Glass-ceramics and method for their production and electrostatic chuck

Abstract

The application relates to the technical field of glass ceramic manufacturing and electrostatic chuck technology, and discloses a glass ceramic, a preparation method thereof and an electrostatic chuck. The chemical composition of the glass ceramic provided by the application comprises, based on the total weight of the glass ceramic and in terms of oxides, 23-36 wt% of silicon dioxide, 8-18 wt% of calcium oxide, 5-18 wt% of zinc oxide, 8-16 wt% of aluminum oxide, 0-9 wt% of boron oxide, 4-15 wt% of a first additive and 12-28 wt% of a second additive; wherein the first additive is selected from barium oxide and / or strontium oxide; the second additive is selected from at least one of titanium dioxide, zirconium dioxide and diaphosphorus pentoxide; and the weight ratio of (calcium oxide + first additive) :(silicon dioxide + boron oxide) is greater than or equal to 0.5. The glass ceramic can balance low sintering temperature and electrical insulation performance, has good sintering affinity with an aluminum oxide substrate, and can well meet the performance requirements of the dielectric layer material of the electrostatic chuck with an electrode layer adopting low-melting-point materials.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of glass ceramic manufacturing and electrostatic chuck, and particularly relates to a glass ceramic, a preparation method thereof and an electrostatic chuck. BACKGROUND

[0002] In the processing of semiconductor wafers, stable clamping is needed to ensure processing accuracy, such as PVD, CVD, dry etching and other processes, which need to be operated in a vacuum environment. An electrostatic chuck can fix a semiconductor wafer in a vacuum environment through electrostatic attraction, and is widely used in semiconductor manufacturing devices as a substitute for vacuum chucks and mechanical clamping.

[0003] The structure of an electrostatic chuck mainly includes three parts, from bottom to top, a base layer, an electrode layer and a dielectric layer. In use, a direct current voltage is applied to the electrodes in the electrostatic chuck to generate electrostatic attraction, thereby adsorbing the workpiece on the chuck surface, and desorption is achieved by breaking the power or reversing the electrodes. According to the principle of electrostatic attraction, the adsorption force of the electrostatic chuck is positively correlated with the size of the direct current voltage and the dielectric constant of the material forming the dielectric layer. For the dielectric layer, in order to obtain a large enough adsorption force by applying a larger direct current voltage, it should avoid the generation of leakage current as much as possible, so it is required to have a high bulk resistance value, a high breakdown strength and a low dielectric loss.

[0004] Traditional ceramics such as alumina are used as materials to form the dielectric layer, which have the characteristics of high bulk resistance, high voltage resistance and low dielectric loss, but because of their high sintering temperature, the electrode layer that matches them can only be selected from high-melting-point metal materials such as tungsten, and cannot use silver or copper which have higher thermal conductivity and electrical conductivity, which is not conducive to the processing control of silicon wafers. At present, the dielectric layer material with a lower sintering temperature usually selects borosilicate plus lead oxide or bismuth oxide as the glass composition. The glass containing lead oxide has a low softening temperature and good fluidity, but because it contains lead oxide which has great toxicity and is harmful to the human body and the environment, its use is restricted, and the alternative bismuth oxide also has the risk of being banned. In addition, the electrostatic chuck often uses alumina material (such as 95 / 96 / 99 alumina) as the base layer, and also requires the dielectric layer to have good sintering affinity on the alumina base to achieve firm bonding.

[0005] Therefore, it is of great significance to develop a dielectric layer material that can balance low sintering temperature and electrical insulation, for improving the performance of the electrostatic chuck. SUMMARY

[0006] The application aims to overcome the problem that the sintering temperature of the dielectric layer material of the existing electrostatic chuck is high, which cannot be matched with the low-melting-point electrode layer material, and provides a glass ceramic, a preparation method thereof and an electrostatic chuck.

[0007] To achieve the above-mentioned object, the first aspect of the application provides a glass ceramic, the chemical composition of the glass ceramic, based on the total weight of the glass ceramic, comprises, in terms of oxides, 23-36wt% of silicon dioxide, 8-18wt% of calcium oxide, 5-18wt% of zinc oxide, 8-16wt% of aluminum oxide, 0-9wt% of boron oxide, 4-15wt% of a first additive and 12-28wt% of a second additive.

[0008] The first additive is selected from barium oxide and / or strontium oxide; and the second additive is selected from at least one of titanium dioxide, zirconium dioxide and phosphorus pentoxide.

[0009] The weight ratio of (calcium oxide+first additive):(silicon dioxide+boron oxide) is greater than or equal to 0.5.

[0010] The second aspect of the application provides a preparation method of a glass ceramic, comprising:

[0011] (1) mixing raw material powders, and sequentially melting and cooling the obtained mixture to obtain an intermediate product;

[0012] (2) crushing the intermediate product, and sequentially shaping and sintering the obtained crushed powder to obtain a glass ceramic;

[0013] The total weight of the raw material powders, in terms of oxides, comprises 23-36wt% of silicon dioxide, 8-18wt% of calcium oxide, 5-18wt% of zinc oxide, 8-16wt% of aluminum oxide, 0-9wt% of boron oxide, 4-15wt% of a first additive and 12-28wt% of a second additive.

[0014] The first additive is selected from barium oxide and / or strontium oxide; and the second additive is selected from at least one of titanium dioxide, zirconium dioxide and phosphorus pentoxide.

[0015] The weight ratio of (calcium oxide+first additive):(silicon dioxide+boron oxide) is greater than or equal to 0.5.

[0016] The third aspect of the application provides a glass ceramic prepared by the preparation method of the second aspect.

[0017] The fourth aspect of the application provides an electrostatic chuck, comprising a substrate, an electrode layer and a dielectric layer.

[0018] Wherein, the dielectric layer is the glass ceramic described in the first aspect or the third aspect.

[0019] Through the above scheme, the glass ceramic provided by the present invention can achieve both low sintering temperature and electrical insulation performance without containing lead and bismuth elements. The glass ceramic has a low glass transition temperature and has the characteristics of being sintered at a relatively low temperature of 800-950°C. The volume resistivity of the glass ceramic at 25°C and 1000V is 1×10 14 -8×10 15 Ω / cm; the dielectric constant at 13.56MHz is 8-11; the dielectric loss at 1MHz is (0.4-1)×10 -3 The electrical breakdown strength in a silicone oil medium at 25°C is 30-49 kV / mm, demonstrating excellent electrical insulation properties. This glass-ceramic exhibits excellent sintering compatibility with alumina and good wettability on the surface of alumina substrates. It is suitable not only for 95 / 96 alumina substrates but also for 99 high-purity alumina substrates with a lower glass phase content. Based on these characteristics, the glass-ceramic provided by the present invention can well meet the performance requirements for dielectric layer materials in electrostatic chucks whose electrode layers utilize low-melting-point materials such as silver and copper. DETAILED DESCRIPTION

[0020] The endpoints of the ranges and any values ​​disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoints of each range, the endpoints of each range and individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered to be specifically disclosed herein.

[0021] A first aspect of the present invention provides a glass ceramic, wherein the chemical composition of the glass ceramic, calculated as oxides, comprises: 23-36 wt% silicon dioxide, 8-18 wt% calcium oxide, 5-18 wt% zinc oxide, 8-16 wt% aluminum oxide, 0-9 wt% boron oxide, 4-15 wt% first additive, and 12-28 wt% second additive, based on the total weight of the glass ceramic;

[0022] Wherein, the first auxiliary agent is selected from barium oxide and / or strontium oxide; the second auxiliary agent is selected from at least one of titanium dioxide, zirconium dioxide and phosphorus pentoxide;

[0023] The weight ratio of (calcium oxide + first auxiliary agent): (silicon dioxide + boron oxide) is ≥0.5.

[0024] According to the present application, in the chemical composition of the glass ceramic, the content of silicon dioxide (SiO2) as the network former of the glass ceramic is positively correlated with the viscosity of the glass melt. The content of silicon dioxide is 23-36 wt%, preferably 28-32 wt% based on the total weight of the glass ceramic.

[0025] According to the present application, in the chemical composition of the glass ceramic, calcium oxide (CaO) and the first additive (selected from BaO and / or SrO) jointly reduce the high-temperature viscosity of the glass melt, improve the sintering density of the glass ceramic, and enable the glass ceramic to have suitable electrical properties. The content of calcium oxide is 8-18 wt%, preferably 13-16 wt%, and the content of the first additive is 4-15 wt%, preferably 4.7-8.1 wt%, based on the total weight of the glass ceramic.

[0026] According to the present application, preferably, the first additive is barium oxide.

[0027] According to the present application, in the chemical composition of the glass ceramic, zinc oxide (ZnO) helps to improve the sintering density and chemical stability of the glass ceramic, and enables the glass ceramic to have a suitable coefficient of thermal expansion. The content of zinc oxide is 5-18 wt%, preferably 13-16 wt%, based on the total weight of the glass ceramic.

[0028] According to the present application, in the chemical composition of the glass ceramic, aluminum oxide (Al2O3) improves the chemical stability of the glass ceramic and reduces the high-temperature viscosity of the glass melt. An appropriate amount of Al2O3 reduces the tendency of the glass ceramic to crystallize at low temperatures and adjusts the crystallization process. The content of aluminum oxide is 8-16 wt%, preferably 13-15 wt%, based on the total weight of the glass ceramic.

[0029] According to the present application, in the chemical composition of the glass ceramic, optional boron oxide (B2O3) further forms the network structure of the glass ceramic together with silicon dioxide. The content of boron oxide is 0-9 wt%, preferably 0-5 wt%, based on the total weight of the glass ceramic.

[0030] According to the present application, in the chemical composition of the glass ceramic, the second additive (at least one of TiO2, ZrO2, and P2O5) helps to form appropriate crystals during the sintering process of the glass ceramic, and improves the strength and corrosion resistance of the glass ceramic. The content of the second additive is 12-28 wt%, preferably 16-20 wt%, based on the total weight of the glass ceramic.

[0031] According to the present application, preferably, the second additive is titanium dioxide and zirconium dioxide.

[0032] According to the present application, preferably, the weight ratio of (calcium oxide + first auxiliary agent) : (silicon dioxide + boron oxide) in the glass ceramic is ≥ 0.5 and ≤ 0.9, based on the total weight of the glass ceramic.

[0033] According to the present application, preferably, the chemical composition of the glass ceramic comprises, based on the total weight of the glass ceramic, 28-32 wt% silicon dioxide, 13-16 wt% calcium oxide, 13-16 wt% zinc oxide, 13-15 wt% aluminum oxide, 0-5 wt% boron oxide, 4.7-8.1 wt% first auxiliary agent and 16-20 wt% second auxiliary agent, based on the total weight of the glass ceramic.

[0034] According to the present application, the glass ceramic contains trace amounts of impurity elements which do not affect the performance of the glass ceramic.

[0035] For the glass ceramic provided by the present application, although the roles of the above-mentioned components contained therein can be considered, the inventors of the present application have found that when the glass ceramic contains the above-mentioned specific chemical composition and content and satisfies the specific component quantity relationship, the components can cooperate with each other to produce a synergistic effect, so that the glass ceramic can have low sintering temperature, excellent electrical insulation performance and good sintering affinity with an aluminum oxide substrate. When the chemical composition of the glass ceramic and the component quantity relationship do not satisfy the above-mentioned specific ranges, the glass ceramic product having the performance parameters of the present application and the above-mentioned comprehensive performance effects cannot be obtained.

[0036] According to the present application, the glass ceramic has a low sintering temperature and can be sintered at 800-950°C. For an electrostatic chuck with an electrode layer made of low-melting-point materials such as silver and copper, the glass ceramic provided by the present application can be used as a dielectric layer of an electrostatic chuck with an electrode layer made of low-melting-point materials such as silver and copper.

[0037] According to the present application, the glass ceramic has a large volume resistance. Preferably, the volume resistance of the glass ceramic at 25°C and 1000V is 1 x 10 14 -8 x 10 15 Ω / cm, and further preferably 4 x 10 15 -8 x 10 15 Ω / cm.

[0038] In the present application, the volume resistance is measured by a high resistance meter.

[0039] According to the present application, the glass ceramic has a high electrical breakdown strength. Preferably, the electrical breakdown strength of the glass ceramic in silicone oil medium at 25°C is 30-49 kV / mm, further preferably 40-49 kV / mm.

[0040] In the present application, the electrical breakdown strength is determined according to the method specified in GB / T 1408.1-2016 Insulating materials - Determination of electrical strength.

[0041] According to the present application, the glass ceramic has a large dielectric constant. Preferably, the dielectric constant of the glass ceramic at 13.56 MHz is 8-11, further preferably 9.5-11.

[0042] In the present application, the dielectric constant is determined by an impedance analyzer.

[0043] According to the present application, the glass ceramic has a low dielectric loss. Preferably, the dielectric loss of the glass ceramic at 1 MHz is (0.4-1) x 10 -3 , preferably (0.4-0.8) x 10 -3 .

[0044] In the present application, the dielectric loss is determined according to the method specified in GB / T 5594.4-2015.

[0045] According to the present application, the glass ceramic has good sintering affinity with the alumina substrate, has good wettability on the surface of the alumina substrate, and further binds closely with the alumina substrate. The material of the alumina substrate includes but is not limited to 95 alumina, 96 alumina and 99 alumina.

[0046] According to a particularly preferred embodiment of the present application, based on the total weight of the glass ceramic, the chemical composition of the glass ceramic comprises, in terms of oxides, 29-31 wt% of silicon dioxide, 14-16 wt% of calcium oxide, 13-15 wt% of zinc oxide, 13-15 wt% of aluminum oxide, 0-5 wt% of boron oxide, 4.7-5 wt% of a first additive and 18-20 wt% of a second additive; wherein the weight ratio of (calcium oxide + first additive) : (silicon dioxide + boron oxide) is (0.57-0.68) : 1; the first additive is barium oxide; and the second additive is zirconium dioxide and titanium dioxide. By using the above-mentioned particularly preferred embodiment, the sintering temperature of the glass ceramic can be realized at 850-870°C, the volume resistance at 25°C, 1000V is 5.9 x 10 15 -8 x 10 15 Ω / cm, the electrical breakdown strength in silicone oil medium at 25°C is 43.6-49 kV / mm, the dielectric constant at 13.56 MHz is 9.5-11, and the dielectric loss at 1 MHz is 0.4 x 10-3 -0.8x10 -3 .

[0047] The glass ceramic provided by the present application has the specific chemical composition and comprehensive performance index described above, low sintering temperature, excellent electrical performance, and can be used as a dielectric layer material of an electrostatic chuck, which can match with an electrode layer made of a material with lower melting point (for example, silver and copper with high thermal conductivity and high electrical conductivity), thereby improving the adsorption force and heat dissipation capacity of the electrostatic chuck, and better meeting the processing control requirements of semiconductor silicon wafers.

[0048] The second aspect of the present application provides a preparation method of a glass ceramic, comprising:

[0049] (1) mixing raw material powders, and sequentially melting and cooling the obtained mixture to obtain an intermediate product;

[0050] (2) crushing the intermediate product, and sequentially forming and sintering the obtained crushed powder to obtain a glass ceramic;

[0051] wherein, based on the total weight of the raw material powders, the raw material powders comprise, in terms of oxides, 23-36wt% of silicon dioxide, 8-18wt% of calcium oxide, 5-18wt% of zinc oxide, 8-16wt% of aluminum oxide, 0-9wt% of boron oxide, 4-15wt% of a first additive, and 12-28wt% of a second additive;

[0052] wherein, the first additive is selected from barium oxide and / or strontium oxide; and the second additive is selected from at least one of titanium dioxide, zirconium dioxide, and diaphosphorus pentoxide;

[0053] the weight ratio of (calcium oxide + first additive) :(silicon dioxide + boron oxide) is ≥0.5.

[0054] According to the present application, the raw material powders can respectively provide the above-mentioned oxides, and can adopt conventional raw material types in the field of glass or ceramics, which are not particularly limited in the present application. For example, silicon dioxide, zinc oxide, aluminum oxide, titanium dioxide, and zirconium dioxide can be respectively fed in the form of oxides of Si, Zn, Al, Ti, and Zr; calcium oxide, barium oxide, and strontium oxide can be respectively fed in the form of carbonates of Ca, Ba, and Sr; boron oxide can be fed in the form of an oxide of B or anhydrous boric acid; and diaphosphorus pentoxide can be fed in the form of ammonium dihydrogen phosphate or aluminum phosphate.

[0055] According to the present application, preferably, based on the total weight of the raw material powders, in the raw material powders, in terms of oxides, the weight ratio of (calcium oxide + first additive) :(silicon dioxide + boron oxide) is ≥0.5, and the weight ratio of (calcium oxide + first additive) :(silicon dioxide + boron oxide) is ≤0.9.

[0056] According to the present application, preferably, the raw material powder comprises, based on the total weight of the glass ceramic, 28-32wt% of silicon dioxide, 13-16wt% of calcium oxide, 13-16wt% of zinc oxide, 13-15wt% of aluminum oxide, 0-5wt% of boron oxide, 4.7-8.1wt% of the first additive and 16-20wt% of the second additive.

[0057] According to a particularly preferred embodiment of the present application, the raw material powder comprises, based on the total weight of the glass ceramic, 29-31wt% of silicon dioxide, 14-16wt% of calcium oxide, 13-15wt% of zinc oxide, 13-15wt% of aluminum oxide, 0-5wt% of boron oxide, 4.7-5wt% of the first additive and 18-20wt% of the second additive; wherein the weight ratio of (calcium oxide + the first additive) : (silicon dioxide + boron oxide) is (0.57-0.68) : 1; the first additive is barium oxide; and the second additive is titanium dioxide and zirconium dioxide. The use of this particularly preferred embodiment can make the prepared glass ceramic have low sintering temperature, better electrical insulation performance and better sintering affinity with the aluminum oxide substrate.

[0058] According to the present application, preferably, the average particle size of the raw material powder is 1-20μm, and further preferably 5-10μm. In the present application, the average particle size refers to D50, which can be measured by a laser particle size analyzer.

[0059] According to the present application, the mixing method of the raw material powder is not particularly limited, and a conventional mixing method can be used as long as a uniform mixture can be obtained, for example, grinding blending, mechanical stirring and the like can be used.

[0060] According to the present application, the melting is performed in air atmosphere or oxygen-rich atmosphere for the purpose of melting the mixture into a liquid state. Preferably, the melting conditions include a temperature of 1400-1700℃, and preferably 1500-1600℃, and a time of 0.5-4h, and preferably 1-2h.

[0061] In the present application, in order to obtain better melting effect, preferably, before the melting is performed, the mixture is first heated to 200-300℃ at a heating rate of 5-10℃ / min and kept for 60-120min to sufficiently remove water, and then heated to 1000-1200℃ at a heating rate of 5-10℃ / min and kept for 10-60min, and then heated to the required temperature for the melting to perform the melting.

[0062] According to the present application, the cooling is not particularly limited, and can be air cooling, water cooling, or the like, as long as the molten product can be rapidly cooled to obtain the intermediate product in the form of a lump.

[0063] According to the present application, the intermediate product is a glass in the form of a lump.

[0064] According to the present application, the intermediate product is not particularly limited, and can be crushed by a conventional crushing method, including but not limited to grinding, mechanical crushing, or the like. Preferably, the crushing treatment is performed such that the particle size of the crushed powder obtained satisfies D50≤4μm, preferably D50≤2μm; and D95≤10μm, preferably D95≤5μm.

[0065] According to the present application, the forming is not particularly limited, and can be performed by a conventional glass or ceramic forming process, for example, the crushed powder can be mixed with a binder, and then subjected to dry pressing or screen printing, and preferably formed into the appearance shape of a dielectric layer for an electrostatic chuck.

[0066] In the present application, the binder is not particularly limited, and preferably at least one of castor oil, dibutyl phthalate, a 3-5wt% polyvinyl butyral (PVB) ethanol solution, and a 3-8wt% ethyl cellulose terpineol solution.

[0067] According to the present application, the sintering can be performed in a variety of sintering atmospheres, for example, a vacuum atmosphere, an air atmosphere, or an inert atmosphere, and is preferably performed in an air atmosphere.

[0068] According to the present application, the sintering can be performed in a conventional sintering device, and the present application is not particularly limited thereto.

[0069] According to the present application, the sintering can be performed in a plurality of temperature stages, and preferably includes a first sintering and a second sintering.

[0070] The first sintering is performed at a temperature of 650-750℃, preferably 680-720℃, for a time of 0.5-2h, preferably 0.5-1h.

[0071] The second sintering is performed at a temperature of 800-950℃, preferably 850-900℃, for a time of 0.5-2h, preferably 0.5-1h.

[0072] Preferably, the temperature of the first sintering is 100-200℃ lower than the temperature of the second sintering.

[0073] According to the present application, preferably, before the sintering, the sintering object is first heated to 450-550℃ at a heating rate of 1-2℃ / min for 120-240min to remove the glue, and then heated to the required sintering temperature for the sintering.

[0074] The third aspect of the present application provides a glass ceramic prepared by the preparation method of the second aspect. The composition and performance indicators of the glass ceramic prepared by the method are the same as those of the glass ceramic described in the first aspect of the present application, which will not be repeated here.

[0075] The fourth aspect of the present application provides an electrostatic chuck, comprising a substrate, an electrode layer and a dielectric layer.

[0076] The dielectric layer is the glass ceramic of the first aspect or the third aspect.

[0077] The electrostatic chuck provided by the present application not only meets the performance required for normal operation, but also has the advantages of good compatibility with electrode materials, low sintering temperature, low energy consumption of preparation process and green and non-toxic preparation materials.

[0078] The present application will be described in detail below by way of examples. In the following examples and comparative examples,

[0079] The content of each chemical component in the prepared glass ceramic is calculated by the amount of raw materials.

[0080] Unless otherwise specified, the materials used are ordinary commercially available products.

[0081] Example 1

[0082] Raw materials: based on the total weight of the raw material powder, the chemical composition of 29.35wt% of silicon dioxide, 14.99wt% of calcium oxide, 13.63wt% of zinc oxide, 13.63wt% of aluminum oxide, 4.81wt% of boron oxide, 4.72wt% of first additive and 18.87wt% of second additive (wherein the first additive is barium oxide and the second additive is titanium dioxide 10.48wt%+zirconium dioxide 8.39wt%) is respectively weighed as raw material powder (average particle size 5-10μm) according to the chemical composition of silicon dioxide, calcium carbonate, zinc oxide, aluminum oxide, anhydrous boric acid, barium carbonate, titanium dioxide and zirconium dioxide.

[0083] (1-1) The above raw material powder is added to a ball mill tank, and according to the weight ratio of raw material powder: grinding ball of 1:1.5, agate grinding balls are added, and then placed in a grinding machine for grinding and blending for 4h to obtain a mixture;

[0084] (1-2) The mixture is placed in a 99 alumina crucible, a glass rod is repeatedly inserted into the mixture to create pores as heat and gas exchange channels, then the crucible is placed in a muffle furnace, the temperature is raised to 240°C at a rate of 10°C / min and held for 60 min, then the temperature is continuously raised to 1200°C at a rate of 10°C / min and held for 10 min, then the temperature is raised to 1600°C at a rate of 5°C / min and held for 1 h for melting; after the melting is completed, the crucible is taken out, the glass liquid in the crucible is poured into deionized water for cooling, and a broken block-shaped intermediate product is obtained;

[0085] (2-1) The intermediate product is wet ground (using water as the medium, the weight ratio of the intermediate product to the zirconia grinding balls is 1:2) for 24 h, and after discharging, the broken powder (denoted as M1, with a D50 of 2 μm and a D95 of 5 μm) is obtained. A 1% PVB ethanol solution (PVB concentration of 5 wt%) is added to the broken powder, and then dry pressing is performed to form a disc;

[0086] (2-2) The disc is placed in a muffle furnace, degassing is performed in an air atmosphere at a temperature of 550°C for 240 min at a rate of 2°C / min, then first sintering is performed at a temperature of 694°C for 1 h at a rate of 5°C / min, then second sintering is performed at a temperature of 850°C for 1 h at a rate of 10°C / min, and a glass-ceramic (denoted as P1) is obtained.

[0087] In addition, the broken powder M1 and printing glue (92 wt% ethyl cellulose in pine oil (ethyl cellulose concentration of 5 wt%) + 3 wt% castor oil + 5 wt% dibutyl phthalate) are prepared into a paste at a weight ratio of 4:1 and uniformly coated on a 99 alumina ceramic disc, and then sintered under the same sintering conditions as the disc to obtain a sintering affinity test sample (denoted as T1).

[0088] The chemical components of P1 (in terms of oxides) are shown in Table 1.

[0089] Example 2

[0090] Raw materials: Based on the total weight of the raw material powder, the chemical composition of 30.83 wt% silicon dioxide, 15.75 wt% calcium oxide, 14.32 wt% zinc oxide, 14.32 wt% aluminum oxide, 4.96 wt% first additive, and 19.82 wt% second additive (wherein the first additive is barium oxide and the second additive is 11.01 wt% titanium dioxide + 8.81 wt% zirconium dioxide) in terms of oxides are respectively weighed as raw material powders (average particle size of 5-10 μm) of silicon dioxide, calcium carbonate, zinc oxide, aluminum oxide, barium carbonate, titanium dioxide, and zirconium dioxide.

[0091] (1-1) The above raw material powder was added to a ball mill tank, and according to the weight ratio of raw material powder: grinding ball of 1:1.5, agate grinding balls were added, and then placed in a mill for grinding and blending for 4 h to obtain a mixture;

[0092] (1-2) The above mixture was placed in a 99 alumina crucible, and a glass rod was repeatedly inserted into the mixture to create pores as heat and gas exchange channels; then the crucible was placed in a muffle furnace, and the temperature was raised to 240°C at a rate of 10°C / min for 60 min, and then continued to be raised to 1200°C at a rate of 10°C / min for 10 min, and then raised to 1550°C at a rate of 5°C / min for 1.5 h for melting; after the melting was completed, the crucible was taken out, and the glass liquid in it was poured into deionized water for cooling to obtain a broken block-shaped intermediate product;

[0093] (2-1) The above intermediate product was wet ground (using water as a medium, the weight ratio of intermediate product: zirconia grinding ball was 1:2) for 24 h, and after discharging, the broken powder (denoted as M2, with a D50 of 1.6 μm and a D95 of 4.8 μm) was obtained. In the above broken powder, 1% by weight of a PVB ethanol solution (PVB concentration of 5 wt%) was added, and then dry pressing was performed to form a disc;

[0094] (2-2) The above disc was placed in a muffle furnace, and in an air atmosphere, the temperature was raised to 550°C at a rate of 2°C / min for 240 min for degassing, and then continued to be raised to 710°C at a rate of 5°C / min for 40 min for first sintering, and then raised to 870°C at a rate of 10°C / min for 1 h for second sintering to obtain a glass-ceramic (denoted as P2).

[0095] In addition, the above broken powder M2 was mixed with printing glue (92 wt% ethyl cellulose in terpineol solution (ethyl cellulose concentration of 5 wt%) + 3 wt% castor oil + 5 wt% dibutyl phthalate) at a weight ratio of 4:1 to prepare a paste, and uniformly coated on a 99 alumina ceramic sheet, and then sintered under the same sintering conditions as the above disc to obtain a sintering affinity test sample (denoted as T2).

[0096] The chemical components of P2 (in terms of oxides) are shown in Table 1.

[0097] Example 3

[0098] Raw materials: With the total weight of raw material powder as the basis, the chemical composition of 28.30wt% of silicon dioxide, 13.80wt% of calcium oxide, 15.26wt% of zinc oxide, 14.60wt% of aluminum oxide, 3.55wt% of boron oxide, 8.05wt% of the first additive, and 16.44wt% of the second additive (wherein the first additive is barium oxide, and the second additive is 12.84wt% of titanium dioxide + 3.60wt% of zirconium dioxide) were respectively weighed as raw material powder (average particle size of 5-10μm) of silicon dioxide, calcium carbonate, zinc oxide, aluminum oxide, anhydrous boric acid, barium carbonate, titanium dioxide, and zirconium dioxide.

[0099] (1-1) The above raw material powder was added to a ball mill tank, and 1:1.5 of raw material powder: grinding ball was added to the agate grinding ball, and then placed in the mill for grinding and blending for 4h to obtain a mixture;

[0100] (1-2) The above mixture was placed in a 99 alumina crucible, and a glass rod was repeatedly inserted into the mixture to create pores as heat and gas exchange channels; then the crucible was placed in a muffle furnace, and the temperature was raised to 240℃ at a rate of 10℃ / min for 60min, and then continued to be raised to 1200℃ at a rate of 10℃ / min for 10min, and then raised to 1500℃ at a rate of 5℃ / min for 2h for melting; after the melting was completed, the crucible was taken out, and the glass liquid in it was poured into deionized water for cooling to obtain a broken block-shaped intermediate product;

[0101] (2-1) The above intermediate product was wet ground (using water as the medium, the weight ratio of intermediate product: zirconium oxide grinding ball was 1:2) for 24h, and after discharging, the broken powder (denoted as M3, with D50 of 1.9μm and D95 of 4.6μm) was obtained; 1% of PVB ethanol solution (PVB concentration of 5wt%) was added to the above broken powder, and then dry pressing was performed to form a disc;

[0102] (2-2) The above disc was placed in a muffle furnace, and degassing was performed in an air atmosphere at a temperature of 550℃ for 240min at a rate of 2℃ / min, and then first sintering was performed at a temperature of 680℃ for 1h at a rate of 5℃ / min, and then second sintering was performed at a temperature of 880℃ for 0.5h at a rate of 10℃ / min to obtain a glass-ceramic (denoted as P3).

[0103] Further, the above broken powder M3 was mixed with printing gum (92 wt% ethyl cellulose in a solution of terpineol (ethyl cellulose concentration 5 wt%) + 3 wt% castor oil + 5 wt% dibutyl phthalate) in a weight ratio of 4:1 to prepare a paste, which was uniformly coated on a 99 alumina ceramic wafer, and then sintered under the same sintering conditions as the above wafer to obtain a sintering affinity test sample (denoted as T3).

[0104] The chemical components of P3 (in terms of oxides) are shown in Table 1.

[0105] Example 4

[0106] Raw materials: Based on the total weight of the raw material powder, the chemical composition of 35.70 wt% silicon dioxide, 17.60 wt% calcium oxide, 10.20 wt% zinc oxide, 8.00 wt% aluminum oxide, 8.30 wt% boron oxide, 4.40 wt% first additive, and 15.80 wt% second additive (wherein the first additive is barium oxide and the second additive is 7.80 wt% titanium dioxide + 8.00 wt% zirconium dioxide) in terms of oxides were respectively weighed as raw material powders (average particle size 1-20 μm) of silicon dioxide, calcium carbonate, zinc oxide, aluminum oxide, anhydrous boric acid, barium carbonate, titanium dioxide, and zirconium dioxide.

[0107] (1-1) The above raw material powder was added to a ball mill tank, and 1:1.5 of agate grinding balls were added according to the weight ratio of raw material powder: grinding balls, and then placed in a mill for grinding and blending for 4 h to obtain a mixture;

[0108] (1-2) The above mixture was placed in a 99 alumina crucible, and a glass rod was repeatedly inserted into the mixture to create pores as heat and gas exchange channels; then the crucible was placed in a muffle furnace, and the temperature was raised to 250°C at a rate of 10°C / min and held for 60 min, then the temperature was further raised to 1200°C at a rate of 10°C / min and held for 20 min, and then the temperature was raised to 1400°C at a rate of 5°C / min and held for 4 h for melting; after the melting was completed, the crucible was removed, and the glass liquid in it was poured into deionized water for cooling to obtain a chunky intermediate product;

[0109] (2-1) The above intermediate product was wet ground (using water as a medium, the weight ratio of intermediate product: zirconia grinding balls was 1:2) for 24 h, and after discharging, the broken powder (denoted as M4, with a D50 of 1.9 μm and a D95 of 4.8 μm) was obtained; 1% of an ethanol solution of PVB (PVB concentration 5 wt%) was added to the above broken powder, and then dry pressing was performed to form a wafer;

[0110] (2-2) The above disc was placed in a muffle furnace, and heated to 550°C at a temperature increasing rate of 2°C / min in an air atmosphere for 240 min to perform degumming, and then heated to 650°C at a temperature increasing rate of 5°C / min for 1.5 h to perform first sintering, and then heated to 800°C at a temperature increasing rate of 10°C / min for 2 h to perform second sintering, to obtain a glass ceramic (denoted as P4).

[0111] Further, the above broken powder M4 was mixed with printing gum (92 wt% of a solution of ethyl cellulose in terpineol (ethyl cellulose concentration of 5 wt%) + 3 wt% of castor oil + 5 wt% of dibutyl phthalate) at a weight ratio of 4:1 to prepare a paste, which was uniformly coated on a 99 alumina ceramic disc, and then sintered under the same sintering conditions as the above disc to obtain a sintering affinity test sample (denoted as T4).

[0112] The chemical components of P4 (in terms of oxides) are shown in Table 1.

[0113] Example 5

[0114] Raw materials: Based on the total weight of the raw material powder, the chemical composition of 33.8 wt% of silicon dioxide, 10.20 wt% of calcium oxide, 5.43 wt% of zinc oxide, 9.20 wt% of aluminum oxide, 5.70 wt% of boron oxide, 14.29 wt% of the first additive, and 21.38 wt% of the second additive (wherein the first additive is 6.81 wt% of barium oxide + 7.48 wt% of strontium oxide, and the second additive is 10.52 wt% of titanium dioxide + 5.62 wt% of zirconium dioxide + 5.24 wt% of phosphorus pentoxide) was prepared by weighing silicon dioxide, calcium carbonate, zinc oxide, aluminum oxide, anhydrous boric acid, barium carbonate, strontium carbonate, titanium dioxide, zirconium dioxide, and ammonium dihydrogen phosphate as raw material powders (average particle size of 1-20 μm).

[0115] (1-1) The above raw material powder was added to a ball mill tank, and 1:1.5 of raw material powder: grinding ball was added to the tank, and then placed in a grinder to grind and blend for 4 h to obtain a mixture;

[0116] (1-2) The above mixture was placed in a 99 alumina crucible, and a glass rod was repeatedly inserted into the mixture to create pores as heat and gas exchange channels; then the crucible was placed in a muffle furnace, and heated to 250°C at a temperature increasing rate of 10°C / min for 60 min, and then heated to 1200°C at a temperature increasing rate of 10°C / min for 20 min, and then heated to 1650°C at a temperature increasing rate of 5°C / min for 0.5 h to perform melting; after the melting was completed, the crucible was taken out, and the glass liquid therein was poured into deionized water to cool, to obtain a broken block-shaped intermediate product;

[0117] (2-1) The intermediate product was wet-milled (using water as the medium, intermediate product: zirconia grinding balls at a weight ratio of 1:2) for 24 h, and the broken powder (denoted as M5, with a D50 of 2 μm and a D95 of 4.9 μm) was obtained after drying and discharging; 1% of PVB ethanol solution (PVB concentration of 5 wt%) was added to the broken powder, and then the mixture was dry-pressed into a disc;

[0118] (2-2) The disc was placed in a muffle furnace, and the disc was heated to 550°C at a heating rate of 2°C / min in an air atmosphere for 240 min to remove the resin, and then the disc was heated to 725°C at a heating rate of 5°C / min for 0.5 h for first sintering, and then the disc was heated to 920°C at a heating rate of 10°C / min for 0.5 h for second sintering, to obtain a glass ceramic (denoted as P5).

[0119] In addition, the broken powder M5 and printing glue (92 wt% of a solution of ethyl cellulose in pine oil (ethyl cellulose concentration of 5 wt%) + 3 wt% of castor oil + 5 wt% of dibutyl phthalate) were mixed at a weight ratio of 4:1 to prepare a paste, and the paste was uniformly coated on a 99 alumina ceramic disc, and then the disc was sintered under the same sintering conditions as the disc to obtain a sintering affinity test sample (denoted as T5).

[0120] The chemical components of P5 (in terms of oxides) are shown in Table 1.

[0121] Example 6

[0122] Raw materials: based on the total weight of the raw material powder, the chemical composition of 23.00 wt% of silicon dioxide, 8.94 wt% of calcium oxide, 17.60 wt% of zinc oxide, 8.20 wt% of aluminum oxide, 2.60 wt% of anhydrous boric acid, 12.31 wt% of the first additive, and 27.35 wt% of the second additive (wherein the first additive is 1.88 wt% of barium oxide + 10.43 wt% of strontium oxide, and the second additive is 10.28 wt% of titanium dioxide + 6.63 wt% of zirconium dioxide + 10.44 wt% of phosphorus pentoxide) were respectively weighed as raw material powders (average particle size of 1-20 μm) of silicon dioxide, calcium carbonate, zinc oxide, aluminum oxide, anhydrous boric acid, barium carbonate, strontium carbonate, titanium dioxide, zirconium dioxide, and aluminum phosphate.

[0123] (1-1) The raw material powder was added to a ball mill tank, and 1.5 times the weight of the raw material powder of agate grinding balls was added, and then the mixture was ground and blended in a mill for 4 h to obtain a mixture;

[0124] (1-2) Put the above mixture into a 99 alumina crucible, repeatedly insert a glass rod into the mixture to make pores as heat and gas exchange channels; then put the crucible into a muffle furnace, raise the temperature to 250°C at a rate of 10°C / min, keep for 60 min, then continue to raise the temperature to 1200°C at a rate of 10°C / min, keep for 30 min, then raise the temperature to 1700°C at a rate of 5°C / min, keep for 0.5 h for melting; after the melting is completed, take out the crucible, pour the glass liquid in the crucible into deionized water for cooling, and obtain a broken block-shaped intermediate product;

[0125] (2-1) Wet mill the above intermediate product (use water as medium, the weight ratio of intermediate product to zirconia grinding ball is 1:2) for 24 h, dry the discharged material to obtain a broken powder (denoted as M6, the D50 is 1.3 μm, and the D95 is 4.4 μm); add 1% of PVB ethanol solution (the PVB concentration is 5 wt%) by weight of the broken powder to the broken powder, then dry-press into a disc;

[0126] (2-2) Put the above disc into a muffle furnace, raise the temperature to 550°C at a rate of 2°C / min in an air atmosphere, keep for 240 min for degassing, then continue to raise the temperature to 674°C at a rate of 5°C / min, keep for 0.5 h for first sintering, then raise the temperature to 810°C at a rate of 10°C / min, keep for 2 h for second sintering, and obtain a glass ceramic (denoted as P6).

[0127] In addition, the broken powder M6 and printing glue (92 wt% of pine oil solution of ethyl cellulose (the ethyl cellulose concentration is 5 wt%) + 3 wt% of castor oil + 5 wt% of dibutyl phthalate) are prepared into a paste at a weight ratio of 4:1, and uniformly coated on a 99 alumina ceramic disc, then sintered under the same sintering conditions as the above disc to obtain a sintering affinity test sample (denoted as T6).

[0128] The chemical components (in terms of oxides) of P6 are shown in Table 1.

[0129] Example 7

[0130] The method and parameters of Example 1 were followed, except that the raw material powders were weighed according to the chemical composition ratio of 24.07 wt% of silica, 14.99 wt% of calcium oxide, 13.63 wt% of zinc oxide, 13.63 wt% of aluminum oxide, 4.81 wt% of boron oxide, 10.00 wt% of the first additive, and 18.87 wt% of the second additive (wherein the first additive is barium oxide and the second additive is 10.48 wt% of titanium dioxide + 8.39 wt% of zirconium dioxide) based on the total weight of the raw material powders (average particle size of 5-10 μm) in terms of oxides. The other conditions were the same as in Example 1. As a result, the crushed powder (denoted as M7, D50 of 2 μm, and D95 of 5 μm) was obtained in step (2-1), and 1% of the PVB ethanol solution (PVB concentration of 5 wt%) based on the weight of the crushed powder was added, followed by dry pressing into a disc. The glass-ceramic (denoted as P7) was finally obtained in step (2-2).

[0131] In addition, the crushed powder M7 was mixed with printing gum (92 wt% of ethyl cellulose in a solution of terpineol (ethyl cellulose concentration of 5 wt%) + 3 wt% of castor oil + 5 wt% of dibutyl phthalate) at a weight ratio of 4:1 to prepare a paste, which was uniformly coated on a 99 alumina ceramic disc, followed by sintering under the same sintering conditions as the disc described above to obtain a sintering affinity test sample (denoted as T7).

[0132] The chemical components of P7 (in terms of oxides) are shown in Table 1.

[0133] Example 8

[0134] The method and parameters of Example 1 were followed, except that the raw material powders were weighed according to the chemical composition ratio of 24.07 wt% of silica, 14.99 wt% of calcium oxide, 13.63 wt% of zinc oxide, 13.63 wt% of aluminum oxide, 4.81 wt% of boron oxide, 10.00 wt% of the first additive, and 18.87 wt% of the second additive (wherein the first additive is barium oxide and the second additive is 10.48 wt% of titanium dioxide + 8.39 wt% of zirconium dioxide) based on the total weight of the raw material powders (average particle size of 5-10 μm) in terms of oxides. The other conditions were the same as in Example 1. As a result, the crushed powder (denoted as M7, D50 of 2 μm, and D95 of 5 μm) was obtained in step (2-1), and 1% of the PVB ethanol solution (PVB concentration of 5 wt%) based on the weight of the crushed powder was added, followed by dry pressing into a disc. The glass-ceramic (denoted as P7) was finally obtained in step (2-2).

[0135] Further, the above broken powder M8 was mixed with printing ink (92 wt% ethyl cellulose solution in terpineol (ethyl cellulose concentration 5 wt%) + 3 wt% castor oil + 5 wt% dibutyl phthalate) at a weight ratio of 4:1 to prepare a paste, which was uniformly coated on 99 alumina ceramic tablets, and then sintered under the same sintering conditions as the above tablets to obtain a sintering affinity test sample (denoted as T8).

[0136] The chemical components of P7 (in terms of oxides) are shown in Table 1.

[0137] Comparative Example 1

[0138] The method and parameters of Example 1 were followed, except that the raw material powders were weighed according to the chemical composition of 45.60 wt% silicon dioxide, 6.89 wt% calcium oxide, 8.42 wt% zinc oxide, 10.09 wt% aluminum oxide, 1.00 wt% boron anhydride, 16.41 wt% first additive (barium oxide), and 11.59 wt% second additive (6.01 wt% titanium dioxide + 5.58 wt% zirconium dioxide) in terms of oxides, based on the total weight of the raw material powders. The silicon dioxide, calcium carbonate, zinc oxide, aluminum oxide, anhydrous boric acid, barium carbonate, titanium dioxide, and zirconium dioxide were weighed as raw material powders (average particle size 5-10 μm) with the above chemical composition. The other conditions were the same as in Example 1. The broken powder (denoted as DM1, with D50 of 2 μm and D95 of 5 μm) was obtained in step (2-1), and an ethanol solution of PVB (PVB concentration 5 wt%) was added to the broken powder at 1% by weight, followed by dry pressing into tablets. The glass-ceramics (denoted as DP1) were finally obtained in step (2-2).

[0139] Further, the above broken powder DM1 was mixed with printing ink (92 wt% ethyl cellulose solution in terpineol (ethyl cellulose concentration 5 wt%) + 3 wt% castor oil + 5 wt% dibutyl phthalate) at a weight ratio of 4:1 to prepare a paste, which was uniformly coated on 99 alumina ceramic tablets, and then sintered under the same sintering conditions as the above tablets to obtain a sintering affinity test sample (denoted as DT1).

[0140] The chemical components of DP1 (in terms of oxides) are shown in Table 1.

[0141] Comparative Example 2

[0142] The method and parameters of Example 1 were followed, except that the raw powders were prepared by weighing 35.03 wt% of silica, 10.40 wt% of calcium oxide, 13.31 wt% of zinc oxide, 13.31 wt% of aluminum oxide, 5.90 wt% of boron oxide, 4.70 wt% of the first additive, and 17.35 wt% of the second additive (wherein the first additive is barium oxide and the second additive is 10.60 wt% of titanium dioxide + 6.75 wt% of zirconium dioxide) based on the total weight of the raw powders, in terms of oxides. The other conditions were the same as in Example 1. The broken powder (denoted as DM2, with a D50 of 2 μm and a D95 of 5 μm) was obtained in step (2-1), and 1% of PVB in ethanol (with a PVB concentration of 5 wt%) was added to the broken powder, followed by dry pressing into a disc. The glass-ceramic (denoted as DP2) was finally obtained in step (2-2).

[0143] In addition, the broken powder DM2 was mixed with printing gum (92 wt% of ethyl cellulose in terpineol (with a ethyl cellulose concentration of 5 wt%) + 3 wt% of castor oil + 5 wt% of dibutyl phthalate) at a weight ratio of 4:1 to form a paste, which was uniformly coated on a 99 alumina ceramic disc, followed by sintering under the same sintering conditions as the disc to obtain a sintering affinity test sample (denoted as DT2).

[0144] The chemical components of DP2 (in terms of oxides) are shown in Table 1.

[0145] Test Example

[0146] 1. Electrical property test

[0147] The glass-ceramics P1-P8 and DP1-DP2 obtained in Examples 1-8 and Comparative Examples 1-2 were subjected to volume resistance test (at 25°C and 1000V), electrical breakdown strength test (in silicon oil medium at 25°C), dielectric constant test (at 13.56 MHz), and dielectric loss test (at 1 MHz), and the results are shown in Table 1.

[0148] 2. Sintering affinity test with alumina

[0149] The sintering affinity test samples T1-T8 and DT1-DT2 obtained in Examples 1-8 and Comparative Examples 1-2 were cut to obtain flat cross sections, and a metal spatula was placed on the interface between the glass-ceramic coating and the alumina substrate in each cross section, and the pressure was applied and increased to 200 N. The above process was repeated 10 times, and no peeling was denoted as O, and peeling was denoted as X. The results are shown in Table 1.

[0150] The weight percentages in Table 1 are based on the total weight of the glass-ceramic.

[0151] Table 1 Table 1 (continued)

[0152]

[0153]

[0154] As can be seen from Table 1, the glass-ceramic products P1-P8 provided by Examples 1-8 of the present application exhibit excellent electrical insulation, while having high volume resistance, electrical breakdown strength, dielectric constant and low dielectric loss, and low sintering temperature (800-950℃), and good sintering affinity on an alumina (especially 99 alumina) substrate, and can be well matched with low-melting-point, high-performance electrode layer materials, and can well meet the performance requirements of the electrode layer on the dielectric layer material of the electrostatic chuck using silver, copper and other low-melting-point materials, thereby improving the adsorption force of the electrostatic chuck, wherein Examples 1-3 exhibit significant comprehensive performance advantages. In particular, the glass-ceramic product DP1 prepared from Comparative Example 1 does not satisfy the limited conditions of the present application in terms of the proportion of the components contained therein, and the performance is significantly poorer than that of P1-P8; the glass-ceramic product DP2 prepared from Comparative Example 2 has a weight ratio of (calcium oxide + first additive) : (silicon dioxide + boron oxide) < 0.5, and the effect is poor.

[0155] The above describes preferred embodiments of the present application, but the present application is not limited thereto. Within the technical concept of the present application, various simple modifications can be made to the technical solutions of the present application, including the combination of various technical features in any other suitable manner, and these simple modifications and combinations should also be considered as disclosed by the present application, and all fall within the protection scope of the present application.

Claims

1. A glass ceramic for an electrostatic chuck, characterized in that: Based on the total weight of the glass ceramic, the chemical composition of the glass ceramic, calculated as oxides, includes: 23-36 wt% of silicon dioxide, 8-18 wt% of calcium oxide, 5-18 wt% of zinc oxide, 8-16 wt% of aluminum oxide, 0-9 wt% of boron oxide, 4-15 wt% of a first additive, and 12-28 wt% of a second additive; Wherein, the first auxiliary agent is selected from barium oxide and / or strontium oxide; the second auxiliary agent is selected from at least one of titanium dioxide, zirconium dioxide and phosphorus pentoxide; The weight ratio of (calcium oxide + first additive): (silicon dioxide + boron oxide) is ≥ 0.5; The volume resistance of the glass ceramic at 25°C and 1000V is 1×10 14 -8×10 15 Ω / cm; The glass ceramic has an electrical breakdown strength of 30-49 kV / mm in a silicone oil medium at 25°C; The dielectric constant of the glass ceramic at 13.56 MHz is 8-11; The dielectric loss of the glass ceramic at 1 MHz is (0.4-1)×10 -3 ; The electrostatic chuck has an alumina substrate.

2. The glass ceramic according to claim 1, wherein Based on the total weight of the glass ceramic, the chemical composition of the glass ceramic, calculated as oxides, includes: 28-32 wt% silicon dioxide, 13-16 wt% calcium oxide, 13-16 wt% zinc oxide, 13-15 wt% aluminum oxide, 0-5 wt% boron oxide, 4.7-8.1 wt% first auxiliary agent and 16-20 wt% second auxiliary agent.

3. The glass ceramic according to claim 1 or 2, wherein The volume resistance of the glass ceramic at 25°C and 1000V is 4×10 15 -8×10 15 Ω / cm.

4. The glass ceramic according to claim 1 or 2, wherein The glass ceramic has an electrical breakdown strength of 40-49 kV / mm in a silicone oil medium at 25°C.

5. The glass ceramic according to claim 1 or 2, wherein The glass ceramic has a dielectric constant of 9.5-11 at 13.56 MHz.

6. The glass ceramic according to claim 1 or 2, wherein The dielectric loss of the glass ceramic at 1 MHz is (0.4-0.8)×10 -3 .

7. A method for preparing glass ceramics for electrostatic chucks, characterized in that: include: (1) mixing raw material powders, and sequentially melting and cooling the obtained mixture to obtain an intermediate product; (2) crushing the intermediate product, and sequentially molding and sintering the obtained crushed powder to obtain glass ceramics; Wherein, based on the total weight of the raw material powder, the raw material powder includes, in terms of oxides: 23-36 wt% of silicon dioxide, 8-18 wt% of calcium oxide, 5-18 wt% of zinc oxide, 8-16 wt% of aluminum oxide, 0-9 wt% of boron oxide, 4-15 wt% of a first auxiliary agent, and 12-28 wt% of a second auxiliary agent; Wherein, the first auxiliary agent is selected from barium oxide and / or strontium oxide; the second auxiliary agent is selected from at least one of titanium dioxide, zirconium dioxide and phosphorus pentoxide; The weight ratio of (calcium oxide + first additive): (silicon dioxide + boron oxide) is ≥ 0.5; The electrostatic chuck has an alumina substrate.

8. The method according to claim 7, wherein: Based on the total weight of the glass ceramic, the raw material powder includes, in terms of oxides: 28-32wt% silicon dioxide, 13-16wt% calcium oxide, 13-16wt% zinc oxide, 13-15wt% aluminum oxide, 0-5wt% boron oxide, 4.7-8.1wt% first auxiliary agent and 16-20wt% second auxiliary agent.

9. The method according to claim 7 or 8, wherein The average particle size of the raw material powder is 1-20 μm.

10. The method according to claim 9, wherein: The average particle size of the raw material powder is 5-10 μm.

11. The method according to claim 7 or 8, wherein: The melting conditions include: a temperature of 1400-1700° C.; and a time of 0.5-4 hours.

12. The method according to claim 11, wherein The melting conditions include: a temperature of 1500-1600° C.; and a time of 1-2 hours.

13. The method according to claim 7 or 8, wherein: The crushed powder has a D50 of ≤4 μm and a D95 of ≤10 μm.

14. The method according to claim 13, wherein: The crushed powder has a D50 of ≤2 μm and a D95 of ≤5 μm.

15. The method according to claim 7 or 8, wherein The sintering includes a first sintering and a second sintering; The first sintering conditions include: temperature of 650-750° C.; time of 0.5-2 h; The second sintering conditions include: temperature of 800-950° C.; time of 0.5-2 h.

16. The method according to claim 15, wherein The first sintering conditions include: temperature of 680-720° C.; time of 0.5-1 h; The second sintering conditions include: temperature of 850-900° C.; time of 0.5-1 h.

17. A glass ceramic for an electrostatic chuck produced by the method according to any one of claims 7 to 16.

18. An electrostatic chuck, characterized in that: The electrostatic chuck comprises: an alumina substrate, an electrode layer and a dielectric layer; Wherein, the dielectric layer is the glass ceramic for electrostatic chuck according to any one of claims 1-6 and 17.

Images