Temperature control device, temperature control method, and mounting table

Abstract

A temperature control device, a temperature control method, and a stage are provided. The accuracy of temperature control of a processed substrate is maintained at high accuracy even in the case where a wire breakage occurs in a heater. A substrate processing device includes an electrostatic chuck, a control section, and a plurality of heaters. Each of the divided regions inside the electrostatic chuck has a plurality of heaters embedded therein. The plurality of heaters embedded in each of the divided regions are connected in parallel. The control section determines, for each of the divided regions, whether a part of the heaters embedded in each of the divided regions has a wire breakage based on a total value of currents flowing through the plurality of heaters embedded in the divided region. Then, the control section controls so that the current flowing through each of the heaters in the divided region in which a part of the heaters embedded therein has a wire breakage is more than the current flowing through each of the heaters in the divided region in which none of the plurality of heaters has a wire breakage in the case where it is determined that a part of the heaters embedded in the divided region has a wire breakage.

Description

[0001] This application is a divisional application of an application filed on October 10, 2017, with application number 201710935336.0 and invention name “Temperature Control Device, Temperature Control Method, and Mounting Table”. Technical Field

[0002] Aspects and embodiments of the present invention relate to a temperature control device, a temperature control method, and a mounting table. Background Art

[0003] In semiconductor manufacturing processes, the temperature of the semiconductor wafer, the substrate being processed, is one of the most important factors affecting the semiconductor's properties. Therefore, high-precision temperature control of the semiconductor wafer is required throughout the manufacturing process. To achieve this, one approach is to divide the stage used to hold the semiconductor wafer into multiple zones, and then install independently controllable heaters in each zone.

[0004] Furthermore, during the manufacturing process, variations in temperature distribution may occur locally on the semiconductor wafer due to factors such as the temperature and pressure of the process gas, the distribution of high-frequency power, and the flow of the process gas. To mitigate this, it is possible to divide the mounting table into smaller areas and independently control the temperature of each area using heaters embedded in each area.

[0005] As the number of sections of the mounting platform increases, the area of ​​each section decreases, and the size of the heaters embedded in each section also decreases. As the size of the heater decreases, the heater becomes thinner to generate the required amount of heat. This increases the risk of heater disconnection. The mounting platform is sometimes divided into hundreds of sections. If a heater disconnects in a single section, the entire mounting platform must be replaced, increasing semiconductor manufacturing costs.

[0006] To avoid this situation, an automatic correction method is known in which, when a portion of a heater is broken, the heat of the surrounding heaters is controlled so that the heaters surrounding the broken heater compensate for the heat that should be generated by the broken heater (for example, refer to the following patent document 1).

[0007] Patent Document 1: Japanese Patent Application Laid-Open No. 2016-6875 Summary of the Invention

[0008] Problems to be solved by the invention

[0009] Furthermore, in conventional automatic correction methods, if a broken heater is adjacent to a healthy heater, the surrounding heaters can compensate for the heat that would have been generated by the broken heater. However, if multiple adjacent heaters are broken, the broken heater may not be adjacent to the healthy heaters. In such cases, compensating for the heat that would have been generated by the broken heater using the surrounding heaters is difficult.

[0010] Solutions for solving problems

[0011] One aspect of the present invention is a temperature control device comprising a loading platform, a control unit, and a plurality of heaters. The loading platform is used to load a substrate to be processed. A plurality of heaters are respectively embedded in each divided area inside the loading platform, and each divided area is obtained by dividing the upper surface of the loading platform into a plurality of areas. The control unit determines, for each divided area, whether a portion of the heater embedded in each divided area is broken based on the total value of the current flowing through the plurality of heaters embedded in the divided area. In addition, the plurality of heaters embedded in each divided area are connected in parallel. In addition, for each divided area, when it is determined that a portion of the heater embedded in the divided area is broken, the control unit controls so that the current flowing through each heater in the divided area where the portion of the heater embedded in the divided area is broken is greater than the current flowing through each heater when all heaters are intact.

[0012] Effects of the Invention

[0013] According to aspects and embodiments of the present invention, even when a heater is disconnected, the temperature of a substrate to be processed can be controlled with high accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a cross-sectional view showing an example of a substrate processing apparatus.

[0015] Figure 2 This is a diagram showing an example of the upper surface of an electrostatic chuck.

[0016] Figure 3 This is a diagram showing an example of the structure of the heater provided in each divided area.

[0017] Figure 4 This is a block diagram showing an example of a control panel.

[0018] Figure 5 This is a flowchart showing an example of temperature control processing.

[0019] Figure 6This is a diagram showing another example of the structure of the heater provided in each divided area.

[0020] Description of Reference Numerals

[0021] G: gate valve; V: valve; W: semiconductor wafer; 100: substrate processing device; 1: chamber; 2a: substrate; 2b: flow path; 2c: piping; 2d: piping; 3: insulating plate; 3a: inner wall member; 4: support table; 5: focusing ring; 6: electrostatic chuck; 6a: electrode; 6b: insulating layer; 6c: heater; 6d: dividing area; 9: annular magnet; 11a, 11b: matching device; 12a, 12b: high-frequency power supply; 13: DC power supply; 15: processing gas supply source; 15a: MFC; 15b: piping; 16: nozzle; 16a: main body; 16b: upper top plate; 16c: gas diffusion chamber; 16e: gas outlet ;16f: Gas inlet port;16g: Gas inlet port;20: Control panel;200: Wiring;21: Control unit;22: Control block;23: Voltage control unit;24: Switch;25: Current control unit;26: Amperemeter;31: Heat transfer gas supply unit;32: Piping;33: Cooling unit;40: LPF;41: Switch;42: Variable DC power supply;45: Insulating component;60: Control device;61: Processing controller;62: User interface;63: Storage unit;71: Exhaust port;72: Exhaust pipe;73: Exhaust device;74: Opening;76: Sediment shielding member;77: Sediment shielding member;79: Conductive component. DETAILED DESCRIPTION

[0022] In one embodiment, the disclosed temperature control device includes a loading platform, a control unit, and a plurality of heaters. The loading platform is used to load a substrate to be processed. A plurality of heaters are respectively embedded in each divided area inside the loading platform, and each divided area is obtained by dividing the upper surface of the loading platform into a plurality of areas. The control unit determines whether a part of the heater embedded in each divided area is broken based on the total value of the current flowing through the plurality of heaters embedded in the divided area. In addition, the plurality of heaters embedded in each divided area are connected in parallel. In addition, the control unit controls each divided area when it is determined that a part of the heater embedded in the divided area is broken, so that the current flowing through each heater in the divided area where the part of the heater embedded in the divided area is broken is greater than the current flowing through each heater when all heaters are not broken.

[0023] Furthermore, in one embodiment of the disclosed temperature control device, two heaters connected in parallel may be embedded in each divided area. Furthermore, the control unit may determine, for each divided area, that a portion of the heaters embedded in the divided area has a disconnection if the total current flowing through the two heaters embedded in the divided area is less than a first threshold value and equal to or greater than a second threshold value that is smaller than the first threshold value, wherein the first threshold value is less than the total current flowing through the two heaters embedded in the divided area if none of the heaters have a disconnection.

[0024] In one embodiment of the disclosed temperature control device, the heater may be a resistance heater. Furthermore, the first threshold value may be a value obtained by adding a predetermined margin to half the total value of the current flowing through the two heaters embedded in the divided region when all heaters are intact, or the second threshold value may be a value obtained by adding a predetermined margin to zero.

[0025] In one embodiment of the disclosed temperature control device, the control unit may control each divided area when it is determined that a portion of the heaters embedded in the divided area is broken, so that the current flowing through each heater in the divided area where the portion of the heaters embedded in the divided area is broken becomes the current flowing through each heater when all the heaters are not broken. times.

[0026] In one embodiment of the disclosed temperature control device, the mounting table may include a plurality of stacked insulating layers, and each of the plurality of heaters embedded in the divided region may be arranged on a different surface of one of the plurality of insulating layers.

[0027] In one embodiment of the disclosed temperature control device, the mounting table may include a plurality of stacked insulating layers, and the plurality of heaters embedded in the divided regions may be arranged on the same surface of one of the plurality of insulating layers.

[0028] In addition, in one embodiment, the disclosed temperature control method is used to control the temperature of a processed substrate placed on a carrier, and the temperature control method includes the following steps: for each divided area inside the carrier, measuring the total value of the current flowing through a plurality of heaters respectively embedded and connected in parallel for each divided area, each divided area being obtained by dividing the upper surface of the carrier into a plurality of areas; based on the total value of the current in each divided area, determining for each divided area whether a part of the embedded heater is broken; and for each divided area, controlling when it is determined that a part of the heater embedded in the divided area is broken, so that the current flowing through each heater in the divided area where the part of the heater embedded in the divided area is broken is greater than the current flowing through each heater when all heaters are not broken.

[0029] In addition, in one embodiment, the disclosed loading platform is used to carry a processed substrate, and the loading platform is equipped with multiple heaters, which are respectively embedded in each divided area inside the loading platform. Each divided area is obtained by dividing the upper surface of the loading platform into multiple areas, and the multiple heaters embedded in each divided area are connected in parallel.

[0030] Hereinafter, embodiments of the disclosed temperature control device, temperature control method, and mounting table will be described in detail based on the accompanying drawings.

[0031] [Example]

[0032] [Structure of Substrate Processing Apparatus 100]

[0033] Figure 1 1 is a cross-sectional view showing an example of the structure of the substrate processing apparatus 100. Figure 1 As shown, substrate processing apparatus 100 includes an airtight, electrically grounded chamber 1. Chamber 1 is formed into a generally cylindrical shape, for example, from aluminum with an anodized surface coating. In this embodiment, substrate processing apparatus 100 is a capacitively coupled parallel plate plasma processing apparatus.

[0034] A substrate 2a, made of a conductive metal such as aluminum, is placed within chamber 1. Substrate 2a functions as a lower electrode. Substrate 2a is supported by a conductive support 4 mounted on an insulating plate 3. Furthermore, a focusing ring 5, made of, for example, single-crystal silicon, is placed above and around substrate 2a. Furthermore, a cylindrical inner wall member 3a, made of, for example, quartz, is placed around substrate 2a and support 4 to surround them.

[0035] A showerhead 16 is positioned above the substrate 2a, facing the substrate 2a in a manner substantially parallel to the substrate 2a, in other words, facing the semiconductor wafer W disposed on the substrate 2a. This showerhead 16 functions as an upper electrode. The showerhead 16 and the substrate 2a function as a pair of electrodes (upper and lower electrodes). The substrate 2a is connected to a high-frequency power supply 12a via a matching box 11a. Furthermore, the substrate 2a is connected to a high-frequency power supply 12b via a matching box 11b.

[0036] The high-frequency power source 12a supplies high-frequency power of a predetermined frequency (e.g., 100 MHz) to the substrate 2a, for example, for generating plasma. Furthermore, the high-frequency power source 12b supplies high-frequency power of a predetermined frequency (e.g., 13 MHz) to the substrate 2a, for example, for attracting ions (bias). The high-frequency power source 12b supplies high-frequency power of a predetermined frequency (e.g., 13 MHz) lower than the frequency of the high-frequency power source 12a, for example, for attracting ions (bias). The control device 60, described later, controls the on / off switching of the high-frequency power sources 12a and 12b and the high-frequency power supplied by the high-frequency power sources 12a and 12b.

[0037] An electrostatic chuck 6 is provided on the upper surface of the substrate 2a. This electrostatic chuck 6 is used to attract and hold a semiconductor wafer W, an example of a substrate to be processed, and to control the temperature of the semiconductor wafer W. The electrostatic chuck 6 includes a plurality of stacked insulating layers 6b, an electrode 6a disposed between the insulating layers 6b, and a plurality of heaters 6c. The electrode 6a is connected to a DC power supply 13. The heater 6c is connected to a control board 20, described later. The electrode 6a generates a Coulomb force on the surface of the electrostatic chuck 6 using the DC voltage applied from the DC power supply 13, thereby attracting and holding the semiconductor wafer W to the upper surface of the electrostatic chuck 6 using this Coulomb force. The DC power supply 13 is turned on and off by a control device 60, described later.

[0038] Furthermore, the electrostatic chuck 6 heats the semiconductor wafer W using heat generated by the heater 6 c. The top surface of the electrostatic chuck 6 is divided into a plurality of regions, or divided areas, with a plurality of heaters 6 c embedded in each divided area. In this embodiment, two heaters 6 c are embedded in each divided area. In this embodiment, the electrostatic chuck 6 is an example of a mounting table.

[0039] A flow path 2b, through which a refrigerant such as a heat transfer fluid (Japanese: ガルデン) flows, is formed within the substrate 2a. This flow path 2b is connected to the cooling unit 33 via pipes 2c and 2d. The refrigerant supplied from the cooling unit 33 circulates within the flow path 2b, thereby cooling the substrate 2a through heat exchange with the refrigerant. The temperature and flow rate of the refrigerant supplied from the cooling unit 33 are controlled by a control device 60, described later.

[0040] Furthermore, a pipe 32 is provided in the substrate 2 a so as to penetrate the substrate 2 a for supplying a heat transfer gas (back side gas) such as helium to the back side of the semiconductor wafer W. The pipe 32 is connected to a heat transfer gas supply unit 31. The flow rate of the heat transfer gas supplied from the heat transfer gas supply unit 31 to the back side of the semiconductor wafer W through the pipe 32 is controlled by a control device 60, which will be described later.

[0041] The control device 60 controls the temperature of the semiconductor wafer W adsorbed and held on the upper surface of the electrostatic chuck 6 to a temperature within a specified range by controlling the temperature of the refrigerant flowing in the flow path 2b, the power supplied to each heater 6c in the electrostatic chuck 6, and the flow rate of the heat transfer gas supplied to the back side of the semiconductor wafer W.

[0042] Shower head 16 is installed at the top of chamber 1. Shower head 16 includes a main body 16a and an upper top plate 16b forming an electrode plate. Shower head 16 is supported at the top of chamber 1 via insulating member 45. Main body 16a is formed, for example, of aluminum with an anodized surface, and upper top plate 16b is detachably supported at its bottom. Upper top plate 16b is formed, for example, of a silicon-containing material such as quartz.

[0043] A gas diffusion chamber 16c is provided inside the main body 16a. A plurality of gas outlets 16e are formed at the bottom of the main body 16a in a manner that is located below the gas diffusion chamber 16c. A plurality of gas inlets 16f are provided in the upper top plate 16b in a manner that penetrates the upper top plate 16b in the thickness direction, and each gas inlet 16f is connected to the above-mentioned gas outlet 16e. According to this structure, the processing gas supplied to the gas diffusion chamber 16c is supplied to the chamber 1 in a manner that is diffused in a spray-like manner via each gas outlet 16e and the gas inlet 16f. In addition, a temperature regulator such as a heater not shown in the figure and a pipe not shown for circulating the refrigerant is provided in the main body 16a, etc., so that the nozzle 16 can be controlled to a temperature within a desired range during the processing of the semiconductor wafer W.

[0044] The main body 16a includes a gas inlet 16g for introducing process gas into the gas diffusion chamber 16c. The gas inlet 16g is connected to one end of a pipe 15b. The other end of the pipe 15b is connected to a process gas supply source 15 via a valve V and a mass flow controller (MFC) 15a. The process gas supply source 15 is used to supply process gas for processing semiconductor wafers W. The process gas supplied from the process gas supply source 15 is supplied to the gas diffusion chamber 16c via the pipe 15b and then diffused into the chamber 1 in a shower-like manner via the gas outlets 16e and the gas inlet 16f. The valve V and the MFC 15a are controlled by a control device 60, which will be described later.

[0045] The shower head 16 is electrically connected to a variable DC power supply 42 via a low pass filter (LPF) 40 and a switch 41. The variable DC power supply 42 is capable of supplying and cutting off the DC voltage by the switch 41. The magnitude of the DC voltage supplied from the variable DC power supply 42 to the shower head 16, the on and off of the switch 41 are controlled by a control device 60 to be described later. For example, when the high frequency electric power is supplied from the high frequency power supplies 12a and 12b to the substrate 2a to generate plasma in the processing space in the chamber 1, the switch 41 is turned on by the control device 60 as needed to apply a prescribed magnitude of DC voltage to the shower head 16 functioning as an upper electrode.

[0046] An exhaust port 71 is formed in the bottom of the chamber 1. The exhaust port 71 is connected to an exhaust device 73 via an exhaust pipe 72. The exhaust device 73 has a vacuum pump, and by operating the vacuum pump, the chamber 1 can be depressurized to a prescribed vacuum degree. The exhaust flow rate of the exhaust device 73 and the like are controlled by the control device 60 to be described later. In addition, an opening portion 74 is provided in the side wall of the chamber 1, and a gate valve G for opening and closing the opening portion 74 is provided in the opening portion 74.

[0047] A deposition shield 76 is provided on the inner wall of the chamber 1 in a detachable manner along the surface of the inner wall. In addition, a deposition shield 77 is provided on the outer peripheral surface of the inner wall member 3a in a manner covering the inner wall member 3a. The deposition shields 76 and 77 are used to prevent etching byproducts (deposits) from adhering to the inner wall of the chamber 1. A conductive member (GND block) 79 grounded with DC is provided at a position of the deposition shield 76 at approximately the same height as the height of the semiconductor wafer W held in an adsorbed state on the electrostatic chuck 6. Abnormal discharge in the chamber 1 is suppressed by the conductive member 79.

[0048] In addition, an annular magnet 9 is disposed in a concentric circular shape around the chamber 1. The annular magnet 9 forms a magnetic field in the space between the shower head 16 and the substrate 2a. The annular magnet 9 is held in a rotatable manner by a rotating mechanism not shown.

[0049] The control device 60 has a processing controller 61, a user interface 62, and a storage section 63. The user interface 62 includes an input device for accepting operations of an operator or the like on the substrate processing device 100, a display device for displaying processing results of the processing controller 61 or notifications from the processing controller 61, and the like. The storage section 63 stores programs executed by the processing controller 61, and processes including conditions of each processing, and the like. The processing controller 61 executes the programs read out from the storage section 63, and controls each part of the substrate processing device 100 based on the processes stored in the storage section 63, thereby causing the substrate processing device 100 to execute a prescribed processing.

[0050] [Electrostatic Chuck 6]

[0051] Figure 2 : is a diagram showing an example of the upper surface of the electrostatic chuck 6. A focusing ring 5 is provided on the outer periphery of the electrostatic chuck 6 so as to surround the electrostatic chuck 6. The upper surface of the electrostatic chuck 6 for mounting the semiconductor wafer W is divided into a plurality of divided areas 6d. In this embodiment, the divided areas 6d are each area obtained by dividing the upper surface of the electrostatic chuck 6 into a plurality of areas in a concentric circle shape, and dividing each concentric circle area except the center area into a plurality of areas along the circumferential direction. In addition, in this embodiment, for example Figure 2 As shown in FIG. 1 , the electrostatic chuck 6 is divided into 27 divided regions 6 d . However, the number of divided regions 6 d is not limited thereto, and the electrostatic chuck 6 may be divided into 100 or more divided regions 6 d .

[0052] In this embodiment, two heaters 6c are embedded in positions corresponding to the respective divided regions 6d within the electrostatic chuck 6. The power supplied to the heaters 6c embedded in the respective divided regions 6d is independently controlled by a control board 20 described later.

[0053] [Structure of heaters in divided areas]

[0054] Figure 3 This is a diagram showing an example of the structure of the heater 6c provided in each divided area 6d. Figure 3 (A) is a diagram showing an example of a cross section of the heater 6c provided in each divided area 6d. Figure 3 (B) is a perspective view showing an example of a heater 6c provided in each divided area 6d. In this embodiment, for example Figure 3 As shown in (A) and (B), two heaters 6c-1 and 6c-2 are provided in each divided area 6d. In each divided area 6d, the heater 6c-1 is formed on one side of one of the multiple insulating layers 6b stacked together, for example, by printing, and the heater 6c-2 is formed on the other side of the insulating layer 6b, for example, by printing. Thus, the two heaters 6c-1 and 6c-2 can be easily formed in each divided area 6d without causing a short circuit between the two heaters 6c-1 and 6c-2. The two heaters 6c-1 and 6c-2 provided in each divided area 6d are, for example, Figure 3 They are connected in parallel as shown in (B) and are connected to the control board 20 via wiring 200.

[0055] In the present embodiment, the heaters 6c-1 and 6c-2 are, for example, electric resistance heaters. Further, in each of the divided regions 6d, the electric resistance values of the heaters 6c-1 and 6c-2 are preferably substantially equal to each other. In addition, as other examples, the heaters 6c-1 and 6c-2 can also be semiconductor heaters such as PTC (Positive Temperature Coefficient) thermistors, or Peltier elements, and the like.

[0056] [Structure of Control Board 20]

[0057] Figure 4 is a block diagram showing an example of the control board 20. As shown in the drawing, the control board 20 has a control section 21 and a plurality of control blocks 22-1 to 22-n. Further, in the following, in the case where the plurality of control blocks 22-1 to 22-n are collectively referred to without distinguishing each of the control blocks 22-1 to 22-n, the plurality of control blocks 22-1 to 22-n are simply referred to as control blocks 22. One control block 22 is provided for each of the divided regions 6d in the electrostatic chuck 6. Each of the control blocks 22 has a voltage control section 23, a switch 24, a current control section 25, and a current meter 26. The substrate processing apparatus 100 having the electrostatic chuck 6, the control section 21, and the heaters 6c embedded in each of the divided regions 6d is an example of a temperature control apparatus. Figure 4

[0058] The voltage control section 23 generates electric power of a prescribed voltage according to an instruction from the control section 21 and outputs it to the switch 24. The switch 24 outputs the electric power output from the voltage control section 23 according to an instruction from the control section 21 to either the current control section 25 or the current meter 26. The current control section 25 controls the total value of the electric currents supplied to each of the heaters 6c in the divided region 6d to a value instructed from the control section 21. The current meter 26 measures the total value of the electric currents flowing through each of the heaters 6c in the divided region 6d according to the electric power output from the voltage control section 23 based on an instruction from the control section 21. Further, the current meter 26 notifies the control section 21 of information on the measured total value of the electric currents.

[0059] The control section 21 causes the voltage control section 23 to generate electric power of a prescribed voltage for each of the divided regions 6d at a prescribed timing such as before the start of processing by the substrate processing apparatus 100, and controls the switch 24 so as to output the electric power from the voltage control section 23 to the current meter 26. Then, the control section 21 controls the current meter 26 so as to measure the total value of the electric currents flowing through each of the heaters 6c in the divided region 6d.

[0060] ​Here, the two heaters 6c provided in each divided area 6d within the electrostatic chuck 6 are connected in parallel. Therefore, if one of the heaters 6c in each divided area 6d is disconnected, the total current flowing through the divided area 6d is lower than the total current flowing through the divided area 6d if all heaters 6c are intact. In this embodiment, the resistance values ​​of the two heaters 6c provided in each divided area 6d are substantially equal. Therefore, if one of the heaters 6c in each divided area 6d is disconnected, the total current flowing through the divided area 6d is approximately (1 / 2) times less than the total current flowing through the divided area 6d if all heaters 6c are intact.

[0061] The control unit 21 determines whether the total value of the current measured by the ammeter 26 is greater than or equal to a first threshold value. In this embodiment, the first threshold value is, for example, a value obtained by adding a predetermined margin to (1 / 2) times the total value of the current flowing through the divided areas 6d where all heaters 6c in the divided areas 6d are not disconnected. The predetermined margin is, for example, a value predetermined based on variations in the resistance values ​​of the heaters 6c, measurement errors of the current measured by the ammeter 26, and the like. The first threshold value may also be, for example, (2 / 3) times the total value of the current flowing through the divided areas 6d where all heaters 6c in the divided areas 6d are not disconnected.

[0062] If the total value of the current measured by the ammeter 26 is less than the first threshold value, the control unit 21 determines whether the total value of the current measured by the ammeter 26 is greater than or equal to the second threshold value. In this embodiment, the second threshold value is, for example, a value obtained by adding a predetermined margin to 0. The predetermined margin is, for example, a value predetermined based on measurement errors of the current measured by the ammeter 26. The second threshold value may also be a value (1 / 3) times the total value of the current flowing through each divided area 6d when all heaters 6c in each divided area 6d are intact.

[0063] If the total value of the current measured by the ammeter 26 is less than the first threshold value and greater than the second threshold value, it is considered that a portion of the heaters 6c within the divided area 6d, that is, one of the heaters 6c, has been disconnected. Therefore, the control unit 21 controls so that the current flowing through each heater 6c embedded in the divided area 6d where the heater portion has been disconnected is greater than the current flowing through each heater 6c when all heaters 6c are intact.

[0064] Specifically, the control unit 21 controls the current control unit 25 so that the total value of the current supplied to the divided area 6d is equal to the total value of the current flowing through the divided area 6d when all the heaters 6c are not disconnected. Thus, the current flowing through each heater 6c embedded in the divided area 6d where a part of the heater 6c is disconnected becomes the current flowing through each heater 6c when all the heaters 6c are not disconnected. times.

[0065] Thus, in a segmented area 6d where a portion of the heaters 6c are disconnected, the power supplied to the remaining heaters 6c can be made substantially equal to the power supplied to the segmented area 6d if all heaters 6c were intact. Therefore, in a segmented area 6d where a portion of the heaters 6c are disconnected, the amount of heat generated by the remaining heaters 6c can be made substantially equal to the amount of heat generated by the heaters 6c in the segmented area 6d where all heaters 6c are intact. Thus, even if a portion of the heaters 6c are disconnected in each segmented area 6d, the heat generated by the disconnected heaters 6c can be compensated by the remaining heaters 6c in the segmented area 6d. Consequently, even in the event of a heater 6c disconnection, the temperature control accuracy of the semiconductor wafer W can be maintained at a high level.

[0066] When the ammeter 26 has completed measuring the total current value in all divided areas 6d, the control unit 21 controls the switch 24 in each control block 22 to output power from the voltage control unit 23 to the current control unit 25. This supplies the heater 6c in each divided area 6d with the current controlled by the current control unit 25 in the corresponding control block 22. The substrate processing apparatus 100 then executes processing in accordance with the recipe stored in the storage unit 63.

[0067] On the other hand, if there is a segmented area 6d where the total value of the current measured by the ammeter 26 is less than the second threshold value, it is considered that all the heaters 6c within the segmented area 6d are disconnected. In this case, the control unit 21 notifies the control device 60 of the segmented area 6d where all the heaters 6c are disconnected. The control device 60 notifies the operator of the substrate processing apparatus 100, etc., of the segmented area 6d where all the heaters 6c are disconnected via the user interface 62.

[0068] [Temperature control treatment]

[0069] Figure 5 The control board 20 executes the temperature control process at a predetermined timing, such as when the substrate processing apparatus 100 is installed or before the start of processing by the substrate processing apparatus 100. Figure 5 The processing is shown in the flowchart.

[0070] First, the control unit 21 selects an unselected segmented area 6d from among the multiple segmented areas 6d (S100). Then, in the control block 22 corresponding to the segmented area 6d selected in step S100, the control unit 21 causes the voltage control unit 23 to generate power of a predetermined voltage and controls the switch 24 to output the power from the voltage control unit 23 to the ammeter 26. As a result, a predetermined voltage is applied to the heater 6c within the segmented area 6d selected in step S100 via the ammeter 26 (S101).

[0071] Next, the ammeter 26 measures the total value of the current flowing through the heater 6c within the divided area 6d (S102). The ammeter 26 then notifies the control unit 21 of information indicating the total value of the measured current. The control unit 21 determines whether the total value of the current indicated by the information notified from the ammeter 26 is greater than or equal to a first threshold value (S103).

[0072] If the total current value is greater than the first threshold value (S103: Yes), the control unit 21 executes the process shown in step S107. On the other hand, if the total current value is less than the first threshold value (S103: No), the control unit 21 determines whether the total current value is less than the second threshold value (S104). If the total current value is less than the second threshold value (S104: Yes), the control unit 21 stores information indicating the first disconnection state in association with the divided area 6d selected in step S100 (S105). The control unit 21 then executes the process shown in step S107. The first disconnection state refers to a state in which all heaters 6c included in the divided area 6d are disconnected.

[0073] On the other hand, if the total current value is greater than or equal to the second threshold value (S104: No), the control unit 21 stores information indicating a second disconnection state in association with the divided region 6d selected in step S100 (S106). The second disconnection state refers to a state in which a portion of the heater 6c included in the divided region 6d is disconnected.

[0074] Next, the control unit 21 determines whether all the divided regions 6d have been selected (S107). If there are unselected divided regions 6d (S107: No), the control unit 21 executes the process shown in step S100 again.

[0075] On the other hand, if all the divided areas 6d have been selected (S107: YES), the control unit 21 determines whether any divided areas 6d are in the first disconnected state (S108). If any divided areas 6d are in the first disconnected state (S108: YES), the control unit 21 notifies the control device 60 of information indicating the divided areas 6d in the first disconnected state as an alarm (S110). The process controller 61 of the control device 60 notifies the operator of the substrate processing apparatus 100, etc., of information indicating the divided areas 6d in the first disconnected state as an alarm via the user interface 62. The control panel 20 then terminates the operations shown in this flowchart.

[0076] On the other hand, when there is no split area 6d in the first disconnection state (S108: No), the control unit 21 controls the current control unit 25 so that the value of the current supplied to the split area 6d in the second disconnection state becomes a prescribed value (S109), and the control board 20 ends the action shown in this flowchart. Specifically, the control unit 21 controls the current control unit 25 so that the current flowing through each heater 6c embedded in the split area 6d in the second disconnection state is greater than the current flowing through each heater 6c when all heaters 6c are not disconnected. For example, the control unit 21 controls the current control unit 25 so that the current supplied to the split area 6d in the second disconnection state becomes the total value of the current supplied to the split area 6d when all heaters 6c are not in a disconnection state. Thus, the current that would flow through each heater 6c if all heaters 6c were not in the disconnected state flows through the heaters 6c that are not disconnected in the divided area 6d in the second disconnected state. times the current.

[0077] Here, when current I is supplied to a divided area 6d where all heaters 6c are not disconnected, a current (1 / 2) times the current I flows through each of the two heaters 6c included in the divided area 6d. Therefore, if the resistance value of each heater 6c is R, the power supplied to each heater 6c is R×(I / 2). 2 , the entire segmented area 6d produces (RI 2 / 2) The amount of heat corresponding to the electricity.

[0078] On the other hand, the current I supplied to the divided area 6d in the second disconnected state is the same as that supplied to the divided area 6d when all the heaters 6c are not disconnected. Therefore, the current flows through the heater 6c that is not disconnected in the divided area 6d in the second disconnection state. Therefore, the heat generated in the entire divided area 6d in the second disconnected state is substantially the same as that generated by the heaters 6c in the divided area 6d where all heaters 6c are not disconnected. 2 Thus, even if a portion of the heaters 6c are disconnected in each divided area 6d, the heat generated by the disconnected heaters 6c can be compensated by the heaters 6c that are not disconnected in the divided area 6d.

[0079] The above describes an embodiment of the substrate processing apparatus 100. As is clear from the above description, the substrate processing apparatus 100 of this embodiment can maintain high accuracy in temperature control of the semiconductor wafer W even when the heater 6c is disconnected.

[0080] <Other>

[0081] In addition, the present invention is not limited to the above-described embodiments, and various modifications can be made within the scope of the gist of the invention.

[0082] For example, in the above-described embodiment, the plurality of heaters 6c provided in each divided region 6d are formed on different surfaces of one insulating layer 6b, but the disclosed technology is not limited thereto. Figure 6 As shown, the plurality of heaters 6c provided in each divided region 6d may be formed on the same surface of one insulating layer 6b. Figure 6 This is a diagram showing another example of the structure of the heater 6c provided in each divided area 6d. Figure 6 (A) is a diagram showing an example of a cross section of the heater 6c provided in each divided area 6d. Figure 6 (B) is a perspective view showing an example of the heater 6c provided in each divided area 6d.

[0083] By placing the two heaters 6c-1 and 6c-2 as Figure 6 By forming the heaters 6 c on the same surface of the insulating layer 6 b as shown, the distances from each heater 6 c to the semiconductor wafer W can be made substantially equal. This reduces the difference in the amount of heat supplied to the semiconductor wafer W when only one heater 6 c is heated and when only the other heater 6 c is heated in each divided region 6 d. Consequently, even if a portion of the heaters 6 c is disconnected, the temperature control accuracy of the semiconductor wafer W can be maintained at a high level.

[0084] Furthermore, in the above-described embodiment, two heaters 6 c connected in parallel are provided in each divided area 6 d . However, as another example, three or more heaters 6 c connected in parallel may be provided in each divided area 6 d .

[0085] In the above embodiment, multiple heaters 6c are provided on one of the multiple laminated insulating layers 6b. However, the disclosed technology is not limited to this. For example, multiple heaters 6c may be formed in parallel on the same or different surfaces of an insulating film, and the film with heaters 6c may be attached to the lower surface of the electrostatic chuck 6.

[0086] Furthermore, while the above embodiments describe substrate processing apparatus 100 as an example of a capacitively coupled parallel plate plasma processing apparatus, the disclosed technology is not limited thereto. Any apparatus that processes semiconductor wafers W and controls the temperature of the semiconductor wafers W during processing can be used. The technology disclosed in the above embodiments can also be applied to processing apparatuses that utilize plasma, such as ICP (Inductively Coupled Plasma) and microwave methods. Furthermore, the technology disclosed in the above embodiments can also be applied to apparatuses that perform heat treatments that do not utilize plasma.

Claims

1. A temperature control device, characterized in that: have: substrate; an electrostatic chuck disposed on the substrate and having a plurality of divided regions; as well as a plurality of control blocks, each of which corresponds to each of the plurality of divided regions; The electrostatic chuck includes an insulating layer having a first surface and a second surface located on an opposite side of the first surface. Each of the plurality of segmented regions comprises: a first heater disposed on the first surface of the insulating layer; and a second heater disposed on the first surface or the second surface of the insulating layer and connected in parallel with the first heater; Each control block of the plurality of control blocks comprises: an ammeter connected to the first heater and the second heater included in the corresponding divided area, the ammeter being configured to measure a total value of currents flowing through the first heater and the second heater; as well as The current control unit is configured to control, for each of the divided regions, the current supplied to the first heater and the second heater included in the divided region based on a total value of the current output from the ammeter corresponding to the divided region.

2. The temperature control device according to claim 1, characterized in that The second heater is disposed on the second surface of the insulating layer.

3. The temperature control device according to claim 1 or 2, characterized in that: The current control unit increases the current supplied to the first heater and the second heater when a total value of the current supplied to the first heater and the second heater included in the corresponding divided area is smaller than a first threshold value.

4. The temperature control device according to claim 3, characterized in that The first threshold value is a value obtained by adding a predetermined margin to half the total value of the current flowing through the first heater and the second heater included in the divided area when neither the first heater nor the second heater included in the divided area is disconnected.

5. The temperature control device according to claim 1 or 2, characterized in that: It also includes a first control unit, which is configured to control the current control unit when it is determined that any one of the first heater and the second heater included in the first divided area among the multiple divided areas is broken, so that the current flowing through each heater included in the first divided area is greater than the current flowing through each heater included in the second divided area in which all the heaters in the multiple divided areas are not broken.

6. The temperature control device according to claim 1 or 2, characterized in that: It also includes a first control unit, which is configured to: for each of the multiple divided areas, when the total value of the current flowing through the first heater and the second heater contained in the divided area is less than a first threshold value and is greater than a second threshold value which is smaller than the first threshold value, determine that one of the first heater and the second heater contained in the divided area has a broken line, and the first threshold value is less than the total value of the current flowing through the first heater and the second heater contained in the divided area when all heaters are not broken.

7. The temperature control device according to claim 6, characterized in that The first threshold value is a value obtained by adding a specified margin to half the total value of the current flowing through the first heater and the second heater contained in the divided area when neither of the first heater and the second heater contained in the divided area is disconnected, and the second threshold value is a value obtained by adding a specified margin to 0.

8. The temperature control device according to claim 5, characterized in that The first control unit controls the plurality of divided areas when it is determined that any one of the first heater and the second heater included in the divided area is disconnected, so that the current flowing through each heater included in the divided area where any one of the heaters is disconnected becomes the current flowing through each heater when all the heaters are not disconnected. times.

9. The temperature control device according to claim 5, characterized in that: The current control unit performs control so that the total value of the current supplied to the first heater and the second heater in the divided area becomes the value instructed by the first control unit. The plurality of control blocks further include: a voltage control unit configured to generate and output electric power having a predetermined voltage; an ammeter that measures the total value of the currents flowing through the first heater and the second heater within the divided area based on the power output from the voltage control unit, and notifies the first control unit of information regarding the total value of the currents; as well as A switch is configured to allow the current control unit to output the power output from the voltage control unit to the ammeter.

10. The temperature control device according to claim 9, characterized in that: The first control unit controls the voltage control unit to generate the electric power having the predetermined voltage. The first control unit controls the switch for each of the plurality of divided regions at a predetermined timing so that the power is output from the voltage control unit to the ammeter. The first control unit controls the ammeter to measure the total value of the current flowing through the first heater and the second heater in the divided area. When the ammeter completes measuring the total value of the current for the plurality of divided regions, the first control unit controls the switches of the respective control blocks so that the power is output from the voltage control unit to the current control unit.

11. The temperature control device according to claim 5, characterized in that: The first control unit is configured to notify an external device in response to a determination that a disconnection has occurred between the first heater and the second heater.

12. The temperature control device according to claim 1 or 2, characterized in that: The first heater and the second heater are resistive heaters.

13. The temperature control device according to claim 1 or 2, characterized in that: The first heater and the second heater are semiconductor heaters.

14. The temperature control device according to claim 1 or 2, characterized in that: The first heater and the second heater are Peltier elements.

15. The temperature control device according to claim 1 or 2, characterized in that: The current control unit independently controls current for the first heater and the second heater included in the corresponding divided area.

16. The temperature control device according to claim 1 or 2, characterized in that: In the plurality of divided regions, resistance values ​​of the first heater and the second heater are identical to each other.

17. The temperature control device according to claim 1 or 2, characterized in that: The plurality of control blocks are provided on at least one control board.

18. A temperature control device, characterized in that: have: A mounting table for mounting a substrate to be processed; a heater, wherein a plurality of heaters are included in each of the divided areas inside the mounting table, each of the divided areas being obtained by dividing the upper surface of the mounting table into a plurality of areas; as well as a control unit that controls the heater, wherein the control unit determines whether a portion of the heater included in each divided area is broken based on a total value of current flowing through the plurality of heaters included in each divided area. The plurality of heaters contained in each of the divided areas are connected in parallel. The control unit controls each of the divided areas when it is determined that a part of the heaters included in the divided area is broken, so that the current flowing through each heater included in the divided area where a part of the heaters is broken and different from the heaters that are broken is greater than the current flowing through each heater when all the heaters are not broken.

19. The temperature control device according to claim 18, characterized in that The mounting platform includes a plurality of stacked insulating layers, Each of the plurality of heaters included in the divided region is arranged on a different surface of one of the plurality of insulating layers.

20. The temperature control device according to claim 18 or 19, characterized in that: Two heaters connected in parallel are embedded in each of the divided areas. For each of the divided areas, the control unit determines that a part of the heaters embedded in the divided area has a broken wire when the total value of the current flowing through the two heaters embedded in the divided area is less than a first threshold value and is greater than a second threshold value which is smaller than the first threshold value, wherein the first threshold value is smaller than the total value of the current flowing through the two heaters embedded in the divided area when all the heaters are not broken.

21. The temperature control device according to claim 20, characterized in that The heater is a resistance heater, The first threshold value is a value obtained by adding a predetermined margin to a value half the total value of the current flowing through the two heaters embedded in the divided area when all heaters are not disconnected. The second threshold value is a value obtained by adding a predetermined margin to 0.

22. The temperature control device according to claim 21, characterized in that The control unit controls each of the divided areas when it is determined that a portion of the heaters embedded in the divided area is broken, so that the current flowing through each heater in the divided area where the portion of the heaters embedded in the divided area is broken becomes the current flowing through each heater when all the heaters are not broken. times.

23. A temperature control method for controlling the temperature of a substrate to be processed placed on a mounting table, the temperature control method comprising the following steps: measuring a total value of current flowing through a plurality of heaters included in and connected in parallel to each of the divided regions within the mounting table, wherein each of the divided regions is obtained by dividing the upper surface of the mounting table into a plurality of regions; determining whether or not a portion of the heaters included in each of the divided areas is broken based on a total value of currents flowing through a plurality of heaters included in each of the divided areas and connected in parallel; as well as For each of the divided areas, when it is determined that a part of the heaters included in the divided area is broken, control is performed so that the current flowing through each heater included in the divided area where a part of the heaters is broken is greater than the current flowing through each heater when all the heaters are not broken.

24. The temperature control method according to claim 23, characterized in that: The mounting platform includes a plurality of stacked insulating layers, Each of the plurality of heaters included in the divided region is arranged on a different surface of one of the plurality of insulating layers.

25. A mounting table for mounting a substrate to be processed, wherein: A plurality of heaters are provided, wherein the plurality of heaters are contained in respective divided regions inside the mounting table, wherein the respective divided regions are obtained by dividing the upper surface of the mounting table into a plurality of regions, The plurality of heaters included in each of the divided areas are connected in parallel, in, For each of the divided regions, the current supplied to the plurality of heaters is controlled based on a total value of the current output from the plurality of heaters connected in parallel and included in the divided region.

26. The mounting table according to claim 25, wherein: The mounting platform includes a plurality of stacked insulating layers, Each of the plurality of heaters included in the divided region is arranged on a different surface of one of the plurality of insulating layers.

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