Support member, electrostatic chuck, heater, and plasma treatment device

Abstract

This support member comprises: a body part; a first electrode; a second electrode; and a connecting part. The body part is made of ceramic and has a support surface for supporting an object to be treated. The first electrode is located inside the body part. The second electrode is physically and electrically connected to a power supply terminal. The connecting part electrically interconnects the first electrode and the second electrode. In the connection part, a plurality of connection layers and a plurality of via conductors are located side by side along the thickness direction of the body part. The plurality of connection layers have substantially the same shape and are located in substantially the same position when viewed from a direction parallel to the thickness direction. The plurality of via conductors are all located in different positions so as not to overlap each other when viewed from a direction parallel to the thickness direction.

Description

Support member, electrostatic chuck, heater, and plasma processing apparatus

[0001] The disclosed embodiments relate to a support member, an electrostatic chuck, a heater, and a plasma processing apparatus.

[0002] In the process of manufacturing semiconductor components, a support member is used to support a workpiece, such as a semiconductor wafer, that is the target of various processes. One known example of such a support member is an electrostatic chuck, which includes a ceramic body, an attraction electrode and an electrode terminal located inside and on the back side of the body, and a connection portion that electrically connects the attraction electrode and the electrode terminal. The connection portion includes via conductors.

[0003] Patent No. 7448060

[0004] The support member of the present disclosure comprises a main body, a first electrode, a second electrode, and a connection portion. The main body is made of ceramic and has a support surface that supports the workpiece. The first electrode is located inside the main body. The second electrode is physically and electrically connected to a power supply terminal. The connection portion electrically connects the first electrode and the second electrode. The connection portion has multiple connection layers and multiple via conductors positioned side by side along the thickness direction of the main body. The multiple connection layers have approximately the same shape and are positioned at approximately the same positions when viewed through in a direction parallel to the thickness direction. The multiple via conductors are all positioned at different positions so as not to overlap each other when viewed through in a direction parallel to the thickness direction.

[0005] FIG. 1 is a cross-sectional view showing an example of the configuration of a support member according to an embodiment. FIG. 2 is a perspective view showing an example of the configuration of a connection portion according to an embodiment. FIG. 3 is a planar perspective view showing an example of the configuration of a connection portion according to an embodiment. FIG. 4 is a planar perspective view showing an example of the configuration of a connection portion according to another embodiment 1. FIG. 5 is a planar perspective view showing an example of the configuration of a connection portion according to another embodiment 2. FIG. 6 is a planar perspective view showing an example of the configuration of a connection portion according to another embodiment 3. FIG. 7 is a perspective view showing an example of the configuration of a connection portion according to another embodiment 4. FIG. 8 is a planar perspective view showing an example of the configuration of a connection portion according to another embodiment 4.

[0006] Hereinafter, with reference to the accompanying drawings, various embodiments of the support member, electrostatic chuck, heater, and plasma processing apparatus disclosed herein will be described. Note that the present disclosure is not limited to the various embodiments described below. Furthermore, various embodiments can be appropriately combined within the scope of the processing content without causing any contradiction. Furthermore, the same components in the various embodiments below will be assigned the same reference numerals, and redundant explanations will be omitted.

[0007] In addition, in the following embodiments, expressions such as "parallel" and "perpendicular" may be used, but these expressions do not necessarily mean "parallel" or "perpendicular" in the strict sense. In other words, the above expressions allow for deviations due to, for example, manufacturing precision, installation precision, etc.

[0008] In addition, in the drawings referred to below, in order to make the explanation easier to understand, an orthogonal coordinate system may be shown in which the X-axis direction, Y-axis direction, and Z-axis direction, which are perpendicular to each other, are defined, and the Z-axis direction is the thickness direction of the main body portion of the support member.

[0009] In the process of manufacturing semiconductor components, a support member is used to support a workpiece, such as a semiconductor wafer, that is the target of various processes. One known example of such a support member is an electrostatic chuck, which includes a ceramic body, an attraction electrode and an electrode terminal located inside and on the back side of the body, and a connection portion that electrically connects the attraction electrode and the electrode terminal. The connection portion includes via conductors.

[0010] In the above-mentioned conventional technology, differences in shrinkage rates during firing tend to occur between the via conductors, which contain a large amount of metal components, and the main body portion, which is made of ceramic, and there is a risk that the via conductors will protrude in the thickness direction from the main body portion after the firing process during manufacturing, resulting in the via conductors being pushed up.

[0011] Therefore, it is desired to realize a support member that can solve the above problems and reduce the protrusion of via conductors.

[0012] <Embodiment> First, the configuration of a support member 1 according to an embodiment will be described with reference to Figures 1 to 3. Figure 1 is a cross-sectional view showing an example of the configuration of a support member 1 according to an embodiment. As shown in Figure 1, the support member 1 according to the embodiment may include a main body 10, a first electrode 20, a second electrode 30, and a connection portion 40. Note that the sizes of these components may be similar to those of, for example, conventionally known support members, electrostatic chucks, heaters, and plasma processing devices.

[0013] The main body 10 may be made of ceramic. The main body 10 may be made by molding a ceramic-containing raw material into a flat plate shape, for example, a substantially circular plate shape. The main body 10 may be made of, for example, aluminum oxide (Al ２ O ３ ), aluminum nitride (AlN), or yttria (Y ２ O ３ ) may be contained as a main component.

[0014] The main body 10 may have, for example, a support surface 10a and a back surface 10b. The support surface 10a may be a surface that supports a workpiece A such as a semiconductor wafer. The back surface 10b may be located on the opposite side of the support surface 10a.

[0015] The first electrode 20 may be located inside the main body 10. For example, the first electrode 20 may be located near the support surface 10a of the main body 10 and parallel to the support surface 10a. Note that in the present disclosure, the first electrode 20 is not limited to being located inside the main body 10, and may be, for example, partially exposed from the support surface 10a of the main body 10.

[0016] When the support member 1 is used as part of an electrostatic chuck or a plasma processing apparatus, the first electrode 20 may be made of a conductor whose main component is a metal such as molybdenum (Mo), platinum (Pt), or tungsten (W).

[0017] Furthermore, when the support member 1 is used as a heater, the first electrode 20 may be made of a heating resistor whose main component is a metal such as tungsten, molybdenum, platinum, or rhenium (Re).

[0018] The second electrode 30 may be positioned so as to be exposed from at least a portion of the main body portion 10. The second electrode 30 may be positioned so as to be exposed at least a portion of the second electrode 30 from the rear surface 10b of the main body portion 10, for example.

[0019] A power supply terminal T may be electrically and physically connected to the exposed portion 30a of the second electrode 30. In an embodiment, a predetermined amount of power may be supplied to the second electrode 30 from an external power source (not shown) via the power supply terminal T. The second electrode 30 may be made of a conductor containing, as a main component, a metal such as molybdenum, platinum, or tungsten.

[0020] The connection portion 40 may be located inside the main body portion 10 and may electrically connect between the first electrode 20 and the second electrode 30. Fig. 2 is a perspective view showing an example of the configuration of the connection portion 40 according to the embodiment. Fig. 3 is a plan view perspective view showing an example of the configuration of the connection portion 40 according to the embodiment.

[0021] 2, the connecting portion 40 according to the embodiment may have a plurality of connecting layers 41 and a plurality of via conductors 42. The connecting layers 41 may be located, for example, parallel to the first electrode 20 (see FIG. 1) and the second electrode 30 (see FIG. 1). The connecting layers 41 may be made of a conductor containing, for example, a metal such as molybdenum, platinum, or tungsten as a main component.

[0022] The via conductor 42 may be located, for example, perpendicular to the connection layer 41. The via conductor 42 may be made of a conductor whose main component is a metal such as molybdenum, platinum, or tungsten.

[0023] In the connection portion 40, the plurality of connection layers 41 and the plurality of via conductors 42 may be arranged side by side along the thickness direction of the main body portion 10 (see FIG. 1 ). For example, in the connection portion 40, the plurality of connection layers 41 and the plurality of via conductors 42 may be arranged alternately along the thickness direction of the main body portion 10.

[0024] Specifically, in an embodiment, via conductor 42a, connection layer 41a, via conductor 42b, connection layer 41b, via conductor 42c, connection layer 41c and via conductor 42d may be positioned in that order from the side closest to the support surface 10a of the main body portion 10 (see Figure 1).

[0025] The via conductor 42a may electrically connect the first electrode 20 and the connection layer 41a. The via conductor 42b may electrically connect the connection layer 41a and the connection layer 41b. The via conductor 42c may electrically connect the connection layer 41b and the connection layer 41c. The via conductor 42d may electrically connect the connection layer 41c and the second electrode 30.

[0026] Here, in an embodiment, as shown in Figures 2 and 3, the connection layers 41a, 41b, and 41c may have approximately the same shape and be located at approximately the same position when viewed transparently from a direction parallel to the thickness direction of the main body portion 10, i.e., when viewed transparently along the Z-axis direction.

[0027] Furthermore, in the embodiment, the via conductors 42 a , 42 b , 42 c , and 42 d may all be located at different positions so as not to overlap with each other when viewed through in a direction parallel to the thickness direction of the main body portion 10 .

[0028] In this way, by positioning all via conductors 42a, 42b, 42c, and 42d at different positions so that they do not overlap each other in a planar view, it is possible to reduce the thermal expansion of multiple via conductors 42 accumulating in the Z-axis direction and ultimately causing the via conductors 42 to be pushed up.

[0029] Therefore, according to the embodiment, the protrusion of the via conductors 42 can be reduced.

[0030] 3, the outline of the connection layer 41 may be substantially circular, and the plurality of via conductors 42 may be arranged along the substantially circular outline of the connection layer 41 when viewed transparently along the Z-axis direction. This makes it easier to increase the distance between the plurality of via conductors 42. If the distance between the via conductors 42 is small, they are more likely to affect each other, which makes it easier for the protrusions of the via conductors 42 to accumulate, but this effect can be easily reduced.

[0031] In the embodiment, an example in which the outline of the connection layer 41 is substantially circular is shown, but the present disclosure is not limited to such an example. For example, in the present disclosure, the outline of the connection layer 41 may be a polygonal shape such as a square.

[0032] In addition, in the embodiment, the plurality of connection layers 41 and the plurality of via conductors 42 may be arranged in a spiral shape as shown in Fig. 2. In other words, in the embodiment, the current flowing through the connection portion 40 may flow in a direction that rotates along the contour of the connection layer 41 in a plan view, and may flow in a direction perpendicular to the connection layer 41 in a side view.

[0033] This shortens the conductive path in the connection portion 40, thereby improving the operating efficiency of the support member 1. Note that, although the examples in Figures 2 and 3 show an example in which the multiple connection layers 41 and the multiple via conductors 42 are arranged in a spiral shape, the present disclosure is not limited to such an example, and the multiple connection layers 41 and the multiple via conductors 42 do not have to be arranged in a spiral shape.

[0034] In addition, in an embodiment, the support member 1 may be used as an electrostatic chuck that attracts the workpiece A (see FIG. 1 ) by the Coulomb force or the Johnsen-Rahbek force generated between the workpiece A and the first electrode 20 to which a voltage is applied.

[0035] In the embodiment, the support member 1 may be used as a heater that heats the workpiece A by the first electrode 20 that is heated by applying a voltage.

[0036] In addition, in an embodiment, the support member 1 may be used in a plasma processing apparatus that applies a voltage to the first electrode 20 to generate plasma above the support surface 10a and processes the workpiece A on the support surface 10a with this plasma.

[0037] <Another Embodiment 1> Next, configurations of support members 1 according to various other embodiments will be described with reference to Fig. 4 to Fig. 8. Fig. 4 is a plan perspective view showing an example of the configuration of a connection portion 40 according to another embodiment 1. Fig. 4 is a drawing corresponding to Fig. 3 of the embodiment.

[0038] 4, in Alternative Embodiment 1, the configuration of the connection layer 41 differs from that of the above-described embodiment. Specifically, in Alternative Embodiment 1, the connection layer 41 may have an annular shape.

[0039] This also reduces the possibility that the thermal expansion of multiple via conductors 42 will accumulate in the Z-axis direction and ultimately cause the via conductors 42 to be pushed up, by positioning all via conductors 42a, 42b, 42c, and 42d at different positions so that they do not overlap each other when viewed in a plane.

[0040] Therefore, according to the first alternative embodiment, the protrusion of the via conductors 42 can be reduced.

[0041] In another embodiment 1, since the connection layer 41 has a ring shape, a pair of insulating layers positioned on either side of the connection layer 41 also come into contact with each other in the inner region 43 of the connection layer 41, thereby reducing peeling between the pair of insulating layers.

[0042] Therefore, according to the alternative embodiment 1, the reliability of the support member 1 can be improved.

[0043] Alternative Embodiment 2 Fig. 5 is a planar perspective view showing an example of the configuration of a connection portion 40 according to alternative embodiment 2. Fig. 5 is a view corresponding to Fig. 3 of the embodiment.

[0044] 5 , in Alternative Embodiment 2, the configuration of the connecting layer 41 is different from that of Alternative Embodiment 1. Specifically, in Alternative Embodiment 2, a slit 44 may be located in the annular connecting layer 41.

[0045] This also reduces the possibility that the thermal expansion of multiple via conductors 42 will accumulate in the Z-axis direction and ultimately cause the via conductors 42 to be pushed up, by positioning all via conductors 42a, 42b, 42c, and 42d at different positions so that they do not overlap each other when viewed in a plane.

[0046] Therefore, according to the second alternative embodiment, the protrusion of the via conductors 42 can be reduced.

[0047] In another embodiment 2, since the connection layer 41 has a ring shape, a pair of insulating layers positioned on either side of the connection layer 41 also come into contact with each other in the inner region 43 of the connection layer 41, thereby reducing peeling between the pair of insulating layers.

[0048] Therefore, according to the second alternative embodiment, the reliability of the support member 1 can be improved.

[0049] In another embodiment 2, a slit 44 is located in the connection layer 41, so that a pair of insulating layers positioned on either side of the connection layer 41 also come into contact with each other at the slit 44, thereby reducing peeling between the pair of insulating layers.

[0050] Therefore, according to the second alternative embodiment, the reliability of the support member 1 can be improved.

[0051] <Another embodiment 3> Fig. 6 is a planar perspective view showing an example of the configuration of a connection portion 40 according to another embodiment 3. Fig. 6 is a view corresponding to Fig. 3 of the embodiment.

[0052] 6, in Alternative Embodiment 3, the planar shape of the connection layer 41 differs from that of the above-described Alternative Embodiment 1. Specifically, in Alternative Embodiment 3, the connection layer 41 may have a substantially elliptical ring shape.

[0053] This also reduces the possibility that the thermal expansion of multiple via conductors 42 will accumulate in the Z-axis direction and ultimately cause the via conductors 42 to be pushed up, by positioning all via conductors 42a, 42b, 42c, and 42d at different positions so that they do not overlap each other when viewed in a plane.

[0054] Therefore, according to the third alternative embodiment, the protrusion of the via conductors 42 can be reduced.

[0055] In another embodiment 3, since the connection layer 41 has a ring shape, a pair of insulating layers positioned on either side of the connection layer 41 also come into contact with each other in the inner region 43 of the connection layer 41, thereby reducing peeling between the pair of insulating layers.

[0056] Therefore, according to the third alternative embodiment, the reliability of the support member 1 can be improved.

[0057] <Alternative Embodiment 4> Fig. 7 is a perspective view showing an example of the configuration of a connection portion 40 according to alternative embodiment 4. Fig. 8 is a plan view perspective view showing an example of the configuration of a connection portion 40 according to alternative embodiment 4. Figs. 7 and 8 correspond to Figs. 2 and 3 of the embodiment, respectively.

[0058] 7 and 8, another embodiment 4 differs from the above-described embodiment in the number of via conductors 42. Specifically, in another embodiment 4, the number of via conductors 42 electrically connecting adjacent connection layers 41 may be multiple, for example, two, instead of one.

[0059] In another embodiment 4, for example, two via conductors 42a may electrically connect the first electrode 20 (see FIG. 1) and the connection layer 41a, and two via conductors 42b may electrically connect the connection layer 41a and the connection layer 41b.

[0060] In another embodiment 4, two via conductors 42c may electrically connect the connection layer 41b and the connection layer 41c, and two via conductors 42d may electrically connect the connection layer 41c and the second electrode 30 (see FIG. 1).

[0061] This also reduces the possibility that the thermal expansion of multiple via conductors 42 will accumulate in the Z-axis direction and ultimately cause the via conductors 42 to be pushed up, by positioning all via conductors 42a, 42b, 42c, and 42d at different positions so that they do not overlap each other when viewed in a plane.

[0062] Therefore, according to the fourth alternative embodiment, the protrusion of the via conductors 42 can be reduced.

[0063] In another embodiment 4, there are multiple via conductors 42 that electrically connect adjacent connection layers 41, so that even if one via conductor 42 is broken, the entire connection portion 40 is less likely to be broken.

[0064] Therefore, according to the fourth alternative embodiment, the reliability of the support member 1 can be improved.

[0065] Although the examples of FIGS. 7 and 8 show an example in which there are two via conductors 42 electrically connecting adjacent connection layers 41, the present disclosure is not limited to such an example.

[0066] For example, in the present disclosure, there may be three or more via conductors 42 that electrically connect adjacent connection layers 41. Furthermore, in the present disclosure, the numbers of via conductors 42a, 42b, 42c, and 42d do not all have to be the same, and some of them may be different.

[0067] Although the embodiments of the present disclosure have been described above, the present disclosure is not limited to the above-described embodiments, and various modifications are possible without departing from the spirit of the present disclosure.

[0068] Further advantages and other aspects may readily occur to those skilled in the art. Therefore, the disclosure in its broader aspects is not limited to the specific details and representative embodiments shown and described above. Accordingly, various modifications may be made without departing from the spirit or scope of the general inventive concept as defined by the appended claims and their equivalents.

[0069] The present technology can also be configured as follows. (1) A support member comprising: a main body portion made of ceramic and having a support surface that supports an object to be processed; a first electrode located inside the main body portion; a second electrode physically and electrically connected to a power supply terminal; and a connection portion that electrically connects the first electrode and the second electrode, wherein the connection portion has a plurality of connection layers and a plurality of via conductors that are aligned along a thickness direction of the main body portion, the plurality of connection layers having substantially the same shape and positioned at substantially the same positions when viewed transparently from a direction parallel to the thickness direction, and the plurality of via conductors are all positioned at different positions so as not to overlap each other when viewed transparently from a direction parallel to the thickness direction. (2) The support member according to (1), wherein the connection layer has a substantially circular outline, and the plurality of via conductors are aligned along the substantially circular outline of the connection layer when viewed transparently from a direction parallel to the thickness direction. (3) The support member according to (1) or (2), wherein the connection layer is annular in shape. (4) The support member according to any one of (1) to (3), wherein a plurality of the connection layers and a plurality of the via conductors are arranged in a spiral in the connection portion. (5) An electrostatic chuck including the support member according to any one of (1) to (4). (6) A heater including the support member according to any one of (1) to (4). (7) A plasma processing apparatus including the support member according to any one of (1) to (4).

[0070] REFERENCE SIGNS LIST 1 Support member 10 Main body 10a Support surface 20 First electrode 30 Second electrode 40 Connection portion 41, 41a to 41c Connection layer 42, 42a to 42d Via conductor A Workpiece T Power supply terminal

Claims

1. A support member comprising: a main body made of ceramic and having a support surface for supporting an object to be processed; a first electrode located inside the main body; a second electrode physically and electrically connected to a power supply terminal; and a connection portion electrically connecting the first electrode and the second electrode, wherein the connection portion has a plurality of connection layers and a plurality of via conductors positioned side by side along the thickness direction of the main body, the plurality of connection layers having substantially the same shape and positioned at substantially the same positions when viewed transparently from a direction parallel to the thickness direction, and the plurality of via conductors being all positioned at different positions so as not to overlap each other when viewed transparently from a direction parallel to the thickness direction.

2. The support member according to claim 1, wherein the connection layer has a substantially circular outline, and the plurality of via conductors are arranged along the substantially circular outline of the connection layer when viewed through in a direction parallel to the thickness direction.

3. The support member according to claim 1 or 2, wherein the connecting layer is annular in shape.

4. A support member according to any one of claims 1 to 3, wherein a plurality of said connection layers and a plurality of said via conductors are arranged in a spiral in said connection portion.

5. An electrostatic chuck comprising the support member according to any one of claims 1 to 4.

6. A heater comprising the support member according to any one of claims 1 to 4.

7. A plasma processing apparatus comprising the support member according to any one of claims 1 to 4.

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