Plasma processing apparatus, upper electrode assembly used in plasma processing apparatus, method for manufacturing upper electrode assembly, and method for reproducing upper electrode assembly

Abstract

This invention provides a technique for effectively regulating the temperature of the electrode plate constituting an upper electrode assembly. A plasma processing apparatus includes: a plasma processing chamber; a substrate support disposed within the plasma processing chamber; a lower electrode disposed within the substrate support; a conductive member disposed above the substrate support, having at least one refrigerant inlet and at least one refrigerant outlet, connected to a radio frequency potential or a DC potential; and an upper electrode assembly. The upper electrode assembly includes: a conductive plate detachably connected to the bottom surface of the conductive member, having one or more refrigerant channels communicating with the at least one refrigerant inlet and the at least one refrigerant outlet; an electrode plate disposed below the conductive plate; and a conductive bonding piece disposed between the electrode plate and the conductive plate.

Description

Technical Field

[0001] This invention relates to a plasma treatment apparatus, an upper electrode assembly used in the plasma treatment apparatus, a method for manufacturing the upper electrode assembly, and a method for regenerating the upper electrode assembly. Prior Technology

[0002] Patent Document 1 discloses the configuration of a composite spray head electrode assembly in a plasma treatment apparatus. In Patent Document 1, among the plurality of components constituting the composite spray head electrode assembly, an interfacial adhesive, such as silicone, is disposed between the electrode plate and the support plate to ensure conductivity and simultaneously control the temperature of the electrode plate.

[0003] Furthermore, Patent Document 2 discloses an upper electrode structure for a plasma processing apparatus. In the upper electrode structure of Patent Document 2, the temperature control of the first plate facing the plasma processing space is achieved by forming a refrigerant flow channel on a second plate located above the first plate. [Previous Technical Documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2012-500471 [Patent Document 2] Japanese Patent Application Publication No. 2015-216261 Summary of the Invention

[0005] [The problem the invention aims to solve]

[0006] According to the technology of the present invention, when the heat input entering the processing chamber increases, the thermal resistance generated by the component joint is reduced, and the temperature of the electrode plate constituting the upper electrode assembly is effectively regulated. [Methods for solving problems]

[0007] One embodiment of the present invention is a plasma processing apparatus comprising: a plasma processing chamber; a substrate support disposed within the plasma processing chamber; a lower electrode disposed within the substrate support; a conductive member disposed above the substrate support, having at least one refrigerant inlet and at least one refrigerant outlet, and connected to a radio frequency potential or a DC potential; and an upper electrode assembly; the upper electrode assembly comprising: a conductive plate detachably connected to the bottom surface of the conductive member, having one or more refrigerant channels communicating with the at least one refrigerant inlet and the at least one refrigerant outlet; an electrode plate disposed below the conductive plate; and a conductive bonding piece disposed between the electrode plate and the conductive plate. [Effects of the Invention]

[0008] According to the present invention, when the heat input entering the processing chamber increases, the thermal resistance caused by the component joint can be reduced, and the temperature of the electrode plate constituting the upper electrode assembly can be effectively adjusted. Simple Explanation of the Diagram

[0009] [Figure 1] is a schematic diagram illustrating the configuration of a plasma treatment system. [Figure 2] is an explanatory diagram showing a magnified portion of the upper electrode assembly. [Figure 3] is a schematic diagram illustrating the formation of a conductive coating on a conductive plate. [Figure 4] is a flowchart showing the manufacturing method of the upper electrode assembly. [Figure 5] is a flowchart showing the regeneration method of the upper electrode assembly. [Figure 6] is an explanatory diagram showing an example of the specific shape of a refrigerant channel. [Figure 7] is an explanatory diagram showing an example of the specific shape of a refrigerant channel. [Figure 8] is an explanatory diagram showing an example of the specific shape of a refrigerant channel. [Figure 9] is an explanatory diagram showing an example of the specific shape of a refrigerant channel. [Figure 10] is an explanatory diagram showing an example of the specific shape of a refrigerant channel. [Figure 11] is an explanatory diagram showing an example of the specific shape of a refrigerant channel. [Figure 12](a) and (b) are explanatory diagrams showing an example of the specific shape of a refrigerant channel. Implementation

[0010] In the manufacturing process of semiconductor devices, plasma is generated by exciting the processing gas supplied to the chamber, and various plasma processes such as etching, film formation, and diffusion are performed on the semiconductor substrate (hereinafter referred to as "substrate") supported by the substrate support. These plasma processes are performed using, for example, a capacitively coupled plasma (CCP) plasma processing apparatus, which has an upper electrode assembly that forms part of the top of the chamber.

[0011] In recent years, with the increasing demand for miniaturization of patterns formed on substrate surfaces during semiconductor device manufacturing, plasma processing equipment needs to set the radio frequency (RF) power supply to a high output mode and perform etching processes such as deep drilling. However, to shorten etching time or improve ion penetration when performing deep drilling etching, the RF output needs to be increased, which results in a problem with the heat input into the chamber.

[0012] When the heat input into the chamber is too large, concerns arise that the adhesion of etching byproducts may change due to the increased temperature, or the chamber's structural components may be damaged by the heat. Therefore, from the perspective of uniformly controlling the results of plasma processing on the substrate, or preventing damage to the chamber's structural components, it is necessary to improve the cooling performance of the chamber in accordance with the plasma heat input.

[0013] In Patent Document 1, the electrode plate located on the plasma-exposed surface is mounted using interfacial adhesive in the composite spray head electrode assembly (upper electrode assembly) that constitutes the chamber, thereby improving the tightness of the fit and thermal conductivity. Furthermore, in Patent Document 2, electrostatic adsorption is used to adsorb the first and second plates in the upper electrode structure, thereby improving the tightness of the fit and thermal conductivity.

[0014] However, the interfacial molten adhesive described in Patent Document 1, being formed from, for example, silicone, has low thermal conductivity and high thermal resistance. Therefore, when the plasma heat input is too large, it is necessary to further improve the thermal conductivity. Furthermore, in the case of using silicone to form the interfacial molten adhesive, silicone has a high volume resistivity, necessitating the provision of additional electrical contacts with the electrode plate, which is a challenge. Although adding fillers to silicone can improve thermal conductivity, this is not feasible due to the reduced tightness of the adhesion, which increases the interfacial thermal resistance. Moreover, even when using the electrostatic adsorption method described in Patent Document 2, the effect of reducing thermal resistance is still unsatisfactory when the heat input entering the chamber is too large, leaving room for further improvement.

[0015] The present invention was made in view of the above-mentioned circumstances. The present invention provides a technique that, even in cases where the heat input into the chamber is excessive, can still effectively regulate the temperature of the electrode plates constituting the upper electrode assembly compared to conventional techniques. Hereinafter, with reference to the drawings, a plasma processing system according to one embodiment and a plasma processing method including the etching method according to this embodiment will be described. Furthermore, in this specification and drawings, elements having substantially the same functional configuration are labeled with the same symbols, thus omitting repeated descriptions.

[0016] <Plasma Treatment System> First, the plasma treatment system according to this embodiment will be described. Figure 1 is a longitudinal sectional view showing the general structure of the plasma treatment system according to this embodiment.

[0017] The plasma processing system includes a capacitively coupled plasma processing device 1 and a control unit 2. The plasma processing device 1 includes a plasma processing chamber 10, a gas supply unit 20, a power supply 30, and an exhaust system 40. Furthermore, the plasma processing device 1 includes a substrate support unit 11 and a gas introduction unit. The substrate support unit 11 is disposed within the plasma processing chamber 10. The gas introduction unit introduces at least one processing gas into the plasma processing chamber 10. The gas introduction unit includes an upper electrode assembly 13. The upper electrode assembly 13 is disposed above the substrate support unit 11. In one embodiment, the upper electrode assembly 13 is mounted on a conductive member 10b (canopy) constituting the top of the plasma processing chamber 10. Inside the plasma processing chamber 10, a plasma processing space 10s is formed by the upper electrode assembly 13, the sidewall 10a of the plasma processing chamber 10, and the substrate support unit 11. The plasma processing chamber 10 has: at least one gas supply port for supplying at least one processing gas to the plasma processing space 10s; and at least one gas outlet for discharging gas from the plasma processing space 10s. The sidewall 10a is grounded. The upper electrode assembly 13 and the substrate support portion 11 are electrically insulated from the plasma processing chamber 10.

[0018] The substrate support portion 11 includes a body portion 111 and a ring assembly 112. The top surface of the body portion 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] In one embodiment, the main body 111 includes a base 113 and an electrostatic chuck 114. The base 113 includes a conductive member. The conductive member of the base 113 functions as a lower electrode. The electrostatic chuck 114 is disposed on the top surface of the base 113. The top surface of the electrostatic chuck 114 has the aforementioned central region 111a and an annular region 111b.

[0020] Furthermore, omitting the illustrations here, the substrate support 11 may also include a temperature control module, which adjusts at least one of the ring assembly 112, the electrostatic chuck 114, and the substrate W to a target temperature. The temperature control module may include a heater, a heat transfer medium, a flow channel, or a combination thereof. A heat transfer fluid, such as brine or gas, flows through the flow channel. Alternatively, the substrate support 11 may include a heat transfer gas supply unit, which supplies heat transfer gas (backside gas) between the back side of the substrate W and the top surface of the electrostatic chuck 114.

[0021] The gas supply unit 20 may include at least one gas source 21 and at least one flow controller 22. In one embodiment, the gas supply unit 20 supplies at least one process gas from its respective gas source 21 to the upper electrode assembly 13 via corresponding flow controllers 22. Each flow controller 22 may include, for example, a mass flow controller or a pressure-controlled flow controller. Furthermore, the gas supply unit 20 may include one or more flow modulation elements that modulate or pulse the flow rate of at least one process gas.

[0022] The power supply 30 includes an RF power supply 31 coupled to the plasma processing chamber 10 via at least one impedance matching circuit. The RF power supply 31 supplies at least one RF signal (RF power), such as a source RF signal and a bias RF signal, to the conductive members (lower electrode) of the substrate support portion 11 and / or the conductive members (upper electrode) of the upper electrode assembly 13. This allows plasma to be formed from at least one processing gas supplied to the plasma processing space 10s. Therefore, the RF power supply 31 can function as at least part of a plasma generation unit that generates 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 is generated on the substrate W, which can introduce ionic components from the formed plasma into the substrate W.

[0023] In one embodiment, the RF power supply 31 includes a first RF signal generating unit 31a and a second RF signal generating unit 31b. The first RF signal generating unit 31a is coupled to the lower electrode and / or the upper electrode via at least one impedance matching circuit, and generates 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 160MHz. In another embodiment, the first RF signal generating unit 31a may generate multiple source RF signals with different frequencies. The generated one or multiple source RF signals are supplied to the lower electrode and / or the upper electrode. The second RF signal generating unit 31b is coupled to the lower electrode via at least one impedance matching circuit, and generates a bias RF signal (bias RF power). In one embodiment, the bias RF signal has a frequency lower than the source RF signal. In another embodiment, the bias RF signal has a frequency in the range of 400kHz to 13.56MHz. In one embodiment, the second radio frequency signal generating unit 31b may generate a complex number of bias radio frequency signals with different frequencies. The generated one or more bias radio frequency signals are supplied to the lower electrode. Furthermore, in various embodiments, at least one of the source radio frequency signal and the bias radio frequency signal may be pulsed.

[0024] Furthermore, the power supply 30 may include a DC power supply 32 coupled to the plasma processing chamber 10. The DC power supply 32 includes a first DC signal generating unit 32a and a second DC signal generating unit 32b. In one embodiment, the first DC signal generating unit 32a is connected to the lower electrode and generates a first DC signal. The generated first DC signal is applied to the lower electrode. In another embodiment, the first DC signal may be applied to other electrodes within the electrostatic chuck 114, such as adsorption electrodes. In another embodiment, the second DC signal generating unit 32b is connected to the upper electrode and generates 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 signal generating units 32a and 32b may be further provided outside the radio frequency power supply 31, or the first DC signal generating unit 32a may be provided instead of the second radio frequency signal generating unit 31b.

[0025] The exhaust system 40 can be connected to, for example, a gas outlet 10e located at the bottom of the plasma processing chamber 10. The exhaust system 40 may include a pressure regulating valve and a vacuum pump. The internal pressure of the plasma processing space 10s can be adjusted by means of the pressure regulating valve. The vacuum pump may include a turbomolecular pump, a dry pump, or a combination thereof.

[0026] The control unit 2 processes computer-executable commands that cause the plasma processing apparatus 1 to perform the various steps described herein. The control unit 2 can control various elements of the plasma processing apparatus 1 to perform the various steps described herein. In one embodiment, 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 can perform various control actions according to the program stored in the storage unit 2a2. The storage unit 2a2 may include: Random Access Memory (RAM), Read Only Memory (ROM), Hard Disk Drive (HDD), Solid State Drive (SSD), or combinations thereof. The communication interface 2a3 can also communicate with the plasma processing device 1 via communication lines such as a local area network (LAN).

[0027] <Upper Electrode Assembly> Next, using FIG2, the constituent elements of the aforementioned upper electrode assembly 13 and the plasma processing apparatus 1 attached to the upper electrode assembly 13 will be described. FIG2 is an explanatory diagram showing an enlarged portion of the upper electrode assembly 13.

[0028] As shown in Figure 2, in one embodiment, the upper electrode assembly 13 is mounted on the bottom surface of the conductive member 10b disposed above the substrate support portion 11, and includes an electrode plate 120 and a conductive plate 130. The conductive member 10b may form the top of the plasma processing chamber 10, or it may be mounted on the top of the plasma processing chamber 10. The electrode plate 120 and the conductive plate 130 are stacked vertically with a conductive bonding sheet 140 between them. In other words, the upper electrode assembly 13 consists of the electrode plate 120, the conductive bonding sheet 140, and the conductive plate 130 stacked from below. That is, the electrode plate 120 is disposed below the conductive plate 130.

[0029] The conductive member 10b is formed of a conductive material (second conductive material) such as Al (aluminum). The electrode plate 120 is formed of, for example, Si or SiC, with its bottom surface exposed to the plasma processing space 10s. That is, the electrode plate 120 has a plasma exposure surface, exposed to the plasma generated in the plasma processing space 10s. The electrode plate 120 functions as an upper electrode in the plasma processing. A plurality of gas inlets 13a are formed in the electrode plate 120 through a passage in the thickness direction (vertical direction). The gas inlets 13a are connected to the gas supply section 20 via a gas diffusion space 13b formed inside the conductive member 10b and a gas supply port 13c, and introduce at least one processing gas from the gas supply section 20 into the plasma processing space 10s.

[0030] The conductive member 10b functions as a conductive support, supporting the upper electrode assembly 13, which includes the electrode plate 120, conductive bonding piece 140, and conductive plate 130, on its detachable surface 137 in a detachable manner. The upper electrode assembly 13 is fixed to the conductive member 10b by a fixing unit. The fixing unit can employ various methods, such as the suspension type described in Japanese Patent Application Publication No. 2016-18768 or 2016-18769, the screw fixing type described in US2009 / 0095424A1, and the adhesive type described in US2021 / 0032752A1.

[0031] Inside the conductive member 10b, at least one gas diffusion space 13b and at least one gas supply port 13c are formed. The gas diffusion space 13b and the gas supply port 13c are connected to the gas supply section 20, and as described above, at least one processing gas from the gas supply section 20 is introduced into the plasma processing space 10s through the gas inlet 13a formed on the electrode plate 120.

[0032] The conductive plate 130 has at least one refrigerant channel 131 inside, which adjusts the temperature of the electrode plate 120, which fluctuates due to plasma heat input, to a target temperature. A heat transfer fluid, such as brine or gas, flows through the refrigerant channel 131, passing through the conductive member 10b and circulating with an external quencher (not shown) via a refrigerant inlet 133 and a refrigerant outlet 134 at the top of the conductive member 10b. In one embodiment, the conductive member 10b has a top surface and a bottom surface. The conductive member 10b has at least one refrigerant inlet 133 and at least one refrigerant outlet 134 on its top surface. The conductive member 10b has at least one first refrigerant channel extending from the at least one refrigerant inlet 133 to the bottom surface of the conductive member 10b. The conductive member 10b has at least one second refrigerant channel extending from the bottom surface of the conductive member 10b to the at least one refrigerant outlet 134. Furthermore, the conductive plate 130 has one or more refrigerant channels 131, which communicate with at least one refrigerant inlet 133 via at least one first refrigerant channel, and with at least one refrigerant outlet 134 via at least one second refrigerant channel. The specific shape of the refrigerant channel 131 will be described below with reference to Figures 6-12. Also, the conductive member 10b is connected to an radio frequency potential or a DC potential. In one embodiment, the conductive member 10b is connected to an radio frequency power supply 31 or a DC power supply 32.

[0033] In one embodiment, the conductive plate 130 is formed of a conductive material (a third conductive material) that can impart greater clamping force and has higher toughness. This is because when the conductive plate 130 is adhered and fixed to the conductive member 10b, torque and other stresses may sometimes occur. In another embodiment, the conductive plate 130 is formed of a metal matrix composite material called Mo (molybdenum) or MMC (Metal Matrix Composites).

[0034] In one embodiment, the conductive plate 130 is formed of a high-resistivity material such as Al-Si, AlN, or SiC. In this case, a conductive coating 139 is formed on the conductive plate 130. Figure 3 is a schematic diagram illustrating the formation of the conductive coating 139 on the conductive plate 130. As shown in Figure 3, the conductive coating 139 can be formed in such a way that the conductive member 10b and the conductive bonding piece 140 are electrically connected, for example, it can be formed in such a way that it covers the entire bottom surface and side surface of the conductive plate 130 and a portion of the top surface. The conductive coating 139 is formed of a conductive material such as aluminum.

[0035] In one embodiment, the conductive bonding piece 140 is formed of a so-called solder metal having a melting point of 400°C to 1000°C. In another embodiment, the conductive bonding piece 140 is formed of an Al-Si alloy, an Al-Mg alloy, or an Al-Si-Mg alloy. The bonding of the conductive plate 130 and the electrode plate 120 using the conductive bonding piece 140 is performed by a pressurization process using gas pressure, such as hot pressing or HIP (Hot Isostatic Pressing). Therefore, the electrode plate 120 is bonded to the conductive plate 130 by the conductive bonding piece 140 without any other fixing elements.

[0036] The electrode plate 120 is, for example, a Si or SiC electrode. That is, the electrode plate 120 is formed of Si or SiC. For example, in plasma etching processes, the electrode plate 120, being the plasma-exposed surface, will gradually peel off or deteriorate with use, and etching byproducts will adhere, making it necessary to regenerate or replace it appropriately. Of course, it is also necessary to prepare a new electrode plate 120 at the start of the plasma process. The manufacturing and regeneration methods of the upper electrode assembly 13 including this electrode plate 120 will be described below with reference to Figures 4 and 5.

[0037] In one embodiment, the difference in the coefficient of linear expansion between the conductive plate 130 and the electrode plate 120 is less than 2 ppm / ℃. This is because, when the conductive bonding sheet 140 is used as a bonding layer to join the conductive plate 130 and the electrode plate 120, it is necessary to suppress the generation of particles due to poor bonding or scratching between the conductive plate 130 and the electrode plate 120. If the difference in the coefficient of linear expansion between the two exceeds 2 ppm / ℃, there is a risk that the thermal stress generated by the difference in linear expansion will act on the bonding interface from the bonding temperature of the conductive bonding sheet 140 (melting temperature, 550℃ for Al-Si solder metal) until room temperature, causing damage. Furthermore, the conductive bonding sheet 140 has a smaller thickness than the electrode plate 120.

[0038] <Substrate Processing Method Using Plasma Processing Equipment> Next, an example of a method for processing substrate W using the plasma processing apparatus 1 configured as described above will be explained. Furthermore, in the plasma processing apparatus 1, various plasma treatments are performed on the substrate W, such as etching, film formation, and diffusion.

[0039] First, the substrate W is fed into the plasma processing chamber 10 and placed on the electrostatic chuck 114 of the substrate support portion 11. Next, a voltage is applied to the adsorption electrodes of the electrostatic chuck 114, thereby using electrostatic force to adsorb and hold the substrate W to the electrostatic chuck 114.

[0040] When the substrate W is adsorbed and held in place by the electrostatic chuck 114, the internal pressure of the plasma processing chamber 10 is reduced to a predetermined vacuum level. Next, processing gas is supplied from the gas supply unit 20 to the plasma processing space 10s via the upper electrode assembly 13. Furthermore, source radio frequency power for plasma generation is supplied from the first radio frequency signal generation unit 31a to the lower electrode to excite the processing gas and generate plasma. At this time, bias radio frequency power can also be supplied from the second radio frequency signal generation unit 31b. Then, in the plasma processing space 10s, plasma processing is applied to the substrate W by the action of the generated plasma.

[0041] During the plasma processing of substrate W, the electrode plate 120, which is disposed adjacent to the plasma processing space 10s, experiences temperature fluctuations due to the input of plasma heat. Furthermore, when the electrode plate 120 experiences temperature fluctuations, there is a risk that the plasma processing of substrate W may become in-plane non-uniform.

[0042] Therefore, in this embodiment, the temperature of the electrode plate 120 is controlled by the refrigerant channel 131 contained within the conductive plate 130. Specifically, for example, when the temperature of the electrode plate 120 rises due to plasma heat input, the temperature of the conductive plate 130 is lowered by circulating a heat transfer fluid inside the refrigerant channel 131. In this way, heat is transferred from the electrode plate 120 to the conductive plate 130, thereby reducing the temperature of the electrode plate 120.

[0043] In this embodiment, the upper electrode assembly 13 consists of an electrode plate 120, a conductive bonding sheet 140, and a conductive plate 130 stacked sequentially, and the electrode plate 120 and the conductive plate 130 are joined by a metal bonding method called hard soldering. Therefore, in this embodiment, heat transfer along the stacking direction of the electrode plate 120 and the conductive plate 130, i.e., the vertical direction, is promoted, and the temperature of the electrode plate 120 can be effectively controlled.

[0044] At the end of the plasma processing, the supply of source radio frequency power from the first radio frequency signal generation unit 31a is stopped, and the supply of processing gas from the gas supply unit 20 is also stopped. If bias radio frequency power was supplied during the plasma processing, the supply of that bias radio frequency power is also stopped.

[0045] Next, the electrostatic chuck 114 is stopped from adsorbing and holding the substrate W, and the electrical properties of the substrate W and the electrostatic chuck 114 are neutralized after plasma treatment. Then, the substrate W is detached from the electrostatic chuck 114 and sent out of the plasma treatment apparatus 1. In this way, a series of plasma treatments are completed.

[0046] <Manufacturing and Regeneration Methods for Upper Electrode Components> Figure 4 is a flowchart showing the manufacturing method of the upper electrode assembly 13. Figure 5 is a flowchart showing the regeneration method of the upper electrode assembly 13.

[0047] As shown in Figure 4, the manufacturing method of the upper electrode assembly 13 according to this embodiment is performed as follows: First, as shown in step S11, an electrode plate 120 and a conductive plate 130 are provided. Then, as shown in step S12, a conductive bonding sheet 140 is sandwiched between the electrode plate 120 and the conductive plate 130. In this state, as shown in step S13, the conductive bonding sheet 140 is melted by a so-called hot pressing or HIP (Hot Isostatic Pressing) method, thereby metal bonding the electrode plate 120 and the conductive plate 130. In this manner, the upper electrode assembly 13 is manufactured.

[0048] Furthermore, as shown in FIG5, the regeneration method of the upper electrode assembly 13 according to this embodiment is performed as follows. First, as shown in step S21, the used upper electrode assembly 13 is recycled. Then, the recycled upper electrode assembly 13 is checked for damage to the conductive plate 130. If it is not damaged, the following steps are performed. That is, as shown in step S22, the used electrode plate 120 (here considered as the first electrode plate) remaining in the recycled upper electrode assembly 13 is removed. The removal of the electrode plate 120 can be performed by mechanical processing such as grinding, or by peeling it off by heating the conductive bonding sheet 140.

[0049] Then, as shown in step S23, the remaining used conductive bonding sheet 140 (here considered as the first conductive bonding sheet) is removed. The removal of the conductive bonding sheet 140 can also be performed by sandblasting. Here, if a conductive coating 139 is formed on the conductive plate 130, the conductive coating 139 can also be removed at the same time.

[0050] Next, as shown in step S24, a new electrode plate 120 (referred to here as the second electrode plate) and a new conductive bonding sheet 140 (referred to here as the second conductive bonding sheet) are prepared. Then, the second conductive bonding sheet 140 is sandwiched between the existing conductive plate 130 and the second electrode plate 120. Then, as shown in step S25, the second conductive bonding sheet 140 is melted by a so-called hot pressing or HIP method, thereby metal bonding the second electrode plate 120 to the existing conductive plate 130. In this way, the upper electrode assembly 13, using the existing conductive plate 130 and having the new electrode plate 120 (second electrode plate), is completed.

[0051] <Shape of Refrigerant Channel> As described above, the conductive plate 130 constituting the upper electrode assembly 13 according to this embodiment has at least one refrigerant channel 131 inside, which adjusts the electrode plate 120, whose temperature changes due to plasma heat input, to a target temperature. The shape or configuration of the refrigerant channel 131 can be arbitrarily designed according to the temperature distribution required by the plasma exposed surface of the electrode plate 120. An example is described below.

[0052] Figures 6-12 are explanatory diagrams showing an example of the specific shape of the refrigerant channel 131. Figures 6-12(a) are diagrams viewed from above. Figure 12(b) is an enlarged view of a portion of the channel viewed in section AA of Figure 12(a). Furthermore, Figures 6-12 illustrate the starting point (S) and ending point (G) of the refrigerant channel 131.

[0053] For example, as shown in Figure 6, the refrigerant channel 131 can have a unidirectional forward shape with the starting point and ending point located at approximately the same position. Alternatively, as shown in Figure 7, it can have a unidirectional forward shape with the starting point and ending point located at different positions. Furthermore, as shown in Figures 8 and 9, it can be constructed as a plurality of concentric circular flow channels, each with a plurality of starting points and ending points (S1~S7, G1~G7). Also, as shown in Figure 10, it can be constructed as a plurality of flow channels with a predetermined geometric shape. Finally, as shown in Figure 11, it can be a radial flow channel.

[0054] Furthermore, as shown in Figure 12, multiple jet-like microchannels can be formed, and refrigerant can be flowed in each channel (refer to the arrows in Figure 12(b)) to regulate the temperature.

[0055] <Effective properties of the technology of this invention> In the above embodiment, the electrode plate 120 and the conductive plate 130 are joined at the upper electrode assembly 13 using, for example, a metal bonding method, i.e., a bonding method using conductive bonding pads 140. This significantly reduces the interfacial thermal resistance caused by the bonding, enabling effective temperature control of the electrode plate 120. Furthermore, since the bonding between the electrode plate 120 and the conductive plate 130 is achieved using a metal bonding method, an electrical contact between the two can be obtained.

[0056] Furthermore, in the above embodiment, the upper electrode assembly 13 is composed of an electrode plate 120, a conductive bonding sheet 140, and a conductive plate 130. The conductive member 10b supports the upper electrode assembly 13 in a manner that allows for arbitrary detachment from the desorption surface 137. Therefore, even if the electrode plate 120 peels off or deteriorates over time during plasma processing, or if etching byproducts adhere to it, necessitating regeneration or replacement, the existing conductive plate 130 can still be reused, and the electrode plate 120 can be easily regenerated or replaced.

[0057] Furthermore, in the upper electrode assembly 13 of the above embodiment, a coolant channel 131 is formed inside the conductive plate 130. This allows for more efficient temperature control of the electrode plate 120 compared to conventional configurations where, for example, the conductive member 10b has a coolant channel inside. Moreover, since the coolant channel 131 is located inside the detachable conductive plate 130, it is possible to "change the shape of the coolant channel 131 using a simple method that allows the member to detach according to the temperature distribution required by the plasma exposure surface of the electrode plate 120."

[0058] The embodiments disclosed in this case should be considered illustrative in all respects, not restrictive. The aforementioned embodiments may be omitted, substituted, or modified in various ways without departing from the scope and intent of the patent application appended to the appendix.

[0059] 1: Plasma treatment device 2: Control Department 2a: Computer 2a1: Processing Department 2a2: Storage Department 2a3: Communication Interface 10: Plasma treatment chamber 10a: Sidewall 10b: Conductive components 10e: Gas exhaust outlet 10s: Plasma processing space 11:Substrate support department 13: Upper electrode assembly 13a: Gas inlet 13b: Gas diffusion space 13c: Gas supply port 111: Ontology Department 111a: Central Region 111b: Annular region 112: Ring Component 113: Base 114: Electrostatic Chuck 120: Electrode plate (second electrode plate) 130: Conductive plate 131: Refrigerant Channel 133:Refrigerant inlet 134: Refrigerant outlet 137: Deattachment surface 139: Conductive coating 140: Conductive bonding sheet (second conductive bonding sheet) 20: Gas Supply Department 21: Gas Source 22: Flow controller 30: Power supply 31: Radio Frequency Power Supply 31a: First radio frequency signal generation unit 31b: Second radio frequency signal generation unit 32: DC power supply 32a: First DC signal generation unit 32b: Second DC signal generation unit 40: Exhaust System S11~S13: Steps S21~S25: Steps G, G1~G7: Finish Line S, S1~S7: starting point W: substrate

Claims

1. A plasma processing apparatus comprising: a plasma processing chamber; a substrate support disposed within the plasma processing chamber; a lower electrode disposed within the substrate support; a conductive member disposed above the substrate support, having at least one refrigerant inlet and at least one refrigerant outlet, and connected to a radio frequency potential or a DC potential; and an upper electrode assembly; the upper electrode assembly comprising: a conductive plate detachably connected to the bottom surface of the conductive member, having one or more refrigerant channels communicating with the at least one refrigerant inlet and the at least one refrigerant outlet; an electrode plate disposed below the conductive plate; and a conductive bonding sheet disposed between the electrode plate and the conductive plate; the conductive bonding sheet being formed of a first conductive material having an Al-Mg alloy or an Al-Si-Mg alloy.

2. The plasma treatment apparatus as claimed in claim 1, wherein, The difference in the coefficient of linear expansion between the conductive plate and the electrode plate is less than 2 ppm / ℃.

3. The plasma processing apparatus as described in claim 1 or 2, wherein, The conductive component is formed of a second conductive material; the conductive plate is formed of a third conductive material that is different from the second conductive material.

4. The plasma treatment apparatus as described in claim 3, wherein, This third conductive material contains Mo.

5. The plasma treatment apparatus as claimed in claim 3, wherein, The second conductive material has Al.

6. The plasma treatment apparatus as described in claim 1 or 2, wherein, The electrode plate is formed of Si or SiC.

7. An upper electrode assembly for use in a plasma processing apparatus, comprising: a conductive plate detachably connected to the plasma processing apparatus and having one or more refrigerant channels; an electrode plate having a plasma exposed surface; and a conductive bonding piece disposed between the electrode plate and the conductive plate; the conductive bonding piece being formed of a first conductive material having an Al-Mg alloy or an Al-Si-Mg alloy.

8. The upper electrode assembly as requested in item 7, wherein, The difference in the coefficient of linear expansion between the conductive plate and the electrode plate is less than 2 ppm / ℃.

9. The upper electrode assembly as requested in item 7 or 8, wherein, The conductive plate is formed of Mo.

10. The upper electrode assembly as requested in item 7 or 8, wherein, The electrode plate is formed of Si or SiC.

11. A method for manufacturing an upper electrode assembly, the upper electrode assembly being used in a plasma processing apparatus; the manufacturing method comprising the following steps: providing an electrode plate and a conductive plate; sandwiching a conductive bonding sheet between the electrode plate and the conductive plate; bonding the electrode plate and the conductive plate by hot pressing or hot equalization at a temperature of 400°C to 1000°C using the conductive bonding sheet; the conductive bonding sheet having an Al-Mg alloy or an Al-Si-Mg alloy.

12. A method for manufacturing the upper electrode assembly as claimed in claim 11, wherein, The conductive plate is formed of Mo.

13. A method for manufacturing the upper electrode assembly as claimed in claim 11 or 12, wherein, The electrode plate is formed of Si or SiC.

14. A method for regenerating an upper electrode assembly used in a plasma processing apparatus; the regeneration method comprising the following steps: providing an upper electrode assembly having: a conductive plate, a first electrode plate, and a first conductive bonding sheet for joining the conductive plate to the first electrode plate; removing the first electrode plate from the upper electrode assembly; removing the first conductive bonding sheet from the upper electrode assembly; sandwiching a second conductive bonding sheet between the conductive plate and the second electrode plate contained in the upper electrode assembly; and joining the second electrode plate to the conductive plate by means of hot pressing or hot equalization at a temperature of 400°C to 1000°C; the second conductive bonding sheet having an Al-Mg alloy or an Al-Si-Mg alloy.

15. The method for regenerating the upper electrode assembly as described in claim 14, wherein, The conductive plate is formed of Mo.

16. A method for regenerating the upper electrode assembly as claimed in claim 14 or 15, wherein, The second electrode plate is formed of Si or SiC.

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