Substrate processing apparatus and substrate processing method

Abstract

To adsorb and desorb a substrate stably to and from an electrostatic chuck controlled at high temperature.SOLUTION: An electrostatic chuck for chucking a substrate, which includes a dielectric and an adsorption electrode for adsorbing the substrate inside the dielectric, a heater electrode for heating the substrate, an adsorption power source for applying an adsorption voltage to adsorb the substrate to the adsorption electrode, and a heater power source for applying a heater voltage to heat the substrate to the heater electrode are provided. The adsorption power source controls the level of the adsorption voltage to be applied to the adsorption electrode on the basis of the level of the heater voltage.SELECTED DRAWING: Figure 3A

Description

[Technical Field]

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

[0002] Patent Document 1 discloses an electrostatic chuck that includes a dielectric layer that attracts a substrate to be processed and a heat insulating plate stacked together, and the top and side surfaces of the heat insulating plate facing the dielectric layer are covered with a conductive film for evading charged electric charges. According to the electrostatic chuck disclosed in Patent Document 1, the dielectric layer is made of alumina ceramic or the like for attracting the substrate to be processed by utilizing electrostatic force. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2013-016554 Summary of the Invention [Problem to be solved by the invention]

[0004] The technology according to the present disclosure performs stable attraction and desorption of a substrate to and from an electrostatic chuck controlled to a high temperature. [Means for solving the problem]

[0005] One aspect of the present disclosure is A substrate support, An electrostatic chuck for attracting a substrate, the electrostatic chuck including a dielectric and an attraction electrode for attracting a substrate inside the dielectric, a heater electrode for heating the substrate, an attraction power supply for applying an attraction voltage to the attraction electrode for attracting the substrate, and a heater power supply for applying a heater voltage to the heater electrode for heating the substrate, a plurality of temperature control regions each including the chucking electrode and the heater electrode; The suction power supply is While the substrate is being processed in a state in which the substrate is heated by the heater electrode, for each of the plurality of temperature control regions, The magnitude of the attraction voltage to be applied to the attraction electrode is determined based on the magnitude of the heater voltage. each Controlling, substrate support. [Effects of the Invention]

[0006] According to the present disclosure, a substrate can be stably attracted to and desorbed from an electrostatic chuck controlled to a high temperature. [Brief explanation of the drawings]

[0007] [Figure 1A] 10 is a graph illustrating the relationship between the substrate chucking time and the amount of charge transfer when the electrostatic chuck is controlled to a room temperature. [Figure 1B] 10 is a graph illustrating the relationship between the substrate chucking time and the amount of charge transfer when the electrostatic chuck is controlled to a high temperature. [Figure 2] 1 is a vertical cross-sectional view showing an example of the configuration of a plasma processing system according to the present disclosure. [Figure 3A] 1 is a longitudinal sectional view showing an outline of the configuration of a substrate support according to a first embodiment. [Figure 3B] 1 is a cross-sectional view showing an outline of the configuration of a substrate support according to a first embodiment. [Figure 4A] 10 is a graph illustrating the relationship between the temperature of an electrostatic chuck and the amount of charge transfer in the radial direction of the electrostatic chuck when the attracting voltage is kept constant. [Figure 4B] 10 is a graph illustrating the relationship between the temperature of the electrostatic chuck and the amount of charge transfer when the attraction voltage is changed in the radial direction of the electrostatic chuck. [Figure 5] FIG. 10 is an explanatory diagram illustrating a configuration example of a plasma processing system according to another embodiment. [Figure 6A] FIG. 10 is a longitudinal sectional view showing an outline of the configuration of a substrate support according to a second embodiment. [Figure 6B] FIG. 10 is a cross-sectional view showing an outline of the configuration of a substrate support according to a second embodiment. [Figure 6C] 10A and 10B are explanatory diagrams showing the relationship between the chucking time and the amount of charge transfer when a DC voltage is applied to the chucking electrode of the electrostatic chuck and when an AC voltage is applied to the chucking electrode of the electrostatic chuck. [Figure 7A]10 is a graph showing the relationship between time and attraction voltage when the phase difference between attraction voltages applied to each attraction electrode is 0° in the substrate support according to the second embodiment. [Figure 7B] 10 is a graph showing the relationship between time and attraction voltage when the phase difference between attraction voltages applied to each attraction electrode is 30° in the substrate support according to the second embodiment. [Figure 7C] 10 is a graph showing the relationship between time and attraction voltage when the phase difference between attraction voltages applied to each attraction electrode is 60° in the substrate support according to the second embodiment. [Figure 7D] 10 is a graph showing the relationship between time and attraction voltage when the phase difference between attraction voltages applied to each attraction electrode is 90° in the substrate support according to the second embodiment. [Figure 7E] 10 is a graph showing the relationship between time and attraction voltage when the phase difference between attraction voltages applied to each attraction electrode is 180° in the substrate support according to the second embodiment. [Figure 8] FIG. 10 is an explanatory diagram showing a modified example of the plasma processing system according to the second embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0008] In a semiconductor device manufacturing process, an etching process is performed on a layer to be etched (e.g., a silicon-containing film) formed by stacking on the surface of a semiconductor substrate (hereinafter simply referred to as "substrate") using a mask layer (e.g., a resist film) on which a pattern has been formed in advance as a mask. This etching process is generally performed in a plasma processing apparatus equipped with an electrostatic chuck that attracts and holds the substrate by using electrostatic force.

[0009] As the electrostatic chuck, a Coulomb-type electrostatic chuck may be used, as disclosed in Patent Document 1. A DC voltage is usually applied to a Coulomb-type electrostatic chuck, and in order to achieve stable attraction and desorption of a substrate, it is required to maintain the volume resistivity of the electrostatic chuck at a desired value or higher, for example, 1e+15 cmΩ or higher.

[0010] In recent years, changes in mask layer materials have led to an increasing demand for substrate processing using electrostatic chucks at high temperatures. As shown in Figure 1A, the volume resistivity of an electrostatic chuck is high at room temperature, resulting in a gradual charge transfer rate over time, ensuring proper polarization between the substrate and the electrostatic chuck. In contrast, as shown in Figure 1B, the volume resistivity of an electrostatic chuck decreases at high temperatures, resulting in a steeper charge transfer rate over time. As a result, proper polarization between the substrate and the electrostatic chuck cannot be maintained, and the residual charge can make stable chuck and dechuck difficult. The effect of this residual charge begins to appear when the electrostatic chuck temperature reaches approximately 200°C and becomes significant above 250°C.

[0011] Although JR (Johnson-Rahbek) type electrostatic chucks are available as electrostatic chucks that can withstand high temperatures, it is difficult to control the residual adhesion with JR type electrostatic chucks, and because the volume resistivity changes significantly with temperature, it is not possible to perform room temperature processing and high temperature processing consecutively. In other words, there is room for improvement in conventional electrostatic chucks, and it is necessary to control the electrostatic chuck so that it can stably attract and desorb substrates even at high temperatures.

[0012] The technology disclosed herein has been developed in consideration of the above circumstances, and provides a method for stably adsorbing and desorbing a substrate using an electrostatic chuck controlled at a high temperature. Hereinafter, a plasma processing system and a plasma processing method according to the present disclosure will be described with reference to the drawings. Note that in this specification and the drawings, elements having substantially the same functional configurations are designated by the same reference numerals, and redundant description will be omitted.

[0013] <Plasma processing equipment> First, a plasma processing system according to the present disclosure will be described. Fig. 2 is a schematic cross-sectional view showing an example of a plasma processing system according to the present disclosure.

[0014] The plasma processing system includes a capacitively coupled plasma processing device 1 and a controller 2. The plasma processing device 1 includes a plasma processing chamber 10, a gas supply 20, a power supply 30, and an exhaust system 40. The plasma processing device 1 also includes a substrate support 11 and a gas inlet. The substrate support 11 is disposed within the plasma processing chamber 10. The gas inlet is configured to introduce at least one process gas into the plasma processing chamber 10. The gas inlet includes a showerhead 13. The showerhead 13 is disposed above the substrate support 11. In one embodiment, the showerhead 13 forms at least a portion of the ceiling of the plasma processing chamber 10. Within the plasma processing chamber 10, a plasma processing space 10s is defined by the showerhead 13, a sidewall 10a of the plasma processing chamber 10, and the substrate support 11. The plasma processing chamber 10 has at least one gas inlet for supplying at least one process gas to the plasma processing space 10s and at least one gas outlet for exhausting gas from the plasma processing space 10s. The plasma processing chamber 10, including the sidewall 10a, is grounded. The showerhead 13 and the substrate support 11 are electrically isolated from the plasma processing chamber 10.

[0015] The substrate support 11 includes a main body 111 and a ring assembly 112. The main body 111 has a substrate support surface 111a for supporting a substrate (wafer) W and a ring support surface 111b for supporting the ring assembly 112. The ring support surface 111b of the main body 111 surrounds the substrate support surface 111a of the main body 111 in a plan view. The substrate W is disposed on the substrate support surface 111a of the main body 111, and the ring assembly 112 is disposed on the ring support surface 111b of the main body 111 so as to surround the substrate W on the substrate support surface 111a of the main body 111. 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 includes a dielectric material such as ceramics and an attraction electrode disposed within the dielectric material. The electrostatic chuck 114 is disposed on a base 113. The upper surface of the electrostatic chuck 114 has a substrate support surface 111a. The ring assembly 112 includes one or more annular members. At least one of the one or more annular members is an edge ring. Although not shown, the substrate support 11 also includes a temperature control module configured to adjust at least one of the electrostatic chuck 114, the ring assembly 112, and the substrate W to a target temperature. The temperature control module includes a heater, a heat transfer medium, and a flow path. A heat transfer fluid such as brine or gas flows through the flow path. The substrate support 11 may also include a heat transfer gas supply unit configured to supply a heat transfer gas between the back surface of the substrate W and the substrate support surface 111a.

[0016] The detailed configuration of the substrate support 11 according to the embodiment will be described later.

[0017] The showerhead 13 is configured to introduce at least one processing gas from the gas supply unit 20 into the plasma processing space 10s. The showerhead 13 has at least one gas supply port 13a, at least one gas diffusion chamber 13b, and multiple gas inlets 13c. The processing gas supplied from the gas supply unit 20 to the gas supply port 13a passes through the gas diffusion chamber 13b and is introduced into the plasma processing space 10s from the multiple gas inlets 13c. The showerhead 13 also includes a conductive member. The conductive member of the showerhead 13 functions as an upper electrode. In addition to the showerhead 13, the gas inlet may also include one or more side gas injectors (SGIs) attached to one or more openings formed in the sidewall 10a.

[0018] 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 is configured to supply at least one process gas from a corresponding gas source 21 to the showerhead 13 via a corresponding flow controller 22. Each flow controller 22 may include, for example, a mass flow controller or a pressure-controlled flow controller. Additionally, the gas supply unit 20 may include one or more flow modulation devices to modulate or pulse the flow rate of the at least one process gas.

[0019] 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 is configured to supply at least one RF signal (RF power), such as a source RF signal and a bias RF signal, to a conductive member (lower electrode) of the substrate support 11 and / or a conductive member (upper electrode) of the showerhead 13. This generates a plasma from at least one process gas supplied to the plasma processing space 10s. Therefore, the RF power supply 31 can function as at least a part of a plasma generating unit configured to generate a plasma from one or more process gases in the plasma processing chamber 10. In addition, supplying a bias RF signal to the lower electrode generates a bias potential on the substrate W, thereby attracting ion components in the formed plasma to the substrate W.

[0020] In one embodiment, the RF power supply 31 includes a first RF generating unit 31a and a second RF generating unit 31b. The first RF generating unit 31a is coupled to the lower electrode and / or the upper electrode via at least one impedance matching circuit and is configured to generate a source RF signal (source RF power) for plasma generation. In one embodiment, the source RF signal has a frequency in the range of 13 MHz to 150 MHz. In one embodiment, the first RF generating unit 31a may be configured to generate multiple source RF signals having different frequencies. The generated one or more source RF signals are supplied to the lower electrode and / or the upper electrode. The second RF generating unit 31b is coupled to the lower electrode via at least one impedance matching circuit and is configured to generate a bias RF signal (bias RF power). In one embodiment, the bias RF signal has a lower frequency than the source RF signal. In one embodiment, the bias RF signal has a frequency in the range of 400 kHz to 13.56 MHz. In one embodiment, the second RF generating unit 31b may be configured to generate multiple bias RF signals having different frequencies. The generated one or more bias RF signals are provided to the lower electrode, and in various embodiments, at least one of the source RF signal and the bias RF signal may be pulsed.

[0021] The power supply 30 may also include a DC power supply 32 coupled to the plasma processing chamber 10. The DC power supply 32 includes a first DC generator 32a and a second DC generator 32b. In one embodiment, the first DC generator 32a is connected to the lower electrode and configured to generate a first DC signal. The generated first DC signal is applied to the lower electrode. In one embodiment, the first DC signal may be applied to another electrode, such as an electrode in an electrostatic chuck. In one embodiment, the second DC generator 32b is connected to 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. Note that the first and second DC generators 32a and 32b may be provided in addition to the RF power supply 31, or the first DC generator 32a may be provided instead of the second RF generator 31b.

[0022] The exhaust system 40 may be connected to, for example, a gas exhaust port 10e provided at the bottom of the plasma processing chamber 10. The exhaust system 40 may include a pressure regulating valve and a vacuum pump. The pressure regulating valve regulates the internal pressure of the plasma processing space 10s. The vacuum pump may include a turbomolecular pump, a dry pump, or a combination thereof.

[0023] The controller 2 processes computer-executable instructions that cause the plasma processing apparatus 1 to perform various processes described in this disclosure. The controller 2 may be configured to control each element of the plasma processing apparatus 1 to perform various processes described herein. In one embodiment, part or all of the controller 2 may be included in the plasma processing apparatus 1. The controller 2 may include, for example, a computer 2a. The computer 2a may include, for example, a processing unit (CPU: Central Processing Unit) 2a1, a storage unit 2a2, and a communication interface 2a3. The processing unit 2a1 may be configured to perform various control operations based on programs stored in the storage unit 2a2. The storage unit 2a2 may include a random access memory (RAM), a read-only memory (ROM), a hard disk drive (HDD), a solid state drive (SSD), or a combination thereof. The communication interface 2a3 may communicate with the plasma processing apparatus 1 via a communication line such as a local area network (LAN).

[0024] Although various exemplary embodiments have been described above, the present invention is not limited to the above-described exemplary embodiments, and various additions, omissions, substitutions, and modifications may be made. Furthermore, elements in different embodiments may be combined to form other embodiments.

[0025] <Substrate Support According to First Embodiment> The configuration of the substrate support body according to the first embodiment will be described below. Fig. 3A is a vertical cross-sectional view showing the configuration of the substrate support body 11 according to the first embodiment. Fig. 3B is a horizontal cross-sectional view showing the AA cross-section in Fig. 3A.

[0026] The electrostatic chuck 114 is provided therein with at least a central heater electrode 115a and a peripheral heater electrode 115b configured to adjust the electrostatic chuck 114 to a target temperature. The electrostatic chuck 114 also is provided therein with a central chucking electrode 116a and a peripheral chucking electrode 116b for chucking and holding the substrate W on the substrate support surface 111a, on the upper surface side (substrate W side) of the central heater electrode 115a and the peripheral heater electrode 115b. The electrostatic chuck 114 is configured as a Coulomb-type electrostatic chuck in which the central heater electrode 115a, the peripheral heater electrode 115b, the central chucking electrode 116a, and the peripheral chucking electrode 116b are sandwiched between dielectrics.

[0027] As shown in FIG. 3B, in a plan view, the substrate support surface 111a of the electrostatic chuck 114 includes a first temperature control region Z1 formed radially inward and a second temperature control region Z2 formed to surround the first temperature control region Z1.

[0028] The central heater electrode 115a is provided below (on the base 113 side) the central chucking electrode 116a (AA cross section) at a position corresponding to the first temperature control zone Z1. The peripheral heater electrode 115b is provided below the peripheral chucking electrode 116b (AA cross section) at a position corresponding to the second temperature control zone Z2. That is, the electrostatic chuck 114 of the first embodiment is configured to be able to independently adjust the temperature of the substrate W for each of the plurality of temperature control zones Z (for each of two temperature control zones Z in the example shown in FIG. 3A).

[0029] In one example, a heater power supply (not shown) is connected to each of the central heater electrode 115a and the peripheral heater electrode 115b, and a heater voltage is applied to each of the heater electrodes from each heater power supply. In another example, a single heater power supply is connected to each of the central heater electrode 115a and the peripheral heater electrode 115b, and a heater voltage is applied to each of the heater electrodes from the heater power supply. In either case, the heater voltages applied to the central heater electrode 115a and the peripheral heater electrode 115b from the heater power supply are configured to be independently controllable. The application of the heater voltage from the heater power supply heats the central heater electrode 115a and the peripheral heater electrode 115b, thereby heating the electrostatic chuck 114 and the substrate W held on the substrate support surface 111a.

[0030] The central attraction electrode 116a is provided corresponding to the first temperature control zone Z1. The peripheral attraction electrode 116b is provided corresponding to the second temperature control zone Z2. That is, the electrostatic chuck 114 of the first embodiment is configured to be able to apply an attraction voltage for the substrate W independently to each of the plurality of temperature control zones Z (each of two temperature control zones Z in the example shown in FIGS. 3A and 3B).

[0031] In one example, an adsorption power supply 117 is connected to each of the central adsorption electrode 116a and the peripheral adsorption electrode 116b, and an adsorption voltage is applied to each of the adsorption electrodes from each of the adsorption power supplies. In another example, a single adsorption power supply 117 is connected to each of the central adsorption electrode 116a and the peripheral adsorption electrode 116b, and an adsorption voltage is applied to each of the adsorption electrodes from the adsorption power supply 117. In either case, the adsorption voltages applied to the central adsorption electrode 116a and the peripheral adsorption electrode 116b from the adsorption power supply 117 are configured to be independently controllable. The substrate W is adsorbed and held on the substrate support surface 111a by electrostatic force generated by the application of the adsorption voltage from the adsorption power supply 117.

[0032] <Substrate Processing Method Using Plasma Processing Apparatus> Next, an example of a method for processing the substrate W in the plasma processing apparatus 1 configured as above will be described. In the plasma processing apparatus 1, an etching process is performed on the substrate W using, for example, a mask layer on which a pattern has been formed in advance. In this embodiment, the temperature of the electrostatic chuck 114 is raised to a target temperature (e.g., 200°C or higher) before or after the substrate W is placed on the electrostatic chuck 114.

[0033] First, the substrate W is carried into the plasma processing chamber 10 and placed on the electrostatic chuck 114 of the substrate support 11. Next, an AC voltage is applied to the central attracting electrode 116a and the peripheral attracting electrode 116b of the electrostatic chuck 114, and the electrostatic force generated thereby attracts and holds the substrate W on the electrostatic chuck 114. The method of holding the substrate W by the electrostatic chuck 114 will be described in detail later.

[0034] When the substrate W is attracted and held by the electrostatic chuck 114, the interior of the plasma processing chamber 10 is depressurized to a predetermined vacuum level. Next, a processing gas is supplied from the gas supply unit 20 to the plasma processing space 10s via the shower head 13. Furthermore, source RF power for plasma generation is supplied from the first RF generator 31a to the conductive member of the substrate support 11, thereby exciting the processing gas to generate plasma. At this time, bias RF power may be supplied from the second RF generator 31b. Then, in the plasma processing space 10s, the substrate W is subjected to an etching process by the action of the generated plasma.

[0035] When the plasma processing is terminated, the supply of source RF power from the first RF generating unit 31a and the supply of processing gas from the gas supply unit 20 are stopped. If bias RF power has been supplied during the plasma processing, the supply of the bias RF power is also stopped.

[0036] Next, the electrostatic chuck 114 stops attracting and holding the substrate W, and electricity is removed from the plasma-processed substrate W and the electrostatic chuck 114. Thereafter, the substrate W is detached from the electrostatic chuck 114 and carried out of the plasma processing apparatus 1. This completes the series of plasma processing steps.

[0037] <Method of holding a substrate by the substrate support body according to the first embodiment> In this manner, plasma processing is performed on the substrate W in the plasma processing apparatus 1. Next, a method for holding the substrate W by the electrostatic chuck 114 will be described in detail.

[0038] In the substrate support 11 according to this embodiment, the temperatures of the two temperature control regions Z1 and Z2 of the electrostatic chuck 114 are controlled independently as described above. In this case, when the temperature of the electrostatic chuck 114 is increased, the volume resistivity of the electrostatic chuck 114 decreases as described above. Therefore, as shown in FIG. 4A , the amount of charge movement in the high-temperature region of the electrostatic chuck 114 (the peripheral portion of the substrate W in the illustrated example) increases compared to the amount of charge movement in the low-temperature region (the central portion of the substrate W in the illustrated example). As a result, stable adsorption and desorption of the substrate W may become impossible.

[0039] To address this problem, in this embodiment, the amount of charge transfer in the electrostatic chuck 114 is controlled by adjusting the clamping voltages applied to the central clamping electrode 116a and the peripheral clamping electrode 116b in accordance with the temperature of the electrostatic chuck 114. For example, as shown in Fig. 4B , by lowering the clamping voltage applied to the peripheral clamping electrode 116b in the second temperature control zone Z2 where the temperature of the electrostatic chuck 114 is high compared to the clamping voltage applied to the central clamping electrode 116a, the amount of charge transfer is kept substantially constant and the occurrence of residual clamping is suppressed. As described above, the temperature of the electrostatic chuck 114 is controlled by the heater voltage applied from the heater power supply to the central heater electrode 115a and the peripheral heater electrode 115b. Therefore, instead of the temperature of the electrostatic chuck 114, the voltage applied to the central chucking electrode 116a and the peripheral chucking electrode 116b may be adjusted in accordance with the voltage applied to the central heater electrode 115a and the peripheral heater electrode 115b.

[0040] Alternatively, a correlation between the temperature of the electrostatic chuck 114 and the clamping voltages applied to the central clamping electrode 116a and the peripheral clamping electrode 116b may be obtained in advance, and the clamping voltages applied to the central clamping electrode 116a and the peripheral clamping electrode 116b may be controlled based on the correlation. Alternatively, for example, the temperature of the electrostatic chuck 114 may be measured over time during plasma processing, and the clamping voltages applied to the central clamping electrode 116a and the peripheral clamping electrode 116b may be feedback-controlled in accordance with the measured temperature.

[0041] <Effects of the Technology According to the First Embodiment> In the plasma processing apparatus 1 according to the first embodiment, the clamping voltage applied from the clamping power supply 117 to the central clamping electrode 116a and the peripheral clamping electrode 116b is controlled in accordance with the temperature of the electrostatic chuck 114 of the substrate support 11. This controls the amount of charge transfer that would otherwise occur due to an increase in the temperature of the electrostatic chuck 114, and reduces the amount of charge transfer below a threshold at which there is a risk of residual clamping occurring. At this time, by controlling the amount of charge transfer between the substrate W and the central chucking electrode 116a or the peripheral chucking electrode 116b so that it is lower than a threshold at which there is a risk of residual attraction and is uniform (constant) over the entire surface of the electrostatic chuck 114 (substrate W), it is possible to more stably attract and desorb the substrate W. The threshold at which there is a risk of residual attraction may be determined in advance experimentally or by simulation or the like.

[0042] 3, the present embodiment allows for the application of an attracting voltage to each of the central attracting electrode 116a and the peripheral attracting electrode 116b independently. This allows for the application of an attracting voltage according to the temperature of each of the temperature-controlled regions of the electrostatic chuck 114, thereby reducing the risk of residual attraction and enabling more stable attraction and desorption of the substrate W.

[0043] In the above embodiment, the electrostatic chuck 114 is divided into two temperature control regions Z in plan view, but the number of divided temperature control regions Z is not limited to this, and the electrostatic chuck 114 may be divided into three or more temperature control regions. In this case, an attraction electrode may be disposed for each temperature control region Z.

[0044] In the above embodiment, an AC voltage is applied from the chucking power supply 117 to the central chucking electrode 116a and the peripheral chucking electrode 116b. Alternatively, as shown in FIG. 5, a DC voltage may be applied from a DC power supply 32 to the central chucking electrode 116a and the peripheral chucking electrode 116b.

[0045] <Substrate Support According to Second Embodiment> Next, the configuration of the substrate support according to the second embodiment will be described with reference to the drawings. Note that in the substrate support according to the second embodiment, elements having substantially the same functional configuration as those of the substrate support 11 shown in Figures 3A and 3B are designated by the same reference numerals, and descriptions thereof will be simplified or omitted.

[0046] 6A is a vertical cross-sectional view showing the configuration of a substrate support 200 according to the second embodiment. The substrate support 200 includes a main body 211 and a ring assembly 112. The upper surface of the main body 211 has a substrate support surface 211a for supporting the substrate W and a ring support surface 211b for supporting the ring assembly 112. The ring support surface 211b surrounds the substrate support surface 211a in a plan view. The main body 211 includes a base 113 and an electrostatic chuck 214. The electrostatic chuck 214 is disposed on the base 113. The upper surface of the electrostatic chuck 214 has a substrate support surface 211a and a ring support surface 211b. The electrostatic chuck 214 is provided with a central heater electrode 115a and a peripheral heater electrode 115b configured to adjust at least the electrostatic chuck 214 to a target temperature. Inside the electrostatic chuck 114, there are provided a central chucking electrode 216a for chucking and holding the substrate W on the substrate support surface 211a, and a peripheral chucking electrode 216b for chucking and holding the ring assembly 112 on the ring support surface 211b.

[0047] 6A. In one example, the central chucking electrode 216a includes a first central chucking electrode 216a1 and a second central chucking electrode 216a2 that are alternately arranged in the first temperature control zone Z1. The peripheral chucking electrode 216b includes a first peripheral chucking electrode 216b1 and a second peripheral chucking electrode 216b2 that are alternately arranged in the second temperature control zone Z2. That is, the electrostatic chuck 214 in the second embodiment is configured as a Coulomb-type bipolar electrostatic chuck that is capable of independently attracting substrates W for a plurality of temperature control zones Z in a plan view, i.e., for each of the two temperature control zones Z in the example of FIGS. 6A and 6B.

[0048] Adsorption voltages are applied to the first central adsorption electrode 216a1, the second central adsorption electrode 216a2, the first peripheral adsorption electrode 216b1, and the second peripheral adsorption electrode 216b2 from adsorption power sources 217a and 217b for the substrate W, respectively. In one example, the adsorption power sources 217a and 217b are AC power sources. The waveforms of the voltages applied from the adsorption power sources 217a and 217b to the first central adsorption electrode 216a1 and the second central adsorption electrode 216a2 may be sinusoidal or rectangular, or may be other waveforms. The adsorption voltages applied from the adsorption power source 217a to the first central adsorption electrode 216a1 and the second central adsorption electrode 216a2 are configured to be independently controllable. Furthermore, the adsorption voltages applied from the adsorption power source 217b to the first peripheral adsorption electrode 216b1 and the second peripheral adsorption electrode 216b2 are configured to be independently controllable. In the electrostatic chuck 214, the substrate W is attracted and held on the substrate support surface 211a by electrostatic force generated by application of an attracting voltage from an attracting power source 217.

[0049] In the present embodiment, as described above, the first central chucking electrode 216a1, the second central chucking electrode 216a2, the first peripheral chucking electrode 216b1, and the second peripheral chucking electrode 216b2 are connected to the chucking power supplies 217a and 217b, respectively, and chucking voltages are applied to each electrode under independent control. However, the number of chucking power supplies 217 provided in the plasma processing apparatus 1 is not limited to this. For example, the first central chucking electrode 216a1 and the second central chucking electrode 216a2 may be connected to the same chucking power supply 217a, and the first peripheral chucking electrode 216b1 and the second peripheral chucking electrode 216b2 may be connected to the same chucking power supply 217b. Alternatively, for example, the first central chucking electrode 216a1, the second central chucking electrode 216a2, the first peripheral chucking electrode 216b1, and the second peripheral chucking electrode 216b2 may be connected to the same chucking power supply.

[0050] In the substrate support 200 according to this embodiment, the magnitudes of the attraction voltages applied from the attraction power supply 217a to the first central attraction electrode 216a1 and the second central attraction electrode 216a2 each change periodically, and the phase of the attraction voltage applied to the first central attraction electrode 216a1 is different from the phase of the attraction voltage applied to the second central attraction electrode 216a2. Also, the magnitudes of the attraction voltages applied from the attraction power supply 217b to the first peripheral attraction electrode 216b1 and the second peripheral attraction electrode 216b2 each change periodically, and the phase of the attraction voltage applied to the first peripheral attraction electrode 216b1 is different from the phase of the attraction voltage applied to the second peripheral attraction electrode 216b2. The application of the attraction voltages from the attraction power supplies 217a and 217b is controlled by the control unit 2. In the following description, the first central suction electrode 216a1 and the first peripheral suction electrode 216b1 correspond to the "first suction electrodes" according to the technology of the present disclosure, and the second central suction electrode 216a2 and the second peripheral suction electrode 216b2 correspond to the "second suction electrodes" according to the technology of the present disclosure.

[0051] In addition, the following explanation will be given taking as an example a case where an AC voltage is applied from the chucking power supply 217a to the first central chucking electrode 216a1 and the second central chucking electrode 216a2, but the same can be done when an AC voltage is applied from the chucking power supply 217b to the first peripheral chucking electrode 216b1 and the second peripheral chucking electrode 216b2.

[0052] Fig. 6C is a graph showing the relationship between the chucking time (horizontal axis) and the amount of charge transfer (vertical axis) when the electrostatic chuck 214 is controlled to a high temperature. In Fig. 6C, the solid line shows the relationship between the chucking time and the amount of charge transfer when an AC voltage is applied to the first central chucking electrode 216a1 and the second central chucking electrode 216a2 of the electrostatic chuck 214. In Fig. 6C, the dotted line shows the relationship between the chucking time and the amount of charge transfer when a DC voltage is applied to the first central chucking electrode 216a1 and the second central chucking electrode 216a2 of the electrostatic chuck 214.

[0053] As described above, when the electrostatic chuck 214 is controlled to a high temperature, the volume resistivity of the electrostatic chuck 214 decreases. Therefore, when a DC voltage is applied to the first central chucking electrode 216a1 and the second central chucking electrode 216a2 of the electrostatic chuck 214, the amount of charge transfer increases over time, which may result in the electrostatic chuck 214 being unable to attract and hold the substrate W. In contrast, when an AC voltage is applied to the first central chucking electrode 216a1 and the second central chucking electrode 216a2 of the electrostatic chuck 214, the polarity of the attracting voltage changes periodically, and the amount of charge transfer is reset each time. As a result, it is possible to prevent the electrostatic chuck 214 from becoming unstable due to an increase in the amount of charge transfer.

[0054] 7A , when the AC voltage A applied to the first central chucking electrode 216a1 is in phase with the AC voltage B applied to the second central chucking electrode 216a2 (phase difference of 0°), there is a timing when the total voltage applied to the two chucking electrodes becomes 0 V, and at this timing, the substrate W may be detached from the electrostatic chuck 214. Therefore, in the second embodiment, the AC voltage A having a phase different from the phase of the AC voltage B applied to the second central chucking electrode 216a2 is applied to the first central chucking electrode 216a1, thereby suppressing detachment of the substrate W from the electrostatic chuck 214.

[0055] 7B to 7E are graphs showing the relationship between time (horizontal axis) and voltage (vertical axis) when AC voltage A having a phase difference of 30°, 60°, 90°, or 180° with AC voltage B applied to the second central chucking electrode 216a2 is applied to the first central chucking electrode 216a1.

[0056] 7B to 7D, when an AC voltage A having a phase different from that of the AC voltage B applied to the second central chucking electrode 216a2 is applied to the first central chucking electrode 216a1, there is no timing at which the total voltage applied to the substrate W from the two chucking electrodes becomes 0 V. This makes it possible to prevent the substrate W from being detached from the electrostatic chuck 214.

[0057] In particular, as shown in FIG. 7D, when an AC voltage A having a phase difference of 90° with respect to an AC voltage B applied to the second central chucking electrode 216a2 is applied to the first central chucking electrode 216a1, the average value of the total voltage applied to the substrate W becomes the highest and the fluctuation range of the total voltage can be minimized.

[0058] On the other hand, as shown in FIG. 7E, when an AC voltage A having a phase difference of 180° with respect to the AC voltage B applied to the second central chucking electrode 216a2 is applied to the first central chucking electrode 216a1, there is a time when the total voltage applied to the two chucking electrodes becomes 0 V, as in the case shown in FIG. 7A.

[0059] For the above reasons, the phase difference between the AC voltages applied to the first central chucking electrode 216a1 and the second central chucking electrode 216a2 is preferably greater than 0° and less than 180°, and more preferably between 30° and 150°. Furthermore, by setting this phase difference to 90° or close to 90°, for example, between 70° and 110° or between 80° and 100°, the electrostatic chuck 214 can hold the substrate W more stably.

[0060] <Effects of the Technology According to the Second Embodiment> In the substrate support 200 according to the second embodiment, AC voltages of different phases are applied from the chucking power source 217a to the first central chucking electrode 216a1 and the second central chucking electrode 216a2.

[0061] According to the second embodiment, the polarity of the attracting voltage changes periodically, and therefore the amount of charge transfer is reset when the polarity changes. Therefore, even if the electrostatic chuck 214 is controlled to a high temperature (e.g., 200°C or higher) and its volume resistivity decreases, an increase in the amount of charge transfer is suppressed, and it is possible to suppress the attracting and holding of the substrate W from becoming unstable due to the influence of residual charge, etc.

[0062] Furthermore, according to the second embodiment, AC voltages of different phases are applied to the first central chucking electrode 216a1 and the second central chucking electrode 216a2, respectively, so that the total voltage applied to the two chucking electrodes does not become 0 V, and thus it is possible to prevent the substrate W from being detached from the electrostatic chuck 214 during plasma processing.

[0063] Specifically, as described above, by setting the phase difference between the AC voltages applied to the first central chucking electrode 216a1 and the second central chucking electrode 216a2 to be greater than 0° and less than 180°, or between 30° and 150°, it is possible to suppress detachment of the substrate W from the electrostatic chuck 214.

[0064] Furthermore, according to this embodiment, AC voltages having different phases are applied to the first central chucking electrode 216a1 and the second central chucking electrode 216a2, respectively. In addition, the magnitudes of the AC voltages applied from the chucking power supply 217a to the first central chucking electrode 216a1 and the second central chucking electrode 216a2 are controlled in accordance with the temperature of the electrostatic chuck 214, as described in the first embodiment. This enables more stable attraction and desorption of the substrate W when the electrostatic chuck 214 is controlled to a high temperature.

[0065] In the above embodiment, an example has been described in which an AC voltage is applied from the chucking power supply 217a to the first central chucking electrode 216a1 and the second central chucking electrode 216a2. However, as described above, an AC voltage can also be applied from the chucking power supply 217b to the first peripheral chucking electrode 216b1 and the second peripheral chucking electrode 216b2 in a similar manner.

[0066] In addition, in the above embodiment, an example has been described in which an AC voltage is applied from the chucking power supply 217 to the first central chucking electrode 216a1, the second central chucking electrode 216a2, the first peripheral chucking electrode 216b1, and the second peripheral chucking electrode 216b2, but the voltage applied to these chucking electrodes is not limited to an AC voltage.

[0067] For example, the clamping voltage applied to each clamping electrode may be a DC voltage whose magnitude changes periodically. Specifically, as shown in FIG. 8, a switching DC power supply may be used as the clamping power supplies 217a and 217b, so that the magnitude of the voltage applied to each clamping electrode periodically changes between a first voltage value and a second voltage value whose polarity is opposite to that of the first voltage value. In this case, the amount of charge transfer can be reset each time the polarity of the clamping voltage applied to each clamping electrode periodically changes. Therefore, even if the electrostatic chuck 214 is controlled to a high temperature and the volume resistivity is reduced, the substrate W can be stably clamped and de-clamped.

[0068] In this case, the phase of the clamping voltage A applied to the first central clamping electrode 216a1 may be different from the phase of the clamping voltage B applied to the second central clamping electrode 216a2. Furthermore, the phase of the clamping voltage A' applied to the first peripheral clamping electrode 216b1 may be different from the phase of the clamping voltage B' applied to the second peripheral clamping electrode 216b2. This prevents the total voltage applied to the first central clamping electrode 216a1 and the second central clamping electrode 216a2 or the total voltage applied to the first peripheral clamping electrode 216b1 and the second peripheral clamping electrode 216b2 from becoming 0 V, thereby preventing the substrate W from being detached from the electrostatic chuck 214 during plasma processing.

[0069] Although the above embodiment has been described by way of example with respect to a case where the substrate support 200 includes a Coulomb-type bipolar electrostatic chuck 214, the substrate support 200 may include three or more attracting electrodes for each temperature control zone Z of the electrostatic chuck 214. Even in this case, by applying attracting voltages whose magnitudes change periodically to the attracting electrodes, it is possible to stabilize the attraction and desorption of the substrate W to and from the electrostatic chuck 214. Furthermore, by applying attracting voltages of different phases to the attracting electrodes, it is possible to prevent the substrate W from being detached from the electrostatic chuck 214 during plasma processing.

[0070] The embodiments disclosed herein should be considered to be illustrative in all respects and not restrictive, and the above-described embodiments may be omitted, substituted, or modified in various ways without departing from the scope and spirit of the appended claims. [Explanation of symbols]

[0071] 1. Plasma processing equipment 114 Electrostatic Chuck 115a Central heater electrode 115b Peripheral heater electrode 116a Central adsorption electrode 116b Peripheral adsorption electrode 117 Power supply for adsorption W substrate

Claims

1. A substrate support, an electrostatic chuck for attracting a substrate, the electrostatic chuck including a dielectric body and an attracting electrode for attracting the substrate inside the dielectric body; a heater electrode for heating the substrate; an adsorption power supply for applying an adsorption voltage to the adsorption electrode for adsorbing the substrate; a heater power supply for applying a heater voltage to the heater electrode for heating the substrate, a plurality of temperature control regions each including the chucking electrode and the heater electrode; the attraction power supply controls the magnitude of the attraction voltage applied to the attraction electrode based on the magnitude of the heater voltage for each of the plurality of temperature control regions while the substrate is being processed in a state in which the substrate is heated by the heater electrode; and the substrate supporter controls, in the plurality of temperature control regions, the magnitude of the attraction voltage applied to the attraction electrode so that an amount of charge transfer between the substrate and the attraction electrode is lower than a threshold value at which there is a risk of the substrate being residually attracted to the electrostatic chuck.

2. A substrate support, an electrostatic chuck for attracting a substrate, the electrostatic chuck including a dielectric body and an attracting electrode for attracting the substrate inside the dielectric body; a heater electrode for heating the substrate; an adsorption power supply for applying an adsorption voltage to the adsorption electrode for adsorbing the substrate; a heater power supply for applying a heater voltage to the heater electrode for heating the substrate, a plurality of temperature control regions each including the chucking electrode and the heater electrode; the attraction power supply controls, for each of the plurality of temperature control regions, a magnitude of the attraction voltage applied to the attraction electrode based on a magnitude of the heater voltage, and controls, in each of the plurality of temperature control regions, a magnitude of the attraction voltage applied to the attraction electrode so that an amount of charge transfer between the substrate and the attraction electrode is lower than a threshold value at which there is a risk that the substrate will be residually attracted to the electrostatic chuck, and also controls the magnitude of the attraction voltage applied to the attraction electrode so that the amount of charge transfer is constant.

3. the electrostatic chuck is bonded onto a base; 3. The substrate support according to claim 1, wherein the heater electrode is disposed inside the dielectric body and closer to the base than the chucking electrode.

4. the chucking electrodes include a first chucking electrode and a second chucking electrode; 4. The substrate support according to claim 1, wherein the magnitudes of the attraction voltages applied by the attraction power supply to the first attraction electrode and the second attraction electrode respectively change periodically, and the phase of the attraction voltage applied to the first attraction electrode is different from the phase of the attraction voltage applied to the second attraction electrode.

5. The substrate support according to claim 4 , wherein a phase difference between the clamping voltages applied to the first clamping electrode and the second clamping electrode is greater than 0° and less than 180°.

6. 6. The substrate support according to claim 4, wherein a phase difference between the chucking voltages applied to the first chucking electrode and the second chucking electrode is 30 degrees or more and 150 degrees or less.

7. the electrostatic chuck includes a plurality of attraction electrodes; 4. The substrate support according to claim 1, wherein the magnitudes of the attraction voltages applied to the plurality of attraction electrodes by the attraction power supply vary periodically, and the phases of the attraction voltages applied to the plurality of attraction electrodes are different from each other.

8. The substrate support according to claim 7 , wherein the phase difference between any two of the attraction voltages applied to the plurality of attraction electrodes is greater than 0° and less than 180°.

9. The substrate support according to any one of claims 4 to 8, wherein the waveform of the clamping voltage is a sine wave or a square wave.

10. a chamber; A substrate support according to any one of claims 1 to 9, which is arranged in the chamber; A control unit; A substrate processing apparatus comprising:

11. 1. A method of processing a substrate using a substrate processing apparatus including a substrate support, comprising: The substrate support comprises: an electrostatic chuck for attracting a substrate, the electrostatic chuck including a dielectric body and an attracting electrode for attracting the substrate inside the dielectric body; a heater electrode for heating the substrate; an adsorption power supply for applying an adsorption voltage to the adsorption electrode for adsorbing the substrate; a heater power supply for applying a heater voltage to the heater electrode for heating the substrate; Equipped with a plurality of temperature control regions each including the chucking electrode and the heater electrode; The substrate processing method includes: providing the substrate on the electrostatic chuck; applying the heater voltage to the heater electrode to heat the substrate; processing the substrate while the substrate is heated; controlling the magnitude of the attraction voltage applied to the attraction electrode based on the magnitude of the heater voltage during processing of the substrate; Including, In the step of controlling the magnitude of the attraction voltage, the magnitude of the attraction voltage applied to the attraction electrode is controlled based on the magnitude of the heater voltage for each of the plurality of temperature control regions; and the magnitude of the attraction voltage applied to the attraction electrode is controlled in each of the plurality of temperature control regions so that an amount of charge transfer between the substrate and the attraction electrode is lower than a threshold value at which there is a risk of the substrate remaining attracted to the electrostatic chuck.

12. 12. The substrate processing method according to claim 11, wherein the controlling of the magnitude of the attraction voltage comprises controlling the magnitude of the attraction voltage applied to the attraction electrode so that the amount of charge transfer is constant in each of the plurality of temperature control regions.

13. the electrostatic chuck includes a plurality of attraction electrodes; 13. The substrate processing method according to claim 11, wherein the controlling of the magnitude of the attraction voltage comprises periodically changing the magnitude of each of the attraction voltages applied to the plurality of attraction electrodes by the attraction power supply, and applying attraction voltages of different phases to the plurality of attraction electrodes, respectively.

14. 14. The substrate processing method according to claim 13, wherein a phase difference between any two of the attraction voltages applied to the plurality of attraction electrodes is greater than 0° and less than 180°.

15. A substrate processing apparatus, a chamber; a substrate support disposed within the chamber; A control unit; Equipped with The substrate support comprises: an electrostatic chuck for attracting a substrate, the electrostatic chuck including a dielectric body and an attracting electrode for attracting the substrate inside the dielectric body; a heater electrode for heating the substrate; an adsorption power supply for applying an adsorption voltage to the adsorption electrode for adsorbing the substrate; a heater power supply for applying a heater voltage to the heater electrode for heating the substrate; Equipped with a plurality of temperature control regions each including the chucking electrode and the heater electrode; The control unit controls each unit of the substrate processing apparatus, providing the substrate on the electrostatic chuck; applying the heater voltage to the heater electrode to heat the substrate; processing the substrate while the substrate is heated; During the processing of the substrate, a magnitude of the attraction voltage applied to the attraction electrode is controlled for each of the plurality of temperature control regions based on a magnitude of the heater voltage; and controlling, in the plurality of temperature control regions, a magnitude of the attraction voltage applied to the attraction electrode so that an amount of charge transfer between the substrate and the attraction electrode is lower than a threshold value at which there is a risk of the substrate remaining attracted to the electrostatic chuck; configured to perform a process including Substrate processing equipment.

Images