Substrate testing apparatus and desorption force measurement method using the same

Abstract

A substrate testing device is provided that is capable of measuring a dechucking force with high reliability by adding a vertical force measuring section that is capable of pushing or pulling a substrate in a vertical direction. The device includes an electrostatic chuck that supports a substrate, a vertical force measuring section that is arranged on the electrostatic chuck and that pushes or pulls the substrate in a vertical direction, an electrostatic chuck power applying section that applies a driving voltage and a first ground voltage to the electrostatic chuck, and a substrate power applying section that applies a second ground voltage to the substrate, wherein the substrate is charged by applying the driving voltage to the electrostatic chuck and the second ground voltage to the substrate, then the substrate is discharged by applying the first ground voltage to the electrostatic chuck and the second ground voltage to the substrate, and thereafter the dechucking force of the substrate is measured by pulling the substrate in the vertical direction by the vertical force measuring section.

Description

Technical Field

[0001] This invention relates to a substrate testing apparatus and a method for measuring the dechucking force using the substrate testing apparatus. More specifically, this invention relates to a substrate testing apparatus for evaluating the dechucking force of an electrostatic chuck and a method for measuring the dechucking force using the substrate testing apparatus. Background Technology

[0002] Generally, plasma treatment methods for surfaces such as semiconductor wafers and flat panel display substrates are broadly classified into capacitively coupled plasma (CCP) treatment and inductively coupled plasma (ICP) treatment.

[0003] As described above, plasma-based substrate processing refers to a process in which high-frequency electricity is applied to a vacuum chamber, causing the gas supplied to the chamber to flow in a plasma state, and the high-energy electrons or free radicals formed at this time are used to etch and remove thin films. For successful execution of plasma-based substrate processing, the clamping (adsorption) and declamping (desorption) processes of the semiconductor substrate inside the chamber are essential and crucial steps.

[0004] Typically, substrate holding methods in process chambers used for manufacturing semiconductor devices include mechanical clamping and vacuum chucks. However, in recent years, the use of electrostatic chucks (ESCs), which offer excellent particle and process uniformity, has increased dramatically. However, when using such ESCs, during the dechucking process after plasma treatment, static electricity generated by residual charges on the substrate surface is not completely removed, leading to problems such as sticking. This can cause the substrate to break within the reaction chamber, or the substrate may be incorrectly positioned on the paddles of the substrate holding robot during unloading from the chamber.

[0005] Therefore, a method for removing residual surface charge on a substrate during desorption has recently been studied, such as applying a 0V voltage to the desorption voltage application section for a predetermined time or grounding it.

[0006] However, this existing method has the following problem: as the amount of electrostatic chuck used increases, the electrostatic capacity of the electrostatic chuck increases. Therefore, when the amount of surface charge on the substrate increases, it takes a considerable amount of time and the surface charge cannot be completely removed. Summary of the Invention

[0007] Technical problems to be solved

[0008] A method is needed to evaluate whether the process of separating a substrate from an electrostatic chuck—that is, whether the desorption process is performed successfully. To this end, in the prior art, a horizontal sliding method is used to confirm whether the surface charge remaining on the substrate is sufficiently removed during the desorption process. However, in this method, the reliability of the desorption force evaluation method is low because it uses the force pushing the substrate in the horizontal direction to measure the dechucking force acting on the substrate in the vertical direction.

[0009] In addition, in the existing technology, the desorption force is directly and manually evaluated by people, which results in large dispersion and low evaluation efficiency.

[0010] The technical problem to be solved by the present invention is to provide a substrate testing device, which can measure the desorption force with high reliability by adding a vertical force measuring part that can push or pull the substrate in the vertical direction.

[0011] The technical issues of this invention are not limited to those described above. Those skilled in the art can clearly understand other technical issues not mentioned from the following description.

[0012] Solution

[0013] To solve the above-mentioned technical problems, a substrate testing apparatus according to one aspect of the present invention may include: an electrostatic chuck for supporting a substrate; a vertical force measuring unit disposed on the electrostatic chuck and capable of pushing or pulling the substrate in a vertical direction; an electrostatic chuck power application unit for applying a driving voltage and a first ground voltage to the electrostatic chuck; and a substrate power application unit for applying a second ground voltage to the substrate, wherein the substrate is charged by applying the driving voltage to the electrostatic chuck by the electrostatic chuck power application unit and applying the second ground voltage to the substrate by the substrate power application unit, and the substrate is discharged by applying the first ground voltage to the electrostatic chuck by the electrostatic chuck power application unit and applying the second ground voltage to the substrate by the substrate power application unit; and the desorption force of the substrate is measured by the vertical force measuring unit.

[0014] Before the substrate is charged, the method may further include setting an initial charge on the substrate by applying a second ground voltage to the substrate.

[0015] When setting the initial charge on the substrate, the electrostatic chuck power application unit may not apply a driving voltage and a first ground voltage to the electrostatic chuck.

[0016] The substrate can be charged for a first operating time, and the substrate can be discharged for a second operating time different from the first operating time.

[0017] After the substrate is charged and before it is discharged, a driving voltage can be not applied to the electrostatic chuck and a second ground voltage can be not applied to the substrate to keep the substrate in a charged state.

[0018] The substrate can be charged for a first operating time, the substrate can be discharged for a second operating time shorter than the first operating time, and the substrate can remain charged for a third operating time shorter than the second operating time.

[0019] The electrostatic chuck may also include a clamping element arranged below the electrostatic chuck and securing the electrostatic chuck.

[0020] The measurement of the desorption force of the substrate by pulling the substrate in the vertical direction by the vertical force measuring unit can be performed without the second grounding voltage being applied to the substrate and without the electrostatic chuck being applied with the driving voltage and the first grounding voltage.

[0021] After the substrate is discharged, residual charge may remain inside the substrate. Through the residual charge, electrostatic attraction can be generated between the substrate and the electrostatic chuck, and the desorption force can be determined based on the electrostatic attraction.

[0022] The substrate testing apparatus may further include: a testing chamber, which includes an internal space for processing the substrate; and a transport unit, which is arranged below the testing chamber and is used to transport the testing chamber.

[0023] The substrate testing apparatus may further include: a motor, located on the upper surface of the testing chamber, which provides power to push or pull the substrate to the vertical force measuring unit, wherein the motor can provide power to the vertical force measuring unit in a direction perpendicular to the substrate via a ball screw method.

[0024] The motor can provide power to the vertical force measuring unit, enabling the vertical force measuring unit to pull the substrate at a first speed or a second speed, and the first speed may be different from the second speed.

[0025] The substrate testing apparatus may also include a damper, arranged between the motor and the vertical force measuring unit, for reducing vibrations generated as the motor supplies power to the vertical force measuring unit.

[0026] To solve the above-mentioned technical problems, a desorption force measurement method according to another aspect of the present invention may include the following steps: placing a substrate on an electrostatic chuck; charging the substrate by applying a driving voltage to the electrostatic chuck and applying a second grounding voltage to the substrate; then discharging the substrate by applying a first grounding voltage to the electrostatic chuck and applying a second grounding voltage to the substrate; and then measuring the desorption force of the substrate by pulling the substrate in the vertical direction by a vertical force measuring unit arranged on the substrate.

[0027] Before charging the substrate, the method further includes setting an initial charge on the substrate by applying a second ground voltage to the substrate.

[0028] When setting the initial charge on the substrate, it is not necessary to apply a driving voltage and a first ground voltage to the electrostatic chuck.

[0029] After charging the substrate and before discharging the substrate, the process may further include: keeping the substrate charged by not applying a driving voltage to the electrostatic chuck and not applying a second grounding voltage to the substrate.

[0030] The step of measuring the deadsorption force of the substrate by pulling the substrate in the vertical direction by the vertical force measuring unit can be performed without applying a driving voltage and a first ground voltage to the electrostatic chuck.

[0031] After the substrate is discharged, residual charge may remain inside the substrate. Through the residual charge, electrostatic attraction can be generated between the substrate and the electrostatic chuck, and the desorption force can be determined based on the electrostatic attraction.

[0032] Specific details of other embodiments are included in the detailed description and accompanying drawings. Attached Figure Description

[0033] Figure 1 This is a cross-sectional view used to illustrate a substrate testing apparatus according to an embodiment of the present invention.

[0034] Figure 2 and Figure 3 This is a flowchart illustrating a method for evaluating desorption force according to an embodiment of the present invention.

[0035] Figures 4 to 7 This is a diagram illustrating intermediate steps of a desorption force evaluation method according to an embodiment of the present invention.

[0036] Figure 8 It is used to explain in Figure 3 A graph showing the applied voltage state and the wafer lifting state during the intermediate steps of the desorption force evaluation method.

[0037] Figure 9 It is used to explain in Figure 3 A graph showing the speed at which the vertical force measuring unit pulls the substrate during an intermediate step in the desorption force evaluation method.

[0038] Figure 10 This is a flowchart illustrating a method for evaluating desorption force according to an embodiment of the present invention.

[0039] Figure 11 This is a diagram illustrating intermediate steps of a desorption force evaluation method according to an embodiment of the present invention.

[0040] Figure 12 It is used to explain in Figure 10 A graph showing the applied voltage state and the wafer lifting state during the intermediate steps of the desorption force evaluation method.

[0041] Explanation of reference numerals in the attached figures

[0042] 100: Substrate; 220: Electrostatic chuck

[0043] 230: Electrostatic chuck electrode; 300: Electrostatic chuck power application section

[0044] 400: Substrate power application part; 500: Clamping member

[0045] 610: Vertical force measuring unit; HV: Drive voltage

[0046] GND1: First grounding voltage; GND2: Second grounding voltage Detailed Implementation

[0047] Preferred embodiments of the invention will be described in detail below with reference to the accompanying drawings. The advantages and features of the invention, as well as the methods of achieving these advantages and features, will become apparent from the embodiments described in detail below in conjunction with the accompanying drawings. However, the invention is not limited to the embodiments disclosed below, but can be implemented in various different forms, and these embodiments are provided only to complete the disclosure of the invention and to fully inform those skilled in the art of the scope of the invention, and the invention is defined only by the scope of the claims. Throughout the specification, the same reference numerals refer to the same constituent elements.

[0048] When an element or layer is referred to as being "above" or "on top of" another element or layer, it includes not only being directly above the other element or layer, but also the case where another layer or element is intervening in between. Conversely, when an element is referred to as being "directly above" or "right above," it indicates that there is no other element or layer intervening in between.

[0049] Although terms such as "first," "second," etc., are used to describe various elements, constituent elements, and / or parts, it is clear that these elements, constituent elements, and / or parts are not limited by these terms. These terms are used only to distinguish one element, constituent element, or part from other elements, constituent elements, or parts. Therefore, within the technical concept of this invention, the first element, first constituent element, or first part mentioned below can obviously also be a second element, second constituent element, or second part.

[0050] The terminology used in this specification is for describing embodiments and is not intended to limit the invention. In this specification, the singular form also includes the plural form unless otherwise specified in the sentence. The terms "comprises" and / or "comprising" as used in this specification mean including the mentioned constituent elements, steps, operations, and / or components, without excluding the presence or addition of more than one other constituent element, step, operation, and / or component.

[0051] This invention relates to a substrate testing apparatus and a method for evaluating the dechucking force of a substrate by means of a vertical force measuring unit capable of pushing or pulling the substrate in a vertical direction. Hereinafter, exemplary embodiments of the invention will be described in detail with reference to the accompanying drawings.

[0052] Figure 1 This is a cross-sectional view used to illustrate a substrate testing apparatus according to an embodiment of the present invention.

[0053] Reference Figure 1 According to some embodiments, a substrate testing apparatus may include a test chamber 10, a substrate 100, a substrate support 200, an electrostatic chuck power application unit 300, a substrate power application unit 400, a clamping member 500, and a driving unit 600. The substrate testing apparatus may be a testing device for evaluating the de-adhesion force of the substrate 100.

[0054] The test chamber 10 may include an internal space 13 for processing the substrate 100. The test chamber 10 may also include a main body 11 and a frame 12.

[0055] The main body 11 can support the structure of the substrate testing apparatus. That is, the main body 11 can support the substrate 100, the substrate support 200, and the clamping member 500. The main body 11 can be arranged below the substrate 100, the substrate support 200, and the clamping member 500.

[0056] The frame portion 12 can be formed from the upper surface edge of the main body portion 11. The frame portion 12 can be arranged on the main body portion 11. The frame portion 12 can surround the internal space of the main body portion 11. The internal space 13 of the test chamber 10 can be secured by the frame portion 12.

[0057] The substrate 100, substrate support 200, electrostatic chuck power application part 300, substrate power application part 400, clamping member 500, and drive part 600 can be arranged in the internal space 13 of the test chamber 10. However, this is merely an example, and the technical spirit of the present invention is not limited thereto.

[0058] According to some embodiments, the substrate testing apparatus may further include a transport unit 700. The transport unit 700 may be arranged below the test chamber 10. The transport unit 700 may transport the test chamber 10.

[0059] Although the conveyor 700 is shown in the shape of a wheel, the technical spirit of the present invention is not limited thereto.

[0060] The substrate support 200 may include a base 210, an electrostatic chuck 220, and an electrostatic chuck electrode 230. The electrostatic chuck 220 may be disposed on the base 210.

[0061] The electrostatic chuck 220 uses electrostatic force to support the substrate 100 placed on the electrostatic chuck 220. The electrostatic chuck 220 may be made of ceramic material. The electrostatic chuck 220 may be combined with the base 210 for fixation to the base 210.

[0062] The base 210 can be arranged below the electrostatic chuck 220.

[0063] The lower portion of the base 210 may have a wider shape in the horizontal direction. The lower portion of the base 210 may have a larger diameter. As shown, the lower portion of the base 210 is wider than the upper portion; therefore, the clamping member 500 can provide a handle for securing the base 210. Thus, the base 210 can be secured by the clamping member 500.

[0064] An electrostatic chuck electrode 230 may be disposed in an electrostatic chuck 220. The electrostatic chuck electrode 230 receives a DC voltage for clamping the substrate 100 and attracts the substrate 100 by electrostatic force. Then, a desorption process is performed to separate the substrate 100 from the electrostatic chuck 220.

[0065] The electrostatic chuck power application unit 300 can apply a driving voltage HV and a first ground voltage GND1 to the electrostatic chuck 220. The electrostatic chuck power application unit 300 can also directly apply voltage to the electrostatic chuck 220. However, this is merely an example, and the spirit of the invention is not limited thereto.

[0066] The electrostatic chuck power application unit 300 may include a drive voltage application unit 310, a first ground voltage application unit 320, a control unit 330, and a switch 340.

[0067] The drive voltage application unit 310 can apply a drive voltage HV to the electrostatic chuck 220. The drive voltage application unit 310 can use a DC power supply. However, this is merely an example, and the technical spirit of the present invention is not limited thereto.

[0068] The first grounding voltage application unit 320 can apply a first grounding voltage GND1 to the electrostatic chuck 220.

[0069] The control unit 330 can be arranged between the drive voltage application unit 310 and the first ground voltage application unit 320. The control unit 330 can determine whether to apply the drive voltage HV or the first ground voltage GND1 to the electrostatic chuck 220.

[0070] Furthermore, the electrostatic chuck power application unit 300 can stop applying voltage via switch 340. For example, the voltage application can be stopped by disconnecting the switch 340 provided on the power line used for applying voltage.

[0071] The substrate power application unit 400 can apply a second ground voltage GND2 to the substrate 100. The substrate power application unit 400 can also directly apply voltage to the substrate 100. However, this is merely an example, and the spirit of the invention is not limited thereto.

[0072] In the accompanying drawings, the substrate power application unit 400 and the electrostatic chuck power application unit 300 are shown using different ground voltage sources, but this is merely an example, and the technical concept of the present invention is not limited thereto. For example, the second ground voltage GND2 applied by the substrate power application unit 400 can use the same power source as the first ground voltage GND1 applied by the electrostatic chuck power application unit 300.

[0073] The clamping member 500 may be arranged on the upper surface of the main body portion 11. The clamping member 500 may be arranged at the edge of the upper surface of the main body portion 11. The clamping members 500 may be formed in pairs on the main body portion 11. However, this is merely an example, and the technical spirit of the present invention is not limited thereto.

[0074] The clamping member 500 can be arranged below the electrostatic chuck 220. The clamping member 500 can be arranged on the side of the substrate support portion 200. The clamping member 500 can fix the substrate support portion 200. Specifically, the clamping member 500 can fix the electrostatic chuck 220.

[0075] For example, the clamping member 500 may be integrally formed around the base 210.

[0076] The clamping member 500 may have a hook shape. Therefore, the clamping member 500 can be fixedly arranged on the base 210 of the substrate support portion 200.

[0077] The shape of the clamping member 500 is merely an example, and the technical spirit of the present invention is not limited thereto. The shape of the clamping member 500 may be suitable for the shape of the electrostatic chuck 220 fixedly arranged on the clamping member 500.

[0078] According to some embodiments, the substrate testing apparatus can replace the electrostatic chuck 220 by releasing the electrostatic chuck 220 from the clamp 500.

[0079] As shown in the figure, a plate can be formed between the clamping member 500 and the main body 11. This is merely an example for the stability considerations of the substrate testing device, and the technical concept of the present invention is not limited thereto.

[0080] For example, the clamping member 500 may be formed on the main body portion 11. The clamping member 500 may contact the main body portion 11.

[0081] The drive unit 600 can be arranged above the electrostatic chuck 220. Specifically, the drive unit 600 can be arranged above the substrate 100. The drive unit 600 may include a vertical force measuring unit 610, a motor 620, and a damper 630.

[0082] The vertical force measuring unit 610 can be arranged above the electrostatic chuck 220. Specifically, the vertical force measuring unit 610 can be arranged above the substrate 100. The vertical force measuring unit 610 can contact the substrate 100.

[0083] Various devices, such as push-pull gauges and load cells, can be applied to the vertical force measuring unit 610. However, this is merely an example, and the spirit of the invention is not limited thereto. The vertical force measuring unit 610 can be a structure that measures the force in the vertical direction of the substrate 100 when measuring electrostatic attraction by pulling the substrate 100.

[0084] However, the method by which the vertical force measuring unit 610 measures the force in the vertical direction of the substrate 100 does not limit the technical concept of the present invention. For example, when a load cell is used as the vertical force measuring unit 610, the vertical force can be measured by the amount of deformation of the load cell under load. In this case, the vertical force measuring unit 610 may not include the motor 620 for providing power. In the present invention, for ease of explanation, a push-pull gauge will be used as an example for description.

[0085] The vertical force measuring unit 610 can push or pull the substrate 100 in the vertical direction.

[0086] The vertical force measuring unit 610 can be used to measure the desorption force by pulling the substrate 100 in a vertical direction after it has been adhered to the substrate 100. The method for measuring the desorption force will be described in detail below.

[0087] The motor 620 can be arranged on the vertical force measuring unit 610. The motor 620 can be arranged on the outer wall of the test chamber 10. The motor 620 can be arranged on the upper surface of the test chamber 10. However, this is merely an illustrated example, and the spirit of the invention is not limited thereto.

[0088] For example, the motor 620 can be arranged inside the interior space 13 of the test chamber 10.

[0089] The motor 620 can provide power to the vertical force measuring unit 610 to push or pull the substrate 100. The motor 620 can also provide power to the vertical force measuring unit 610 in a direction perpendicular to the substrate 100. For example, the motor 620 can provide power to the vertical force measuring unit 610 using a ball screw method. However, the power transmission method of the motor 620 is merely an example, and the technical concept of the present invention is not limited thereto.

[0090] The damper 630 can be arranged between the vertical force measuring unit 610 and the motor 620. The damper 630 can reduce the vibration generated during the period when the motor 620 provides power to the vertical force measuring unit 610.

[0091] Figure 2 and Figure 3 This is a flowchart illustrating a method for evaluating desorption force according to an embodiment of the present invention. Figures 4 to 7 This is a diagram illustrating intermediate steps of a desorption force evaluation method according to an embodiment of the present invention. Figure 8 It is used to explain in Figure 3 A graph showing the applied voltage state and the wafer lifting state during the intermediate steps of the desorption force evaluation method. Figure 9 It is used to explain in Figure 3 A graph showing the speed at which the vertical force measuring unit pulls the substrate during an intermediate step in the desorption force evaluation method.

[0092] For reference only. Figure 2 and Figure 3 The flowchart illustrates a method for evaluating the desorption force using a substrate testing apparatus according to some embodiments.

[0093] Reference Figure 2 The power supply to the substrate testing device can be turned on (S100). Since the substrate testing device is an electronic device that evaluates the desorption force by providing voltage and driving force, it may require a power supply.

[0094] Then, the substrate 100 can be initially set up (S200). Initial setting refers to evaluating the initial position, initial voltage, etc. in order to evaluate the desorption force of the substrate 100.

[0095] For example, the substrate 100 can be placed on the electrostatic chuck 220. The substrate 100 can be arranged between the electrostatic chuck 220 and the vertical force measuring unit 610.

[0096] As another example, see Figure 2 and Figure 4 A second grounding voltage GND2 can be applied to the substrate 100. Applying the second grounding voltage GND2 to the substrate 100 can remove residual charge remaining on the substrate 100. Therefore, an initial charge can be set on the substrate 100 before charging it.

[0097] When setting the initial charge on the substrate 100, the electrostatic chuck power application unit 300 may not apply the driving voltage HV and the first ground voltage GND1 to the electrostatic chuck 220.

[0098] Reference Figure 2 , Figure 3 , Figures 5 to 7 After initial setup of the substrate 100, the desorption force assessment of the electrostatic chuck 220 can be performed (S300).

[0099] The first step is to charge the substrate 100 (S310). To charge the substrate 100, a driving voltage HV can be applied to the electrostatic chuck 220. A second ground voltage GND2 can be applied to the substrate 100.

[0100] The driving voltage HV applied to the electrostatic chuck 220 can be approximately 2.73 kV. As the driving voltage HV is applied to the electrostatic chuck 220, the substrate 100 can become charged. A first residual charge C10 can accumulate on the lower surface of the substrate 100 adjacent to the electrostatic chuck 220.

[0101] Step S310, which charges the substrate 100, can be a simulation of the process of chucking the substrate 100 onto the electrostatic chuck 220 in a semiconductor processing technology.

[0102] The second step is to discharge the substrate 100 (S320). To discharge the substrate 100, a first ground voltage GND1 can be applied to the electrostatic chuck 220. A second ground voltage GND2 can be applied to the substrate 100.

[0103] As a first ground voltage GND1 is applied to the electrostatic chuck 220, the substrate 100 can be discharged. Specifically, the first residual charge C10 accumulated on the lower surface of the substrate 100 adjacent to the electrostatic chuck 220 can be dispersed. Therefore, a second residual charge C20, less than the first residual charge C10 in the charged state, can accumulate on the lower surface of the substrate 100.

[0104] Step S320, which discharges the substrate 100, can be a simulation of the process of discharging the substrate 100 in a semiconductor processing technology to dechucking the substrate 100 from the electrostatic chuck 220.

[0105] The third step is to desorb the substrate 100 (S330). To desorb the substrate 100, the driving voltage HV and the first ground voltage GND1 can be omitted from the electrostatic chuck 220. The second ground voltage GND2 can be omitted from the substrate 100.

[0106] Then, the vertical force measuring unit 610 can pull the substrate 100 in the vertical direction. Therefore, the substrate 100 can be separated from the electrostatic chuck 220 to achieve desorption.

[0107] After the substrate 100 is discharged, a second residual charge C20 may remain inside the substrate 100. Due to the second residual charge C20, an electrostatic attraction can be generated between the substrate 100 and the electrostatic chuck 220. Since no voltage is applied to the electrostatic chuck 220 and the substrate 100, the electrostatic attraction between the substrate 100 and the electrostatic chuck 220 caused by the second residual charge C20 remaining on the substrate 100 can be maintained.

[0108] At this time, by pulling the substrate 100 through the vertical force measuring unit 610, the electrostatic attraction can be measured. The electrostatic attraction can correspond to the desorption force F. That is, the desorption force F can be determined by the electrostatic attraction.

[0109] Reference Figure 3 and Figure 8 The step S310 of charging the substrate 100 can be performed until the first time t1.

[0110] For reference only. Figure 8 The horizontal axis in the diagram represents time. The vertical axis represents whether the electrostatic chuck 220 is subjected to a driving voltage HV and a first ground voltage GND1, whether the substrate 100 is subjected to a second ground voltage GND2, and whether the vertical force measuring unit 610 lifts the substrate 100 (LIFT UP).

[0111] Before the first time t1, the electrostatic chuck 220 is subjected to a drive voltage HV. The electrostatic chuck 220 is not subjected to a first ground voltage. The substrate 100 is subjected to a second ground voltage GND2.

[0112] The step S320 of discharging the substrate 100 can be performed from the first time t1 to the second time t2.

[0113] From the first time t1 to the second time t2, the electrostatic chuck 220 is not subjected to a drive voltage HV. The electrostatic chuck 220 is subjected to a first ground voltage GND1. The substrate 100 is subjected to a second ground voltage GND2.

[0114] The time required until the substrate 100 is charged at a first time t1 can be a first operating time (0 to t1). The time required from the substrate 100 being discharged at a first time t1 to a second time t2 can be a second operating time (t1 to t2). The first operating time (0 to t1) can be different from the second operating time (t1 to t2). Specifically, the first operating time (0 to t1) can be longer than the second operating time (t1 to t2).

[0115] After discharging the substrate 100, the substrate 100 can be lifted (LIFT UP) by the vertical force measuring unit 610 starting from the second time t2. In this case, the driving voltage HV is not applied to the electrostatic chuck 220. The first ground voltage GND1 is not applied to the electrostatic chuck 220. The second ground voltage GND2 is not applied to the substrate 100.

[0116] Reference Figure 3 and Figure 9 The desorption operation S330 on the substrate 100 can be performed after the second time t2.

[0117] For reference, Figure 9 In this diagram, the horizontal axis represents time, and the vertical axis represents velocity. Additionally, this diagram illustrates various lift-up velocities of the substrate 100 lifted by the vertical force measuring unit 610.

[0118] By supplying power to the vertical force measuring unit 610 via the motor 620, the vertical force measuring unit 610 can pull the substrate 100 at a uniform speed of either a first speed v1 or a second speed v2. The first speed v1 and the second speed v2 can be different.

[0119] For example, the first speed v1 can be slower than the second speed v2.

[0120] The vertical force measuring unit 610 is described as being able to pull the substrate 100 at two uniform speeds, but this is only an example, and the technical concept of the present invention is not limited thereto. For example, the vertical force measuring unit 610 can pull the substrate 100 at two or more uniform speeds.

[0121] After performing the desorption assessment of the electrostatic chuck 220 (S300), the measured desorption force F is confirmed (S400).

[0122] The greater the measured desorption force F, the greater the remaining electrostatic attraction between the substrate 100 and the electrostatic chuck 220. That is, it may mean that the desorption of the substrate 100 was not completely performed due to the large amount of residual charge on the substrate 100.

[0123] Next, the desorption force assessment is completed (S500).

[0124] Figure 10 This is a flowchart illustrating a method for evaluating desorption force according to an embodiment of the present invention. Figure 11 This is a diagram illustrating intermediate steps of a desorption force evaluation method according to an embodiment of the present invention. Figure 12 It is used to explain in Figure 10 A graph showing the applied voltage state and wafer lift-up state during intermediate steps of the desorption force evaluation method. For ease of description, brief descriptions or omissions will be made with reference to... Figures 2 to 8 The content described is repetitive.

[0125] For reference only. Figure 10 A flowchart is shown for a method of evaluating desorption force using a substrate testing apparatus according to some embodiments.

[0126] Reference Figure 10 and Figure 11 After charging the substrate 100 (S310) and before discharging the substrate 100 (S320), a step S315 may be included to put the substrate 100 into a waiting state.

[0127] In step S315, which puts the substrate 100 into a waiting state, the driving voltage HV and the first ground voltage GND1 may not be applied to the electrostatic chuck 220. The second ground voltage GND2 may not be applied to the substrate 100.

[0128] Since no voltage is applied to the electrostatic chuck 220 and the substrate 100, the substrate 100 can remain in a charged state. That is, the first residual charge C10 accumulated on the lower surface of the substrate 100 adjacent to the electrostatic chuck 220 can be retained.

[0129] The step S315 of putting the substrate 100 into a waiting state can have the following meaning: clearly distinguishing between the step S310 of charging the substrate 100 and the step S320 of discharging the substrate 100, so as to confirm the execution of the step S310 of charging the substrate 100 and the step S320 of discharging the substrate 100.

[0130] Reference Figure 12 The step of putting the substrate 100 into a standby state may be included between the step of charging the substrate 100 and the step of discharging the substrate 100.

[0131] The step of putting the substrate 100 into a waiting state can be performed from the first time t1 to the third time t3 after the substrate 100 is charged.

[0132] From the first time t1 to the third time t3, no driving voltage HV and the first ground voltage GND1 are applied to the electrostatic chuck 220. No second ground voltage GND2 is applied to the substrate 100.

[0133] The step S320 of discharging the substrate 100 can be performed from the third time t3 to the second time t2.

[0134] From the third time t3 to the second time t2, no driving voltage HV is applied to the electrostatic chuck 220. The electrostatic chuck 220 is subjected to a first ground voltage GND1. The substrate 100 is subjected to a second ground voltage GND2.

[0135] The time required from the first time t1 during which the substrate 100 is charged can be a first operating time (0 to t1). The time required from the third time t3 during which the substrate 100 is discharged to the second time t2 can be a second operating time (t3 to t2). The first operating time (0 to t1) can be different from the second operating time (t3 to t2). Specifically, the first operating time (0 to t1) can be longer than the second operating time (t3 to t2).

[0136] The time required for the substrate 100 to be kept in a charged state from the first time t1 to the third time t3 can be a third operation time (t1 to t3). The third operation time (t1 to t3) can be shorter than the first operation time (0 to t1) and the second operation time (t3 to t2).

[0137] The embodiments of the present invention have been described above with reference to the accompanying drawings. However, those skilled in the art should understand that the present invention can be implemented in other specific forms without changing its technical concept or essential features. Therefore, the above embodiments should be understood as exemplary in all respects, and not restrictive.

Claims

1. A substrate testing apparatus, comprising: An electrostatic chuck, with its supporting base plate; A vertical force measuring unit is arranged on the electrostatic chuck; The electrostatic chuck power application unit applies a driving voltage and a first grounding voltage to the electrostatic chuck; The substrate power application unit applies a second ground voltage to the substrate; A testing chamber, including an internal space for processing the substrate; An electric motor is located on the upper surface of the test chamber and provides power to the vertical force measuring unit to push or pull the substrate. as well as A damper is disposed between the motor and the vertical force measuring unit, and is used to reduce the vibration generated as the motor supplies power to the vertical force measuring unit. Specifically, the electrostatic chuck is charged by applying the driving voltage to the electrostatic chuck through the electrostatic chuck power application unit and applying the second ground voltage to the substrate through the substrate power application unit. The electrostatic chuck is charged with a first ground voltage by the electrostatic chuck power application unit, and the substrate is charged with a second ground voltage by the substrate power application unit. The substrate is then discharged. The desorption force of the substrate is measured by the vertical force measuring unit.

2. The substrate testing apparatus according to claim 1, wherein, Before the substrate is charged, the initial charge of the substrate is set by applying the second ground voltage to the substrate.

3. The substrate testing apparatus according to claim 2, wherein, When setting the initial charge of the substrate, the electrostatic chuck power application unit does not apply the driving voltage and the first grounding voltage to the electrostatic chuck.

4. The substrate testing apparatus according to claim 1, wherein, The substrate is charged for a first operating time, and The substrate is discharged for a second operating time that is different from the first operating time.

5. The substrate testing apparatus according to claim 1, wherein, After the substrate is charged and before the substrate is discharged, the driving voltage is not applied to the electrostatic chuck and the second ground voltage is not applied to the substrate, so that the substrate remains charged.

6. The substrate testing apparatus according to claim 5, wherein, The substrate is charged for a first operating time. The substrate is discharged for a second operating time shorter than the first operating time, and The substrate remains charged for a third operating time that is shorter than the second operating time.

7. The substrate testing apparatus according to claim 1, further comprising: A clamping element is arranged below the electrostatic chuck and is used to fix the electrostatic chuck.

8. The substrate testing apparatus according to claim 1, wherein, The measurement of the de-adhesion force of the substrate by the vertical force measuring unit is performed when the substrate is not subjected to the second ground voltage and the electrostatic chuck is not subjected to the driving voltage and the first ground voltage.

9. The substrate testing apparatus according to claim 1, wherein, After the substrate is discharged, residual charge remains inside the substrate. Electrostatic attraction is generated between the substrate and the electrostatic chuck through the residual charge, and The desorption force is determined based on the electrostatic attraction.

10. The substrate testing apparatus according to claim 1, further comprising: A conveyor unit is arranged below the test chamber and is used to transport the test chamber.

11. The substrate testing apparatus according to claim 10, in, The motor provides power to the vertical force measuring unit in a direction perpendicular to the substrate via a ball screw method.

12. The substrate testing apparatus according to claim 11, wherein, The motor provides power to the vertical force measuring unit, enabling the vertical force measuring unit to pull the substrate at a uniform speed of either a first speed or a second speed. The first speed is different from the second speed.

13. A method for measuring the desorption force using a substrate testing apparatus, comprising the following steps: Place the substrate on the electrostatic chuck; The substrate is charged by applying a driving voltage to the electrostatic chuck and a second grounding voltage to the substrate. Then, the substrate is discharged by applying a first ground voltage to the electrostatic chuck and a second ground voltage to the substrate; as well as Subsequently, the desorption force of the substrate is measured by pulling the substrate vertically using a vertical force measuring unit arranged on the substrate. The substrate testing apparatus includes: The electrostatic chuck is configured to support the substrate; The vertical force measuring unit is arranged on the electrostatic chuck; An electrostatic chuck power application unit is configured to apply the driving voltage and the first grounding voltage to the electrostatic chuck; A substrate power application unit is configured to apply the second ground voltage to the substrate; A testing chamber, including an internal space for processing the substrate; A motor is located on the upper surface of the test chamber and provides power to the vertical force measuring unit to push or pull the substrate; and A damper is arranged between the motor and the vertical force measuring unit and is used to reduce vibrations generated as the motor supplies power to the vertical force measuring unit.

14. The method for measuring desorption force according to claim 13, further comprising the following step before charging the substrate: The initial charge of the substrate is set by applying the second ground voltage to the substrate.

15. The method for measuring desorption force according to claim 14, wherein, When setting the initial charge of the substrate, neither the driving voltage nor the first grounding voltage is applied to the electrostatic chuck.

16. The method for measuring desorption force according to claim 13, further comprising the following steps after charging the substrate and before discharging the substrate: The substrate is kept charged by not applying the driving voltage to the electrostatic chuck and not applying the second ground voltage to the substrate.

17. The method for measuring desorption force according to claim 13, wherein, The step of measuring the de-adhesion force of the substrate by pulling the substrate vertically in the vertical direction by the vertical force measuring unit is performed without applying the driving voltage and the first ground voltage to the electrostatic chuck.

18. The method for measuring desorption force according to claim 13, wherein, After the substrate is discharged, residual charge remains inside the substrate. Electrostatic attraction is generated between the substrate and the electrostatic chuck through the residual charge, and The desorption force is determined based on the electrostatic attraction.

19. A substrate testing apparatus, comprising: An electrostatic chuck, with its supporting base plate; A vertical force measuring unit is arranged on the electrostatic chuck; The electrostatic chuck power application unit applies a driving voltage and a first grounding voltage to the electrostatic chuck; The substrate power application unit applies a second ground voltage to the substrate; A testing chamber, including an internal space for processing the substrate; An electric motor is located on the upper surface of the test chamber and provides power to the vertical force measuring unit to push or pull the substrate. as well as A damper is disposed between the motor and the vertical force measuring unit, and is used to reduce the vibration generated as the motor supplies power to the vertical force measuring unit. The electrostatic chuck is charged by applying the driving voltage to the electrostatic chuck through the electrostatic chuck power application unit and applying the second ground voltage to the substrate through the substrate power application unit. The first ground voltage is applied to the electrostatic chuck by the electrostatic chuck power application unit, and the second ground voltage is applied to the substrate by the substrate power application unit, causing the substrate to discharge. The desorption force of the substrate is measured by the vertical force measuring unit. The substrate is charged for a first operating time. The substrate is discharged for a second operating time that is different from the first operating time, and The measurement of the de-adhesion force of the substrate by the vertical force measuring unit is performed when the substrate is not subjected to the second ground voltage and the electrostatic chuck is not subjected to the driving voltage and the first ground voltage.

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