Glue discharging method for electrostatic chuck green body

Abstract

The invention discloses a glue discharging method for an electrostatic chuck green body, and belongs to the technical field of electrostatic chucks, and the glue discharging method comprises the steps that S1, the electrostatic chuck green body is prepared, and then the electrostatic chuck green body is evenly placed in a glue discharging box; s2, air is introduced into the glue discharging box, and then the temperature in the glue discharging box is increased to a certain temperature at a certain heating rate; and S3, switching air introduced into the glue discharging box into nitrogen, and raising the temperature in the glue discharging box to a certain temperature at a certain temperature raising rate. The invention provides a glue discharging method for an electrostatic chuck, and solves the problems of internal cracks or non-uniform electrical property and mechanical property of a product during firing due to high carbon residue of the product and poor uniformity of the product after the organic matters are not thoroughly removed and glue is discharged in the existing glue discharging process method.

Description

Technical Field

[0001] The invention relates to the technical field of electrostatic chucks, and in particular to a method for removing binder from a green body of an electrostatic chuck. Background Art

[0002] The electrostatic chuck is formed by laminating and sintering ceramic dielectric diaphragms with printed electrode slurry to form a ceramic disc. Before the product is sintered into ceramic, it needs to be debinded. Debinding is to remove the organic solvent substances inside the green body by reaction or volatilization through high-temperature airflow to ensure the quality and effect during high-temperature sintering. The quality of debinding directly affects the uniformity of the internal structure of the product after sintering, thereby affecting the performance and quality of the product. The existing debinding atmosphere usually uses nitrogen. Due to the complex composition of organic matter inside the green body, it is difficult to remove all organic matter with a single atmosphere. The maximum temperature of nitrogen debinding can be set to above 550℃, which can directly crack large molecular weight organic matter, but the slow removal rate of small molecular organic matter in nitrogen atmosphere can easily lead to high carbon residue in the product. Therefore, a debinding method for electrostatic chuck green body is needed to reduce debinding carbon residue. Summary of the invention

[0003] The technical problem to be solved by the present invention is to provide a method for debinding a green body of an electrostatic chuck, which can reduce the residual carbon in the debinding of the ceramic green body of the electrostatic chuck.

[0004] In order to solve the above technical problems, the technical solution of the present invention is:

[0005] A method for debinding a green blank of an electrostatic chuck, the method comprising:

[0006] S1: preparing an electrostatic chuck green body, and then evenly placing the electrostatic chuck green body in a binder removal box;

[0007] S2: Air is introduced into the debinding box, and then the temperature in the debinding box is raised to a certain temperature at a certain heating rate, specifically:

[0008] Heat the air and pass it into the binder removal box. First, raise the temperature in the binder removal box to 200°C at a rate of 0.5-0.7°C / min, then raise the temperature in the binder removal box to 250°C at a rate of 0.06-0.1°C / min; then raise the temperature in the binder removal box to 300°C at a rate of 0.025-0.029°C / min, and keep the temperature in the binder removal box at 300°C for 2 hours. During the entire binder removal process in the air atmosphere, the pressure in the binder removal box is 6-20Pa;

[0009] S3: Switch the air entering the debinding box to nitrogen, and then raise the temperature in the debinding box to a certain temperature at a certain heating rate, specifically:

[0010] 180L / min of nitrogen is introduced into the binder removal box to expel the air and keep the oxygen content below 10ppm. The pressure in the binder removal box is continued to be maintained in the range of 6-20Pa. The temperature in the binder removal box is increased to 400°C at a heating rate of 0.024-0.026°C / min, and is kept at 400°C for 4h. Then, the temperature in the binder removal box is increased to 500°C at a heating rate of 0.082-0.084°C / min, and is kept at 500°C for 2h. Then, the temperature in the binder removal box is reduced to 200°C at a cooling rate of 0.8-1.2°C / min. Air is introduced below 200°C to cool the temperature in the binder removal box to room temperature, thereby obtaining an electrostatic chuck with completed binder removal.

[0011] Preferably, the method for preparing the electrostatic chuck green body in step S1 comprises:

[0012] The ceramic powder and the organic solvent are uniformly dispersed to make a ceramic slurry, wherein the organic solvent includes a binder, a dispersant, a plasticizer, and a defoamer, and the slurry is made into a ceramic diaphragm by casting;

[0013] A layer of inner electrode is covered on the ceramic diaphragm by screen printing, and then the protective layer without printed electrode is subjected to isostatic pressing, punching, hole filling and cutting to obtain an electrostatic chuck green body.

[0014] Preferably, in step S2: air is introduced into the binder removal box, the temperature in the binder removal box is first raised to 200°C at a rate of 0.6°C / min, and then the temperature in the binder removal box is raised to 250°C at a rate of 0.08°C / min; then the temperature in the binder removal box is raised to 300°C at a rate of 0.027°C / min, and the temperature in the binder removal box is kept at 300°C for 2h.

[0015] Preferably, in S3: the air introduced into the debinding box is switched to nitrogen, 180 L / min of nitrogen is introduced into the debinding box to expel the air and keep the oxygen content below 10 ppm, the temperature in the debinding box is raised to 400°C at a heating rate of 0.025°C / min, and kept at 400°C for 4 hours; then the temperature in the debinding box is raised to 500°C at a heating rate of 0.083°C / min, and kept at 500°C for 2 hours, and then the temperature in the debinding box is lowered to 200°C at a cooling rate of 1°C / min.

[0016] The above technical solution has the following beneficial effects:

[0017] The present invention provides a debinding method for an electrostatic chuck, which solves the problems that the existing debinding process method does not remove organic matter cleanly, the carbon residue of the product after debinding is high, the product uniformity is poor, and the internal cracks or uneven electrical and mechanical properties of the product during firing are caused;

[0018] The present invention provides a debinding method for an electrostatic chuck, wherein the method comprises: preparing an electrostatic chuck green body, and evenly placing the electrostatic chuck green body in a debinding box; introducing air into the debinding box, and raising the temperature in the debinding box to 300°C within a preset time period; switching the air introduced into the debinding box to nitrogen, and raising the temperature in the debinding box to 500°C within a preset time period; switching the nitrogen introduced into the debinding box to air, and lowering the temperature in the debinding box to room temperature, to obtain an electrostatic chuck with debinding completed. Compared with the single atmosphere debinding, the present invention can better remove organic matter inside the electrostatic chuck green body by switching the atmosphere debinding midway, shorten the debinding time, improve the debinding efficiency, and save costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a structural schematic diagram of the binder removal equipment of the present invention. DETAILED DESCRIPTION

[0020] The specific embodiments of the present invention are further described below in conjunction with the accompanying drawings. It should be noted that the description of these embodiments is used to help understand the present invention, but does not constitute a limitation of the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0021] Example 1

[0022] A method for debinding a green blank of an electrostatic chuck, the method comprising:

[0023] S1: preparing an electrostatic chuck green body, and then evenly placing the electrostatic chuck green body in a binder removal box;

[0024] S2: Air is introduced into the debinding box, and then the temperature in the debinding box is raised to a certain temperature at a certain heating rate, specifically:

[0025] The heated air is introduced into the debinding box, and the temperature in the debinding box is first raised to 200°C at a rate of 0.5-0.7°C / min, and then raised to 250°C at a rate of 0.06-0.1°C / min; then raised to 300°C at a rate of 0.025-0.029°C / min, and the temperature in the debinding box is kept at 300°C for 2 hours. The pressure in the debinding box is 6-20Pa during the entire debinding process in the air atmosphere;

[0026] S3: Switch the air entering the debinding box to nitrogen, and then raise the temperature in the debinding box to a certain temperature at a certain heating rate, specifically:

[0027] 180L / min of nitrogen is introduced into the binder removal box to expel the air and keep the oxygen content below 10ppm. The pressure in the binder removal box is continued to be maintained in the range of 6-20Pa. The temperature in the binder removal box is increased to 400°C at a heating rate of 0.024-0.026°C / min, and is kept at 400°C for 4h; then the temperature in the binder removal box is increased to 500°C at a heating rate of 0.082-0.084°C / min, and is kept at 500°C for 2h, and then the temperature in the binder removal box is reduced to 200°C at a cooling rate of 0.8-1.2°C / min. Air is introduced below 200°C to cool the temperature in the binder removal box down to room temperature, thereby obtaining an electrostatic chuck with completed binder removal.

[0028] Example 2

[0029] A method for debinding a green blank of an electrostatic chuck, the method comprising:

[0030] S1: preparing an electrostatic chuck green body, and then evenly placing the electrostatic chuck green body in a binder removal box;

[0031] S2: Air is introduced into the debinding box, and then the temperature in the debinding box is raised to a certain temperature at a certain heating rate, specifically:

[0032] The heated air is introduced into the debinding box, and the temperature in the debinding box is first raised to 200°C at a rate of 0.6°C / min, and then raised to 250°C at a rate of 0.08°C / min; then raised to 300°C at a rate of 0.027°C / min, and the temperature in the debinding box is kept at 300°C for 2 hours. The pressure in the debinding box is 13Pa during the entire debinding process in the air atmosphere;

[0033] S3: Switch the air entering the debinding box to nitrogen, and then raise the temperature in the debinding box to a certain temperature at a certain heating rate, specifically:

[0034] 180L / min of nitrogen was introduced into the binder removal box to expel the air and keep the oxygen content below 10ppm. The pressure in the binder removal box was maintained at 13Pa. The temperature in the binder removal box was raised to 400℃ at a heating rate of 0.025℃ / min and kept at 400℃ for 4h. The temperature in the binder removal box was then raised to 500℃ at a heating rate of 0.083℃ / min and kept at 500℃ for 2h. The temperature in the binder removal box was then lowered to 200℃ at a cooling rate of 1℃ / min. Air was introduced below 200℃ to cool the temperature in the binder removal box down to room temperature, thereby obtaining an electrostatic chuck with completed binder removal.

[0035] Example 3

[0036] A method for debinding a green blank of an electrostatic chuck, the method comprising:

[0037] S1: preparing an electrostatic chuck green body, and then evenly placing the electrostatic chuck green body in a binder removal box;

[0038] S2: Air is introduced into the debinding box, and then the temperature in the debinding box is raised to a certain temperature at a certain heating rate, specifically:

[0039] The heated air is introduced into the debinding box, and the temperature in the debinding box is first raised to 200°C at a rate of 0.5°C / min, and then raised to 250°C at a rate of 0.06°C / min; then raised to 300°C at a rate of 0.025°C / min, and the temperature in the debinding box is kept at 300°C for 2 hours. The pressure in the debinding box is 6Pa during the entire debinding process in the air atmosphere;

[0040] S3: Switch the air entering the debinding box to nitrogen, and then raise the temperature in the debinding box to a certain temperature at a certain heating rate, specifically:

[0041] 180L / min of nitrogen was introduced into the binder removal box to expel the air and keep the oxygen content below 10ppm. The pressure in the binder removal box was kept within the range of 6Pa. The temperature in the binder removal box was raised to 400℃ at a heating rate of 0.024℃ / min and kept at 400℃ for 4h. The temperature in the binder removal box was then raised to 500℃ at a heating rate of 0.082℃ / min and kept at 500℃ for 2h. The temperature in the binder removal box was then lowered to 200℃ at a cooling rate of 0.8℃ / min. Air was introduced below 200℃ to cool the temperature in the binder removal box down to room temperature, thereby obtaining an electrostatic chuck with completed binder removal.

[0042] Example 4

[0043] A method for debinding a green blank of an electrostatic chuck, the method comprising:

[0044] S1: preparing an electrostatic chuck green body, and then evenly placing the electrostatic chuck green body in a binder removal box;

[0045] S2: Air is introduced into the debinding box, and then the temperature in the debinding box is raised to a certain temperature at a certain heating rate, specifically:

[0046] The heated air is introduced into the debinding box, and the temperature in the debinding box is first raised to 200°C at a rate of 0.7°C / min, and then raised to 250°C at a rate of 0.1°C / min; then raised to 300°C at a rate of 0.029°C / min, and the temperature in the debinding box is kept at 300°C for 2 hours. The pressure in the debinding box is 20Pa during the entire debinding process in the air atmosphere;

[0047] S3: Switch the air entering the debinding box to nitrogen, and then raise the temperature in the debinding box to a certain temperature at a certain heating rate, specifically:

[0048] 180L / min of nitrogen was introduced into the binder removal box to expel the air and keep the oxygen content below 10ppm. The pressure in the binder removal box was kept within the range of 20Pa. The temperature in the binder removal box was raised to 400℃ at a heating rate of 0.026℃ / min and kept at 400℃ for 4h. The temperature in the binder removal box was then raised to 500℃ at a heating rate of 0.084℃ / min and kept at 500℃ for 2h. The temperature in the binder removal box was then lowered to 200℃ at a cooling rate of 1.2℃ / min. Air was introduced below 200℃ to cool the temperature in the binder removal box down to room temperature, thereby obtaining an electrostatic chuck with completed binder removal.

[0049] The present application provides a debinding method for an electrostatic chuck, which solves the problem that the existing debinding process method does not completely remove organic matter, resulting in high carbon residue in the product after debinding, poor product uniformity, and internal cracks or uneven electrical and mechanical properties of the product during firing;

[0050] The debinding method for an electrostatic chuck of the present application comprises the following steps: firstly preparing an electrostatic chuck green body, and evenly placing the electrostatic chuck green body in a debinding box, introducing air into the debinding box, and raising the temperature in the debinding box to 300° C. within a preset time period; switching the air introduced into the debinding box to nitrogen, and raising the temperature in the debinding box to 500° C. within a preset time period; switching the nitrogen introduced into the debinding box to air, and lowering the temperature in the debinding box to room temperature, and obtaining an electrostatic chuck with debinding completed. Compared with the single atmosphere debinding of the prior art, the technical solution of the present application can better remove organic matter inside the electrostatic chuck green body by switching the atmosphere debinding in the middle, shortening the debinding time, improving the debinding efficiency, and saving costs;

[0051] The method of measuring weight loss rate is adopted. The present application adopts a binder removal method of air atmosphere plus nitrogen atmosphere. Compared with the binder removal method under a single nitrogen atmosphere adopted in the prior art, the weight loss rate of the binder removal method in the present application is significantly greater than the existing binder removal process, that is, by adopting the technical solution of the present application, organic matter is removed more cleanly, and a ceramic product with low carbon residue and good product uniformity can be obtained. The specific comparison is shown in Table 1:

[0052] Table 1

[0053]

[0054]

[0055] Under the condition of the same initial weight, the weight loss rate when debinding using nitrogen atmosphere alone is 12.53%, while the weight loss rate under the debinding method of air plus nitrogen atmosphere in the present application is 13.64%, which has a higher weight loss rate. Under another condition of the same weight, the weight loss rate of debinding using nitrogen atmosphere alone is 12.16%, and the weight loss rate under the debinding method of air plus nitrogen atmosphere in the present application is 13.88%, which is significantly higher than the debinding method of nitrogen atmosphere alone in the prior art.

[0056] Example 5

[0057] refer to Figure 1 , is a schematic diagram of the debinding equipment of the present application, wherein the mass flow meter is used to control the flow rate of nitrogen;

[0058] The debinding equipment comprises a main air intake pipe 3, a nitrogen air intake pipe 1 and an air air intake pipe 2. The nitrogen air intake pipe 1 and the air air intake pipe 2 are both connected to the main air intake pipe 3. The nitrogen air intake pipe 1 is provided with a first pressure gauge 5 and a mass flow meter 7. The first pressure gauge 5 is arranged near the air intake end. The nitrogen air intake pipe 1 is also provided with a first solenoid valve 8 and a third solenoid valve 11. The air intake pipe 2 is provided with a second pressure gauge 6, a second solenoid valve 9, a fourth solenoid valve 10 and a heating water passage 12 in sequence. The second pressure gauge 6 is close to the inlet. The main air intake pipe 3 is provided with a heating wire 13. The gas in the main air intake pipe 3 enters the debinding box 14 through the heating wire 13. The glue box 14 is connected to the exhaust pipe 4, and the exhaust pipe 4 is provided with an air handling device 15. The nitrogen intake pipe 1 and the air intake pipe 2 are crossed and connected together at the intersection. The second solenoid valve 9 and the fourth solenoid valve 10 are respectively on both sides of the intersection, and the first solenoid valve 8 and the third solenoid valve 11 are also distributed on both sides of the intersection. The heating wire 13 is used to control the temperature of the gas input into the glue removal box 14, and then control the temperature in the glue removal box 14. The first solenoid valve 8, the third solenoid valve 11, the second solenoid valve 9, and the fourth solenoid valve 10 are used to control the switching process between air and nitrogen and the selection of whether to humidify. At present, the main atmosphere modes are as follows:

[0059] 1. Dry nitrogen mode: the mass flow meter 7 is turned on, the first solenoid valve 8 and the third solenoid valve 11 are opened, and the dry nitrogen enters the binder removal box 14 after being heated;

[0060] 2. Dry air mode: the second solenoid valve 9 and the fourth solenoid valve 10 are opened, and the dry air enters the binder removal box 14 after being heated;

[0061] 3. Wet nitrogen mode: the mass flow meter 7 is turned on, the first solenoid valve 8 and the third solenoid valve 11 are opened, and the nitrogen enters the debinding box through the humidifying barrel 12;

[0062] Wet air mode: the second solenoid valve 9 and the fourth solenoid valve 10 are opened, and the air enters the binder removal box through the humidifying barrel 12;

[0063] The weight loss rate was measured and compared with the existing debinding process. The weight loss rate of this method was significantly greater than that of the existing debinding process.

[0064] The embodiments of the present invention are described in detail above with reference to the accompanying drawings, but the present invention is not limited to the described embodiments. For those skilled in the art, various changes, modifications, substitutions and variations of these embodiments are made without departing from the principles and spirit of the present invention, and still fall within the scope of protection of the present invention.

Claims

1. A method for debinding a green body of an electrostatic chuck, characterized in that: The method comprises: S1: preparing an electrostatic chuck green body, and then evenly placing the electrostatic chuck green body in a binder removal box; S2: Air is introduced into the debinding box, and then the temperature in the debinding box is raised to a certain temperature at a certain heating rate, specifically: Heat the air and pass it into the binder removal box. First, raise the temperature in the binder removal box to 200°C at a heating rate of 0.5-0.7°C / min, then raise the temperature in the binder removal box to 250°C at a heating rate of 0.06-0.1°C / min, and then raise the temperature in the binder removal box to 300°C at a rate of 0.025-0.029°C / min. Keep the temperature in the binder removal box at 300°C for 2 hours. During the entire binder removal process in the air atmosphere, the pressure in the binder removal box is 6-20Pa. S3: Switch the air entering the debinding box to nitrogen, and then raise the temperature in the debinding box to a certain temperature at a certain heating rate, specifically: 180L / min of nitrogen is introduced into the binder removal box to expel the air and keep the oxygen content below 10ppm. The pressure in the binder removal box is continued to be maintained in the range of 6-20Pa. The temperature in the binder removal box is increased to 400°C at a heating rate of 0.024-0.026°C / min, and is kept at 400°C for 4h. Then, the temperature in the binder removal box is increased to 500°C at a heating rate of 0.082-0.084°C / min, and is kept at 500°C for 2h. Then, the temperature in the binder removal box is reduced to 200°C at a cooling rate of 0.8-1.2°C / min. Air is introduced below 200°C to cool the temperature in the binder removal box to room temperature, thereby obtaining an electrostatic chuck with completed binder removal.

2. A method for debinding a green body of an electrostatic chuck according to claim 1, characterized in that: The method for preparing the electrostatic chuck green body in step S1 comprises: The ceramic powder and the organic solvent are uniformly dispersed to make a ceramic slurry, wherein the organic solvent includes a binder, a dispersant, a plasticizer, and a defoamer, and the slurry is made into a ceramic diaphragm by casting; A layer of inner electrode is covered on the ceramic diaphragm by screen printing, and then the protective layer without printed electrode is subjected to isostatic pressing, punching, hole filling and cutting to obtain an electrostatic chuck green body.

3. A method for debinding a green body of an electrostatic chuck according to claim 1, characterized in that: In the step S2: air is introduced into the binder removal box, the temperature in the binder removal box is first raised to 200°C at a rate of 0.6°C / min, and then the temperature in the binder removal box is raised to 250°C at a rate of 0.08°C / min; then the temperature in the binder removal box is raised to 300°C at a rate of 0.027°C / min, and the temperature in the binder removal box is kept at 300°C for 2 hours.

4. A method for debinding a green body of an electrostatic chuck according to claim 1, characterized in that: In S3: the air introduced into the debinding box is switched to nitrogen, 180 L / min of nitrogen is introduced into the debinding box to exhaust the air and make the oxygen content below 10 ppm, the temperature in the debinding box is increased to 400° C. at a heating rate of 0.025° C. / min, and kept at 400° C. for 4 hours; Then, the temperature in the debinding box was raised to 500°C at a heating rate of 0.083°C / min, and kept at 500°C for 2 hours, and then the temperature in the debinding box was lowered to 200°C at a cooling rate of 1°C / min.

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