Electrostatic chuck inspection apparatus and method

Abstract

An electrostatic chuck inspection apparatus and method for non-destructive quality inspection of a DC electrode of an electrostatic chuck are provided. The electrostatic chuck inspection apparatus includes a measurement unit that measures a first capacitance with respect to a dielectric layer of an electrostatic chuck and measures a second capacitance with respect to an electrode disposed within the dielectric layer, and a control unit that evaluates a quality of the electrode based on the first capacitance and the second capacitance, wherein the electrostatic chuck is subjected to non-destructive quality inspection.

Description

Technical Field

[0001] This invention relates to an apparatus and method for inspecting electrostatic chucks. More specifically, it relates to an apparatus and method for inspecting DC electrodes disposed within the dielectric layer of an electrostatic chuck. Background Technology

[0002] Semiconductor device manufacturing processes can be executed continuously in semiconductor device manufacturing equipment and can be divided into front-end processes and back-end processes. Semiconductor manufacturing equipment can be set up in a space defined as a FAB (Fabrication Plant) to manufacture semiconductor devices.

[0003] Front-end processes refer to the processes of forming circuit patterns on a wafer to complete a chip. Front-end processes can include deposition processes (forming thin films on the wafer), photolithography processes (transferring photoresist onto the thin film using a photomask), etching processes (selectively removing unwanted areas using chemicals or reactive gases to form the desired circuit pattern on the wafer), ashing processes (removing residual photoresist after etching), ion implantation processes (implanting ions into areas connected to the circuit pattern to give it electronic component characteristics), and cleaning processes (removing contaminants from the wafer).

[0004] Post-processing refers to the processes used to evaluate the performance of products completed through pre-processing. Post-processing can include primary inspection processes that check the functionality of individual chips on a wafer to screen for good and bad products; packaging processes that cut and separate individual chips to give them the product shape through dicing, die bonding, wire bonding, molding, and marking; and final inspection processes that perform final checks on the characteristics and reliability of the product through electrical characteristic testing and burn-in testing. Summary of the Invention

[0005] When processing substrates (e.g., wafers) to manufacture semiconductor devices, an electrostatic chuck (ESC) can be used to fix the substrate in place.

[0006] In such an electrostatic chuck, the DC electrode can be the core factor determining the quality of substrate adsorption (i.e., wafer clamping), but because the DC electrode is inserted into the ceramic dielectric layer, it is difficult to perform maintenance.

[0007] The technical problem to be solved by the present invention is to provide an electrostatic chuck inspection device and method for performing non-destructive quality inspection of the DC electrode of an electrostatic chuck.

[0008] The technical problems of this invention are not limited to those described above. Those skilled in the art can clearly understand other technical problems not mentioned in the following description.

[0009] An aspect of the electrostatic chuck inspection apparatus of the present invention for solving the above-mentioned technical problems includes: a measurement unit for measuring a first capacitance for a dielectric layer of an electrostatic chuck and for measuring a second capacitance for an electrode disposed within the dielectric layer; and a control unit for evaluating the quality of the electrode based on the first capacitance and the second capacitance, wherein the electrostatic chuck inspection apparatus performs a non-destructive quality inspection on the electrostatic chuck.

[0010] The control unit can evaluate the quality of the electrode based on at least one of the electrode area and the electrode asymmetry.

[0011] When evaluating the quality of an electrode based on its area, the control unit can calculate the area of ​​the electrode and compare the calculated value with a reference value to evaluate the quality of the electrode.

[0012] The control unit can calculate the area of ​​the electrode based on the area of ​​the dielectric layer, the first capacitance, and the second capacitance.

[0013] When calculating the area of ​​the electrode, the control unit can also utilize the dielectric constant and the thickness of the dielectric layer.

[0014] The control unit can calculate the area of ​​the electrode by multiplying the value obtained by dividing the second capacitor by the first capacitor by the area of ​​the dielectric layer.

[0015] The reference value can be the area of ​​the region surrounded by the electrode.

[0016] When the calculated value equals the reference value, the control unit can determine that the electrode is of good quality; when the calculated value does not equal the reference value, the control unit can determine that the electrode is of poor quality.

[0017] When evaluating the quality of an electrode by taking into account both its area and its asymmetry, the control unit may first consider the area of ​​the electrode and then consider its asymmetry.

[0018] When the electrode is initially judged to be of good quality based on its area, the control unit may consider the asymmetry of the electrode to reassess its quality.

[0019] When evaluating the quality of an electrode based on its asymmetry, the control unit can divide the upper region of the dielectric layer into multiple smaller regions and evaluate the quality of the electrode using multiple third capacitances obtained by measuring each of the smaller regions.

[0020] The measuring unit can use a plate with metallic components to measure the plurality of third capacitors.

[0021] The size of the plate can correspond to the size of each of the small regions.

[0022] The control unit can compare the plurality of third capacitors to evaluate the quality of the electrodes.

[0023] When all the third capacitors are equal, the control unit can determine that the electrode is of good quality; when the third capacitors are not all equal, the control unit can determine that the electrode is of poor quality.

[0024] When the plurality of third capacitors are not all equal, the control unit can presume that the electrode moves asymmetrically to the side with the relatively larger third capacitor.

[0025] When measuring the first capacitance, the measuring unit can be connected to the upper part of the dielectric layer via a first wire connected to the first terminal, and can be connected to the lower part of the dielectric layer via a second wire connected to the second terminal.

[0026] When measuring the second capacitance, the measuring unit can be connected to the upper and lower parts of the dielectric layer via a first line and a second line connected to the first terminal, respectively, and can be connected to the transmission line connecting the electrode and the power supply via a third line connected to the second terminal.

[0027] Another aspect of the electrostatic chuck inspection apparatus of the present invention for solving the above-mentioned technical problems includes: a measurement unit for measuring a first capacitance for a dielectric layer of an electrostatic chuck and for measuring a second capacitance for an electrode disposed within the dielectric layer; and a control unit for evaluating the quality of the electrode based on the first capacitance and the second capacitance, wherein the control unit evaluates the quality of the electrode based on at least one of the area of ​​the electrode and the asymmetry of the electrode; when evaluating the quality of the electrode based on the area of ​​the electrode, the control unit calculates the area of ​​the electrode based on the area of ​​the dielectric layer, the first capacitance, and the second capacitance, and compares the calculated value with a reference value to evaluate the quality of the electrode; and when evaluating the quality of the electrode based on the asymmetry of the electrode, the control unit divides the upper region of the dielectric layer into a plurality of small regions and compares a plurality of third capacitances obtained by measuring for each of the small regions to evaluate the quality of the electrode.

[0028] An aspect of the electrostatic chuck inspection method of the present invention for solving the above-mentioned technical problems includes: a step of measuring a first capacitance for a dielectric layer of an electrostatic chuck; a step of measuring a second capacitance for an electrode disposed within the dielectric layer; and a step of evaluating the quality of the electrode based on the first capacitance and the second capacitance, wherein a non-destructive quality inspection is performed on the electrostatic chuck.

[0029] Specific details of other embodiments are included in the detailed description and accompanying drawings. Attached Figure Description

[0030] Figure 1 This is a schematic cross-sectional view showing the internal structure of a substrate processing apparatus according to one embodiment.

[0031] Figure 2 This is a schematic cross-sectional view showing the internal structure of a substrate processing apparatus according to another embodiment.

[0032] Figure 3 This is a schematic diagram illustrating the internal structure of an electrostatic chuck inspection device according to an embodiment of the present invention.

[0033] Figure 4 This is an example diagram illustrating a method for measuring the dielectric layer capacitance of a measuring unit constituting an inspection apparatus according to an embodiment of the present invention.

[0034] Figure 5 This is an example diagram illustrating an electrode capacitance measurement method for a measuring unit constituting an inspection apparatus according to an embodiment of the present invention.

[0035] Figure 6This is a first example diagram illustrating a method for checking the electrode area of ​​a control unit constituting an electrostatic chuck inspection apparatus according to an embodiment of the present invention.

[0036] Figure 7 This is a second example diagram illustrating a method for checking the electrode area of ​​a control unit constituting an electrostatic chuck inspection apparatus according to an embodiment of the present invention.

[0037] Figure 8 This is a third example diagram illustrating a method for checking the electrode area of ​​a control unit constituting an electrostatic chuck inspection apparatus according to an embodiment of the present invention.

[0038] Figure 9 This is a first example diagram illustrating a method for inspecting electrode asymmetry in a control unit constituting an electrostatic chuck inspection apparatus according to an embodiment of the present invention.

[0039] Figure 10 This is a second example diagram illustrating a method for checking electrode asymmetry in a control unit constituting an electrostatic chuck inspection apparatus according to an embodiment of the present invention.

[0040] Figure 11 This is a third example diagram illustrating a method for inspecting electrode asymmetry in a control unit constituting an electrostatic chuck inspection apparatus according to an embodiment of the present invention.

[0041] Explanation of reference numerals in the attached figures

[0042] 100: Substrate processing device; 110: Housing

[0043] 120: Substrate support unit; 121: Base

[0044] 122: Electrostatic chuck 123: Ring assembly

[0045] 124: Heating component; 125: Cooling component

[0046] 126: Cooling device; 130: Plasma generation unit

[0047] 131: Upper power supply; 132: First transmission line

[0048] 133: Lower power supply; 134: Second transmission line

[0049] 140: Nozzle unit; 150: First gas supply unit

[0050] 160: Second gas supply unit; 170: Lining unit

[0051] 180: Baffle unit; 190: Upper module

[0052] 210: Dielectric layer; 220: DC electrode

[0053] 300: Inspection device; 310: Measuring unit

[0054] 320: Control Unit; 331: First Line

[0055] 332: Second line; 333: Third line

[0056] 341: First terminal; 342: Second terminal

[0057] 410: Area of ​​the dielectric layer; 420: Area of ​​the DC electrode.

[0058] 510: Zone 1 520: Zone 2

[0059] 530: Third Zone 540: Fourth Zone

[0060] A: Capacitance of the first region B: Capacitance of the second region

[0061] C: Capacitance of the third region; D: Capacitance of the fourth region Detailed Implementation

[0062] Preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings. The advantages and features of the present invention, as well as methods for achieving these advantages and features, will be explained below with reference to the accompanying drawings. Figure 1 The invention becomes clear from the detailed description of the embodiments. However, the invention is not limited to the embodiments disclosed below, but can be implemented in many different forms. These embodiments are provided only to make the disclosure of the invention complete and to fully inform those skilled in the art of the scope of the invention, which is defined only by the scope of the claims. Throughout the specification, the same reference numerals refer to the same constituent elements.

[0063] When an element or layer is referred to as "on" or "above" another element or layer, it includes not only that it is directly above another element or layer, but also that other layers or elements are in between. Conversely, when an element is referred to as "directly" on or directly above another element, it indicates that there are no other elements or layers in between.

[0064] To readily describe the relationship between one element or component and another, as shown in the figure, spatial relative terms such as "below," "below," "lower," "above," and "upper" can be used. It should be understood that, in addition to the orientation shown in the figure, spatial relative terms also include terms indicating the different orientations of the elements during use or operation. For example, when the element shown in the figure is flipped, an element described as "below" or "below" of another element may be located "above" of that element. Therefore, the exemplary term "below" can include both "below" and "above" orientations. An element may also be oriented in another direction, thus allowing the spatial relative terms to be interpreted according to orientation.

[0065] Although the terms "first," "second," etc., are used to describe various elements, constituent elements, and / or parts, these elements, constituent elements, and / or parts are obviously not limited by these terms. These terms are only used to distinguish one element, constituent element, and / or part from another element, constituent element, and / or part. Therefore, the first element, first constituent element, or first part mentioned below can obviously also be a second element, second constituent element, or second part within the technical concept of the present invention.

[0066] The terminology used in this specification is for illustrative purposes and is not intended to limit the invention. In this specification, the singular form includes the plural form unless specifically stated otherwise. The terms "comprises" and / or "comprising" as used in this specification do not exclude the presence or addition of one or more other constituent elements, steps, operations, and / or components in addition to those mentioned.

[0067] Unless otherwise defined, all terms used in this specification (including technical and scientific terms) may be used in the sense that can be commonly understood by one of ordinary skill in the art to which this invention pertains. Furthermore, terms defined in commonly used dictionaries are not to be ideally or excessively interpreted unless explicitly defined otherwise.

[0068] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. When describing the invention with reference to the drawings, identical or corresponding constituent elements are given the same reference numerals, regardless of the reference numerals, and repeated descriptions thereof are omitted.

[0069] This invention relates to an electrostatic chuck inspection apparatus and method for performing non-destructive quality inspection of the DC electrode (i.e., ESC DC electrode) of an electrostatic chuck. First, a substrate processing apparatus equipped with an electrostatic chuck will be described.

[0070] Figure 1 This is a schematic cross-sectional view showing the internal structure of a substrate processing apparatus according to one embodiment.

[0071] according to Figure 1 The substrate processing apparatus 100 may include a housing 110, a substrate support unit 120, a plasma generation unit 130, a nozzle unit 140, a first gas supply unit 150, a second gas supply unit 160, a liner unit 170, a baffle unit 180, and an upper module 190.

[0072] The substrate processing apparatus 100 processes the substrate W (e.g., a wafer) using a dry etching process in a vacuum environment. The substrate processing apparatus 100 may, for example, use a plasma process to process the substrate W, and may be implemented as an etching process chamber, a cleaning process chamber, etc.

[0073] The housing 110 provides space for performing plasma processes. This housing 110 may have an exhaust port 111 at its lower part.

[0074] The vent 111 can be connected to the vent line 113, which is equipped with the pump 112. The vent 111 can discharge reaction byproducts generated during the plasma process and gases remaining inside the housing 110 to the outside of the housing 110 through the vent line 113. In this case, the internal space of the housing 110 can be depressurized to a predetermined pressure.

[0075] An opening 114 may be formed on the side wall of the housing 110. The opening 114 serves as a channel for the substrate W to enter and exit the interior of the housing 110. The opening 114 can be opened and closed by a door assembly 115.

[0076] The door assembly 115 may include an outer door 115a and a door actuator 115b. The outer door 115a is disposed on the outer wall of the housing 110. This outer door 115a can be moved in the vertical direction (i.e., the third direction 30) by the door actuator 115b. The door actuator 115b may be operated by a motor, hydraulic cylinder, pneumatic cylinder, etc.

[0077] A substrate support unit 120 is disposed in the lower inner region of the housing 110. This substrate support unit 120 can support the substrate W using electrostatic force. However, this embodiment is not limited to this. The substrate support unit 120 can also support the substrate W in various ways, such as mechanical clamping or vacuum.

[0078] When the substrate W is supported by electrostatic force, the substrate support unit 120 may include a base 121 and an electrostatic chuck (ESC) 122.

[0079] The electrostatic chuck 122 is a substrate support component that uses electrostatic force to support the substrate W placed on it. This electrostatic chuck 122 can be made of ceramic material and can be attached to the base 121 in a way that it is fixed to the base 121.

[0080] The electrostatic chuck 122 can also be configured to be movable in the vertical direction (i.e., the third direction 30) inside the housing 110 using a drive component (not shown). When the electrostatic chuck 122 is thus configured to be movable in the vertical direction, the substrate W can be positioned in an area exhibiting a more uniform plasma distribution.

[0081] The ring assembly 123 is configured to surround the edge of the electrostatic chuck 122. This ring assembly 123 can be configured in an annular shape and can support the edge region of the substrate W. The ring assembly 123 may include a focus ring 123a and an insulator ring 123b.

[0082] A focusing ring 123a is formed inside the insulating ring 123b and is positioned to surround the electrostatic chuck 122. This focusing ring 123a can be made of silicon and can concentrate ions generated in the plasma process onto the substrate W.

[0083] An insulator ring 123b is formed on the outside of the focusing ring 123a and is arranged to surround the focusing ring 123a. This insulator ring 123b can be made of quartz.

[0084] On the other hand, the ring assembly 123 may also include an edge ring (not shown) that is in close contact with the edge of the focusing ring 123a. The edge ring may be formed to prevent the side surface of the electrostatic chuck 122 from being damaged by plasma.

[0085] The first gas supply unit 150 supplies a first gas to remove foreign matter remaining on the upper part of the ring assembly 123 or the edge portion of the electrostatic chuck 122. This first gas supply unit 150 may include a first gas supply source 151 and a first gas supply line 152.

[0086] The first gas supply source 151 can supply nitrogen (N2 gas) as the first gas. However, this embodiment is not limited to this. The first gas supply source 151 can also supply other gases or cleaning agents.

[0087] The first gas supply line 152 is disposed between the electrostatic chuck 122 and the ring assembly 123. For example, the first gas supply line 152 can be connected between the electrostatic chuck 122 and the focusing ring 123a.

[0088] On the other hand, the first gas supply line 152 can also be disposed inside the focusing ring 123a and can be bent to connect between the electrostatic chuck 122 and the focusing ring 123a.

[0089] The heating element 124 and the cooling element 125 are configured to maintain the process temperature of the substrate W when an etching process is performed inside the housing 110. For this purpose, the heating element 124 may be a heating wire, and the cooling element 125 may be a cooling line through which the coolant flows.

[0090] The heating element 124 and the cooling element 125 can be disposed inside the substrate support unit 120 to maintain the process temperature of the substrate W. As an example, the heating element 124 can be disposed inside the electrostatic chuck 122, and the cooling element 125 can be disposed inside the base 121.

[0091] On the other hand, the cooling component 125 can receive coolant using the cooling device 126. The cooling device 126 can be disposed outside the housing 110.

[0092] The plasma generation unit 130 generates plasma from the gas remaining in the discharge space. Here, the discharge space refers to the space located above the substrate support unit 120 within the interior space of the housing 110.

[0093] The plasma generation unit 130 can generate plasma in the discharge space inside the housing 110 using an inductively coupled plasma (ICP) source. In this case, the plasma generation unit 130 can use the antenna unit 193 provided on the upper module 190 as the upper electrode and the electrostatic chuck 122 as the lower electrode.

[0094] However, this embodiment is not limited to this. The plasma generation unit 130 can also generate plasma in the discharge space inside the housing 110 using a capacitively coupled plasma (CCP) source. In this case, such as Figure 2 As shown, the plasma generation unit 130 can use the nozzle unit 140 as the upper electrode and the electrostatic chuck 122 as the lower electrode. Figure 2 This is a schematic cross-sectional view showing the internal structure of a substrate processing apparatus according to another embodiment.

[0095] Refer again Figure 1 Please provide an explanation.

[0096] The plasma generation unit 130 may include an upper electrode, a lower electrode, an upper power supply 131, and a lower power supply 133.

[0097] The upper power supply 131 applies power to the upper electrode, i.e., the antenna element 193. This upper power supply 131 can be configured to control the characteristics of the plasma. For example, the upper power supply 131 can be configured to adjust the ion bombardment energy.

[0098] Although Figure 1 A single upper power supply 131 is shown, but multiple upper power supplies 131 may also be provided in this embodiment. In the case of multiple upper power supplies 131, the substrate processing apparatus 100 may further include a first matching network (not shown) electrically connected to the multiple upper power supplies 131.

[0099] The first matching network can match different magnitudes of frequency power input from each upper power supply 131 and apply the matched power to the antenna element 193.

[0100] On the other hand, a first impedance matching circuit (not shown) may be provided on the first transmission line 132 connecting the upper power supply 131 and the antenna unit 193 for impedance matching.

[0101] The first impedance matching circuit can be used as a lossless passive circuit, so that electrical energy can be efficiently (i.e., maximally) transferred from the upper power supply 131 to the antenna element 193.

[0102] The lower power supply 133 applies power to the lower electrode, i.e., the electrostatic chuck 122. This lower power supply 133 can function as a plasma source to generate plasma, or it can function together with the upper power supply 131 to control the characteristics of the plasma.

[0103] Although Figure 1 A single lower power supply 133 is shown, but like the upper power supply 131, multiple lower power supplies 133 can also be provided in this embodiment. In the case of multiple lower power supplies 133, a second matching network (not shown) electrically connected to the multiple lower power supplies 133 may also be included.

[0104] The second matching network can match different magnitudes of frequency power input from each lower power source 133 and apply the matched power to the electrostatic chuck 122.

[0105] On the other hand, a second impedance matching circuit (not shown) may be provided on the second transmission line 134 connecting the lower power supply 133 and the electrostatic chuck 122 for impedance matching.

[0106] Similar to the first impedance matching circuit, the second impedance matching circuit can be used as a lossless passive circuit, allowing electrical energy to be efficiently (i.e., maximally) transferred from the lower power supply 133 to the electrostatic chuck 122.

[0107] The showhead unit 140 can be positioned inside the housing 110, vertically opposite the electrostatic chuck 122. This showhead unit 140 can have multiple gas feeding holes to inject gas into the housing 110, and can be configured to have a larger diameter than the electrostatic chuck 122. Alternatively, the showhead unit 140 can be made of silicon or metal.

[0108] The second gas supply unit 160 supplies process gas (second gas) to the interior of the housing 110 via the nozzle unit 140. This second gas supply unit 160 may include a second gas supply source 161 and a second gas supply line 162.

[0109] The second gas supply source 161 supplies cleaning gas as a process gas for processing the substrate W, the interior of the housing 110, etc. This second gas supply source 161 can also supply etching gas as a process gas for processing the substrate W.

[0110] The second gas supply source 161 can be a single source to supply process gas to the nozzle unit 140. However, this embodiment is not limited to this. Multiple second gas supply sources 161 can also be provided to supply process gas to the nozzle unit 140.

[0111] The second gas supply line 162 connects the second gas supply source 161 and the nozzle unit 140. The second gas supply line 162 delivers the process gas supplied by the second gas supply source 161 to the nozzle unit 140 so that the process gas flows into the interior of the housing 110.

[0112] On the other hand, when the nozzle unit 140 is divided into a center zone, a middle zone, an edge zone, etc., the second gas supply unit 160 may also include a gas distributor (not shown) and a gas distribution line (not shown) to supply process gas to each region of the nozzle unit 140.

[0113] The gas distributor distributes the process gas supplied from the second gas supply source 161 to various areas of the nozzle unit 140. This gas distributor can be connected to the second gas supply source 161 via the second gas supply line 162.

[0114] The gas distribution line connects the gas distributor and the various areas of the nozzle unit 140. The gas distribution line thereby delivers the process gas distributed by the gas distributor to the various areas of the nozzle unit 140.

[0115] Liner unit 170, also known as wall liner, is used to protect the inner surface of housing 110 from arc discharge generated during the ignition of process gases and impurities generated during substrate processing. This liner unit 170 can be configured as a cylindrical shape with open upper and lower sections inside housing 110.

[0116] The lining unit 170 may be configured to be adjacent to the inner wall of the housing 110. Such lining unit 170 may have a support ring 171 on its upper portion. The support ring 171 may be formed to protrude outward in the upper portion of the lining unit 170 in the direction of first direction 10, and may be placed at the upper end of the housing 110 to support the lining unit 170.

[0117] The baffle unit 180 serves to remove process byproducts and unreacted gases from the plasma. This baffle unit 180 can be disposed between the inner wall of the housing 110 and the substrate support unit 120.

[0118] The baffle unit 180 can be configured in an annular shape and can have multiple through holes extending in the vertical direction (i.e., the third direction 30). The baffle unit 180 can control the flow of process gas according to the number and shape of the through holes.

[0119] In this embodiment, the baffle unit 180 can be configured as two layers and can be driven to move up and down. The baffle unit 180 will be described in more detail later.

[0120] The upper module 190 is configured to cover the open upper portion of the housing 110. This upper module 190 may include a window component 191, an antenna component 192, and an antenna element 193.

[0121] Window component 191 is formed to cover the upper part of housing 110 to seal the internal space of housing 110. Such window component 191 may be configured as a plate (e.g., a circular plate) and may be formed of an insulating material (e.g., alumina (Al2O3)).

[0122] Window component 191 may include a dielectric window. Window component 191 may have a through-hole for inserting the second gas supply line 162 and may have a coating on its surface to suppress particle generation when performing plasma processes inside the housing 110.

[0123] Antenna component 192 is disposed above window component 191 and can provide a space of a predetermined size inside it so that antenna unit 193 can be arranged therein.

[0124] The antenna component 192 can be formed into a cylindrical shape with an open lower part, and can be configured to have a diameter corresponding to that of the housing 110. The antenna component 192 can be detachably mounted on the window component 191.

[0125] The antenna unit 193 serves as the upper electrode and is composed of coils arranged in a manner that forms a closed loop. This antenna unit 193 generates a magnetic field and an electric field inside the housing 110 based on the power supplied from the upper power source 131, thereby exciting the gas flowing into the housing 110 through the nozzle unit 140 into plasma.

[0126] Antenna element 193 may be constructed from a coil in the form of a planar spiral. However, this embodiment is not limited to this. The structure or size of the coil can be modified in various ways by those skilled in the art.

[0127] Next, an apparatus and method for performing non-destructive quality inspection on the DC electrode 220 of the electrostatic chuck 122 will be described.

[0128] The electrostatic chuck 122 can hold the substrate W in place when the substrate processing apparatus 100 processes the substrate (e.g., a wafer W). At this time, the DC electrode 220 can be inserted into the dielectric layer of the ceramic material constituting the electrostatic chuck 122 to interfere with the holding of the substrate W. That is, the DC electrode 220 can become a key factor determining the clamping quality of the substrate W.

[0129] However, as mentioned above, since the DC electrode 220 is inserted into the dielectric layer of the ceramic material, it is difficult to inspect and repair it. The following describes an apparatus and method for performing non-destructive quality inspection on the DC electrode 220 to solve this problem.

[0130] Figure 3 This is a schematic diagram illustrating the internal structure of an electrostatic chuck inspection device according to an embodiment of the present invention.

[0131] according to Figure 3 The inspection device 300 may include a measuring unit 310 and a control unit 320.

[0132] The inspection device 300 can perform non-destructive quality inspection on the DC electrode 220 of the electrostatic chuck 122 by capacitance measurement. Specifically, the inspection device 300 can perform non-destructive quality inspection on the DC electrode 220 using electrode area inspection methods, electrode asymmetry inspection methods, etc.

[0133] The measurement unit 310 measures capacitance. This measurement unit 310 can measure capacitance for the dielectric layer 210 of the electrostatic chuck 122, and can also measure capacitance for the DC electrode 220 disposed within the dielectric layer 210 of the electrostatic chuck 122.

[0134] In the case of measuring capacitance for dielectric layer 210, such as Figure 4 As shown, the measurement unit 310 can be connected to the upper and lower parts of the dielectric layer 210 via the first line 331 and the second line 332, respectively. In this case, the first line 331 can be connected to the first terminal 341 of the measurement unit 310, and the second line 332 can be connected to the second terminal 342 of the measurement unit 310. Figure 4 This is an example diagram illustrating a method for measuring the dielectric layer capacitance of a measuring unit constituting an inspection apparatus according to an embodiment of the present invention.

[0135] When measuring capacitance for DC electrode 220, such as Figure 5 As shown, the measurement unit 310 can be connected to the upper and lower parts of the dielectric layer 210 and the second transmission line 134 connecting the DC electrode 220 and the lower power supply 133 via the first line 331, the second line 332 and the third line 333, respectively. At this time, the first line 331 and the second line 332 can be connected to the first terminal 341 of the measurement unit 310, and the third line 333 can be connected to the second terminal 342 of the measurement unit 310. Figure 5 This is an example diagram illustrating an electrode capacitance measurement method for a measuring unit constituting an inspection apparatus according to an embodiment of the present invention.

[0136] Refer again Figure 3 Please provide an explanation.

[0137] The inspection device 300 has a single measurement unit 310, which can measure both the capacitance of the dielectric layer 210 and the capacitance of the DC electrode 220. The measurement unit 310 can first measure either the capacitance of the dielectric layer 210 or the capacitance of the DC electrode 220, and then measure the other capacitance.

[0138] However, this embodiment is not limited to this. The inspection device 300 may have two measurement units 310, and in this case, either measurement unit 310 can measure the capacitance of the dielectric layer 210, and the other measurement unit 310 can measure the capacitance of the DC electrode 220. When the inspection device 300 has two measurement units 310, the capacitance of the dielectric layer 210 and the capacitance of the DC electrode 220 can be measured simultaneously.

[0139] On the other hand, the measurement unit 310 can be implemented as an LCR tester capable of measuring inductance, capacitance, resistance, etc. The measurement unit 310 can also be implemented as an LCR meter.

[0140] The control unit 320 is used to evaluate the quality of the DC electrode 220. This control unit 320 can evaluate the quality of the DC electrode 220 based on the capacitance of the dielectric layer 210 and the capacitance of the DC electrode 220.

[0141] The control unit 320 can determine the quality of the DC electrode 220 using methods such as electrode area inspection and electrode asymmetry inspection. The electrode area inspection method and electrode asymmetry inspection method will be described in detail later.

[0142] The control unit 320 can be implemented as a computer or server including a process controller, a control program, an input module, an output module (or a display module), a memory module, etc. As described above, the process controller may include a microprocessor that performs control functions, and the control program may execute various processes according to the control of the process controller. The memory module may store programs, i.e., processing recipes, for performing various processes based on various data and processing conditions. Alternatively, the control unit 320 can also be implemented as a microprocessor.

[0143] Next, the method for checking the electrode area will be explained.

[0144] When manufacturing the electrostatic chuck 122, the thickness and dielectric constant of the upper dielectric layer 210 may deviate. Therefore, in this embodiment, in order to accurately calculate the area, the capacitance of the entire dielectric zone and the capacitance of the electrode zone can be measured sequentially, and the area ratio between the entire dielectric zone and the electrode zone can be calculated thereby.

[0145] The control unit 320 can calculate the area of ​​the DC electrode 220 based on the measurement results of the measurement unit 310. Specifically, the control unit 320 can calculate the area of ​​the DC electrode 220 based on the capacitance of the dielectric layer 210 and the capacitance of the DC electrode 220. The control unit 320 can use Equation 1 to calculate the area of ​​the DC electrode 220.

[0146] Equation 1

[0147]

[0148] Among them, A Electrode A represents the area of ​​DC electrode 220, i.e., the area of ​​the electrode region. Total This represents the area of ​​dielectric layer 210, i.e., the area of ​​the entire dielectric region. Furthermore, C... Electrode C represents the capacitance of DC electrode 220. Total This indicates the capacitance of dielectric layer 210.

[0149] On the other hand, since the dielectric layer 210 is exposed to the outside, its area can be measured in a non-destructive manner. The area of ​​the dielectric layer 210 can be measured in advance, but it can also be measured when the measurement unit 310 measures the capacitance of the dielectric layer 210 and the capacitance of the DC electrode 220.

[0150] On the other hand, Equation 1 above can be calculated sequentially from Equations 2 to 5.

[0151] Equation 2

[0152]

[0153] Where ε represents the dielectric constant of dielectric layer 210, and D represents the thickness of dielectric layer 210.

[0154] Equation 3

[0155]

[0156] Equation 4

[0157]

[0158] [Equation 5]

[0159]

[0160] When the area of ​​DC electrode 220 is calculated using Equation 1, the control unit 320 can compare the calculated value with a reference value to determine the quality of DC electrode 220. Here, the reference value is the specification (Spec) used when manufacturing the electrostatic chuck 122, which can be pre-stored in the memory module of the control unit 320. The reference value can be the area of ​​the region surrounded by DC electrode 220 during the manufacturing of electrostatic chuck 122.

[0161] When the calculated value (i.e., the area of ​​DC electrode 220 calculated by Equation 1) equals the reference value, such as Figure 6As shown, the area 420 of the DC electrode 220 relative to the area 410 of the dielectric layer 210 corresponds to the position of the DC electrode 220 disposed within the dielectric layer 210. Therefore, the control unit 320 can determine that the DC electrode 220 is of good quality. Figure 6 This is a first example diagram illustrating a method for checking the electrode area of ​​a control unit constituting an electrostatic chuck inspection apparatus according to an embodiment of the present invention.

[0162] Conversely, when the calculated value is not equal to the reference value, the control unit 320 can determine that the DC electrode 220 is defective. For example, when the calculated value is less than the reference value, such as... Figure 7 As shown, the area 420 of the DC electrode 220 relative to the area 410 of the dielectric layer 210 is located inside the position of the DC electrode 220 disposed within the dielectric layer 210. In this case, due to the reduction in wafer clamping force, He leakage may occur, so the control unit 320 can determine that the DC electrode 220 is of poor quality. Figure 7 This is a second example diagram illustrating a method for checking the electrode area of ​​a control unit constituting an electrostatic chuck inspection apparatus according to an embodiment of the present invention.

[0163] On the other hand, when the calculated value is greater than the baseline value, such as Figure 8 As shown, the area 420 of the DC electrode 220 relative to the area 410 of the dielectric layer 210 may extend beyond the position of the DC electrode 220 disposed within the dielectric layer 210. In this case, due to the increased wafer clamping force, wafer detachment defects may occur, and the control unit 320 can determine that the DC electrode 220 is of poor quality. Figure 8 This is a third example diagram illustrating a method for checking the electrode area of ​​a control unit constituting an electrostatic chuck inspection apparatus according to an embodiment of the present invention.

[0164] On the other hand, even if the calculated value equals the baseline value, such as Figure 9 As shown, the area 420 of the DC electrode 220 relative to the area 410 of the dielectric layer 210 may not correspond to the position of the DC electrode 220 disposed within the dielectric layer 210. That is, electrode asymmetry may occur. In this case, He leakage may occur due to uneven wafer clamping force.

[0165] In this embodiment, considering the above-mentioned problems, the control unit 320 can use an electrode asymmetry inspection method to check the quality of the DC electrode 220. Figure 9 This is a first example diagram illustrating a method for inspecting electrode asymmetry in a control unit constituting an electrostatic chuck inspection apparatus according to an embodiment of the present invention.

[0166] Next, the method for checking electrode asymmetry will be explained.

[0167] The measurement unit 310 can divide the edge region of the dielectric layer 210 into multiple local regions and measure the capacitance for each local region. At this time, the measurement unit 310 can use a metallic plate (i.e., a metallic plate having an area that can be measured only for local areas of the ESC edge region) to measure the capacitance for local regions of the dielectric layer 210.

[0168] The metallic plate can be a flat metal plate and can have a size corresponding to a local area of ​​the dielectric layer 210. That is, when measuring the capacitance for each local area of ​​the dielectric layer 210, the metallic plate can contact the corresponding local area of ​​the dielectric layer 210, and the measurement unit 310 can be connected to the metallic plate via the first line 331 and to the lower part of the dielectric layer 210 via the second line 332, thereby enabling the measurement of capacitance for the corresponding local area of ​​the dielectric layer 210.

[0169] The control unit 320 can compare the capacitance of multiple local regions to determine the quality of the DC electrode 220. Here, the multiple local regions can have the same size.

[0170] The following will use the case where the edge region of dielectric layer 210 is divided into four regions as an example to illustrate the method for judging the quality of DC electrode 220.

[0171] Figure 10 This is a second example diagram illustrating a method for checking electrode asymmetry in a control unit constituting an electrostatic chuck inspection apparatus according to an embodiment of the present invention. Figure 11 This is a third example diagram illustrating a method for inspecting electrode asymmetry in a control unit constituting an electrostatic chuck inspection apparatus according to an embodiment of the present invention.

[0172] The measurement unit 310 measures the capacitance of the first region 510, the second region 520, the third region 530 and the fourth region 540. At this time, the capacitance of the first region 510, the capacitance of the second region 520, the capacitance of the third region 530 and the capacitance of the fourth region 540 are defined as A, B, C and D, respectively.

[0173] like Figure 6 As shown, with symmetrical electrodes, the capacitance of each local region will be the same. Therefore, as Figure 10 As shown, the capacitances A, B, C, and D of the four regions 510, 520, 530, and 540 are all equal (A = B = C = D). Therefore, under these circumstances, the control unit 320 can determine that the DC electrode 220 is of good quality.

[0174] On the contrary, such as Figure 9As shown, when the electrodes are asymmetrical, there will be a deviation in the capacitance between the various local areas. Therefore, the capacitances A, B, C, and D of the four areas 510, 520, 530, and 540 are not all equal. In this case, the control unit 320 can determine that the DC electrode 220 is of poor quality.

[0175] On the other hand, in the case of electrode asymmetry, when a capacitance deviation occurs, it can be presumed that the electrodes have asymmetrically moved to positions with higher values. For example, such as... Figure 11 As shown, when the capacitance D of the fourth region 540 is relatively maximum and the capacitance B of the second region 520 is relatively minimum (D>A=C>B), the control unit 320 can be presumed to have the electrodes moved asymmetrically in the direction of the fourth region 540.

[0176] Reference above Figures 1 to 11 An electrostatic chuck inspection apparatus 300 and method according to an embodiment of the present invention are described. The present invention relates to a non-destructive quality inspection apparatus and method for ESC DC electrodes 220, which can confirm the size and asymmetry of DC electrodes 220 by capacitance measurement.

[0177] In the case of the electrode area inspection method, the quality of the DC electrode 220 can be determined by measuring the capacitance of the entire ESC dielectric region, the capacitance of the DC electrode region, and the dielectric area, and by using the measured results to derive the area of ​​the DC electrode inserted into the ESC dielectric.

[0178] Furthermore, in the case of the electrode asymmetry inspection method, the quality of the DC electrode 220 can be determined by measuring the capacitance at different locations using a metal plate with an area that can be measured only locally in the ESC edge region and comparing the magnitude of the measured results. In the case of symmetrical electrodes, the capacitance of each region is the same; however, in the case of asymmetrical electrodes, a capacitance value deviation occurs, and it can be inferred that the electrode has asymmetrically moved to a position with a higher value.

[0179] 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, it should be understood that the embodiments described above are exemplary in all respects and not restrictive.

Claims

1. An electrostatic chuck inspection device, comprising: The measurement unit measures a first capacitance for the dielectric layer of the electrostatic chuck and a second capacitance for the electrodes disposed within the dielectric layer. as well as The control unit evaluates the quality of the electrode based on the first capacitor and the second capacitor. The electrostatic chuck inspection device performs non-destructive quality inspection on the electrostatic chuck. The control unit evaluates the quality of the electrode based on at least one of the area of ​​the electrode and the asymmetry of the electrode. In the case of evaluating the quality of the electrode based on its area, the control unit calculates the area of ​​the electrode based on the area of ​​the dielectric layer, the first capacitance, and the second capacitance, and compares the calculated value with a reference value to evaluate the quality of the electrode.

2. The electrostatic chuck inspection device according to claim 1, wherein, When calculating the area of ​​the electrode, the control unit also utilizes the dielectric constant and the thickness of the dielectric layer.

3. The electrostatic chuck inspection device according to claim 1, wherein, The control unit calculates the area of ​​the electrode by multiplying the value obtained by dividing the second capacitor by the first capacitor by the area of ​​the dielectric layer.

4. The electrostatic chuck inspection device according to claim 1, wherein, The reference value is the area of ​​the region surrounded by the electrode.

5. The electrostatic chuck inspection device according to claim 1, wherein, When the calculated value equals the reference value, the control unit determines that the electrode is of good quality; when the calculated value does not equal the reference value, the control unit determines that the electrode is of poor quality.

6. The electrostatic chuck inspection device according to claim 1, wherein, When evaluating the quality of an electrode by taking into account both its area and its asymmetry, the control unit first considers the area of ​​the electrode and then considers its asymmetry.

7. The electrostatic chuck inspection device according to claim 6, wherein, When the electrode is initially judged to be of good quality based on its area, the control unit considers the asymmetry of the electrode to reassess its quality.

8. The electrostatic chuck inspection device according to claim 1, wherein, When evaluating the quality of an electrode based on its asymmetry, the control unit divides the upper region of the dielectric layer into multiple smaller regions and evaluates the quality of the electrode using multiple third capacitances obtained by measuring each of the smaller regions.

9. The electrostatic chuck inspection device according to claim 8, wherein, The measuring unit uses a plate with metallic components to measure the plurality of third capacitors.

10. The electrostatic chuck inspection device according to claim 9, wherein, The size of the plate corresponds to the size of each of the small regions.

11. The electrostatic chuck inspection device according to claim 8, wherein, The control unit compares the plurality of third capacitors with each other to evaluate the quality of the electrodes.

12. The electrostatic chuck inspection device according to claim 11, wherein, When all the third capacitors are equal, the control unit determines that the electrode is of good quality; when the third capacitors are not all equal, the control unit determines that the electrode is of poor quality.

13. The electrostatic chuck inspection device according to claim 12, wherein, If the plurality of third capacitors are not all equal, the control unit presumes that the electrode moves asymmetrically to the side with the relatively larger third capacitor.

14. The electrostatic chuck inspection device according to claim 1, wherein, When measuring the first capacitance, the measuring unit is connected to the upper part of the dielectric layer via a first wire connected to the first terminal, and to the lower part of the dielectric layer via a second wire connected to the second terminal.

15. The electrostatic chuck inspection device according to claim 1, wherein, When measuring the second capacitance, the measuring unit is connected to the upper and lower parts of the dielectric layer via a first line and a second line connected to the first terminal, respectively, and is connected to the transmission line connecting the electrode and the power supply via a third line connected to the second terminal.

16. An electrostatic chuck inspection device, comprising: The measurement unit measures a first capacitance for the dielectric layer of the electrostatic chuck and a second capacitance for the electrodes disposed within the dielectric layer. as well as The control unit evaluates the quality of the electrode based on the first capacitor and the second capacitor. The control unit evaluates the quality of the electrode based on at least one of the electrode's area and the electrode's asymmetry. In evaluating the quality of an electrode based on its area, the control unit calculates the area of ​​the electrode based on the area of ​​the dielectric layer, the first capacitance, and the second capacitance, and compares the calculated value with a reference value to evaluate the quality of the electrode. When evaluating the quality of an electrode based on its asymmetry, the control unit divides the upper region of the dielectric layer into multiple smaller regions and compares multiple third capacitances obtained by measuring each of the smaller regions to evaluate the quality of the electrode.

17. A method for inspecting an electrostatic chuck, comprising: The steps for measuring the first capacitance of the dielectric layer of an electrostatic chuck; The step of measuring the second capacitance with respect to an electrode disposed within the dielectric layer; The steps for evaluating the quality of the electrode based on the first capacitor and the second capacitor. The step of evaluating the quality of the electrode based on at least one of the area of ​​the electrode and the asymmetry of the electrode; as well as In evaluating the quality of an electrode based on its area, the steps include calculating the area of ​​the electrode based on the area of ​​the dielectric layer, the first capacitance, and the second capacitance, and comparing the calculated value with a reference value to evaluate the quality of the electrode. The electrostatic chuck is subjected to non-destructive quality inspection.

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