatus> First, the plasma treatment system of this embodiment will be described. Figure 1 is a longitudinal cross-sectional view showing the structural outline of the plasma treatment system of this embodiment.

[0017] 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 unit 30, and an exhaust system 40. Furthermore, the plasma processing apparatus 1 includes a substrate support 11 and a gas inlet unit. The substrate support 11 is disposed within the plasma processing chamber 10. The gas inlet unit is configured to introduce at least one processing gas into the plasma processing chamber 10. The gas inlet unit includes a spray head 13. The spray head 13 is disposed above the substrate support 11. In one embodiment, the spray head 13 constitutes at least a portion of the ceiling of the plasma processing chamber 10. A plasma processing space 10s defined by the spray head 13, the sidewall 10a of the plasma processing chamber 10, and the substrate support 11 is formed inside the plasma processing chamber 10. 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 outlet for discharging gas from the plasma processing space 10s. The plasma processing chamber 10 is grounded. The spray head 13 and the substrate support 11 are electrically insulated from the plasma processing chamber 10s.

[0018] The substrate support 11 includes a body member 111 and a ring assembly 112 serving as an electrode mechanism. The body member 111 has a central region 111a (substrate support surface) for supporting the 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 when viewed from above. The ring assembly 112 includes one or more annular members, at least one of which is an edge ring.

[0019] As shown in FIG2, in one embodiment, the body member 111 includes a base 113 serving as an electrode portion and an electrostatic chuck 114. The base 113 and the electrostatic chuck 114 are laminated together by a bonding member G. Furthermore, in this embodiment, the electrostatic chuck 114 constituting the body member 111 and the bonding member G are equivalent to the "dielectric portion" of the disclosed technology.

[0020] The base 113 is constructed of a conductive component, such as an Al alloy. The conductive component of the base 113 functions as a lower electrode. Furthermore, a flow path C is formed inside the base 113. A heat transfer medium (temperature regulating fluid) from a cooling unit (not shown) is circulated and supplied to the flow path C. Then, by circulating the heat transfer medium in the flow path C, the ring assembly 112, the electrostatic chuck 114 (described later), and the substrate W are adjusted to the desired temperature. In addition, a refrigerant such as cooling water can be used as the heat transfer medium.

[0021] An electrostatic chuck 114 is laminated and bonded to the top of the base 113. The electrostatic chuck 114 has the aforementioned central region 111a and an annular region 111b. An adsorption electrode 115, a heating electrode 116, and a shielding member 120 are provided inside the electrostatic chuck 114. The electrostatic chuck 114 is constructed by sandwiching the adsorption electrode 115, the heating electrode 116, and the shielding member 120 between a pair of dielectric films made of a non-magnetic dielectric material such as ceramic.

[0022] 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 in the figure). A voltage is applied to the adsorption electrode 115 by the adsorption power source to generate electrostatic forces such as Coulomb force, and the substrate W is adsorbed and held on the electrostatic chuck 114 by the electrostatic force.

[0023] In addition, the power supply for adsorption can be the power supply 30 shown in Figure 1 (described later), or it can be connected to an adsorption power supply that is separate from the power supply 30 (not shown in the figure).

[0024] The heating electrode 116, which serves as a circuit, has one or more first heating electrodes 116a for heating the substrate W and one or more second heating electrodes 116b for heating the ring assembly 112. A heating power supply 118 is connected to the heating electrode 116 via an RF cutoff filter 117. The heating electrode 116 heats up by being powered by the heating power supply 118, thereby heating at least one of the ring assembly 112, the electrostatic chuck 114, and the substrate W.

[0025] When plasma is generated in the plasma processing space for 10 seconds, the RF cutoff filter 117 suppresses the noise component from entering the heating electrode 116 when the radio frequency power applied by the RF power supply 31 to the conductive component of the base 113 with noise components enters the heating power supply 118.

[0026] The heating power supply 118 is configured to individually control the energization of each of the plurality of heating electrodes 116, for example, as described later by the control unit 2. In other words, the electrostatic chuck 114 is configured such that, when viewed from above, the temperature of the central region 111a (substrate W) and the annular region 111b (ring assembly 112) can be controlled according to the plurality of temperature adjustment regions defined by each or a combination of the plurality of heating electrodes 116. Furthermore, the heating power supply 118 can use the power supply 30 shown later in FIG. 1, or it can be connected to a heating power supply 118 that is separate from and independent of the power supply 30.

[0027] The shielding member 120 is made of a conductive material with a relatively low resistance value to the radio frequency power applied to the conductive member of the base 113, that is, a conductive metal material (such as tungsten or titanium) that suppresses the transmission loss of radio frequency power and attenuates or blocks the passage of radio frequency power.

[0028] The shielding member 120 is disposed inside the electrostatic chuck 114 in such a way as to at least surround the heating electrode 116. Specifically, in one embodiment, the shielding member 120 includes a first top plate member 121 configured to cover the first heating electrode 116a in a generally circular plate shape when viewed from above, a second top plate member 122 configured to cover the second heating electrode 116b in a generally annular shape when viewed from above, a first sidewall member 123 configured to surround the first heating electrode 116a in a generally cylindrical shape when viewed from the side, and a second sidewall member 124 configured to surround the second heating electrode 116b in a generally cylindrical shape when viewed from the side. In other words, in one embodiment, the shielding member 120 has a top plate member disposed inside the electrostatic chuck 114, in the stacking direction of the base 113 and the electrostatic chuck 114, on the side opposite to the heating electrode 116 on the base 113. Furthermore, the shielding member 120 has a sidewall member located inside the electrostatic chuck 114 and radially outward from the heating electrode 116.

[0029] More specifically, the first top plate member 121 is disposed between the first adsorption electrode 115a and the first heating electrode 116a, along the surface direction of the electrostatic chuck 114. The second top plate member 122 is disposed between the second adsorption electrode 115b and the second heating electrode 116b, along the surface direction. The first sidewall 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, to electrically connect the first top plate member 121 and the second top plate member 122. The second sidewall member 124 is disposed along the stacking direction (thickness direction) to electrically connect the second top plate member 122 and the base 113. That is, in one embodiment, the shielding member 120 is disposed inside the electrostatic chuck 114 at approximately the same potential as the base 113.

[0030] In other words, in one embodiment, the heating electrode 116 disposed inside the electrostatic chuck 114 is configured to be approximately housed within the same potential space S (see Figure 2) defined by the base 113 and the shielding member 120 configured to be approximately at the same potential.

[0031] Furthermore, the first top plate member 121 and the second top plate member 122, arranged along the surface direction of the electrostatic chuck 114, are ideally positioned in the thickness direction of the electrostatic chuck 114 at a position closer to the adsorption electrode 115 (more preferably the surface of the electrostatic chuck 114) than the heating electrode 116. In other words, it is ideal to position the top plate members such that the distance between the heating electrode 116 and the top plate member is greater than the distance between the adsorption electrode 115 (more preferably the surface of the electrostatic chuck 114) and the top plate member. Thus, by placing the top plate member of the shielding member 120 close to the surface of the electrostatic chuck 114, the top plate member can function as a bias electrode during plasma processing, thereby improving the power efficiency during plasma generation.

[0032] In addition, although the illustration is omitted, the substrate support 11 may also include a heat transfer gas supply section configured to supply heat transfer gas (back gas) between the back side of the substrate W and the top side of the electrostatic chuck 114.

[0033] Returning to the description of Figure 1. The spray head 13 is configured to introduce at least one processing gas from the gas supply unit 20 into the plasma processing space 10s. The spray head 13 has at least one gas supply port 13a, at least one gas diffusion chamber 13b, and a plurality of 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 through the plurality of gas inlets 13c. Furthermore, the spray head 13 includes a conductive member. The conductive member of the spray head 13 functions as an upper electrode. In addition, the gas inlet unit, besides the spray head 13, may also include one or more side gas injectors (SGIs) installed in one or more openings formed on the sidewall 10a.

[0034] The gas supply unit 20 may also include at least one gas source 21 and at least one flow controller 22. In one embodiment, the gas supply unit 20 is configured to supply at least one treatment gas from its respective gas source 21 to the spray head 13 via its respective flow controller 22. Each flow controller 22 may also include, for example, a mass flow controller or a pressure-controlled flow controller. Furthermore, the gas supply unit 20 may also include one or more flow modulation elements for modulating or pulsed flow of at least one treatment gas.

[0035] The power supply 30 includes an RF power supply 31 connected to the plasma processing chamber 10 via at least one impedance matching circuit. The RF power supply 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 the conductive members (lower electrode) of the substrate support 11 or the conductive members (upper electrode) of the spray head 13. Plasma is thus formed from at least one processing gas supplied to the plasma processing space 10s. Therefore, the RF power supply 31 may function as at least a portion of a plasma generation section configured to generate plasma from one or more processing gases in the plasma processing chamber 10. Furthermore, by supplying a bias RF signal to the lower electrode, a bias potential can be generated on the substrate W, thereby introducing ionic components from the formed plasma into the substrate W.

[0036] 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 connected 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 13MHz to 150MHz. In one embodiment, the first RF generating unit 31a may also be configured to generate a plurality of source RF signals with different frequencies. One or more source RF signals are supplied to at least one of the lower electrode or the upper electrode, and the second RF generating unit 31b is connected 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 frequency lower than that of the source RF signal. In one embodiment, the bias RF signal has a frequency in the range of 400kHz to 13.56MHz. In one embodiment, the second RF generating unit 31b can also be configured to generate a plurality of bias RF signals with different frequencies. One or more bias RF signals are supplied to the lower electrode. Furthermore, in various embodiments, at least one of the source RF signal and the bias RF signal can be pulsed.

[0037] Furthermore, the power supply 30 may also include a DC power supply 32 integrated into the plasma processing chamber 10. The DC power supply 32 includes a first DC generating unit 32a and a second DC generating unit 32b. In one embodiment, the first DC generating unit 32a is connected to the lower electrode and configured to generate a first DC signal. The generated first DC signal is applied to the lower electrode. In one embodiment, the first DC signal may also be applied to other electrodes, such as the adsorption electrode 115 within the electrostatic chuck 114. In one embodiment, the second DC generating unit 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. Furthermore, the first and second DC generating units 32a and 32b may also be added to the RF power supply 31, and the first DC generating unit 32a may replace the second RF generating unit 31b.

[0038] The exhaust system 40 may be connected to a gas outlet 10e located, for example, at the bottom of the plasma processing chamber 10. The exhaust system 40 may also include a pressure regulating valve and a vacuum pump. The pressure regulating valve adjusts the internal pressure of the plasma processing space 10s. The vacuum pump may also include a turbomolecular pump, a dry pump, or a combination thereof.

[0039] The control unit 2 processes computer-executable commands that cause the plasma processing apparatus 1 to execute the various processes described herein. The control unit 2 may be configured to control the components of the plasma processing apparatus 1 to execute the various processes described herein. In one embodiment, the plasma processing apparatus 1 may also include part or all of the control unit 2. The control unit 2 may also include, for example, a computer 2a. The computer 2a may also include, for example, a processing unit (CPU: Central Processing Unit) 2a1, a memory unit 2a2, and a communication interface 2a3. The processing unit 2a1 may be configured to perform various control actions according to the program stored in the memory unit 2a2. The memory unit 2a2 may also include RAM (Random Access Memory), ROM (Read Only Memory), HDD (Hard Disk Drive), SSD (Solid State Drive), or a combination thereof. The communication interface 2a3 can also communicate with the plasma processing device 1 via communication lines such as LAN (Local Area Network).

[0040] The above descriptions have illustrated various embodiments. However, the embodiments described above are not limited to those described above, and various additions, omissions, substitutions, and changes may be made. Furthermore, the elements of different embodiments may be combined to form other embodiments.

[0041] For example, in this embodiment, the plasma processing system is described using a capacitively coupled plasma processing device 1, but the structure of the plasma processing system is not limited to this. For example, the plasma processing system may also have a processing device that includes a plasma generating unit such as inductively coupled plasma (ICP), electron-cyclotron-resonance plasma (ECR), helicon wave plasma (HWP), or surface wave plasma (SWP). Furthermore, processing devices with various types of plasma generating units, including both AC (alternating current) and DC (direct current) plasma generating units, may also be used.

[0042] Furthermore, in this embodiment, as shown in FIG2, an example is given where the heating electrode 116 has a first heating electrode 116a for heating the substrate W and a second heating electrode 116b for heating the ring assembly 112. However, in the heating electrode 116 disposed inside the electrostatic chuck 114, as shown in FIG3, the second heating electrode 116b for heating the ring assembly 112 can be appropriately omitted. Furthermore, when the second heating electrode 116b is omitted, as shown in FIG4, the second top plate member 122 and the second side wall member 124 of the shielding member 120 can also be omitted, and the first top plate member 121 is electrically connected to the base 113 by the first side wall member 123.

[0043] <Effects of the substrate support disclosed herein> Thus, in this embodiment, the substrate support 11 has a shielding member 120 made of a conductive metal material with a relatively low resistance to radio frequency power disposed inside the electrostatic chuck 114.

[0044] Here, during plasma processing, the radio frequency power applied to the conductive member of the base 113 is transmitted on the surface of the conductive member, i.e., the base 113, and supplied to the plasma processing space. At this time, in a conventional substrate support 11' without the shielding member 120, as shown in FIG5, a portion of the radio frequency power transmitted on the surface of the base 113 may penetrate into the heating electrode 116 electrically floating inside the electrostatic chuck 114. More specifically, the aforementioned situation occurs because, due to the potential difference between the base 113 and the heating electrode 116, a portion of the radio frequency power transmitted on the surface of the base 113 penetrates into the heating electrode 116 as noise, and then discharge occurs due to the expansion of the potential difference. Then, the noise component that penetrates into the heating electrode 116 and the resulting discharge may cause damage to, for example, the heating electrode 116 or the heating power supply 118, or a reduction in power efficiency.

[0045] In this embodiment, the substrate support 11 has a shielding member 120 disposed inside the electrostatic chuck 114, which is at approximately the same potential as the base 113. Therefore, even when radio frequency power is applied to the conductive components of the base 113, as shown in FIG6, the radio frequency power is transmitted on the surface of the shielding member 120 rather than on the surface of the base 113. Thus, the transmission of radio frequency power on the surface of the base 113 to the vicinity of the heating electrode 116 can be suppressed, thereby appropriately suppressing the intrusion of radio frequency power into the heating electrode 116.

[0046] Furthermore, in this embodiment, as described above, the heating electrode 116, which is suspected of being subject to radio frequency power intrusion, is housed within a potential-same space S defined by the base 113 and the shielding member 120, which are configured to be approximately at the same potential. Therefore, since the potential difference between the heating electrode 116 and the base 113 can be suppressed within the potential-same space S, the intrusion of radio frequency power into the heating electrode 116 can be more appropriately suppressed.

[0047] Furthermore, according to this embodiment, since the radio frequency power applied to the conductive member of the base 113 is transmitted on the surface of the shielding member 120 and reaches the vicinity of the surface of the electrostatic chuck 114, i.e., the vicinity of the plasma processing space 10s, the plasma generation efficiency during plasma processing can be improved. Moreover, according to this embodiment, by arranging the first top plate member 121 and the second top plate member 122 at a position closer to the adsorption electrode 115 (the surface of the electrostatic chuck 114) than the heating electrode 116, the plasma generation efficiency can be improved more appropriately.

[0048] Furthermore, in the above embodiment of the substrate support 11, the case in which the heating electrode 116 is housed within a potential space S defined by the base 113 and the shielding member 120, which are configured to be approximately at the same potential, has been described as an example. However, the structure of the substrate support 11 is not limited to this; any structure can be adopted as long as the intrusion of radio frequency power into the heating electrode 116 can be at least attenuated or prevented.

[0049] Specifically, instead of constructing the first top plate member 121 in a circular plate shape as shown in FIG2 so as to completely cover the first heating electrode 116a when viewed from above, as shown in FIG7, the first top plate member 121 can be constructed in an approximately annular shape so as to cover at least a portion of the first heating electrode 116a when viewed from above. In other words, the heating electrode 116 may not necessarily be configured to be housed inside the space S at the same potential. Thus, even when the first top plate member 121 is constructed in an approximately annular shape, the radio frequency power can be transmitted through the surfaces of the second side wall member 124, the second top plate member 122, and the first side wall member 123 to reach the vicinity of the surface of the electrostatic chuck 114, thereby attenuating the intrusion of the radio frequency power into the first heating electrode 116a. Furthermore, since the first top plate member 121 is constructed in an approximately circular shape, the heat generated by the first heating electrode 116a can be directly transferred to the substrate W without passing through the first top plate member 121, thereby improving the heating efficiency of the substrate W of the first heating electrode 116a.

[0050] Furthermore, as long as the shielding member 120 can allow the radio frequency power to reach the vicinity of the surface of the electrostatic chuck 114, as shown in FIG8, the first top plate member 121 can also be omitted. In this case, the intrusion of the radio frequency power into the first heating electrode 116a can be at least attenuated, and the heating efficiency of the substrate W of the first heating electrode 116a can be improved.

[0051] Furthermore, although the illustrations are omitted, as long as this allows high-frequency power to reach the vicinity of the surface of the electrostatic chuck 114, both the first top plate member 121 and the second top plate member 122 of the shielding member 120 can be omitted. In other words, the shielding member 120 can also be constructed using only the side wall members (the first side wall member 123 or the second side wall member 124). Specifically, as shown in FIG2, when the heating electrode 116 has a first heating electrode 116a and a second heating electrode 116b, the shielding member 120 can be constructed using only the second side wall member 124. Also, as shown in FIG3, when the heating electrode 116 has only the first heating electrode 116a, the shielding member 120 can be constructed using only the first side wall member 123. At this time, by positioning the upper end of the shielding member 120 (first sidewall member 123 or second sidewall member 124) at least above the heating electrode 116, preferably near the surface of the electrostatic chuck 114, the intrusion of radio frequency power into the first heating electrode 116a can be at least attenuated.

[0052] Furthermore, as described above, the radio frequency power applied to the conductive member of the base 113 is transmitted across the surfaces of the base 113 and the shielding member 120, reaching the vicinity of the surface of the electrostatic chuck 114, i.e., the first top plate member 121. However, as shown in Figures 7 and 8, when at least a portion of the first top plate member 121 is omitted, a deviation occurs in the supply of radio frequency power to the plasma processing space 10s, resulting in a potential deviation in the uniformity of the plasma processing result on the substrate W.

[0053] Therefore, from the viewpoint of improving the uniformity of the plasma treatment result on the substrate W, it is advisable to configure the shielding member 120 (specifically the first top plate member 121 and the second top plate member 122) to uniformly cover the entire electrostatic chuck 114 when viewed from above.

[0054] Furthermore, generally, the electrostatic chuck 114 of the substrate W is constructed such that its radial size is significantly larger than its thickness. Specifically, for example, the radial size of the electrostatic chuck 114 plus the size of the substrate W is approximately 300 mm or more, while the thickness of the electrostatic chuck 114 is approximately 10 mm or less. Therefore, in this embodiment, when the shielding member 120 is disposed inside the electrostatic chuck 114, impedance design can be performed by changing the placement position and thickness of the shielding member 120, allowing the radio frequency power transmitted on the surface of the base 113 to be transmitted to the surface of the top plate member (first top plate member 121 or second top plate member 122). In other words, by appropriately performing impedance design, even when the side wall members (first side wall member 123 or second side wall member 124) of the shielding member 120 are omitted as shown in FIG. 9, the intrusion of radio frequency power into the first heating electrode 116a can be attenuated. In other words, the shielding member 120 does not necessarily need to be configured to be approximately at the same potential as the base 113. Furthermore, by configuring the first top plate member 121 as the shielding member 120 in this way, when viewed from above, radio frequency power can be transmitted to the entire first top plate member 121 (electrostatic chuck 114), thereby improving the uniformity of the plasma processing results on the substrate W.

[0055] Furthermore, in the above embodiment, in order to appropriately suppress the intrusion of radio frequency power into the heating electrode 116, the first top plate member 121 and the second top plate member 122 of the shielding member 120 are formed of plate-shaped members without holes, respectively. Similarly, the first side wall member 123 and the second side wall member 124 are formed of plate-shaped members without holes, thereby allowing the base 113 to make line contact with the shielding member 120 to completely surround the heating electrode 116. However, the structure of the shielding member 120 is not limited to this, as long as the intrusion of radio frequency power into the heating electrode 116 can be at least attenuated.

[0056] Specifically, for example, the sidewall members of the shielding member 120 can be formed into a grid (mesh) shape, as shown in FIG10. In other words, one or more holes can be formed in the top plate member and the sidewall members of the shielding member 120. In this case, the radio frequency power transmitted on the surface of the base 113 can be transmitted along the surface of the shielding member 120, that is, the amount of radio frequency power transmitted to the vicinity of the heating electrode 116 can be attenuated, thereby suppressing the intrusion of radio frequency power into the heating electrode 116. Furthermore, when the first top plate member 121 is formed into a grid shape, the radio frequency power can be transmitted to the entire first top plate member 121 (electrostatic chuck 114) when viewed from above, thereby improving the uniformity of the plasma processing result on the substrate W.

[0057] Similarly, as shown in FIG11, by forming the sidewall members of the shielding member 120 into a longitudinal grid, the amount of radio frequency power transmitted to the vicinity of the heating electrode 116 can be attenuated at least, thereby suppressing the intrusion of radio frequency power into the heating electrode 116.

[0058] Furthermore, Figures 10 and 11 illustrate the case where the sidewall members of the shielding member 120 are constructed in a grid or longitudinal grid pattern. Of course, the top plate member of the shielding member 120 can also be constructed in a grid or longitudinal grid pattern. When the top plate member is constructed in a grid or longitudinal grid pattern, when viewed from above, the radio frequency power can be transmitted to the entire electrostatic chuck 114, thereby improving the uniformity of the plasma processing results on the substrate W.

[0059] Furthermore, as shown in Figures 10 and 11, instead of making the shielding member 120 in full-circumferential contact with the base 113, when multiple point contacts are made, if the positions of these contact points are not uniformly arranged around the heating electrode 116, there is a risk of deviation in the plasma processing results or that the shielding member 120 and the base 113 cannot be properly constructed to be approximately at the same potential. Therefore, when the shielding member 120 is made in point contact with the base 113, it is ideal to arrange the positions of these contact points evenly around the entire circumference of the electrostatic chuck 114. Specifically, for example, when the contact points are designed to be six points, it is ideal to arrange the contact points every 60 degrees in the circumferential direction. Also, when the shielding member 120 is made in point contact with the base 113, it is ideal to increase the number of these contact points as much as possible in order to properly construct the shielding member 120 and the base 113 to be at the same potential.

[0060] Furthermore, in the above embodiment, when the heating electrode 116 has a first heating electrode 116a and a second heating electrode 116b, the example described is that the first heating electrode 116a and the second heating electrode 116b are integrally housed in the same potential space S using a shielding member 120. The first heating electrode 116a and the second heating electrode 116b can also be independently housed in the same potential space S. In other words, a plurality of shielding members 120 can be arranged inside the electrostatic chuck 114 to form a plurality of same potential spaces S, and the first heating electrode 116a and the second heating electrode 116b can be respectively arranged in these plurality of same potential spaces S.

[0061] Furthermore, in the above embodiment, taking the case where the heating electrode 116, which serves as a circuit, is disposed inside the electrostatic chuck 114 as an example, the heating electrode 116 only needs to be disposed such that at least a portion of it contacts the dielectric portion.

[0062] Specifically, in one embodiment, the heating electrode 116 can be disposed inside the electrostatic chuck 114 or the bonding member G, which serves as the dielectric part, or it can be disposed across the electrostatic chuck 114 and the bonding member G. Furthermore, in another embodiment, the heating electrode 116 can be attached to the base 113 with one side as shown in FIG12, or it can be partially embedded in the base 113 as shown in FIG13.

[0063] Furthermore, in this embodiment of the substrate support 11, as described above, an RF cutoff filter 117 is provided on the power supply cable connecting the heating electrode 116 and the heating power supply 118 to attenuate or block radio frequency power. Therefore, even if, for example, the shielding member 120 cannot completely prevent radio frequency power from entering the heating electrode 116, noise components reaching the heating power supply 118 can be appropriately suppressed. Especially in this embodiment, since the amount of radio frequency power entering the heating electrode 116 is attenuated by the shielding member 120, protection of the heating power supply 118 by the RF cutoff filter 117 is more easily achieved.

[0064] In other words, in this embodiment, the attenuation or prevention of radio frequency power intrusion into the heating electrode 116 can be achieved solely through the action of the shielding member 120. Therefore, in the substrate support 11 of this embodiment, the RF cutoff filter 117 disposed on the power supply cable can be appropriately miniaturized or omitted.

[0065] The RF cutoff filter 117 typically needs to correspond to a plurality of temperature regulation regions defined by a plurality of heating electrodes 116 individually or in combination, and a plurality of such filters are provided in the space below the substrate support 11 (electrostatic chuck 114). That is, a plurality of RF cutoff filters 117 and the power cables for connecting them need to be arranged in the space below the substrate support 11, thus occupying space below the substrate support 11.

[0066] In this respect, according to this embodiment, by providing a shielding member 120 inside the electrostatic chuck 114, the RF cutoff filter 117 can be miniaturized or omitted as described above. Therefore, the power supply cable and RF cutoff filter 117 disposed in the lower space of the substrate support 11 (electrostatic chuck 114) can be reduced, thereby improving the space efficiency of the lower space and reducing the cost of installing the substrate support 11.

[0067] Furthermore, in the conventional substrate support 11, the radio frequency power that enters the heating electrode 116 with noise components is lost when passing through the RF cutoff filter 117. That is, the RF cutoff filter 117 acts as a resistor, thus resulting in reduced power efficiency. Moreover, in particular, when the resistance value of the RF cutoff filter 117 deviates, this deviation in resistance value manifests as a mechanical malfunction of the plasma processing apparatus 1. In this respect, according to this embodiment, since the RF cutoff filter 117 can be omitted, the power loss caused by the RF cutoff filter 117 can be suppressed, thereby improving power efficiency, and the mechanical malfunction problem caused by the RF cutoff filter 117 can be improved.

[0068] Furthermore, in the above embodiment, the example described is that the shielding member 120 for suppressing or preventing the intrusion of radio frequency power into the circuit is disposed inside the electrostatic chuck 114, or more broadly, inside the substrate support 11 constituting the lower electrode mechanism. However, the location of the shielding member disclosed herein is not limited to this, and it can be disposed in any component having a circuit for suppressing the intrusion of radio frequency power inside.

[0069] Specifically, for example, when the upper electrode mechanism of the plasma processing device 1 has a circuit inside, rather than inside the lower electrode mechanism, a shielding member may be arranged inside the upper electrode mechanism.

[0070] FIG14 is a cross-sectional view showing a schematic structure of the upper electrode mechanism 130 in one embodiment. As shown in FIG14, in one embodiment, the upper electrode mechanism 130 includes a metal plate 131 as an electrode portion and a spray head 132. The metal plate 131 and the spray head 132 are laminated by a bonding member G. Furthermore, in this embodiment, the spray head 132 constituting the upper electrode mechanism 130 and the bonding member G are equivalent to the "dielectric portion" of the disclosed technology.

[0071] The metal plate 131 is constructed of a conductive component, such as an Al alloy. The conductive component 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. Furthermore, the metal plate 131 has at least one flow path C inside for controlling the temperature of a spray head 132 whose temperature varies due to the heat input of the plasma. A heat transfer medium (temperature regulating fluid) from a cooling unit (not shown) is circulated and supplied to the flow path C.

[0072] A plurality of gas inlets 13c are formed in the spray head 132 along its thickness direction (vertical direction). The gas inlets 13c are connected to the gas supply section 20 via a gas diffusion chamber 13b and a gas supply port 13a formed inside the metal plate 131, and are configured to introduce at least one processing gas from the gas supply section 20 into the plasma processing space 10s. Furthermore, the spray head 132 has at least one heating electrode 140 inside for controlling the temperature of the spray head 132 as its temperature varies due to the heat input of the plasma. In addition, in this embodiment, the heating electrode 140 corresponds to the "circuit" of the disclosed technology.

[0073] Furthermore, in one embodiment, a shielding member 150 is disposed inside the upper electrode mechanism 130, more specifically inside the spray head 132, for attenuating or preventing the intrusion of radio frequency power applied to the conductive member (upper electrode) of the metal plate 131 to the heating electrode 140. The shielding member 150 is made of a conductive metal material (e.g., tungsten or titanium) that has a relatively low resistance to the radio frequency power applied to the upper electrode. Furthermore, in one embodiment, the shielding member 150 is disposed inside the spray head 132 at the same potential as the metal plate 131, at least surrounding the heating electrode 140. In other words, in one embodiment, the upper electrode mechanism 130 houses the heating electrode 140, which is suspected of being subject to radio frequency power intrusion, within the same potential space S defined by the metal plate 131 and the shielding member 150, which are disposed at approximately the same potential.

[0074] Furthermore, in one embodiment of the upper electrode mechanism 130, by distributing the shielding member 150 inside the spray head 132, the radio frequency power applied to the upper electrode is transmitted across the surfaces of the metal plate 131 and the shielding member 150, reaching the vicinity of the surface of the spray head 132, i.e., the vicinity of the plasma processing space 10s. As a result, the intrusion of the radio frequency power into the heating electrode 140 can be appropriately suppressed.

[0075] Furthermore, the structure of the shielding member 150 disposed inside the spray head 132 is not limited to the example shown in the figure. That is, similar to the shielding member 120 disposed inside the electrostatic chuck 114, either the top plate member or the side wall member constituting the shielding member 150 may be omitted. These top plate members and side wall members may also be constructed in a grid pattern or a longitudinal grid pattern.

[0076] Furthermore, the arrangement of the heating electrode 140 as a circuit is not limited to the example shown in the figure, as long as at least a portion is arranged to contact the dielectric part. Specifically, in one embodiment, the heating electrode 140 can be arranged inside the spray head 132 or the bonding member G, which serves as the dielectric part, or it can be arranged across the spray head 132 and the bonding member G. In another embodiment, the heating electrode 140 can contact the spray head 132 or the bonding member G, which serves as the dielectric part, and it can also be joined to the metal plate 131 on one side, or it can be partially embedded in the metal plate 131.

[0077] Thus, the shielding component of the disclosed technology is not limited to the interior of the electrostatic chuck 114 of the lower electrode mechanism. It can be disposed inside any component as long as it has a circuit inside to prevent the intrusion of radio frequency power.

[0078] Furthermore, in the above embodiment, the example given is the case where the circuit of the object to be protected against the intrusion of radio frequency power is the heating electrode. However, the type of circuit is not limited to this. For example, the shielding member may be configured to protect any circuit that may suffer damage due to the intrusion of radio frequency power, such as thermocouples, piezoelectric elements, or the drive mechanism of other components.

[0079] The embodiments disclosed herein should be considered as examples of all points, not as limitations. The above embodiments may also be omitted, replaced, or modified in various forms without departing from the scope and spirit of the appended patent application. [Simplified Explanation of the Diagram]

[0008] Figure 1 is a longitudinal cross-sectional view showing a structural example of the plasma processing system of this embodiment. Figure 2 is a longitudinal cross-sectional view showing a structural example of the substrate support of this embodiment. Figure 3 is a longitudinal cross-sectional view showing a structural example of the substrate support of another embodiment. Figure 4 is a longitudinal cross-sectional view showing a structural example of the substrate support of another embodiment. Figure 5 is an explanatory diagram showing the flow of radio frequency power in a conventional substrate support. Figure 6 is an explanatory diagram showing the flow of radio frequency power in the substrate support of this embodiment. Figure 7 is a longitudinal cross-sectional view showing a structural example of the substrate support of another embodiment. Figure 8 is a longitudinal cross-sectional view showing a structural example of the substrate support of another embodiment. Figure 9 is a longitudinal cross-sectional view showing a structural example of the substrate support of another embodiment. Figure 10 is a longitudinal cross-sectional view showing a structural example of the substrate support of another embodiment. Figure 11 is a longitudinal cross-sectional view showing a structural example of the substrate support of another embodiment. Figure 12 is a longitudinal cross-sectional view showing a structural example of the substrate support of another embodiment. Figure 13 is a longitudinal cross-sectional view showing a structural example of the substrate support of another embodiment. Figure 14 is a longitudinal cross-sectional view showing a structural example of the upper electrode mechanism in one embodiment.

Claims

1. A plasma processing apparatus comprising: a processing chamber; and an electrode mechanism for plasma processing; the electrode mechanism comprising: an electrode portion to which radio frequency power is applied; a dielectric portion stacked with the electrode portion; a circuit, at least a portion of which is disposed within the dielectric portion; and a shielding member disposed within the dielectric portion, configured to overlap at least a portion of the circuit in at least one of a top view or a side view; the electrode mechanism being a lower electrode mechanism for plasma processing, comprising a substrate support body supporting a substrate on a substrate support surface, the circuit being used to heat a first heating electrode of the substrate supported on the substrate support surface; and the shielding member being configured to be integrally formed with the electrode portion to house the first heating electrode.

2. The plasma treatment apparatus as claimed in claim 1, wherein, The shielding member is configured to be at the same potential as the electrode portion.

3. The plasma treatment apparatus as described in claim 2, wherein, The shielding member will at least attenuate the radio frequency power applied to the electrode.

4. The plasma treatment apparatus as described in any of claims 1 to 3, wherein, The shielding component is made of either tungsten or titanium.

5. The plasma treatment apparatus as claimed in claim 1, wherein, The shielding member includes: a top plate member disposed along the surface direction of the dielectric portion; and a side wall member disposed along the thickness direction of the dielectric portion, wherein the top plate member is electrically connected to the electrode portion.

6. The plasma treatment apparatus as claimed in claim 5, wherein, The top plate member is disposed between the first heating electrode and the substrate support surface inside the dielectric portion, and the distance between the first heating electrode and the top plate member is at least greater than the distance between the substrate support surface and the top plate member.

7. The plasma treatment apparatus as claimed in claim 5, wherein, The sidewall member is in line contact with the electrode portion and is configured to completely surround the first heating electrode.

8. The plasma treatment apparatus as claimed in claim 5, wherein, The sidewall member is configured to make point contact with the electrode portion at multiple points around the electrode portion, thereby surrounding the entire circumference of the first heating electrode.

9. The plasma treatment apparatus as claimed in claim 8, wherein, The electrode portion and the sidewall member have a plurality of contact points that are equally spaced around the circumference of the electrode portion.

10. The plasma processing apparatus as claimed in claim 1, wherein, The substrate support includes a ring support surface supporting an edge ring, and the circuit includes a second heating electrode for heating the edge ring supported on the ring support surface; the shielding member is configured to house the first heating electrode and the second heating electrode as a single unit.

11. The plasma treatment apparatus as claimed in claim 1, wherein, The substrate support includes a ring support surface that supports an edge ring, and the circuit includes a second heating electrode that heats the edge ring supported on the ring support surface; the shielding member is configured to independently house the first heating electrode and the second heating electrode.

12. A plasma processing apparatus comprising: a processing chamber; and an electrode mechanism for plasma processing; the electrode mechanism comprising: an electrode portion to which radio frequency power is applied; a dielectric portion disposed in a laminated configuration with the electrode portion; a circuit, at least a portion of which is disposed within the dielectric portion; and a shielding member disposed within the dielectric portion, configured to overlap at least a portion of the circuit in at least one of a top view or a side view; the electrode mechanism being an upper electrode mechanism for plasma processing, comprising: a spray head for supplying processing gas to a processing space housing a substrate during plasma processing; the circuit for heating a heating electrode of the spray head; and the shielding member being configured to be integrally formed with the electrode portion and housing the heating electrode.

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