Cleaning apparatus for electrostatic chuck and cleaning method using the same

Abstract

According to one embodiment of the present invention, a cleaning method for an electrostatic chuck and a cleaning device for an electrostatic chuck are provided, characterized by comprising the steps of supplying a solvent to a porous filter of an electrostatic chuck, generating ultrasound to a porous filter supplied with a solvent, and supplying cleaning water to a porous filter and cleaning the porous filter.

Description

Technology Field

[0001] The present invention relates to a cleaning method for an electrostatic chuck and a cleaning device for an electrostatic chuck using the same.

[0002] More specifically, the invention relates to a cleaning method for an electrostatic chuck and a cleaning device using the same, which can prevent clogging of the porous filter and damage to the product during the overhaul process. Background Technology

[0003] Generally, semiconductor devices can be manufactured by sequentially or repeatedly performing numerous processes such as sputtering, photolithography, etching, ion implantation, and chemical vapor deposition on a wafer placed in a chamber.

[0004] In the manufacturing process of such semiconductor devices, it is important that the wafer is tightly secured within the chamber to maintain uniform thin film characteristics.

[0005] Meanwhile, regarding wafer fixation methods, there are mechanical chuck and electrostatic chuck (ESC) methods; however, the electrostatic chuck method is widely used because it generates even attractive or repulsive forces across the entire contact surface with the wafer to ensure surface flatness and allows for effective temperature control by ensuring close contact between the wafer and the contact surface.

[0006] Conventional electrostatic chucks are equipped with a porous filter in the gas path to supply gas to a wafer mounted on the surface in order to suppress arcing in the gas path; however, there was a problem in that the inside of the porous filter became clogged due to polymer contamination or other factors during continuous use of the electrostatic chuck. The problem to be solved

[0007] The present invention provides a cleaning method for an electrostatic chuck and a cleaning device using the same, which includes a cleaning process comprising supplying a solvent, generating ultrasound, and supplying cleaning water, thereby enabling effective cleaning of a porous filter without separating the adsorption plate, preventing clogging of the porous filter by contaminants, and preventing product damage to the adsorption plate during the overhaul process. means of solving the problem

[0008] According to one embodiment of the present invention, a method for cleaning an electrostatic chuck is provided, comprising: a step of supplying a solvent to a porous filter of an electrostatic chuck; a step of generating ultrasound to the porous filter to which the solvent has been supplied; and a step of supplying cleaning water to the porous filter and cleaning the porous filter.

[0009] In the cleaning method of the electrostatic chuck described above, the electrostatic chuck comprises: a base body; an adsorption plate disposed facing the base body; and a porous filter disposed between the base body and the adsorption plate; and the step of supplying the solvent may supply the solvent to the porous filter through a plate hole portion formed in the adsorption plate and a supply channel formed in the base body.

[0010] In the cleaning method of the electrostatic chuck described above, the step of generating ultrasound can transmit ultrasonic vibrations to the porous filter through the solvent located in the plate hole portion.

[0011] In the cleaning method of the electrostatic chuck described above, the step of cleaning the porous filter may include: a step of supplying cleaning water to the porous filter; and a step of supplying a fluid gas to the porous filter.

[0012] In the cleaning method of the electrostatic chuck described above, the solvent may include at least one of diethyleneglycol-monoethylether, diethyleneglycol-monoethylether acetate, and an acidic substance.

[0013] According to one embodiment of the present invention, a cleaning device for an electrostatic chuck is provided, characterized by comprising: a solvent supply unit for supplying a solvent to a porous filter provided in an electrostatic chuck; an ultrasonic generator for generating ultrasonic waves to the porous filter to which the solvent is supplied; and a filter cleaning unit for supplying cleaning water to one side of the porous filter, discharging cleaning water from the other side of the porous filter, and cleaning the porous filter.

[0014] The cleaning device for the electrostatic chuck described above may further include: a gas supply unit that supplies fluid gas to the porous filter; and a flow sensor unit that detects the amount of fluid gas supplied from the gas supply unit and passing through the porous filter. Effects of the invention

[0015] A cleaning method for an electrostatic chuck according to one embodiment of the present invention performs a cleaning process consisting of supplying a solvent, generating ultrasound, and supplying cleaning water without the need to separate the adsorption plate of the electrostatic chuck from the base body, thereby preventing clogging of the porous filter by contaminants during use of the electrostatic chuck and thereby preventing damage to the product (e.g., the adsorption plate) during the overhaul process.

[0016] In addition, the cleaning effect can be enhanced by supplying cleaning water and fluid gas to the porous filter, and the cleaning process of the porous filter can be operated efficiently by monitoring the flow rate of the fluid gas passing through the porous filter.

[0017] In addition, by providing a cleaning process that includes solvent supply, ultrasonic generation, and cleaning water supply, it does not require a high level of technical expertise to perform the process and eliminates the need to risk product damage during the overhaul, thereby effectively reducing process costs and time compared to conventional overhaul processes. Brief explanation of the drawing

[0018] FIG. 1 is a block diagram illustrating a cleaning device for an electrostatic chuck according to one embodiment of the present invention. FIG. 2 is a cross-sectional view illustrating an electrostatic chuck to which a cleaning device for an electrostatic chuck according to one embodiment of the present invention is applied. Figure 3 is a series of cross-sectional views illustrating the process of manufacturing the electrostatic chuck of Figure 2. FIG. 4 is a drawing showing a state in which a solvent supply unit according to one embodiment of the present invention is provided in an electrostatic chuck. FIG. 5 is a diagram illustrating a state in which an ultrasonic generating unit according to one embodiment of the present invention is provided in an electrostatic chuck. FIG. 6 is a drawing illustrating a state in which a filter cleaning unit and a gas supply unit according to one embodiment of the present invention are provided in an electrostatic chuck. FIG. 7 is a drawing showing a state in which a filter cleaning unit and a gas supply unit according to another embodiment of the present invention are provided in an electrostatic chuck. FIG. 8 is a flowchart illustrating a cleaning method for an electrostatic chuck using a cleaning device for an electrostatic chuck according to one embodiment of the present invention. Specific details for implementing the invention

[0019] The present invention will be described in more detail below with reference to the drawings.

[0020] The suffixes "module" and "part" for components used in the following description are assigned solely for the ease of drafting this specification and do not inherently confer any particularly significant meaning or role. Accordingly, the terms "module" and "part" may be used interchangeably.

[0021] Terms including ordinal numbers, such as first, second, etc., may be used to describe various components, but said components are not limited by said terms. These terms are used solely for the purpose of distinguishing one component from another.

[0022] In this application, terms such as “comprising” or “having” are intended to specify the existence of the features, numbers, steps, actions, components, parts, or combinations thereof described in the specification, and should be understood as not precluding the existence or addition of one or more other features, numbers, steps, actions, components, parts, or combinations thereof.

[0023] Hereinafter, a cleaning device for an electrostatic chuck and a cleaning method for an electrostatic chuck according to one embodiment of the present invention will be described in detail with reference to the attached drawings.

[0024] FIG. 1 is a block diagram illustrating a cleaning device for an electrostatic chuck according to one embodiment of the present invention. FIG. 2 is a cross-sectional view illustrating an electrostatic chuck to which the cleaning device for an electrostatic chuck according to one embodiment of the present invention is applied. FIG. 3 is a cross-sectional view illustrating the process of manufacturing the electrostatic chuck of FIG. 2. FIG. 4 is a diagram illustrating a state in which a solvent supply unit according to one embodiment of the present invention is provided in an electrostatic chuck. FIG. 5 is a diagram illustrating a state in which an ultrasonic generator according to one embodiment of the present invention is provided in an electrostatic chuck. FIG. 6 is a diagram illustrating a state in which a filter cleaning unit and a gas supply unit according to one embodiment of the present invention are provided in an electrostatic chuck. FIG. 7 is a diagram illustrating a state in which a filter cleaning unit and a gas supply unit according to another embodiment of the present invention are provided in an electrostatic chuck.

[0025] Referring to FIGS. 1, FIGS. 2, FIGS. 4 to 6, a cleaning device for an electrostatic chuck (hereinafter referred to as the "cleaning device") (100) according to one embodiment of the present invention cleans a porous filter (220) provided on an electrostatic chuck (200), and may include a solvent supply unit (110), an ultrasonic generator (120), a filter cleaning unit (130-1), and a gas supply unit (130-2).

[0026] Before describing the cleaning device (100) according to one embodiment of the present invention, we will describe in detail the electrostatic chuck (200) to which the cleaning device (100) is applied.

[0027] Referring to FIGS. 2 and 3, an electrostatic chuck (200) according to one embodiment of the present invention may include a base body (210), a porous filter (220), an adhesive layer (230), and an adsorption plate (240).

[0028] The electrostatic chuck (200) can be formed by bonding the base body (210), the adhesive layer (230), and the adsorption plate (240) so that they are sequentially stacked.

[0029] Referring to FIGS. 2, FIGS. 3, and FIGS. 6, a base body (210) according to one embodiment of the present invention may be accommodated inside a chamber (133) in which a supply channel (211) through which gas (G) can flow is formed.

[0030] A base body (210) according to one embodiment of the present invention can function as a support for installing an adsorption plate (240). The base body (210) may be formed in the shape of a flat disc, and at least one through hole (not shown in the drawing) into which an electrode part (not shown in the drawing) for applying power to the adsorption plate (240) is inserted may be formed.

[0031] As an optional embodiment, a heater plate (not shown in the drawing) may be disposed between the base body (210) and the adsorption plate (240). As a means for controlling the temperature of the electrostatic chuck (200), a heater pattern may be printed on the inside or bottom surface of the heater plate.

[0032] The heater pattern can be composed of an electric resistive element and can generate heat by a current applied from an external power source.

[0033] For example, the heater pattern may be formed of molybdenum (Mo), stainless steel (SUS), nickel-chromium (Ni-Cr) alloy, tungsten (W), preferably Inconel, but is not limited thereto.

[0034] The heat generated from the heater plate can be used to control the temperature of the gas and / or wafer (W) in a high-density plasma process.

[0035] As an optional embodiment, the heater plate may be formed in a flat disc shape, similar to the base body (210).

[0036] The heater plate can be manufactured with a thickness of 20T for ease of processing, and after being joined to the base body (210), it can be cut and polished to a thickness of 1T.

[0037] As an optional embodiment, the heater plate may be separate or integral, and a heater electrode connected to a heater pattern (not shown in the drawing) may be connected to the heater plate. Additionally, at least one through hole may be formed in the heater plate through which an electrode portion (not shown in the drawing) for applying power to the adsorption plate (240) communicates.

[0038] As an optional embodiment, a cooling means (not shown in the drawing) for cooling a wafer (W) placed on the upper surface of an adsorption plate (240) may be further provided on the outside or inside of the base body (210).

[0039] Referring to FIG. 2, a supply channel (211) may be formed in a base body (210) according to one embodiment of the present invention.

[0040] The supply channel (211) connects the inside and outside of the base body (210), and can receive an inert gas (G), specifically helium (He) gas, from the outside and can reach a wafer (W) placed on the upper surface of the adsorption plate (240) through a plate hole portion (242) formed in the adsorption plate (240).

[0041] As a result, the wafer (W) is placed on the adsorption plate (240), and the wafer (W) can be cooled with an inert gas (G), such as helium gas, while numerous processes such as sputtering, photolithography, etching, ion implantation, and chemical vapor deposition are performed sequentially or repeatedly.

[0042] Referring to FIGS. 2 and FIGS. 3, a base body (210) according to one embodiment of the present invention may have a different outer diameter along the height direction (up and down direction based on FIG. 2). Specifically, the lower region of the base body (210) may have a relatively larger outer diameter compared to the upper region (based on FIG. 2).

[0043] As a result, the lower region of the base body (210), which has a relatively large area, is positioned in contact with the ground where the electrostatic chuck (200) is installed, thereby having the effect of stably supporting the upper region of the base body (210) where the wafer (W) is placed.

[0044] Referring to FIG. 2 and FIG. 3, in a base body (210) according to one embodiment of the present invention, an insertion groove (210a) may be formed so that a porous filter (220), specifically a lower filter (221), can be inserted, and the insertion groove (210a) may be formed in the shape of a groove.

[0045] An insertion groove (210a) formed in a base body (210) according to one embodiment of the present invention is connected to a supply channel (211), and a lower filter (221) is inserted and disposed in the insertion groove (210a), so that gas (G) supplied from the outside through the supply channel (211) can pass through the lower filter (221).

[0046] Referring to FIG. 2 and FIG. 3, the adsorption plate (240) to be described later may have a filter groove (240a) formed therein so that a porous filter (220), specifically an upper filter (222), can be inserted therein, and the filter groove (240a) may be formed in the shape of a groove.

[0047] The insertion groove (210a) formed in the base body (210) can be positioned facing each other with the filter groove (240a) formed in the adsorption plate (240) and can share a center.

[0048] A filter groove (240a) formed in an adsorption plate (240) according to one embodiment of the present invention is connected to a plate hole (242), and as an upper filter (222) is inserted and disposed in the filter groove (240a), gas (G) passing through the upper filter (222) can be supplied to a wafer (W) through the plate hole (242).

[0049] Referring to FIG. 2 and FIG. 3, an electrostatic chuck (200) according to one embodiment of the present invention may be formed such that a lower filter (221) is provided on a base body (210) and an upper filter (222) is provided on an adsorption plate (240) separately from the base body (210), and the lower surface of the adsorption plate (240) is bonded to the upper surface of the base body (210) through an adhesive layer (230).

[0050] Specifically, a lower filter (221) can be inserted and coupled into the insertion groove (210a) of the base body (210), and an upper filter (222) can be inserted and coupled into the filter groove (240a) of the adsorption plate (240). In a state where an adhesive layer (230) is provided on the upper surface of the base body (210) excluding the upper surface of the lower filter (221), the adsorption plate (240) having the upper filter (222) provided on the upper surface of the base body (210) can be bonded through the adhesive layer (230).

[0051] An adhesive layer (230) according to one embodiment of the present invention is disposed between a base body (210) and an adsorption plate (240), and can connect the base body (210) and the adsorption plate (240).

[0052] Referring to FIG. 2 and FIG. 3, an adhesive layer (230) according to one embodiment of the present invention may include an adhesive dam portion (231) and an adhesive portion (232).

[0053] The adhesive dam portion (231) is positioned on the base body (210) while surrounding the insertion groove portion (210a) formed in the base body (210), and specifically, it can be positioned while surrounding the upper surface edge of the lower filter (221).

[0054] The adhesive dam (231) can be formed from an insulating material having adhesive properties and can be formed by applying and curing on the base body (210). The adhesive dam (231) is positioned inside the adhesive part (232) to be described later, and can be formed before the adhesive part (232).

[0055] The adhesive dam (231) can be formed from an insulating material having adhesive properties and can be formed by applying and curing on the base body (210). The adhesive dam (231) is positioned inside the adhesive part (232) to be described later, and can be formed before the adhesive part (232).

[0056] Since the adhesive dam portion (231) is formed before the adhesive portion (232), the adhesive portion (232) can be blocked from entering the upper surface of the lower filter (221) during the process of the adhesive portion (232) being applied and cured on the base body (210).

[0057] Looking at this from another perspective, the adhesive dam part (231) can function as a dam by having a solid nature compared to the adhesive part (232).

[0058] For example, the adhesive dam portion (231) may be a gel-type silicone adhesive with lower fluidity than the adhesive portion (232), and the adhesive portion (232) may be provided on the upper surface of the base body (210) while the adhesive dam portion (231) is provided to surround the upper surface edge of the lower filter (221).

[0059] As a result, when an adhesive portion (232) is provided on the upper surface of the base body (210), the adhesive dam portion (231) can perform the role of a dam that prevents the adhesive portion (232) from penetrating into the upper surface of the lower filter (221), thus having the effect of preventing penetration and contamination of the adhesive portion (232) into the lower filter (221).

[0060] As an optional embodiment, the adhesive dam (231) may be formed of a liquid silicone adhesive.

[0061] Referring to FIG. 2 and FIG. 3, the adhesive portion (232) according to one embodiment of the present invention is positioned on the outside of the adhesive dam portion (231) on the base body (210), specifically, it may be positioned in an area on the base body (210) excluding the area where the adhesive dam portion (231) and the lower filter (221) are located.

[0062] The adhesive portion (232) may be formed of the same material as the adhesive dam portion (231), and specifically, may be formed of an insulating material having adhesive performance. As an optional embodiment, the adhesive portion (232) may be a liquid silicone adhesive.

[0063] Referring to FIG. 2 and FIG. 3, a porous filter (220) according to one embodiment of the present invention is disposed between a base body (210) and an adsorption plate (240) and may include a lower filter (221) and an upper filter (222).

[0064] The lower filter (221) and the upper filter (222) can be formed of alumina (Al2O3) material as ceramic filters.

[0065] According to one embodiment of the present invention, the lower filter (221) is in communication with a supply channel (211) formed on the inside of the base body (210), and the upper filter (222) is in communication with a plate hole portion (242) formed on the inside of the adsorption plate (240). Gas (G) supplied from the outside passes through the lower filter (221) via the supply channel (211), and the gas (G) that has passed through the lower filter (221) passes through the upper filter (222) and can be supplied to the wafer (W) through the plate hole portion (242).

[0066] By supplying an inert gas (G), specifically helium gas, to a wafer (W) placed on an adsorption plate (240) through a lower filter (221) and an upper filter (222), a cooling effect can be obtained, and the gas (G) can be prevented from flowing back in the opposite direction (from the upper side to the lower side based on FIG. 2).

[0067] In addition, by not forming a gap between the base body (210) and the lower filter (221) and between the adsorption plate (240) and the upper filter (222), it is possible to prevent arcing from occurring during use of the electrostatic chuck (200) due to such a gap.

[0068] Referring to FIG. 2 and FIG. 3, a porous filter (220) according to one embodiment of the present invention has a lower filter (221) and an upper filter (222) spaced apart from each other and inserted into a base body (210) and an adsorption plate (240), respectively, but is not limited thereto. Various modifications are possible, such as a single shape, where one region is inserted into the base body (210) and another region connected to the one region is inserted into the adsorption plate (240).

[0069] Referring to FIGS. 2 and 3, the adhesive layer (230) is placed between the base body (210) and the adsorption plate (240), and various adhesives capable of bonding dissimilar materials can be used, such as a material having a thermal expansion coefficient similar to that of the adsorption plate (240).

[0070] Referring to FIGS. 2 and 3, the adsorption plate (240) is bonded to the upper surface of the base body (210) by an adhesive layer (230), and can adsorb a wafer (W) by an electrostatic force generated by receiving power from an external source.

[0071] An adsorption plate (240) according to one embodiment of the present invention is positioned at the top of an electrostatic chuck (200), and a wafer (W) can be placed on the upper surface of the adsorption plate (240).

[0072] Referring to FIGS. 2 and FIGS. 3, the adsorption plate (240) may include a plate body (241) and a plate hole portion (242).

[0073] The plate body (241) is on which the wafer (W) is placed, and like the base body (210), it can be manufactured in the shape of a disc. Adsorption electrodes (not shown in the drawing) for chucking or dechucking the wafer (W) based on electrostatic force can be printed on the inside or bottom surface of the plate body (241).

[0074] A plate body (241) according to one embodiment of the present invention may be made of a ceramic material so that it is durable in a high-temperature environment within a chamber and electrostatic force generated from an electrode part (not shown in the drawing) can pass through smoothly.

[0075] For example, the plate body (241) may be made of an Al2O3-based material or a ceramic material such as aluminum nitride (AlN) or silicon carbide (SiC) that has higher thermal conductivity than the Al2O3-based material. However, the material of the adsorption plate (240) is not limited to the examples described above.

[0076] As an optional embodiment, the resistivity of the adsorption plate (240) may be 1013 (Ω·cm) or higher, for the purpose of utilizing the Coulomb force. Accordingly, the electrostatic chuck (200) may be a high-resistance electrostatic chuck (200) utilizing the Coulomb force rather than the Johnsen-Rahbeck (JR).

[0077] Referring to FIGS. 2 and 3, a supply channel (211) may be formed in the base body (210), and an insertion groove (210a) having a predetermined depth may be formed in the shape of a groove on one side (upper side based on FIG. 2) of the base body (210) facing the adsorption plate (240), and a lower filter (221) may be inserted and disposed inside the insertion groove (210a).

[0078] Referring to FIG. 3, when the lower filter (221) is inserted and coupled into the insertion groove (210a), the outer surface of the lower filter (221) can be in close contact with the inner surface of the insertion groove (210a), and a gap, i.e., an empty space, is not formed between the lower surface of the lower filter (221) and the base body (210), thereby preventing an arcing phenomenon that may occur due to the lower filter (221) and the base body (210) being spaced apart.

[0079] Referring to FIGS. 2 and 3, a plate hole portion (242) may be formed in the plate body (241), and a filter groove portion (240a) having a predetermined depth may be formed in the shape of a groove portion on one side (lower side based on FIG. 2) of the plate body (241) facing the base body (210), and an upper filter (222) may be inserted and disposed inside the filter groove portion (240a).

[0080] Referring to FIG. 3, when the upper filter (222) is inserted and coupled into the filter groove (240a), the outer surface of the upper filter (222) is closely coupled with the inner surface of the filter groove (240a), and a gap, i.e., an empty space, is not formed between the upper surface of the upper filter (222) and the adsorption plate (240), specifically the plate body (241), so that an arcing phenomenon that may occur due to the upper filter (222) and the adsorption plate (240) being spaced apart can be prevented.

[0081] Referring to FIG. 2, in an electrostatic chuck (200) according to one embodiment of the present invention, after a wafer (W) is placed on an adsorption plate (240), numerous processes such as sputtering, photolithography, etching, ion implantation, and chemical vapor deposition are performed sequentially or repeatedly, and during such processes, a porous filter (220) may become clogged due to internal polymer contamination, etc.

[0082] Accordingly, the cleaning device (100) for an electrostatic chuck according to one embodiment of the present invention can effectively clean the porous filter (220), thereby effectively preventing the porous filter (220) from becoming clogged and preventing product damage to the adsorption plate (240) during the overhaul process.

[0083] Referring to FIG. 1, a cleaning device (100) for an electrostatic chuck according to one embodiment of the present invention cleans a porous filter (220) contaminated by the use of the electrostatic chuck (200) described above, and may include a solvent supply unit (110), an ultrasonic generating unit (120), and a filter cleaning unit (130-1).

[0084] Referring to FIG. 1 and FIG. 4, a solvent supply unit (110) according to one embodiment of the present invention is for supplying a solvent (S) to the porous filter (220), and can supply the solvent (S) to the porous filter (220) through a plate hole portion (242) formed in the adsorption plate (240) or a supply channel (211) formed in the base body (210).

[0085] As an optional example, the solvent may include at least one of diethyleneglycol-monoethylether, diethyleneglycol-monoethylether acetate, and an acidic substance.

[0086] Referring to FIGS. 1 and FIGS. 4, the solvent supply unit (110) may include a solvent injection jig (111), a solvent injection hose (112), and a suction jig (113).

[0087] In a jig (111) for injecting a solvent according to one embodiment of the present invention, an injection hole portion (111a) communicating with a supply channel (211) of a base body (210) may be formed, and the solvent (S) introduced into the injection hole portion (111a) may be supplied to the supply channel (211).

[0088] A solvent injection hose (112) according to one embodiment of the present invention may be provided on one side of a solvent injection jig (111) and may supply solvent (S) from a solvent storage unit (not shown in the drawing) to an injection hole (111a) of the solvent injection jig (111).

[0089] A suction jig (113) according to one embodiment of the present invention can perform the function of providing suction force in a direction opposite to the direction in which the solvent (S) is supplied, so that the solvent (S) flowing into the injection hole (111a) and the supply channel (211) through the solvent injection hose (112) can easily flow into the porous filter (220).

[0090] To this end, a suction hole portion (113a) communicating with the plate hole portion (242) of the suction plate (240) may be formed inside the suction jig (113), and a vacuum pipe (114) for creating a vacuum into the suction hole portion (113a) may be detachably provided on one side of the suction jig (113) through a connecting member (115).

[0091] Specifically, when a vacuum is generated in the vacuum pipe (114), a vacuum can be generated towards the plate hole portion (242) of the adsorption plate (240) through the suction hole portion (113a) of the suction jig (113), and due to the generated vacuum, the solvent injected into the supply channel (211) is pulled toward the plate hole portion (242) and can flow smoothly into the lower filter (221) and the upper filter (222).

[0092] As an optional embodiment, the vacuum pipe (114) may be connected to an external vacuum source, such as a rotary pump, to create a vacuum inside the suction jig (113), specifically in the suction hole (113a), but is not limited thereto and may be connected to another external vacuum source.

[0093] Meanwhile, although not illustrated in detail, a solvent supply unit (110) according to one embodiment of the present invention may be composed of a simple configuration including a syringe (not shown in the drawing), and may inject a solvent (S) into the plate hole portion (242) of the adsorption plate (240) and the supply channel (211) of the base body (210) using the syringe. For example, the solvent (S) injected into the plate hole portion (241) through the syringe may be supplied to the upper filter (222), and the solvent (S) injected into the supply channel (211) through the syringe may be supplied to the lower filter (221).

[0094] Referring to FIG. 1 and FIG. 5, an ultrasonic generating unit (120) according to one embodiment of the present invention is for generating and supplying ultrasonic waves to a porous filter (220) supplied with a solvent (S). Specifically, ultrasonic vibrations can be transmitted to a porous filter (220) including an upper filter (222) and a lower filter (221) supplied with a solvent through a plate hole portion (242) formed in an adsorption plate (240) facing an upper filter (222).

[0095] At this time, an additional cleaning solvent (125) made of the same material as the solvent of the solvent supply unit (110) may be additionally disposed in the plate hole portion (242) of the adsorption plate (240), and by transmitting ultrasonic waves to the porous filter (220) supplied with the solvent using the additional solvent (125) as a medium, the ultrasonic cleaning process of the porous filter (220) can be performed more effectively.

[0096] Specifically, when a solvent is supplied into a porous filter (220) including an upper filter (222) and a lower filter (221) through a solvent supply unit (110), ultrasonic vibrations can be transmitted to the porous filter (220) together with an additional solvent (125) through an ultrasonic generator (120), and contaminants that are adsorbed to the porous filter (220) and do not easily fall off can be more easily removed through the ultrasonic vibrations transmitted to the porous filter (220) together with the additional solvent (125).

[0097] As an optional embodiment, the ultrasonic generating unit (120) may be an ultrasonic cleaner comprising an ultrasonic vibrator (121) that generates ultrasonic waves by being connected to a high-frequency oscillator (not shown in the drawing). For example, ultrasonic vibrations may be generated using a fine brush that can be inserted into the plate hole portion (242) of the adsorption plate (240) as the ultrasonic vibrator.

[0098] For example, the ultrasonic transducer may include a brush (121) of a fine size of approximately 0.1 to 0.3 mm, specifically 0.2 mm, that can be inserted into the plate hole portion (242), and may be made of a metal material and may generate ultrasonic vibrations for 2 minutes at a frequency of approximately 30 kHz to 50 kHz, specifically 40 kHz, in the plate hole portion (242) and deliver them to the porous filter (220) together with an additional solvent (125).

[0099] Referring to FIGS. 1 and 6, the filter cleaning unit (130-1) and the gas supply unit (130-2) according to one embodiment of the present invention are configured separately to supply cleaning water and fluid gas to the porous filter (220) individually. However, in this embodiment, they are configured as a single unit to supply cleaning water (DI) and fluid gas (G1) to the porous filter (220) simultaneously while the electrostatic chuck (200) is fixed. By supplying fluid gas (G1) together with cleaning water (DI), the cleaning effect of the porous filter (220) can be enhanced.

[0100] Specifically, the filter cleaning unit (130-1) and the gas supply unit (130-2) may include a supply jig (131) and a supply device (132).

[0101] In a supply jig (131) according to one embodiment of the present invention, a supply hole portion (131a) communicating with a supply channel (211) of a base body (210) may be formed.

[0102] Referring to FIG. 6, the supply jig (131) is provided in a vacuum chamber (133) so that the base body (210) of the electrostatic chuck (200) can be seated thereon, and for the secure fixation of the base body (210), the outer edge portion can be joined to the base body (210) through a fastening member (not shown in the drawing).

[0103] In one embodiment of the present invention, when the base body (210) is seated, the supply hole portion (131a) can be connected to the supply channel (211).

[0104] At this time, the supply hole portion (131a) may be provided with a sealing member (not shown in the drawing), such as an O-ring, and the sealing member may be used to maintain airtightness between the supply hole portion (131a) and the supply channel (211).

[0105] A supply device (132) according to one embodiment of the present invention can be connected to a supply jig (131) through a supply line (132a), and can supply cleaning water (DI) and fluid gas (G1) to a supply channel (211) of a base body (210) through the supply line (132a).

[0106] As an optional embodiment, the cleaning water (DI) may include DI water (De-ionized Water) or IPA (Isopropyl Alcohol), and the flowing gas (G1) may include helium (He) gas.

[0107] A supply device (132) according to one embodiment of the present invention can supply cleaning water (DI) to the supply channel (211) of the base body (210) through the supply hole portion (131a) of the supply jig (131) while simultaneously supplying fluid gas (G1).

[0108] Referring to FIG. 6, the cleaning water (DI) and fluid gas (G1) supplied to the supply channel (211) through the supply device (132) can sequentially pass through the porous filter (220), specifically the lower filter (221) and the upper filter (222), to perform the cleaning process of each filter (221, 222), and can be discharged to the outside of the adsorption plate (240) through the plate hole (242) of the adsorption plate (240).

[0109] Referring to FIG. 1 and FIG. 6, a cleaning device (100) for an electrostatic chuck according to one embodiment of the present invention may further include a control unit (150) that controls the operation of a filter cleaning unit (130-1) and a gas supply unit (130-2).

[0110] Specifically, a control unit (150) according to one embodiment of the present invention can control the operation of a supply unit (132) to control the cleaning water (DI) and fluid gas (G1) supplied to a porous filter (220).

[0111] Referring to FIG. 1 and FIG. 6, a cleaning device (100) for an electrostatic chuck according to one embodiment of the present invention may further include a flow sensor unit (140) for detecting the flow amount of a fluid gas (G1) passing through a porous filter (220) in order to determine the time when cleaning of the porous filter (220) is completed.

[0112] Specifically, when contaminants are removed through a cleaning process of the porous filter (220), the fluid gas (G1) can pass through more smoothly, and the flow amount of the fluid gas (G1) passing through the porous filter (220) can be detected in real time by the flow sensor unit (140) to determine the time when the cleaning of the porous filter (220) is completed.

[0113] Referring to FIG. 1 and FIG. 6, a control unit (150) according to one embodiment of the present invention is connected to the flow sensor unit (140) and can receive information regarding the flow amount of the flowing gas (G1) passing through the porous filter (220) detected by the flow sensor unit (140).

[0114] When information regarding the flow rate of the fluid gas (G1) passing through the porous filter (220) is transmitted from the flow sensor unit (140) to the control unit (150), the control unit (150) can determine whether the cleaning of the porous filter (220) is completed by comparing the measured flow rate of the detected fluid gas (G1) with the preset flow rate of the fluid gas (G1).

[0115] Specifically, during the cleaning process in which cleaning water (DI) and fluid gas (G1) are supplied to the porous filter (220) through the supply unit (132), the flow sensor unit (140) can detect and measure the flow amount of fluid gas (G1) passing through the porous filter (220) in real time and transmit it to the control unit (150). The control unit (150) determines that the cleaning of the porous filter (220) is completed when the measured flow amount of fluid gas (G1) measured by the flow sensor unit (140) is greater than or equal to a preset flow amount of fluid gas (G1).

[0116] Referring to FIG. 1 and FIG. 6, when it is determined that the cleaning of the porous filter (220) is completed, the control unit (150) can turn off the operation of the filter cleaning unit (130-1) and the gas supply unit (130-2), i.e., the supply unit (132), to stop the supply of cleaning water (DI) and fluid gas (G1) to the porous filter (220).

[0117] When the measured flow rate of the fluid gas (G1) in the control unit (150) is smaller than the preset flow rate of the fluid gas (G1), the cleaning process of the porous filter (220) can be continued by sequentially and repeatedly driving the solvent supply unit (110), the ultrasonic generator (120), the filter cleaning unit (130-1), and the gas supply unit (130-2) until the measured flow rate of the fluid gas (G1) passing through the porous filter (220) reaches the preset flow rate.

[0118] Meanwhile, referring to FIG. 7, a cleaning device according to another embodiment of the present invention is shown having a base body (210') having a plurality of supply channels (211'), and is shown supplying cleaning water (DI) and gas (G1) to each supply channel (211') through a supplyer (132').

[0119] The cleaning device of the present embodiment may be equipped with a supply jig (131') having a plurality of supply hole portions (131a') corresponding to a plurality of supply channels (211'), and the supply jig (131') may be connected to a cleaning water and gas supply unit (132') that supplies cleaning water (DI) and gas (G1) to the plurality of supply hole portions (131a').

[0120] Hereinafter, a cleaning method for an electrostatic chuck according to one embodiment of the present invention will be described.

[0121] FIG. 8 is a flowchart illustrating a cleaning method for an electrostatic chuck using a cleaning device for an electrostatic chuck according to one embodiment of the present invention.

[0122] Referring to FIG. 1 and FIG. 8, a cleaning method for an electrostatic chuck according to one embodiment of the present invention may include a step of supplying a solvent (S10), a step of generating ultrasound (S20), a step of cleaning a filter (S30), a step of supplying a fluid gas (G1) (S40), and a step of detecting the flow amount of the fluid gas (G1) (S50).

[0123] Referring to FIG. 4 and FIG. 8, the step of supplying a solvent (S10) according to one embodiment of the present invention is to supply a solvent to a porous filter (220) through a solvent supply unit (110).

[0124] A solvent supply unit (110) according to one embodiment of the present invention can supply a solvent to a porous filter (220) through at least one of a plate hole portion (242) formed in an adsorption plate (240) and a supply channel (211) formed in a base body (210).

[0125] As an optional example, the solvent may include at least one of diethyleneglycol-monoethylether, diethyleneglycol-monoethylether acetate, and an acidic substance.

[0126] Referring to FIG. 4, the solvent supply unit (110) may include a solvent injection jig (111), a solvent injection hose (112), and a suction jig (113). An injection hole portion (111a) may be formed in the solvent injection jig (111) that communicates with the supply channel (211) of the base body (210). A solvent injection hose (112) may be provided on one side of the solvent injection jig (111) to inject the solvent into the supply channel (211) through the injection hole portion (111a).

[0127] Referring to FIG. 4, in a suction jig (113) according to one embodiment of the present invention, a suction hole portion (113a) communicating with the plate hole portion (242) of the adsorption plate (240) may be formed.

[0128] A vacuum pipe (114) that generates a vacuum may be provided on one side of the suction jig (113) through a connecting member (115).

[0129] Specifically, when a vacuum is generated in the vacuum pipe (114), a vacuum can be generated towards the plate hole portion (242) of the adsorption plate (240) through the suction hole portion (113a) of the suction jig (113), and due to the generated vacuum, the solvent injected into the supply channel (211) is pulled toward the plate hole portion (242) and can be smoothly supplied to the lower filter (221) and the upper filter (222).

[0130] As an optional embodiment, the vacuum pipe (114) may be connected to an external vacuum source, such as a rotary pump, to create a vacuum inside the suction jig (113), specifically in the suction hole (113a), but is not limited thereto and may be connected to another external vacuum source.

[0131] Referring to FIGS. 5 and FIGS. 8, the step (S20) of generating ultrasound according to one embodiment of the present invention is to supply ultrasonic vibrations to a porous filter (220) through an ultrasonic generating unit (120).

[0132] An ultrasonic generating unit (120) according to one embodiment of the present invention can transmit ultrasonic vibrations to a porous filter (220) through a plate hole portion (242) formed in an adsorption plate (240) facing a porous filter (220), specifically an upper filter (222).

[0133] A cleaning solvent (125) identical to the solvent of the solvent supply unit (110) can be additionally supplied to the plate hole portion (242) of the adsorption plate (240), and by transmitting ultrasound to the porous filter (220) using the additional solvent (125) as a medium, the ultrasonic cleaning process of the porous filter (220) can be performed more effectively.

[0134] Specifically, when a solvent is injected into the porous filter (220) through the aforementioned solvent supply unit (110), ultrasonic vibrations are transmitted to the porous filter (220) along with additional solvent (125) through the ultrasonic supply unit (120), thereby making it easier to remove contaminants that are adsorbed to the porous filter (220) and do not easily fall off.

[0135] As an optional embodiment, the ultrasonic supply unit (120) may be composed of an ultrasonic cleaner including an ultrasonic vibrator (not shown in the drawing) that generates ultrasonic waves and is connected to a high-frequency oscillator (not shown in the drawing).

[0136] For example, in the case of an ultrasonic vibrator, it can be connected to a metal brush (121) of approximately 0.1 to 0.3 mm, specifically 0.2 mm, which can be inserted into the plate hole portion (242) of the adsorption plate (240) as a separate vibrator, and can generate and supply ultrasonic vibrations to the plate hole portion (242) at 30 kHz to 50 kHz, specifically 40 kHz for 2 minutes.

[0137] Referring to FIGS. 6 and FIGS. 8, the step of cleaning a filter (S30) and the step of supplying gas (G1) according to one embodiment of the present invention are steps of cleaning a porous filter (220) by supplying cleaning water (DI) and flowing gas (G1) to a porous filter (220) through a filter cleaning unit (130-1) and a gas supply unit (130-2).

[0138] The cleaning step (S30) and the gas supply step (S40) according to one embodiment of the present invention may be performed sequentially.

[0139] However, it is not limited to this, and the cleaning water (DI) and gas (G1) are supplied simultaneously to the porous filter (220) to clean the porous filter (220), thereby increasing the cleaning effect of the porous filter (220).

[0140] Specifically, the filter cleaning unit (130-1) and the gas supply unit (130-2) may include a supply jig (131) and a supply device (132).

[0141] Referring to FIG. 6, a supply jig (131) according to one embodiment of the present invention may have a supply hole portion (131a) formed therein that communicates with the supply channel (211) of the base body (210).

[0142] The supply jig (131) is provided in a vacuum chamber (133) so that the base body (210) of the electrostatic chuck (200) can be seated thereon, and for the secure fixation of the base body (210), the outer edge portion can be joined to the base body (210) through a fastening member (not shown in the drawing).

[0143] In a supply jig (131) according to one embodiment of the present invention, when a base body (210) is seated, the supply hole portion (131a) may be connected to the supply channel (211). At this time, the supply hole portion (131a) may be provided with a sealing member (not shown in the drawing), such as an O-ring, for example, and the sealing member may maintain airtightness between the supply hole portion (131a) and the supply channel (211).

[0144] Referring to FIG. 6, a supply device (132) according to one embodiment of the present invention can be connected to a supply jig (131) through a supply line (132a), and can supply cleaning water (DI) and fluid gas (G1) to a supply channel (211) of a base body (210) through the supply line (132a).

[0145] As an optional embodiment, the cleaning water (DI) may include DI water (De-ionized Water) or IPA (Isopropyl Alcohol), and the gas (G1) may include helium (He) gas.

[0146] A supply device (132) according to one embodiment of the present invention can supply cleaning water (DI) to the supply channel (211) of the base body (210) and simultaneously supply fluid gas (G1), and the cleaning water (DI) and fluid gas (G1) supplied to the supply channel (211) can sequentially pass through the porous filter (220), specifically the lower filter (221) and the upper filter (222), perform a cleaning process of the porous filter (220), and then be discharged into the vacuum chamber through the plate hole (242) of the adsorption plate (240).

[0147] Referring to FIGS. 1, 6, and 8, a control unit (150) according to one embodiment of the present invention can detect the flow amount of fluid gas (G1) passing through the porous filter (220) during the cleaning process of the porous filter (220) to determine the time when the cleaning of the porous filter (220) is completed.

[0148] Specifically, during the process of cleaning the porous filter (220) by supplying cleaning water (DI) and fluid gas (G1) to the porous filter (220) through the supply unit (132), the control unit (150) can determine whether the cleaning of the porous filter (220) is completed by comparing the measured flow rate of the fluid gas (G1) with a preset flow rate.

[0149] For example, during a cleaning process in which cleaning water (DI) and fluid gas (G1) are supplied to a porous filter (220) through a supply unit (132), the flow sensor unit (140) can detect and measure the flow amount of fluid gas (G1) passing through the porous filter (220) in real time and transmit it to the control unit (150). The control unit (150) determines that the cleaning of the porous filter (220) is completed if the measured flow amount of fluid gas (G1) transmitted from the flow sensor unit (140) is greater than or equal to a preset flow amount of fluid gas (G1).

[0150] Referring to FIGS. 6 and FIGS. 8, when it is determined that cleaning of the porous filter (220) according to one embodiment of the present invention is completed, the control unit (150) can turn off the operation of the filter cleaning unit (130-1) and the gas supply unit (130-2), i.e., the supply unit (132), to terminate the supply of cleaning water (DI) and fluid gas (G1) to the porous filter (220).

[0151] In the control unit (150) according to one embodiment of the present invention, if the measured flow rate of the fluid gas (G1) is smaller than the preset flow rate of the fluid gas (G1), the cleaning process of the porous filter (220) can be continued by sequentially and repeatedly driving the solvent supply unit (110), the ultrasonic generator (120), the filter cleaning unit (130-1), and the gas supply unit (130-2) until the measured flow rate of the fluid gas (G1) passing through the porous filter (220) reaches the preset flow rate.

[0152] Although preferred embodiments of the present invention have been illustrated and described above, the present invention is not limited to the specific embodiments described above. Various modifications are possible by those skilled in the art without departing from the essence of the invention as claimed in the claims, and such modifications should not be understood individually from the technical spirit or perspective of the present invention. Explanation of the symbols

[0153] 100: Cleaning device for electrostatic chuck DI: Cleaning water G: Gas G1: Fluid gas S: Solvent W: Wafer 110: Solvent supply unit 120: Ultrasonic generator 130-1: Filter cleaning unit 130-2: Gas supply unit 140: Flow sensor unit 150: Control unit 200: Electrostatic Chuck 210: Base Body 220: Porous filter 221: Bottom filter 222: Upper filter 230: Adhesive layer 240: Adsorption plate

Claims

Claim 1 A method for cleaning an electrostatic chuck, comprising: a step of supplying a solvent to a porous filter of an electrostatic chuck; a step of generating ultrasound to the porous filter to which the solvent has been supplied; and a step of supplying cleaning water to the porous filter and cleaning the porous filter; wherein the step of cleaning the porous filter comprises: a step of supplying the cleaning water to the porous filter; and a step of supplying a fluid gas to the porous filter. Claim 2 A cleaning method for an electrostatic chuck according to claim 1, wherein the electrostatic chuck comprises: a base body; an adsorption plate disposed facing the base body; and a porous filter disposed between the base body and the adsorption plate; and wherein the step of supplying the solvent is characterized by supplying the solvent to the porous filter through a plate hole portion formed in the adsorption plate and a supply channel formed in the base body. Claim 3 A cleaning method for an electrostatic chuck according to paragraph 2, wherein the step of generating the ultrasonic waves is characterized by transmitting ultrasonic vibrations to the porous filter through the solvent located in the plate hole portion. Claim 4 delete Claim 5 A cleaning method for an electrostatic chuck according to claim 1, wherein the solvent comprises at least one of diethyleneglycol-monoethylether, diethyleneglycol-monoethylether acetate, and an acidic substance. Claim 6 A cleaning device for an electrostatic chuck, characterized by comprising: a solvent supply unit for supplying a solvent to a porous filter provided in an electrostatic chuck; an ultrasonic generator for generating ultrasonic waves to the porous filter to which the solvent is supplied; and a filter cleaning unit for supplying cleaning water to one side of the porous filter, discharging cleaning water from the other side of the porous filter, and cleaning the porous filter. Claim 7 A cleaning device for an electrostatic chuck according to claim 6, further comprising: a gas supply unit for supplying fluid gas to the porous filter; and a flow sensor unit for detecting the amount of fluid gas supplied from the gas supply unit and passing through the porous filter.

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