Method for adjusting contact position of lift pin, method for detecting lift pin, and substrate placing mechanism

Abstract

The present application provides a lift pin contact position adjustment method, a lift pin contact position detection method, and a substrate placement mechanism that can automatically and with high precision adjust the contact position of a lift pin with respect to a substrate placed on a substrate placement table. The contact position adjustment method includes the steps of: placing a substrate on the substrate placement table; in a state in which the substrate is adsorbed by applying a voltage to an electrode of an electrostatic chuck; generating a torque waveform that indicates the time variation of the torque of a motor when moving the front end of the lift pin from a lower end position below the placement surface to an upper end position above the placement surface, for each of a plurality of voltages; calculating a contact time point that is the time at which the lift pin contacts the substrate, from the plurality of torque waveforms; calculating the contact position from the contact time point and the speed of the motor; determining whether the contact position is within an appropriate range; and automatically adjusting the contact position if it is determined that the contact position is outside the appropriate range.

Description

Technical Field

[0001] This invention relates to a method for adjusting the contact position of a lifting pin, a method for detecting the contact position of a lifting pin, and a substrate mounting mechanism. Background Technology

[0002] In a substrate processing apparatus that processes substrates such as semiconductor wafers, a substrate mounting stage on which the substrate is placed is provided with multiple lifting pins that can extend and retract relative to the substrate mounting surface to transfer the substrate to the substrate mounting stage.

[0003] Patent Document 1 describes a substrate processing apparatus that includes a substrate lifting device that uses a servo motor to lift a lifting pin to raise and lower the substrate. It also describes that a control unit monitors the output value of the motor driver from the servo motor, detects the height position of the lifting pin abutting against the lower surface of the substrate placed on the substrate mounting surface, and uses this height position to adjust the height of the lifting pin.

[0004] Existing technical documents

[0005] Patent documents

[0006] Patent Document 1: Japanese Patent Application Publication No. 2017-50534 Summary of the Invention

[0007] The technical problem that the invention aims to solve

[0008] This invention provides a technique for automatically and with high precision adjusting the contact position of the lifting pin relative to the substrate placed on the substrate stage.

[0009] Technical solutions for solving technical problems

[0010] One aspect of the present invention discloses a method for adjusting the contact position of a lifting pin, wherein, in a substrate mounting mechanism, the contact position is adjusted such that the height at which the front end of the lifting pin contacts the substrate is adjusted. The substrate mounting mechanism includes: a substrate mounting stage having an electrostatic chuck for electrostatically adsorbing the substrate and capable of holding the substrate; and a substrate lifting mechanism comprising the lifting pin, which is configured to extend and retract relative to the substrate mounting surface of the substrate mounting stage, and a drive mechanism having a motor for lifting the lifting pin. The method for adjusting the contact position of the lifting pin includes the following steps: placing the substrate on the substrate mounting stage, and adjusting the contact position of the electrostatic chuck... While the substrate is adsorbed by voltage applied to the electrodes of the suction cup, torque waveforms are generated for each voltage, representing the time-varying torque of the motor as the tip of the lifting pin moves from a lower position below the mounting surface to an upper position above the mounting surface. Based on the multiple torque waveforms, the contact time point at which the lifting pin contacts the substrate is determined, and the contact position is calculated based on the contact time point and the speed of the motor. It is then determined whether the contact position is within an appropriate range, and if it is determined that the contact position deviates from the appropriate range, the contact position is automatically adjusted.

[0011] Invention Effects

[0012] According to the present invention, a technique is provided that can automatically and with high precision adjust the contact position of the lifting pin relative to the substrate placed on the substrate stage. Attached Figure Description

[0013] Figure 1 This is a cross-sectional view of an example of a substrate processing apparatus having a substrate mounting mechanism capable of implementing a method for adjusting the contact position of a lifting pin according to one embodiment.

[0014] Figure 2 It is a cross-sectional diagram used to illustrate the lower, upper, and contact positions of the front end of the lifting pin.

[0015] Figure 3 This is a block diagram illustrating an example of the hardware structure of the control unit in a substrate processing apparatus according to one embodiment.

[0016] Figure 4 This is a functional block diagram representing the control section of the substrate mounting mechanism.

[0017] Figure 5 The diagrams are superimposed representations of the torque waveforms of the motor when the substrate is attracted by the voltage change applied to the electrodes of the electrostatic chuck in the substrate mounting mechanism. (a) is an overall view, and (b) is an enlarged view showing the area near the contact between the front end of the lifting pin and the substrate.

[0018] Figure 6 The graph shows the torque waveform of the motor when the lifting pin is made of Ti and Al2O3. (a) shows the case where a voltage of 1300V is applied and the substrate is adsorbed, and (b) shows the case where no voltage is applied.

[0019] Figure 7 This is a graph showing the relationship between voltage and torque at the contact point when the lifting pin is made of Ti and Al2O3, and the voltage applied to the electrodes of the electrostatic chuck changes multiple times to adsorb the substrate.

[0020] Figure 8 It is a cross-sectional diagram used to illustrate the elastic force of the bellows and the suction force of the electrostatic chuck at the contact point of the substrate mounting mechanism.

[0021] Figure 9 This is a schematic diagram illustrating the steps of a method for adjusting the contact position of a lifting pin according to one embodiment.

[0022] Figure 10 This is a flowchart illustrating a specific method for adjusting the contact position of a lifting pin according to one embodiment.

[0023] Figure 11 This diagram illustrates an example of determining the contact time by overlaying torque waveforms generated from multiple voltages, showing an example of bad tuning.

[0024] Figure 12 This diagram illustrates an example of determining the contact time by overlaying torque waveforms generated from multiple voltages, demonstrating an example of good tuning.

[0025] Figure 13 It is used for explanation Figure 11 A diagram illustrating the method for calculating the contact position under certain conditions.

[0026] Figure 14 It is used for explanation Figure 12 A diagram illustrating the method for calculating the contact position under certain conditions.

[0027] Explanation of reference numerals in the attached figures

[0028] 1: Substrate processing device

[0029] 10: Handling Containers

[0030] 12: Exhaust mechanism

[0031] 30: Sputtering Particle Release Section

[0032] 32: Target

[0033] 40: Substrate mounting stage

[0034] 46: Electrostatic chuck

[0035] 46a: Electrode

[0036] 48: DC power supply

[0037] 50: Substrate lifting mechanism

[0038] 51: Lifting pin

[0039] 54: Drive mechanism

[0040] 55: Motor

[0041] 57: Corrugated pipe

[0042] 60: Substrate mounting mechanism

[0043] 70: Control Department

[0044] 121: Substrate mounting mechanism control unit

[0045] 122: Voltage Control Unit

[0046] 124: Torque Waveform Generation Unit

[0047] 125: Contact Position Calculation Unit

[0048] 126: Judgment Department

[0049] 127: Contact position adjustment section

[0050] W: substrate. Detailed Implementation

[0051] Hereinafter, the embodiments will be described with reference to the accompanying drawings.

[0052] <Substrate Processing Device>

[0053] Figure 1 This is a cross-sectional view of an example of a substrate processing apparatus having a substrate mounting mechanism capable of implementing a method for adjusting the contact position of a lifting pin according to one embodiment.

[0054] In this embodiment, an example of a film-forming apparatus used to form a film on a substrate by sputtering will be described. Examples of substrates include semiconductor wafers, but the method is not limited to these.

[0055] like Figure 1 As shown, the substrate processing apparatus 1 includes a processing container 10, a sputtering particle release unit 30, a substrate mounting stage 40, a substrate lifting mechanism 50, and a control unit 70. The substrate mounting stage 40 and the substrate lifting mechanism 50 constitute a substrate mounting mechanism 60.

[0056] The processing container 10 houses the substrate W and maintains a vacuum inside. The upper side of the processing container is sloped. A gas inlet 11 is provided at the top of the processing container 10. A gas supply pipe (not shown) is connected to the gas inlet 11, supplying the gas required for sputtering film deposition (e.g., rare gases such as argon, krypton, and neon, or nitrogen). Furthermore, an exhaust mechanism 12 with a vacuum pump capable of reducing the pressure inside the processing container 10 to a vacuum is connected to the bottom of the processing container 10. Additionally, inlet and outlet ports 13 for feeding and discharging the substrate are formed on the side wall of the processing container 10. The inlet and outlet ports 13 are opened and closed by a gate valve 14. By opening the gate valve 14, communication is established with a vacuum transport chamber (not shown) adjacent to the processing container 10, and the substrate W is fed and discharged using a transport device (not shown) within the vacuum transport chamber.

[0057] The sputtering particle release unit 30 has multiple (two in the figure) target holders 31, multiple targets 32 held by each target holder 31, and multiple power sources 33 that apply voltage to each target holder 31.

[0058] The target holder 31 is made of a conductive material and is mounted on the upper inclined surface of the processing container 10 via an insulating component. The target holder 31 holds the target 32 ​​in such a way that the target 32 ​​is obliquely above the substrate W held by the substrate mounting mechanism 60 described later.

[0059] The target 32 ​​is made of a material containing the constituent elements of the film to be formed. For example, when forming a magnetic film (a film containing ferromagnetic materials such as Ni, Fe, and Co), the material used as the target 32 ​​can be, for example, CoFe, FeNi, or NiFeCo.

[0060] Multiple power supplies 33 are electrically connected to multiple target holders 31. By applying a voltage (e.g., DC voltage) to the target holders 31 from the power supplies 33, the sputtering gas dissociates around the target 32. Ions in the dissociated sputtering gas collide with the target 32, releasing sputtered particles, which are the constituent materials of the target 32, from the target 32.

[0061] Alternatively, there may be one target holder 31 and one target 32.

[0062] A substrate mounting stage 40 holds a substrate W, with its upper surface serving as the mounting surface. The substrate mounting stage 40 is formed as a plate with a diameter slightly larger than that of the substrate W, and includes a main body 41 made of a metallic material such as aluminum and an electrostatic chuck 46 disposed on the main body 41 for electrostatically adsorbing the substrate W. The upper surface of the electrostatic chuck 46 is the mounting surface, and electrodes 46a are embedded in a dielectric. By applying a DC voltage to the electrodes 46a from a DC power supply 48, the substrate W placed on the mounting surface is adsorbed using electrostatic force. The main body 41 is supported by a cylindrical support 47 extending downward from the center of its lower surface. The substrate mounting stage 40 is configured to be heated or cooled by a temperature control mechanism (not shown). In the case of a magnetic film (e.g., a film containing ferromagnetic materials such as Ni, Fe, and Co) used in a tunneling magnetoresistance (TMR) element, the substrate mounting stage 40 is cooled to an extremely low temperature below 100 K. In addition, the substrate stage 40 can also be rotated using a rotating mechanism (not shown).

[0063] The substrate lifting mechanism 50 includes: a plurality of lifting pins 51 for lifting the substrate; a support plate 52 for supporting the lifting pins; a lifting rod 53 for lifting the support plate 52; a drive mechanism 54; and a bellows 57.

[0064] Multiple lifting pins 51 are configured to insert into holes 44 formed in the substrate mounting stage 40, allowing them to extend and retract relative to the substrate mounting surface. The number and arrangement of the lifting pins 51 are appropriately determined based on the shape and size of the substrate W. Furthermore, the lifting pins 51 can be made of a conductive material such as Ti or an insulator such as Al2O3. A support plate 52 is configured to be positioned below the substrate mounting stage 40, supporting the multiple lifting pins 51 and moving them up and down together. One end of a lifting rod 53 is fixed to the lower surface of the support plate 52 and extends downwards, passing through an insertion hole 15 provided in the bottom wall of the processing container 10 to reach the outside of the processing container 10.

[0065] The drive mechanism 54 includes a motor 55 and a ball screw mechanism 56. The motor 55 rotates the ball screw (not shown) of the ball screw mechanism 56, causing the moving part 59, guided by the guided part (not shown), to move vertically. The lower end of the lifting rod 53 is mounted on the moving part 59. By rotating the motor 55, the lifting rod 53 is raised and lowered via the ball screw mechanism 56 and the moving part 59. Subsequently, multiple lifting pins 51 rise and fall together with the support plate 52. The motor 55 can be a servo motor or a stepper motor.

[0066] The front end of the lifting pin 51 is at Figure 2 The lower position shown in (a) is lower than the mounting surface and submerged in the hole 44 of the substrate mounting stage 40. Figure 2The substrate stage 40 shown in (b) moves between its upper position and its position above the mounting surface. Furthermore, Figure 2 The contact position is defined as the position where the front end of the lifting pin 51, as shown in (c), contacts the substrate W placed on the mounting surface of the substrate mounting stage 50. The origin of the front end of the lifting pin 51 is the lower position, and the contact position is defined as the height position relative to the origin, i.e., the lower position. Therefore, the contact position can be adjusted by adjusting the lower position, which serves as the origin.

[0067] The portion of the outer side of the bottom wall of the processing container 10 corresponding to the insertion hole 15 is shielded by a baffle plate 58 with a hole through which the lifting rod 53 is inserted. A bellows 57 is provided around the lifting rod 53 between the support plate 52 and the baffle plate 58. The bellows 57 shields the vacuum atmosphere inside the processing container 10 from the atmospheric atmosphere outside the processing container 10. In addition, the bellows 57 acts as an elastic element, and the elastic force acts upward on the lifting pin 51.

[0068] The torque of motor 55 is measured by a torque meter (not shown) and output as analog information (0-10V). The output value is processed by PLC 61 and sent to the control unit 70.

[0069] The control unit 70 controls various components of the substrate processing apparatus 1, such as the power supply 33, DC power supply 48, exhaust device 12, drive mechanism 54, etc. A portion of the control unit 70 also functions as the control unit of the substrate mounting mechanism 60. The control unit 70 is typically a computer. Figure 3 An example of the hardware structure of the control unit 70 is shown. The control unit 70 includes a main control unit 101, input devices 102 such as a keyboard and mouse, output devices 103 such as a printer, a display device 104, a storage device 105, an external interface 106, and a bus 107 connecting them to each other. The main control unit 101 has a CPU (Central Processing Unit) 111, RAM 112, and ROM 113. The storage device 105 records and retrieves information required for control. The storage device 105 has a computer-readable storage medium, which stores processing schemes for processing the substrate W, etc.

[0070] In the control unit 70, the CPU 111 uses the RAM 112 as its operating area to execute programs stored in the storage medium of the ROM 113 or storage device 105, thereby performing various operations such as substrate W processing. In this embodiment, it is particularly characterized by the detection and adjustment of the contact position of the lifting pin.

[0071] Figure 4This is a functional block diagram showing the substrate mounting mechanism control unit 121, which functions as part of the substrate mounting mechanism 60 within the control unit 70 and is used to adjust the contact position of the lifting pin. The substrate mounting mechanism control unit 121 includes a voltage control unit 122, a drive control unit 123, a torque waveform generation unit 124, a contact position calculation unit 125, a judgment unit 126, and a contact position adjustment unit 127.

[0072] The voltage control unit 122 controls the voltage of the DC power supply 48. The drive control unit 123 controls the drive mechanism 54 (motor 55) to drive the lifting pin 51. The torque waveform generation unit 124 has the function of generating waveforms (torque waveforms) for multiple voltages, representing the time change of the torque of the motor 55 when the front end of the lifting pin 51 is moved from the lower end position to the upper end position by the drive mechanism 54 in the state of adsorbing the substrate W. The contact position calculation unit 125 calculates the contact position of the lifting pin 51 based on the torque waveforms generated by the torque waveform generation unit 124 for multiple voltages. The judgment unit 126 judges whether the contact position of the lifting pin 51 calculated by the contact position calculation unit 125 is appropriate. If the judgment unit 126 judges that the contact position of the lifting pin 51 is inappropriate, the contact position adjustment unit 127 issues a command to the drive mechanism 54 of the lifting pin 51 to adjust the contact position to an appropriate range.

[0073] In the substrate processing apparatus 1 configured as described above, the gate 14 is opened, and the substrate W is fed into the processing container 10 using the conveying device (not shown) of the vacuum conveying chamber. At this time, the front end of the lifting pin 51 is located at the upper position extending upward from the mounting surface, and the substrate W held by the conveying device is transferred to the lifting pin 51. Then, by lowering the lifting pin 51, the substrate W is placed on the mounting surface of the substrate mounting stage 40, the conveying device is withdrawn from the processing container 10, and the gate 14 is closed. Then, by applying the desired adsorption voltage to the electrode 46a of the electrostatic chuck 46 from the DC power supply 48, the substrate W is electrostatically adsorbed.

[0074] Next, sputtering gas is introduced into the processing container 10 through the gas inlet 11, and the processing container 10 is controlled to a preset vacuum pressure using the exhaust mechanism 12 to perform sputtering film formation. Sputtering film formation is performed by applying voltage from the power supply 33 to the target holder 31, causing ions in the sputtering gas dissociated around the target 32 ​​to collide with the target 32. That is, by ion collision with the target 32, sputtered particles are released, and the sputtered particles are incident at an angle relative to the surface of the substrate W and deposited on the substrate W. At this time, by performing sputtering film formation while rotating the substrate stage 40 using the rotation mechanism, a more uniform film formation can be achieved.

[0075] After the film formation process is completed, sputtering gas is introduced into the processing container 10 through the gas inlet 11 as a purge gas to purge the processing container 10. Then, the adsorption voltage of the electrostatic chuck 46 is set to OFF, and after stripping and de-energizing (forced energization), the front end of the lifting pin 51 is raised from the lower position to the upper position to lift the substrate W. Afterward, the gate 14 is opened, and the substrate W on the lifting pin 51 is received by the conveying device of the vacuum conveying chamber and sent out of the processing container 10.

[0076] <Method for adjusting the contact position of the lifting pin>

[0077] The following describes the method for adjusting the contact position of the lifting pin in the substrate processing device described above.

[0078] Generally, in substrate loading stages equipped with electrostatic chucks, even if the electrostatic chuck's adsorption voltage is turned off during substrate delivery and a stripping charge is applied, there is a concern that abnormal charging may prevent the substrate from being detached from the chuck. If the lifting pin contacts the substrate without decelerating under such abnormal charging conditions, substrate breakage, displacement, or bouncing may occur. Therefore, the motor is controlled by reducing the Z-axis drive speed of the lifting pin at the contact position.

[0079] Furthermore, during sputtering film deposition as described in this embodiment using a substrate processing apparatus, the temperature of the substrate stage ranges from an extremely low temperature of 100K (-173°C) to a high temperature of around 400°C. Due to the expansion and contraction of the lifting pins, the contact position changes. In addition, the contact position can also change due to mechanical errors in the apparatus or errors during maintenance. Therefore, when changing the temperature of the substrate stage, using a height measuring tool, etc., it is necessary to check whether the contact position is appropriate and to adjust it if it is not.

[0080] However, such instruction is conducted under atmospheric and room temperature conditions. Therefore, especially under extremely low and high temperature conditions, it is necessary to predict the expansion and contraction of the lifting pins, without knowing the precise contact position. Consequently, it is impossible to effectively prevent the lifting pins from contacting the substrate without decelerating at the contact position, and the possibility of substrate breakage, displacement, and bouncing still exists.

[0081] Furthermore, in Patent Document 1, a control unit monitors the output value of the motor driver from the servo motor (the difference between the command pulse and the feedback pulse in the servo motor, i.e., the retained pulse, or the torque value in the servo motor). Moreover, the height position of the lifting pin at which its tip abuts against the lower surface of the substrate placed on the substrate mounting surface is detected, and this height position is used to adjust the height of the lifting pin. However, in the technology of cited Document 1, due to differences in the method of setting the threshold and the strength of the electrostatic chuck's adhesion to the substrate, the contact position of the lifting pin may shift, resulting in insufficient detection accuracy of the lifting pin's contact position.

[0082] Therefore, in this embodiment, the contact position of the lifting pin is detected using a torque waveform that represents the time-varying torque of the motor 55 as the front end of the lifting pin 51 moves from the lower position to the upper position while the substrate W is adsorbed. Specifically, the substrate W is adsorbed by varying the voltage applied to the electrode 46a of the electrostatic chuck 46, and a torque waveform is obtained for each voltage. The contact position is then calculated (detected) based on these waveforms.

[0083] Figure 5 This diagram shows the overlapping torque waveforms of the motor 55 when the voltage applied to the electrode 46a of the electrostatic chuck 46 varies and the substrate W is adsorbed in the substrate mounting mechanism 60. (a) is an overall view, and (b) is an enlarged view showing the area near the substrate where the tip of the lifting pin contacts the substrate. Here, torque waveforms are shown when the substrate W is mounted on the substrate mounting stage 40 and the electrode 46a of the electrostatic chuck 46 is subjected to 400V, 600V, 800V, 1000V, and 1300V. Furthermore, Figure 5 The feedback speed of motor 55 is also shown.

[0084] like Figure 5 As shown in (a), due to the elastic force of the bellows 57, the torque value decreases overall as the front end of the lifting pin 51 moves from the lower position to the upper position. Furthermore, as... Figure 5 As shown in (b), up to the middle, the torque waveform is approximately the same for all voltages, but from the moment the lifting pin 51 contacts the substrate W (contact point), the torque waveform separates according to the voltage. Furthermore, vibrations corresponding to the visible bouncing of the substrate W appear in the torque waveform. Therefore, it can be seen that, based on the voltage applied to electrode 46a, the charging voltage (adsorption voltage) when abnormal charging occurs in the actual device can be monitored.

[0085] Figure 6This is a graph showing the torque waveform of motor 55 when the lifting pin 51 is made of Ti and Al2O3. (a) shows the case where a voltage of 1300V is applied and the substrate W is attracted, and (b) shows the case where no voltage is applied. As shown in the graph, for both Ti and Al2O3: in case (a) where a voltage is applied, the torque decreases significantly at the contact time point, and the torque continues to decrease, but at a certain moment the torque changes drastically. Similarly, for both Ti and Al2O3: in case (b) where no voltage is applied, no significant decrease in torque is observed, nor is there a drastic change in torque.

[0086] This indicates that when voltage is applied to electrode 46a, the substrate W temporarily adheres to the electrostatic chuck 46 after contact with the lifting pin 51. At a certain moment, the adhesion is abruptly released, resulting in a "bouncing." Without applied voltage, no such adhesion or "bouncing" of the substrate W was observed. In other words, regardless of the material of the lifting pin, the attraction force on the substrate W generated by applying voltage to electrode 46a of the electrostatic chuck 46 results in a significant decrease in torque after the contact point, and a "bouncing" occurs at the moment the attraction force is released.

[0087] Figure 7 This graph shows the relationship between voltage and torque at contact points when the lifting pin 51 is made of Ti and Al2O3, and the voltage applied to the electrode 46a of the electrostatic chuck 46 varies with different voltage levels to attract the substrate W. As shown in the graph, regardless of the material of the lifting pin, there is a tendency for the torque to decrease as the voltage increases. This is because, as... Figure 8 As shown, when the voltage of electrode 46a, i.e., the charged voltage, increases, the downward force, i.e., the adsorption force, increases relative to the upward force, i.e., the elastic force of the bellows 57. Furthermore, in Figure 7 In the process, when the lifting pin 51 is made of Ti, the torque is greater than when it is made of Al2O3, and this tendency is particularly strong at a maximum voltage of 2000V. It is speculated that the reason is that by using Ti as a conductor, the lifting pin 51 can achieve a static elimination effect, the adsorption force is weakened, and the upward pushing force due to the elastic force of the bellows 57 is strengthened.

[0088] As can be seen from the above, the reason for the separation of torque waveforms at the contact time point is that when the lifting pin 51 contacts the substrate W, the applied voltage increases, resulting in a greater adsorption force and a lower torque of the motor 55. Thus, at the contact time point where the lifting pin 51 contacts the substrate W, the adsorption force changes according to the voltage, leading to torque separation. Therefore, the contact time point can be accurately detected in actual equipment.

[0089] Based on the contact time and the feedback speed of the motor 55, the contact position of the front end of the lifting pin 51, defined with the lower end position as the origin, can be detected (calculated).

[0090] The steps of the lifting pin contact position adjustment method of this embodiment will be briefly described below. Figure 9 This is a schematic diagram illustrating the steps of the method for adjusting the contact position of the lifting pin according to this embodiment.

[0091] like Figure 9 As shown, firstly, a substrate W is placed on a substrate mounting stage 40, and multiple voltages are used to generate torque waveforms when the front end of the lifting pin moves from the lower end position to the upper end position while the substrate W is attracted by the electrode 46a of the electrostatic chuck 46 (step S1).

[0092] In step S1, in the torque waveform generation unit 124, a waveform of the time change of the torque of the motor 55 when the front end of the lifting pin moves from the lower end position to the upper end position under each voltage is generated, namely the torque waveform.

[0093] Next, the contact time points are obtained by superimposing the torque waveforms generated by multiple voltages, and the contact position of the lifting pin 51 is calculated based on the contact time points and the feedback speed of the motor 55 (step S2).

[0094] In step S2, the contact position calculation unit 125 makes a calculation as follows: Figure 5 The diagram shown is an overlay of the torque waveforms generated for each voltage to determine the moment when the torques separate as the contact time point. The contact position is calculated based on the contact time point and the feedback speed of the motor 55 associated with the position of the lifting pin 51.

[0095] Next, it is determined whether the calculated contact position is within an appropriate range (step S3). This determination is made by the determination unit 126.

[0096] Next, if it is determined that the contact position deviates from the appropriate range, the contact position is automatically adjusted (step S4). The automatic adjustment of the contact position is performed by controlling the drive mechanism 54 to adjust the lower end position of the front end of the lifting pin 51 according to the instruction from the contact position adjustment unit 127.

[0097] Through the above steps S1 to S4, the contact position of the lifting pin 51 can be automatically and with high precision. Even under conditions of significant thermal expansion of the lifting pin 51, such as in cryogenic or high-temperature treatments, the cracking, displacement, and bouncing of the substrate can be effectively prevented. Furthermore, because the contact position can be automatically and with high precision adjusted in this way, mechanical errors of the device can also be reduced.

[0098] The method for adjusting the contact position of the lifting pin in this embodiment will now be described in more detail. Figure 10 This is a flowchart illustrating the specific method for adjusting the contact position of the lifting pin in this embodiment.

[0099] First, the front end of the lifting pin 51 is positioned at the lower end (step S11), and a voltage is applied to the electrode 46a of the electrostatic chuck 46 (step S12). This chucks the substrate W. At this time, one of a set voltage is applied. In this example, 400V, 600V, 800V, 1000V, and 1300V are set, and 400V is applied first. The voltage is not limited to these values. The number of voltages set is also not limited, but preferably three or more.

[0100] Next, the torque measurement of motor 55 is started (step S13), and the front end of lifting pin 51 is raised to the upper position (step S14). Then, the torque measurement is ended (step S15), a torque waveform is generated (step S16), and the voltage of electrostatic chuck 46 is turned off (step S17). The generation of the torque waveform is performed by torque waveform generation unit 124 of control unit 70.

[0101] Return the front end of the lifting pin 51 to the lower position (step S18), apply other voltages to the electrodes 46a of the electrostatic chuck 46, and similarly perform torque measurement and torque waveform generation (steps S13-S18). Perform the above actions for all voltages (step S19). The above series of actions is equivalent to... Figure 9 Step S1.

[0102] Next, the contact position is calculated based on the torque waveform of each voltage (step S20). Step S20 corresponds to... Figure 9 Step S2. Here, firstly, as described above, the contact time point is determined by overlaying the torque waveforms generated by multiple voltages respectively. Figure 11 and Figure 12 This diagram illustrates an example of determining the contact time by overlaying torque waveforms generated from multiple voltages. Figure 11 In the example where the lifting pin 51 contacts the substrate W before the motor 55 decelerates, this is an example of bad tuning. On the other hand, in Figure 12 In the example, after the motor 55 decelerates, the lifting pin 51 contacts the substrate, which is an example of good tuning.

[0103] The calculation of the contact position after determining the contact time point is as described above, based on the contact time point and the feedback speed of motor 55, with reference to... Figure 11 and Figure 12 Corresponding to Figure 13 and Figure 14 The calculation method is explained in detail. Furthermore, in Figure 13 and Figure 14For convenience, the torque waveforms are only depicted when the voltage is 400V, 800V, and 1300V.

[0104] Figure 13 (a) is with Figure 11 Similarly, the graph with the torque waveform superimposed is enlarged and also shows the distance the lifting pin 51 moves from the origin, calculated based on the feedback speed of the motor 55. As shown in (b), the distance moved at the contact time point is 1.43 mm, and the contact position is 1.43 mm.

[0105] Figure 14 (a) is with Figure 12 Similarly, the graph with the torque waveform superimposed is enlarged and also shows the distance the lifting pin 51 moves from the origin, calculated based on the feedback speed of the motor 55. As shown in (b), the distance moved at the contact time point is 1.95 mm, and the contact position is 1.95 mm.

[0106] Next, it is determined whether the contact position is within the range of 1.95 to 2.00 mm (step S21). As described above, the contact between the lifting pin 51 and the substrate W is preferably within... Figure 13 (a) and Figure 14 The motor deceleration of the lifting pin 51 shown in (a) A is carried out in the region. Here, an example is shown in which the contact position is in the range of 1.95 to 2.00 mm in order to make the contact time point enter a specific range within region A. However, it is not limited to this range.

[0107] If the contact position is within the range of 1.95 to 2.00 mm in step S21, no adjustment is required, and the process can be terminated directly. Figure 14 During the adjustment, the contact position was 1.95mm, so the process was terminated directly.

[0108] If the deviation is between 1.95 and 2.00 mm, determine whether it is below 1.95 mm or above 2.00 mm (step S22). If it is below 1.95 mm, adjust the origin by subtracting the insufficient portion ΔX (step S23). That is, shift the origin downwards by ΔX, making the contact position ΔX longer relative to the origin. Figure 13 When the contact position is 1.43 mm, ΔX is set to 0.57 mm, and the origin is adjusted so that the contact position is 2.00 mm from the origin. On the other hand, when the contact position exceeds 2.00 mm, the origin is adjusted by adding ΔX as the excess amount (step S24). That is, the origin is shifted upward by ΔX, and the contact position is shortened by ΔX relative to the origin.

[0109] Therefore, the contact position of the lifting pin 51 can be adjusted automatically and with high precision.

[0110] <Other Applications>

[0111] The embodiments have been described above, but it should be considered that the embodiments disclosed herein are illustrative rather than restrictive in all respects. The above embodiments may be omitted, substituted, or modified in various ways without departing from the claims and their spirit.

[0112] For example, in the above embodiment, sputtering film formation was used as an example of substrate processing, but it is not limited to this. Other processing methods such as CVD film formation and etching can also be used.

Claims

1. A method for adjusting the contact position of a lifting pin, characterized in that: In the substrate placement mechanism, the contact position of the lifting pin at its front end is adjusted to ensure a certain height. The substrate placement mechanism includes: a substrate placement stage having an electrostatic chuck for electrostatically adsorbing the substrate; and a substrate lifting mechanism comprising the lifting pin, which is configured to extend and retract relative to the substrate placement surface of the substrate placement stage, and a drive mechanism having a motor for raising and lowering the lifting pin. The method for adjusting the contact position of the lifting pin includes the following steps: With a substrate placed on the substrate mounting platform and the substrate being attracted by a voltage applied to the electrodes of the electrostatic chuck, torque waveforms representing the time-varying torque of the motor are generated for each of the multiple voltages as the front end of the lifting pin moves from a lower position below the mounting surface to an upper position above the mounting surface. Based on multiple torque waveforms, the contact time point at which the lifting pin contacts the substrate is determined, and the contact position is calculated based on this contact time point and the speed of the motor. Determine whether the contact position is within an appropriate range; and If the contact position is determined to be off-range, the contact position will be automatically adjusted. When calculating the contact position, the contact time point is obtained by overlaying the torque waveforms generated by the multiple voltages respectively. The contact time point is the moment when the torque waveforms corresponding to the plurality of voltages separate.

2. The method for adjusting the contact position of the lifting pin according to claim 1, characterized in that: The substrate mounting mechanism has an elastic component that applies an upward elastic force to the lifting pin.

3. The method for adjusting the contact position of the lifting pin according to claim 1 or 2, characterized in that: The contact position is defined as a height position with the lower end position as the origin, and the automatic adjustment of the contact position is performed by adjusting the lower end position by controlling the drive mechanism.

4. A method for detecting the contact position of a lifting pin, characterized in that: In a substrate placement mechanism, a detection position is detected where the front end of a lifting pin contacts the substrate. The substrate placement mechanism includes: a substrate placement stage having an electrostatic chuck for electrostatically adsorbing the substrate; and a substrate lifting mechanism comprising the lifting pin, which is configured to extend and retract relative to the substrate placement surface of the substrate placement stage, and a lifting section having a motor for raising and lowering the lifting pin. The method for detecting the contact position of the lifting pin includes the following steps: With a substrate placed on the substrate mounting platform and the substrate attracted by a voltage applied to the electrodes of the electrostatic chuck, torque waveforms representing the time-varying torque of the motor are generated for each of the multiple voltages, indicating the movement of the tip of the lifting pin from a lower position below the mounting surface to an upper position above the mounting surface; and Based on multiple torque waveforms, the contact time point, which is the moment when the lifting pin contacts the substrate, is determined. Based on this contact time point and the speed of the motor, the contact position is calculated. When calculating the contact position, the contact time point is determined by overlaying the torque waveforms generated by the multiple voltages respectively. The contact time point is the moment when the torque waveforms corresponding to the plurality of voltages separate.

5. The method for detecting the contact position of the lifting pin according to claim 4, characterized in that: The substrate mounting mechanism has an elastic component that applies an upward elastic force to the lifting pin.

6. A substrate placement mechanism that places a substrate within a processing container of a substrate processing apparatus for processing a substrate, the substrate placement mechanism being characterized by comprising: A substrate stage, which has an electrostatic chuck for electrostatic adsorption of substrates, is capable of placing substrates. A substrate lifting mechanism includes a lifting pin that is configured to extend and retract relative to the substrate mounting surface of the substrate mounting stage, and a drive mechanism having a motor for lifting the lifting pin. as well as Control Department The control unit includes: The torque waveform generation unit generates torque waveforms for multiple voltages when the substrate is placed on the substrate mounting platform and the substrate is attracted by the electrode of the electrostatic chuck. These waveforms represent the time change of the motor torque when the front end of the lifting pin moves from a lower position below the mounting surface to an upper position above the mounting surface using the drive mechanism. The contact position calculation unit determines the moment when the lifting pin contacts the substrate, i.e., the contact time point, based on multiple torque waveforms. Based on this contact time point and the speed of the motor, it calculates the contact position as the height position of the front end of the lifting pin when it contacts the substrate. The determination unit determines whether the contact position is within an appropriate range; and The contact position adjustment unit automatically adjusts the contact position when it determines that the contact position deviates from the appropriate range. When calculating the contact position, the contact position calculation unit superimposes the torque waveforms generated by the multiple voltages to determine the contact time point. The contact position calculation unit uses the time points at which the torque waveforms corresponding to the plurality of voltages separate as the contact time points.

7. The substrate mounting mechanism according to claim 6, characterized in that: It also includes an elastic component that applies an upward elastic force to the lifting pin.

8. The substrate mounting mechanism according to claim 6 or 7, characterized in that: The contact position is defined as the height position with the lower end position as the origin, and the contact position adjustment unit controls the drive mechanism to adjust the lower end position.

9. The substrate mounting mechanism according to claim 6 or 7, characterized in that: The substrate processing apparatus is a sputtering apparatus that deposits sputtered particles from a target onto the substrate to form a film.

Images