Large-area bonding type substrate fixing device and manufacturing method therefor

Abstract

An embodiment of the present invention relates to a large-area bonding type substrate fixing device. The technical problem to be solved is to provide a large-area bonding type substrate fixing device which implements a large-area electrostatic chuck and has excellent flatness by bonding and fixing a plurality of electrostatic chucks onto one base member in the horizontal direction. To this end, disclosed is a substrate fixing device comprising: a base member; a plurality of electrostatic chucks provided on the base member and fixing a substrate by electrostatic force; and a plurality of bonding layers bonding the base member and the plurality of electrostatic chucks to each other, wherein the plurality of electrostatic chucks are provided with grooves along the peripheries thereof, a bonding layer is filled in the grooves to bond the plurality of electrostatic chucks to each other, each of the plurality of electrostatic chucks comprises a ceramic plate and an electrode layer provided on the ceramic plate, and the bonding layers bond the ceramic plate and the electrode layer onto the base member.

Description

Large-area bonded substrate fixing device and method of manufacturing the same

[0001] An embodiment of the present invention relates to a large-area bonded substrate fixing device and a method for manufacturing the same.

[0002] Recent technological trends in manufacturing processes for semiconductors and display panels, such as the enlargement of wafers, glass substrates, or film substrates, high circuit integration, ultra-fine processing, and plasma etching processes, are demanding a major revolution in the methods of fixing wafers, glass substrates, or film substrates used in thin film deposition and etching processes.

[0003] Conventionally, wafers, glass substrates, or film substrates as described above have been fixed using mechanical clamps or vacuum chucks; however, in recent next-generation semiconductor and display panel process equipment, electrostatic chucks utilizing electrostatic force are used as core components to fix the wafers, glass substrates, or film substrates.

[0004] The electrostatic chuck is a device that fixes a wafer, glass substrate, or film substrate by means of an electrostatic force generated between the wafer, glass substrate, or film substrate and the dielectric, by applying a DC voltage to a conductive electrode, thereby causing opposite polarity to be generated on the wafer, glass substrate, or film substrate according to the polarization phenomenon of the dielectric, and by means of an electrostatic force generated between the wafer, glass substrate, or film substrate and the dielectric when an opposite polarity is generated on the wafer, glass substrate, or film substrate that is the workpiece, according to the polarization phenomenon of the dielectric.

[0005] At this time, the electrostatic chuck described above is gradually becoming larger due to the increasing size of wafers, glass substrates, or film substrates, and as the electrostatic chuck becomes larger, the base material equipped in the electrostatic chuck is also becoming increasingly larger.

[0006] Meanwhile, the base material of the electrostatic chuck described above has been manufactured and used using ceramic, which does not undergo deformation even at high temperatures, because the temperature rises above 80°C when the electrostatic chuck is used.

[0007] At that time, due to limitations in technology and equipment, it was not possible to manufacture the base material formed from ceramic as described above with a width and length of 1000 to 1200 mm or more both domestically and internationally.

[0008] In addition, the above-mentioned base material is not only expensive, but when manufacturing a large base material as a single object to match the increase in size of the electrostatic chuck, there were problems such as the high cost of the base material and the need for a lot of time and cost to process the flatness of the outer surface of the base material to an ultra-precision flatness of 30 μm or less, and the problem of the defect rate of the base material also increased.

[0009] The information described above disclosed in the background technology of this invention is intended only to enhance understanding of the background of the present invention and may therefore include information that does not constitute prior art.

[0010] The objective of the present invention is to provide a substrate fixing device that implements a large-area electrostatic chuck by horizontally bonding a plurality of electrostatic chucks onto a single base member. This enables stable fixing of various workpieces, such as large wafers, glass substrates, and film substrates, and ensures high flatness and uniform electrostatic chucking force required in semiconductor and display manufacturing processes.

[0011] In addition, the present invention aims to improve the mechanical strength and durability of a large-scale substrate fixing device by firmly bonding the electrostatic chuck through a bonding layer, and to improve productivity by facilitating the fabrication and assembly of individual electrostatic chuck modules.

[0012] Additionally, the present invention aims to ensure long-term reliability and ease of maintenance in semiconductor and display manufacturing processes by providing a substrate fixing device having high heat resistance, vacuum resistance, and chemical resistance through optimized material design of the bonding layer and the bonding layer.

[0013] A large-area bonding type substrate fixing device according to an embodiment of the present invention comprises: a base member; a plurality of electrostatic chucks provided on the base member to fix a substrate by electrostatic force; and a plurality of bonding layers that bond the base member and the plurality of electrostatic chucks to each other, wherein the plurality of electrostatic chucks are provided with grooves along their circumference and the bonding layer is filled into the grooves to bond the plurality of electrostatic chucks to each other, and each of the plurality of electrostatic chucks includes a ceramic plate and an electrode layer provided on the ceramic plate, and the bonding layer bonds the ceramic plate and the electrode layer to the base member.

[0014] In one or more embodiments, each of the electrostatic chucks further comprises a coating layer covering the ceramic plate and the electrode layer, and the bonding layer bonds the coating layer onto the base member.

[0015] In one or more embodiments, the coating layer is formed on the ceramic plate and the electrode layer by means of atmospheric plasma spray, aerosol deposition, high velocity oxygen fuel (HVOF), cold spray, or flame spray.

[0016] In one or more embodiments, the bonding layer is provided over the entire upper surface of the ceramic plate outside the groove and the groove.

[0017] In one or more embodiments, a plurality of support members are further provided penetrating the bonding layer between the upper side of the base member and the lower side of the ceramic plate.

[0018] In one or more embodiments, the plurality of support members extend from the base member toward the ceramic plate or extend from the ceramic plate toward the base member.

[0019] In one or more embodiments, the outermost support member among the plurality of support members joins the base member and the outermost part of the ceramic plate to each other so that the bonding layer is not exposed to the outside.

[0020] In one or more embodiments, the bonding layer is provided by filling between the base member and the ceramic plate, which are spaced apart from each other by the plurality of support members.

[0021] A large-area bonding type substrate fixing device according to an embodiment of the present invention comprises: a base member; a plurality of lower bonding layers provided on the base member; a plurality of polyimide electrostatic chucks each provided on the plurality of lower bonding layers to fix a substrate by electrostatic force; a plurality of upper bonding layers each provided on the plurality of polyimide electrostatic chucks; and a plurality of ceramic plates each provided on the plurality of upper bonding layers to mount the substrate, wherein the plurality of ceramic plates are provided with grooves along their periphery, and a bonding layer is filled into the grooves to bond the plurality of ceramic plates to each other.

[0022] In one or more embodiments, the bonding layer is provided over the entire upper surface of the ceramic plate outside the groove and the groove.

[0023] In one or more embodiments, the base member comprises ceramic, aluminum, titanium, MMC (Metal Matrix Composite), or SUS (Steel Use Stainless).

[0024] In one or more embodiments, the polyimide electrostatic chuck comprises a polyimide insulating layer and an electrode layer provided on the polyimide insulating layer.

[0025] In one or more embodiments, the polyimide insulating layer has a thermal decomposition temperature of 450 °C to 600 °C, a continuous use temperature of 250 °C to 400 °C, a dielectric constant of 3.0 to 3.6 (based on 1 kHz), a dielectric breakdown strength of 200 kV / mm to 300 kV / mm, a coefficient of thermal expansion of 4 ppm / °C to 80 ppm / °C, a hygroscopicity of 0.1% to 1%, and a tensile strength of 100 MPa to 200 MPa.

[0026] In one or more embodiments, the thickness of the polyimide insulating layer is 10 μm to 500 μm.

[0027] A large-area bonded substrate fixing device according to an embodiment of the present invention comprises: a base member; a plurality of polyimide electrostatic chucks bonded to the base member to fix a substrate by electrostatic force; and a plurality of ceramic plates each bonded to the plurality of polyimide electrostatic chucks on which the substrate is mounted, wherein the plurality of ceramic plates are provided with grooves along their periphery, and a bonding layer is filled into the grooves to bond the plurality of ceramic plates to each other.

[0028] In one or more embodiments, the polyimide electrostatic chuck comprises a first polyimide insulating layer, an electrode layer provided on the first polyimide insulating layer, and a second polyimide insulating layer covering the first polyimide insulating layer and the electrode layer.

[0029] In one or more embodiments, the base member, the polyimide electrostatic chuck, and the ceramic plate are joined to each other by heat pressurization after the surface is activated through plasma treatment and the polyimide electrostatic chuck is interposed between the base member and the ceramic plate.

[0030] In one or more embodiments, after a primer comprising a silane coupling agent, a titanium or aluminum-based compound is coated on the surface of the polyimide electrostatic chuck, the polyimide electrostatic chuck is interposed between the base member and the ceramic plate and then heat-pressed to bond them together.

[0031] In one or more embodiments, the base member, the polyimide electrostatic chuck, and the ceramic plate are joined to each other by heat pressing after a sandblasting layer is formed on their surfaces, and the polyimide electrostatic chuck is interposed between the base member and the ceramic plate.

[0032] In one or more embodiments of a ceramic plate, the base member, the polyimide electrostatic chuck, and the ceramic plate are heat-pressed to be joined to each other under conditions where a temperature higher than the glass transition temperature of the polyimide electrostatic chuck is provided.

[0033] The present invention overcomes the manufacturing limitations of conventional single large ceramic electrostatic chucks by implementing a large-area electrostatic chuck, and provides the effect of uniformly fixing large substrates while maintaining high flatness. This enables the maintenance of uniform process quality in semiconductor and display processes and prevents minute deformation of the substrate, thereby allowing for high-precision processes.

[0034] Furthermore, the bonding layer and bonding layer of the present invention ensure a robust connection between electrostatic chucks while improving the durability of the joint, thereby maintaining uniform chucking force and heat resistance even in long-term usage environments. In particular, it can exhibit stable performance even in plasma processes and corrosive gas environments, providing high reliability in semiconductor and display manufacturing processes.

[0035] Furthermore, by applying a multi-layered structure and a modular design, the present invention ensures flexibility in the manufacturing process and enables partial replacement of damaged individual electrostatic chucks, thereby providing the effect of reducing maintenance costs. As a result, cost efficiency and productivity can be maximized in various industrial processes that utilize large electrostatic chucks.

[0036] FIG. 1 is a plan view illustrating a large-area bonded substrate fixing device according to an embodiment of the present invention.

[0037] FIG. 2 is a cross-sectional view illustrating a large-area bonded substrate fixing device according to an embodiment of the present invention.

[0038] FIG. 3 is a flowchart illustrating a method for manufacturing a large-area bonded substrate fixing device according to an embodiment of the present invention.

[0039] FIGS. 4a to 4d are cross-sectional views illustrating a method for manufacturing a large-area bonded substrate fixing device according to an embodiment of the present invention.

[0040] FIGS. 5 to 15 are cross-sectional views illustrating a large-area bonded substrate fixing device according to another embodiment of the present invention.

[0041] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the attached drawings.

[0042] The embodiments of the present invention are provided to more fully explain the invention to those skilled in the art, and the following embodiments may be modified in various different forms, and the scope of the invention is not limited to the following embodiments. Rather, these embodiments are provided to make the disclosure more faithful and complete and to fully convey the spirit of the invention to those skilled in the art.

[0043] Additionally, in the drawings below, the thickness or size of each layer is exaggerated for convenience and clarity of explanation, and like reference numerals in the drawings refer to like elements. As used herein, the term "and / or" includes any one of the listed items and all combinations of one or more thereof. Furthermore, in this specification, the meaning of "connected" refers not only to cases where Member A and Member B are directly connected, but also to cases where Member C is interposed between Member A and Member B so that Member A and Member B are indirectly connected.

[0044] The terms used herein are for describing specific embodiments and are not intended to limit the invention. As used herein, the singular form may include the plural form unless the context clearly indicates otherwise. Additionally, as used herein, "comprise, include" and / or "comprising, including" specify the presence of the mentioned features, numbers, steps, actions, parts, elements, and / or groups thereof, and do not exclude the presence or addition of one or more other features, numbers, actions, parts, elements, and / or groups.

[0045] Although terms such as "first," "second," etc. are used in this specification to describe various components, parts, regions, layers, and / or parts, it is obvious that these components, parts, regions, layers, and / or parts should not be limited by these terms. These terms are used solely to distinguish one component, part, region, layer, or part from another region, layer, or part. Accordingly, the first component, part, region, layer, or part described below may refer to the second component, part, region, layer, or part without departing from the teachings of the present invention.

[0046] Spatial terms such as "beneath," "below," "lower," "above," and "upper" may be used to facilitate understanding of one element or feature depicted in the drawings and another element or feature. These spatial terms are intended to facilitate understanding of the invention according to various process or usage conditions of the invention and are not intended to limit the invention. For example, if an element or feature in the drawings is inverted, an element or feature described as "beneath" or "below" becomes "upper" or "upper." Therefore, "beneath" is a concept that encompasses "upper" or "below."

[0047] FIG. 1 is a plan view illustrating a large-area bonded substrate fixing device (100) according to an embodiment of the present invention, and FIG. 2 is a cross-sectional view illustrating a large-area bonded substrate fixing device (100) according to an embodiment of the present invention.

[0048] As illustrated in FIGS. 1 and 2, a large-area bonded substrate fixing device (100) according to an embodiment of the present invention may include a base member (110), a plurality of electrostatic chucks (120), a plurality of bonding layers (130), and a plurality of bonding layers (140).

[0049] In one or more embodiments, for example, 10 electrostatic chucks (120) may be arranged in a matrix form with rows and columns on a base member (110), and the 10 electrostatic chucks (120) may also be joined to each other through a bonding layer (140).

[0050] In one or more embodiments, one electrostatic chuck (120) may have a length of 500 mm in width and 700 mm in height. Accordingly, the bonded substrate fixing device (100) according to an embodiment of the present invention may have a length of 2500 mm in width and 1400 mm in height, thereby being able to sufficiently fix a glass substrate for an 8th or 16th generation display.

[0051] The base member (110) may include a lower region (112) with a relatively large width and an upper region (114) with a relatively small width on the lower region (112). In one or more embodiments, a plurality of cooling lines (111) may be provided in the lower region (112) with a predetermined pitch, and heating lines (113) may be provided in the upper region (114) with a predetermined pitch. Of course, the opposite is also possible. A cooling medium may flow through the cooling lines (111) to cool the lower region (112) of the base member (110) to a predetermined temperature, and current may flow through the heating lines (113) to heat the upper region (114) of the base member (110) to a predetermined temperature. In one or more embodiments, the heating lines (113) may be made of a nickel-chromium heating wire and an insulator that surrounds it.

[0052] In one or more embodiments, the base member (110) may be provided in pure titanium or a titanium alloy. For pure titanium and / or titanium alloys, the thermal expansion coefficient (in units of m / m °C is approximately 7 x 10⁻⁶) -6 Up to approximately 11 x 10 -6It can be, and in the case of aluminum, the coefficient of thermal expansion is 23 x 10 -6 It may be. In one or more embodiments, the base member (110) may include, in addition to titanium, ceramic, aluminum, Inconel, MMC (Metal Matrix Composite), SUS (Steel Use Stainless), or an alloy thereof.

[0053] An electrostatic chuck (120) is provided on a base member (110) to secure a substrate by electrostatic force. In one or more embodiments, when used for a display, one electrostatic chuck (120) may have a length of 500 mm in width and 700 mm in height. In one or more embodiments, when used for a semiconductor, one electrostatic chuck (120) may have a diameter of approximately 50 mm to approximately 300 mm. That is, the electrostatic chuck may be used alone instead of being arranged in a matrix form.

[0054] The electrostatic chuck (120) may include a ceramic plate (121) and an electrode layer (122) provided on the ceramic plate (121) (e.g., on the lower surface).

[0055] The ceramic plate (121) may comprise a ceramic sintered body, glass, or quartz. In one or more embodiments, the ceramic plate or ceramic sintered body (121) may be formed into a roughly plate shape by a molded body made of ceramic powder at a preset temperature, time, and pressure. In one or more embodiments, the ceramic plate (121) may comprise zirconia (ZrO2), beryllium oxide (BeO), aluminum oxide (Al2O3), aluminum nitride (AlN), silicon carbide (SiC), silicon nitride (Si3N4), aluminum titanate (Al2TiO5), yttrium oxide (Y2O3) and / or yttrium oxide (YOF).

[0056] In one or more embodiments, the ceramic plate (121) may be completed through a weighing step, a mixing step, a drying step, a crushing step, a calcining step, a forming step, and a sintering step, which are described in more detail as follows.

[0057] In the weighing step, since the type and amount of additive components of the basic composition vary depending on the composition of the material, the molar amount of the constituent element and the amount of additive are converted into a weight ratio and weighed. In this step, purity compensation of the constituent element is performed to obtain ceramics of accurate purity.

[0058] In the mixing step, a wet mixing method may be used. The wet method provides good mixing and grinding effects. The uniformity of the mixture is important and affects the reaction properties during the calcining step. A ball mill may be used as the mixer. An appropriate amount of alcohol is added to the ball mill container along with the raw materials. Additionally, balls are used to enhance the mixing effect; for example, in the case of piezoelectric materials, since the mixing of iron is extremely poor, porcelain balls are preferred. A weight ratio of 1:1:1 for raw materials, alcohol, and balls is appropriate, but this ratio varies depending on the properties and shape of the starting materials. To uniformly disperse the raw materials, the mill rotation time must be several hours to tens of hours. In this invention, mixing was performed for 20 hours. Balls that minimize wear on the sample during mixing are preferred. In this invention, stabilized ZrO2 balls were used.

[0059] In the drying step, since the mixture after dehydration contains a large amount of moisture, it is dried by maintaining it at approximately 100°C to approximately 120°C for approximately 10 hours or more.

[0060] In the grinding step, since the raw materials reacted in the solid phase often have partially large particles and contain unreacted substances, the particles must be fined to improve reactivity; however, since it is difficult to obtain fine powder in the case of hard particles, fine particles are produced using, for example, an 80-mesh sieve.

[0061] In the calcination stage, the mixture is preheated into a powder or combined form. Without calcination, the volume shrinkage of the sintered sample is large, making it prone to cracking and difficult to obtain the required sintered ceramic. For this reason, the calcination process is necessary. However, if the temperature is too high, it becomes difficult to grind in the subsequent process, so the heat treatment is performed at a temperature approximately 200°C lower than the sintering temperature. Since the calcination temperature is determined by the basic composition, added impurities, and starting materials, the temperature for the calcination stage is generally determined by comparing the results of thermal mass spectrometry (TGA) and differential thermal analysis (DTA) on the powders that have undergone the clearing and mixing stages, and confirming the curve of the fine reaction.

[0062] In the molding step, the ceramic plate (121) is shaped according to the required thickness, width, and shape. In one or more embodiments, the molding step causes the ceramic plate (121) to have a plate shape that is approximately rectangular, square, or circular. Possible molding methods include powder compression, injection, roll rolling, and doctor blade methods. Powder compression is the most common molding method and is widely used. A binder is added to maintain mechanical strength and facilitate handling when molding ceramics; the binder must have properties such as strong bonding strength, easy dispersion at low temperatures, and the ability of the particles after assembly to be easily deformed by molding pressure. The binder used in the present invention (4 wt%, PVA: commonly referred to as "Binder") is mixed at a ratio of approximately 4 cc per approximately 100 g. To improve the dispersion of the PVA solution, a pressure of approximately 300 kg / cm² is applied.3 Pressure is applied and passed through a stainless steel mesh with a diameter of approximately 0.2 mm to form granules. This granulated powder is placed into a molding die equipped with a predetermined shape and subjected to approximately 1000 kg / cm² 2 It is formed by applying pressure.

[0063] Finally, in the sintering step, the molded sample is placed on a substrate such as Al2O3, MgO, or ZrO2, which does not react with the compositional material, and is maintained at approximately 500°C for approximately 4 hours to volatilize the PVA, then sintered at an optimal temperature for approximately 2 hours, and the temperature rise and fall time is approximately 2°C / min to obtain a high-quality ceramic plate (121) that is not subjected to stress such as warping.

[0064] In one or more embodiments, in addition to particle size control and sintering condition optimization, the flatness of the ceramic plate (121) can be improved through an additional surface treatment process after sintering. For example, the surface of the ceramic plate (121) can be ground or polished.

[0065] An electrostatic chuck is a device that fixes or attaches objects by utilizing electromagnetic properties, and is particularly useful for fixing objects using electrical attraction. Electrostatic chucks equipped with high-resistance ceramic plates, high-dielectric constant ceramic plates, or low-resistance ceramic plates help to achieve superior performance by optimizing their electrical characteristics. Here, high resistance, high dielectric constant, or low resistance characteristics can be provided to the ceramic sintered body.

[0066] In one or more embodiments, the high-resistance ceramic is a material with excellent electrical insulation properties that serves to block the flow of current. The primary purpose of using the high-resistance ceramic in the electrostatic chuck is to minimize electrical interference and improve the insulation of the electrostatic chuck.

[0067] For example, high-resistance ceramics provide excellent insulation performance by controlling the microstructure within the ceramic layer. For instance, ceramics mixed with Al2O3, Y2O3, and SiO2 reduce porosity to enhance electrical insulation, thereby helping the electrostatic chuck operate stably without electrical interference.

[0068] In addition, another important feature of high-resistance ceramics is that they exhibit excellent resistance even in plasma environments. Y3Al5O in ceramic 12 By including a microcrystalline phase such as that, it reacts with a fluorine-based plasma to form compounds such as AlF3 and YF3. These compounds provide high etching resistance, allowing the electrostatic chuck to be used for a long time even in a plasma environment.

[0069] As another example, high-dielectric ceramics possess high relative permittivity, making them highly capable of storing and converting electrical energy. Using high-dielectric ceramics in electrostatic chucks enables stronger electrical adsorption.

[0070] For example, high-dielectric-constant ceramic plates control the dielectric properties of the ceramic, allowing the electrostatic chuck to exert a stronger adsorption force even at the same voltage. Using materials with a high relative dielectric constant increases the chucking force of the electrostatic chuck and strengthens the electrical adsorption force.

[0071] As another example, to increase the high dielectric constant, a ceramic plate is formed by mixing materials with high relative dielectric constants, such as BaTiO₃, SrTiO₃, and YSZ, into an Al₂O₃ matrix. In this way, dielectric properties can be improved while maintaining volume resistivity, allowing the electrostatic chuck to operate more efficiently.

[0072] In one or more embodiments, the low-resistance ceramic plate has high electrical conductivity, which allows current to flow easily. When applied to an electrostatic chuck, the electrical properties of this material can be utilized to provide efficient electrical connection and antistatic functions.

[0073] For example, low-resistance ceramics allow current to flow smoothly, effectively providing an antistatic function in electrostatic chucks. For instance, ceramic powder can be applied using a mixed composition of Al2O3 and Y2O3 as a matrix and TiO2 as a filler. This forms a low-resistance dielectric layer, thereby enhancing the antistatic performance of the electrostatic chuck.

[0074] As another example, low-resistance ceramics have a volume resistivity of 10 9 10 at Ω·cm 13 It is adjusted to between Ω·cm to stably maintain the electrical characteristics of the electrostatic chuck and to ensure it is not sensitive to electrical shocks or changes. In addition, this dielectric layer can be combined with the electrostatic chuck electrode to contribute to improving electrical adsorption force and de-chucking speed.

[0075] As another example, electrostatic chucks using low-resistance ceramics have faster de-chucking speeds and exhibit higher chucking force compared to high-resistance electrostatic chucks. For instance, compared to high-resistance chucks, low-resistance chucks de-chucking faster and exhibit stronger chucking force at the same voltage.

[0076] In summary, high-resistance ceramics, high-dielectric constant ceramics, and low-resistance ceramics each provide important electrical characteristics in electrostatic chucks and can optimize performance in different ways.

[0077] In other words, high-resistance ceramics enhance electrical insulation and block current flow. This minimizes electrical interference in the electrostatic chuck and provides high durability even in plasma environments. High-resistance ceramics improve plasma characteristics, enabling long-term use.

[0078] In addition, high-dielectric-constant ceramics increase the relative dielectric constant, helping the electrostatic chuck to exert stronger adsorption force at the same voltage. By optimizing the dielectric properties of the electrostatic chuck, these ceramics increase electrical adsorption and chucking forces, and can improve dielectric properties while maintaining electrical characteristics.

[0079] Finally, low-resistance ceramics enable the smooth flow of current, thereby enhancing the antistatic performance of the electrostatic chuck. They offer excellent electrical properties, accelerate the de-chucking speed of the electrostatic chuck, and provide higher chucking force. These ceramics contribute to optimizing the electrical connectivity and antistatic performance of the electrostatic chuck.

[0080] These high-resistance ceramics, high-dielectric ceramics, or low-resistance ceramics can be applied to the bonding layer described below in the same or similar ways.

[0081] In addition, when using glass and quartz instead of ceramic in an electrostatic chuck, it is important to select the appropriate type because each material offers different physical and electrical properties compared to ceramic. Glass and quartz can be selected based on properties such as stability in high-temperature environments, electrical insulation, and mechanical strength, respectively.

[0082] In one or more embodiments, the glass is characterized by providing electrical insulation while maintaining stable properties in high-temperature environments. When using glass in an electrostatic chuck, for example, borosilicate glass and aluminosilicate glass may be included. Borosilicate glass provides high heat resistance and excellent mechanical strength, maintaining stable properties even in high-temperature environments. Another option, aluminosilicate glass, provides higher heat resistance and chemical resistance than borosilicate and maintains stable properties even in high-temperature and high-pressure environments. Therefore, it is very useful as a dielectric and insulating layer in an electrostatic chuck.

[0083] Quartz is a material that provides excellent electrical insulation and heat resistance, allowing it to be used stably even in high-temperature environments. Quartz may include sodium quartz and Peek quartz. Sodium quartz offers higher electrical insulation than general silicon quartz and ensures stable properties even in high-temperature environments. Additionally, due to its excellent chemical stability, it can be utilized as a dielectric layer in electrostatic chucks. Peek quartz is a high-quality quartz material with excellent heat resistance and electrical insulation. It exhibits stable performance even in high-temperature environments exceeding 1000°C and can play an important role in electrostatic chucks. Therefore, Peek quartz is suitable as a dielectric or insulating layer in electrostatic chucks in high-temperature environments.

[0084] In conclusion, glass and quartz used as substitutes for ceramic in electrostatic chucks in high-temperature environments can be selected according to their respective characteristics. Borosilicate glass and aluminosilicate glass are suitable for the dielectric and insulating layers of electrostatic chucks where heat resistance and electrical insulation are important, while sodium quartz and Peek quartz can be used stably in high-temperature environments due to their excellent heat resistance and electrical insulation properties.

[0085] The electrode layer (122) is intended to fix the substrate. For example, two electrodes (bipolar type) or one electrode (monopolar type) may be provided directly on the ceramic plate (121). In one or more embodiments, the electrode layer (122) may include a conductive material such as aluminum, copper, molybdenum, silver, tungsten, titanium, or a conductive oxide.

[0086] Methods for directly forming an electrode layer (122), such as aluminum, copper, molybdenum, silver, tungsten, titanium, or a conductive oxide, on a ceramic plate (121) include thin film deposition, thick electrode layer formation, electroplating and chemical plating, dispensing, and laser-based deposition. Each method may be selected considering the physical and chemical properties of the ceramic plate (121) and the requirements of the manufacturing process.

[0087] First, thin film deposition methods are divided into physical vapor deposition (PVD) and chemical vapor deposition (CVD) methods. Physical vapor deposition methods include sputtering and electron beam deposition. The sputtering process involves depositing electrode material by ion collision using an inert gas, providing uniform thickness and excellent adhesion. In the case of electron beam deposition, metal is evaporated and deposited using a high-energy electron beam, enabling high-speed deposition and easy application in low-temperature processes. The chemical vapor deposition method involves thermally decomposing a metal-organic compound to form an electrode layer on the surface of a ceramic plate (121), which has the advantage of forming a thin film with a dense structure.

[0088] Methods for forming a thick electrode layer include screen printing, inkjet printing, and plasma spraying. The screen printing process forms an electrode layer by printing a metal paste in a desired pattern and then performing heat treatment; it is suitable for large-area processes and has the advantage of being economical. The inkjet printing process forms an electrode layer by precisely printing ink containing nano-sized metal particles onto the surface of a ceramic plate (121) and then performing heat treatment; this method provides high resolution and can realize patterns of complex shapes. Plasma spraying forms a thick electrode layer by directly spraying metal powder onto a ceramic plate (121) using high-temperature plasma, providing high durability and mechanical strength.

[0089] Electroplating and chemical plating methods can be used to form a uniform electrode layer on a ceramic plate (121). In the case of electroplating, a metal layer is deposited by applying current through a seed layer formed in advance on the ceramic surface, and it is possible to form a metal layer with high conductivity and a thick layer. On the other hand, chemical plating (or electroplating) forms an electrode layer without current using a catalytic reaction and has the advantage of being applicable to non-conductive substrates.

[0090] Finally, the laser-based deposition method involves evaporating a metal target using a laser ablation technique and depositing it onto the surface of a ceramic plate (121), which can provide precise pattern formation and high adhesion. By comprehensively considering these methods, the optimal method can be selected after comprehensively reviewing the physical properties, adhesion, thermal stability, and manufacturing costs of the electrode.

[0091] The bonding layer (130) serves to bond the ceramic plate (121) and the electrode layer (122) onto the base member (110). In one or more embodiments, the bonding layer (130) may be provided directly onto the ceramic plate (121) and the electrode layer (122). In one or more embodiments, the bonding layer (130) may also be provided directly onto the base member (110).

[0092] The bonding layer (130) may include an epoxy-based, silicone-based, or polyimide-based bonding material having heat resistance of approximately 200°C to approximately 400°C.

[0093] The epoxy adhesive provides excellent adhesion and heat resistance, and is particularly excellent in adhesion to a metal base member (110) and a ceramic plate (121). In one or more embodiments, the epoxy adhesive is "3M TM Scotch-Weld TM It may include Epoxy Adhesive 2216", "Loctite EA 9394", and "Master Bond EP42HT-2".

[0094] "3M TM Scotch-Weld TMEpoxy Adhesive 2216" has a heat resistance of approximately -55°C to approximately 177°C, excellent insulation properties, and excellent shock and vibration resistance, making it suitable for bonding semiconductor equipment and high-temperature environments. "Loctite EA 9394" has a continuous operating temperature of approximately 230°C and withstands instantaneous temperatures of approximately 300°C or higher. It has excellent chemical and moisture resistance and high electrical insulation performance (e.g., insulation strength: >15 kV / mm), making it suitable for vacuum environments. "Master Bond EP42HT-2" has a heat resistance of approximately up to 260°C, possesses excellent chemical resistance and electrical insulation properties, and has a low coefficient of thermal expansion, making it suitable for bonding with metals and ceramics. In particular, it is applicable in the semiconductor / display field.

[0095] The silicone adhesive maintains flexibility even at high temperatures and provides excellent insulation properties and moisture resistance. In one or more embodiments, the silicone adhesive is "Dow Corning DOWSIL TM It may include "3140 RTV" and "Momentive TSE 392".

[0096] Dow Corning DOWSIL TM "3140 RTV" has a heat resistance of approximately -55°C to approximately 200°C, excellent insulation performance and moisture resistance, and low stress properties that absorb the difference in thermal expansion between metal and ceramic surfaces, making it suitable for application in electronic components or vacuum chambers. "Momentive TSE 392" has a continuous operating temperature of approximately 250°C, excellent heat resistance and flexibility, and is suitable for vacuum environments due to its low outgassing characteristics, and can also be applied for electrical insulation in high-temperature environments.

[0097] Polyimide-based adhesives have excellent chemical compatibility and exhibit optimal performance in high-temperature environments. In one or more embodiments, the polyimide adhesive may comprise "DuPont Pyralux® LF Prepreg (polyimide-based adhesive film)".

[0098] "DuPont Pyralux® LF Prepreg" has heat resistance of approximately 350°C or higher, high insulation strength and low dielectric constant, excellent adhesion, and low gas emission performance, making it suitable for semiconductor / display applications.

[0099] In one or more embodiments, when using the bonding layer (130) described above, a primer layer may be provided after removing the oxide layer in the case of the metal base member (110), and plasma cleaning may be provided in the case of the ceramic plate (121). In addition, the bonding layer (130) described above mostly requires thermal curing (e.g., approximately 100°C to approximately 150°C, approximately 1 hour to approximately 2 hours). In addition, when using the bonding layer (130) in a vacuum environment, it is necessary to use it after releasing residual gas. By using such a bonding layer (130), the bonding layer (130) can directly surround the electrode layer (122).

[0100] In the manufacturing process of the substrate fixing device (100) according to the present invention, various methods may be applied to bond the electrostatic chuck (120) to the base member (110). Such bonding methods are configured to satisfy requirements such as reliability, bonding strength, thermal stability, and prevention of outgassing under the usage environment of the substrate fixing device (100), i.e., high temperature and high vacuum conditions.

[0101] The method of directly bonding the electrostatic chuck (120) to the base member (110) using the bonding layer (130) mainly uses thermal, physical, and chemical methods, and each method can be appropriately selected to optimize bonding performance.

[0102] In one or more embodiments, a heat press bonding method may be applied. In this method, an epoxy adhesive, silicone adhesive, polyimide adhesive, etc., used as a bonding layer (130) is placed between an electrostatic chuck (120) and a base member (110), and then bonding is performed by activating the bonding layer (130) by applying a constant temperature and pressure. The bonding temperature may be applied in the range of approximately 200°C to approximately 400°C, and the pressure is adjusted in the range of approximately 1 MPa to approximately 10 MPa. The advantage of this method is that it provides uniform adhesion and buffers differences in thermal expansion to ensure long-term reliability. In particular, if a material with low outgassing characteristics is selected as the material for the bonding layer (130), stable performance can be maintained even in a vacuum environment.

[0103] In one or more embodiments, a vacuum heat bonding method may be applied, which can be utilized to remove bubbles and impurities that may occur during the bonding process and to maximize the adhesion of the bonding layer. This method provides the effect of removing residual gas inside the bonding layer (130) and minimizing outgassing by activating the surface of the bonding layer (130) in a vacuum environment before bonding and then performing heat bonding at a high temperature. This method is particularly advantageous in processes requiring an ultra-clean environment, such as semiconductor and display manufacturing.

[0104] In one or more embodiments, a plasma surface activation and bonding method may be applied, which is a method in which the surfaces of the electrostatic chuck (120) and the base member (110) are activated through plasma treatment and then bonded before applying the bonding layer (130). By increasing the energy of the surface through plasma treatment (e.g., Ar, O2 plasma), the adhesion with the bonding layer (130) can be improved. This method has the advantage of enabling bonding at low temperatures, allowing it to be applied to heat-sensitive members, and enabling high-strength bonding.

[0105] In one or more embodiments, a chemical bonding method is also possible, which induces a chemical bond between the electrostatic chuck (120) and the base member (110) using a silane coupling agent and a polymer-based bonding agent. This method can be carried out mainly at low temperatures and maintains excellent flexibility and chemical resistance even after bonding. In particular, the method using a silane coupling agent provides excellent performance in bonding between ceramics and metals.

[0106] In the present invention, various methods of bonding the electrostatic chuck (120) to the base member (110) using a bonding layer (130) may be applied, and each method may be selectively utilized depending on the final use and application environment of the substrate fixing device (100). Thermal compression and vacuum thermal bonding methods are suitable for ensuring reliability in high-temperature environments, while plasma activation and chemical bonding methods are advantageous in processes requiring precise bonding at low temperatures. Therefore, by applying these various bonding methods, the present invention can maximize the performance and durability of the substrate fixing device (100).

[0107] In this way, the substrate fixing device (100) according to the present invention comprises a base member (110), an electrostatic chuck (120), and a bonding layer (130), thereby providing precise fixing of the substrate and process stability. The electrostatic chuck (120) includes a ceramic plate (121) and an electrode layer (122) provided on the ceramic plate (121), and the bonding layer (130) can maintain high reliability by robustly and directly bonding the ceramic plate (121) and the electrode layer (122) onto the base member (110). Through these structural features, the present invention can exhibit stable substrate fixing performance even in high temperature and vacuum environments, and can effectively disperse mechanical and thermal stress that may occur during the process.

[0108] The ceramic plate (121) provides high thermal stability and excellent insulation performance, thereby improving durability in a high-temperature plasma environment. In addition, the electrode layer (122) formed on the ceramic plate (121) forms a uniform electrostatic field to allow for precise fixing of the substrate and provides uniform chucking force even in high-speed processes. In particular, by optimizing the method of forming the electrode layer (122) (PVD, plasma spraying, screen printing, etc.), low surface resistance and uniform conductivity can be secured, thereby minimizing electrical noise that may occur during the process.

[0109] The bonding layer (130) firmly bonds the ceramic plate (121) and the electrode layer (122) to the base member (110) and buffers the difference in thermal expansion that may occur during the bonding process, thereby maintaining long-term structural stability. The material of the bonding layer (130) can be selected to have low outgassing characteristics, which prevents contamination in a vacuum environment and further improves process reliability. In addition, the uniform bonding performance of the bonding layer (130) enables the alleviation of thermal and mechanical stress between the electrostatic chuck (120) and the base member (110), and prevents minute deformation of the substrate during the process, thereby satisfying high-precision process requirements.

[0110] In one or more embodiments, the bonding layer (130) may further include nanofillers, such as ceramic fillers or metal fillers, to improve thermal conductivity. In one or more embodiments, the average size of the nanofillers may be approximately 1 nm to approximately 10 µm. In one or more embodiments, the weight (wt%) of the nanofillers may be approximately 5 wt% to approximately 95 wt%. If the weight of the nanofillers is less than approximately 5 wt%, the thermal conductivity may be lower than the target value. If the weight of the nanofillers is greater than approximately 95%, the viscosity may be relatively high, making it difficult to spray / apply the adhesive.

[0111] In one or more embodiments, the thickness of the bonding layer (130) may be approximately 1 μm to approximately 100 mm. If the thickness of the bonding layer is less than approximately 1 μm, the thermal conductivity is excellent but the thermal diffusion performance is poor, so the thermal uniformity of the ceramic plate (121) may be low. If the thickness of the bonding layer is greater than approximately 100 mm, the thermal diffusion performance is excellent and the thermal uniformity of the ceramic plate (121) may be high but the thermal conductivity may be low.

[0112] In one or more embodiments, the nanofiller may comprise beryllium oxide (CTE: 8) and / or aluminum oxide (CTE: 7.3). In one or more embodiments, the nanofiller may comprise a material (ceramic) similar to or the same as the ceramic plate (121).

[0113] In one or more embodiments, the filler may include AlN, SiC, or Al2O3, and the bonding layer containing these may have a coefficient of thermal expansion between the base member and the ceramic plate, thereby preventing various problems caused by differences in the coefficient of thermal expansion.

[0114] In one or more embodiments, the bonding layer (130) may include a sheet-type bonding material or a double-sided adhesive tape. For example, for a double-sided adhesive tape usable in a high-temperature environment, it is important to select a product with excellent heat resistance.

[0115] For example, double-sided adhesive tape is 3M TM It may include ultra-high heat-resistant double-sided tape 9077, 3M 9082 high-heat-resistant transfer double-sided tape, or high-temperature Kapton double-sided adhesive tape. 3M TM The ultra-high heat-resistant double-sided tape 9077 can maintain continuous adhesion even in high-temperature environments up to 260°C. The 3M 9082 high-heat transfer double-sided tape can provide short-term heat resistance up to 280°C. Additionally, the high-temperature Kapton double-sided adhesive tape can be used without deformation up to 400°C, with an optimal operating temperature of approximately 230°C. Since these high-temperature double-sided tapes each have different heat resistance characteristics, you can select the product best suited for the application environment.

[0116] The substrate fixing device (100) according to the present invention maximizes the fixing force and durability of the electrostatic chuck (120) and improves the bonding strength with the base member (110) to provide long-term stability. In addition, by ensuring uniformity of electrostatic chucking performance, the yield in semiconductor and display manufacturing processes can be improved, and reliable performance in high temperature and high vacuum environments can be provided while maintaining a lightweight structure.

[0117] In one or more embodiments, each ceramic plate (121) may include a groove (124) provided along its circumference. Additionally, a plurality of electrostatic chucks (120) may be joined to each other in a horizontal direction by filling the groove (124) with a bonding layer (140). The groove (124) may include or be referred to as a trench, channel, or groove.

[0118] As described above, the ceramic plate (121) can be completed through a weighing step, a mixing step, a drying step, a crushing step, a calcining step, a forming step, and a sintering step, and subsequently, the ceramic plate (121) may include a groove (124) provided along the circumference as described above.

[0119] Additionally, by filling the groove (124) with a bonding layer (140), a plurality of ceramic plates (121) can be bonded to each other in a horizontal direction. In one or more embodiments, the bonding layer (140) can be filled and coated into the groove (124) by an atmospheric pressure plasma spray method. As described above, atmospheric pressure plasma spray is a surface treatment process that attaches the bonding layer (140) using high-temperature plasma gas; this process is carried out at atmospheric pressure and can coat various metals, ceramics, composite materials, etc. This APS method can form a bonding layer (140) with excellent adhesion to the groove (124) of adjacent ceramic plates (121) without high heat or adhesive.

[0120] That is, in order to form a bonding layer (140) with excellent adhesion to the groove (124) of the ceramic plate (121), various surface coating technologies such as aerosol deposition, arc spray, high-speed oxygen fuel spray, cold spray, and flame spray can be applied in addition to atmospheric pressure plasma spray, and these methods are effective for forming a bonding layer on various substrates such as ceramics and metals, and each method can be optimized for a specific application environment by controlling the heat source, spray speed, and coating thickness.

[0121] For example, Atmospheric Plasma Spray (APS) is a method that uses high-temperature plasma to melt and accelerate bonding materials for deposition on a surface, providing high adhesion and a uniform coating layer. This method is primarily used in environments requiring high-temperature resistance and enables the formation of thick coatings with excellent mechanical strength.

[0122] Aerosol deposition (AD) is a method of attaching ultrafine powder to a substrate by spraying it at high speed, enabling the formation of a coating layer with excellent adhesion even at relatively low temperatures. This method is advantageous for forming coating layers with high density and microstructure, and is applicable even to brittle materials such as ceramics.

[0123] Arc spray is a method that melts metal using an electric arc generated between two metal wire electrodes and sprays the molten particles onto a substrate using a high-speed airflow. This method is economical and can rapidly form thick coatings, but the surface roughness may be high, which may require post-processing.

[0124] High Velocity Oxygen Fuel (HVOF) spraying is a method that injects coating particles at high speeds through the combustion of fuel and oxygen, capable of forming a dense coating layer with very high adhesive strength. This method is particularly useful in environments requiring wear resistance and corrosion resistance.

[0125] Cold spray is a method that uses a supersonic airflow to collide powder particles with a substrate without heating, providing high adhesion while minimizing thermal effects. This method can be applied to heat-sensitive materials and forms a coating layer free from cracking and oxidation.

[0126] Flame spray is a method that uses a flame generated by burning fuel gas to melt and spray bonding materials, and it is a relatively simple and cost-effective method. However, the adhesion and uniformity of the coating may be somewhat lower compared to other high-temperature spray methods.

[0127] By applying such various coating technologies, the present invention can form a uniform bonding layer with excellent adhesion in the grooves of the ceramic plate, thereby improving the structural stability and durability of the substrate fixing device.

[0128] In one or more embodiments, the bonding layer (140) may be provided as a ceramic. In one or more embodiments, the bonding layer (140) may comprise zirconia (ZrO2), beryllium oxide (BeO), aluminum oxide (Al2O3), aluminum nitride (AlN), silicon carbide (SiC), silicon nitride (Si3N4), or aluminum titanate (Al2TiO5). In one or more embodiments, the bonding layer (140) may further comprise yttrium oxide (Y2O3), yttrium oxide (YOF), or YF3.

[0129] In this way, the present invention can provide a large-area electrostatic chuck by horizontally bonding and fixing a plurality of electrostatic chucks (120) on a single base member (110), and also provide a large-area bonded substrate fixing device (100) having excellent flatness.

[0130] FIG. 3 is a flowchart illustrating a method for manufacturing a large-area bonded substrate fixing device (100) according to an embodiment of the present invention. As shown in FIG. 3, the method for manufacturing a substrate fixing device (100) that fixes a substrate by electrostatic force according to an embodiment of the present invention may include a step of providing a ceramic plate having a groove (S1), a step of completing an electrostatic chuck by providing an electrode layer on the ceramic plate (S2), a step of attaching a plurality of electrostatic chucks using a bonding layer on a base member (S3), and a step of completing a large substrate fixing device by forming a bonding layer in the groove of the ceramic plate (S4).

[0131] FIGS. 4a to 4d are cross-sectional views illustrating a method for manufacturing a large-area bonded substrate fixing device (100) according to an embodiment of the present invention. Here, since the types of materials and manufacturing methods have been described above, redundant descriptions are omitted.

[0132] As illustrated in FIG. 4a, first, in the step (S1) of providing a ceramic plate having a groove, a ceramic plate (121), which is a major component of an electrostatic chuck for fixing a substrate by electrostatic force, is provided. The ceramic plate (121) is formed from a ceramic material with excellent heat resistance and insulation properties, such as alumina (Al2O3), aluminum nitride (AlN), and silicon carbide (SiC), and is manufactured through a sintering process under preset temperature, time, and pressure conditions. Additionally, a groove (124) is formed along the perimeter of the ceramic plate (121), and the groove (124) is utilized as a space for filling a bonding layer (140) between electrostatic chucks in a subsequent process. The shape and size of the groove (124) are precisely machined to maximize the adhesion of the bonding layer (140) and are designed to provide uniform bonding performance and high mechanical strength.

[0133] As illustrated in FIG. 4b, in the next step (S2) of completing the electrostatic chuck by providing an electrode layer on a ceramic plate, an electrode layer (122) made of aluminum (Al), copper (Cu), molybdenum (Mo), silver (Ag), tungsten (W), titanium (Ti), or a conductive oxide is formed on the lower surface of the ceramic plate (121). The electrode layer can be formed using at least one of various methods such as sputtering, electron beam evaporation (E-Beam Evaporation), chemical vapor deposition (CVD), screen printing, inkjet printing, dispensing, plasma spraying, electroplating, and laser ablation. The pattern of the electrode layer is precisely formed to ensure a uniform distribution of electrostatic force, thereby designing it to enable stable chucking of the substrate. In one or more embodiments, the ceramic plate (121) and the electrode layer (122) may be wrapped with a bonding layer (130). The bonding layer (130) may include an epoxy-based, silicone-based, or polyimide-based bonding material having heat resistance of approximately 200°C to approximately 400°C.

[0134] As illustrated in FIG. 4c, in the next step (S3) of attaching a plurality of electrostatic chucks using a bonding layer on a base member, a plurality of electrostatic chucks (120) are precisely attached to the base member (110). The base member (120) may be composed of ceramic, aluminum, titanium, etc., and a heating line may be provided in the upper region and a cooling line in the lower region. The bonding layer (130) may use an epoxy-based, silicone-based, or polyimide-based adhesive to buffer the difference in thermal expansion between the ceramic plate (121) and the electrode layer (122) and the base member (110) and to provide strong bonding strength. Methods for forming the bonding layer may include vacuum heat pressing, plasma surface treatment, primer coating, ultrasonic bonding, etc., and an anti-outgassing coating layer may be additionally applied to ensure reliability in a vacuum environment.

[0135] As illustrated in FIG. 4d, in the final step (S4) of completing a large substrate fixing device by forming a bonding layer in the groove of the ceramic plate, a bonding layer (140) for integrating a plurality of electrostatic chucks (120) is formed within the groove (124). The bonding layer (124) can be uniformly provided not only in the groove but also over the entire upper surface of the ceramic plate (121), and various techniques such as atmospheric pressure plasma spray, aerosol deposition, arc spray, high-speed oxygen fuel spray, cold spray, and flame spray can be applied as methods for forming the bonding layer.

[0136] The Atmospheric Pressure Plasma Spray (APS) method secures high adhesion by using high-temperature plasma to melt and accelerate bonding layer materials and then filling them into grooves, offering excellent thermal stability and wear resistance. The Aerosol Deposition method fills grooves by high-speed spraying of nano-sized ultrafine particles, characterized by its ability to form a uniform and dense bonding layer even at low temperatures. The Arc Spray method utilizes an arc discharge generated between two metal wire electrodes to melt and spray metal particles, enabling the rapid formation of a thick bonding layer. Furthermore, the High-Speed ​​Oxygen Fuel Spray method provides a bonding layer with excellent adhesion and high density by spraying particles at ultra-high speeds through the combustion of fuel and oxygen, while the Cold Spray method achieves strong adhesion while maintaining low thermal impact by using a supersonic airflow to collide particles with a substrate without heating. The Flame Spray method allows for the formation of a low-cost bonding layer through a simple process using a flame generated by burning fuel gas. The bonding layers formed in this manner ensure structural integrity between electrostatic chucks and provide high mechanical stability and reliability through the uniform filling of the bonding layer. In one or more embodiments, a grinding process is performed on the ceramic plate (121) and the bonding layer (140) after this process to improve the flatness of the upper surface of the electrostatic chuck (120). The upper surface of the electrostatic chuck (120), i.e., the ceramic plate (121), can be controlled to have a flatness of approximately 1 μm to approximately 30 μm.

[0137] In this way, the method for manufacturing a substrate fixing device according to the present invention effectively combines a ceramic sintering method and a bonding layer method, thereby providing a highly reliable structure capable of firmly and uniformly fixing a large-area substrate, and thereby maximizing usability in semiconductor and display manufacturing processes.

[0138] FIGS. 5 to 11 are cross-sectional views illustrating a large-area bonded substrate fixing device according to another embodiment of the present invention.

[0139] As illustrated in FIG. 5, in a large-area bonded substrate fixing device (200) according to an embodiment of the present invention, the bonding layer (240) may be provided not only in the groove (124) but also on the upper side of the ceramic plate (121) which is outside the groove (124). That is, the bonding layer (240) may be provided not only in the groove (124) corresponding to the boundary region between the ceramic plates (121) but also on the entire upper side of the ceramic plate (121), and the upper side of the bonding layer (240) has a flatness of approximately 1 μm to 30 μm. Here, the bonding layer (240) may share the characteristics of the high-resistance ceramic, high-dielectric constant ceramic, or low-resistance ceramic described above. For example, a low-resistance ceramic sintered body (e.g., with a resistance value of 10 12 A low-resistance junction layer or low-resistance coating layer with lower resistance (e.g., resistance value of 10) on top of Ω·cm) 11 By applying Ω·cm), an antistatic function can be manifested through the low-resistance junction layer and de-chucking performance can be improved. This embodiment can be applied to all other embodiments of the present invention as well.

[0140] The large-area bonded substrate fixing device (300) illustrated in FIG. 6 may be similar to the substrate fixing device (200) illustrated in FIG. 5, except that an outgassing prevention coating layer (310) is further provided. Thus, the differences are mainly described.

[0141] The large-area bonded substrate fixing device (300) according to the present invention further improves reliability in a vacuum environment by additionally including an outgassing prevention coating layer (310) in the portion of the bonding layer (130) that is exposed to the outside through the area between the base member (110) and the ceramic plate (121). For example, the outgassing prevention coating layer (310) includes yttrium oxide (Y2O3), yttrium fluoride (YOF), YF3, or a rare earth series oxide, thereby effectively blocking gas emissions that may occur from the bonding layer (130) and ensuring long-term performance stability of the substrate fixing device (300).

[0142] Yttrium oxide has excellent chemical resistance and plasma resistance, and provides excellent durability in high-temperature and high-vacuum process environments such as plasma etching and thin film deposition. In the present invention, by using this yttrium oxide to protect the exposed area of ​​the bonding layer (130), contamination within the vacuum chamber can be minimized and the precise fixation of the substrate can be maintained.

[0143] The above-mentioned anti-outgassing coating layer (310) can be formed using a technique such as aerosol deposition, thereby ensuring high adhesion and a uniform coating thickness. This coating method prevents cracking caused by differences in the coefficient of thermal expansion of the bonding layer (130) and allows stable physical and chemical properties to be maintained even during long-term use.

[0144] In one or more embodiments, the aerosol deposition can form a uniform and dense coating layer using ultrafine particles of approximately 1 μm or less, resulting in excellent gas penetration prevention and vacuum maintenance performance. Plasma spraying can form a coating layer at high speed, making it applicable to large parts and providing high thermal stability. However, due to the difference in the coefficient of thermal expansion between the bonding layer (130) and the yttrium oxide coating layer (e.g., the bonding layer is approximately 1 ppm / °C to approximately 50 ppm / °C, and Y2O3 is approximately 8 ppm / °C), there is a possibility of thermal stress and cracking, so an intermediate layer (e.g., Al2O3, TiO2, etc.) may be further interposed. Additionally, while aerosol deposition allows for coating at low temperatures, temperature control is required during plasma spraying so as not to exceed the heat resistance of the bonding layer (130). In one or more embodiments, it is preferable to apply the coating layer uniformly with a thickness of approximately 1 μm to approximately 50 μm. Furthermore, when a multilayer coating (e.g., Y2O3 / TiO2 composite layer) is applied instead of a single layer of Y2O3, adhesion can be improved and thermal stress alleviated. In addition, initial outgassing can be removed through vacuum bake-out treatment after coating.

[0145] Accordingly, the present invention can achieve technical effects such as maximizing the reliability of the substrate fixing device (300), preventing contamination in a vacuum environment, and reducing maintenance costs by forming an outgassing prevention coating layer (310) on the exposed area of ​​the bonding layer (130). This embodiment may also be applied to other embodiments of the present invention.

[0146] The bonded large-area substrate fixing device (400) illustrated in FIG. 7 may be similar to the substrate fixing device (200) illustrated in FIG. 5, except that it further includes a plurality of support members (410, 420). Therefore, the differences are mainly described.

[0147] The substrate fixing device (400) according to the present invention may additionally include a plurality of support members (410, 420) that penetrate the bonding layer (130) between the upper side of the base member (110) and the lower side of the ceramic plate (121) in order to strengthen the structural stability between the base member (110) and the ceramic plate (121) and to improve the reliability of the bonding layer (130). The support member (410) may be formed to extend from the base member (110) toward the ceramic plate (121) or, conversely, from the ceramic plate (121) toward the base member (110), thereby strengthening the structural stability of the bonding layer (130) and increasing its durability against the external environment. Furthermore, due to this structure, the distance from the base member (110) to the ceramic plate (121) may be uniform in all areas.

[0148] In one or more embodiments, the support member (420) positioned at the outermost of the plurality of support members may serve to prevent the bonding layer (130) from being exposed to the external environment. Specifically, the outermost support member (420) may provide a shielding function to prevent the bonding layer (130) from being exposed to the outside by joining the outermost portions of the base member (110) and / or the ceramic plate (121) to each other. This configuration prevents deformation and peeling of the bonding layer (130) due to thermal and mechanical stress, and contributes to preventing contamination from the external environment (high temperature, plasma, vacuum environment, etc.) and ensuring the long-term reliability of the substrate fixing device (400).

[0149] Additionally, the bonding layer (130) may be provided by filling the space between the base member (110) and the ceramic plate (121), which are spaced apart at regular intervals by a plurality of support members (410). In the present invention, to solve the problem of uneven filling that may occur when the bonding layer (130) is filled, the bonding layer (130) may be configured to penetrate and be distributed uniformly into the fine gap between the base member (110) and the ceramic plate (121) by utilizing the capillary phenomenon. Through this, the bonding strength is improved by the uniform formation of the bonding layer (130), and the structural stability and durability of the substrate fixing device (400) can be increased.

[0150] According to one or more embodiments, an exhaust hole (not shown) may be formed in the outermost support member (420) to enable smooth discharge of air present inside during the filling process of the bonding layer (130) and to maximize the filling efficiency of the bonding layer (130). Through the exhaust hole, the bonding layer (130) can completely fill the microspace between the base member (110) and the ceramic plate (121), thereby preventing bonding defects caused by air trapping and improving bonding strength and heat transfer characteristics. Through this configuration, the present invention can maintain high reliability even during long-term use in high temperature and high vacuum environments.

[0151] Accordingly, the substrate fixing device (400) according to the present invention includes a plurality of support members (410, 420) to provide a strong bond between the base member (110) and the ceramic plate (121) and an accurate mutual separation distance, and can maximize durability and reliability by uniform filling of the bonding layer (130) and prevention of external exposure, and can provide optimal performance in high-precision process environments such as semiconductor and display manufacturing.

[0152] In this way, the substrate fixing device (100, 200, 300, 400) according to the present invention is designed to maximize substrate fixing performance in a high temperature and high vacuum environment through an optimized configuration of a base member (110), an electrostatic chuck (120), and a bonding layer (130). The electrostatic chuck (120) includes a ceramic plate (121) with excellent flatness and an electrode layer (122), thereby enabling the substrate to be fixed with a uniform electrostatic force and maintaining high stability even under thermal and mechanical stresses occurring during the process. The bonding layer (130) buffers the difference in thermal expansion that may occur during the bonding of heterogeneous materials between the base member (110) and the ceramic plate (121), and by additionally forming an anti-outgassing coating layer (310), it is possible to prevent contamination in a vacuum environment and ensure long-term reliability.

[0153] In particular, the present invention improves bonding quality by introducing a plurality of support members (410, 420) to reinforce the structural rigidity between the base member (110) and the ceramic plate (121) and to induce uniform filling of the bonding layer (130). In addition, the outermost support member (420) prevents the bonding layer (130) from being exposed to the outside and provides a hole for internal air discharge, thereby maximizing the filling efficiency of the bonding layer (130). This configuration extends the lifespan of the substrate fixing device (400) and minimizes maintenance even in high temperature and plasma environments.

[0154] Consequently, the substrate fixing device (400) according to the present invention is optimized for application in environments requiring high precision and reliability, such as semiconductor and display manufacturing processes, by providing excellent flatness, chemical resistance, and heat resistance, and can contribute to improving process yield and productivity. This embodiment may also be applied to other embodiments of the present invention.

[0155] As illustrated in FIG. 8, a large-area bonded substrate fixing device (500) according to an embodiment of the present invention may include a base member (110), a lower bonding layer (520), a polyimide electrostatic chuck (530), an upper bonding layer (540), and a ceramic plate (121). Here, the base member (110), the ceramic plate (121), and the bonding layer (140) have been described above, so their description is minimized. Additionally, the lower bonding layer (520) and the upper bonding layer (540) may have similar or identical electrical / thermal properties, so they are described together. The lower bonding layer (520) and / or the upper bonding layer (540) may share all the features of the bonding layer (130) described above.

[0156] Since the lower bonding layer (520) serves to bond the polyimide electrostatic chuck (530) to the base member (110) and the upper bonding layer (540) serves to bond the polyimide electrostatic chuck (530) to the ceramic plate (121), the lower bonding layer (520) and the upper bonding layer (540) must satisfy requirements such as high temperature stability, insulation performance, chemical resistance, and vacuum resistance.

[0157] For example, the bonding layer needs to have heat resistance of approximately 200°C to approximately 400°C so as to be maintained stably in a high-temperature environment, have a thermal expansion coefficient suitability to minimize the difference in thermal expansion between the base member (110), the polyimide electrostatic chuck (530), and the ceramic plate (121), have chemical resistance that is resistant to plasma and corrosive gases (NF3, CF₄, etc.), and also have high mechanical strength to maintain high adhesion and wear resistance.

[0158] In one or more embodiments, to satisfy these characteristics, the bonding layer may include an epoxy-based, silicone-based, or polyimide-based bonding material, which may share all the characteristics of the bonding layer (130) described above, so a description is omitted.

[0159] In one or more embodiments, when using the bonding layer described above, a primer layer may be provided after removing the oxide layer in the case of the metal base member (110), and plasma cleaning may be provided in the case of the ceramic plate (121). Additionally, the bonding layer described above generally requires thermal curing (e.g., approximately 100°C to approximately 150°C, approximately 1 hour to approximately 2 hours), and the thermal expansion characteristics of the polyimide electrostatic chuck (530) must be taken into account during high-temperature curing. Furthermore, when using the bonding layer in a vacuum environment, it is necessary to use it after releasing residual gas.

[0160] In one or more embodiments, to prevent outgassing of the bonding layer, the surface of the bonding layer may be further provided with an outgassing prevention coating layer by aerosol deposition or atmospheric pressure plasma spraying with ceramic powder containing yttrium oxide (e.g., Y2O3). In one or more embodiments, the coating layer may also be provided on the surface of a polyimide electrostatic chuck (530) exposed to a vacuum chamber.

[0161] As such, the yttrium oxide coating layer is a very effective method for preventing outgassing and improving durability of the bonding layer (520, 540) or the polyimide electrostatic chuck (530), and it is particularly desirable to form a uniform coating at a low temperature through an aerosol deposition process.

[0162] In one or more embodiments, the bonding layer (520, 540) may further include nanofillers, such as ceramic fillers or metal fillers, to improve thermal conductivity. Since these fillers are also similar or identical to the fillers contained in the bonding layer (130) described above, further description is omitted. Likewise, the bonding layer (520, 540) may be replaced with a sheet-type double-sided adhesive.

[0163] A polyimide electrostatic chuck (530) is provided on a lower bonding layer (520) to fix a substrate by electrostatic force. The polyimide electrostatic chuck (530) may include a polyimide insulating layer (531) and an electrode layer (532). The polyimide insulating layer (531) is a base insulating material forming the electrostatic chuck, and polyimide provides excellent electrical insulation and heat resistance (e.g., 400°C or higher). For example, polyimide has excellent chemical stability in plasma processes. The electrode layer (532) is for fixing the substrate. For example, it may be composed of two electrodes (bipolar type) or one electrode (monopolar type). In one or more embodiments, the electrode layer (532) may include a conductive material such as aluminum, copper, molybdenum, silver, tungsten, titanium, or a conductive oxide.

[0164] The operating principle of the polyimide electrostatic chuck (530) utilizes the generation of electrostatic force based on Coulomb's law. When a high voltage (e.g., hundreds to thousands of volts) is applied to the electrode layer (532), an electrostatic force is formed. This causes induced charges to be generated between the wafer and the electrostatic chuck, resulting in an attractive force (electrostatic force). The electrostatic force keeps the wafer / display flat, enabling uniform contact compared to a vacuum chuck. It also serves as a fixing mechanism to prevent the wafer from shaking during plasma processes. Meanwhile, after the process is completed, the power is cut off or a reverse voltage is applied to remove the accumulated charge. Any residual charge remaining on the surface must be completely removed through a discharge process so that the wafer can be safely detached.

[0165] In one or more embodiments, the polyimide insulating layer (531) has high temperature resistance that maintains performance without deformation even in high temperature environments (e.g., approximately 300°C to approximately 400°C), excellent insulation that minimizes leakage current occurring during processing, chemical stability that maintains durability even in plasma and corrosive gas environments, and also has lightweight and flexible properties that allow for precise substrate alignment and stable wafer maintenance.

[0166] As such, the polyimide insulating layer (531) is a high-performance polymer that provides excellent thermal, mechanical, and electrical properties, and when used for an electrostatic chuck, high temperature resistance and insulating properties are required. Below, polyimide materials, thicknesses, and properties suitable for an electrostatic chuck are described.

[0167] The polyimide insulating layer (531) preferred for use as an electrostatic chuck may include "Kapton (DuPont)," "Ultem (SABIC)," and "Vespel (DuPont)." "Kapton (DuPont)" may mainly include pentite-based polyimide (PMDA-ODA). It has heat resistance with a continuous operating temperature of approximately 400°C or higher, an insulating strength of approximately 250 kV / mm or higher, a dielectric constant of approximately 3.5 (at 1 kHz), and is suitable for semiconductor / display manufacturing due to its low gas emission rate and suitability for vacuum processes. "Ultem (SABIC)" mainly includes polyetherimide (PEI), has a continuous operating temperature of approximately 200°C or higher, excellent mechanical strength, and excellent chemical resistance and insulating properties, making it suitable as a base layer and insulating layer for an electrostatic chuck. Vespel (DuPont) mainly comprises polyimide / polyamide composites, which have high wear resistance, excellent mechanical properties and a low coefficient of thermal expansion, and can be used continuously up to approximately 288°C, making them suitable for high-temperature vacuum environments.

[0168] In one or more embodiments, the thickness of the polyimide insulating layer (531) varies depending on the application environment, but may have a thickness range of approximately 10 μm to approximately 500 μm when applied as an electrostatic chuck. Since the thickness of the polyimide electrostatic chuck (530) affects the uniformity of electrostatic force, insulation performance, heat dissipation performance, etc., it may be selected according to the requirements of the application process. For example, the characteristics required for the polyimide insulating layer (531) are as follows.

[0169] Characteristic Values ​​(Typical Range) Description Pyrolysis Temperature: 450 to 600 °C (Maintains amorphous state) Polyimide pyrolyzes without melting Continuous Use Temperature: 250 °C to 400 °C Long-term Use Temperature Range Dielectric Constant: 3.0 to 3.6 (at 1 kHz) A critical factor determining insulation performance Dielectric Breakdown Strength: 200 to 300 kV / mm Electrical Insulation Performance Coefficient of Thermal Expansion: 4 to 80 ppm / °C Excellent Thermal Stability Hygroscopicity: 1.0% or less Excellent Resistance to Moisture Mechanical Strength Tensile Strength: 100 to 200 MPa Provides high strength and flexibility

[0170] In this way, the polyimide insulating layer (531) has high thermal decomposition temperature, maintaining performance even in extreme environments to have high temperature stability, and provides excellent insulation performance by offering low dielectric constant and high insulation strength, and maintains durability against plasma and corrosive gases to have chemical stability, and has lightweight and flexible properties. However, as the thickness of the polyimide insulating layer (531) increases, heat dissipation becomes difficult, so it needs to be configured together with a cooling system. In the present invention, the lower base member (110) and the upper ceramic plate (121) help with cooling performance. In one or more embodiments, the electrode layer (532) can provide the metal or alloy on the polyimide insulating layer (531) in various ways such as sputtering, electroless plating, electroplating, deposition, and electronic printing. In one or more embodiments, the electrode layer (532) can improve compatibility with the polyimide insulating layer (531) by providing conductive ink on the polyimide insulating layer (531) in a manner such as spraying or coating. The upper bonding layer (540) serves to bond the polyimide electrostatic chuck (530) and the ceramic plate (121). In particular, the upper bonding layer (540) covers the polyimide insulating layer (531) and the electrode layer (532) and is bonded to the ceramic plate (121). That is, the lower bonding layer (520) described above serves to bond the polyimide insulating layer (531) and the base member (110), and the upper bonding layer (540) serves to bond the polyimide insulating layer (531) and the electrode layer (532) together to the ceramic plate (121). When a multilayer structure of the base member (110), polyimide electrostatic chuck (530), and ceramic plate (121) is applied in the substrate fixing device (500) according to the present invention, there are various important technical advantages / effects. These are explained in terms of performance, process stability, mechanical and thermal properties as follows.

[0171] First, the substrate fixing device (500) according to the present invention has thermal stability and uniform temperature distribution characteristics. That is, thanks to the excellent thermal conductivity and flatness of the ceramic plate (121), a uniform heat distribution is provided to the substrate, and accordingly, the temperature deviation during heating / cooling of the wafer / display is minimized. In addition, the polyimide insulating layer (531) acts as a thermal buffer between the base member (110) and the ceramic plate (121), thereby relieving stress caused by the difference in thermal expansion (CTE mismatch). Furthermore, stable performance is maintained even in high-temperature processes due to the high heat resistance of the polyimide (e.g., approximately 400°C or higher).

[0172] Second, the substrate fixing device (500) according to the present invention enables the maintenance of substrate flatness and precision machining. That is, the ceramic plate (121) provides excellent flatness, allowing the substrate to be fixed precisely. When fixing the substrate, deformation of the substrate due to surface non-uniformity is prevented, and thus pattern precision is improved in the lithography and deposition processes. In addition, it is suitable for processing ultra-thin wafers due to fine thickness adjustment and high strength characteristics.

[0173] Third, the substrate fixing device (500) according to the present invention has the effect of improving electrostatic chucking performance. That is, the excellent insulation properties of polyimide and the high dielectric constant of ceramic are combined to enable a uniform distribution of electrostatic force. In addition, the electrostatic chuck surface is covered with ceramic, thereby reducing particle contamination and providing a uniform chucking force during electrostatic fixing. Furthermore, the ceramic plate (121) optimizes the contact area with the substrate for electrostatic chucking, thereby improving adsorption uniformity and detachment.

[0174] Fourth, the substrate fixing device (500) according to the present invention has improved chemical resistance and wear resistance. That is, the surface of the ceramic plate (121) has excellent chemical resistance against plasma processes and corrosive gases (CF4, SF6, etc.). In addition, polyimide has excellent plasma resistance, so there is little surface damage even during long-term use, and accordingly, the lifespan of the electrostatic chuck is extended. Furthermore, due to the low friction coefficient of the ceramic, particle generation can be minimized during wafer processing.

[0175] Fifth, the substrate fixing device (500) according to the present invention is lightweight and has improved mechanical stability. That is, the lightweight characteristics of polyimide and the high strength of ceramic are combined to provide excellent mechanical stability, and vibration is minimized even during acceleration / deceleration of semiconductor / display equipment. In addition, stable wafer holding is possible even during high-speed wafer loading / unloading processes. Furthermore, the ceramic is not directly subjected to mechanical stress, and the polyimide acts as a buffer, thereby increasing fatigue life.

[0176] Sixth, the substrate fixing device (500) according to the present invention has vacuum compatibility and a contamination minimization effect. That is, the ceramic plate (121) has almost no outgassing, thereby minimizing the emission of contaminants within the vacuum chamber. In addition, since polyimide has low gas emission characteristics, it exhibits stable performance even in vacuum processes. Furthermore, it can suppress nano-level contamination, making it suitable for advanced semiconductor and display processes.

[0177] Seventh, the substrate fixing device (500) according to the present invention has the effects of ease of maintenance and modularity. That is, it is composed of a modular structure (base member (110) + polyimide electrostatic chuck (530) + ceramic plate (121)), so that if a specific layer is damaged, partial replacement is possible, thereby reducing maintenance costs. In addition, the thickness of the base member (110) (metal / ceramic) and the polyimide electrostatic chuck (530) can be adjusted to suit various processes, making process-customized design easy.

[0178] Eighth, the substrate fixing device (500) according to the present invention has improved discharge characteristics and a substrate protection effect. Thanks to the insulating properties of polyimide, it has an effect of preventing unnecessary electrostatic discharge. In addition, the ceramic plate suppresses the increase in surface roughness of the electrostatic chuck, thereby preventing the occurrence of fine scratches on the substrate and maintaining the quality of the substrate. Furthermore, it minimizes residual charge when releasing the electrostatic chuck, making wafer removal easy.

[0179] Consequently, the present invention improves process precision by enabling uniform heat distribution and stable substrate fixation through bonding a ceramic plate (121) with excellent flatness onto a polyimide electrostatic chuck (530). In addition, reliability is enhanced even in plasma and high-temperature environments due to the excellent chemical resistance of the ceramic and the insulating properties of the polyimide. Furthermore, the lifespan of the equipment can be extended by minimizing vibration and stress deformation through a lightweight structure and mechanical cushioning effect.

[0180] In other words, the present invention can provide a large-area bonded substrate fixing device (500) that can provide excellent flatness through a grinding process because the area on which a wafer or display substrate is placed is a ceramic plate (121) with high rigidity or strength rather than a polyimide electrostatic chuck (530), and excellent flatness can be provided by grinding the upper side because the ceramic plate (121) can be made thicker than the polyimide electrostatic chuck (530), and thus the chucking force can be improved while being rigid by controlling the thickness of the sintered body (121).

[0181] Furthermore, the present invention ensures excellent adhesion and durability between the polyimide electrostatic chuck, base, and ceramic plate by applying lower and upper bonding layers. In particular, by applying a plasma-resistant coating layer such as Y2O3 to minimize outgassing, contamination in vacuum environments is prevented, and long-term reliability is guaranteed. The lifespan of the substrate fixing device can be extended by mitigating thermal stress between dissimilar materials through the optimized coefficient of thermal expansion (CTE) of the bonding layer.

[0182] As illustrated in FIG. 9, the large-area bonded substrate fixing device (600) according to an embodiment of the present invention may have a bonding layer (240) provided not only in the groove (124) but also on the upper side of the ceramic plate (121) which is outside the groove (124). That is, the bonding layer (240) may be provided not only in the groove (124) corresponding to the boundary area between the ceramic plates (121) but also on the entire upper side of the ceramic plate (121), and the upper side of the bonding layer (140) has a flatness of approximately 1 μm to approximately 30 μm.

[0183] As illustrated in FIG. 10, a large-area bonded substrate fixing device (700) according to an embodiment of the present invention may be similar to the substrate fixing device (500) illustrated in FIG. 8, except that polyimide insulating layers (731, 733) are provided on both sides facing each other with respect to the electrode layer (732) and the polyimide insulating layers (731, 733) are directly bonded to a base member (110) and / or a ceramic plate (121).

[0184] As illustrated in FIG. 10, a large-area bonded substrate fixing device (700) may include a base member (110), a polyimide electrostatic chuck (730), and a ceramic plate (121). Here, the polyimide electrostatic chuck (730) is bonded to the base member (110) and serves to fix the substrate by electrostatic force, and the ceramic plate (121) is bonded to the polyimide electrostatic chuck (730) and serves to directly mount the substrate.

[0185] In one or more embodiments, the polyimide electrostatic chuck (730) may include a first polyimide insulating layer (731), an electrode layer (732) provided on the first polyimide insulating layer (731) (e.g., bottom surface), and a second polyimide insulating layer (733) covering the first polyimide insulating layer (731) and the electrode layer (732).

[0186] Here, in addition to using the bonding layer described above, the method of bonding the polyimide insulating layer (731, 733) of the polyimide electrostatic chuck (730) to the metal base member (110) or ceramic plate (121) can achieve stable bonding in high temperature and high vacuum environments by utilizing chemical, physical, and thermal processes. Representative methods are as follows.

[0187] First, there is the chemical bonding / bonding method, which induces chemical bonding between the polyimide and the surface of the metal / ceramic.

[0188] For example, there is a bonding method involving surface modification via plasma treatment, in which the polyimide and metal / ceramic surfaces are activated through plasma treatment (Ar, O2) to increase chemical affinity, and then bonded using a high-temperature press. For instance, plasma treatment increases the reactivity of the polyimide surface, and the metal / ceramic surface is cleaned and activated (plasma, chemical etching, etc.). Subsequently, bonding is performed using a heat press at approximately 250°C to approximately 350°C with a constant pressure (e.g., approximately 1 MPa to approximately 5 MPa). This method enables chemical bonding without adhesives, maintains durability even in high-temperature environments, and offers excellent vacuum compatibility.

[0189] Another example is a high-temperature press bonding method following chemical primer treatment, in which a primer capable of reacting with metals or ceramics (silane coupling agents, titanium or aluminum-based compounds) is coated onto the polyimide surface and then bonded. For example, a primer is applied (aluminum-based: Al(acac)3, silane-based: APTES), and after drying, a press is applied at approximately 150°C to approximately 250°C, and the bonding strength is checked after final curing. This method enables strong bonding due to increased surface affinity and is applicable to various metal and ceramic materials.

[0190] Next, there is a physical bonding method, which strengthens the bond through physical compression and interface processing.

[0191] An example is the vacuum hot press bonding method, which induces physical adhesion between polyimide and metal / ceramic by applying high temperature and pressure. To achieve this, the polyimide and metal / ceramic are surface-cleaned and roughened (sandblasted), and then placed in a vacuum environment (e.g., approximately 10 -3The bond is maintained by heating to approximately 300°C to approximately 450°C at a temperature of Torr or less, applying a pressure of approximately 1 MPa to approximately 10 MPa, and then cooling. This method provides stable bond strength even at high temperatures and prevents chemical contamination.

[0192] Another example is Ultrasonic Welding, which uses ultrasonic vibrations to locally heat and melt the bonding surfaces to create a bond. To achieve this, precise surface finishing and cleaning are performed on the bonding surfaces, ultrasonic vibrations of approximately 20 kHz to approximately 40 kHz are applied (e.g., amplitude of approximately 60 µm to approximately 120 µm), and local bonding is performed with a short heating time (e.g., within seconds). This method enables rapid bonding, offers excellent mechanical strength, and provides an environmentally friendly, solvent-free process.

[0193] Next, there is a thermal bonding method, which directly bonds polyimide by heating and pressing it under specific conditions.

[0194] For example, there is Direct Heat Press Bonding, which involves joining a metal / ceramic by heat pressing at a temperature exceeding the glass transition temperature (Tg) of the polyimide (e.g., approximately 400 °C or higher). To achieve this, the polyimide is preheated to approximately 350 °C to approximately 450 °C (vacuum conditions recommended), a constant pressure (e.g., approximately 3 MPa to approximately 10 MPa) is applied to the metal / ceramic member to perform the bonding, and then the stress is relieved by slowly cooling. This allows for pure bonding without additional chemicals and maintains high heat resistance.

[0195] Another example is the laser annealing bonding method, which uses a high-power laser (Excimer, CO2) to locally melt and bond polyimide with ceramic / metal surfaces. To achieve this, localized surface modification and fusion are performed through laser irradiation, and bond stabilization is achieved through rapid cooling. This enables precise and rapid bonding with minimal thermal impact.

[0196] Meanwhile, several factors must be considered when bonding polyimide to metals or ceramics.

[0197] For example, differences in coefficients of thermal expansion (CTE mismatch) must be considered. For instance, since ceramics (Al2O3: approximately 5 ppm / °C to approximately 8 ppm / °C) versus polyimide (approximately 30 ppm / °C to approximately 50 ppm / °C), the use of an intermediate layer to relieve mechanical stress may be necessary. Additionally, a cleanroom environment must be maintained during the manufacturing process, as fine particles or contaminants can cause bonding failures. Furthermore, evaluating bonding reliability through outgassing tests is essential.

[0198] In this way, the substrate fixing device according to the present invention provides excellent thermal stability and electrostatic chucking performance by stably bonding the polyimide electrostatic chuck, the base member, and the ceramic plate. By utilizing the excellent insulation and thermal properties of the polyimide electrostatic chuck, precise fixing of the substrate is enabled even in high-temperature and vacuum environments, and process accuracy can be maximized by improving the positional precision of the substrate through the high flatness of the ceramic plate. Furthermore, by optimizing the thermal conductivity characteristics of the base member, uniformity of temperature distribution is ensured, and deformation caused by thermal stress during wafer heating and cooling is prevented.

[0199] Furthermore, based on its lightweight structure and excellent chemical resistance, the present invention provides a high-precision and high-reliability substrate handling solution required in semiconductor and display manufacturing processes. It enables stable wafer fixation under various process conditions, enhances ease of maintenance, and prevents contamination at the nanometer level, thereby contributing to the improvement of yield in advanced manufacturing processes.

[0200] As illustrated in FIG. 11, the large-area bonded substrate fixing device (800) according to an embodiment of the present invention may have a bonding layer (240) provided not only in the groove (124) but also on the upper side of the ceramic plate (121) which is outside the groove (124). That is, the bonding layer (240) may be provided not only in the groove (124) corresponding to the boundary area between the ceramic plates (121) but also on the entire upper side of the ceramic plate (121), and the upper side of the bonding layer (140) has a flatness of approximately 1 μm to approximately 30 μm.

[0201] As illustrated in FIG. 12, a large-area bonded substrate fixing device (900) according to an embodiment of the present invention may be similar to the large-area bonded substrate fixing device (100) illustrated in FIG. 2, except that the ceramic plate (121) and electrode layer (122) constituting the electrostatic chuck (920) are covered with a coating layer (923) rather than a bonding layer (130). Accordingly, the differences are mainly described.

[0202] The electrostatic chuck (920) may further include a ceramic coating layer (923) covering the ceramic plate (121) and the electrode layer (122). Accordingly, the bonding layer (130) can bond the ceramic coating layer (923) onto the base member (110).

[0203] The ceramic coating layer (923) can be provided in various ways. The ceramic coating layer (923) can be formed on the ceramic plate (121) and the electrode layer (122) by atmospheric pressure plasma spray, aerosol deposition, high-speed oxygen fuel spray, cold spray, or flame spray.

[0204] Atmospheric pressure plasma spraying is a method that uses high-temperature plasma to melt and accelerate ceramic materials for deposition on a surface, providing high adhesion and a uniform coating layer. This method is primarily used in environments requiring high-temperature resistance and enables the formation of thick coatings with excellent mechanical strength.

[0205] Aerosol deposition is a method of attaching ultrafine powder to a substrate by spraying it at high speed, enabling the formation of a coating layer with excellent adhesion even at relatively low temperatures. This method is advantageous for forming coating layers with high density and microstructure, and is applicable even to brittle materials such as ceramics.

[0206] High-speed oxygen-fuel spraying is a method of injecting coating particles at high speeds through the combustion of fuel and oxygen, capable of forming a dense coating layer with very high adhesive strength. This method is particularly useful in environments requiring wear resistance and corrosion resistance.

[0207] Cold spraying is a method that uses a supersonic airflow to collide powder particles with a substrate without heating, providing high adhesion while minimizing thermal effects. This method is applicable to heat-sensitive materials and can form a coating layer free from cracking and oxidation.

[0208] Flame spraying is a method that uses a flame generated by burning fuel gas to melt and spray coating materials, and it is a relatively simple and cost-effective method. However, the adhesion and uniformity of the coating may be somewhat lower compared to other high-temperature spraying methods.

[0209] By applying such various coating technologies, the present invention can form a uniform coating layer (923) with excellent adhesion on the ceramic plate and electrode layer, thereby improving the structural stability and durability of the substrate fixing device.

[0210] As illustrated in FIG. 13, a large-area bonded substrate fixing device (1000) according to an embodiment of the present invention may be similar to the large-area bonded substrate fixing device (1000) illustrated in FIG. 12, except that the coating layer (923), rather than the ceramic plate (121), faces upward (e.g., the area where the substrate is adsorbed). Accordingly, the differences are mainly described.

[0211] The electrostatic chuck (920) includes a ceramic coating layer (923) covering a ceramic plate (121) and an electrode layer (122), and the bonding layer (130) can bond the ceramic plate (121) onto a base member (110).

[0212] Accordingly, the groove (124) can be provided along the perimeter of the ceramic coating layer (923) rather than the ceramic plate (121). Additionally, by filling the groove (124) with a bonding layer (140), a plurality of electrostatic chucks (920) can be bonded to each other in a horizontal direction.

[0213] In one or more embodiments, the flatness of the electrostatic chuck (920) can be improved by grinding the ceramic coating layer (923) and the bonding layer (140) together.

[0214] In this way, by providing the ceramic coating layer (923) in a direction toward the substrate, various characteristics of the ceramic coating layer (923) (e.g., high resistance, high dielectric constant, or low resistance) can be controlled by the coating method, and accordingly, the characteristics of the substrate fixing device can be easily adjusted.

[0215] As illustrated in FIG. 14, a large-area bonded substrate fixing device (1100) according to an embodiment of the present invention may be similar to the substrate fixing device (500) illustrated in FIG. 8 and / or the substrate fixing device (700) illustrated in FIG. 10, except that the base member (110) has a side protrusion (1115) that protrudes upward along the periphery and is coupled to a ceramic plate (121) to protect an inner polyimide electrostatic chuck (530). Accordingly, the differences are mainly described.

[0216] In one or more embodiments, the side protrusion (1115) protrudes upward from the perimeter of the base member (110) by a thickness corresponding to the thickness of the polyimide electrostatic chuck (530), which may be bonded or joined to the ceramic plate (121). The side protrusion (1115) may generally wrap around the entire perimeter of the polyimide electrostatic chuck (530). That is, the side protrusion (1115) wraps around the sides of the polyimide insulating layer (531) bonded to the base member (110) and the bonding layer (540) bonded to the ceramic plate. Accordingly, process gases during the semiconductor or display manufacturing process cannot directly affect the polyimide electrostatic chuck (530), thereby extending the lifespan of the substrate fixing device (1100). These embodiments may be applied in the same or similar manner as the embodiments described in relation to FIGS. 2, FIGS. 5, FIGS. 8 through 13.

[0217] As illustrated in FIG. 15, a large-area bonded substrate fixing device (1200) according to an embodiment of the present invention may be similar to the substrate fixing device (1100) illustrated in FIG. 14, except that a side protrusion (1215) protrudes from the circumference of a ceramic plate (150) and is coupled to a base member (110) to protect an inner polyimide electrostatic chuck (530).

[0218] In one or more embodiments, the side protrusion (1215) protrudes downward from the perimeter of the ceramic plate (121) by a thickness corresponding to the thickness of the polyimide electrostatic chuck (530), which may be joined or bonded to the base member (110). The side protrusion (1215) may generally wrap around the entire perimeter of the polyimide electrostatic chuck (530). That is, the side protrusion (1215) wraps around the sides of the polyimide insulating layer (531) bonded to the base member (110) and the bonding layer (540) bonded to the ceramic plate (121). Accordingly, process gases during the semiconductor or display manufacturing process cannot directly affect the polyimide electrostatic chuck (530), thereby extending the lifespan of the substrate fixing device (1200). These embodiments may be applied in the same or similar manner as the embodiments described in relation to FIGS. 1 and FIGS. 4.

[0219] In this way, the present invention provides a technology that overcomes the manufacturing limitations of conventional single large ceramic electrostatic chucks through a large-area bonded substrate fixing device and enables stable substrate fixing even in high-temperature and high-vacuum environments. This allows for the maintenance of uniform process quality in semiconductor and display manufacturing processes and enables high-precision processes by preventing minute deformation of the substrate.

[0220] Furthermore, the present invention enables the stable support of large substrates by implementing an enlarged substrate fixing device through the bonding of multiple electrostatic chucks onto a single base member. This resolves the high cost associated with manufacturing conventional single large ceramic electrostatic chucks and provides cost savings by facilitating the replacement and maintenance of individual chucks through a modular structure. Additionally, long-term reliability is guaranteed by securing high mechanical strength and durability through the utilization of a multi-layer structure and optimized bonding and bonding layers.

[0221] In particular, the present invention is designed to maintain high flatness while securing uniform electrostatic chucking force by optimizing the bonding layer between electrostatic chucks. As a result, it can meet high-precision process requirements in semiconductor and display manufacturing processes and precisely fix various workpieces, such as wafers, glass substrates, and film substrates. Furthermore, through the optimized material design of the bonding and bonding layers, it provides a substrate fixing device with high heat resistance, vacuum resistance, and chemical resistance, thereby maintaining stable performance even in high-temperature and high-vacuum processes such as plasma etching and thin film deposition.

[0222] In addition, in order to improve the thermal management performance of the substrate fixing device, the present invention arranges heating and cooling lines inside the base member, thereby minimizing thermal stress generated during the process and maintaining temperature uniformity. Through this, thermal deformation of large substrates such as wafers and display panels can be prevented, and the precision of the process can be improved.

[0223] Another important technical effect of the present invention is the application of an anti-outgassing coating layer to improve reliability in a vacuum environment. By forming a plasma-resistant coating, such as yttrium oxide (Y2O3), on the portion of the bonding layer exposed to the external environment, gas emissions that may occur in the bonding layer can be minimized, and contamination in a vacuum environment can be prevented. This further enhances stability in semiconductor and display manufacturing processes that require high cleanliness.

[0224] In addition, the present invention provides lateral protrusions along the perimeter of the base member and / or ceramic plate. Accordingly, since the polyimide electrostatic chuck is not directly exposed to the process gas of the process chamber, gas emissions that may occur in the polyimide electrostatic chuck can be minimized, thereby preventing contamination of the vacuum environment.

[0225] Furthermore, the present invention ensures flexibility in the manufacturing process by applying a multilayer structure and provides the effect of reducing maintenance costs by designing it to enable partial replacement of damaged individual electrostatic chucks. In particular, in the embodiment applying a polyimide electrostatic chuck, the substrate can be stably fixed even in high-temperature environments by utilizing the excellent insulation and heat resistance of the polyimide insulating layer, and the substrate can be kept stable without shaking during the acceleration and deceleration of the equipment due to the lightweight structure.

[0226] Consequently, the present invention can contribute to improving productivity and yield in semiconductor and display manufacturing processes by implementing a substrate fixing device that provides high flatness and uniform electrostatic chucking force while stably maintaining large substrates. Furthermore, by ensuring high durability and long-term reliability through the design of optimized bonding and bonding layers, it is possible to reduce maintenance costs and maximize process stability.

[0227] Finally, although the present invention has mainly described a configuration in which a plurality of modularized electrostatic chucks are arranged in a matrix form and attached to a single base member, the aforementioned modularized electrostatic chucks may, in some cases, be provided as individual pieces attached to a base member. That is, by attaching a single electrostatic chuck to a single base member, it may be used as a substrate fixing device for adsorbing a small substrate.

[0228] The above description is merely one embodiment for implementing the large-area bonded substrate fixing device and the method for manufacturing the same according to the present invention. The present invention is not limited to the above-described embodiment, and the technical spirit of the present invention extends to the scope in which various modifications can be made by anyone with ordinary knowledge in the field to which the invention belongs, without departing from the gist of the invention as claimed in the following patent claims.

Claims

1. Base member; A plurality of electrostatic chucks provided on the base member and fixed to the substrate by electrostatic force; and It includes a plurality of bonding layers that mutually bond the base member and the plurality of electrostatic chucks, and The plurality of electrostatic chucks are provided with grooves along their circumference, and a bonding layer is filled into the grooves to bond the plurality of electrostatic chucks to one another. A substrate fixing device wherein each of the above plurality of electrostatic chucks comprises a ceramic plate and an electrode layer provided on the ceramic plate, and the bonding layer bonds the ceramic plate and the electrode layer onto the base member.

2. In Paragraph 1, A substrate fixing device wherein each of the above electrostatic chucks further comprises a coating layer covering the ceramic plate and the electrode layer, and the bonding layer bonds the coating layer onto the base member.

3. In Paragraph 2, A substrate fixing device in which the coating layer is formed on the ceramic plate and the electrode layer by means of atmospheric plasma spray, aerosol deposition, high velocity oxygen fuel (HVOF), cold spray, or flame spray.

4. In Paragraph 1, A substrate fixing device in which the bonding layer is provided over the entire upper surface of the ceramic plate outside the groove and the groove.

5. In Paragraph 1, A substrate fixing device further comprising a plurality of support members provided through the bonding layer between the upper side of the base member and the lower side of the ceramic plate.

6. In Paragraph 5, A substrate fixing device in which the plurality of support members extend from the base member toward the ceramic plate or extend from the ceramic plate toward the base member.

7. In Paragraph 5, A substrate fixing device in which the outermost support member among the plurality of support members mutually connects the base member and the outermost part of the ceramic plate so as not to expose the bonding layer to the outside.

8. In Paragraph 5, A substrate fixing device, wherein the bonding layer is filled and provided between the base member and the ceramic plate, which are spaced apart from each other by the plurality of support members.

9. Base missing; A plurality of lower bonding layers provided on the base member; A plurality of polyimide electrostatic chucks, each provided on the plurality of lower bonding layers above to fix a substrate by electrostatic force; A plurality of upper bonding layers, each provided on the plurality of polyimide electrostatic chucks; and It includes a plurality of ceramic plates, each provided on the plurality of upper bonding layers and on which the substrate is mounted. A substrate fixing device wherein the plurality of ceramic plates are provided with grooves along their circumference, and the grooves are filled with a bonding layer to bond the plurality of ceramic plates to each other.

10. In Paragraph 9, A substrate fixing device in which the bonding layer is provided over the entire upper surface of the ceramic plate outside the groove and the groove.

11. In Paragraph 9, A substrate fixing device comprising a base member made of ceramic, aluminum, titanium, MMC (Metal Matrix Composite), or SUS (Steel Use Stainless).

12. In Paragraph 9, The above polyimide electrostatic chuck is a substrate fixing device comprising a polyimide insulating layer and an electrode layer provided on the polyimide insulating layer.

13. In Paragraph 12, A substrate fixing device wherein the above polyimide insulating layer has a thermal decomposition temperature of 450 ℃ to 600 ℃, a continuous use temperature of 250 ℃ to 400 ℃, a dielectric constant of 3.0 to 3.6 (based on 1 kHz), a dielectric breakdown strength of 200 kV / mm to 300 kV / mm, a coefficient of thermal expansion of 4 ppm / ℃ to 80 ppm / ℃, a hygroscopicity of 0.1% to 1%, and a tensile strength of 100 MPa to 200 MPa.

14. In Paragraph 12, A substrate fixing device having a thickness of 10 μm to 500 μm of the polyimide insulating layer.

15. Base member; A plurality of polyimide electrostatic chucks bonded to the base member and fixed to the substrate by electrostatic force; and It includes a plurality of ceramic plates, each bonded to the plurality of polyimide electrostatic chucks and having the substrate mounted thereon, A substrate fixing device wherein the plurality of ceramic plates are provided with grooves along their circumference, and the grooves are filled with a bonding layer to bond the plurality of ceramic plates to each other.

16. In Paragraph 15, The above polyimide electrostatic chuck comprises a first polyimide insulating layer, an electrode layer provided on the first polyimide insulating layer, and a second polyimide insulating layer covering the first polyimide insulating layer and the electrode layer, forming a substrate fixing device.

17. In Paragraph 15, A substrate fixing device comprising the base member, the polyimide electrostatic chuck, and the ceramic plate, wherein the surface of the base member, the polyimide electrostatic chuck, and the ceramic plate are activated through plasma treatment, and then the polyimide electrostatic chuck is interposed between the base member and the ceramic plate and subsequently heat-pressurized to be joined to each other.

18. In Paragraph 17, A substrate fixing device in which a primer comprising a silane coupling agent, a titanium or aluminum-based compound is coated on the surface of the polyimide electrostatic chuck, and then the polyimide electrostatic chuck is interposed between the base member and the ceramic plate and subsequently heat-pressed to bond them together.

19. In Paragraph 17, A substrate fixing device comprising the base member, the polyimide electrostatic chuck, and the ceramic plate, wherein a sandblasting layer is formed on the surface, the polyimide electrostatic chuck is interposed between the base member and the ceramic plate, and then heat-pressurized to bond them together.

20. In Paragraph 17, A substrate fixing device in which the base member, the polyimide electrostatic chuck, and the ceramic plate are joined together by heat pressing while a temperature higher than the glass transition temperature of the polyimide electrostatic chuck is provided.

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