Apparatus for detecting position of wafer and method of operating same

Abstract

An apparatus for detecting a position of a wafer includes a plurality of lift pins for disposing the wafer on a support bracket, and a plurality of piezoelectric resonators at lower portions of the plurality of lift pins, respectively, at least one first piezoelectric resonator of the plurality of piezoelectric resonators is configured to vibrate a corresponding lift pin of the plurality of lift pins, and at least one second piezoelectric resonator of the plurality of piezoelectric resonators is configured to detect a resonant frequency of a combined structure including the wafer and the plurality of lift pins, the resonant frequency corresponds to the vibration, and the apparatus further includes a controller configured to determine a position of the wafer as a function of a change in the resonant frequency.

Description

[0001] Cross - reference to related applications

[0002] This application claims the benefit of priority to Korean Patent Application No. 10 - 2024 - 0006405, filed on January 16, 2024, and Korean Patent Application No. 10 - 2024 - 0054906, filed on April 24, 2024, with the Korean Intellectual Property Office, the disclosures of which are incorporated herein by reference in their entireties. Technical field

[0003] Aspects of the present inventive concept relate to an apparatus for detecting the position of a wafer and an operating method thereof. Background art

[0004] Generally, in semiconductor processes, the importance of technologies capable of detecting the real - time position of wafers is increasing to control process variables and prevent problems such as wafer slip or breakage. Due to various environmental limitations, there is currently no effective method for measuring the position of wafers. These environmental limitations include the narrow physical space for displacement sensors, process shocks when the sensors are exposed to the process, and performance degradation in high - temperature and plasma environments. As an alternative, one method involves using an automatic wafer centering sensor (AWC) to indirectly predict the wafer position by comparing the positions when the wafer enters and exits the chamber. However, this method does not allow real - time position monitoring, making it difficult to prevent problems related to the wafer position in advance. In addition, in a structure such as a four - type chamber composed of multiple stations, it is impossible to accurately measure position changes using only the AWC. Summary of the invention

[0005] An aspect of the present inventive concept provides an apparatus for detecting the position of a wafer in a processing chamber and an operating method thereof, which are capable of detecting the position of the wafer in real time.

[0006] According to an aspect of the present inventive concept, an apparatus for detecting the position of a wafer includes: a plurality of lift pins configured to place a wafer on a support bracket; and a plurality of piezoelectric resonators respectively disposed below the plurality of lift pins, wherein at least one first piezoelectric resonator among the plurality of piezoelectric resonators is configured to vibrate a corresponding lift pin among the plurality of lift pins, wherein at least one second piezoelectric resonator among the plurality of piezoelectric resonators is configured to detect a resonance frequency of a combined structure including the wafer and the plurality of lift pins, the resonance frequency corresponding to the vibration, and wherein the apparatus further includes a controller configured to determine the position of the wafer based on a change in the resonance frequency.

[0007] According to an aspect of the inventive concept, an apparatus for detecting a position of a wafer includes: a plurality of piezoelectric resonators; and a controller configured to receive an electrical signal from at least one of the plurality of piezoelectric resonators and determine a position of the wafer based on the received electrical signal, the electrical signal corresponding to a resonance frequency of a combined structure including the wafer and a plurality of lift pins.

[0008] According to an aspect of the inventive concept, an apparatus for detecting a position of a wafer includes: lift pins configured to vertically move in holes of a support bracket to place the wafer on the support bracket; a connection assembly connected to a lower portion of the lift pins; a piezoelectric resonator located at a lower portion of the connection assembly, the piezoelectric resonator configured to detect a resonance frequency of the lift pins; an actuator configured to vertically move the lift pins; and a controller configured to control the actuator, wherein the controller is configured to receive an electrical signal corresponding to the resonance frequency from the piezoelectric resonator and determine a position of the wafer based on the electrical signal.

[0009] According to an aspect of the inventive concept, a method of operating an apparatus for detecting a position of a wafer includes: setting the wafer on a support bracket via lift pins; detecting a resonance frequency of a wafer-lift pin structure using a piezoelectric resonator; and measuring a position of the wafer using the detected resonance frequency. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] The above and other aspects, features, and advantages of the inventive concept will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, in which:

[0011] Figure 1 is a diagram illustrating a substrate processing system according to an exemplary embodiment of the inventive concept;

[0012] Figure 2 is a diagram illustrating a semiconductor manufacturing apparatus according to an exemplary embodiment of the inventive concept;

[0013] Figure 3 is a diagram illustrating a semiconductor manufacturing apparatus performing a normal automatic wafer centering function;

[0014] Figure 4 is a diagram illustrating an apparatus for detecting a position of a wafer according to an exemplary embodiment of the inventive concept;

[0015] Figure 5A and Figure 5B is a diagram illustrating a deviation of a wafer position in an apparatus for detecting a position of a wafer according to an exemplary embodiment of the inventive concept;

[0016] Figure 6A 、 Figure 6B and Figure 6Cis a diagram showing the prediction of the position of a wafer by measuring a resonance frequency in an apparatus for detecting the position of a wafer according to an exemplary embodiment of the inventive concept;

[0017] Figure 7A and Figure 7B is a diagram showing the measurement result of the resonance frequency according to the position of a wafer in an apparatus for detecting the position of a wafer according to an exemplary embodiment of the inventive concept;

[0018] Figure 8 is a diagram showing the resonance frequency according to the degree of deviation of a wafer from the center in an apparatus for detecting the position of a wafer according to an exemplary embodiment of the inventive concept;

[0019] Figure 9A 、 Figure 9B and Figure 9C is a diagram showing a lift pin assembly according to an exemplary embodiment of the inventive concept;

[0020] Figure 10A and Figure 10B is a diagram showing an apparatus for detecting the position of a wafer; and

[0021] Figure 11 is a flowchart showing a wafer position detection operation of a semiconductor manufacturing apparatus according to an exemplary embodiment of the inventive concept. DETAILED DESCRIPTION

[0022] Hereinafter, exemplary embodiments of the inventive concept will be described with reference to the accompanying drawings.

[0023] A wafer position detection apparatus and an operation method thereof according to an embodiment of the present invention can detect the position of a wafer placed on a lift pin inside a chamber in real time by using a piezoelectric resonator. The wafer position detection apparatus of the present invention can measure the position of a wafer on a lift pin in real time. Since the sensor of the wafer position detection apparatus of the present invention is attached outside the processing space (e.g., below the lift pin), it does not affect the processing. The wafer position detection apparatus of the present invention can accurately measure the position of a wafer (expected sensitivity: about 0.5 mm / Hz). The wafer position detection apparatus of the present invention can accurately measure the position of a wafer inside the chamber in real time.

[0024] Figure 1 is a diagram showing a substrate processing system 1 according to an exemplary embodiment of the inventive concept. Referring to Figure 1 , the substrate processing system 1 may include a facility front end module 10 and a processing facility 20. The facility front end module 10 may be installed in the front of the processing facility 20. The facility front end module 10 may transfer a substrate between a container 16 containing a substrate and the processing facility 20. The facility front end module 10 may include a plurality of load ports 12 and a frame 14. The frame 14 may be disposed between the load port 12 and the processing facility 20.

[0025] A container 16 for accommodating a substrate can be mounted on a load port 12 by a transfer unit such as an overhead conveyor, an overhead transporter, or an automated guided vehicle. The container 16 can be an airtight container, such as a front-open unified pod. A frame robot 18 for transferring the substrate between the container 16 disposed in the load port 12 and the processing facility 20 can be disposed within a frame 14. An opener for automatically opening and closing a door of the container 16 can be mounted within the frame 14. Additionally, the frame 14 can include a fan filter unit that supplies clean air to the frame 14 such that the clean air flows from the top to the bottom within the frame 14.

[0026] The processing facility 20 can include a load lock chamber 22, a transfer chamber 24, and a processing chamber 28. The transfer chamber 24 has a substantially polygon shape when viewed from above. The load lock chamber 22 and / or the processing chamber 28 can be disposed at a side of the transfer chamber 24.

[0027] The load lock chamber 22 can be interposed between the transfer chamber 24 and the facility front end module 10. At least one load lock chamber 22 can be provided. According to an example, two load lock chambers 22 can be provided. Among the two load lock chambers 22, the substrate introduced into the processing facility 20 can be accommodated in a first load lock chamber 22a. Among the two load lock chambers 22, the substrate that has completed processing and is unloaded from the processing facility 20 can be accommodated in a second load lock chamber 22b. Alternatively, one or more load lock chambers 22 can be provided, and substrates can be loaded into or unloaded from each load lock chamber 22.

[0028] A transfer robot 26 can be mounted within the transfer chamber 24. The transfer robot 26 can load a substrate S (see Figure 2 ) into the processing chamber 28, or unload the substrate S from the processing chamber 28. Additionally, the transfer robot 26 can transfer the substrate S between the processing chamber 28 and the load lock chamber 22.

[0029] The interiors of the transfer chamber 24 and the processing chamber 28 can be maintained in a vacuum, and the interior of the load lock chamber 22 can be switched between a vacuum and atmospheric pressure. The load lock chamber 22 can prevent external contaminants from entering the transfer chamber 24 and the processing chamber 28. Gate valves can be mounted between the load lock chamber 22 and the transfer chamber 24 and between the load lock chamber 22 and the facility front end module 10. The gate valves can be opened and closed between the load lock chamber 22 and the transfer chamber 24 and between the load lock chamber 22 and the facility front end module 10. For example, when the substrate moves between the facility front end module 10 and the load lock chamber 22, the gate valve disposed between the load lock chamber 22 and the transfer chamber 24 can be closed. Additionally, when the substrate moves between the load lock chamber 22 and the transfer chamber 24, the gate valve disposed between the load lock chamber 22 and the facility front end module 10 can be closed.

[0030] The processing chamber 28 can be implemented to perform a predetermined process on a substrate. For example, the processing chamber 28 can perform processes such as a deposition process, a developing process, a cleaning process, or a curing process. One or more processing chambers 28 can be disposed along a side of the transfer chamber 24. When multiple processing chambers 28 are provided, each processing chamber 28 can perform the same process on the substrate, or can perform different processes on the substrate from each other.

[0031] In addition, the processing chamber 28 can include a device for detecting the position of the wafer in real time while performing the process. The device for detecting the position of the wafer can detect the position of the wafer by measuring the resonance frequency corresponding to the substrate using a piezoelectric resonator and comparing the measured resonance frequency with the initial resonance frequency.

[0032] Figure 2 is a diagram showing a semiconductor manufacturing apparatus 200 according to an exemplary embodiment of the inventive concept. Referring to Figure 2 , the semiconductor manufacturing apparatus 200 can include a chamber 201, a support device 210, a gas supply unit 222, a controller 220, a light source unit 230, and a lift pin assembly 270. Here, the semiconductor manufacturing apparatus 200 can perform a curing process on a photoresist pattern PRP coated on a substrate S. In the exemplary embodiment, the process performed using the semiconductor manufacturing apparatus 200 can be a curing process.

[0033] The chamber 201 can have a cylindrical shape with an internal space where a process is performed. The chamber 201 can be configured to isolate the space where the process is performed from the outside. In addition, an exhaust pipe 206 for discharging by-products generated during the process can be connected to an outer surface of the chamber 201. The exhaust pipe 206 can include a pump for maintaining the inside of the chamber 201 at a processing pressure during the process, and a valve for opening and closing a passage in the exhaust pipe. The chamber 201 can include a transparent separator 282 disposed between the substrate S and the light source unit 230.

[0034] The transparent separator 282 can separate the chamber 201 into a first space 202 and a second space 203. The transparent separator 282 can allow light emitted from the light source unit 230 to pass through. That is, the transparent separator 282 can be formed of a transparent material that allows light to pass through. For example, the transparent separator 282 can be formed of a quartz material, but is not limited thereto. The first space 202 can be an upper space inside the chamber 201, and can be a space including the light source unit 230. The second space 203 can be a lower space inside the chamber 201, and can be a space including the substrate S. The second space 203 can be a vacuum space. In addition, in a subsequent process, a reaction gas can be introduced into the second space 203.

[0035] The support device 210 has a support plate 212 that supports the substrate S during processing. The support device 210 is generally disk-shaped. A support shaft 211 that is rotatable by a driver 276 is fixedly coupled to the lower surface of the support plate 212. During processing, the substrate S can rotate. The support device 210 can fix the substrate S using methods such as electrostatic force or mechanical clamping. The substrate S can be fixed to the support plate 212 by electrostatic force generated by a voltage supplied from a voltage supplier 290.

[0036] The gas supply unit 222 can supply gas into the chamber 201. The gas supply unit 222 can supply gas into the chamber 201 through a gas supply pipe 224. Specifically, the gas supply unit 222 can supply gas into the first space 202. Here, the supplied gas can be an inert gas. The inert gas can cool the first space 202. A valve that opens and closes the internal passage can be installed in the gas supply pipe 224.

[0037] The controller 220 can adjust the amount and radiation time of the light emitted from the light source unit 230. Additionally, the controller 220 can receive the heating temperature of the substrate from a temperature controller. For example, the controller 220 can detect the light emitted from the light source unit 230 through a window 294. The controller 220 can receive the temperature of the first space 202 from a temperature sensor 292. When the temperature of the first space 202 exceeds a preset reference temperature, the controller 220 can control the gas supply unit 222 to supply gas into the first space 202.

[0038] Although not shown, the controller can include one or more of the following components: at least one central processing unit (CPU) configured to execute computer program instructions to perform various processes and methods; a random access memory (RAM) and a read-only memory (ROM) configured to access and store data and information as well as computer program instructions; an input / output (I / O) device (e.g., keyboard, mouse, display, speaker, printer, modem, network card, etc.) configured to provide input and / or output to the controller 220; and a storage medium or other suitable type of memory (e.g., such as by way of example RAM, ROM, programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), magnetic disk, optical disk, floppy disk, hard disk, removable cartridge tape, flash drive, any type of tangible and non-transitory storage medium) that can store data and / or instructions. Additionally, the controller can include an antenna, a network interface that provides a wireless and / or wired digital and / or analog interface to one or more networks through one or more network connections (not shown), a power supply that provides appropriate alternating current (AC) or direct current (DC) to power one or more components of the controller, and a bus that allows communication between the various disclosed components of the controller.

[0039] The light source unit 230 may irradiate light onto the substrate S coated with the photoresist pattern PRP. The light source unit 230 may cure the photoresist pattern PRP by irradiating light. The light source unit 230 may irradiate UV light. The light source unit 230 may include a plurality of lamps. The light source unit 230 may include any one of a halogen lamp, a mercury lamp, a xenon lamp, and an LED lamp.

[0040] In an exemplary embodiment, the wavelength of the light emitted by the light source unit 230 may be in the range of 200 nm to 800 nm. In an exemplary embodiment, the wavelength of the light emitted by the light source unit 230 may be in the range of 300 nm to 700 nm.

[0041] The lift pin assembly 270 loads the substrate onto the support plate 212 or unloads the substrate from the support plate 212. The lift pin assembly 270 has lift pins 272, a lift pin support plate 274, and a driver 276. The lift pins 272 are fixedly mounted on the lift pin support plate 274 and move together with the lift pin support plate 274. The lift pin support plate 274 has a disk shape and is located below the support plate 212 in the chamber 201 or outside the chamber 201. The lift pin support plate 274 moves up and down by a driver 276 such as a hydraulic cylinder, a pneumatic cylinder, or a motor.

[0042] In addition, the lift pin assembly 270 may include at least one piezoelectric resonator that generates a vibration signal or detects a vibration signal.

[0043] The semiconductor manufacturing apparatus 200 may detect the position of the wafer in real time by detecting the resonance frequency using the piezoelectric resonator.

[0044] Figure 3 FIG. is a diagram showing a semiconductor manufacturing apparatus 30 that performs a normal automatic wafer centering function. The general semiconductor manufacturing apparatus 30 may predict the position of the wafer or the change amount of the wafer in the chamber by comparing the in / out positions of the wafer through an automatic wafer centering (AWC) function.

[0045] The wafer position may be measured by comparing the in / out coordinates after the process is completed. However, the conventional device for detecting the position of the wafer cannot measure the wafer position in real time. In addition, in the quad-chamber where the wafer moves inside the chamber, it is impossible to detect the wafer position.

[0046] Figure 4 FIG. is a diagram showing a device 40 for detecting the position of a wafer according to an exemplary embodiment of the inventive concept. Referring to Figure 4 , the device 40 for detecting the position of the wafer includes a plurality of lift pins 41-1, 41-2, and 41-3 and a plurality of piezoelectric resonators 42-1, 42-2, and 42-3.

[0047] A plurality of lift pins 41-1, 41-2, and 41-3 can be implemented to set the wafer W on the support bracket. Each of the plurality of piezoelectric resonators 42-1, 42-2, and 42-3 can be disposed below the corresponding lift pins 41-1, 41-2, and 41-3 and can be disposed in the connecting portions of the lift pins 41-1, 41-2, and 41-3. For example, each of the lift pins 41-1, 41-2, and 41-3 can be disposed between the wafer and the corresponding piezoelectric resonators 42-1, 42-2, and 42-3. Each of the plurality of piezoelectric resonators 42-1, 42-2, and 42-3 can be implemented to generate vibrations by using the piezoelectric effect in each of the lift pins 41-1, 41-2, and 41-3. The piezoelectric effect refers to the phenomenon of generating an electrical signal by changing the internal charge distribution of a crystal through a constant pressure or displacement. By utilizing this effect, the piezoelectric resonator can convert mechanical energy into electrical energy. In addition, each of the plurality of piezoelectric resonators 42-1, 42-2, and 42-3 can be implemented to generate an electrical signal corresponding to each vibration of the lift pins 41-1, 41-2, and 41-3.

[0048] In an exemplary embodiment, the first piezoelectric resonator 42-1 (also referred to as a "vibration generator") can be implemented to generate vibrations. For example, the first piezoelectric resonator 41-1 can generate a vibration signal to finely move a structure (e.g., a combined structure including lift pins and a wafer) in a specific frequency range. In an exemplary embodiment, at least one of the second piezoelectric resonator 42-2 and the third piezoelectric resonator 42-3 (in other words, a "vibration detector") can be implemented to detect a resonance frequency by changing a vibration signal into an electrical signal. At this time, the position of the wafer can be measured based on the difference in the detected resonance frequencies.

[0049] In an exemplary embodiment, each of the piezoelectric resonators 42-1, 42-2, and 42-3 can be implemented as a structure physically independent of the corresponding lift pin. For example, each of the piezoelectric resonators 42-1, 42-2, and 42-3 can be physically separated from the corresponding lift pins 41-1, 41-2, and 41-3 instead of being integrated with the corresponding lift pins 41-1, 41-2, and 41-3.

[0050] In addition, the device 40 for detecting the position of a wafer according to the inventive concept may further include a controller that receives an electrical signal from at least one second piezoelectric resonator and determines the position of the wafer based on the received electrical signal.

[0051] In addition, Figure 4 The number of the illustrated lift pins is 3, and the number of the piezoelectric resonators is also 3. However, it should be understood that the number of lift pins or the number of piezoelectric resonators according to the inventive concept is not limited thereto.

[0052] In addition, a device 40 for detecting the position of a wafer may detect the degree of position deviation based on a change in the resonance frequency according to the wafer position. In an exemplary embodiment, the resonance frequency may vary according to the length, width, or material of each lift pin.

[0053] Figure 5A and Figure 5B are diagrams showing the deviation of the wafer position in a device for detecting the position of a wafer according to an exemplary embodiment of the inventive concept. As Figure 5A shown, the wafer W may be disposed on a lift pin 41 above a support bracket 51 in a normal wafer position. As Figure 5B shown, the wafer W may be disposed on a lift pin 41 above a support bracket 51 in a deviated wafer position. Here, each of the lift pins 41 may be implemented to move up and down through the support bracket 51.

[0054] Figure 6A 、 Figure 6B and Figure 6C are diagrams showing predicting the position of a wafer by measuring the resonance frequency in a device for detecting the position of a wafer according to an exemplary embodiment of the inventive concept. As Figure 6A shown, the device 40 for detecting the position of a wafer may be regarded as a spring system (wafer lift pin structure). Here, the mass of the wafer is m wafer , and the mass of the lift pin is m pin . As Figure 6B shown, when the wafer is at the center, the spring constant is k center . As Figure 6C shown, when the position of the wafer is deviated, the spring constant is k shift .

[0055] The spring constant k of the structural system according to the change in the position of the wafer disposed on the lift pin may vary according to the change in the position of the wafer. Here, it may be assumed that the lift pin and the wafer disposed on the lift pin are a single elastic body or a mass-spring system. Generally, in a mass-spring system, the resonance frequency ω n is a function of the mass m and the spring constant k. The mass of the wafer and the lift pin is always the same, and the spring constant k may be determined by the structural form (shape) of the system (such as the position of the wafer). Therefore, the change in the wafer position may be regarded as a change in form. The change in form results in a change in the spring constant. For example, k shift < k center . That is, m center = m shift = m wafer + m pin .

[0056] Therefore, the resonance frequencies ω n,center and ωn,shift respectively satisfy the following equations.

[0057] [Equation 1]

[0058]

[0059] Here, ω n,center is the resonant frequency at the normal position of the wafer, and k center is the spring constant at the normal position of the wafer. m wafer is the mass of the wafer, m pin is the mass of the lift pin, ω n,shift and k center are the resonant frequency and the spring constant when the position of the wafer deviates.

[0060] In Equation 1, ω = fk and k are constants determined by the form (that is, the relative position of the wafer). Therefore, the position of the wafer on the lift pin can be predicted by measuring the change in the resonant frequency. That is, the device for detecting the position of the wafer according to the inventive concept can measure the change in the resonant frequency corresponding to the change in the spring constant of the wafer lift pin structure.

[0061] Figure 7A and Figure 7B are diagrams showing the results of measuring the resonant frequency according to the wafer position in the device for detecting the position of the wafer according to an exemplary embodiment of the inventive concept. As Figure 7A shown, the initial wafer position can be centered. As Figure 7B shown, the position of the wafer that has been moved by d (mm) may deviate. When the wafer position changes, the resonant frequency value measured by the sensor can change according to the moving distance d. That is, the resonant frequency when the wafer is at the center of the support bracket may be different from the resonant frequency when the wafer deviates from the center of the support bracket.

[0062] Figure 8 is a diagram showing the resonant frequency according to the degree of deviation of the wafer from the center in the device for detecting the position of the wafer according to an exemplary embodiment of the inventive concept. Referring to Figure 8 , as the distance of the wafer from the center increases, the resonant frequency measured by the sensor steadily decreases. Therefore, the wafer position can be accurately detected by the amount of change in the resonant frequency of the wafer lift pin structure.

[0063] Figure 9A , Figure 9B and Figure 9C are diagrams showing the lift pin assembly according to an exemplary embodiment of the inventive concept.

[0064] Figure 9AFIG. 0 is a view showing a lifting device 100 according to an exemplary embodiment of the inventive concept. The lifting device 100 may be a device configured to move a wafer W in a vertical direction in a substrate processing apparatus. In an exemplary embodiment, the wafer W moved in the vertical direction by the lifting device 100 may be a substrate including a wafer, a printed circuit board (PCB), etc. The lifting device 100 may move the substrate in the vertical direction to set the substrate on an electrostatic chuck and remove the substrate from the electrostatic chuck, and to load the substrate into a processing chamber and take out the substrate from the processing chamber.

[0065] In addition, the wafer W moved in the vertical direction by the lifting device 100 may be a moving ring. The form of plasma generated during substrate processing may be changed based on the vertical displacement of the moving ring. More specifically, if a part of the moving ring is etched due to repetition of substrate processing and the form of plasma generated during substrate processing is different from the previously predicted form, the lifting device 100 may move the moving ring in the vertical direction. Accordingly, the plasma generated during substrate processing may be generated in the previously predicted form.

[0066] The lifting device 100 may include a main body 110, a lifting pin 120, a pin guide 130, a bellows 140, a connection assembly 150 (e.g., a connector), a piezoelectric resonator 160, an actuator 170, and a controller 180. The main body 110 may be configured to support the above-described wafer W. For example, the wafer W may be disposed on the upper surface of the main body 110. In addition, a lifting hole H1 may be formed in the main body 110, and the lifting hole H1 may overlap with the wafer W in the vertical direction. In an exemplary embodiment, the main body 110 may be formed to surround an electrostatic chuck (not shown). The lifting pin 120 may be configured to move the wafer W disposed on the main body 110 in the vertical direction. More specifically, the lifting pin 120 may be configured to move in the lifting hole H1 of the main body 110 in the vertical direction to move the wafer W in the vertical direction. In an exemplary embodiment, the range of the resonance frequency of the wafer lifting pin structure may be determined according to the length, thickness, or material of the lifting pin. The pin guide 130 may be located in the lifting hole H1 of the main body 110 and may be configured to guide the movement of the lifting pin 120 in the vertical direction. The inner surface of the pin guide 130 may be spaced apart from the outer surface of the lifting pin 120 by a specific distance.

[0067] The bellows 140 may be coupled to the lower portion of the main body 110 and may be configured to move between a vacuum state and an atmospheric state. The vacuum state may include a state where there is no air and may also include a low-pressure state where the air pressure is 1 / 1000 mmHg or less. In an exemplary embodiment, the bellows 140 may form a lifting hole H1 at the top of the bellows 140 in the vacuum state and form a space adjacent to the load sensor in the atmospheric state. In an exemplary embodiment, the bellows 140 may include an upper flange 141, a lower flange 143, and a flexible tube 145. The upper flange 141 may be coupled to the lower portion of the main body 110 and may be configured to expose the lifting hole H1. The lower flange 143 may be disposed to be spaced apart from the flange 141 in the vertical direction and may be connected to the actuator 170. In an exemplary embodiment, the flexible tube 145 may be an elastic tube between the upper flange 141 and the lower flange 143 and may be configured to surround at least a portion of the lifting pin 120. The flexible tube 145 may be configured to be stretched or compressed according to the movement of the actuator 170. For example, as the actuator 170 moves downward, the flexible tube 145 may be stretched (e.g., extended), and as the actuator 170 moves upward, the flexible tube 145 may be compressed.

[0068] The connection assembly 150 may be coupled to the lower portion of the lifting pin 120. Additionally, the connection assembly 150 may be inside the bellows 140. More specifically, the connection assembly 150 may be between the lifting pin 120 and the piezoelectric resonator 160 within the flexible tube 145 of the bellows 140. In an exemplary embodiment, the connection assembly 150 may be a component configured to interfere with the downward movement of the lifting pin 120. However, the connection assembly 150 may be a component configured not to interfere with at least any one of the following: rotation based on a first axis extending in a direction parallel to the direction in which the lifting pin 120 extends, tilting based on the first axis, and sliding in a plane perpendicular to the first axis. That is, the connection assembly 150 may restrict the downward movement of the lifting pin 120 but may allow at least one of rotation, tilting, and sliding of the lifting pin 120. In an exemplary embodiment, the connection assembly 150 may be a component configured not to interfere with all of the rotation of the lifting pin 120 about the first axis, the tilting about the first axis, and the sliding in a plane perpendicular to the first axis.

[0069] The connection assembly 150 may interfere with the downward movement of the lifting pin 120 but may not interfere with the rotation, tilting, and sliding of the lifting pin 120. Additionally, the lifting pin 120 may transmit only the load in the vertical direction to the load sensor.

[0070] The piezoelectric resonator 160 may be implemented to output a vibration signal to the lifting pin 120 or detect a resonance frequency corresponding to the vibration of the lifting pin 120.

[0071] The load sensor may also be included on the top and / or bottom of the piezoelectric resonator 160. The load sensor may accurately measure the load applied to the wafer W in the vertical direction. The load sensor may be located at the bottom of the connection assembly 150. The load sensor may measure the load generated as the lift pin 120 moves in the vertical direction. More specifically, the load sensor may be a sensor that accommodates the load generated according to the vertical movement of the lift pin 120 and converts the load into an electrical signal. The load sensor may generate load information according to the vertical displacement of the lift pin 120 and transmit the load information to the controller 180. In an exemplary embodiment, the load sensor may be a load unit including at least one of a strain gauge load unit, a beam load unit, a platform load unit, and a canister load unit. However, the load sensor is not limited thereto, and may include various types of sensors capable of converting the load generated according to the vertical movement of the lift pin 120 into an electrical signal.

[0072] In an exemplary embodiment, the connection assembly 150 may be configured not to interfere with any of the rotation, tilt, and sliding of the lift pin 120. Accordingly, the lift pin 120 may not only transmit the vertical load generated according to the vertical movement of the lift pin 120 to the load sensor, but the load sensor may convert only the vertical load transmitted from the lift pin 120 into an electrical signal.

[0073] The actuator 170 may be located below the bellows 140. More specifically, the actuator 170 may be located below the lower flange 143 of the bellows 140. The actuator 170 may be configured to move the lift pin 120 in the vertical direction. In an exemplary embodiment, the actuator 170 may move in the vertical direction by a power member such as a motor or a hydraulic device. The actuator 170 may move the lift pin 120 in a direction substantially the same as the moving direction of the actuator 170. In an exemplary embodiment, as the actuator 170 moves up and down, the flexible tube 145 of the bellows 140 may be stretched or compressed. For example, when the actuator 170 moves downward, the flexible tube 145 may be stretched (e.g., extended). Additionally, when the actuator 170 moves upward, the flexible tube 145 may be compressed.

[0074] The controller 180 may be configured to generally control the vertical movement of the wafer W by using the lifting device 100. In an exemplary embodiment, the controller 180 may be connected to the load sensor and the actuator 170. The controller 180 may determine the load applied to the wafer W based on the load information generated by the load sensor. For example, when the wafer W moved in the vertical direction by the lift pin 120 is a substrate and the controller 180 determines that the load applied to the substrate by the lift pin 120 is excessive, the controller 180 may control the actuator 170 to change the vertical position of the lift pin 120. In an exemplary embodiment, the controller 180 may determine the initial contact point between the wafer W and the lift pin 120 based on the load information generated by the load sensor. The initial contact point CP may be defined as the vertical position of the lift pin 120 immediately before the wafer W starts to contact the lift pin 120 and the wafer W moves upward. In an exemplary embodiment, when the wafer W moved in the vertical direction by the lift pin 120 is a moving ring, the controller 180 may determine the initial contact point CP between the moving ring and the lift pin 120 based on the load magnitude measured by the load sensor.

[0075] In addition, the controller 180 may be implemented to detect the resonance frequency according to the electrical signal received from the piezoelectric resonator 160 and determine the position of the wafer by using the detected resonance frequency. Here, the resonance frequency of the wafer lift pin structure may change according to the position of the wafer.

[0076] In some exemplary implementations, the controller 180 may be implemented as hardware, firmware, software, or any combination thereof. For example, the controller 180 may be a computing device, such as a workstation computer, a desktop computer, a laptop computer, a tablet computer, etc. The controller 180 may be a simple controller, a complex processor such as a microprocessor, a central processing unit (CPU), a graphics processing unit (GPU), or a data processing unit (DPU), a processor configured by software, dedicated hardware, or firmware. The controller 180 may be implemented by, for example, a general-purpose computer or dedicated hardware such as a digital signal processor (DSP), a field-programmable gate array (FPGA), and an application-specific integrated circuit (ASIC).

[0077] In an exemplary embodiment, the operation of the controller 180 may be implemented as instructions stored on a machine-readable medium that can be read and executed by one or more processors. Here, the machine-readable medium may include any mechanical device for storing or transmitting information in a form readable by a machine (e.g., a computing device). For example, the machine-readable medium may include a read-only memory (ROM), a random access memory (RAM), a magnetic disk storage medium, an optical storage medium, a flash memory device, and electrical, optical, acoustic, or other forms of radio signals (e.g., carrier waves, infrared signals, digital signals, etc.) and any other signals.

[0078] The controller 180 can be implemented by firmware, software, routines, and instructions for moving the wafer W in the vertical direction by the lift pins 120. For example, the controller 180 can be implemented by software that receives data for feedback, generates signals for moving the wafer W by the lift pins 120, and performs predetermined operations.

[0079] The lift device 100 of the inventive concept can measure the load applied to the wafer W in real time and control the lift pins 120 in real time. In addition, the lift device 100 according to an exemplary embodiment of the inventive concept can accurately measure the position of the wafer in real time through a piezoelectric resonator.

[0080] Figure 9B FIG. is a view showing a lift device 100a according to another exemplary embodiment of the inventive concept. Referring to Figure 9B , the lift device 100a can include a main body 110, lift pins 120, pin guides 130, bellows 140, connection components 150, piezoelectric resonators 160, actuators 170, and a controller 180. As Figure 9B shown, the piezoelectric resonator 160 of the lift device 100a can be outside the bellows 140. More specifically, the piezoelectric resonator 160 can be between the lower flange 143 of the bellows 140 and the actuator 170.

[0081] Figure 9C FIG. is a view showing a lift device 100b according to another exemplary embodiment of the inventive concept. Referring to Figure 9C , the lift device 100b can include a main body 110, lift pins 120, pin guides 130, bellows 140, connection components 150, piezoelectric resonators 160, actuators 170, and a controller 180. As Figure 9C shown, the lower flange 143 of the bellows 140 of the lift device 100b can include a setting portion 143a and a deformable portion 143b. In an exemplary embodiment, the setting portion 143a can be a portion of the lower flange 143 that is disposed on the actuator 170 and coupled to the flexible tube 145. In an example, the deformable portion 143b can be a portion of the lower flange 143 that is coupled to the connection component 150 inside the setting portion 143a. In addition, the deformable portion 143b can include a material that can be deformed by an external force and can be physically deformed by the upward and downward movement of the lift pins 120 or the pressure inside the flexible tube 145. More specifically, when a downward external force is applied to the deformable portion 143b due to the contact between the wafer W and the lift pins 120, the deformable portion 143b can bend downward. In addition, when the inside of the bellows 140 is formed in a vacuum state, the deformable portion 143b can bend upward.

[0082] Throughout the specification, when a component is described as "including" a specific element or group of elements, it is to be understood that, unless the context indicates otherwise, the component is formed only of that element or group of elements, or that element or group of elements may be combined with additional elements to form the component. On the other hand, the term "consisting of" means that the component is formed only of the listed element(s).

[0083] In an exemplary embodiment, the load sensor may be coupled to a lower portion of the deformable part 143b. The load sensor may be configured to measure a load based on a degree of deformation of the deformable part 143b according to a displacement of the lifting pin 120 in a vertical direction and generate load information. As long as the load sensor of the lifting device 100b according to the inventive concept can be outside the bellows 140, the load sensor can be free from the influence of the environment inside the bellows 140 and can be easily managed.

[0084] In addition, the piezoelectric resonator and the controller according to the inventive concept may be implemented in various combinations for a device for detecting the position of a wafer.

[0085] Figure 10A and Figure 10B are diagrams showing a device for detecting the position of a wafer. Referring to Figure 10A , a device 400 for detecting the position of a wafer may include a plurality of piezoelectric resonators (PRs) 411 to 41k (k is an integer of 2 or greater) and a controller 420. Each of the plurality of piezoelectric resonators 411 to 41k may be implemented to output a resonance frequency signal according to the vibration of a corresponding lifting pin. The controller 420 may be implemented to receive the resonance frequency signals from each of the piezoelectric resonators 411 to 41k and determine the position of the wafer using the received resonance frequency signals.

[0086] Referring to Figure 10B , a device 400a for detecting the position of a wafer may include a first piezoelectric resonator 410-1, a second piezoelectric resonator 410-2, and a controller 420a. The first piezoelectric resonator 410-1 may be implemented to output a resonance frequency signal by causing the vibration of a corresponding lifting pin. The second piezoelectric resonator 410-2 may be implemented to receive the resonance frequency signal of the first piezoelectric resonator 410-1 and output the resonance frequency signal to the controller 420a. The controller 420a may be implemented to receive the resonance frequency signal from the second piezoelectric resonator 410-2 and determine the position of the wafer using the received resonance frequency signal.

[0087] Figure 11 is a flowchart showing an operation of detecting the position of a wafer of a semiconductor manufacturing device according to an exemplary embodiment of the inventive concept. Referring to Figures 1 to 11, a semiconductor manufacturing apparatus may perform a wafer position detection operation as follows. A wafer may be disposed on a lift pin (S110). A resonance frequency corresponding to the resonance of the lift pin may be detected using a piezoelectric resonator (S120). The position of the wafer may be measured using the detected resonance frequency (S130).

[0088] In an exemplary embodiment, the wafer, the lift pin, and the piezoelectric resonator may be implemented as physically separate structures. For example, the piezoelectric resonator may not be integrated with the corresponding lift pin but may be physically separable from the corresponding lift pin. In an exemplary embodiment, the number of piezoelectric resonators may be less than or equal to the number of lift pins. In an exemplary embodiment, the piezoelectric resonator may be implemented below the corresponding lift pin among the lift pins. In an exemplary embodiment, the piezoelectric resonator may be implemented in a connection portion of the corresponding lift pin among the lift pins. For example, the connection portion of the lift pin may connect the lift pin to an element disposed below the lift pin, such as a part of the bellows 140 or a part of the actuator 170. In an exemplary embodiment, an initial resonance frequency may be detected when the wafer is located at the center of the support bracket. In an exemplary embodiment, the deviation of the position of the wafer may be determined by comparing the initial resonance frequency with the measured resonance frequency. In an exemplary embodiment, when the wafer deviates from the center of the support bracket, the resonance frequency may be lower than the initial resonance frequency. In an exemplary embodiment, a vibration signal may be generated to vibrate the wafer lift pin structure. Here, the vibration signal may be generated from a piezoelectric resonator different from the piezoelectric resonator used to measure the resonance frequency.

[0089] The apparatus and method for detecting the position of a wafer according to an exemplary embodiment of the inventive concept may detect the position of the wafer in a processing chamber in real time.

[0090] The apparatus and method for detecting the position of a wafer according to an exemplary embodiment of the inventive concept may measure the position of the wafer on the lift pin in real time.

[0091] Since the sensor is attached outside the processing space, the apparatus and method for detecting the position of a wafer according to an exemplary embodiment of the inventive concept do not affect the processing.

[0092] The apparatus and method for detecting the position of a wafer according to an exemplary embodiment of the inventive concept may accurately measure the position of the wafer.

[0093] The devices described herein can be implemented using hardware components, software components, or a combination thereof. For example, the devices and components described in the embodiments can be implemented using one or more general-purpose or special-purpose computers, such as processors, controllers, arithmetic logic units (ALUs), digital signal processors, microcomputers, field programmable gate arrays (FPGAs), programmable logic units (PLUs), microprocessors, or any other device capable of executing and responding to instructions. The processing device can be implemented using one or more general-purpose or special-purpose computers, such as, by way of example, processors, controllers, and arithmetic logic units, digital signal processors, microcomputers, field programmable gate arrays, programmable logic units, microprocessors, or any other device capable of responding and executing instructions in a defined manner. The processing device can run an operating system (OS) and one or more software applications running on the OS. The processing device can also access, store, operate on, process, and create data in response to the execution of software. For the sake of brevity, the description of the processing device is used in the singular; however, those skilled in the art will understand that the processing device can include multiple processing elements and multiple types of processing elements. For example, the processing device can include multiple processors or one processor and one controller. Additionally, different processing configurations are possible, such as parallel processors.

[0094] Software can include a computer program, a piece of code, instructions, or some combination thereof to independently or jointly direct or configure the processing device to operate as required. Software and data can be permanently or temporarily embodied in any type of machine, component, physical or virtual facility, computer storage medium, or device, or in a propagated signal wave capable of providing instructions or data to, or being interpreted by, the processing device. Software can also be distributed over network-connected computer systems such that the software is stored and executed in a distributed manner. Software and data can be stored by one or more non-transitory computer-readable recording media.

[0095] The wafer position detection device according to an embodiment of the present invention can detect the degree of position displacement by a change in the resonance frequency corresponding to the wafer position. In an embodiment, a piezoelectric resonator having a resonance frequency range that matches the structure may be used. In an embodiment, the spring constant value and the resonance frequency range of the structure may be determined by the length, width, and material specifications of the lift pin. In an embodiment, the wafer, the lift pin, and the piezoelectric resonator may have physically independent structures. In an embodiment, at least one resonator may be used, and a plurality of resonators up to the number of pins may be used. In an embodiment, the frequency measurement resonator may be implemented in a structure applied to the lower end of the lift pin or the connection portion of the lift pin. The wafer position detection device and the operation method can detect the position of the wafer in the processing chamber in real time. The wafer position detection device and the operation method can measure the position of the wafer on the lift pin in real time. Since the sensor is attached to the outside of the processing space, the wafer position detection device and the operation method do not affect the processing. The wafer position detection device and the operation method can accurately measure the position of the wafer.

[0096] Although example embodiments have been shown and described above, those skilled in the art will understand that modifications and variations can be made without departing from the scope of the inventive concept.

Claims

1. An apparatus for detecting the position of a wafer, the apparatus comprising: A plurality of lift pins configured to place the wafer on a support bracket; And A plurality of piezoelectric resonators respectively at lower portions of the plurality of lift pins, Wherein at least one first piezoelectric resonator among the plurality of piezoelectric resonators is configured to vibrate a corresponding lift pin among the plurality of lift pins, Wherein at least one second piezoelectric resonator among the plurality of piezoelectric resonators is configured to detect a resonance frequency of a combined structure including the wafer and the plurality of lift pins, the resonance frequency corresponding to the vibration, and Wherein the apparatus further comprises a controller configured to determine the position of the wafer based on a change in the resonance frequency.

2. The device according to claim 1, wherein, Each of the plurality of lift pins is configured to move vertically through the support bracket.

3. The device according to claim 1, wherein, The at least one first piezoelectric resonator is configured to generate a vibration signal within a predetermined frequency range.

4. The device according to claim 3, wherein The at least one second piezoelectric resonator is configured to detect the resonance frequency by converting the vibration signal into an electrical signal.

5. The apparatus according to claim 1, wherein The at least one second piezoelectric resonator is configured to output an electrical signal corresponding to the resonance frequency, and The controller is configured to receive the electrical signal and determine the position of the wafer based on the received electrical signal.

6. The device according to claim 5, wherein, The controller is configured to measure a change in the resonance frequency corresponding to a change in the spring constant of the combined structure.

7. The device according to claim 6, wherein A first spring constant corresponding to the wafer being at a central position of the support bracket is greater than a second spring constant corresponding to the wafer being off - center.

8. The device according to claim 1, wherein The resonance frequency decreases as the wafer is positioned farther from the center of the support bracket.

9. The device according to claim 1, wherein The resonance frequency changes according to the length, width, or material of each of the plurality of lift pins.

10. The device according to claim 1, wherein, Each of the plurality of piezoelectric resonators is physically separable from a corresponding lift pin.

11. An apparatus for detecting the position of a wafer, the apparatus comprising: A plurality of piezoelectric resonators; And A controller configured to receive an electrical signal from at least one of the plurality of piezoelectric resonators and determine the position of the wafer based on the received electrical signal, the electrical signal corresponding to a resonance frequency of a combined structure including the wafer and a plurality of lift pins.

12. The device according to claim 11, wherein, Each of the plurality of piezoelectric resonators is located at a lower portion of a corresponding lift pin among the plurality of lift pins.

13. The device according to claim 11, wherein, Each of the plurality of piezoelectric resonators is located at a connecting portion of a corresponding lift pin among the plurality of lift pins.

14. The device according to claim 11, wherein, At least one piezoelectric resonator among the plurality of piezoelectric resonators is configured to generate a vibration signal.

15. The device according to claim 14, wherein, The remaining piezoelectric resonators among the plurality of piezoelectric resonators are configured to generate the electrical signal corresponding to the resonance frequency by detecting the vibration signal.

16. An apparatus for detecting the position of a wafer, the apparatus comprising: A lift pin configured to move vertically in a hole of a support bracket to place the wafer on the support bracket; A connector connected to a lower portion of the lift pin; A piezoelectric resonator, which is located below the connector and is configured to detect the resonance frequency of the lift pin; An actuator, which is configured to vertically move the lift pin; And A controller, which is configured to control the actuator, wherein the controller is configured to receive an electrical signal corresponding to the resonance frequency from the piezoelectric resonator and determine the position of the wafer based on the electrical signal.

17. The device according to claim 16, wherein, The range of the resonance frequency is determined according to the length, thickness or material of the lift pin.

18. The apparatus according to claim 16, wherein, The controller is configured to control the piezoelectric resonator to generate a vibration signal.

19. The apparatus according to claim 16, wherein, The resonance frequency changes according to the position of the wafer.

20. The apparatus according to claim 16, wherein The resonance frequency when the wafer is located at the center of the support bracket is different from the resonance frequency when the wafer deviates from the center of the support bracket.

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