Electrostatic chuck

Abstract

The utility model discloses an electrostatic chuck, which belongs to the technical field of semiconductors and comprises a base and a ceramic plate, electrodes are arranged in the ceramic plate, the base is connected with the ceramic plate through a bonding layer, an insulating layer is arranged on one side, facing the ceramic plate, of the base, a heating assembly is arranged between the base and the ceramic plate, and the heating assembly is connected with the ceramic plate. The electrostatic chuck can ensure the normal heating work of the heater, reduce the production cost and improve the thickness uniformity of each part of the bonding layer. The heating assembly is arranged between the base and the ceramic plate, the heating assembly is directly attached to the ceramic plate, the heater can be arranged to be in a needed shape, and compared with an external heater, heating is more uniform, and heat loss is reduced; the insulating layer is arranged on the side, facing the ceramic plate, of the base, so that the heater and the base can be separated, and communication between the base and the heater is avoided.

Description

Technical Field

[0001] The utility model relates to the technical field of semiconductors, in particular to an electrostatic chuck. Background Art

[0002] The electrostatic chuck is composed of a ceramic plate, a heater and a base, which is used to adsorb the wafer and adjust the temperature of the wafer. As the feature size of the device continues to shrink, the manufacturing process temperature of the device gradually increases, so temperature regulation becomes crucial. The heater is an important part for regulating temperature. Previously, the electrostatic chuck heater mainly used a method in which the heater was built into the ceramic or an external heater. The built-in heater is directly installed inside the ceramic, which requires very high sintering technology for the ceramic, so it is difficult to prepare. External electrostatic chucks are mostly prepared by wrapping metal resistance wire with insulating material. This preparation method will cause the heater to be too far away from the ceramic plate, resulting in poor heating effect. In addition, the ceramic plate and the base are connected by an adhesive layer, but the thickness of the adhesive layer is difficult to keep consistent everywhere. Utility Model Content

[0003] The technical problem to be solved by the utility model is to provide an electrostatic chuck, which can ensure the normal heating work of the heater, reduce the production cost and improve the uniformity of the thickness of each part of the bonding layer.

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

[0005] An electrostatic chuck comprises a base and a ceramic plate, wherein the ceramic plate is provided with an electrode, the base is connected to the ceramic plate via an adhesive layer, an insulating layer is provided on the side of the base facing the ceramic plate, and a heating component is provided between the base and the ceramic plate.

[0006] Preferably, the heating assembly comprises a heater, the heater is arranged between the base and the ceramic plate, and the adhesive layer is provided with a hollow portion cooperating with the heater.

[0007] Preferably, the thickness of the heater is equal to the thickness of the adhesive layer.

[0008] Preferably, the ceramic plate is made of insulating ceramic material with a resistivity higher than 10 16 Ω·cm.

[0009] Preferably, the heater is made of metal material.

[0010] Preferably, the heater has a thickness of 50-500 μm.

[0011] Preferably, the insulating layer is made by anodizing or thermal spraying.

[0012] The above technical solution has the following beneficial effects:

[0013] 1. By setting a heating component between the base and the ceramic plate, the heating component is directly attached to the ceramic plate, and the heater can be set into a required shape. Compared with an external heater, the heating is more uniform and the heat loss is reduced;

[0014] 2. By placing the heater between the ceramic plate and the base, the production cost of the product can be reduced compared to the commonly used method of building the heater into the ceramic plate;

[0015] 3. By providing an insulating layer on the side of the base facing the ceramic plate, the heater and the base can be separated to prevent the base from being connected to the heater. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a cross-sectional structural schematic diagram of the electrostatic chuck of the utility model;

[0017] Figure 2 It is a structural schematic diagram of the heater of the utility model. DETAILED DESCRIPTION

[0018] The specific implementation methods of the present invention are further described below in conjunction with the accompanying drawings. It should be noted that the description of these implementation methods 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 each implementation method of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0019] like Figure 1 , Figure 2 As shown, Figure 1 This is a schematic cross-sectional view of the electrostatic chuck of the utility model. Figure 2 The utility model is a schematic diagram of the structure of the heater, which includes a base 1 and a ceramic plate 2, wherein the ceramic plate 2 is provided with an electrode, the base 1 and the ceramic plate 2 are connected by an adhesive layer 5, and the adhesive layer 5 is formed by drying the adhesive bonding the base 1 and the ceramic plate 2, an insulating layer 3 is provided on the side of the base 1 facing the ceramic plate 2, a heating component is provided between the base 1 and the ceramic plate 2, and a pattern can be provided on the side of the ceramic plate 2 away from the substrate as needed;

[0020] The heating assembly includes a heater 4, which is arranged between the base 1 and the ceramic plate 2. The adhesive layer 5 is provided with a hollow portion that matches the heater 4. The heater 4 is arranged between the base 1 and the ceramic plate 2. Compared with the currently common method of embedding the heater 4 in the ceramic plate 2, the processing cost and processing difficulty can be reduced. Compared with the external heater 4, it can heat more evenly, reduce heat loss during the heating process, and improve energy utilization efficiency. The adhesive layer 5 is provided with a hollow portion that matches the heater 4. The shape of the heater 4 can be set according to actual conditions, such as being set to metal rings that are connected to each other in order from small to large, and the gaps between metal rings of different sizes are the adhesive layer 5. The largest metal ring and the outer wall ring of the ceramic plate 2 are also the adhesive layer 5. In order to ensure that the substrate and the ceramic plate 2 can be bonded more firmly, the largest metal ring of the heater 4 is set according to actual conditions to ensure that there is enough adhesive between the substrate and the ceramic plate 2 and to ensure the area of ​​the adhesive layer.

[0021] The thickness of the heater 4 is equal to that of the adhesive layer 5. The heater 4 can be a thin sheet structure. The adhesive layer 5 is provided with a hollow that matches the heater 4. Since the ceramic plate 2 is in the shape of a disc, the adhesive layer 5 and the heater 4 form a complete disc. When in use, the heater 4 is first fixed on the insulating layer 3, and then the adhesive is applied to the insulating layer 3, and the adhesive is applied to the insulating layer 3 except the heater 4. Since the thickness of the heater 4 is determined and its thickness can be set as needed, the adhesive is soft, and the ceramic plate 2 and the substrate are pressed together. The distance between the ceramic plate 2 and the substrate is equal to the thickness of the heater 4. At this time, the thickness of the adhesive layer 5 is also equal to the thickness of the heater 4.

[0022] Ceramic plate 2 is an insulating ceramic material with a resistivity higher than 10 16 Ω·cm, which meets the use requirements of electrostatic chuck;

[0023] The heater 4 is made of metal material, and the heater 4 can be made of nickel-chromium alloy or copper;

[0024] The heater 4 is a sheet structure with a thickness of 50-500 μm, which can meet the heating requirements and ensure that the bonding layer 5 can bond the ceramic plate 2 and the substrate together to avoid wasting materials;

[0025] The insulating layer 3 is formed by anodic oxidation or thermal spraying. The insulating layer 3 is formed on the substrate by anodic oxidation or thermal spraying.

[0026] By setting a heating component and setting the heating component between the base 1 and the ceramic plate 2, the heating component is directly attached to the ceramic plate 2, and the heater 4 can be set to a required shape. Compared with the external heater 4, the heating is more uniform and the heat loss is reduced;

[0027] By arranging the heater 4 between the ceramic plate 2 and the base 1, the production cost of the product can be reduced compared to the commonly used method of embedding the heater 4 in the ceramic plate 2;

[0028] By providing the insulating layer 3 on the side of the base 1 facing the ceramic plate 2 , the heater 4 and the base 1 can be separated, thereby preventing the base 1 from being connected to the heater 4 .

[0029] 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. An electrostatic chuck, characterized in that: It includes a base and a ceramic plate, wherein the ceramic plate is provided with an electrode, the base is connected to the ceramic plate by an adhesive layer, an insulating layer is provided on the side of the base facing the ceramic plate, a heating component is provided between the base and the ceramic plate, the heating component includes a heater, the heater is arranged between the base and the ceramic plate, the adhesive layer is provided with a hollow that cooperates with the heater, and the thickness of the heater is equal to the thickness of the adhesive layer.

2. An electrostatic chuck according to claim 1, characterized in that: The ceramic plate is made of insulating ceramic material with a resistivity higher than 10 16 Ω·cm.

3. An electrostatic chuck according to claim 2, characterized in that: The heater is made of metal material.

4. An electrostatic chuck according to claim 3, characterized in that: The heater has a thickness of 50-500 μm.

5. An electrostatic chuck according to claim 1, characterized in that: The insulating layer is made by anodizing or thermal spraying.

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