Upper electrode structure and plasma processing device

Abstract

A plasma processing apparatus comprises a plasma processing chamber, a substrate support disposed within the plasma processing chamber and including a lower electrode, and an upper electrode structure disposed above the substrate support, wherein the upper electrode structure comprises a cooling plate having a refrigerant flow path, an electrode plate disposed below the cooling plate, and an electrostatic adsorption film formed on the lower surface of the cooling plate and configured to electrostatically adsorb the electrode plate, wherein the electrostatic adsorption film comprises a dielectric portion and at least one conductive portion formed within the dielectric portion, and a power source electrically connected to the conductive portion.

Description

Technology Field

[0001] An exemplary embodiment of the present disclosure relates to an upper electrode structure and a plasma processing apparatus. Background Technology

[0002] Patent Document 1 discloses an electrostatic chuck that adsorbs an electrode plate in the upper electrode of a plasma processing apparatus. The electrostatic chuck is interposed between the electrode plate and the gas plate. The upper surface of the electrostatic chuck is a contact surface that contacts the lower surface of the gas plate, and the electrostatic chuck is fixed to the lower surface of the gas plate with an adhesive or the like. The lower surface of the electrostatic chuck is an adsorption surface that adsorbs the upper surface of the electrode plate. Prior art literature

[0003] Japanese Patent Publication No. 2020-115419 The problem to be solved

[0004] The present disclosure provides a technology that can efficiently cool an electrode plate. means of solving the problem

[0005] In one exemplary embodiment, a plasma processing apparatus is provided. The plasma processing apparatus comprises a plasma processing chamber, a substrate support, an upper electrode structure, and a power source. The substrate support is disposed within the plasma processing chamber and includes a lower electrode. An upper electrode structure is disposed above the substrate support. The upper electrode structure comprises a cooling plate, an electrode plate, and an electrostatic adsorption film. The cooling plate has a refrigerant flow path. The electrode plate is disposed below the cooling plate. An electrostatic adsorption film is formed on the lower surface of the cooling plate and is configured to electrostatically adsorb the electrode plate. The electrostatic adsorption film has a dielectric portion and at least one conductive portion formed within the dielectric portion. A power source is electrically connected to the conductive portion. Effects of the invention

[0006] According to one exemplary embodiment, the electrode plate can be efficiently cooled. Brief explanation of the drawing

[0007] FIG. 1 is a schematic drawing illustrating a plasma processing apparatus according to one exemplary embodiment. FIG. 2 is a cross-sectional view of an upper electrode according to one exemplary embodiment. FIG. 3 is a cross-sectional view illustrating details of an upper electrode according to one exemplary embodiment. FIG. 4 is a drawing illustrating the lower surface of a cooling plate according to one exemplary embodiment. FIG. 5 is a drawing illustrating an electrode of a cooling plate according to one exemplary embodiment. FIG. 6 is a schematic diagram illustrating a plasma processing apparatus according to another exemplary embodiment. Specific details for implementing the invention

[0008] Various exemplary embodiments are described below.

[0009] In one exemplary embodiment, an upper electrode structure of a plasma processing apparatus is provided. The upper electrode structure comprises an electrode plate and a cooling plate. A gas discharge hole is formed in the electrode plate that penetrates in the thickness direction. The cooling plate supports the electrode plate. The cooling plate has a cooling plate body and an electrostatic adsorption part. The cooling plate body has a flow path through which a refrigerant flows, and is formed such that a gas flow path for supplying processing gas to the gas discharge hole extends in the thickness direction. The electrostatic adsorption part is integrally formed in direct contact with the cooling plate body and is interposed between the electrode plate and the cooling plate body.

[0010] In this upper electrode structure, an electrostatic adsorption part for adsorbing the electrode plate is integrally formed by directly contacting the cooling plate body. Therefore, compared to the case where the electrostatic adsorption part is fixed to the cooling plate body with an adhesive or the like, heat from the electrode plate is efficiently conducted to the cooling plate. Thus, this upper electrode structure can efficiently cool the electrode plate.

[0011] In one exemplary embodiment, the electrostatic adsorption member may have a conductive member among the dielectric members formed by thermal spraying. In this case, the electrostatic adsorption member is integrally formed by direct contact with the cooling plate.

[0012] In one exemplary embodiment, the electrostatic adsorption portion may have a plurality of convex portions in contact with the upper surface of the electrode plate. In this case, a space is formed between the electrostatic adsorption portion and the upper surface of the electrode plate. Accordingly, the upper electrode structure can cool the electrode plate more efficiently, for example, by introducing gas into the space formed between the electrostatic adsorption portion and the electrode plate.

[0013] In one exemplary embodiment, the electrostatic adsorbent may have an annular convex portion that surrounds the entire plurality of convex portions. In this case, for example, gas introduced into the space formed between the electrostatic adsorbent and the electrode plate remains in the space formed between the electrostatic adsorbent and the electrode plate because it is blocked by the annular convex portion even if it attempts to move away from the plurality of convex portions. Because of this, the upper electrode structure can cool the electrode plate more efficiently.

[0014] In one exemplary embodiment, the conductive member may be divided into multiple parts when viewed from the thickness direction. In this case, the electrostatic adsorption member can control the adsorption force for each divided conductive member. The conductive member may be divided into concentric circles. In this case, the electrostatic adsorption member can realize a uniform adsorption force in the in-plane direction with respect to the center of the concentric circle. The electrostatic adsorption member has multiple regions corresponding to the multiple divided conductive members, and the density of the convex portions may differ in the multiple regions. In this case, the electrostatic adsorption member can make the cooling efficiency different for each region corresponding to the divided conductive member.

[0015] In one exemplary embodiment, the gas flow path may be formed at a position that does not overlap with the gas discharge hole when viewed from the thickness direction. When radicals, etc. move linearly from the chamber toward the gas flow path, the radicals collide with the electrostatic adsorption part, thereby avoiding the radicals directly entering the gas flow path. Accordingly, the upper electrode structure can suppress abnormal discharge caused by plasma.

[0016] In one exemplary embodiment, the conductive member may be at least one of alumina and aluminum nitride.

[0017] In one exemplary embodiment, a gas diffusion chamber and a refrigerant flow path may be provided within the main body of the cooling plate. In this case, the cooling plate can cool the upper electrode using a refrigerant. In one exemplary embodiment, the refrigerant flow path may be arranged such that the distance to the lower surface is shorter than the distance to the upper surface of the main body of the cooling plate. In this case, since the refrigerant flow path is positioned near the electrode plate, the cooling plate can efficiently cool the electrode plate. In one exemplary embodiment, a heater may be provided on the periphery of the main body of the cooling plate. In this case, the cooling plate can control the temperature of the cooling plate by heating with the heater. In one exemplary embodiment, the upper electrode structure may have a support member that supports the electrode plate. The locking portion of the support member with respect to the electrode plate may be configured to be rotatable downward.

[0018] In another exemplary embodiment, a plasma processing apparatus is provided. The plasma processing apparatus has a chamber, a substrate support, and an upper electrode structure. The substrate support is configured to support a substrate within the chamber. The upper electrode structure forms the upper part of the chamber. The upper electrode structure comprises an electrode plate and a cooling plate. The electrode plate has a gas discharge hole formed therein penetrating in the thickness direction. The cooling plate supports the electrode plate. The cooling plate has a cooling plate body and an electrostatic adsorption part. The cooling plate body has a flow path through which a refrigerant flows, and is formed such that a gas flow path for supplying processing gas to the gas discharge hole extends in the thickness direction. The electrostatic adsorption part is integrally formed in direct contact with the cooling plate body and is interposed between the electrode plate and the cooling plate body.

[0019] In this upper electrode structure, an electrostatic adsorption part for adsorbing the electrode plate is integrally formed by directly contacting the cooling plate body. Therefore, compared to the case where the electrostatic adsorption part is fixed to the cooling plate body with an adhesive or the like, heat from the electrode plate is efficiently conducted to the cooling plate. Thus, this upper electrode structure can efficiently cool the electrode plate.

[0020] [Overview of Plasma Processing Devices]

[0021] FIG. 1 is a schematic drawing illustrating a plasma processing apparatus according to one exemplary embodiment. The plasma processing apparatus (10) illustrated in FIG. 1 is a capacitively coupled plasma etching apparatus. The plasma processing apparatus (10) comprises a chamber body (12) (an example of a plasma processing chamber). The chamber body (12) has a roughly cylindrical shape and provides an internal space (12s). The chamber body (12) is formed, for example, of aluminum. A plasma-resistant treatment is performed on the inner wall surface of the chamber body (12). For example, an anodic oxidation treatment is performed on the inner wall surface of the chamber body (12). The chamber body (12) is electrically grounded.

[0022] A passage (12p) is formed in the side wall of the chamber body (12). The workpiece passes through the passage (12p) when it is brought into the internal space (12s) and when it is taken out of the internal space (12s). This passage (12p) can be opened and closed by a gate valve (12g).

[0023] A support member (13) is provided on the bottom portion of the chamber body (12). The support member (13) is formed of an insulating material. The support member (13) has a roughly cylindrical shape. The support member (13) extends vertically from the bottom portion of the chamber body (12) within the internal space (12s). The support member (13) supports a stage (14) (an example of a substrate support). The stage (14) is provided within the internal space (12s).

[0024] The stage (14) has a lower electrode (18) and an electrostatic chuck (20). The stage (14) may further have an electrode plate (16). The electrode plate (16) is formed of a conductive material, for example, aluminum, and is roughly disc-shaped. The lower electrode (18) is provided on the electrode plate (16). The lower electrode (18) is formed of a conductive material, for example, aluminum, and is roughly disc-shaped. The lower electrode (18) is electrically connected to the electrode plate (16).

[0025] The electrostatic chuck (20) is provided on the lower electrode (18). A workpiece is mounted on the upper surface of the electrostatic chuck (20). The electrostatic chuck (20) has a main body formed of a dielectric. A film-shaped electrode is provided within the main body of the electrostatic chuck (20). The electrode of the electrostatic chuck (20) is connected to a power source (22) via a switch. The power source (22) may be a DC power source or an AC power source. When voltage from the power source (22) is applied to the electrode of the electrostatic chuck (20), an electrostatic attraction is generated between the electrostatic chuck (20) and the workpiece. Due to the generated electrostatic attraction, the workpiece is pulled toward the electrostatic chuck (20) and held by the electrostatic chuck (20).

[0026] An edge ring (ER) is placed on the stage (14) to surround the edge of the workpiece. The edge ring (ER) is provided to improve the in-plane uniformity of the etching. The edge ring (ER) can be formed of silicon, silicon carbide, or quartz, etc.

[0027] A flow path (18f) is provided inside the lower electrode (18). A refrigerant is supplied to the flow path (18f) via a pipe (26a) from a chiller unit (26) located outside the chamber body (12). The refrigerant supplied to the flow path (18f) returns to the chiller unit (26) via a pipe (26b). In the plasma processing device (10), the temperature of the workpiece mounted on the electrostatic chuck (20) is adjusted by heat exchange between the refrigerant and the lower electrode (18).

[0028] A gas supply line (28) is provided in the plasma processing device (10). The gas supply line (28) supplies heated gas, for example, He gas, from a heated gas supply mechanism between the upper surface of the electrostatic chuck (20) and the lower surface of the workpiece.

[0029] The plasma processing device (10) further comprises an upper electrode (30) (an example of an upper electrode structure). The upper electrode (30) is provided above the stage (14). The upper electrode (30) includes an electrode plate (34). The lower surface of the electrode plate (34) is the lower surface facing the internal space (12s) and forms a partition of the internal space (12s). The electrode plate (34) may be formed of a conductor or semiconductor with low electrical resistance that generates less Joule heat. As an example, the electrode plate (34) is formed of silicon. A plurality of gas discharge holes (34a) are formed in the electrode plate (34). The plurality of gas discharge holes (34a) penetrate the electrode plate (34) in the direction of its thickness.

[0030] A cooling plate (37) that supports the electrode plate (34) is disposed on the upper part of the electrode plate (34). The cooling plate (37) is provided with a cooling plate body part (37A). The cooling plate body part (37A) may be formed of a conductive material such as aluminum. The cooling plate (37) has an electrostatic chuck (35) (an example of an electrostatic adsorption film) on the lower surface of the cooling plate body part (37A). The configuration of the electrostatic chuck (35) will be described later. Due to the adsorption force of the electrostatic chuck (35), the electrode plate (34) is attached to the cooling plate body part (37A). The electrode plate (34) is supported on the upper part of the chamber body (12) by the adsorption force of the electrostatic chuck (35). The member (32) and the locking fixing part (39) (an example of a support member) are support members that support the electrode plate (34) from below to prevent the electrode plate (34) from falling. The member (32) and the locking fixing part (39) are formed from, for example, an insulating material. The locking fixing part (39) may be configured to be rotatable downward.

[0031] A flow path (37c) (an example of a refrigerant flow path) is provided inside the cooling plate main body (37A). Refrigerant is supplied to the flow path (37c) from a chiller unit (not shown) located outside the chamber main body (12). The refrigerant supplied to the flow path (37c) is returned to the chiller unit. By doing so, the temperature of the cooling plate main body (37A) is adjusted. In the plasma processing device (10), the temperature of the electrode plate (34) is adjusted by heat exchange with the cooling plate main body (37A).

[0032] Inside the cooling plate main body (37A), a plurality of gas introduction channels (37a) (an example of a first gas flow channel) are provided to extend downward. Between the upper surface of the electrode plate (34) and the lower surface of the cooling plate main body (37A), a plurality of gas diffusion chambers (37b) are provided corresponding to the plurality of gas introduction channels (37a). Additionally, a plurality of gas supply channels (37e) (an example of a second gas flow channel) are provided to extend in the thickness direction from the gas diffusion chambers (37b) toward the electrode plate (34). The gas supply channels (37e) supply processing gas to a plurality of gas discharge holes (34a) of the electrode plate (34). A plurality of gas introduction ports (37d) are formed in the cooling plate main body (37A) to guide processing gas to the plurality of gas diffusion chambers (37b). A gas supply pipe (38) is connected to the gas introduction ports (37d).

[0033] A gas supply unit (GS) is connected to the gas supply pipe (38). In one embodiment, the gas supply unit (GS) includes a gas source group (40), a valve group (42), and a flow controller group (44). The gas source group (40) is connected to the gas supply pipe (38) via the flow controller group (44) and the valve group (42). The gas source group (40) includes a plurality of gas sources. The plurality of gas sources includes a plurality of gas sources that constitute the processing gas used in the method (MT). The valve group (42) includes a plurality of open / close valves. The flow controller group (44) includes a plurality of flow controllers. Each of the plurality of flow controllers is a mass flow controller or a pressure-controlled flow controller. The plurality of gas sources of the gas source group (40) are connected to the gas supply pipe (38) via the corresponding valve of the valve group (42) and the corresponding flow controller of the flow controller group (44).

[0034] In the plasma processing device (10), a shield (46) is detachably provided along the inner wall of the chamber body (12). The shield (46) is also provided on the outer circumference of the support member (13). The shield (46) prevents etching byproducts from adhering to the chamber body (12). The shield (46) is constructed, for example, by coating a ceramic such as Y2O3 onto an aluminum member.

[0035] A baffle plate (48) is provided between the support member (13) and the side wall of the chamber body (12). The baffle plate (48) is constructed, for example, by coating a ceramic such as Y2O3 onto an aluminum member. A plurality of through holes are formed in the baffle plate (48). An exhaust port (12e) is provided below the baffle plate (48) and also at the bottom of the chamber body (12). An exhaust device (50) is connected to the exhaust port (12e) via an exhaust pipe (52). The exhaust device (50) has a pressure control valve and a vacuum pump such as a turbo molecular pump.

[0036] The plasma processing device (10) further comprises a first high-frequency power source (62) and a second high-frequency power source (64). The first high-frequency power source (62) is a power source that generates a first high frequency (high-frequency power) for plasma generation. The frequency of the first high frequency is, for example, a frequency within the range of 27 MHz to 100 MHz. The first high-frequency power source (62) is connected to the lower electrode (18) via a matching device (66) and an electrode plate (16). The matching device (66) has a circuit for matching the output impedance of the first high-frequency power source (62) with the input impedance of the load side (lower electrode (18) side). Additionally, the first high-frequency power source (62) may be connected to the upper electrode (30) via the matching device (66).

[0037] The second high-frequency power source (64) is a power source that generates a second high frequency (another high-frequency power) for introducing ions into the workpiece. The frequency of the second high frequency is lower than the frequency of the first high frequency. The frequency of the second high frequency is, for example, a frequency within the range of 400 kHz to 13.56 MHz. The second high-frequency power source (64) is connected to the lower electrode (18) via a matching device (68) and an electrode plate (16). The matching device (68) has a circuit for matching the output impedance of the second high-frequency power source (64) with the input impedance of the load side (lower electrode (18) side).

[0038] The plasma processing device (10) may further be provided with a DC power supply unit (70) (an example of a DC power supply). The DC power supply unit (70) is connected to an upper electrode (30). The DC power supply unit (70) can generate a DC voltage and apply the DC voltage to the upper electrode (30).

[0039] The plasma processing device (10) may further be equipped with a control unit (Cnt). The control unit (Cnt) may be a computer equipped with a processor, a memory unit, an input device, a display device, etc. The control unit (Cnt) controls each part of the plasma processing device (10). In the control unit (Cnt), using an input device, an operator may execute command input operations, etc., to manage the plasma processing device (10). In addition, the control unit (Cnt) may visualize and display the operating status of the plasma processing device (10) by means of a display device. Furthermore, in the memory unit of the control unit (Cnt), a control program and recipe data for controlling various processes executed in the plasma processing device (10) by a processor are stored. By the processor of the control unit (Cnt) executing the control program and controlling each part of the plasma processing device (10) according to the recipe data, the method described below is executed in the plasma processing device (10).

[0040] [Overview of Upper Electrode Structure]

[0041] FIG. 2 is a cross-sectional view of an upper electrode according to one exemplary embodiment. As shown in FIG. 2, the upper electrode (30) has a structure in which an electrode plate (34) and a cooling plate (37) are stacked in order from bottom to top. On the lower surface of the cooling plate body (37A), an electrostatic chuck (35) is integrally formed by directly contacting the cooling plate body (37A). As an example, the electrostatic chuck (35) is formed on the cooling plate (37) by thermal spraying. The lower surface of the electrostatic chuck (35) is an adsorption surface that adsorbs the upper surface of the electrode plate (34). In this way, the electrostatic chuck (35) is interposed between the electrode plate (34) and the cooling plate (37).

[0042] FIG. 3 is a cross-sectional view illustrating the details of an upper electrode according to one exemplary embodiment. As shown in FIG. 3, the electrostatic chuck (35) has a main body (35a) (an example of a dielectric part) made of a dielectric. The dielectric is made of at least one of alumina (Al2O3) and aluminum nitride (AlN). Inside the main body (35a), at least one electrode (35b) (an example of a conductive part) is provided. That is, the electrostatic chuck (35) has an electrode (35b) in the main body (35a) formed by thermal spraying. The electrode (35b) is electrically connected to a power source (35p). The power source (35p) may be a DC power source or an AC power source. When a voltage from the power source (35p) is applied to the electrode (35b) of the electrostatic chuck (35), an electrostatic attraction is generated between the electrostatic chuck (35) and the electrode plate (34). Due to the generated electrostatic force, the electrode plate (34) is attracted to the electrostatic chuck (35) and is held by the electrostatic chuck (35).

[0043] The electrostatic chuck (35) has a through hole extending in the thickness direction at a position corresponding to the gas supply channel (37e) of the cooling plate (37). By doing so, the processing gas present in the gas diffusion chamber (37b) passes through the gas supply channel (37e) and passes through the through hole of the electrostatic chuck (35) to be supplied to the upper surface of the electrode plate (34).

[0044] On the lower surface (adsorption surface) of the electrostatic chuck (35), a plurality of convex portions (35c) (an example of a dot-shaped convex portion) are formed. Because of this, the front surface of the electrostatic chuck (35) is not in close contact with the electrode plate (34), but only the leading edge surfaces of the plurality of convex portions (35c) come into contact with the upper surface of the electrode plate (34). The plurality of convex portions (35c) form a dot pattern, for example. Additionally, an annular convex portion (35d) that surrounds the entirety of the plurality of convex portions (35c) may be provided at the outermost periphery of the plurality of convex portions (35c).

[0045] A through hole as described above is formed between the plurality of convex portions (35c) of the electrostatic chuck (35). That is, the gas supply channel (37e) is provided at a position that does not overlap with the plurality of convex portions (35c) when viewed from the thickness direction of the cooling plate main body (37A). In addition, the gas supply channel (37e) is formed at a position that does not overlap with the gas discharge hole (34a) of the electrode plate (34) when viewed from the thickness direction of the cooling plate main body (37A). That is, the first axis line (AX1) of the gas supply channel (37e) and the second axis line (AX2) of the gas discharge hole (34a) are offset from each other. Accordingly, the processing gas supplied from the gas supply channel (37e) is initially concentrated between the plurality of convex portions (35c) of the electrostatic chuck (35), and then discharged from the gas discharge hole (34a). By providing such an offset structure, it is possible to physically obstruct the movement of radicals or gases in the internal space (12s) from the gas discharge hole (34a) to the gas supply path (37e) of the cooling plate (37). By doing so, the offset structure can suppress abnormal discharge from occurring in the gas supply path (37e) of the cooling plate (37).

[0046] The electrode (35b) may be divided into multiple concentric circles when viewed from the thickness direction of the cooling plate body (37A). For example, the electrode (35b) has a central electrode located in the center and an outer electrode arranged to surround the central electrode. Power is connected to each of the central electrode and the outer electrode. By doing so, different adsorption forces are exerted in the central region and the outer region, thereby realizing different temperature control in the central region and the outer region. In addition, the electrostatic chuck (35) may have multiple regions corresponding to the electrodes (35b) that are divided into multiple parts. Also, the density of the multiple convex parts (35c) may be different for each region.

[0047] FIG. 4 is a drawing illustrating the lower surface of a cooling plate according to one exemplary embodiment. FIG. 5 is a drawing illustrating the electrode of a cooling plate according to one exemplary embodiment. As shown in FIG. 4, an electrostatic chuck (35) having a plurality of convex portions (35c) is formed on the lower surface of the cooling plate body portion (37A). As shown in FIG. 5, the polarity of the voltage supplied to the central electrode (352b) corresponding to the central region (Z1) (an example of a first region) may be a voltage of a different polarity from the polarity of the voltage supplied to the outer electrode (351b) corresponding to the outer region (Z2) (an example of a second region). In this case, the electrostatic chuck (35) adsorbs the electrode plate (34) in a bipolar manner. In the bipolar manner, it is preferable that there be a potential difference between the central electrode (352b) and the outer electrode (351b). The polarity of the voltage supplied to the central electrode (352b) corresponding to the central region (Z1) may be the same as the polarity of the voltage supplied to the outer electrode (351b) corresponding to the outer region (Z2). In this case, the electrostatic chuck (35) adsorbs the electrode plate (34) in a single-polarity manner.

[0048] [Method for separating electrode plates]

[0049] When the electrode plate (34) is separated, the applied voltage of the power supply connected to the electrostatic chuck (35) is set to 0V, and at the same time, processing gas is output from the gas supply unit (GS). As a result, the electrode plate (34) is pressed in a direction separated from the electrostatic chuck (35) by the pressure of the processing gas, so the separation of the electrode plate (34) becomes easy.

[0050] [Summary of Exemplary Implementations]

[0051] The upper electrode (30) is integrally formed by the electrostatic chuck (35) for adsorbing the electrode plate (34) directly contacting the cooling plate body (37A) by thermal spraying. Because of this, compared to the case where the electrostatic chuck (35) is fixed to the cooling plate body (37A) with an adhesive or the like, the heat of the electrode plate (34) is efficiently conducted to the cooling plate body (37A). Therefore, this upper electrode (30) can efficiently cool the electrode plate (34).

[0052] In the upper electrode (30), since the electrostatic chuck (35) has a plurality of convex portions (35c) that contact the upper surface of the electrode plate (34), a space is formed between the electrostatic chuck (35) and the upper surface of the electrode plate (34). And, by allowing a processing gas to flow into the space formed between the electrostatic chuck (35) and the electrode plate (34), the electrode plate (34) can be cooled more efficiently.

[0053] Since the multiple convex portions (35c) of the electrostatic chuck (35) form a dot pattern, the processing gas is uniformly diffused across the entire upper surface of the electrode plate (34). Because of this, the upper electrode (30) can uniformly cool the entire electrode plate (34).

[0054] In the upper electrode (30), the gas supply channel (37e) of the cooling plate (37) is formed at a position that does not overlap with the gas discharge hole (34a) when viewed from the thickness direction. When radicals move linearly from the chamber toward the gas supply channel (37e), the radicals collide with the electrostatic chuck (35). Therefore, it is possible to avoid the radicals directly entering the gas supply channel (37e). Because of this, the upper electrode (30) can suppress abnormal discharge caused by plasma.

[0055] [Other exemplary embodiments]

[0056] FIG. 6 is a schematic diagram illustrating a plasma processing apparatus according to another exemplary embodiment. The plasma processing apparatus (10) illustrated in FIG. 6 differs from the plasma processing apparatus (10) illustrated in FIG. 1 in that it is equipped with a flow path (37c) within a cooling plate body (37A) and heaters (60, 61), except otherwise it is identical. The following description focuses on the differences, and redundant descriptions are omitted.

[0057] As shown in FIG. 6, the flow path (37c) is positioned below the gas diffusion chamber (37b). The flow path (37c) is positioned so that the distance to the lower surface is shorter than the distance to the upper surface of the cooling plate body (37A). By doing so, the flow path (37c) is positioned near the electrode plate (34), thereby increasing the cooling effect.

[0058] A heater (60) is provided on the upper surface of the cooling plate main body (37A). An example of the heater (60) is a sheet heater. A heater (61) is provided on the peripheral portion of the cooling plate main body (37A). An example of the heater (61) is a ceramic heater. By providing the heaters (60, 61), the temperature uniformity within the surface of the electrode plate (34) can be improved.

[0059] Although various exemplary embodiments have been described above, the invention is not limited to the aforementioned exemplary embodiments and may be subject to various omissions, substitutions, and modifications. Furthermore, it is possible to form other embodiments by combining elements from different embodiments.

[0060] For example, the plasma treatment device (10) is a capacitively coupled plasma treatment device, but a plasma treatment device according to other embodiments may be a different type of plasma treatment device. Such a plasma treatment device may be any type of plasma treatment device. Examples of such a plasma treatment device include an inductively coupled plasma treatment device and a plasma treatment device that generates plasma by surface waves such as microwaves.

[0061] Additionally, although an example has been shown in which two high-frequency power sources are connected to the lower electrode (18) and a DC power supply unit (70) is connected to the upper electrode (30), the plasma treatment device (10) is not limited thereto. For example, the plasma treatment device (10) may not be equipped with an upper electrode (30). For example, the plasma treatment device (10) may have high-frequency power sources connected to the lower electrode (18) and the upper electrode (30). Additionally, the plasma treatment device (10) shown in FIG. 1 may be provided with a heater (60, 61) shown in FIG. 6.

[0062] In the foregoing description, various embodiments of the present disclosure are described herein for illustrative purposes only, and it will be understood that various modifications can be made without departing from the scope and common knowledge of the present disclosure. Accordingly, the various embodiments disclosed herein are not intended to be limiting, and the true scope and common knowledge are indicated by the appended claims. Explanation of the symbols

[0063] 10: Plasma treatment device 30: Upper electrode 34: Electrode plate 34a: Gas discharge hole 35: Electrostatic chuck (an example of an electrostatic adsorption film) 37: Cooling plate 37A: Cooling plate main body

Claims

Claim 1 A plasma processing apparatus comprising: a plasma processing chamber; a substrate support disposed within the plasma processing chamber and including a lower electrode; an upper electrode structure disposed above the substrate support, wherein the upper electrode structure comprises a cooling plate having a refrigerant flow path, an electrode plate disposed below the cooling plate, and an electrostatic adsorption film integrally formed by thermal spraying on the lower surface of the cooling plate and configured to electrostatically adsorb the electrode plate, wherein the electrostatic adsorption film comprises a dielectric portion and at least one conductive portion formed within the dielectric portion; and a power source electrically connected to the conductive portion. Claim 2 In claim 1, the electrostatic adsorption film is a plasma treatment device that is a thermal spray film. Claim 3 A plasma processing apparatus comprising: a plasma processing chamber; a substrate support disposed within the plasma processing chamber and including a lower electrode; an upper electrode structure disposed above the substrate support, wherein the upper electrode structure comprises a cooling plate having a refrigerant flow path, an electrode plate disposed below the cooling plate, and an electrostatic adsorption film formed on the lower surface of the cooling plate and configured to electrostatically adsorb the electrode plate, wherein the electrostatic adsorption film comprises a dielectric portion and at least one conductive portion formed within the dielectric portion; and a power source electrically connected to the conductive portion, wherein the electrostatic adsorption film comprises a plurality of point-shaped convex portions in contact with the upper surface of the electrode plate. Claim 4 In claim 3, the electrostatic adsorption film contacts the upper surface of the electrode plate and is a plasma processing device having an annular convex portion surrounding the plurality of point-shaped convex portions. Claim 5 In claim 4, the plasma processing apparatus wherein at least one conductive part comprises a plurality of conductive parts. Claim 6 In claim 5, the plurality of conductive parts are annular and arranged in a concentric shape in a plasma processing apparatus. Claim 7 In claim 6, the plurality of point-shaped convex portions include a plurality of first point-shaped convex portions disposed in a first region that overlaps with a first conductor portion among the plurality of conductor portions when viewed in a plane, and a plurality of second point-shaped convex portions disposed in a second region that overlaps with a second conductor portion among the plurality of conductor portions when viewed in a plane, wherein the density of the plurality of second point-shaped convex portions in the second region is different from the density of the plurality of first point-shaped convex portions in the first region, a plasma processing apparatus. Claim 8 A plasma processing chamber; a substrate support disposed within the plasma processing chamber and including a lower electrode; and an upper electrode structure disposed above the substrate support, wherein the upper electrode structure comprises a cooling plate having a refrigerant flow path, an electrode plate disposed below the cooling plate, and an electrostatic adsorption film formed on the lower surface of the cooling plate and configured to electrostatically adsorb the electrode plate, wherein the electrostatic adsorption film comprises a dielectric portion and at least one conductive portion formed within the dielectric portion, and a power source electrically connected to the conductive portion; wherein the cooling plate comprises a gas diffusion chamber, a first gas flow path extending from the upper surface of the cooling plate to the gas diffusion chamber, and a plurality of second gas flow paths extending from the gas diffusion chamber to the lower surface of the cooling plate; wherein the electrode plate comprises a plurality of gas discharge holes communicating with the plurality of second gas flow paths, and wherein the plurality of second gas flow paths are located at positions that do not overlap with the plurality of gas discharge holes when viewed from a planar perspective. Plasma treatment device being formed. Claim 9 In claim 1, the dielectric portion is formed from at least one of alumina and aluminum nitride in a plasma treatment apparatus. Claim 10 In claim 8, the plasma treatment device wherein the gas diffusion chamber is formed at a position lower than the refrigerant path. Claim 11 In claim 8, the plasma treatment device wherein the gas diffusion chamber is formed at a position higher than the refrigerant path. Claim 12 A plasma processing apparatus comprising: a plasma processing chamber; a substrate support disposed within the plasma processing chamber and including a lower electrode; an upper electrode structure disposed above the substrate support, wherein the upper electrode structure comprises a cooling plate having a refrigerant flow path, an electrode plate disposed below the cooling plate, and an electrostatic adsorption film formed on the lower surface of the cooling plate and configured to electrostatically adsorb the electrode plate, wherein the electrostatic adsorption film comprises a dielectric portion and at least one conductive portion formed within the dielectric portion; and a heater disposed on the peripheral portion of the cooling plate and having a power source electrically connected to the conductive portion. Claim 13 A plasma processing apparatus further comprising: a plasma processing chamber; a substrate support disposed within the plasma processing chamber and including a lower electrode; an upper electrode structure disposed above the substrate support, wherein the upper electrode structure comprises a cooling plate having a refrigerant flow path, an electrode plate disposed below the cooling plate, and an electrostatic adsorption film formed on the lower surface of the cooling plate and configured to electrostatically adsorb the electrode plate, wherein the electrostatic adsorption film comprises a dielectric portion and at least one conductive portion formed within the dielectric portion; and a support member configured to support the electrode plate and having a power source electrically connected to the conductive portion. Claim 14 An upper electrode structure used in a plasma processing apparatus, comprising: a cooling plate having a refrigerant flow path; an electrode plate disposed below the cooling plate; and an electrostatic adsorption film integrally formed by thermal spraying on the lower surface of the cooling plate and configured to electrostatically adsorb the electrode plate, wherein the electrostatic adsorption film has a dielectric portion and at least one conductive portion formed within the dielectric portion. Claim 15 In claim 14, the electrostatic adsorption film is an upper electrode structure having a plurality of point-shaped convex portions in contact with the upper surface of the electrode plate. Claim 16 In claim 14 or 15, the cooling plate has a gas diffusion chamber, a first gas path extending from the upper surface of the cooling plate to the gas diffusion chamber, and a plurality of second gas paths extending from the gas diffusion chamber to the lower surface of the cooling plate, and the electrode plate has a plurality of gas discharge holes communicating with the plurality of second gas paths, and the plurality of second gas paths are formed at a position that does not overlap with the plurality of gas discharge holes when viewed from a planar view, forming an upper electrode structure. Claim 17 In claim 14, an upper electrode structure further comprising a heater disposed in a peripheral portion of the cooling plate. Claim 18 In claim 14, an upper electrode structure further comprising a support member configured to support the electrode plate.

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