Substrate holding mechanism, substrate processing apparatus, and control method

Abstract

To provide a substrate holding mechanism, a substrate processing apparatus, and a control method for improving the mounting accuracy of a substrate.SOLUTION: A mounting table made of a dielectric material and having a substrate supporting surface configured to support a processing target substrate; a chuck electrode provided in the mounting table and configured to electrostatically attract the processing target substrate; a chuck power supply configured to apply a voltage to the chuck electrode; and a controller configured to control the chuck power supply, wherein the controller is configured to perform a process of applying a first voltage from the chuck power supply to the chuck electrode before the processing target substrate is mounted on the substrate support surface, and a process of applying a second voltage different from the first voltage from the chuck power supply to the chuck electrode after the processing target substrate is mounted on the substrate support surface.SELECTED DRAWING: Figure 2

Description

[Technical Field]

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

[0002] Patent Document 1 discloses a substrate holding mechanism for holding a substrate to be processed when a conductive film is formed, the mechanism comprising: a stage made of a dielectric material for supporting the substrate to be processed; a chuck electrode provided within the stage for electrostatically attracting the substrate to be processed; and a heater for heating the stage; when a DC voltage is applied to the chuck electrode, the substrate to be processed is electrostatically attracted to the surface of the stage by the Johnson-Rahbek force; the stage has a ring-shaped contact area that functions to prevent a source gas for forming the conductive film from flowing around to the back side of the substrate to be processed; and a ring-shaped groove provided outside the contact area on the surface of the stage, in which a conductive deposition film made of the source gas can accumulate. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2020-88195 Summary of the Invention [Problem to be solved by the invention]

[0004] In one aspect, the present disclosure provides a substrate holding mechanism, a substrate processing apparatus, and a control method that improve substrate placement accuracy. [Means for solving the problem]

[0005] In order to solve the above problem, according to one aspect, a substrate holding mechanism can be provided, comprising: a mounting table made of a dielectric material and having a substrate support surface that supports a workpiece substrate; a chuck electrode provided within the mounting table for electrostatically attracting the workpiece substrate; a chuck power supply that applies a voltage to the chuck electrode; and a controller that controls the chuck power supply, wherein the controller is configured to apply a first voltage from the chuck power supply to the chuck electrode before the workpiece substrate is placed on the substrate support surface, and apply a second voltage, different from the first voltage, from the chuck power supply to the chuck electrode after the workpiece substrate has been placed on the substrate support surface. [Effects of the Invention]

[0006] According to one aspect, it is possible to provide a substrate holding mechanism, a substrate processing apparatus, and a control method that improve the placement accuracy of the substrate W. Also, by improving the placement accuracy of the substrate W, it is possible to suppress the disruption of the suction distribution due to misalignment of the substrate W, and to prevent the formation of a film on the back surface of the substrate W. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 1 is a schematic diagram illustrating an example of the configuration of a substrate processing apparatus. [Figure 2] 10 is a flowchart showing an example of a method for controlling the substrate processing apparatus. [Figure 3] 10 is an example of a graph showing changes in chuck voltage, stage position, and heater power in an example of a control method. [Figure 4] 10 is a flowchart showing an example of another control method for the substrate processing apparatus. [Figure 5] 10 is an example of a graph showing changes in chuck voltage, stage position, and heater power in an example of another control method. [Figure 6] 6 is a graph showing the variation in the center position of a substrate W placed on a table. DETAILED DESCRIPTION OF THE INVENTION

[0008] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. In the drawings, the same components are denoted by the same reference numerals, and redundant explanations may be omitted.

[0009] [Substrate Processing Apparatus] A substrate processing apparatus 100 according to this embodiment will be described with reference to Fig. 1. Fig. 1 is a schematic diagram illustrating an example of the configuration of the substrate processing apparatus 100. The substrate processing apparatus 100 performs desired substrate processing (e.g., film formation processing, etching processing, etc.) on a substrate (substrate to be processed) W. For example, the substrate processing apparatus 100 is an apparatus that forms a film (e.g., a conductive film containing metal atoms) on the substrate W by a thermal CVD (Chemical Vapor Deposition) method, a thermal ALD (Atomic Layer Deposition) method, a plasma CVD (Plasma-enhanced Chemical Vapor Deposition) method, a plasma ALD (Plasma-enhanced Atomic Layer Deposition) method, etc. in a processing chamber under reduced pressure.

[0010] As shown in FIG. 1, the substrate processing apparatus 100 includes a chamber 1, a mounting table 2, a shower head 30, an exhaust unit 40, a gas supply mechanism 50, an RF power supply unit 80, and a control unit 9.

[0011] The chamber (also referred to as a processing vessel) 1 is made of a metal such as aluminum and has a generally cylindrical shape. The chamber 1 accommodates a substrate W. A loading / unloading port 11 is formed in a sidewall of the chamber 1 for loading and unloading the substrate W, and the loading / unloading port 11 is opened and closed by a gate valve 12. An annular exhaust duct 13 with a rectangular cross section is provided above the main body of the chamber 1. A slit 13a is formed along the inner peripheral surface of the exhaust duct 13. An exhaust port 13b is formed in the outer wall of the exhaust duct 13. A ceiling wall 14 is provided on the upper surface of the exhaust duct 13 to close the upper opening of the chamber 1 via an insulating member 16. A seal ring 15 hermetically seals the space between the exhaust duct 13 and the insulating member 16. A partition member 17 divides the interior of the chamber 1 into upper and lower sections when the mounting table 2 is raised to a processing position (described later).

[0012] The mounting table (also referred to as a stage) 2 supports the substrate W horizontally within the chamber 1. The mounting table 2 is formed in a disk shape corresponding in size to the substrate W, and is supported by a support member 23. A recess 2b for accommodating the substrate W is formed on the upper surface of the mounting table 2. The bottom surface of the recess 2b serves as a substrate support surface that supports the rear surface of the substrate W. The sidewalls of the recess 2b limit horizontal displacement of the substrate W when the substrate W is placed on the substrate support surface. The mounting table 2 is made of a dielectric material, for example, a ceramic such as aluminum nitride (AlN).

[0013] A chuck electrode 3 (3a, 3b) for electrostatically attracting the substrate W is embedded in the mounting table 2 near its surface, forming an electrostatic chuck. The chuck electrode 3 is connected to a chuck power supply 4 via a power supply line. The chuck power supply 4 applies (supplies) a voltage to the chuck electrode 3 (3a, 3b). While the chuck electrode 3 is described as a bipolar electrostatic chuck having electrodes 3a and 3b, the present invention is not limited thereto and may be a monopolar electrostatic chuck. The electrostatic chuck may also be an electrostatic chuck that attracts the substrate W by Coulomb force. The electrostatic chuck may also be an electrostatic chuck that attracts the substrate W by Johnsen-Rahbek force. The chuck electrode 3 may also function as a ground electrode for plasma.

[0014] A heater 5 for heating the mounting table 2 is embedded below the chuck electrode 3 inside the mounting table 2. The heater 5 is connected to a heater power supply 6 via a power supply line. The heater power supply 6 supplies electric power (heater power) to the heater 5. A temperature sensor (not shown), such as a thermocouple, is provided near the upper surface of the mounting table 2. A control unit 9 controls the electric power (heater power) supplied from the heater power supply 6 to the heater 5 based on the detected value of the temperature sensor. This controls the temperature of the mounting table 2 to a predetermined temperature. Furthermore, the temperature of the substrate W placed on the mounting table 2 is controlled to a predetermined temperature.

[0015] The substrate holding mechanism includes a mounting table 2 made of a dielectric material, a chuck electrode 3 provided within the mounting table 2 for electrostatically attracting the substrate W, a heater 5 provided within the mounting table 2 for heating the mounting table 2, a chuck power supply 4 for applying a voltage to the chuck electrode 3, a heater power supply 6 for supplying power to the heater 5, and a control unit 9 for controlling the chuck power supply 4 and the heater power supply 6.

[0016] A support member 23 that supports the mounting table 2 is provided on the bottom surface of the mounting table 2. The support member 23 extends from the center of the bottom surface of the mounting table 2 to below the chamber 1, passing through a hole formed in the bottom wall of the chamber 1, and its lower end is connected to a lifting mechanism 24. The lifting mechanism 24 raises and lowers the mounting table 2 via the support member 23 between a processing position shown in FIG. 1 and a transfer position shown by a two-dot chain line below that position, where the substrate W can be transferred. A flange 25 is attached to the support member 23 below the chamber 1, and a bellows 26 that separates the atmosphere inside the chamber 1 from the outside air and expands and contracts as the mounting table 2 is raised and lowered is provided between the bottom surface of the chamber 1 and the flange 25.

[0017] Three lift pins 27 (only two are shown in FIG. 1 ) are provided near the bottom surface of the chamber 1 so as to protrude upward from a lift plate 27a. The lift pins 27 are raised and lowered via the lift plate 27a by a lift mechanism 28 provided below the chamber 1. The lift pins 27 are inserted into through holes 2a provided in the mounting table 2 at the transfer position, and are capable of protruding and retracting from the upper surface of the mounting table 2. By raising and lowering the lift pins 27, the substrate W is transferred between the transfer mechanism (not shown) and the mounting table 2.

[0018] The shower head 30 supplies a process gas into the chamber 1 in a shower-like manner. The shower head 30 is made of metal and is disposed opposite the mounting table 2. It has approximately the same diameter as the mounting table 2. The shower head 30 includes a main body 31 fixed to the ceiling wall 14 of the chamber 1 and a shower plate 32 connected below the main body 31. A gas diffusion space 33 is formed between the main body 31 and the shower plate 32. A gas inlet hole 36 is provided in the gas diffusion space 33, penetrating the center of the main body 31 and the ceiling wall 14 of the chamber 1. A downwardly protruding annular protrusion 34 is formed on the periphery of the shower plate 32. A gas outlet hole 35 is formed on the inner flat surface of the annular protrusion 34. When the mounting table 2 is in the processing position, a processing space 38 is formed between the mounting table 2 and the shower plate 32. The upper surface of the mounting table 2 and the annular protrusion 34 are adjacent to each other, forming an annular gap 39.

[0019] The exhaust unit 40 exhausts the interior of the chamber 1. The exhaust unit 40 has an exhaust pipe 41 connected to the exhaust port 13b and an exhaust mechanism 42 connected to the exhaust pipe 41 and having a vacuum pump, a pressure control valve, etc. During processing, gas inside the chamber 1 reaches the exhaust duct 13 through the slit 13a, and is exhausted from the exhaust duct 13 through the exhaust pipe 41 by the exhaust mechanism 42. The exhaust mechanism 42 has a pressure control valve, a vacuum pump, a gas trap mechanism, etc. The pressure control valve adjusts the pressure inside the chamber 1. The vacuum pump includes a turbomolecular pump, a dry pump, or a combination thereof. The gas trap mechanism traps the exhaust gas.

[0020] The gas supply mechanism 50 supplies a processing gas into the chamber 1. The gas supply mechanism 50 has a gas supply unit 51. The gas supply unit 51 is configured to be able to switch between supplying a plurality of gases. The gas supply unit 51 is connected to the gas inlet hole 36 via a gas supply line 52. The processing gas supplied from the gas supply unit 51 is supplied to the processing space 38 via the gas supply line 52, the gas inlet hole 36, the gas diffusion space 33, and the gas outlet hole 35.

[0021] In addition, a purge gas supply mechanism (not shown) may be provided to supply a purge gas (e.g., N2 gas) into the chamber 1 (e.g., the space within the chamber 1 that is formed below the mounting table 2 when the mounting table 2 is placed in the processing position).

[0022] The substrate processing apparatus 100 is a capacitively coupled plasma apparatus, in which the mounting table 2 serves as a lower electrode and the shower head 30 serves as an upper electrode. The mounting table 2 serving as the lower electrode is grounded via a capacitor (not shown).

[0023] The shower head 30 serving as the upper electrode is supplied with radio frequency power (hereinafter also referred to as "RF power") by an RF power supply unit 80. The RF power supply unit 80 includes a power feed line 81, a matching box 82, and a radio frequency power supply 83. The radio frequency power supply 83 is a power supply that generates radio frequency power. The radio frequency power has a frequency suitable for generating plasma. The frequency of the radio frequency power is, for example, a frequency in the range of 450 KHz to 100 MHz. The radio frequency power supply 83 is connected to the main body 31 of the shower head 30 via the matching box 82 and the power feed line 81. The matching box 82 includes a circuit for matching the output reactance of the radio frequency power supply 83 with the reactance of the load (upper electrode). Note that, although the RF power supply unit 80 has been described as supplying radio frequency power to the shower head 30 serving as the upper electrode, the present invention is not limited thereto. The RF power supply unit 80 may also be configured to supply radio frequency power to the mounting table 2 serving as the lower electrode.

[0024] The control unit 9 is, for example, a computer, and includes a CPU (Central Processing Unit), RAM (Random Access Memory), ROM (Read Only Memory), an auxiliary storage device, etc. The CPU operates based on a program stored in the ROM or the auxiliary storage device, and controls the operation of the substrate processing apparatus 100. The control unit 9 may be provided inside or outside the substrate processing apparatus 100. When the control unit 9 is provided outside the substrate processing apparatus 100, the control unit 9 can control the substrate processing apparatus 100 via communication means such as wired or wireless.

[0025] [Substrate Processing Apparatus Control Method] Next, an example of a method for controlling the substrate processing apparatus 100 according to this embodiment will be described with reference to Fig. 2. Fig. 2 is a flowchart showing an example of the method for controlling the substrate processing apparatus 100.

[0026] In step S101, the substrate W is transferred to the chamber 1. Here, the mounting table 2 is placed at the transfer position (see the two-dot chain line in FIG. 1). The control unit 9 opens the gate valve 12. Next, the control unit 9 controls a transfer mechanism (not shown) provided in a vacuum transfer chamber (not shown) to transfer the substrate W into the chamber 1 through the transfer port 11 and place the substrate W above the mounting table 2.

[0027] A purge gas is supplied into the vacuum transfer chamber, and the pressure therein is set to a predetermined pressure (e.g., a pressure greater than 1 Torr), which is higher than the pressure in chamber 1 of the substrate processing apparatus 100. That is, by opening the gate valve 12, a purge gas (e.g., N2 gas) flows from the vacuum transfer chamber into chamber 1 through the loading / unloading port 11. This prevents processing gases and the like remaining in chamber 1 of the substrate processing apparatus 100 from flowing into the vacuum transfer chamber. Furthermore, by opening the gate valve 12, the pressure in chamber 1 of the substrate processing apparatus 100 (environmental pressure of the mounting table 2) also increases, and the pressure therein reaches a predetermined pressure (e.g., a pressure greater than 1 Torr).

[0028] As a result, molecules of the purge gas and molecules of the process gas remaining in the chamber 1 are adsorbed onto the surface of the substrate W and the surface of the mounting table 2. In particular, molecules of the purge gas and molecules of the process gas remaining in the chamber 1 are adsorbed onto the back surface of the substrate W and the substrate support surface of the mounting table 2. When the substrate W is placed on the substrate support surface of the mounting table 2, the surface-adsorbed molecules of the purge gas and / or residual gas reduce the frictional resistance between the back surface of the substrate W and the substrate support surface of the mounting table 2. Therefore, when the back surface of the substrate W is placed on the substrate support surface of the mounting table 2, the substrate W may slide, resulting in a decrease in placement accuracy.

[0029] In step S102, the substrate W is supported by the lift pins 27. Here, the control unit 9 controls the lifting mechanism 28 to raise the lift pins 27. As a result, the substrate W supported by the transport mechanism is supported by the lift pins 27. Thereafter, when the transport mechanism that has transferred the substrate W to the lift pins 27 retreats from the load / unload port 11, the control unit 9 closes the gate valve 12.

[0030] In step S103, the pressure in the chamber 1 is reduced. The control unit 9 controls the exhaust mechanism 42 to reduce the pressure in the chamber 1 to a predetermined pressure. Specifically, the pressure in the chamber 1 of the substrate processing apparatus 100 (environmental pressure of the mounting table 2) is set to a pressure of 1 Torr or less (e.g., 0.67 Torr).

[0031] This reduces the number of molecules of the purge gas and / or residual gas adsorbed on the surface of the substrate W and the surface of the mounting table 2. Furthermore, when the substrate W is placed on the substrate support surface of the mounting table 2, it is possible to suppress a decrease in the frictional resistance between the back surface of the substrate W and the substrate support surface of the mounting table 2. Therefore, when the back surface of the substrate W is placed on the substrate support surface of the mounting table 2, it is possible to suppress sliding of the substrate W.

[0032] The exhaust mechanism 42 is also provided with a gas trap mechanism (not shown) for trapping the processing gas. To prevent contamination from the gas trap mechanism into the chamber 1 or the vacuum transfer chamber, a purge gas is continuously supplied into the chamber 1 at a flow rate equal to or greater than a predetermined lower limit.

[0033] In step S104, a pre-chuck voltage V1 is applied to the chuck electrodes 3 (3a, 3b). Here, the control unit 9 controls the chuck power supply 4 to apply the pre-chuck voltage V1 (first voltage) to the chuck electrodes 3 (3a, 3b). Here, the pre-chuck voltage V1 is a voltage smaller than an attraction voltage V2 (see step S106) for electrostatically attracting the substrate W, which will be described later. The pre-chuck voltage V1 generates a weak attraction force that suppresses sliding of the substrate W when the substrate W is placed on the substrate support surface. The pre-chuck voltage V1 (first voltage) is preferably a voltage equal to or smaller than half the attraction voltage V2 (second voltage).

[0034] In step S105, the substrate W is brought into contact with the mounting table 2. Here, the control unit 9 controls the lifting mechanism 24 to raise the mounting table 2 (including the support member 23 and flange 25). At this time, the height of the lift pins 27 is maintained at their current position. That is, the lift pins 27 that hold the substrate W are lowered relatively to the mounting table 2. As a result, the lift pins 27 are accommodated in the through holes 2a of the mounting table 2, the substrate W is accommodated in the recess 2b of the mounting table 2, and the back surface of the substrate W is brought into contact with the substrate support surface of the mounting table 2 (the bottom surface of the recess 2b).

[0035] Although the method of bringing the substrate W into contact with the mounting table 2 has been described by taking as an example the case where the lifting mechanism 24 raises the mounting table 2, the method is not limited to this. Alternatively, the lifting mechanism 28 may lower the lift pins 27, which hold the substrate W relative to the mounting table 2, so that the lift pins 27 are accommodated in the through holes 2a of the mounting table 2, the substrate W is accommodated in the recess 2b of the mounting table 2, and the back surface of the substrate W comes into contact with the substrate support surface of the mounting table 2 (the bottom surface of the recess 2b).

[0036] Here, a pre-chuck voltage V1 is applied to the chuck electrode 3 in advance, thereby preventing the substrate W placed on the substrate support surface of the mounting table 2 from sliding.

[0037] In step S106, an attraction voltage V2 is applied to the chuck electrode 3 (3a, 3b). Here, the control unit 9 controls the chuck power supply 4 to apply an attraction voltage V2 (second voltage) to the chuck electrode 3 (3a, 3b). Here, the attraction voltage V2 is a voltage greater than the pre-chuck voltage V1 (see step S104). The attraction voltage V2 electrostatically attracts the substrate W placed on the substrate support surface and generates a strong attraction force that prevents the processing gas from flowing around to the backside of the substrate W in the substrate processing (S107) described later.

[0038] Here, by applying an attraction voltage V2 to the chuck electrode 3, the substrate W is strongly electrostatically attracted to the mounting table 2 (electrostatic chuck).

[0039] The attracting voltage V2 may be configured, for example, such that an attracting voltage V21 (third voltage) higher than the pre-chuck voltage V1 (first voltage) is first applied to the chuck electrode 3, and then an attracting voltage V22 (second voltage) higher than the attracting voltage V21 (third voltage) is applied to the chuck electrode 3. Details will be described later with reference to FIG. 3.

[0040] In step S107, substrate processing is performed. Here, the mounting table 2 is placed at the processing position (see FIG. 1). The control unit 9 controls the gas supply mechanism 50 to supply the processing gas to the processing space 38, and controls the RF power supply unit 80 to generate plasma of the processing gas in the processing space 38, thereby performing the desired processing on the substrate W.

[0041] In step S108, the substrate W is unloaded from the chamber 1. Here, the control unit 9 controls the lifting mechanism 28 to lower the mounting table 2 to the transfer position (see the two-dot chain line in FIG. 1). The control unit 9 also controls the chuck power supply 4 to stop applying voltage to the chuck electrode 3 and release electrostatic adsorption. The control unit 9 also controls the lifting mechanism 28 to raise the lift pins 27 and / or controls the lifting mechanism 28 to lower the mounting table 2, thereby supporting the substrate W placed on the mounting table 2 with the lift pins 27. The control unit 9 opens the gate valve 12. Next, the control unit 9 controls a transfer mechanism (not shown) provided in a vacuum transfer chamber (not shown) to unload the substrate W.

[0042] As described above, according to the control method for the substrate processing apparatus 100 shown in FIG. 2, the substrate W can be prevented from sliding and can be attracted to the mounting table 2 (electrostatic chuck).

[0043] If the substrate W slides when being placed on the mounting table 2, the edge of the substrate W may come into contact with the sidewall of the recess 2b. If the edge of the substrate W is in contact with the sidewall of the recess 2b and is strongly attracted to the electrostatic chuck, the edge of the substrate W may be damaged. In contrast, the control method shown in Fig. 2 prevents the substrate W from sliding, thereby preventing the edge of the substrate W from being damaged.

[0044] Furthermore, there is a risk that the suction distribution will be disrupted due to misalignment of the substrate W. If the suction distribution is disrupted, the uniformity of the temperature distribution on the substrate W will be disrupted, and the uniformity of the film thickness in the film formation process on the substrate W may be reduced. In contrast, the control method shown in Fig. 2 prevents the substrate W from sliding, thereby improving the uniformity of the suction distribution on the substrate W, improving the uniformity of the temperature distribution on the substrate W, and improving the uniformity of the film thickness formed on the substrate W.

[0045] Furthermore, positional deviation of the substrate W may cause a disruption in the suction distribution, which may result in the formation of a film on the rear surface of the substrate W. In contrast, the control method shown in Fig. 2 prevents the substrate W from sliding, thereby improving the uniformity of the suction distribution of the substrate W and preventing the formation of a film on the rear surface of the substrate W.

[0046] 3 is an example of a graph showing changes in chuck voltage, stage position, and heater power in an example of a control method. The horizontal axis represents time. The vertical axis represents the chuck voltage (shown by a solid line) which is the voltage applied to the chuck electrode 3, the stage position (shown by a dashed line) which is the height position of the mounting table 2, and the heater power (shown by a dotted line) which is the power supplied from the heater power supply 6 to the heater 5.

[0047] Before the substrate W comes into contact with the substrate support surface of the mounting table 2, the control unit 9 controls the chuck power supply 4 to set the chucking voltage to a pre-chuck voltage V1 (first voltage) (see step S104). The control unit 9 also controls the lifting mechanism 24 to gently raise the stage position. Then, at the timing indicated by the arrow in FIG. 3, the substrate W comes into contact with the substrate support surface of the mounting table 2 (see step S105).

[0048] When the substrate W comes into contact with the substrate support surface of the mounting table 2, the control unit 9 controls the chuck power supply 4 to set the chucking voltage to an attraction voltage V21 (third voltage). The attraction voltage V21 (third voltage) is higher than the pre-chuck voltage V1 (first voltage) and lower than the attraction voltage V22 (second voltage). The control unit 9 also controls the lifting mechanism 24 to raise the stage position to the processing position (see the position of the mounting table 2 indicated by the solid line in FIG. 1).

[0049] By attracting the substrate W with an attracting voltage V21 (third voltage) that is greater than the pre-chuck voltage V1 (first voltage), the thermal conductivity between the mounting table 2 and the substrate W is improved. Furthermore, by placing the substrate W on the mounting table 2, heat is transferred from the mounting table 2 to the substrate W, causing the temperature of the substrate W to rise. In other words, the substrate W thermally expands. By applying an attracting voltage V21 (third voltage) that is less than the attracting voltage V22 (second voltage) to the chuck electrode 3, the substrate W can be attracted to the mounting table 2 while alleviating stress caused by thermal expansion of the substrate W.

[0050] Furthermore, a heat transfer gas (e.g., He gas) is filled into the gap between the back surface of the substrate W and the substrate mounting surface of the mounting table 2 from a heat transfer gas supply unit (not shown). The substrate mounting surface has a seal band, which is a ring-shaped convex portion that contacts the outer edge of the back surface of the substrate W. The seal band and the back surface of the substrate W are tightly attached by the attraction force of the attraction voltage V21 (third voltage), thereby preventing leakage of the heat transfer gas. In other words, the attraction voltage V21 (third voltage) generates an attraction force that prevents leakage of the heat transfer gas supplied into the gap between the back surface of the substrate W and the substrate mounting surface of the mounting table 2.

[0051] Furthermore, based on the detection value of a temperature sensor provided near the upper surface of the mounting table 2, the control unit 9 controls the electric power (heater power) supplied from the heater power supply 6 to the heater 5 so that the detection value of the temperature sensor becomes a predetermined temperature (specifically, the substrate processing temperature in step S107). Here, heat is transferred from the mounting table 2 to the substrate W, causing the surface temperature of the mounting table 2 to decrease and the heater power of the heater power supply 6 to increase. Then, when the temperature of the substrate W approaches the surface temperature of the mounting table 2 to approach the predetermined temperature, the heater power decreases, and then the heater power becomes stable (equilibrium state).

[0052] The control unit 9 changes the chucking voltage from the attracting voltage V21 (third voltage) to the attracting voltage V22 (second voltage) when the surface temperature of the mounting table 2 is the substrate processing temperature in step S107 (specifically, 400° C. or higher).

[0053] Alternatively, after the substrate W is placed on the mounting table 2 and the heater power of the heater power supply 6 supplied to the heater 5 becomes stable, the control unit 9 changes the chucking voltage from the clamping voltage V21 (third voltage) to the clamping voltage V22 (second voltage). For example, after the substrate W is placed on the mounting table 2, when the heater power exceeds the rising peak and the amount of change in the heater power falls within a predetermined range, the control unit 9 changes the chucking voltage from the clamping voltage V21 (third voltage) to the clamping voltage V22 (second voltage).

[0054] As a result, by setting the chucking voltage to the attracting voltage V22 (second voltage) after the thermal expansion of the substrate W has stabilized, it is possible to prevent cracks or the like from occurring in the substrate W due to stress caused by the thermal expansion of the substrate W. The heat transfer gas may be used even after the heater power has stabilized. For example, the substrate is processed after the temperature state has stabilized, and the use of the heat transfer gas can mitigate temperature rises and variations caused by plasma. In this case, too, the attracting voltage V22 can prevent a film from being formed on the back surface of the substrate W.

[0055] [Another Control Method of Substrate Processing Apparatus] Next, another example of a method for controlling the substrate processing apparatus 100 will be described with reference to Fig. 4. Fig. 4 is a flowchart showing another example of a method for controlling the substrate processing apparatus 100.

[0056] In step S201, the substrate W is transported to the chamber 1. In step S202, the substrate W is supported by the lift pins 27. In step S203, the pressure inside the chamber 1 is reduced. Note that the processes from steps S201 to S203 are the same as the processes from steps S101 to S103, and therefore, redundant explanations will be omitted.

[0057] In step S204, the substrate W is brought into contact with the mounting table 2. In step S205, an attraction voltage V3 is applied to the chuck electrode 3. In step S206, substrate processing is performed. In step S207, the substrate W is unloaded from the chamber 1. Note that the processes from steps S204 to S207 are the same as the processes from steps S105 to S108, and therefore, redundant explanations will be omitted.

[0058] That is, in the example of another control method shown in Fig. 4, the process of step S104 is omitted compared to the example of the control method shown in Fig. 2. The other processes are similar.

[0059] 5 is an example of a graph showing changes in chuck voltage, stage position, and heater power in another example of control method. The horizontal axis represents time. The vertical axis represents the chuck voltage (shown by a solid line) which is the voltage applied to the chuck electrode 3, the stage position (shown by a dashed line) which is the height position of the mounting table 2, and the heater power (shown by a dotted line) which is the power supplied from the heater power supply 6 to the heater 5.

[0060] Before the substrate W comes into contact with the substrate support surface of the mounting table 2, the control unit 9 controls the lifting mechanism 24 to raise the stage position and reduce the distance between the substrate W and the mounting table 2. This causes the substrate W to be heated by radiation. Thereafter, the control unit 9 controls the lifting mechanism 24 to gently raise the stage position. Then, at the timing indicated by the arrow in FIG. 5, the substrate W comes into contact with the substrate support surface of the mounting table 2 (see step S204).

[0061] After the substrate W comes into contact with the substrate support surface of the mounting table 2, the control unit 9 controls the lifting mechanism 24 to raise the stage position to the processing position (see the position of the mounting table 2 indicated by the solid line in FIG. 1).

[0062] Furthermore, after the substrate W comes into contact with the substrate support surface of the mounting table 2 and the surface temperature of the mounting table 2 becomes stable at the substrate processing temperature in step S107, or after the heater power supplied from the heater power supply 6 to the heater 5 becomes stable, the control unit 9 sets the chucking voltage to the attraction voltage V3.

[0063] Such control can alleviate stress caused by thermal expansion of the substrate W. On the other hand, when the substrate W comes into contact with the substrate support surface of the mounting table 2, the substrate W may slide.

[0064] Fig. 6 is a graph showing the variation in the center position of a substrate W placed on the mounting table 2. Fig. 6(a) shows an example in which a substrate W is placed on the mounting table 2 using the control method shown in Fig. 2 and Fig. 3. Fig. 6(b) shows an example in which a substrate W is placed on the mounting table 2 using another control method shown in Fig. 4 and Fig. 5. Here, the substrate W is placed multiple times, and the center positions of the substrate W are plotted.

[0065] As shown in FIG. 6(b), in the other control methods shown in FIGS. 4 and 5, it is shown that the substrate W slides when placed on the mounting table 2. In FIG.

[0066] In contrast, as shown in FIG. 6(a), the control methods shown in FIGS. 2 and 3 suppress the sliding of the substrate W.

[0067] The above describes the control method for the substrate processing apparatus 100, but the present disclosure is not limited to the above embodiments, and various modifications and improvements are possible within the scope of the gist of the present disclosure as described in the claims. [Explanation of symbols]

[0068] W substrate (substrate to be processed) 100 Substrate processing apparatus 1 chamber 2 Mounting table 2a Through hole 2b Recess 3 Chuck electrode 3a Chuck electrode 3b Chuck electrode 4 Chuck power supply 5 Heater 6 Heater power supply 9 Control Unit 11 Loading / unloading entrance 12 Gate valve 13 Exhaust duct 13a Slit 13b Exhaust port 14 Ceiling wall 15 Seal ring 16 Insulating material 17 Compartment members 23 Support member 24 Lifting mechanism 25 Tsuba 26 Bellows 27 Lift Pin 27a Lifting board 28 Lifting mechanism 30 shower head 31 Main body 32 shower plate 33 Gas diffusion space 34 Annular protrusion 35 Gas outlet hole 36 Gas inlet 38 Processing Space 39 Annular gap 40 Exhaust section 41 Exhaust piping 42 Exhaust mechanism 50 Gas supply mechanism 51 Gas supply section 52 Gas supply line 80 RF power supply 81 Power Supply Line 82 Matching box 83 High frequency power supply

Claims

1. a mounting table made of a dielectric material and having a substrate support surface for supporting a substrate to be processed; a chuck electrode provided in the mounting table for electrostatically attracting the substrate to be processed; a chuck power supply that applies a voltage to the chuck electrode; a control unit that controls the chuck power supply, The control unit applying a first voltage from the chuck power supply to the chuck electrode before placing the substrate to be processed on the substrate support surface; applying a second voltage, different from the first voltage, from the chuck power supply to the chuck electrode after the substrate to be processed is placed on the substrate support surface. Board holding mechanism.

2. the first voltage is lower than the second voltage; The substrate holding mechanism of claim 1 .

3. The first voltage is equal to or less than half of the second voltage. The substrate holding mechanism of claim 2 .

4. an environmental pressure of the mounting table when the first voltage is applied to the chuck electrode is 1.0 Torr or less; The substrate holding mechanism according to claim 1 .

5. a heater provided within the mounting table for heating the mounting table; a heater power supply that supplies power to the heater, The timing of supplying the second voltage to the chuck electrode is the heater causes the surface temperature of the mounting table to reach a predetermined substrate processing temperature. The substrate holding mechanism according to claim 1 .

6. The substrate processing temperature is 400°C or higher. The substrate holding mechanism according to claim 5 .

7. a heater provided within the mounting table for heating the mounting table; a heater power supply that supplies power to the heater, The timing of supplying the second voltage to the chuck electrode is The power supplied from the heater power supply to the heater is stabilized. The substrate holding mechanism according to claim 1 .

8. The control unit After the step of applying the first voltage and before the step of applying the second voltage, the chuck power supply is further configured to apply a third power, which is greater than the first voltage and less than the second voltage, to the chuck electrode after the workpiece substrate is placed on the substrate support surface. The substrate holding mechanism of claim 2 .

9. A substrate holding mechanism according to any one of claims 1 to 8, Substrate processing equipment.

10. A method for controlling a substrate holding mechanism including: a mounting table made of a dielectric material and having a substrate support surface for supporting a substrate to be processed; a chuck electrode provided in the mounting table for electrostatically attracting the substrate to be processed; a chuck power supply for applying a voltage to the chuck electrode; and a controller for controlling the chuck power supply, applying a first voltage from the chuck power supply to the chuck electrode before placing the substrate to be processed on the substrate support surface; placing the substrate to be processed on the substrate support surface; and applying a second voltage, which is different from the first voltage, to the chuck electrode from the chuck power supply after the substrate to be processed is placed on the substrate support surface. Control method.

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