Transparent aluminum oxide multi-temperature-zone built-in heating electrostatic chuck and preparation method thereof

Abstract

The application discloses a transparent alumina multi-temperature-zone built-in heating electrostatic chuck and a preparation method thereof. The electrostatic chuck comprises a metal base, a bonding layer and a ceramic body. The bonding layer is attached to the upper surface of the metal base. The ceramic body is attached to the upper surface of the bonding layer. The ceramic body comprises at least one ceramic dielectric layer. The ceramic dielectric layer is an alumina ceramic which comprises the following raw materials by weight: 99.9-99.99 parts of alumina powder, 0.01-0.15 parts of sintering aid, 45-55 parts of solvent, 0.5-2.5 parts of dispersant, 7-11 parts of binder and 4-8 parts of plasticizer. The purity of the alumina powder of the alumina ceramic is 4N or more. The particle size of the alumina powder is 150-300 nm. The alumina ceramic is a high-purity alumina ceramic with a purity of 99.9% or more, a breakdown strength of >40 kV / mm, a dielectric constant of 9.5-10 and a bending strength of >450 MPa. The ceramic material used in the application has high purity and high ceramic density, which is beneficial to ensuring the safety of the electrostatic chuck under extreme environments.

Description

Technical Field

[0001] This invention relates to the field of semiconductor materials, and in particular to a transparent alumina multi-temperature zone built-in heating electrostatic chuck and its preparation method. Background Technology

[0002] Against the backdrop of rapid iteration in advanced semiconductor manufacturing processes, 3D memory chips are gradually developing towards ultra-large aperture depths and high aspect ratios, while logic chips continue to break through the limits of nanoscale small feature processes. Core processes such as wafer etching and deposition place higher demands on the RF carrying capacity, temperature control uniformity, structural stability, and lifespan of electrostatic chucks. As a core component of semiconductor process equipment, the material properties and temperature control structure of electrostatic chucks directly determine the consistency, precision, and mass production yield of wafer processing. Existing electrostatic chucks are no longer functionally compatible with the processing and production needs of advanced chips, severely restricting the process upgrades and large-scale mass production of high-end semiconductor chips.

[0003] Most existing electrostatic chucks use ordinary purity alumina or aluminum nitride ceramics as the substrate, which is difficult to adapt to the processing requirements of large-hole, small-feature chip under high RF power conditions; the specific manifestations are as follows: 1. In the high-RF power operating environment required by advanced processes, existing electrostatic chucks are prone to problems such as dielectric layer breakdown and arc discharge, which can damage the electrostatic chuck and cause wafer scrap.

[0004] 2. Conventional ceramic materials have a low dielectric constant, resulting in a small coupling capacitance between the wafer and the electrostatic chuck. This leads to poor radio frequency energy coupling efficiency and a large amount of radio frequency energy being wasted ineffectively within the chuck body. Consequently, the plasma sheath energy within the process cavity is insufficient, directly causing insufficient verticality of the deep etching of large holes in 3D memory chips and a large deviation in hole depth uniformity, making it difficult to meet the precision requirements of high aspect ratio deep hole machining.

[0005] 3. Conventional ceramics have high dielectric loss, which can cause severe local heat loss under high-frequency operating conditions, leading to local overheating and thermal warping of the wafer. For the processing of nanoscale small feature chips, it is very easy to cause defects such as pattern distortion and dimensional deviation, which significantly reduces the chip processing yield.

[0006] 4. Conventional ceramics have poor resistance to plasma erosion. Under long-term fluorine-based and chlorine-based plasma etching environment, the chuck surface will be continuously eroded, resulting in deterioration of surface roughness, uneven distribution of wafer adsorption force, low thermal conductivity of the material, poor heat conduction efficiency, and difficulty in ensuring the overall temperature uniformity of the wafer. This further aggravates the process consistency error in deep hole etching and small feature fabrication during the processing of large-size wafers.

[0007] Meanwhile, existing electrostatic chucks generally employ a single-temperature zone overall temperature control structure, which can only achieve a uniform temperature setting and lacks the ability to independently control and dynamically adjust temperature zones. During semiconductor deep-hole etching processes, the continuous action of plasma causes the wafer to generate self-heating, resulting in significant local temperature differences between the wafer's center and edges. The single-temperature zone structure cannot provide targeted cooling and power regulation for high-temperature areas, nor can it compensate for local thermal fluctuations during the process. This structure suffers from low temperature control accuracy, high thermal inertia, and slow dynamic response, making it difficult to meet the high-precision temperature control standards required for advanced chip manufacturing processes. Summary of the Invention

[0008] In view of this, the present invention addresses the deficiencies of the existing technology, and its main objective is to provide a transparent alumina multi-temperature zone built-in heating electrostatic chuck and its preparation method, which can effectively solve the problem that electrostatic chucks cannot be adapted to the small feature processing of advanced process logic chips and the high aspect ratio deep hole processing of 3D memory chips.

[0009] To achieve the above objectives, the present invention adopts the following technical solution: A transparent alumina multi-temperature zone built-in heating electrostatic chuck includes a metal base, an adhesive layer, and a ceramic body. The adhesive layer is attached to the upper surface of the metal base. The ceramic body is attached to the upper surface of the adhesive layer and includes at least one ceramic dielectric layer. The ceramic dielectric layer is alumina ceramic, which includes the following raw materials in parts by weight: 99.9-99.99 parts of alumina powder, 0.01-0.15 parts of sintering aid, 45-55 parts of solvent, 0.5-2.5 parts of dispersant, 7-11 parts of binder, and 4-8 parts of plasticizer. The purity of the alumina powder is above 4N, and the particle size of the alumina powder is 150-300 nm.

[0010] As a preferred embodiment, the ceramic body includes a first ceramic dielectric layer, an adsorption electrode layer, a second ceramic dielectric layer, a first heating electrode layer, a third ceramic dielectric layer, a second heating electrode layer, and a fourth ceramic dielectric layer arranged sequentially from top to bottom; the upper surface of the first ceramic dielectric layer is provided with a plurality of upwardly protruding protrusions; the fourth ceramic dielectric layer is disposed on the upper surface of the metal base through an adhesive layer.

[0011] As a preferred embodiment, the heating electrode layer adopts a double-layer partitioned conductive metal circuit. The first heating electrode layer is divided into 2-5 main heating zones from the inside out. The circuits in each zone are evenly wired in a spiral, planar serpentine, or planar loop shape, and are heated by high-power AC. The second heating electrode layer is divided into 2-5 compensation heating ring zones from the inside out. Each compensation heating ring zone is further divided into 40-200 sector zones according to requirements. The circuits in each sector are evenly wired in a spiral, planar serpentine, or planar loop shape, and are heated by low-power DC. The circuits in each zone are mutually insulated and independently powered.

[0012] As a preferred embodiment, the electrostatic chuck is also provided with multiple helium gas holes, which penetrate the lower and upper surfaces of the ceramic body from bottom to top.

[0013] A method for preparing a transparent alumina multi-temperature zone built-in heating electrostatic chuck, wherein the method for preparing the ceramic body includes the following steps: (1) Sand milling: According to the raw material composition of the ceramic dielectric layer, take 99.9-99.99 parts of alumina powder, 0.01-0.15 parts of sintering aid, 45-55 parts of solvent and 0.5-2.5 parts of dispersant and put them into the sand mill. Wet ultrafine grinding is carried out at the set speed and time to refine the particle size. After grinding, the material is discharged and filtered to remove coarse particles and impurities to obtain a uniform sand mill slurry. (2) Ball milling: Transfer the sand-milled slurry into a ball milling jar, add 7-11 parts of binder and 4-8 parts of plasticizer, and continue ball milling; then degas the ball-milled slurry to obtain cast slurry; (3) Casting and cutting: The degassed casting slurry is formed using a casting machine to obtain a ceramic green porcelain belt, which is then cut into multiple ceramic green porcelain pieces; (4) Drilling and printing filling: Structural holes and positioning holes are processed on the ceramic raw ceramic sheet; metal paste is printed and filled on the surface of the drilled ceramic raw ceramic sheet using a printing filling machine; (5) Stacking and vacuuming: Stack the printed ceramic raw ceramic pieces and then seal them in plastic; (6) Isostatic pressing: Pressing the plastic-sealed stacked sheets to obtain ceramic green porcelain plates; (7) Debinding: Place the ceramic raw porcelain plate on the corundum mullite firing plate, put it into the debinding furnace, and slowly heat it to 400-500℃ at a heating rate of 0.3-1℃ / min under nitrogen atmosphere, and keep it at the temperature for 3-6 hours to obtain the ceramic debinding sheet. (8) Sintering: The ceramic sheet is placed in a high-temperature sintering furnace and sintered at 1450-1550℃ for 2-4 hours in a hydrogen atmosphere to obtain the ceramic sintered sheet; (9) Machining: The sintered ceramic sheet is machined according to the drawings using machining equipment to obtain a ceramic body with a flatness of <5μm and a surface roughness of <0.1μm.

[0014] A method for preparing a transparent alumina multi-temperature zone built-in heating electrostatic chuck, wherein the method for preparing the ceramic body includes the following steps: (1) Sand milling: According to the raw material composition of the ceramic dielectric layer, take 99.9-99.99 parts of alumina powder, 0.01-0.15 parts of sintering aid, 45-55 parts of solvent and 0.5-2.5 parts of dispersant and put them into the sand mill. Wet ultrafine grinding is carried out at the set speed and time to refine the particle size. After grinding, the material is discharged and filtered to remove coarse particles and impurities to obtain a uniform sand mill slurry. (2) Ball milling: Transfer the sand mill slurry into a ball milling jar, add 7-11 parts of binder and 4-8 parts of plasticizer, and continue ball milling; then degas the ball-milled slurry to obtain the ball-milled slurry; (3) Granulation: The well-mixed ball mill slurry is granulated using a granulator to obtain granulated powder, which is then screened and batched using a vibrating screen; (4) Isostatic pressing: Pour the obtained granulated powder into a mold, place it in an isostatic press, and press it for 10-30 minutes at 60-80℃ and 180MPa to obtain a ceramic green porcelain plate. (5) Biscuit firing: Place the ceramic green porcelain plate into the sintering furnace, heat it to 900-1000℃ under nitrogen atmosphere, and hold it for 5-6 hours to obtain the ceramic green body; (6) CNC machining: Machining the shape, grooves and positioning structure of the ceramic blank according to the drawings, and controlling the machining allowance; (7) Printing: Using metal paste to print circuits, electrodes and functional layers on the surface of the CNC-machined blank; (8) Hot pressing sintering: The printed blank is placed in a hot pressing sintering furnace and sintered at 1450-1550℃ and 35MPa for 5-6 hours to obtain ceramic sintered parts; (9) Machining: The sintered ceramic sheet is machined according to the drawings using machining equipment to obtain a ceramic body with a flatness of <5μm and a surface roughness of <0.1μm.

[0015] A method for preparing a transparent alumina multi-temperature zone built-in heating electrostatic chuck, wherein the method for preparing the ceramic body includes the following steps: (1) Sand milling: According to the raw material composition of the ceramic dielectric layer, take 99.9-99.99 parts of alumina powder, 0.01-0.15 parts of sintering aid, 45-55 parts of solvent and 0.5-2.5 parts of dispersant and put them into the sand mill. Wet ultrafine grinding is carried out at the set speed and time to refine the particle size. After grinding, the material is discharged and filtered to remove coarse particles and impurities to obtain a uniform sand mill slurry. (2) Ball milling: Transfer the sand mill slurry into a ball milling jar, add 7-11 parts of binder and 4-8 parts of plasticizer, and continue ball milling; then degas the ball-milled slurry to obtain the ball-milled slurry; (3) Granulation: The well-mixed ball mill slurry is granulated using a granulator to obtain granulated powder, which is then screened and batched using a vibrating screen; (4) Isostatic pressing: Pour the obtained granulated powder into a mold, place it in an isostatic press, and press it for 10-30 minutes at 60-80℃ and 180MPa to obtain a ceramic green porcelain plate. (5) CNC machining: Roughly machine the shape, grooves and positioning structure of the ceramic blank according to the drawings, and control the machining allowance; (6) Carbon removal: The machined green blank is placed in a carbon removal furnace and heated slowly to 400-500℃ at a heating rate of 0.3-1℃ / min under a nitrogen atmosphere. The temperature is held for 3-6 hours to completely decompose the organic binder and other residues in the green blank and obtain ceramic carbon removal sheets. (7) First hot pressing sintering: The carbon-removed blank is placed in a hot pressing sintering furnace and sintered at 1400-1500℃ and 35MPa for 5-6 hours to obtain the initial fired ceramic parts; (8) CNC machining: Precision machining of the shape, grooves and positioning structure of the initial fired ceramic parts; (9) Printing: Using metal paste to print circuits, electrodes and functional layers on the surface of the finished blank; (10) Secondary hot pressing sintering: The printed blank is placed in a hot pressing sintering furnace and sintered at 1450-1550℃ and 35MPa for 5-6 hours to obtain ceramic sintered parts; (11) Machining: The sintered ceramic sheet is machined according to the drawings using machining equipment to obtain a ceramic body with a flatness of <5μm and a surface roughness of <0.1μm.

[0016] As a preferred embodiment, the sintering aid is at least one of MgO, magnesium aluminum spinel, and Mg(NO3)2; the solvent is ethanol; the dispersant is at least one of castor oil, fish oil, polyethylene glycol, and phosphate ester; the binder is polyvinyl butyral; and the plasticizer is at least one of dioctyl phthalate, dimethyl phthalate, dibutyl phthalate, and diisononyl phthalate.

[0017] As a preferred embodiment, the metal paste is at least one of platinum, ruthenium, and rhodium.

[0018] As a preferred embodiment, the ceramic body and the metal base are assembled using an adhesive layer to form an electrostatic chuck.

[0019] Compared with the prior art, the present invention has obvious advantages and beneficial effects. Specifically, as can be seen from the above technical solution: 1. This invention utilizes alumina powder with a purity of 4N or higher to prepare a high-purity transparent alumina ceramic electrostatic chuck, whose overall performance surpasses that of electrostatic chucks made from conventional alumina ceramics. This material exhibits high breakdown strength, making it suitable for high-frequency power operation and effectively preventing abnormalities such as high-voltage discharge and breakdown leakage, thus improving equipment operational stability. Its high dielectric constant effectively enhances RF coupling efficiency, increases RF energy utilization, and ensures stable process operation. Low dielectric loss significantly reduces energy loss under RF conditions, minimizing process parameter fluctuations and ensuring consistent wafer processing. Furthermore, this material possesses strong resistance to plasma corrosion, resisting long-term plasma impact and corrosion, effectively inhibiting chuck aging, cracking, and interlayer separation, extending equipment lifespan. In addition, high-purity transparent alumina has high thermal conductivity, resulting in uniform heat conduction and improving temperature uniformity across the chuck surface.

[0020] 2. This invention employs a multi-temperature zone independent temperature control scheme. Compared to conventional electrostatic chuck single-temperature zone overall temperature control, it offers the advantage of high temperature uniformity, effectively improving the consistency of the entire wafer etching process. During etching, the wafer is prone to localized self-heating due to plasma reactions, causing regional temperature differences, which in turn leads to uneven etching and low yield across the entire wafer. This invention enables independent temperature adjustment for each zone, allowing for precise cooling of high-temperature areas and temperature compensation of low-temperature areas, dynamically offsetting temperature deviations caused by process self-heating, and effectively improving the temperature uniformity of the entire wafer.

[0021] 3. This invention employs a built-in heating circuit, offering significant advantages over traditional structures such as external heating and surface-mount heating. The internal heating structure features a short heat conduction path, low heat loss, and rapid temperature response, quickly matching process parameter switching requirements and adapting to high-precision, high-frequency process control. Simultaneously, the internal heating structure exhibits strong stability, effectively avoiding problems such as plasma corrosion, mechanical vibration detachment, and high-temperature aging failure inherent in external heating components. It can operate stably even under long-term high-temperature, high-pressure, and plasma-exposed harsh conditions, resulting in a long service life and high operational reliability.

[0022] 4. The present invention provides three preparation processes for transparent alumina multi-temperature zone built-in heating electrostatic chucks, namely hydrogen sintering, hot pressing sintering, and secondary hot pressing sintering. Compared with the traditional air sintering process, the preparation method provided by the present invention is simple and has high process reliability; at the same time, the present invention uses tungsten electrodes instead of traditional palladium electrodes, which can significantly reduce production costs.

[0023] 5. This invention overcomes the technical bottleneck of conventional electrostatic chucks in meeting the etching requirements for small features and high aspect ratios through synergistic optimization of materials, structure, and fabrication methods. It can meet the precision etching requirements of small feature sizes in advanced logic chips, effectively improving issues such as linewidth deviation and edge defects in small-size processes. Simultaneously, it is adaptable to the etching conditions of large apertures and high aspect ratios in 3D memory chips, stably resolving process defects such as uneven aperture, rough hole walls, and residue at the bottom of holes during high-depth hole etching. It can be widely applied in advanced semiconductor manufacturing fields such as high-end logic chips and 3D memory chips.

[0024] To more clearly illustrate the structural features and effects of the present invention, the present invention will be described in detail below with reference to the accompanying drawings and specific embodiments. Attached Figure Description

[0025] Figure 1 This is an exploded view of the present invention; Figure 2 This is a schematic diagram of the first heating electrode layer in this invention; Figure 3 This is a schematic diagram of the second heating electrode layer in this invention.

[0026] Explanation of reference numerals in the attached diagram: 10. Metal base; 20. Ceramic body; 21. First ceramic dielectric layer; 211. Protrusion; 22. Adsorption electrode layer; 23. Second ceramic dielectric layer; 24. First heating electrode layer; 241. Main heating area; 25. Third ceramic dielectric layer; 26. Second heating electrode layer; 261. Compensation heating ring area; 27. Fourth ceramic dielectric layer; 201. Fan-shaped area; 202. Helium gas hole. Detailed Implementation

[0027] Please refer to Figures 1 to 2 As shown, it illustrates the specific structure of a transparent alumina multi-temperature zone built-in heating electrostatic chuck of the present invention, which includes a metal base 10, an adhesive layer (not shown in the figure), and a ceramic body 20.

[0028] The adhesive layer is bonded to the upper surface of the metal base; the ceramic body 20 is bonded to the upper surface of the adhesive layer, and the ceramic body 20 includes at least one ceramic dielectric layer; the ceramic dielectric layer is alumina ceramic, which includes the following raw materials in parts by weight: 99.9-99.99 parts of alumina powder, 0.01-0.15 parts of sintering aid, 45-55 parts of solvent, 0.5-2.5 parts of dispersant, 7-11 parts of binder and 4-8 parts of plasticizer, the alumina powder has a purity of 4N or higher, the alumina powder has a particle size of 150-300nm, and the alumina ceramic is a high-purity alumina ceramic with a purity of 99.9% or higher, a breakdown strength > 40kV / mm, a dielectric constant of 9.5-10, and a flexural strength > 450MPa. Specifically, the ceramic body 20 includes, from top to bottom, a first ceramic dielectric layer 21, an adsorption electrode layer 22, a second ceramic dielectric layer 23, a first heating electrode layer 24, a third ceramic dielectric layer 25, a second heating electrode layer 26, and a fourth ceramic dielectric layer 27. The upper surface of the first ceramic dielectric layer 21 is provided with multiple upwardly protruding protrusions 211. The heating electrode layer adopts a double-layer partitioned conductive metal circuit. Specifically, the first heating electrode layer 24 is divided into 2-5 main heating zones 241 from the inside out. The circuits in each zone are evenly wired in a spiral, planar serpentine, or planar loop shape, and are heated by high-power AC. The second heating electrode layer 26 is divided into 2-5 compensation heating ring zones 261 from the inside out. The compensation heating ring zones 261 are further divided into 40-200 fan-shaped zones 201 as needed. The circuits in each zone are evenly wired in a spiral, planar serpentine, or planar loop shape, and are heated by low-power DC. The circuits in each partition are mutually insulated and independently powered. The fourth ceramic dielectric layer 27 is disposed on the upper surface of the metal base via an adhesive layer. Furthermore, the electrostatic chuck is provided with a plurality of helium gas holes 202, which penetrate from bottom to top through the lower and upper surfaces of the ceramic body 20.

[0029] This invention also discloses a method for preparing a transparent alumina multi-temperature zone built-in heating electrostatic chuck, wherein the method for preparing the ceramic body 20 includes the following steps: (1) Sand milling: Based on the raw material composition of the ceramic dielectric layer, 99.9-99.95 parts of alumina powder, 0.01-0.15 parts of sintering aid, 45-55 parts of solvent, and 0.5-2.5 parts of dispersant are added to a sand mill and wet ultrafine grinding is performed at the set speed and time to refine the particle size. After grinding, the material is discharged, filtered to remove coarse particles and impurities, and a uniform sand milling slurry is obtained. The sintering aid is at least one of MgO, magnesium aluminum spinel, and Mg(NO3)2; the solvent is ethanol; and the dispersant is at least one of castor oil, tartaric acid oil, polyethylene glycol, and phosphate ester.

[0030] (2) Ball milling: Transfer the sand-milled slurry into a ball milling jar, add 7-11 parts of binder and 4-8 parts of plasticizer, and continue ball milling; then degas the ball-milled slurry to obtain a cast slurry; the binder is polyvinyl butyral; the plasticizer is at least one of dioctyl phthalate, dimethyl phthalate, dibutyl phthalate and diisononyl phthalate.

[0031] (3) Casting and cutting: The degassed casting slurry is formed using a casting machine to obtain a ceramic raw porcelain strip, which is then cut into multiple ceramic raw porcelain pieces.

[0032] (4) Drilling and printing filling: Structural holes and positioning holes are processed on the ceramic green ceramic sheet; a printing filling machine is used to print and fill the holes with metal paste on the surface of the drilled ceramic green ceramic sheet. The metal paste is at least one of platinum, ruthenium and rhodium, and alumina ceramic powder is added to the metal paste to ensure the bonding strength between the printed lines and the green body; at the same time, its resistance is further adjusted by adjusting the amount of metal paste added.

[0033] (5) Stacking and vacuuming: Stack the printed ceramic raw ceramic pieces and then seal them.

[0034] (6) Isostatic pressing: Press the plastic-sealed stacked sheets to obtain ceramic green porcelain plates.

[0035] (7) Debinding: Place the ceramic raw porcelain plate on the corundum mullite firing plate, put it into the debinding furnace, and slowly heat it to 400-500℃ at a heating rate of 0.3-1℃ / min under nitrogen atmosphere, and keep it at the temperature for 3-6 hours to obtain the ceramic debinding sheet.

[0036] (8) Sintering: The ceramic sheet is placed in a high-temperature sintering furnace and sintered at 1450-1550℃ for 2-4 hours in a hydrogen atmosphere to obtain the ceramic sintered sheet.

[0037] (9) Machining: The sintered ceramic sheet is machined according to the drawings using machining equipment to obtain a ceramic body 20 with a flatness of <5μm and a surface roughness of <0.1μm.

[0038] The ceramic body 20 and the metal base are assembled through an adhesive layer to form an electrostatic chuck.

[0039] This invention also discloses another method for preparing a transparent alumina multi-temperature zone built-in heating electrostatic chuck, wherein the method for preparing the ceramic body 20 includes the following steps: (1) Sand milling: According to the raw material composition of the ceramic dielectric layer, 99.9-99.99 parts of alumina powder, 0.01-0.15 parts of sintering aid, 45-55 parts of solvent and 0.5-2.5 parts of dispersant are put into a sand mill and wet ultrafine grinding is carried out at the set speed and time to refine the particle size; after grinding, the material is discharged and filtered to remove coarse particles and impurities to obtain a uniform sand milling slurry; the sintering aid is at least one of MgO, magnesium aluminum spinel and Mg(NO3)2; the solvent is ethanol; the dispersant is at least one of castor oil, tartaric acid oil, polyethylene glycol and phosphate ester.

[0040] (2) Ball milling: Transfer the sand mill slurry into a ball milling jar, add 7-11 parts of binder and 4-8 parts of plasticizer, and continue ball milling; then degas the ball-milled slurry to obtain ball milled slurry; the binder is polyvinyl butyral; the plasticizer is at least one of dioctyl phthalate, dimethyl phthalate, dibutyl phthalate and diisononyl phthalate.

[0041] (3) Granulation: The well-mixed ball mill slurry is granulated using a granulator to obtain granulated powder, which is then screened and batched using a vibrating screen.

[0042] (4) Isostatic pressing: Pour the obtained granulated powder into a mold, place it in an isostatic press, and press it for 10-30 minutes at 60-80℃ and 180MPa to obtain a ceramic green porcelain plate.

[0043] (5) Biscuit firing: Place the ceramic green porcelain plate into the sintering furnace, heat it to 900-1000℃ under nitrogen atmosphere, and hold it for 5-6 hours to obtain the ceramic green body.

[0044] (6) CNC machining: Machining the ceramic blank shape, grooves and positioning structure according to the drawings, and controlling the machining allowance.

[0045] (7) Printing: The circuits, electrodes and functional layers are printed on the surface of the CNC-machined blank using metal paste. The metal paste is at least one of platinum, ruthenium and rhodium, and alumina ceramic powder is added to ensure the bonding strength between the printed circuit and the blank; at the same time, its resistance is further adjusted by adjusting the amount of metal paste added.

[0046] (8) Hot pressing sintering: The printed blank is placed in a hot pressing sintering furnace and sintered at 1450-1550℃ and 35MPa for 5-6 hours to obtain ceramic sintered parts.

[0047] (9) Machining: The sintered ceramic sheet is machined according to the drawings using machining equipment to obtain a ceramic body 20 with a flatness of <5μm and a surface roughness of <0.1μm.

[0048] The ceramic body 20 and the metal base are assembled through an adhesive layer to form an electrostatic chuck.

[0049] This invention also discloses a method for preparing a transparent alumina multi-temperature zone built-in heating electrostatic chuck, wherein the method for preparing the ceramic body 20 includes the following steps: (1) Sand milling: According to the raw material composition of the ceramic dielectric layer, 99.9-99.99 parts of alumina powder, 0.01-0.15 parts of sintering aid, 45-55 parts of solvent and 0.5-2.5 parts of dispersant are put into a sand mill and wet ultrafine grinding is carried out at the set speed and time to refine the particle size; after grinding, the material is discharged and filtered to remove coarse particles and impurities to obtain a uniform sand milling slurry; the sintering aid is at least one of MgO, magnesium aluminum spinel and Mg(NO3)2; the solvent is ethanol; the dispersant is at least one of castor oil, tartaric acid oil, polyethylene glycol and phosphate ester.

[0050] (2) Ball milling: Transfer the sand mill slurry into a ball milling jar, add 7-11 parts of binder and 4-8 parts of plasticizer, and continue ball milling; then degas the ball-milled slurry to obtain ball milled slurry; the binder is polyvinyl butyral; the plasticizer is at least one of dioctyl phthalate, dimethyl phthalate, dibutyl phthalate and diisononyl phthalate.

[0051] (3) Granulation: The well-mixed ball mill slurry is granulated using a granulator to obtain granulated powder, which is then screened and batched using a vibrating screen.

[0052] (4) Isostatic pressing: Pour the obtained granulated powder into a mold, place it in an isostatic press, and press it for 10-30 minutes at 60-80℃ and 180MPa to obtain a ceramic green porcelain plate.

[0053] (5) CNC machining: Roughly machine the shape, grooves and positioning structure of the ceramic blank according to the drawings, and control the machining allowance.

[0054] (6) Carbon removal: The machined green blank is placed in a carbon removal furnace and heated slowly to 400-500℃ at a heating rate of 0.3-1℃ / min under a nitrogen atmosphere. The temperature is held for 3-6 hours to completely decompose the organic binder and other residues in the green blank, and obtain ceramic carbon removal sheets.

[0055] (7) First hot pressing sintering: The carbon-removed blank is placed in a hot pressing sintering furnace and sintered at 1400-1500℃ and 35MPa for 5-6 hours to obtain the initial fired ceramic parts.

[0056] (8) CNC machining: to perform precision machining on the shape, grooves and positioning structure of the initial fired ceramic parts.

[0057] (9) Printing: The circuits, electrodes and functional layers are printed on the surface of the finished blank using a metal paste. The metal paste is at least one of platinum, palladium, ruthenium and rhodium, and alumina ceramic powder is added to the metal paste to ensure the bonding strength between the printed circuits and the blank; at the same time, its resistance is further adjusted by adjusting the amount of metal paste added.

[0058] (10) Secondary hot pressing sintering: The printed blank is placed in a hot pressing sintering furnace and sintered at 1450-1550℃ and 35MPa for 5-6 hours to obtain ceramic sintered parts.

[0059] (11) Machining: The sintered ceramic sheet is machined according to the drawings using machining equipment to obtain a ceramic body 20 with a flatness of <5μm and a surface roughness of <0.1μm.

[0060] The ceramic body 20 and the metal base are assembled through an adhesive layer to form an electrostatic chuck.

[0061] The following detailed description uses several embodiments and comparative examples: Example 1: A transparent alumina multi-temperature zone built-in heating electrostatic chuck includes a metal base 10, an adhesive layer (not shown in the figure), and a ceramic body 20.

[0062] The adhesive layer is bonded to the upper surface of the metal base; the ceramic body 20 is bonded to the upper surface of the adhesive layer, and the ceramic body 20 includes at least one ceramic dielectric layer; the ceramic dielectric layer is alumina ceramic, which includes the following raw materials in parts by weight: 99.9 parts of alumina powder, 0.01 parts of sintering aid, 45 parts of solvent, 0.5 parts of dispersant, 7 parts of binder and 4 parts of plasticizer, the purity of the alumina powder is above 4N, and the particle size of the alumina powder is 150nm. Specifically, the ceramic body 20 includes, from top to bottom, a first ceramic dielectric layer 21, an adsorption electrode layer 22, a second ceramic dielectric layer 23, a first heating electrode layer 24, a third ceramic dielectric layer 25, a second heating electrode layer 26, and a fourth ceramic dielectric layer 27. The upper surface of the first ceramic dielectric layer 21 has multiple upwardly protruding protrusions 211. The heating electrode layer employs a double-layer partitioned conductive metal circuit. Specifically, the first heating electrode layer 24 is divided into 2-5 main heating zones 241 from the inside out, with each zone's circuitry arranged in a spiral, planar serpentine, or planar loop shape for uniform wiring, and uses high-power AC heating. The second heating electrode layer 26 is divided into 2-5 compensation heating ring zones 261 from the inside out, and each compensation heating ring zone 261 is further divided into 40-200 fan-shaped zones 201 as needed, with each zone's circuitry arranged in a spiral, planar serpentine, or planar loop shape for uniform wiring, and uses low-power DC heating. The circuitry in each partition is mutually insulated and independently powered. The fourth ceramic dielectric layer 27 is disposed on the upper surface of the metal base via an adhesive layer. Furthermore, the electrostatic chuck is provided with a plurality of helium gas holes 202, which penetrate from bottom to top through the lower and upper surfaces of the ceramic body 20.

[0063] This embodiment discloses a method for preparing a transparent alumina multi-temperature zone built-in heating electrostatic chuck. The method for preparing the ceramic body 20 includes the following steps: (1) Sand milling: Based on the raw material composition of the ceramic dielectric layer, 99.9 parts of alumina powder, 0.01 parts of sintering aid, 45 parts of solvent and 0.5 parts of dispersant were added to a sand mill and wet ultrafine grinding was carried out at the set speed and time to refine the particle size; after grinding, the material was discharged, filtered to remove coarse particles and impurities, and a uniform sand milling slurry was obtained. The sintering aid is MgO; the solvent is ethanol; and the dispersant is castor oil.

[0064] (2) Ball milling: Transfer the sand mill slurry into a ball milling jar, add 7 parts of binder and 4 parts of plasticizer, and continue ball milling; then degas the ball-milled slurry to obtain a cast slurry; the binder is polyvinyl butyral; the plasticizer is dioctyl phthalate.

[0065] (3) Casting and cutting: The degassed casting slurry is formed using a casting machine to obtain a ceramic raw porcelain strip, which is then cut into multiple ceramic raw porcelain pieces.

[0066] (4) Drilling and printing filling: Structural holes and positioning holes are processed on the ceramic green ceramic sheet; a printing filling machine is used to print and fill the holes with metal paste on the surface of the drilled ceramic green ceramic sheet. The metal paste is platinum and palladium, and alumina ceramic powder is added to the metal paste to ensure the bonding strength between the printed lines and the green body; at the same time, the resistance is further adjusted by adjusting the amount of metal paste added.

[0067] (5) Stacking and vacuuming: Stack the printed ceramic raw ceramic pieces and then seal them in plastic; (6) Isostatic pressing: Press the plastic-sealed stacked sheets to obtain ceramic green porcelain plates.

[0068] (7) Debinding: Place the ceramic raw porcelain plate on the corundum mullite firing plate, put it into the debinding furnace, and slowly heat it to 400°C at a heating rate of 0.3°C / min under nitrogen atmosphere. Hold it at this temperature for 3 hours to obtain the ceramic debinding sheet.

[0069] (8) Sintering: The ceramic sheet is placed in a high-temperature sintering furnace and sintered at 1450°C for 2 hours under a hydrogen atmosphere to obtain the ceramic sintered sheet.

[0070] (9) Machining: The sintered ceramic sheet is machined according to the drawings using machining equipment to obtain a ceramic body 20 with a flatness of <5μm and a surface roughness of <0.1μm.

[0071] The ceramic body 20 and the metal base are assembled through an adhesive layer to form an electrostatic chuck.

[0072] Example 2: A transparent alumina multi-temperature zone built-in heating electrostatic chuck includes a metal base 10, an adhesive layer (not shown in the figure), and a ceramic body 20.

[0073] The adhesive layer is bonded to the upper surface of the metal base; the ceramic body 20 is bonded to the upper surface of the adhesive layer, and the ceramic body 20 includes at least one ceramic dielectric layer; the ceramic dielectric layer is alumina ceramic, which includes the following raw materials in parts by weight: 99.99 parts of alumina powder, 0.15 parts of sintering aid, 55 parts of solvent, 5 parts of dispersant, 11 parts of binder and 8 parts of plasticizer, the purity of the alumina powder is above 4N, and the particle size of the alumina powder is 300nm. Specifically, the ceramic body 20 includes, from top to bottom, a first ceramic dielectric layer 21, an adsorption electrode layer 22, a second ceramic dielectric layer 23, a first heating electrode layer 24, a third ceramic dielectric layer 25, a second heating electrode layer 26, and a fourth ceramic dielectric layer 27. The upper surface of the first ceramic dielectric layer 21 is provided with multiple upwardly protruding protrusions 211. The heating electrode layer adopts a double-layer partitioned conductive metal circuit. Specifically, the first heating electrode layer 24 is divided into 2-5 main heating zones 241 from the inside out. The circuits in each zone are evenly wired in a spiral, planar serpentine, or planar loop shape, and are heated by high-power AC. The second heating electrode layer 26 is divided into 2-5 compensation heating ring zones 261 from the inside out. The compensation heating ring zones 261 are further divided into 40-200 fan-shaped zones 201 as needed. The circuits in each zone are evenly wired in a spiral, planar serpentine, or planar loop shape, and are heated by low-power DC. The circuits in each partition are mutually insulated and independently powered. The fourth ceramic dielectric layer 27 is disposed on the upper surface of the metal base via an adhesive layer. Furthermore, the electrostatic chuck is provided with a plurality of helium gas holes 202, which penetrate from bottom to top through the lower and upper surfaces of the ceramic body 20.

[0074] This embodiment discloses a method for preparing a transparent alumina multi-temperature zone built-in heating electrostatic chuck. The method for preparing the ceramic body 20 includes the following steps: (1) Sand milling: According to the raw material composition of the ceramic dielectric layer, 99.95 parts of alumina powder, 0.15 parts of sintering aid, 55 parts of solvent and 2.5 parts of dispersant are put into a sand mill and wet ultrafine grinding is carried out at the set speed and time to refine the particle size; after grinding, the material is discharged, and the coarse particles and impurities are removed by filtration to obtain a uniform sand milling slurry; the sintering aid is magnesium aluminum spinel; the solvent is ethanol; the dispersant is tartar oil.

[0075] (2) Ball milling: Transfer the sand mill slurry into a ball milling jar, add 11 parts of binder and 8 parts of plasticizer, and continue ball milling; then degas the ball-milled slurry to obtain ball milled slurry; the binder is polyvinyl butyral; the plasticizer is dimethyl phthalate.

[0076] (3) Granulation: The well-mixed ball mill slurry is granulated using a granulator to obtain granulated powder, which is then screened and batched using a vibrating screen.

[0077] (4) Isostatic pressing: Pour the obtained granulated powder into a mold, place it in an isostatic press, and press it for 30 minutes at 80℃ and 180MPa to obtain a ceramic green porcelain plate.

[0078] (5) Biscuit firing: Place the ceramic green porcelain plate into the sintering furnace, heat it to 1000℃ under nitrogen atmosphere, and hold it for 6 hours to obtain the ceramic green body.

[0079] (6) CNC machining: Machining the ceramic blank shape, grooves and positioning structure according to the drawings, and controlling the machining allowance.

[0080] (7) Printing: The circuits, electrodes and functional layers are printed on the surface of the CNC-machined blank using metal paste. The metal paste is ruthenium, and alumina ceramic powder is added to ensure the bonding strength between the printed circuit and the blank; at the same time, the resistance is further adjusted by adjusting the amount of metal paste added.

[0081] (8) Hot pressing sintering: The printed blank is placed in a hot pressing sintering furnace and sintered at 1550℃ and 35MPa for 6 hours to obtain ceramic sintered parts.

[0082] (9) Machining: The sintered ceramic sheet is machined according to the drawings using machining equipment to obtain a ceramic body 20 with a flatness of <5μm and a surface roughness of <0.1μm.

[0083] The ceramic body 20 and the metal base are assembled through an adhesive layer to form an electrostatic chuck.

[0084] Example 3: A transparent alumina multi-temperature zone built-in heating electrostatic chuck includes a metal base 10, an adhesive layer (not shown in the figure), and a ceramic body 20.

[0085] The adhesive layer is bonded to the upper surface of the metal base; the ceramic body 20 is bonded to the upper surface of the adhesive layer, and the ceramic body 20 includes at least one ceramic dielectric layer; the ceramic dielectric layer includes the following raw materials in parts by weight: 99.99 parts of alumina powder, 0.11 parts of sintering aid, 50 parts of solvent, 1.8 parts of dispersant, 9 parts of binder and 6 parts of plasticizer, wherein the purity of the alumina powder is above 4N and the particle size of the alumina powder is 200nm. Specifically, the ceramic body 20 includes, from top to bottom, a first ceramic dielectric layer 21, an adsorption electrode layer 22, a second ceramic dielectric layer 23, a first heating electrode layer 24, a third ceramic dielectric layer 25, a second heating electrode layer 26, and a fourth ceramic dielectric layer 27. The upper surface of the first ceramic dielectric layer 21 is provided with multiple upwardly protruding protrusions 211. The heating electrode layer adopts a double-layer partitioned conductive metal circuit. Specifically, the first heating electrode layer 24 is divided into 2-5 main heating zones 241 from the inside out. The circuits in each zone are evenly wired in a spiral, planar serpentine, or planar loop shape, and are heated by high-power AC. The second heating electrode layer 26 is divided into 2-5 compensation heating ring zones 261 from the inside out. The compensation heating ring zones 261 are further divided into 40-200 fan-shaped zones 201 as needed. The circuits in each zone are evenly wired in a spiral, planar serpentine, or planar loop shape, and are heated by low-power DC. The circuits in each partition are mutually insulated and independently powered. The fourth ceramic dielectric layer 27 is disposed on the upper surface of the metal base via an adhesive layer. Furthermore, the electrostatic chuck is provided with a plurality of helium gas holes 202, which penetrate from bottom to top through the lower and upper surfaces of the ceramic body 20.

[0086] This embodiment discloses a method for preparing a transparent alumina multi-temperature zone built-in heating electrostatic chuck. The method for preparing the ceramic body 20 includes the following steps: (1) Sand milling: According to the raw material composition of the ceramic dielectric layer, 99.99 parts of alumina powder, 0.11 parts of sintering aid, 50 parts of solvent and 1.8 parts of dispersant are put into a sand mill and wet ultrafine grinding is carried out at the set speed and time to refine the particle size; after grinding, the material is discharged, filtered to remove coarse particles and impurities, and a uniform sand milling slurry is obtained; the sintering aid is a mixture of MgO, magnesium aluminum spinel and Mg(NO3)2; the solvent is ethanol; the dispersant is a mixture of castor oil, tartaric acid oil, polyethylene glycol and phosphate ester.

[0087] (2) Ball milling: Transfer the sand mill slurry into a ball milling jar, add 9 parts of binder and 6 parts of plasticizer, and continue ball milling; then degas the ball-milled slurry to obtain ball milled slurry; the binder is polyvinyl butyral; the plasticizer is a mixture of dioctyl phthalate, dimethyl phthalate, dibutyl phthalate and diisononyl phthalate.

[0088] (3) Granulation: The well-mixed ball mill slurry is granulated using a granulator to obtain granulated powder, which is then screened and batched using a vibrating screen.

[0089] (4) Isostatic pressing: Pour the obtained granulated powder into a mold, place it in an isostatic press, and press it for 20 minutes at 70℃ and 180MPa to obtain a ceramic green porcelain plate.

[0090] (5) CNC machining: Roughly machine the shape, grooves and positioning structure of the ceramic blank according to the drawings, and control the machining allowance.

[0091] (6) Carbon removal: The machined green blank is placed in a carbon removal furnace and heated slowly to 450°C at a heating rate of 0.6°C / min under a nitrogen atmosphere. The temperature is held for 4 hours to completely decompose the organic binder and other residues in the green blank, and ceramic carbon removal sheet is obtained.

[0092] (7) First hot pressing sintering: The carbon-removed blank is placed in a hot pressing sintering furnace and sintered at 1450℃ and 35MPa for 5.5 hours to obtain the initial fired ceramic parts.

[0093] (8) CNC machining: to perform precision machining on the shape, grooves and positioning structure of the initial fired ceramic parts.

[0094] (9) Printing: The circuits, electrodes and functional layers are printed on the surface of the finished blank using a metal paste. The metal paste is a mixture of platinum, ruthenium and rhodium, and alumina ceramic powder is added to ensure the bonding strength between the printed circuit and the blank; at the same time, the resistance is further adjusted by adjusting the amount of metal paste added.

[0095] (10) Secondary hot pressing sintering: The printed blank is placed in a hot pressing sintering furnace and sintered at 1500℃ and 35MPa for 5.5 hours to obtain ceramic sintered parts.

[0096] (11) Machining: The sintered ceramic sheet is machined according to the drawings using machining equipment to obtain a ceramic body 20 with a flatness of <5μm and a surface roughness of <0.1μm.

[0097] The ceramic body 20 and the metal base are assembled through an adhesive layer to form an electrostatic chuck.

[0098] Comparative example: The conventional preparation method for the high-purity transparent alumina ceramic electrostatic chuck used in this comparative example employs palladium electrodes, which are costly. The preparation process involves air sintering and HIP sintering, which is complex and results in low product yield. Furthermore, it cannot incorporate heating circuitry. Therefore, the electrostatic chuck prepared by this method exhibits inferior temperature uniformity, temperature control progress, and response time compared to the electrostatic chucks prepared by the methods described in the various embodiments.

[0099] Its performance indicators are as follows:

[0100] As shown in the table above, the preparation method of the transparent alumina multi-temperature zone built-in heating electrostatic chuck provided in Examples 1-3 of this invention utilizes high-purity alumina powder, resulting in high material breakdown strength, excellent dielectric properties, thermal conductivity, and resistance to plasma erosion. Through independent temperature control design for multiple temperature zones, local temperature differences can be dynamically compensated, significantly improving the temperature uniformity of the chuck surface and increasing processing yield. Furthermore, compared to the conventional preparation methods provided in the comparative examples, Examples 1-3 of this invention all incorporate heating circuitry, resulting in faster temperature feedback control and shorter settling time. Through coordinated optimization of materials, structure, and preparation methods, the limitations of traditional technologies are overcome, meeting the precision etching requirements of advanced logic chips and 3D memory chips, and adapting to high-end semiconductor fabrication scenarios.

[0101] The technical principles of the present invention have been described above with reference to specific embodiments. These descriptions are merely for explaining the principles of the invention and should not be construed as limiting the scope of protection of the invention in any way. Based on this explanation, those skilled in the art can readily conceive of other specific embodiments of the invention without inventive effort, and these embodiments will all fall within the scope of protection of the present invention.

Claims

1. A transparent alumina multi-temperature zone built-in heating electrostatic chuck, comprising a metal base, an adhesive layer, and a ceramic body; the adhesive layer is bonded to the upper surface of the metal base; the ceramic body is bonded to the upper surface of the adhesive layer, and the ceramic body includes at least one ceramic dielectric layer; characterized in that: The ceramic dielectric layer is alumina ceramic, which includes the following raw materials in parts by weight: 99.9-99.99 parts of alumina powder, 0.01-0.15 parts of sintering aid, 45-55 parts of solvent, 0.5-2.5 parts of dispersant, 7-11 parts of binder and 4-8 parts of plasticizer. The purity of the alumina powder is above 4N and the particle size of the alumina powder is 150-300nm.

2. The transparent alumina multi-temperature zone built-in heating electrostatic chuck as described in claim 1, characterized in that: The ceramic body includes a first ceramic dielectric layer, an adsorption electrode layer, a second ceramic dielectric layer, a first heating electrode layer, a third ceramic dielectric layer, a second heating electrode layer, and a fourth ceramic dielectric layer arranged sequentially from top to bottom; the upper surface of the first ceramic dielectric layer is provided with a plurality of upwardly protruding protrusions; the fourth ceramic dielectric layer is disposed on the upper surface of the metal base through an adhesive layer.

3. The transparent alumina multi-temperature zone built-in heating electrostatic chuck as described in claim 2, characterized in that: The heating electrode layer adopts a double-layer partitioned conductive metal circuit. The first heating electrode layer is divided into 2-5 main heating zones from the inside out. The circuits in each zone are evenly wired in spiral, planar serpentine, and planar loop shapes, and it uses high-power AC heating. The second heating electrode layer is divided into 2-5 compensation heating ring zones from the inside out. Each compensation heating ring zone is further divided into 40-200 sector zones according to requirements. The circuits in each zone are evenly wired in spiral, planar serpentine, and planar loop shapes, and it uses low-power DC heating. The circuits in each zone are mutually insulated and independently powered.

4. The transparent alumina multi-temperature zone built-in heating electrostatic chuck as described in claim 1, characterized in that: The electrostatic chuck is also provided with multiple helium gas holes, which penetrate the lower and upper surfaces of the ceramic body from bottom to top.

5. A method for preparing a transparent alumina multi-temperature zone built-in heating electrostatic chuck as described in any one of claims 1-4, characterized in that: The method for preparing the ceramic body includes the following steps: (1) Sand milling: According to the raw material composition of the ceramic dielectric layer, take 99.9-99.99 parts of alumina powder, 0.01-0.15 parts of sintering aid, 45-55 parts of solvent and 0.5-2.5 parts of dispersant and put them into the sand mill. Wet ultrafine grinding is carried out at the set speed and time to refine the particle size. After grinding, the material is discharged and filtered to remove coarse particles and impurities to obtain a uniform sand mill slurry. (2) Ball milling: Transfer the sand-milled slurry into a ball milling jar, add 7-11 parts of binder and 4-8 parts of plasticizer, and continue ball milling; then degas the ball-milled slurry to obtain cast slurry; (3) Casting and cutting: The degassed casting slurry is formed using a casting machine to obtain a ceramic green porcelain belt, which is then cut into multiple ceramic green porcelain pieces; (4) Drilling and printing filling: Structural holes and positioning holes are processed on the ceramic raw ceramic sheet; metal paste is printed and filled on the surface of the drilled ceramic raw ceramic sheet using a printing filling machine; (5) Stacking and vacuuming: Stack the printed ceramic raw ceramic pieces and then seal them in plastic; (6) Isostatic pressing: Pressing the plastic-sealed stacked sheets to obtain ceramic green porcelain plates; (7) Debinding: Place the ceramic raw porcelain plate on the corundum mullite firing plate, put it into the debinding furnace, and slowly heat it to 400-500℃ at a heating rate of 0.3-1℃ / min under nitrogen atmosphere, and keep it at the temperature for 3-6 hours to obtain the ceramic debinding sheet. (8) Sintering: The ceramic sheet is placed in a high-temperature sintering furnace and sintered at 1450-1550℃ for 2-4 hours in a hydrogen atmosphere to obtain the ceramic sintered sheet; (9) Machining: The sintered ceramic sheet is machined according to the drawings using machining equipment to obtain a ceramic body with a flatness of <5μm and a surface roughness of <0.1μm.

6. A method for preparing a transparent alumina multi-temperature zone built-in heating electrostatic chuck as described in any one of claims 1-4, characterized in that: The method for preparing the ceramic body includes the following steps: (1) Sand milling: According to the raw material composition of the ceramic dielectric layer, take 99.9-99.99 parts of alumina powder, 0.01-0.15 parts of sintering aid, 45-55 parts of solvent and 0.5-2.5 parts of dispersant and put them into the sand mill. Wet ultrafine grinding is carried out at the set speed and time to refine the particle size. After grinding, the material is discharged and filtered to remove coarse particles and impurities to obtain a uniform sand mill slurry. (2) Ball milling: Transfer the sand mill slurry into a ball milling jar, add 7-11 parts of binder and 4-8 parts of plasticizer, and continue ball milling; then degas the ball-milled slurry to obtain the ball-milled slurry; (3) Granulation: The well-mixed ball mill slurry is granulated using a granulator to obtain granulated powder, which is then screened and batched using a vibrating screen; (4) Isostatic pressing: Pour the obtained granulated powder into a mold, place it in an isostatic press, and press it for 10-30 minutes at 60-80℃ and 180MPa to obtain a ceramic green porcelain plate. (5) Biscuit firing: Place the ceramic green porcelain plate into the sintering furnace, heat it to 900-1000℃ under nitrogen atmosphere, and hold it for 5-6 hours to obtain the ceramic green body; (6) CNC machining: Machining the shape, grooves and positioning structure of the ceramic blank according to the drawings, and controlling the machining allowance; (7) Printing: Using metal paste to print circuits, electrodes and functional layers on the surface of the CNC-machined blank; (8) Hot pressing sintering: The printed blank is placed in a hot pressing sintering furnace and sintered at 1450-1550℃ and 35MPa for 5-6 hours to obtain ceramic sintered parts; (9) Machining: The sintered ceramic sheet is machined according to the drawings using machining equipment to obtain a ceramic body with a flatness of <5μm and a surface roughness of <0.1μm.

7. A method for preparing a transparent alumina multi-temperature zone built-in heating electrostatic chuck as described in any one of claims 1-4, characterized in that: The method for preparing the ceramic body includes the following steps: (1) Sand milling: According to the raw material composition of the ceramic dielectric layer, take 99.9-99.99 parts of alumina powder, 0.01-0.15 parts of sintering aid, 45-55 parts of solvent and 0.5-2.5 parts of dispersant and put them into the sand mill. Wet ultrafine grinding is carried out at the set speed and time to refine the particle size. After grinding, the material is discharged and filtered to remove coarse particles and impurities to obtain a uniform sand mill slurry. (2) Ball milling: Transfer the sand mill slurry into a ball milling jar, add 7-11 parts of binder and 4-8 parts of plasticizer, and continue ball milling; then degas the ball-milled slurry to obtain the ball-milled slurry; (3) Granulation: The well-mixed ball mill slurry is granulated using a granulator to obtain granulated powder, which is then screened and batched using a vibrating screen; (4) Isostatic pressing: Pour the obtained granulated powder into a mold, place it in an isostatic press, and press it for 10-30 minutes at 60-80℃ and 180MPa to obtain a ceramic green porcelain plate. (5) CNC machining: Roughly machine the shape, grooves and positioning structure of the ceramic blank according to the drawings, and control the machining allowance; (6) Carbon removal: The machined green blank is placed in a carbon removal furnace and heated slowly to 400-500℃ at a heating rate of 0.3-1℃ / min under a nitrogen atmosphere. The temperature is held for 3-6 hours to completely decompose the organic binder and other residues in the green blank and obtain ceramic carbon removal sheets. (7) First hot pressing sintering: The carbon-removed blank is placed in a hot pressing sintering furnace and sintered at 1400-1500℃ and 35MPa for 5-6 hours to obtain the initial fired ceramic parts; (8) CNC machining: Precision machining of the shape, grooves and positioning structure of the initial fired ceramic parts; (9) Printing: Using metal paste to print circuits, electrodes and functional layers on the surface of the finished blank; (10) Secondary hot pressing sintering: The printed blank is placed in a hot pressing sintering furnace and sintered at 1450-1550℃ and 35MPa for 5-6 hours to obtain ceramic sintered parts; (11) Machining: The sintered ceramic sheet is machined according to the drawings using machining equipment to obtain a ceramic body with a flatness of <5μm and a surface roughness of <0.1μm.

8. The method for preparing a transparent alumina multi-temperature zone built-in heating electrostatic chuck as described in any one of claims 5-7, characterized in that: The sintering aid is at least one of MgO, magnesium aluminum spinel, and Mg(NO3)2; the solvent is ethanol; the dispersant is at least one of castor oil, tartaric acid oil, polyethylene glycol, and phosphate ester; and the binder is polyvinyl butyral. The plasticizer is at least one of dioctyl phthalate, dimethyl phthalate, dibutyl phthalate, and diisononyl phthalate.

9. The method for preparing a transparent alumina multi-temperature zone built-in heating electrostatic chuck as described in any one of claims 5-7, characterized in that: The metal paste is at least one of platinum, ruthenium, and rhodium.

10. A method for preparing a transparent alumina multi-temperature zone built-in heating electrostatic chuck as described in any one of claims 5-7, characterized in that: The ceramic body and the metal base are assembled through an adhesive layer to form an electrostatic chuck.

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