Substrate processing equipment

Abstract

To miniaturize a substrate processing apparatus.SOLUTION: A substrate processing apparatus processing a substrate by using plasma, comprises: a chamber in which the substrate is housed; and a mounting table which is arranged in the chamber, and on which the substrate is mounted. The mounting table includes: a base; a substrate holding part; a plurality of heaters; a heater control part; and an RF filter. The base is formed of a conductor, through which as RF power flows. The substrate holding part is provided on the base, and holds the substrate. The plurality of heaters are provided at the substrate holding part. The heater control part is provided inside the base, and controls a power supplied to each of the plurality of heaters. The RF filter is provided at an outer part of the base, and is connected to wiring for supplying the power to each of the heaters. Further, one RF filter is provided for the plurality of heaters in common.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] Various aspects and embodiments of this disclosure relate to substrate processing equipment Place To relate to. [Background technology]

[0002] A substrate processing apparatus is known that is equipped with multiple heaters and can independently control the temperature of multiple areas of a mounting platform on which a semiconductor wafer (hereinafter referred to as "substrate") is placed (see, for example, Patent Document 1). In a semiconductor manufacturing process using such a substrate processing apparatus, the uniformity of substrate processing can be improved by precisely controlling the temperature of the substrate. [Prior art documents] [Patent Documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2017-228230 [Overview of the project] [Problems that the invention aims to solve]

[0004] This disclosure provides a substrate processing apparatus and a mounting stage that can miniaturize the substrate processing apparatus. [Means for solving the problem]

[0005] One aspect of this disclosure is a substrate processing apparatus that processes a substrate using plasma, comprising a chamber for housing the substrate and a mounting table disposed within the chamber on which the substrate is placed. The mounting table has a base, a substrate holding section, a plurality of heaters, a heater control section, and an RF filter. The base is formed of a conductor and through which RF (Radio Frequency) power flows. The substrate holding section is provided on the base and holds the substrate. The plurality of heaters are provided on the substrate holding section. The heater control section is provided inside the base and controls the power supplied to each of the plurality of heaters. The RF filter is provided outside the base and is connected to the wiring for supplying power to each of the heaters. In addition, one RF filter is provided in common for the plurality of heaters. [Effects of the Invention]

[0006] According to various aspects and embodiments of this disclosure, the substrate processing apparatus can be miniaturized. [Brief explanation of the drawing]

[0007] [Figure 1] Figure 1 is a schematic cross-sectional view showing an example of the configuration of a substrate processing apparatus in the first embodiment of this disclosure. [Figure 2] Figure 2 shows an example of the top surface of an electrostatic chuck. [Figure 3] Figure 3 is an enlarged cross-sectional view showing an example of a detailed structure of the mounting platform. [Figure 4] Figure 4 is a block diagram showing an example of the functional configuration of the control board in the first embodiment. [Figure 5] Figure 5 is a circuit diagram showing an example of a measurement unit. [Figure 6] Figure 6 is a diagram illustrating the temperature difference between the surface temperature of the substrate and the temperature of the resistor. [Figure 7] Figure 7 shows an example of the first correction value table. [Figure 8] Figure 8 shows an example of the second correction value table. [Figure 9]FIG. 9 is a schematic cross-sectional view showing an example of the configuration of a substrate processing apparatus when creating a correction value table. [Figure 10] FIG. 10 is a flowchart showing an example of the processing of a substrate processing apparatus when creating a correction value table. [Figure 11] FIG. 11 is a flowchart showing an example of temperature control in the first embodiment. [Figure 12] FIG. 12 is a block diagram showing an example of the functional configuration of a control board in the second embodiment. [Figure 13] FIG. 13 is a diagram showing an example of a conversion table. [Figure 14] FIG. 14 is a flowchart showing an example of a method for creating a conversion table. [Figure 15] FIG. 15 is a flowchart showing an example of temperature control in the second embodiment.

MODE FOR CARRYING OUT THE INVENTION

[0008] Hereinafter, embodiments of a substrate processing apparatus and a mounting table will be described in detail based on the drawings. Note that the substrate processing apparatus and the mounting table disclosed are not limited by the following embodiments.

[0009] Incidentally, in a substrate processing apparatus in which processing using plasma is performed, since RF power flows through the mounting table, a part of the RF power easily flows into the wiring for supplying power from the outside of the mounting table to the heater inside the mounting table. The wiring for supplying power to the heater is connected to a power supply device via a control device that controls the power supplied to the heater.

[0010] Since the control device and the power supply device are provided outside the substrate processing apparatus, the wiring serves as an antenna, and a part of the RF power flowing through the wiring is radiated outside the substrate processing apparatus, and RF power may flow into the power supply device. In order to suppress this, RF filters are provided for each wiring for supplying power to the heater outside the substrate processing apparatus.

[0011] In recent semiconductor manufacturing processes, further improvements in substrate temperature uniformity are required as miniaturization progresses. To further improve substrate temperature uniformity, it is conceivable to further subdivide the independently temperature-controlled regions on the mounting stage on which the substrate is placed.

[0012] When there are many regions that require independent temperature control, the amount of wiring required to supply power to the heaters in each region increases. An increase in wiring to power the heaters leads to an increase in the number of RF filters. This, in turn, makes the entire substrate processing unit larger.

[0013] Therefore, this disclosure provides a technology that enables miniaturization of substrate processing equipment.

[0014] (First Embodiment) [Configuration of substrate processing apparatus 1] Figure 1 is a schematic cross-sectional view showing an example of the configuration of a substrate processing apparatus 1 in a first embodiment of the present disclosure. The substrate processing apparatus 1 comprises a main apparatus body 10 and a control device 11 that controls the main apparatus body 10. The substrate processing apparatus 1 in this embodiment is, for example, a capacitively coupled plasma etching apparatus.

[0015] The apparatus body 10 has a chamber 12. The chamber 12 provides an internal space 12s within it. The chamber 12 includes a housing 13 formed in a substantially cylindrical shape from, for example, aluminum. The internal space 12s is provided within the housing 13. The housing 13 is electrically grounded. The inner wall surface of the housing 13, i.e., the wall surface defining the internal space 12s, is coated with a plasma-resistant film formed, for example, by anodizing.

[0016] An opening 12p is formed in the side wall of the housing 13 through which the substrate W passes when it is transported between the internal space 12s and the outside of the chamber 12. The opening 12p is opened and closed by a gate valve 12g.

[0017] A mounting platform 16 on which the circuit board W is placed is provided inside the housing 13. The mounting platform 16 is supported by a support portion 15 formed in a substantially cylindrical shape from an insulating material such as quartz. The support portion 15 extends upward from the bottom of the housing 13.

[0018] The mounting base 16 includes a base 19 and an electrostatic chuck 20. The base 19 includes a cover plate 17 and a lower electrode 18. The electrostatic chuck 20 is mounted on the lower electrode 18 of the base 19. The substrate W is placed on the electrostatic chuck 20. The electrostatic chuck 20 has a body made of an insulator and electrodes made of film. A DC power supply is electrically connected to the electrodes of the electrostatic chuck 20. When a voltage is applied from the DC power supply to the electrodes of the electrostatic chuck 20, an electrostatic force is generated on the electrostatic chuck 20, and the substrate W is attracted and held on the upper surface of the electrostatic chuck 20 by this electrostatic force. The electrostatic chuck 20 is an example of a substrate holding part.

[0019] Furthermore, the upper surface of the electrostatic chuck 20 is divided into multiple divided regions 211, as shown in Figure 2, for example. Figure 2 is a diagram showing an example of the upper surface of the electrostatic chuck 20. One heater 200 is embedded inside the electrostatic chuck 20 in each divided region 211. By individually controlling the temperature of the multiple divided regions 211 with each heater 200, the uniformity of the surface temperature of the substrate W can be improved. Note that the heater 200 may be placed between the electrostatic chuck 20 and the lower electrode 18.

[0020] The electrostatic chuck 20 is provided with a pipe 25 for supplying a heat transfer gas, such as He gas, between the electrostatic chuck 20 and the substrate W. By controlling the pressure of the heat transfer gas supplied between the electrostatic chuck 20 and the substrate W, the thermal conductivity between the electrostatic chuck 20 and the substrate W can be controlled.

[0021] The lower electrode 18 is formed in a substantially disc shape from a conductive material such as aluminum. A flow path 18f is formed inside the lower electrode 18 through which a refrigerant, such as Freon, flows. The refrigerant is supplied into the flow path 18f from a chiller unit (not shown) via piping 23a. The refrigerant that has circulated through the flow path 18f is returned to the chiller unit via piping 23b. The refrigerant, whose temperature is controlled by the chiller unit, circulates through the flow path 18f, thereby cooling the lower electrode 18 to a predetermined temperature.

[0022] The cover plate 17 is formed in a roughly disc shape from a conductive material such as aluminum. The cover plate 17 is positioned below the lower electrode 18 and is electrically connected to the lower electrode 18. A recess is formed in the cover plate 17, and a control board 80, which is equipped with elements such as a microcomputer for controlling the multiple heaters 200 in the electrostatic chuck 20, is placed in the recess.

[0023] The control board 80 is supported by the cover plate 17 and the lower electrode 18 via a spacer 170 made of an insulating material. The control board 80 is surrounded by the cover plate 17 and the lower electrode 18, which are made of a conductor.

[0024] One end of a metal wire 73, which supplies power to each heater 200, is connected to the control board 80. The other end of the metal wire 73 is connected to the power supply device 70 via a through hole formed in the bottom of the housing 13 and an RF filter 72. The RF filter 72 is located outside the base 19 and is provided on the metal wire 73 that supplies power to each heater 200. The RF filter 72 is surrounded by a shielding member 71 made of a conductor. The shielding member 71 is electrically connected to the housing 13 and is grounded through the housing 13. Power supplied from the power supply device 70 is supplied to the control board 80 via the RF filter 72 and the metal wire 73.

[0025] Furthermore, one end of an optical fiber cable 75 is connected to the control board 80 for communication between the microcomputer on the control board 80 and the control device 11. The other end of the optical fiber cable 75 is connected to the control device 11. The other end of the optical fiber cable 75 may be connected to another microcomputer located outside the housing 13. In this case, the other microcomputer communicates with the control device 11 via a communication line such as a LAN, thereby relaying communication between the microcomputer on the control board 80 and the control device 11.

[0026] An edge ring 22, formed in an annular shape from a conductive material such as silicon, is provided on the outer periphery of the electrostatic chuck 20. The edge ring 22 is sometimes called a focus ring. The edge ring 22 is positioned to surround the substrate W placed on the electrostatic chuck 20.

[0027] A cover member 28, formed in a substantially cylindrical shape from an insulating material, is provided on the side of the mounting base 16, surrounding the mounting base 16. The cover member 28 protects the side of the mounting base 16 from the plasma generated in the internal space 12s.

[0028] An upper electrode 30 is provided above the mounting base 16. The upper electrode 30 is supported on the upper part of the housing 13 via a member 32 made of an insulating material. The upper electrode 30 has a top plate 34 and a top plate holding part 36. The lower surface of the top plate 34 faces the internal space 12s. The top plate 34 has a plurality of gas discharge holes 34a that penetrate the top plate 34 in the thickness direction. The top plate 34 is made of, for example, silicon. Alternatively, the top plate 34 may be made of, for example, aluminum with a plasma-resistant coating on its surface.

[0029] The top plate holder 36 detachably holds the top plate 34. The top plate holder 36 is made of a conductive material such as aluminum. A gas diffusion chamber 36a is formed inside the top plate holder 36. Multiple gas holes 36b extend downward from the gas diffusion chamber 36a. The gas holes 36b communicate with the gas discharge hole 34a. The top plate holder 36 is provided with a gas inlet 36c connected to the gas diffusion chamber 36a. One end of a pipe 38 is connected to the gas inlet 36c.

[0030] The other end of the piping 38 is connected to a gas source group 40 via a valve group 43, a flow controller group 42, and a valve group 41. The gas source group 40 includes multiple gas sources that supply gases contained in the etching gas. The valve group 41 and the valve group 43 each include multiple valves (e.g., on / off valves). The flow controller group 42 includes multiple flow controllers, such as mass flow controllers.

[0031] Each gas source in the gas source group 40 is connected to the piping 38 via a corresponding valve in the valve group 41, a corresponding flow controller in the flow controller group 42, and a corresponding valve in the valve group 43. Gas from one or more gas sources selected from among the multiple gas sources in the gas source group 40 is supplied into the gas diffusion chamber 36a at individually adjusted flow rates. The gas supplied into the gas diffusion chamber 36a diffuses within the chamber and is then supplied in a shower-like manner into the internal space 12s via the gas holes 36b and gas discharge holes 34a.

[0032] Between the outer wall of the support portion 15 and the inner wall of the housing 13, a baffle plate 48 is provided, which is made of, for example, aluminum with a plasma-resistant coating on its surface. Multiple through holes are formed in the baffle plate 48, penetrating in the thickness direction. An exhaust pipe 52 is connected to the bottom of the housing 13 below the baffle plate 48. An exhaust system 50, which has a pressure controller such as an automatic pressure control valve and a vacuum pump such as a turbomolecular pump, is connected to the exhaust pipe 52. The exhaust system 50 can reduce the pressure in the internal space 12s to a predetermined pressure.

[0033] A first RF power supply 61 is connected to the base 19 via a first matching unit 63. The first RF power supply 61 is a power supply that generates first RF power for plasma generation. The frequency of the first RF power is in the range of 27 to 100 MHz, for example, 60 MHz. The first matching unit 63 has a matching circuit for matching the output impedance of the first RF power supply 61 with the impedance of the load side (for example, the base 19 side). The first RF power supply 61 may also be connected to the upper electrode 30 via the first matching unit 63 instead of the base 19.

[0034] Furthermore, a second RF power supply 62 is connected to the base 19 via a second matching circuit 64. The second RF power supply 62 is a power supply that generates a second RF power for biasing to draw ions into the substrate W. The frequency of the second RF power is lower than the frequency of the first RF power and is in the range of 400 kHz to 13.56 MHz, for example, 400 kHz. The second matching circuit 64 has a matching circuit for matching the output impedance of the second RF power supply 62 with the impedance of the load side (for example, the base 19 side).

[0035] The control device 11 includes memory, a processor, and an input / output interface. The memory stores data such as recipes and programs. The memory can be, for example, RAM (Random Access Memory), ROM (Read Only Memory), HDD (Hard Disk Drive), or SSD (Solid State Drive). The processor controls various parts of the device body 10 via the input / output interface based on the data such as recipes stored in the memory by executing programs read from the memory. The processor can be a CPU (Central Processing Unit) or a DSP (Digital Signal Processor).

[0036] When plasma etching is performed by the substrate processing apparatus 1, the gate valve 12g is opened, and the substrate W is loaded into the housing 13 by a transport robot (not shown) and placed on the electrostatic chuck 20. Then, the gas inside the housing 13 is exhausted by the exhaust device 50, and one or more gases from the gas source group 40 are supplied to the internal space 12s at predetermined flow rates, and the pressure in the internal space 12s is adjusted to a predetermined pressure.

[0037] Furthermore, the lower electrode 18 is cooled by supplying a temperature-controlled refrigerant (not shown) into the flow path 18f. In addition, the power supplied from the power supply device 70 to the heaters 200 provided in each divided region 211 of the electrostatic chuck 20 is controlled by the microcomputer on the control board 80. The control device 11 also controls the pressure of the heat transfer gas supplied between the electrostatic chuck 20 and the substrate W. This adjusts the temperature of the substrate W placed on the electrostatic chuck 20 to a predetermined temperature.

[0038] Then, the first RF power from the first RF power supply 61 and the second RF power from the second RF power supply 62 are supplied to the base 19. As a result, an RF electric field is formed between the upper electrode 30 and the base 19, and the gas supplied to the internal space 12s is turned into plasma. Then, the substrate W is etched by the ions and radicals contained in the plasma generated in the internal space 12s.

[0039] [Details of mounting platform 16] Figure 3 is an enlarged cross-sectional view showing an example of the detailed structure of the mounting base 16. In this embodiment, the electrostatic chuck 20 has a heater 200 and a resistor 201 arranged in each divided region 211. In this embodiment, the resistor 201 is arranged between the heater 200 and the lower electrode 18. The resistance value of the resistor 201 changes with temperature. In this embodiment, the resistor 201 is, for example, a thermistor.

[0040] The heaters 200 and resistors 201 provided in each divided region 211 are connected to the control board 80 via wiring located in through holes formed in the lower electrode 18. The control board 80 is equipped with elements 800, such as a microcomputer, which controls the power supplied to the heaters 200 located in the corresponding divided region 211 based on the temperature measured using the resistors 201 located in each divided region 211.

[0041] Here, since the control board 80 is surrounded by a base 19 made of a conductor, even if RF power is supplied to the base 19, almost no RF power flows to the control board 80. Therefore, even if the control board 80 is not provided with a filter to remove RF power, malfunctions of the element 800 due to RF power will not occur.

[0042] On the other hand, the metal wiring 73 for supplying power to each heater 200 is routed from inside the base 19 to the outside of the base 19 and is not enclosed by the base 19. This allows the RF power supplied to the base 19 to flow easily through the metal wiring 73. For this reason, an RF filter 72 is connected to the metal wiring 73.

[0043] Figure 4 is a block diagram showing an example of the functional configuration of the control board 80 in the first embodiment. The control board 80 is provided with a control unit 81, a plurality of switches 82, and a plurality of measuring units 83 as elements 800. In this embodiment, one switch 82 and one measuring unit 83 are provided for each heater 200 and resistor 201.

[0044] Each switch 82 controls the supply and interruption of power supplied from the power supply device 70 to the corresponding heater 200 via the RF filter 72, in accordance with a control signal from the control unit 81.

[0045] Each measuring unit 83 measures the voltage corresponding to the temperature of the resistor 201 and outputs the measured voltage value to the control unit 81.

[0046] Figure 5 is a circuit diagram showing an example of the measurement unit 83. The measurement unit 83 includes a reference voltage supply unit 830, a reference resistor 831, and an ADC (Analog Digital Converter) 832. The reference voltage supply unit 830 supplies a reference voltage V to the reference resistor 831 and the resistor 201. ref The ADC832 supplies the voltage across the resistor 201, converting the analog signal into a digital signal. The ADC832 then outputs the digitally converted voltage to the control unit 81.

[0047] The control unit 81 receives the set temperature of the base 19 and the set temperature of the substrate W corresponding to each divided region 211 from the control device 11. Then, for each divided region 211, the control unit 81 measures the temperature of the resistor 201 (i.e., the temperature of the divided region 211) based on the voltage value of the resistor 201 provided in the divided region 211. In this embodiment, the resistor 201 is a thermistor. The temperature of the thermistor and the resistance value of the thermistor have a relationship as shown in equation (1) below, for example.

number

[0048] Furthermore, the voltage value output from the ADC832 can be expressed, for example, as shown in equation (2) below.

number

[0049] From equations (1) and (2) above, the temperature Temp of the divided region 211 to be measured can be expressed, for example, as shown in equation (3) below.

number

[0050] In equation (3) above, the voltage value V output from ADC832 ADC All other values ​​are known. Therefore, the voltage value V from the ADC832 ADC By acquiring this data, the control unit 81 can measure the temperature Temp of the divided region 211 where the thermistor resistor 201 is provided.

[0051] The control unit 81 controls the power supplied to the corresponding heater 200 by controlling the corresponding switch 82 for each divided region 211 based on the set temperature of the base 19, the set temperature of the substrate W, and the measured temperature Temp. For example, for each divided region 211, if the measured temperature is lower than the target temperature, the control unit 81 controls the corresponding switch 82 so that power is supplied to the corresponding heater 200 more frequently. On the other hand, if the measured temperature is higher than the target temperature, the control unit 81 controls the corresponding switch 82 so that power is supplied to the corresponding heater 200 less frequently. The control unit 81 is an example of a heater control unit.

[0052] In this embodiment, the RF filter 72 is provided as a single unit common to multiple heaters 200, as shown in Figure 4, for example. If the control board 80 is located outside the base 19, then the number of wires connecting the switch 82 and the heater 200, and the wires connecting the measuring unit 83 and the resistor 201 will be extended to the control board 80 outside the base 19, corresponding to the number of divided regions 211. If the number of divided regions 211 is several tens or more, the number of wires extended to the outside of the base 19 may exceed one hundred.

[0053] Since the wiring that is brought out to the outside of the base 19 passes through the base 19, RF power supplied to the base 19 flows easily through it. Also, since each wire is either for supplying power to the heater 200 individually or for measuring the resistance value of the resistor 201 individually, it is difficult to provide a common filter for removing RF. Therefore, filters for removing RF will be provided individually for each wire.

[0054] When the number of wires leading out of the base 19 exceeds 100, it becomes difficult to secure space for a filter to remove RF. To further improve the in-plane uniformity of temperature control of the substrate W, it is possible to increase the number of divided regions 211. In this case, the number of wires leading out of the base 19 will increase even further, making it even more difficult to secure space for a filter to remove RF.

[0055] In contrast, in this embodiment, the control board 80 is placed inside a base 19 to which RF power is supplied, and is surrounded by the base 19. As a result, almost no RF power flows through the wiring connecting the switch 82 and the heater 200, and the wiring connecting the measurement unit 83 and the resistor 201. Therefore, there is no need to provide filters to remove RF in the wiring connecting the switch 82 and the heater 200, and the wiring connecting the measurement unit 83 and the resistor 201. As a result, the board processing device 1 can be miniaturized.

[0056] [The difference between the surface temperature of substrate W and the measured temperature] Furthermore, in this embodiment, the resistor 201 is positioned between the heater 200 and the lower electrode 18, and the lower electrode 18 is set to a lower temperature than the heater 200. Therefore, the temperature of the substrate W surface and the temperature measured by the resistor 201 have a relationship as shown in Figure 6, for example. Figure 6 is a diagram illustrating the temperature difference Δt between the temperature of the substrate W surface and the temperature of the resistor 201. In Figure 6, the relationship between the distance from the channel 18f and the temperature is illustrated with reference to the upper end of the channel 18f of the lower electrode 18.

[0057] Within the lower electrode 18, the temperature gradually increases as you move away from the flow path 18f. On the other hand, at the contact point between the lower electrode 18 and the electrostatic chuck 20, the thermal conductivity is lower than that inside the lower electrode 18 and the electrostatic chuck 20 due to surface roughness, etc., so the temperature rises rapidly at the contact point between the lower electrode 18 and the electrostatic chuck 20. Also, within the electrostatic chuck 20, the temperature gradually increases as you move away from the flow path 18f up to the position of the heater 200, where the temperature reaches a maximum value.

[0058] And within the electrostatic chuck 20, the temperature gradually decreases as it moves away from the flow path 18f and the electrostatic chuck 20. Further, within the substrate W as well, the temperature gradually decreases as it moves away from the flow path 18f and the electrostatic chuck 20. As a result, there may be a temperature difference Δt between the temperature measured by the resistor 201 and the temperature of the surface of the substrate W.

[0059] Therefore, in this embodiment, the temperature difference Δt between the surface of the substrate W and the resistor 201 is measured, and a correction value based on the measured temperature difference Δt is created. Then, based on the created correction value, the temperature measured by the resistor 201 is corrected.

[0060] For example, consider the case of controlling the temperature of the substrate W to 50 [°C]. The temperature calculated based on the resistance value of the resistor 201 is the temperature of the resistor 201. If the temperature of the resistor 201 is 2 [°C] lower than the temperature of the surface of the substrate W, and the power supplied to the heater 200 is controlled such that the temperature calculated based on the resistance value of the resistor 201 becomes 50 [°C], then the surface of the substrate W will reach 52 [°C].

[0061] Therefore, in this embodiment, the temperature difference obtained by subtracting the temperature of the resistor 201 from the temperature of the surface of the substrate W is calculated as the correction value. In the previous example, the temperature difference is 2 [°C]. And the value obtained by subtracting the correction value C from the set temperature t W of the substrate W is determined as the set temperature t R of the divided region 211 measured by the resistor 201. In the previous example, t R = t W - C.

[0062] The control unit 81 controls the power supplied to the corresponding heater 200 such that the temperature measured by the resistor 201 becomes the determined set temperature t R As a result, in the previous example, the set temperature t RBy controlling the temperature so that it becomes 50-2=48[℃], the surface temperature of the substrate W is controlled to 50[℃].

[0063] Here, the correction value C may vary depending on the temperature of the lower electrode 18 and the temperature difference between the lower electrode 18 and the substrate W. Therefore, in this embodiment, a first correction value C1 is measured for each set temperature of the lower electrode 18, and a second correction value C2 is measured in advance for each temperature difference between the lower electrode 18 and the substrate W. The control unit 81 then determines the correction value C based on the measured first correction value C1 and second correction value C2.

[0064] In this embodiment, the control unit 81 maintains a first correction value table 810, as shown in Figure 7, and a second correction value table 811, as shown in Figure 8, for each divided region 211. The first correction value table 810 stores a first correction value C1, associated with the set temperature of the lower electrode 18, as shown in Figure 7. The second correction value table 811 stores a second correction value C2, associated with the temperature difference between the set temperature of the lower electrode 18 and the set temperature of the surface of the substrate W, as shown in Figure 8. The method for creating the first correction value table 810 and the second correction value table 811, and the method for correcting the temperature measured by the resistor 201 will be described later. In the following, when referring to the first correction value table 810 and the second correction value table 811 collectively without distinction, they will be referred to as the correction value table.

[0065] [Configuration of the substrate processing device 1 when creating the correction value table] When creating the first correction value table 810 and the second correction value table 811, a substrate processing apparatus 1 with a configuration such as that shown in Figure 9 is used. Figure 9 is a schematic cross-sectional view showing an example of the configuration of the substrate processing apparatus 1 when creating the correction value tables. The substrate processing apparatus 1 illustrated in Figure 9 is the same as the substrate processing apparatus 1 illustrated in Figure 1, but with the upper electrode 30 removed and a calibration unit 300 attached. Except for the points described below, in Figure 9, components with the same reference numerals as in Figure 1 have the same or similar functions as the components shown in Figure 1, so their description is omitted.

[0066] When creating the first correction value table 810 and the second correction value table 811, a dummy substrate W' with a black-colored surface is placed on the electrostatic chuck 20, and the temperature distribution of the surface of the dummy substrate W' is measured. The calibration unit 300 has an IR (InfraRed) camera 301 and a cover member 302. The cover member 302 supports the IR camera 301 so that the shooting direction of the IR camera 301 is directed toward the dummy substrate W' on the electrostatic chuck 20. The IR camera 301 measures the surface temperature of the dummy substrate W' based on the amount of infrared radiation emitted from the surface of the dummy substrate W'. The IR camera 301 then outputs the measured surface temperature information of the dummy substrate W' to the control device 11.

[0067] [Process for creating a correction value table] Figure 10 is a flowchart showing an example of the processing performed by the substrate processing apparatus 1 when creating a correction value table. The processing exemplified in Figure 10 is achieved in the substrate processing apparatus 1 exemplified in Figure 9 by the control device 11 controlling each part of the apparatus body 10.

[0068] First, the control device 11 initializes the value of variable k to 1 (S100). Then, the control device 11 sets the temperature of the lower electrode 18 to t k Set to (S101). In step S100, the control device 11 sets the temperature of the refrigerant circulating in the flow path 18f of the lower electrode 18 to t k The chiller unit (not shown) is controlled to achieve this result.

[0069] Next, the control device 11 controls the temperature of each divided region 211 to t k Set to +Δt0 (S102). In this embodiment, Δt0 is, for example, 50 [°C]. In step S101, the control device 11 sets the set temperature t for each divided region 211. k +Δt0 is transmitted to the control unit 81 of the control board 80. The control unit 81 determines that the temperature of each divided region 211, measured based on the voltage value of the resistor 201, is equal to the set temperature t k The power supplied to heater 200 is controlled so that +Δt0 occurs.

[0070] The control device 11 then waits until the temperatures of the lower electrode 18, the electrostatic chuck 20, and the dummy substrate W' stabilize (S103).

[0071] Next, the control device 11 controls the IR camera 301 to measure the surface temperature of the dummy substrate W' (S104).

[0072] Next, the control device 11 calculates the temperature difference Δt between the surface of the dummy substrate W' and the divided region 211 for each divided region 211. Then, the control device 11 applies a correction value C to the calculated temperature difference Δt for each divided region 211. 1k This is saved in the first correction value table 810 (S105).

[0073] Next, the control device 11 increments the value of variable k by 1 (S106) and determines whether the value of variable k is greater than the value of constant m (S107). Constant m is the number of first correction values ​​C1 stored in the first correction value table 810. If the value of variable k is less than or equal to the value of constant m (S107: No), the control device 11 executes the process shown in step S101 again.

[0074] On the other hand, if the value of variable k is greater than the value of constant m (S107: Yes), the control device 11 initializes the value of variable k back to 1 (S108). Then, the control device 11 sets the temperature of the lower electrode 18 to t0 (S109). In this embodiment, t0 is, for example, 10 [°C]. In step S109, the control device 11 controls a chiller unit (not shown) so that the temperature of the refrigerant circulating in the flow path 18f of the lower electrode 18 becomes t0.

[0075] Next, the control device 11 sets the temperature of each divided region 211 to t0 + Δt k Set to (S110). In step S110, the control device 11 sets the set temperature t0 + Δt for each divided region 211. k This is transmitted to the control unit 81 of the control board 80. The control unit 81 determines that the temperature of each divided region 211, measured based on the voltage value of the resistor 201, is set to the set temperature t0 + Δt. k The power supplied to the heater 200 is controlled to achieve this.

[0076] The control device 11 then waits until the temperatures of the lower electrode 18, the electrostatic chuck 20, and the dummy substrate W' stabilize (S111).

[0077] Next, the control device 11 controls the IR camera 301 to measure the surface temperature of the dummy substrate W' (S112).

[0078] Next, the control device 11 calculates the temperature difference Δt between the surface of the dummy substrate W' and the divided region 211 for each divided region 211. Then, the control device 11 applies a correction value C to the calculated temperature difference Δt for each divided region 211. 2k This is saved in the second correction value table 811 (S113).

[0079] Next, the control device 11 increments the value of variable k by 1 (S114) and determines whether the value of variable k is greater than the value of the constant n (S115). The constant n is the number of second correction values ​​C2 stored in the second correction value table 811. If the value of variable k is less than or equal to the value of the constant n (S115: No), the control device 11 executes the process shown in step S110 again. On the other hand, if the value of variable k is greater than the value of the constant n (S115: Yes), the control device 11 terminates the process shown in this flowchart.

[0080] [Temperature control during processing of substrate W] Figure 11 is a flowchart illustrating an example of temperature control in the first embodiment. The process illustrated in Figure 11 is realized by the control unit 81 controlling each part of the control board 80 in the substrate processing apparatus 1 illustrated in Figure 1. The control unit 81 holds the first correction value table 810 and the second correction value table 811 created by the process illustrated in Figure 10 before the process illustrated in Figure 11 is started.

[0081] First, the control unit 81 obtains the set temperature of the substrate W to be processed from the control device 11 (S200). The control unit 81 also obtains the set temperature of the lower electrode 18 from the control device 11 (S201). Then, the control unit 81 refers to the first correction value table 810 and identifies a first correction value C1 for each divided region 211 that corresponds to the set temperature of the lower electrode 18 obtained in step S201 (S202). Then, the control unit 81 refers to the second correction value table 811 and identifies a second correction value C2 for each divided region 211 that corresponds to the temperature difference Δt between the set temperature of the substrate W and the set temperature of the lower electrode 18 (S203).

[0082] Next, the control unit 81 determines the set temperature of each divided region 211 based on the identified first correction value C1 and second correction value C2 (S204). In step S204, the control unit 81 determines the set temperature of each divided region 211 based on, for example, equation (4) below R To decide.

number

[0083] Next, the control unit 81 determines the set temperature t in step S204. R Based on this, the power supplied to the heater 200 of each divided region 211 is controlled (S205).

[0084] Next, the control unit 81 determines whether or not it has been notified by the control device 11 that the process has ended (S206). If it is notified that the process has ended (S206: Yes), the process shown in this flowchart ends.

[0085] On the other hand, if the completion of processing has not been notified (S206: No), the control unit 81 determines whether or not the control device 11 has instructed a change in the set temperature of the substrate W (S207). If a change in the set temperature of the substrate W has not been instructed (S207: No), the control unit 81 executes the process shown in step S205 again. On the other hand, if a change in the set temperature of the substrate W has been instructed (S207: Yes), the control unit 81 executes the process shown in step S200 again.

[0086] The first embodiment has been described above. As described above, the substrate processing apparatus 1 in this embodiment is a substrate processing apparatus 1 that processes a substrate W using plasma, and comprises a chamber 12 in which the substrate W is housed, and a mounting table 16 arranged inside the chamber 12 on which the substrate W is placed. The mounting table 16 has a base 19, an electrostatic chuck 20, a plurality of heaters 200, a control unit 81, and an RF filter 72. The base 19 is made of a conductor and through which RF power flows. The electrostatic chuck 20 is provided on the base 19 and holds the substrate W. The plurality of heaters 200 are provided on the electrostatic chuck 20. The control unit 81 is provided inside the base 19 and controls the power supplied to each of the plurality of heaters 200. The RF filter 72 is provided outside the base 19 and is connected to metal wiring 73 for supplying power to each of the electrostatic chucks 20. In addition, one RF filter 72 is provided in common for the plurality of heaters 200. This makes it possible to miniaturize the substrate processing device 1.

[0087] Furthermore, in the above-described embodiment, the mounting table 16 has a plurality of resistors 201 arranged near each heater 200, the resistors 201 whose resistance value changes with temperature, and a plurality of measuring units 83 that measure the resistance value of each resistor 201. The control unit 81 controls the supply of power to the corresponding heater 200 based on the temperature corresponding to the resistance value measured by the switch 82. This makes it possible to accurately control the temperature of the region of the substrate W corresponding to the region where each heater 200 is provided.

[0088] Furthermore, in the above-described embodiment, each resistor 201 is positioned between the corresponding heater 200 and the base 19. This allows the heat from the heater 200 to be efficiently transferred to the substrate W.

[0089] Furthermore, in the above-described embodiment, the control unit 81 corrects the temperature corresponding to the resistance value of each resistor 201 based on the temperature difference between the temperature corresponding to the resistance value of the resistor 201 and the temperature at the location on the substrate W corresponding to the location where the resistor 201 is installed, and controls the supply of power to the corresponding heater 200 based on the corrected temperature. This makes it possible to control the temperature of the substrate W with greater precision.

[0090] Furthermore, in the embodiment described above, the resistor 201 is a thermistor. This allows for precise control of the temperature of the substrate W.

[0091] Furthermore, the above-described embodiment is a mounting table 16 on which a substrate W is placed, which is arranged in a chamber 12 of a substrate processing apparatus 1 that processes substrates using plasma, and comprises a base 19, an electrostatic chuck 20, a plurality of heaters 200, a control unit 81, and an RF filter 72. The base 19 is made of a conductor and through which RF power flows. The electrostatic chuck 20 is provided on the base 19 and holds the substrate W. The plurality of heaters 200 are provided on the electrostatic chuck 20. The control unit 81 is provided inside the base 19 and controls the power supplied to each of the plurality of heaters 200. The RF filter 72 is provided outside the base 19 and is connected to metal wiring 73 for supplying power to each of the heaters 200. In addition, one RF filter 72 is provided in common for the plurality of heaters 200. This makes it possible to miniaturize the mounting table 16.

[0092] (Second embodiment) In the first embodiment, the temperature of the divided region 211 where the resistor 201 was provided was measured based on the resistance value of the resistor 201, which was provided separately from the heater 200. In contrast, in this embodiment, the temperature of the divided region 211 where the heater 200 was provided is measured based on the resistance value of the heater 200. As a result, the resistor 201 is unnecessary, and the mounting base 16 can be made smaller.

[0093] The following section will focus on explaining the differences from the first embodiment. Note that the configuration of the substrate processing apparatus 1 is the same as that of the substrate processing apparatus 1 in the first embodiment described with reference to Figures 1 to 3, so its explanation will be omitted.

[0094] [Functional blocks of the control board 80] Figure 12 is a block diagram showing an example of the functional configuration of the control board 80 in the second embodiment. The control board 80 is equipped with elements 800 including a control unit 85, a voltmeter 86, multiple ammeters 87, multiple switches 88, and multiple measuring units 89. One ammeter 87, one switch 88, and one measuring unit 89 are provided for each heater 200.

[0095] Each switch 88 controls the supply and interruption of power supplied to the corresponding heater 200 via the RF filter 72, in accordance with a control signal from the control unit 85.

[0096] The voltmeter 86 measures the voltage supplied to each heater 200 and outputs the measured voltage to the respective measuring unit 89.

[0097] Each ammeter 87 measures the current flowing through the heater 200 when power is supplied to the heater 200 by the switch 88, and outputs the measured current to the corresponding measuring unit 89.

[0098] Each measuring unit 89 uses the voltage measurement output from the voltmeter 86 and the current measurement output from the corresponding ammeter 87 to calculate the resistance value of the corresponding heater 200. Then, each measuring unit 89 outputs the calculated resistance value to the control unit 85.

[0099] The control unit 85 holds a conversion table 850, for example, as shown in Figure 13. Figure 13 is a diagram showing an example of the conversion table 850. The conversion table 850 stores an individual table 852 for each identifier 851 that identifies each divided region 211. Each individual table 852 stores the resistance value of the heater 200 placed in the divided region 211, corresponding to the temperature of the divided region 211 identified by the identifier 851.

[0100] The control unit 85 acquires the resistance values ​​measured by the measurement unit 89 for each heater 200 provided in each divided region 211. The control unit 85 then extracts an individual table 852 corresponding to the acquired resistance value from the conversion table 850, and refers to the extracted individual table 852 to determine the temperature corresponding to the acquired resistance value. If the same resistance value as the acquired resistance value is not stored in the individual table 852, the control unit 85 determines the temperature corresponding to the acquired resistance value by linearly interpolating a resistance value close to the acquired resistance value.

[0101] The control unit 85 then corrects the identified temperature for each divided region 211 in the same manner as in the first embodiment. The control unit 85 then controls the power supply to the corresponding heater 200 by controlling the corresponding switch 88 so that the corrected temperature for each divided region 211 becomes the set temperature of the substrate W notified by the control device 11.

[0102] [Creating conversion table 850] Figure 14 is a flowchart showing an example of how to create a conversion table 850. The process illustrated in Figure 14 is realized in the substrate processing apparatus 1 illustrated in Figure 9 by the control device 11 controlling each part of the apparatus body 10.

[0103] First, the control device 11 selects one unselected temperature from among the multiple temperatures stored in the conversion table 850 (S300).

[0104] Next, the control device 11 controls the IR camera 301 to start measuring the surface temperature of the dummy substrate W' (S301).

[0105] Next, the control device 11 adjusts the power supplied to the heater 200 of each divided region 211 so that the difference between the temperature selected in step S300 and the surface temperature of the dummy substrate W' is less than or equal to a predetermined temperature (for example, less than 0.1 [°C]) (S302). In step S302, based on the surface temperature of the dummy substrate W' measured by the IR camera 301, the control device 11 instructs the control unit 85 to increase or decrease the power supplied to the heater 200 of each divided region 211. The control unit 85 controls the switch 88 corresponding to each divided region 211 in response to the instruction from the control device 11.

[0106] If the difference between the temperature selected in step S300 and the surface temperature of the dummy substrate W' falls below a predetermined temperature, the control device 11 obtains the resistance value of the heater 200 of each divided region 211 from the control unit 85 (S303).

[0107] Next, the control device 11 determines whether all temperatures stored in the conversion table 850 have been selected (S304). If there are any unselected temperatures (S304: No), the process shown in step S300 is executed again.

[0108] On the other hand, if all temperatures are selected (S304: Yes), the control device 11 creates a conversion table 850 by storing the resistance values ​​of the heaters 200 in an individual table 852, corresponding to the selected temperature for each divided region 211 (S305). Then, the control device 11 has the control unit 85 save the created conversion table (S306). The process shown in this flowchart then ends.

[0109] [Temperature control during processing of substrate W] Figure 15 is a flowchart showing an example of temperature control in the second embodiment. The process illustrated in Figure 15 is realized in the substrate processing apparatus 1 illustrated in Figure 1 by the control unit 85 controlling each part of the control board 80. The control unit 85 holds the conversion table 850 created by the process illustrated in Figure 14 before the process illustrated in Figure 15 is started.

[0110] First, the control unit 85 obtains the set temperature of the substrate W to be processed from the control device 11 (S400). Then, the control unit 85 obtains the resistance value of the heater 200 for each divided region 211 from the measurement unit 89 (S401).

[0111] Next, the control unit 85 refers to the conversion table 850 and identifies the temperature of the region of the substrate W corresponding to each divided region 211 (S402). Then, for each divided region 211, the control unit 85 controls the power supplied to the heater 200 based on the difference between the temperature identified in step S402 and the set temperature of the substrate W obtained in step S400 (S403). For example, for each divided region 211, the control unit 85 controls the power supplied to the heater 200 so that the difference between the temperature identified in step S402 and the set temperature of the substrate W obtained in step S400 is less than or equal to a predetermined temperature (for example, a temperature of less than 0.1 [°C]).

[0112] Next, the control unit 85 determines whether or not it has been notified by the control device 11 that the process has ended (S404). If it is notified that the process has ended (S404: Yes), the process shown in this flowchart ends.

[0113] On the other hand, if the completion of processing has not been notified (S404: No), the control unit 85 determines whether or not the control device 11 has instructed a change in the set temperature of the substrate W (S405). If a change in the set temperature of the substrate W has not been instructed (S405: No), the control unit 85 executes the process shown in step S401 again. On the other hand, if a change in the set temperature of the substrate W has been instructed (S405: Yes), the control unit 85 executes the process shown in step S400 again.

[0114] The second embodiment has been described above. In this embodiment as well, the substrate processing apparatus 1 can be miniaturized.

[0115] [others] Furthermore, the technology disclosed in this application is not limited to the embodiments described above, and numerous modifications are possible within the scope of its essence.

[0116] For example, in the embodiment described above, the substrate processing apparatus 1 was described as an apparatus that uses plasma to etch a substrate W, but the disclosed technology is not limited to this. For example, the disclosed technology can also be applied to apparatus that uses plasma to perform processes such as film formation and modification.

[0117] Furthermore, in the above-described embodiment, a substrate processing apparatus 1 that uses capacitively coupled plasma (CCP) as an example of a plasma source was explained, but the plasma source is not limited to this. Examples of plasma sources other than capacitively coupled plasma include inductively coupled plasma (ICP), microwave-excited surface wave plasma (SWP), electron cycloton resonance plasma (ECP), and helicon wave-excited plasma (HWP).

[0118] It should be noted that the embodiments disclosed herein are illustrative and not restrictive in all respects. Indeed, the embodiments described above can be embodied in a variety of forms. Furthermore, the embodiments described above may be omitted, replaced, or modified in various ways without departing from the scope and spirit of the appended claims. [Explanation of symbols]

[0119] W board W' Dummy board 1. Substrate processing device 10 Main unit of the device 11 Control device 12 Chambers 13 cabinets 16 Mounting platform 17 Cover Plate 18 Lower electrode 19 Base 20 Electrostatic Chuck 200 Heater 201 Resistor 211 Split area 30 Upper electrode 300 Calibration Units 301 IR Camera 34 Top plate 36 Top plate holding part 50 Exhaust system 61 First RF Power Supply 62 Second RF power supply 63 First Matching Unit 64 Second Matching Unit 70 Power supply equipment 71 Shielding member 72 RF filters 73 Metal wiring 75 Fiber optic cable 80 Control board 800 elements 81 Control Unit 810 First Correction Value Table 811 Second Correction Value Table 82 switches 83 Measuring part 830 Reference voltage supply unit 831 Reference resistor 832 ADC 85 Control Unit 850 Conversion Table 851 Identifier 852 Individual Tables 86 Voltmeter 87 Ammeter 88 Switch 89 Measuring section

Claims

1. A substrate processing chamber and A control device provided outside the substrate processing chamber, A base placed inside the substrate processing chamber, An electrostatic chuck is positioned on top of the base and includes multiple divided regions that are divided radially and circumferentially, A control board is placed in the space defined within the base, A fiber optic cable connecting the control device and the control board. Equipped with, The electrostatic chuck is, A heater is placed inside each of the aforementioned plurality of divided regions, A resistor is placed inside each of the plurality of divided regions, the resistor whose resistance value changes depending on the temperature inside the divided region. Includes, The control board is A switch electrically connected to the heater, A measuring unit for measuring the voltage value across the resistor, A control unit controls the power supplied to the heater by controlling the switch based on the voltage value measured by the measuring unit and the set temperature received from the control device via the optical fiber cable. A substrate processing apparatus, including

2. The control board is The substrate processing apparatus according to claim 1, wherein it is electrically connected to a power supply device via an RF filter provided outside the substrate processing chamber.

3. The front RF filter is The substrate processing apparatus according to claim 2, which is provided in common to the heaters arranged inside each of the plurality of divided regions.

4. The RF filter is The substrate processing apparatus according to claim 2 or 3, wherein the substrate processing chamber is surrounded by a shielding member that is electrically connected to a grounded housing of the substrate processing chamber.

5. The aforementioned measuring unit is A reference resistor connected in series with the aforementioned resistor, A reference voltage supply unit electrically connected to the aforementioned reference resistor, An ADC (Analog Digital Converter) is electrically connected between the resistor and the reference resistor. A substrate processing apparatus according to any one of claims 1 to 4, including the following:

6. The control unit, A first correction value determined by the set temperature of the base is maintained. A substrate processing apparatus according to any one of claims 1 to 5, wherein the power supplied to the heater is controlled by controlling the switch based on the first correction value determined by the set temperature of the base received from the control device via the optical fiber cable.

7. The control unit, The substrate processing apparatus according to claim 6, wherein the first correction value is maintained for each of the divided regions.

8. The control unit, A substrate processing apparatus according to any one of claims 1 to 7, wherein it maintains a second correction value determined by the temperature difference between the set temperature of the base and the set temperature of the substrate surface, and controls the power supplied to the heater by controlling the switch based on the second correction value identified by the temperature difference between the set temperature of the base and the set temperature of the substrate surface received from the control device via the optical fiber cable.

9. The control unit, The substrate processing apparatus according to claim 8, wherein the second correction value is maintained for each of the divided regions.

10. The aforementioned switch is A substrate processing apparatus according to any one of claims 1 to 9, provided one for each of the heaters.

11. The aforementioned measuring unit is A substrate processing apparatus according to any one of claims 1 to 10, provided one for each resistor.

12. The substrate processing apparatus according to any one of claims 1 to 11, wherein the resistor is disposed below the heater.

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