Electrostatic chuck member, electrostatic chuck device, and method for manufacturing an electrostatic chuck member

Abstract

The present invention provides an electrostatic chuck member, an electrostatic chuck device, and a method for manufacturing the electrostatic chuck member, which improve the reliability of the connection between the electrode and the power supply terminal. [Solution] An electrostatic chuck member comprising a first substrate and a second substrate stacked in the thickness direction, layered electrodes provided between the first substrate and the second substrate, and a power supply terminal for supplying power to the electrodes, wherein the second substrate is provided with a through hole that penetrates in the thickness direction and into which the power supply terminal is inserted, and the electrodes have an intrusion portion located between the inner circumferential surface of the through hole and the outer circumferential surface of the power supply terminal.

Description

Technical Field

[0001] The present invention relates to an electrostatic chuck member, an electrostatic chuck device, and a method for manufacturing an electrostatic chuck member.

Background Art

[0002] In a semiconductor manufacturing process, a plate-like sample such as a silicon wafer is fixed to an electrostatic chuck member by electrostatic adsorption and subjected to a predetermined treatment. Inside the electrostatic chuck member, electrodes such as an electrostatic adsorption electrode for electrostatically adsorbing the plate-like sample and a heater electrode for suppressing temperature unevenness of the plate-like sample are provided (see, for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] A power supply terminal is connected to the electrode. Conventionally, for example, in a molded electrostatic chuck member, a hole reaching the electrode is formed, and the power supply terminal is inserted into the hole and connected by contacting the electrode. However, in this case, it is difficult to control the depth of the hole. If the hole is too deep, the electrode may be damaged, and if the hole is too shallow, the connection resistance between the electrode and the power supply terminal may increase.

[0005] In view of such circumstances, the present invention has been made, and one of the objectives is to provide an electrostatic chuck member, an electrostatic chuck device, and a method for manufacturing an electrostatic chuck member with improved reliability of the connection between the electrode and the power supply terminal.

Means for Solving the Problems

[0006] To solve the above problems, one aspect of the present invention includes the following aspects.

[0007] [1] A first substrate and a second substrate stacked in the thickness direction, A layered electrode provided between the first substrate and the second substrate, The system includes a power supply terminal that supplies power to the electrode, The second substrate is provided with a through hole that penetrates in the thickness direction and into which the power supply terminal is inserted. The electrode is an electrostatic chuck member having an intrusion portion located between the inner circumferential surface of the through hole and the outer circumferential surface of the power supply terminal. [2] The electrostatic chuck member according to [1], wherein the dimension of the penetration portion in the thickness direction is greater than the thickness dimension of the electrode disposed between the first substrate and the second substrate. [3] The electrode is a strip-shaped heater electrode that forms a predetermined pattern when viewed from the thickness direction, An insulating portion is provided between adjacent electrodes between the first substrate and the second substrate. In the thickness direction, the first substrate side is referred to as the first side, and the second substrate side as the second side. The electrostatic chuck member according to [1] or [2], wherein the first width dimension of the first end of the electrode is greater than the second width dimension of the second end of the electrode. [4] The electrostatic chuck member according to [3], wherein the difference between the first width dimension and the second width dimension is greater than or equal to the thickness dimension of the electrode disposed between the first substrate and the second substrate. [5] The electrostatic chuck member according to [3] or [4], wherein the third width dimension of the first end of the insulating portion is smaller than the fourth width dimension of the second end of the insulating portion. [6] The electrostatic chuck member according to [5], wherein the ratio of the difference between the first width dimension and the second width dimension to the difference between the third width dimension and the fourth width dimension is 0.7 or more and 1.3 or less. [7] The electrostatic chuck member according to [5] or [6], wherein the side surface of the electrode and the side surface of the insulating portion face each other with a gap in between. [8] The electrostatic chuck member according to [7], wherein the width dimension of the gap is greater than or equal to the thickness dimension of the electrode disposed between the first substrate and the second substrate, and less than or equal to the fourth width dimension. [9] The electrostatic chuck member according to any one of [5] to [8], wherein the resistivity of the material constituting the insulating portion is greater than the resistivity of the materials constituting the first substrate and the second substrate.

[10] An electrostatic chuck member as described in any one of items [1] to [9], An electrostatic chuck device comprising a base that cools the electrostatic chuck member and adjusts the temperature of the electrostatic chuck member.

[11] A first coating step of applying electrode paste in a strip shape to the first coated surface of the first substrate, A through-hole formation step in which through holes are formed in the second substrate, A lamination step in which the first coated surface is facing the second substrate, the first substrate is placed on top of the second substrate, and the electrode paste is exposed through the through hole, An insertion step of inserting the electrode terminal into the through hole and bringing it into contact with the electrode paste, The process includes a sintering step of sintering the electrode paste, The through-hole formation step is performed before the lamination step. The insertion step is performed after the lamination step. A method for manufacturing an electrostatic chuck component.

[12] A method for manufacturing an electrostatic chuck member according to

[11] , comprising a drying step performed after the first coating step and before the lamination step, wherein the electrode paste is dried and the electrode paste shrinks so that its width decreases as it moves away from the first coating surface.

[13] A second coating step is performed before the drying step and involves applying an insulating paste to the second coated surface of the second substrate, The drying step dries the insulating paste together with the electrode paste, and causes the insulating paste to shrink so that its width decreases as it moves away from the second coating surface. The sintering process is the process of sintering the paste for the insulating portion together with the paste for the electrode, and is the method for manufacturing the electrostatic chuck member described in

[12] .

Advantages of the Invention

[0008] According to the present invention, it is possible to provide an electrostatic chuck member, an electrostatic chuck device, and a method for manufacturing an electrostatic chuck member, which enhance the reliability of the connection between the electrode and the power supply terminal.

Brief Description of the Drawings

[0009] [Figure 1] FIG. 1 is a schematic cross-sectional view showing an electrostatic chuck device and an electrostatic chuck member according to an embodiment. [Figure 2] FIG. 2 is an enlarged cross-sectional view of an electrostatic chuck member according to an embodiment. [Figure 3] FIG. 3 is a flowchart showing a method for manufacturing an electrostatic chuck member according to an embodiment. [Figure 4] FIG. 4 is a schematic view showing a manufacturing process of an electrostatic chuck member according to an embodiment. [Figure 5] FIG. 5 is a schematic view showing a manufacturing process of an electrostatic chuck member according to an embodiment. [Figure 6] FIG. 6 is a captured image of a cross-section of a heater electrode and an insulating portion according to an embodiment. [Figure 7] FIG. 7 is a captured image of a cross-section of a heater electrode and a second power supply terminal according to an embodiment.

Embodiments for Carrying Out the Invention

[0010] Hereinafter, the electrostatic chuck member and the electrostatic chuck device according to the present embodiment will be described with reference to the drawings. In all the following drawings, for ease of viewing, the dimensions, ratios, etc. of each component are appropriately different.

[0011] FIG. 1 is a schematic cross-sectional view showing an electrostatic chuck device 1 and an electrostatic chuck member 2. The electrostatic chuck device 1 comprises an electrostatic chuck member 2 on which a mounting surface 2s for mounting a wafer (plate-shaped sample) W is provided, a base 3 that supports the electrostatic chuck member 2 from the opposite side of the mounting surface 2s, a plurality of first power supply terminals 16A, and a plurality of second power supply terminals 16B. A focus ring (not shown) surrounding the wafer W may be arranged on the outer periphery of the upper surface of the electrostatic chuck member 2.

[0012] Furthermore, the Z-axis is shown in each figure. In this specification, the Z-axis indicates the thickness direction of the first ceramic plate (first substrate) 11 and the second ceramic plate (second substrate) 12 (the thickness direction of the electrostatic chuck member 2), which will be described later. The Z-axis is assumed to extend in the vertical direction, and the direction in which the arrow of the Z-axis points is considered the upper side (first side), and the opposite side is considered the lower side (second side), as each part of the electrostatic chuck device 1 is described accordingly. In this specification, "plan view" means viewing the object from above in the Z-axis direction.

[0013] <Electrostatic Chuck Components> The electrostatic chuck member 2 is disc-shaped. The electrostatic chuck member 2 includes a first ceramic plate 11, a second ceramic plate 12, a heater electrode 21, and an insulating portion 22. The first ceramic plate 11 corresponds to the "first substrate" in the present invention, and the second ceramic plate 12 corresponds to the "second substrate" in the present invention. The first ceramic plate 11 and the second ceramic plate 12 are stacked in the thickness direction. The heater electrode 21 and the insulating portion 22 are provided between the first ceramic plate 11 and the second ceramic plate 12.

[0014] (First ceramic plate) The first ceramic plate 11 is circular in shape when viewed from above. The upper surface of the first ceramic plate 11 is the mounting surface 2s of the electrostatic chuck member 2.

[0015] An electrostatic adsorption electrode 13 is provided inside the first ceramic plate 11. The first ceramic plate 11 has a mounting surface 2s facing upward and a first opposing surface 11f facing downward. For example, a plurality of protrusions (not shown) are formed on the mounting surface 2s at predetermined intervals. The mounting surface 2s supports the wafer W with the tips of the plurality of protrusions. The first opposing surface 11f faces the second ceramic plate 12.

[0016] The first ceramic plate 11 has a first plate portion 11a, a second plate portion 11b, a third plate portion 11c, a first bonding layer 11d, and a second bonding layer 11e. The first plate portion 11a, the second plate portion 11b, and the third plate portion 11c are plate-shaped with the Z-axis direction as the thickness direction. The first plate portion 11a, the second plate portion 11b, and the third plate portion 11c are stacked in this order from top to bottom in the thickness direction.

[0017] A first bonding layer 11d and an electrostatic adsorption electrode 13 are arranged between the first plate portion 11a and the second plate portion 11b. The first bonding layer 11d is provided so as to surround the electrostatic adsorption electrode 13. The first bonding layer 11d bonds the first plate portion 11a and the second plate portion 11b. The electrostatic adsorption electrode 13 extends in layers along a plane perpendicular to the thickness direction (Z-axis direction) of the first ceramic plate 11. As a result, the electrostatic adsorption electrode 13 is embedded inside the first ceramic plate 11.

[0018] A second bonding layer 11e is placed between the second plate portion 11b and the third plate portion 11c. The second bonding layer 11e bonds the second plate portion 11b and the third plate portion 11c. A bias electrode surrounded by the second bonding layer 11e may also be placed between the second plate portion 11b and the third plate portion 11c.

[0019] The second plate portion 11b and the third plate portion 11c are provided with through holes 11k that penetrate in the thickness direction. The through holes 11k are circular in plan view. The first power supply terminal 16A is inserted into the through holes 11k.

[0020] The first ceramic plate 11 is formed by applying unsintered pastes, which constitute the electrostatic adsorption electrode 13, the first bonding layer 11d, and the second bonding layer 11e, to the first plate portion 11a, the second plate portion 11b, and the third plate portion 11c, which are sintered bodies formed by pre-sintering, to the layers in the thickness direction, stacking them, and then hot-pressing them under high temperature and high pressure to integrate them.

[0021] The first plate portion 11a, the second plate portion 11b, the third plate portion 11c, the first bonding layer 11d, and the second bonding layer 11e constituting the first ceramic plate 11 are made of a ceramic material. Suitable ceramic materials for the first ceramic plate 11 include, for example, an aluminum oxide (Al2O3) sintered body, an aluminum nitride (AlN) sintered body, and an aluminum oxide (Al2O3)-silicon carbide (SiC) composite sintered body. In this embodiment, the first plate portion 11a, the second plate portion 11b, the third plate portion 11c, the first bonding layer 11d, and the second bonding layer 11e are made of materials of the same composition. However, the first plate portion 11a, the second plate portion 11b, the third plate portion 11c, the first bonding layer 11d, and the second bonding layer 11e may be made of different materials.

[0022] The electrostatic adsorption electrode 13 is a composite of an insulating material and a conductive material. The insulating material included in the electrostatic adsorption electrode 13 is not particularly limited, but it is preferably at least one selected from the group consisting of Al2O3, AlN, silicon nitride (Si3N4), yttrium(III) oxide (Y2O3), yttrium aluminum garnet (YAG), and SmAlO3.

[0023] A cylindrical first power supply terminal 16A is connected to the electrostatic adsorption electrode 13. The first power supply terminal 16A applies a voltage to the electrostatic adsorption electrode 13. When a voltage is applied, the electrostatic adsorption electrode 13 generates an electrostatic adsorption force that holds the wafer W to the mounting surface 2s. The first power supply terminal 16A penetrates the second plate portion 11b, the third plate portion 11c, the second ceramic plate 12, and the base 3. A cylindrical insulator 18 for insulation is attached to a part of the outer surface of the first power supply terminal 16A. The insulator 18 insulates the first power supply terminal 16A from the base 3.

[0024] (Second ceramic plate) The second ceramic plate 12 is circular in shape when viewed from above. The second ceramic plate 12 has a second opposing surface 12f that faces upward. The second opposing surface 12f faces the first opposing surface 11f of the first ceramic plate 11 in the vertical direction.

[0025] The second ceramic plate 12 is provided with through holes 12d and 12h that penetrate in the thickness direction. The through holes 12d and 12h are circular in plan view. The first power supply terminal 16A is inserted into the through hole 12d. The second power supply terminal 16B is inserted into the through hole 12h.

[0026] The second ceramic plate 12 is made of a ceramic material. Suitable ceramic materials for the second ceramic plate 12 include, for example, an Al2O3 sintered body, an AlN sintered body, and an Al2O3-SiC composite sintered body. In this embodiment, the second ceramic plate 12 is made of the same material as the first ceramic plate 11. However, the second ceramic plate 12 may be made of a different material than the first ceramic plate 11. Furthermore, the second ceramic plate 12 is made from a single sintered body. However, the second ceramic plate 12 may be made by laminating and joining multiple sintered bodies in the thickness direction. In this case, the multiple sintered bodies may be made of different ceramic materials.

[0027] (Heater electrode, insulating part) The heater electrode 21 and the insulating portion 22 are located between the first ceramic plate 11 and the second ceramic plate 12. Both the heater electrode 21 and the insulating portion 22 are layered. The thickness direction of the heater electrode 21 coincides with the thickness direction of the first ceramic plate 11 and the second ceramic plate 12.

[0028] The heater electrode 21 is strip-shaped and forms a predetermined pattern. Cylindrical second power supply terminals 16B are connected to both ends of the heater electrode 21 in the longitudinal direction. The second power supply terminals 16B supply current to the heater electrode 21. That is, the second power supply terminals 16B supply power to the heater electrode 21. The second power supply terminals 16B are connected to the surface facing downwards of the heater electrode 21 and extend downwards from the heater electrode 21. The second power supply terminals 16B penetrate the second ceramic plate 12 and the base 3. A cylindrical insulator 18 is attached to a part of the outer circumferential surface of the second power supply terminal 16B. The insulator 18 insulates the second power supply terminal 16B from the base 3.

[0029] The insulating portion 22 is provided in a shape complementary to the heater electrode 21. The insulating portion 22 is located between a part of the strip-shaped heater electrode 21 and another part adjacent to that part, and insulates them from each other. Furthermore, the insulating portion 22 joins and integrates the first ceramic plate 11 and the second ceramic plate 12 around the heater electrode 21.

[0030] In this embodiment, it is preferable that the volume resistivity of the material constituting the insulating portion 22 is greater than the volume resistivity of the materials constituting the first ceramic plate 11 and the second ceramic plate 12. By making the volume resistivity of the insulating portion 22 greater than the volume resistivity of the first ceramic plate 11 and the second ceramic plate 12, the insulation between the heater electrodes 21 can be sufficiently improved. For example, the above-described relationship of volume resistivity can be satisfied when the insulating portion 22 is made of Al2O3 and the first ceramic plate 11 and the second ceramic plate 12 are made of Al2O3-SiC composite sintered body. The insulating portion 22 may be made of the same insulating material as the material constituting the first ceramic plate 11 and the second ceramic plate 12, for example.

[0031] Furthermore, if the first ceramic plate 11 and the second ceramic plate 12 are each composed of multiple components, the volume resistivity of the insulating portion 22 should be greater than the volume resistivity of the components that make up the first opposing surface 11f and the second opposing surface 12f.

[0032] The heater electrode 21 and the insulating part 22 will be described in detail later.

[0033] <Base> The base 3 is a disc-shaped member in plan view and supports the electrostatic chuck member 2 from below. A flow path 31 for circulating a refrigerant is provided inside the base 3. The refrigerant flowing through the flow path 31 can be water, He gas, N2 gas, etc. The refrigerant in the flow path 31 cools the entire base 3 and also cools the electrostatic chuck member 2 that is in contact with the upper surface of the base 3, thereby adjusting the temperature of the electrostatic chuck member 2.

[0034] Base 3 is connected to an external high-frequency power supply via a matching circuit (not shown) and also serves as an internal electrode for plasma generation.

[0035] (Other components) The electrostatic chuck device 1 is provided with a gas flow path 19. The gas flow path 19 has a first gas hole 19a, a second gas hole 19b, and a connecting passage 19c. The first gas hole 19a and the second gas hole 19b communicate with each other via the connecting passage 19c, and together they constitute the gas flow path 19.

[0036] The first gas hole 19a extends downward from the communication passage 19c and connects to the heat transfer gas introduction section (not shown) at the lower end of the base 3. An insulator 18 is provided around the portion of the first gas hole 19a that passes through the base 3.

[0037] The second gas hole 19b extends upward from the connecting passage 19c and opens onto the mounting surface 2s.

[0038] The connecting passage 19c is located inside the electrostatic chuck member 2 and extends along the planar direction of the mounting surface 2s. In Figure 1, the connecting passage 19c is provided in the second bonding layer 11e described above.

[0039] A heat transfer gas flows through the gas channel 19. The heat transfer gas is a cooling gas, such as helium (He). The heat transfer gas is supplied to the mounting surface 2s via the gas channel 19 to cool the wafer W mounted on the mounting surface 2s.

[0040] (Connection structure between heater electrode and second power supply terminal) Figure 2 is an enlarged cross-sectional view of the electrostatic chuck member 2, and is a cross-sectional view perpendicular to the direction in which the heater electrode 21 extends.

[0041] As shown in Figure 2, a second power supply terminal 16B is inserted into a through hole 12h provided in the second ceramic plate 12. A first chamfered portion 16k is formed on the upper end of the outer circumferential surface of the second power supply terminal 16B. A second chamfered portion 12k is also formed on the upper end of the inner circumferential surface of the through hole 12h. The area of ​​the outer circumferential surface of the second power supply terminal 16B below the first chamfered portion 16k is in contact with the area of ​​the inner circumferential surface of the through hole 12h below the second chamfered portion 12k.

[0042] In this embodiment, the first chamfered portion 16k is naturally formed during the molding of the second power supply terminal 16B and is sufficiently small in size. However, the first chamfered portion 16k may also be formed by chamfering the corner portion of the second power supply terminal 16B. Similarly, the second chamfered portion 12k is naturally formed during the machining of the through hole 12h and is sufficiently small in size. However, the second chamfered portion 12k may also be formed by chamfering the opening of the through hole 12h.

[0043] The first chamfered portion 16k and the second chamfered portion 12k face each other in the radial direction with a gap in between. A portion of the heater electrode 21 penetrates into the gap between the first chamfered portion 16k and the second chamfered portion 12k. In the following description, the portion of the heater electrode 21 that penetrates into the gap between the first chamfered portion 16k and the second chamfered portion 12k will be referred to as the penetration portion 21p. That is, the heater electrode 21 has a penetration portion 21p located between the inner circumferential surface of the through hole 12h and the outer circumferential surface of the second power supply terminal 16B. The penetration portion 21p penetrates into the second opposing surface 12f of the second ceramic plate 12 to a depth of D. In this embodiment, the penetration portion 21p is an annular shape surrounding the second power supply terminal 16B. The penetration portion 21p contacts and is joined to the inner circumferential surface of the through hole 12h. Similarly, the penetration portion 21p is contact-joined to the outer circumferential surface of the second power supply terminal 16B.

[0044] According to this embodiment, the intrusion portion 21p surrounds and contacts the outer circumferential surface of the second power supply terminal 16B, thereby ensuring a large contact area between the heater electrode 21 and the second power supply terminal 16B. This reduces the connection resistance between the heater electrode 21 and the second power supply terminal 16B. Furthermore, by positioning the intrusion portion 21p between the outer circumferential surface of the second power supply terminal 16B and the inner circumferential surface of the through hole 12h and joining them, the second power supply terminal 16B can be firmly fixed to the inner circumferential surface of the through hole 12h, thereby preventing the second power supply terminal 16B from detaching from the through hole 12h. In other words, according to this embodiment, the reliability of the connection between the heater electrode 21 and the second power supply terminal 16B can be increased.

[0045] In this embodiment, the depth D of the intrusion portion 21p is greater than the thickness H of the heater electrode 21, which is positioned between the first ceramic plate 11 and the second ceramic plate 12. According to this embodiment, by making the depth D of the intrusion portion 21p greater than the thickness H of the heater electrode 21, the contact area with the second power supply terminal 16B at the intrusion portion 21p can be sufficiently widened, and the connection resistance between the heater electrode 21 and the second power supply terminal 16B can be sufficiently reduced. The depth D of the intrusion portion 21p is the dimension in the thickness direction of the intrusion portion 21p, and can be deeper than the chamfer dimensions of the first chamfer portion 16k and the second chamfer portion 12k.

[0046] To ensure a sufficiently deep penetration portion 21p, it is preferable to make the chamfer dimensions of the first chamfer portion 16k and the second chamfer portion 12k larger than the thickness dimension H of the heater electrode 21. Also, to ensure a sufficiently deep penetration portion 21p, for example, the diameter of the through hole 12h may be made 100 μm or more larger than the diameter of the second power supply terminal 16B. In this case, the gap between the outer surface of the second power supply terminal 16B and the inner surface of the through hole 12h can be widened, allowing the penetration portion 21p to penetrate deeply into this gap. However, if this chamfer dimension is made too large, a gap will be created inside the ceramic plate, so it is desirable to set it to an upper limit of about 1000 μm.

[0047] In this specification, the structure of the connection portion between the heater electrode 21 and the second power supply terminal 16B has been described. However, a similar structure can also be used for the connection portion between the electrostatic adsorption electrode 13 and the first power supply terminal 16A, as shown in Figure 1. That is, in this embodiment, the electrostatic adsorption electrode 13 may have an intrusion portion located between the inner circumferential surface of the through hole 11k of the second plate portion 11b and the outer circumferential surface of the first power supply terminal 16A. In this case, a wider contact area between the electrostatic adsorption electrode 13 and the first power supply terminal 16A can be secured, thereby improving the reliability of the connection. The type of electrode having an intrusion portion is not limited to the heater electrode 21 or the electrostatic adsorption electrode 13, but may be other electrodes such as an RF (Radio Frequency) electrode.

[0048] (Heater electrodes and insulating parts) As shown in Figure 2, an insulating portion 22 is placed between adjacent heater electrodes 21 to suppress electrical conductivity between the heater electrodes 21. Furthermore, a gap 29 is provided between the insulating portion 22 and the heater electrodes 21. In addition, the side surface 21a of the heater electrode 21 and the side surface 22a of the insulating portion 22 are inclined.

[0049] The heater electrode 21 gradually decreases in width from the upper side (+Z) to the lower side (-Z). Here, the width of the upper end (first end) of the heater electrode 21 is defined as the first width dimension L1, and the width of the lower end (second end) is defined as the second width dimension L2. In this embodiment, the first width dimension L1 is larger than the second width dimension L2. L1>L2

[0050] In this specification, the width dimensions of the heater electrode 21, the insulating portion 22, and the gap 29 refer to the dimensions of the heater electrode 21 in a direction perpendicular to both the thickness direction and the direction in which the heater electrode 21 extends.

[0051] According to this embodiment, the contact area between the heater electrode 21 and the first ceramic plate 11 can be widened while suppressing the cross-sectional area of ​​the heater electrode 21. The amount of heat generated by the heater electrode 21 can be increased by reducing the cross-sectional area of ​​the heater electrode 21. According to this embodiment, it is possible to efficiently transfer the heat generated from the heater electrode 21 to the first ceramic plate 11 while increasing the amount of heat generated by the heater electrode 21. As a result, it becomes easier to quickly control the temperature of the mounting surface 2s with the heater electrode 21, and it is possible to immediately suppress temperature unevenness on the mounting surface 2s.

[0052] Furthermore, as will be described later, the heater electrode 21 in this embodiment is formed by drying and sintering an electrode paste. The electrode paste is dried and sintered after application. The electrode paste shrinks during drying, and its width decreases as it moves away from the application surface in the thickness direction. Therefore, the heater electrode 21 after sintering also decreases in width from one side to the other in the thickness direction. According to this embodiment, by making the side with the larger width dimension of the heater electrode 21 the upper side, the contact area between the heater electrode 21 and the first ceramic plate 11 can be made larger than the contact area between the heater electrode 21 and the second ceramic plate 12. This makes it easier to transfer heat from the heater electrode 21 to the mounting surface 2s of the first ceramic plate 11.

[0053] In recent electrostatic chuck components, heater electrodes 21 are densely arranged inside the electrostatic chuck component 2. For example, in an electrostatic chuck component 2 with a diameter of 30 cm, the total length of the heater electrodes 21 reaches approximately 900 cm. If the difference between the first width dimension L1 and the second width dimension L2 (L1-L2) is approximately 100 μm, the contact area between the heater electrodes 21 and the first ceramic plate 11 is 9 cm larger than the contact area between the heater electrodes 21 and the second ceramic plate 12. 2 The contact area becomes significantly larger. Thus, even a small difference in contact length of about 100 μm in one cross-section of the heater electrode 21 results in a sufficiently large contact area across the entire heater electrode 21. According to this embodiment, the heater electrode 21 as a whole has a significant impact on the temperature controllability of the mounting surface 2s, and the temperature controllability of the mounting surface 2s can be significantly improved.

[0054] In this embodiment, it is preferable that the difference between the first width dimension L1 and the second width dimension L2 (L1-L2) is greater than or equal to the thickness dimension H of the heater electrode 21 placed between the first ceramic plate 11 and the second ceramic plate 12. L1-L2≧H In this case, the contact area between the heater electrode 21 and the first ceramic plate 11 can be made significantly larger than the contact area between the heater electrode 21 and the second ceramic plate 12. This makes it possible to efficiently transfer heat from the heater electrode 21 to the first ceramic plate 11 while suppressing the cross-sectional area of ​​the heater electrode 21.

[0055] Furthermore, the difference (L1-L2) between the first width dimension L1 and the second width dimension L2 is preferably between 10 μm and 1000 μm. By setting the difference (L1-L2) to 10 μm or more, it is possible to suppress the cross-sectional area of ​​the heater electrode 21 while making it easier to transfer heat to the first ceramic plate 11, and effectively suppressing temperature unevenness on the mounting surface 2s. On the other hand, if the difference (L1-L2) exceeds 1000 μm, it becomes difficult to secure a contact area between the heater electrode 21 and the second ceramic plate 12. The first ceramic plate 11 is supported by the second ceramic plate 12 via the heater electrode 21 and the insulating part 22. Therefore, if the contact area between the heater electrode 21 and the second ceramic plate 12 becomes too small, the first ceramic plate 11 may not be sufficiently supported, and there is a risk that the first ceramic plate 11 may bend. According to this embodiment, by making the difference (L1-L2) 1000 μm or less, the deflection of the first ceramic plate 11 can be suppressed.

[0056] As shown in Figure 2, the width of the insulating portion 22 gradually decreases from the bottom (-Z) to the top (+Z). Here, the width of the upper end (first end) of the insulating portion 22 is defined as the third width dimension L3, and the width of the lower end (second end) is defined as the fourth width dimension L4. In this embodiment, the third width dimension L3 is smaller than the fourth width dimension L4. L3 <L4

[0057] Here, the width dimension of the upper end of the insulating portion 22 refers to the width dimension of the insulating portion 22 along the extension line of the upper end surface of the heater electrode 21. Similarly, the width dimension of the lower end of the insulating portion 22 refers to the width dimension of the insulating portion 22 along the extension line of the lower end surface of the heater electrode 21.

[0058] According to this embodiment, the side surface 22a of the insulating portion 22 can be inclined in a direction substantially parallel to the side surface 21a of the opposing heater electrode 21. This allows the heater electrode 21 and the insulating portion 22 to be brought closer together, making it possible to precisely arrange the heater electrode 21 and the insulating portion 22. By precisely arranging the heater electrode 21 and the insulating portion 22, it becomes easier to reduce temperature unevenness on the mounting surface 2s by the heater electrode 21.

[0059] The insulating paste is dried and sintered after application. The insulating paste shrinks during drying, and its width decreases as it moves away from the application surface in the thickness direction. Therefore, the insulating part 22 after sintering also decreases in width from one side to the other in the thickness direction. According to this embodiment, by making the side of the insulating part 22 with a larger width the lower side, which is the side of the heater electrode 21 with a smaller width, the side surface 22a of the insulating part 22 can be positioned away from the side surface 21a of the heater electrode 21 throughout its entire thickness direction. This makes it possible to precisely position the heater electrode 21 and the insulating part 22 while ensuring sufficient distance between them.

[0060] The difference between the third width dimension L3 and the fourth width dimension L4 (L4-L3) is more preferably between 10 μm and 1000 μm, similar to the difference between the first width dimension L1 and the second width dimension L2 (L1-L2). This suppresses conductivity between adjacent heater electrodes 21 while suppressing the deflection of the first ceramic plate 11. Furthermore, by setting the difference between the third width dimension L3 and the fourth width dimension L4 (L4-L3) and the difference between the first width dimension L1 and the second width dimension L2 (L1-L2) to approximately the same value, it becomes possible to further increase the installation density of the heater electrodes 21.

[0061] In this embodiment, the ratio of the difference between the first width dimension L1 and the second width dimension L2 (L1-L2) to the difference between the third width dimension L3 and the fourth width dimension L4 (L4-L3) is preferably 0.7 or more and 1.3 or less. 0.7 ≤ (L1-L2) / (L4-L3) ≤ 1.3 When this ratio ((L1-L2) / (L4-L3)) is 1, the heater electrodes 21 and the insulating part 22 can be arranged most densely. Furthermore, if the above ratio is in the range of 0.7 to 1.3, the heater electrodes 21 and the insulating part 22 can be arranged sufficiently densely, and the temperature unevenness of the mounting surface 2s can be sufficiently reduced.

[0062] In this embodiment, the side surface 21a of the heater electrode 21 and the side surface 22a of the insulating portion 22 face each other with a gap 29 in between. According to this embodiment, an air layer can be provided between the heater electrode 21 and the insulating portion 22, thereby improving the insulation performance between the heater electrodes 21. Furthermore, it becomes easier to suppress the mixing of these components during the molding of the heater electrode 21 and the insulating portion 22, making it easier to ensure the insulation performance of the insulating portion 22.

[0063] The width dimension of the gap 29 is defined as the fifth width dimension L5. Preferably, the fifth width dimension L5 is greater than or equal to the thickness dimension H of the heater electrode 21, which is placed between the first ceramic plate 11 and the second ceramic plate 12, and less than or equal to the fourth width dimension L4. H ≤ L5 ≤ L4 By making the fifth width dimension L5 greater than or equal to the thickness dimension H of the heater electrode 21, the heater electrode 21 and the insulating part 22 can be reliably separated by the gap 29, and the insulation performance between the heater electrodes 21 can be sufficiently improved. On the other hand, if the fifth width dimension L5 is made too wide, the distance between the heater electrodes 21 becomes too wide, and the temperature controllability of the mounting surface 2s decreases. Therefore, by making the fifth width dimension L5 less than or equal to the fourth width dimension L4, the heater electrodes 21 can be arranged more densely, making it easier to reduce temperature unevenness on the mounting surface 2s.

[0064] Note that the fifth width dimension L5 is not necessarily constant throughout the entire thickness direction of the gap 29. In this embodiment, the fifth width dimension L5 is sufficient to be greater than or equal to the thickness dimension H of the heater electrode 21 and less than or equal to the fourth width dimension L4 at any position in the thickness direction.

[0065] (Method for manufacturing electrostatic chuck members) The electrostatic chuck member 2 of this embodiment is manufactured as follows, as an example. Figure 3 is a flowchart showing the manufacturing method of the electrostatic chuck member 2 of this embodiment. The manufacturing method of the electrostatic chuck member 2 includes a through-hole forming step S10, a first coating step S20, a second coating step S30, a drying step S40, a lamination step S50, an insertion step S60, and a sintering step S70.

[0066] Figure 4 is a schematic diagram showing the manufacturing process of the electrostatic chuck member 2 of this embodiment up to the lamination process S50. The through-hole formation process S10 is a process of forming a through-hole 12h in the second ceramic plate 12. In this embodiment, the through-hole formation process S10 is performed before the first coating process S20, the second coating process S30, and the drying process S40. However, the through-hole formation process S10 may be performed at any time before the lamination process S50.

[0067] In the through-hole formation step S10 of this embodiment, the through-hole 12h is formed, for example, by machining the second ceramic plate 12 with a diamond drill. Alternatively, the through-hole 12h may be formed by laser processing, electrical discharge machining, ultrasonic processing, or the like.

[0068] The first coating step S20 is a step of applying electrode paste 211 in a strip shape to the first opposing surface (first coating surface) 11f of the first ceramic plate 11. In the first coating step S20 of this embodiment, a printing method such as screen printing is used to form a pattern of electrode paste 211 on the first opposing surface 11f. This pattern has a shape that corresponds to the pattern shape of the heater electrode 21 in a plan view.

[0069] The electrode paste 211 can be made from any known material as long as it can form the heater electrode 21. The electrode paste 211 may, for example, contain a conductive material, ceramic powder, a binder, and a solvent. Examples of conductive materials include tungsten, tungsten carbide, platinum, silver, palladium, nickel, and molybdenum. Examples of ceramic powders include powder made from the same type of ceramic material as the materials constituting the first ceramic plate 11 and the second ceramic plate 12. Examples of binders include ethylcellulose, polymethyl methacrylate, and polyvinyl butyral. Examples of solvents include terpineol.

[0070] The second coating step S30 is a step of applying insulating paste 221 to the second opposing surface (second coating surface) 12f of the second ceramic plate 12. In the second coating step S30 of this embodiment, a printing method such as screen printing is used to form a pattern of insulating paste 221 on the second opposing surface 12f. The electrode paste 211 and the insulating paste 221 are provided complementaryly between the first ceramic plate 11 and the second ceramic plate 12. In addition, the insulating paste 221 is provided in a position that avoids the opening of the through hole 12h.

[0071] The insulating paste 221 may, for example, contain insulating ceramic powder, a binder, and a solvent. Examples of insulating ceramic powder include the powder of the material described above as the material for the insulating part 22. The binder and solvent of the insulating paste 221 can be the same materials used in the electrode paste 211 described above.

[0072] The first coating step S20 and the second coating step S30 may be performed at any time before the drying step S40. For example, the first coating step S20 and the second coating step S30 may be performed before the through-hole forming step S10, or the second coating step S30 may be performed before the first coating step S20.

[0073] Drying step S40 is a step in which the electrode paste 211 is dried to form the first precursor 212 of the heater electrode 21, and the insulating paste 221 is dried to form the second precursor 222 of the insulating part 22.

[0074] The cross-sectional shape of the first precursor 212 formed in drying step S40 is a roughly trapezoidal shape, with the width decreasing towards the bottom. On the other hand, the cross-sectional shape of the second precursor 222 formed in drying step S40 is a roughly trapezoidal shape, with the width decreasing towards the top. In other words, drying step S40 is a step in which the electrode paste 211 shrinks so that its width decreases as it moves away from the first opposing surface 11f, and the insulating paste 221 shrinks so that its width decreases as it moves away from the second opposing surface 12f.

[0075] The roughly trapezoidal first precursor 212 and second precursor 222 can be formed by drying the paste in a high-temperature environment for a short period of time, for example, by drying it at 90°C for 30 minutes, instead of the usual drying conditions of 30°C for 6 hours.

[0076] Figure 5 is a schematic diagram showing the manufacturing process of the electrostatic chuck member 2 of this embodiment from the lamination process S50 onwards. The lamination process S50 is a process in which the first ceramic plate 11 is stacked on the second ceramic plate 12 with the first opposing surface 11f facing the second ceramic plate 12. In the through-hole formation process S10, the through-hole 12h is formed in a position that overlaps with the electrode paste 211 applied in the first coating process S20. Therefore, by laminating the first ceramic plate 11 and the second ceramic plate 12 in the lamination process S50, the first precursor 212 (i.e., the dried electrode paste 211) is exposed from the through-hole 12h.

[0077] Insertion step S60 is the step of inserting the second power supply terminal 16B into the through hole 12h and bringing it into contact with the first precursor 212 (i.e., the dried electrode paste 211). The end face of the second power supply terminal 16B is pressed against the electrode paste 211. As a result, a portion of the electrode paste 211 penetrates into the gap between the inner surface of the through hole 12h and the outer surface of the second power supply terminal 16B.

[0078] Sintering step S70 is a step in which the first precursor 212 and the second precursor 222 are sintered. In this embodiment, sintering step S70 is a step in which the first ceramic plate 11 and the second ceramic plate 12 are hot-pressed at a temperature of 1400°C to 1900°C in a non-oxidizing atmosphere while being pressurized in the thickness direction at 1 MPa to 50 MPa.

[0079] As shown in Figure 2, through the sintering process S70, the first precursor 212 becomes the heater electrode 21, and the second precursor 222 becomes the insulating part 22. The first ceramic plate 11, the second ceramic plate 12, and the second power supply terminal 16B are joined together by the heater electrode 21 and the insulating part 22, forming a single unit. A portion of the electrode paste 211 penetrates into the gap between the inner surface of the through hole 12h and the outer surface of the second power supply terminal 16B and is sintered, forming an intrusion portion 21p.

[0080] In the manufacturing method of this embodiment, the through-hole formation step S10 is performed before the lamination step S50. In conventional manufacturing methods, the through-hole 12h was formed after the lamination step S50. In this case, it was difficult to adjust the drilling depth so that the tip of the through-hole 12h coincided with one surface of the thin-film heater electrode 21. In this embodiment, by forming the through-hole 12h in the second ceramic plate 12 in advance before performing the lamination step S50, it is not necessary to precisely adjust the depth of the through-hole 12h. Therefore, it is possible to suppress damage to the heater electrode 21 or an increase in the connection resistance between the heater electrode 21 and the second power supply terminal 16B in the through-hole formation step S10, and to manufacture an electrostatic chuck member 2 with improved reliability of the connection between the heater electrode 21 and the second power supply terminal 16B.

[0081] In the manufacturing method of this embodiment, in the first coating step S20, the electrode paste 211 is applied to the first opposing surface 11f of the first ceramic plate 11. Through holes 12h are formed in the second ceramic plate 12. Therefore, when the electrode paste 211 is applied to the second ceramic plate 12, the electrode paste 211 flows into the inner circumferential surface of the through holes 12h, making it impossible to apply the electrode paste 211 with a uniform film thickness. In this embodiment, by applying the electrode paste 211 to the first ceramic plate 11 in which no through holes 12h are formed, an electrode paste 211 with a uniform film thickness can be formed.

[0082] Furthermore, in order to prevent the electrode paste 211 from flowing into the through hole 12h, it is also possible to apply the electrode paste 211 to the second ceramic plate 12 after inserting the second power supply terminal 16B into the through hole 12h. In this case, even if the second opposing surface 12f is polished with the second power supply terminal 16B inserted, a minute step will remain between the second opposing surface 12f and the second power supply terminal 16B. For this reason, it is difficult to apply the electrode paste 211 uniformly.

[0083] According to the manufacturing method of this embodiment, in the drying step S40, the electrode paste 211 (i.e., the first precursor 212) after drying can be shrunk so that its width decreases as it moves away from the first opposing surface 11f. As a result, the area of ​​the heater electrode 21 after sintering that contacts the first opposing surface 11f can be made larger than the area of ​​the heater electrode 21 that contacts the second opposing surface 12f.

[0084] According to the manufacturing method of this embodiment, the insulating paste 221 is applied to the second opposing surface 12f of the second ceramic plate 12 in the second coating step S30, and then dried in the drying step S40. Therefore, the insulating paste 221 (i.e., the second precursor 222) after drying can be shrunk so that its width decreases as it moves away from the second opposing surface 12f. As a result, after sintering, the side surface 22a of the insulating part 22 can be tilted in the same direction as the side surface 21a of the heater electrode 21, and the insulating part 22 and the heater electrode 21 can be brought closer together and the heater electrode 21 can be densely arranged while securing a gap 29 between the insulating part 22 and the heater electrode 21.

[0085] In the lamination process S50 of this embodiment, the upper and lower ends of the first precursor 212 and the second precursor 222 are compressed and spread in the width direction. If the first precursor 212 and the second precursor 222 are too close together, the first precursor 212 and the second precursor 222, which are spreading in the width direction, may mix with each other, potentially reducing the insulating properties of the insulating portion 22. According to this embodiment, the electrode paste 211 and the insulating portion paste 221 are applied to the opposing surfaces (first opposing surface 11f and second opposing surface 12f) of the ceramic plates that face each other. Therefore, the sides of the first precursor 212 and the second precursor 222 that face each other can be tilted in a direction that is substantially parallel to each other. As a result, the upper end of the first precursor 212 can be positioned away from the upper end of the second precursor 222, and the lower end of the first precursor 212 can be positioned away from the lower end of the second precursor 222. As a result, even if the upper and lower ends of the first precursor 212 and the second precursor 222 spread out in the width direction, mixing of them with each other can be suppressed, and electrical conductivity between adjacent heater electrodes 21 can be suppressed.

[0086] In this embodiment, the insertion step S60 is performed after the lamination step S50. Therefore, in the insertion step S60, the tip surface of the second power supply terminal 16B can be sufficiently pressed against the electrode paste 211, and the remaining gap between the second power supply terminal 16B and the electrode paste 211 can be suppressed. In contrast, if the lamination step S50 is performed with the second power supply terminal 16B inserted into the through hole 12h, there is a risk that a gap will remain between the electrode paste 211 and the second power supply terminal 16B. According to this embodiment, the reliability of the connection between the second power supply terminal 16B and the electrode paste 211 can be improved.

[0087] Figure 6 is a photograph of the cross-section of the heater electrode 21 and the insulating portion 22 in the electrostatic chuck member 2 of this embodiment. As shown in Figure 6, it was confirmed that, according to this embodiment, the side surface 21a of the heater electrode 21 and the side surface 22a of the insulating portion 22 are inclined in a direction that is substantially parallel to each other. Furthermore, according to this embodiment, it was confirmed that the side surface 21a of the heater electrode 21 and the side surface 22a of the insulating portion 22 face each other with a gap 29 in between.

[0088] Figure 7 is a photograph of the cross-section of the heater electrode 21 and the second power supply terminal 16B in the electrostatic chuck member 2 of this embodiment. As shown in Figure 7, according to this embodiment, it was confirmed that the intrusion portion 21p enters the gap between the inner circumferential surface of the through hole 12h and the outer circumferential surface of the second power supply terminal 16B.

[0089] Preferred embodiments of the present invention have been described above with reference to the attached drawings, but the present invention is not limited to these examples. The shapes and combinations of the constituent members shown in the above examples are merely examples, and can be modified in various ways based on design requirements, etc., without departing from the spirit of the present invention.

[0090] For example, in the above-described embodiment, the heater electrode 21 was described in a case where both sides in the width direction are inclined, but the inclination shape of both sides is not limited as long as the first width dimension L1 and the second width dimension L2 satisfy the above-described relationship. Similarly, in the above-described embodiment, the insulating portion 22 was described in a case where both sides in the width direction are inclined, but the inclination shape of both sides is not limited as long as the third width dimension L3 and the fourth width dimension L4 satisfy the above-described relationship. [Explanation of Symbols]

[0091] 1...Electrostatic chuck device, 2...Electrostatic chuck member, 3...Base, 11...First ceramic plate (first substrate), 11f...First opposing surface (first coated surface), 11k, 12d, 12h...Through hole, 12...Second ceramic plate (second substrate), 12f...Second opposing surface (second coated surface), 21p...Intrusion part, 16B...Second power supply terminal (power supply terminal), 21...Heater electrode (electrode), 21a, 22a...side, 22...insulating part, 29...gap, 211...electrode paste, 221...insulating part paste, H...thickness dimension, L1...first width dimension, L2...second width dimension, L3...third width dimension, L4...fourth width dimension, S10...through hole formation process, S20...first coating process, S30...second coating process, S40...drying process, S50...lamination process, S60...insertion process, S70...sintering process

Claims

1. A first substrate and a second substrate stacked in the thickness direction, A layered electrode provided between the first substrate and the second substrate, The system includes a power supply terminal that supplies power to the electrode, The second substrate is provided with a through hole that penetrates in the thickness direction and into which the power supply terminal is inserted. The electrode has an intrusion portion located between the inner circumferential surface of the through hole and the outer circumferential surface of the power supply terminal. Electrostatic chuck component.

2. The dimension of the intrusion portion in the thickness direction is greater than the thickness dimension of the electrode disposed between the first substrate and the second substrate. The electrostatic chuck member according to claim 1.

3. The electrode is a strip-shaped heater electrode that forms a predetermined pattern when viewed from the thickness direction, Between the first substrate and the second substrate, an insulating portion is provided between adjacent electrodes. In the thickness direction, the first substrate side is referred to as the first side, and the second substrate side as the second side. The first width dimension of the first end of the electrode is greater than the second width dimension of the second end of the electrode. The electrostatic chuck member according to claim 1.

4. The difference between the first width dimension and the second width dimension is greater than or equal to the thickness dimension of the electrode placed between the first substrate and the second substrate. The electrostatic chuck member according to claim 3.

5. The third width dimension of the first end of the insulating portion is smaller than the fourth width dimension of the second end of the insulating portion. The electrostatic chuck member according to claim 3.

6. The ratio of the difference between the first width dimension and the second width dimension to the difference between the third width dimension and the fourth width dimension is 0.7 or more and 1.3 or less. The electrostatic chuck member according to claim 5.

7. The side surface of the electrode and the side surface of the insulating part face each other with a gap in between. The electrostatic chuck member according to claim 5.

8. The width dimension of the gap is greater than or equal to the thickness dimension of the electrode disposed between the first substrate and the second substrate, and less than or equal to the fourth width dimension. The electrostatic chuck member according to claim 7.

9. The resistivity of the material constituting the insulating portion is greater than the resistivity of the materials constituting the first substrate and the second substrate. The electrostatic chuck member according to claim 5.

10. An electrostatic chuck member according to any one of claims 1 to 9, The system includes a base that cools the electrostatic chuck member and adjusts the temperature of the electrostatic chuck member, Electrostatic chuck device.

11. A first coating step involves applying an electrode paste in a strip-like manner to the first coated surface of the first substrate, A through-hole formation step in which through holes are formed in the second substrate, A lamination step in which the first coated surface is facing the second substrate, the first substrate is placed on top of the second substrate, and the electrode paste is exposed through the through hole, An insertion step of inserting the electrode terminal into the through hole and bringing it into contact with the electrode paste, The process includes a sintering step of sintering the electrode paste, The through-hole formation step is performed before the lamination step. The insertion step is performed after the lamination step. A method for manufacturing an electrostatic chuck component.

12. A drying step is performed after the first coating step and before the lamination step, and includes drying the electrode paste and shrinking the electrode paste so that its width decreases as it moves away from the first coating surface. A method for manufacturing an electrostatic chuck member according to claim 11.

13. The process includes a second coating step, which is performed before the drying step, and involves applying an insulating paste to the second coated surface of the second substrate. The drying step dries the insulating paste together with the electrode paste, and causes the insulating paste to shrink so that its width decreases as it moves away from the second coating surface. The sintering step is a step of sintering the insulating paste together with the electrode paste. A method for manufacturing an electrostatic chuck member according to claim 12.

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