Sample holder

Abstract

This sample holder comprises: a ceramic body; a base member; a bonding member; a metal layer; and a heat conduction member. The ceramic body has a first surface for holding a sample and a second surface located on the opposite side of the first surface. The base member faces the second surface. The bonding member is located between the second surface and the base member. The metal layer is located inside the ceramic body, along the first surface. The heat conduction member is located inside the ceramic body and the joining member and connects the base member and the metal layer. The heat conduction member has a thermal conductivity higher than that of the bonding member and lower than that of the metal layer.

Description

Sample holder

[0001] SUMMARY OF THE INVENTION The disclosed embodiments relate to a sample holder.

[0002] In the process of manufacturing semiconductor parts, a sample holder is used to hold a workpiece such as a semiconductor wafer. One known sample holder is an electrostatic chuck, which is made by joining a ceramic body with an embedded electrode to a metal cooling plate (see, for example, Patent Document 1).

[0003] Japanese Patent Application Laid-Open No. 2015-195346

[0004] A sample holder according to one aspect of the present invention includes a ceramic body, a base member, a joining member, a metal layer, and a thermally conductive member. The ceramic body has a first surface for holding a sample and a second surface opposite the first surface. The base member faces the second surface. The joining member is located between the second surface and the base member. The metal layer is located inside the ceramic body and extends along the first surface. The thermally conductive member is located inside the ceramic body and the joining member, and connects the base member and the metal layer. The thermally conductive member has a higher thermal conductivity than the joining member and a lower thermal conductivity than the metal layer.

[0005] FIG. 1 is a cross-sectional view showing an example of a sample holder according to the first embodiment. FIG. 2 is a cross-sectional view taken along line A-A in FIG. 1. FIG. 3 is an enlarged view of region R1 in FIG. 1. FIG. 4 is a cross-sectional view showing another example of a sample holder according to the first embodiment. FIG. 5 is a cross-sectional view taken along line B-B in FIG. 4. FIG. 6 is a cross-sectional view showing an example of a sample holder according to the second embodiment. FIG. 7 is a cross-sectional view taken along line C-C in FIG. 6. FIG. 8 is a cross-sectional view showing another example of a sample holder according to the second embodiment. FIG. 9 is a cross-sectional view taken along line D-D in FIG. 8. FIG. 10 is a cross-sectional view showing an example of a sample holder according to the third embodiment. FIG. 11 is a cross-sectional view taken along line E-E in FIG. 10. FIG. 12 is a cross-sectional view showing another example of a sample holder according to the third embodiment. FIG. 13 is a cross-sectional view showing an example of a sample holder according to the fourth embodiment. FIG. 14 is a cross-sectional view taken along line F-F in FIG. 13. FIG. 15A is a plan view showing an example of a metal layer of a sample holder according to the fifth embodiment. Fig. 15B is a plan view showing another example of a metal layer of the sample holder according to the fifth embodiment. Fig. 15C is a plan view showing another example of a metal layer of the sample holder according to the fifth embodiment. Fig. 16A is a cross-sectional view showing an example of an arrangement of heat conduction members in the sample holder having the metal layer shown in Fig. 15A. Fig. 16B is a cross-sectional view showing another example of an arrangement of heat conduction members in the sample holder having the metal layer shown in Fig. 15A. Fig. 16C is a cross-sectional view showing another example of an arrangement of heat conduction members in the sample holder having the metal layer shown in Fig. 15A.

[0006] The above-described structure leaves room for improvement in terms of the thermal uniformity and heat dissipation of the ceramic body.

[0007] Therefore, it is desired to provide a sample holder with improved thermal uniformity and heat dissipation properties of the ceramic body.

[0008] Hereinafter, embodiments of the sample holder disclosed in the present application will be described with reference to the accompanying drawings. Note that this disclosure is not limited to the embodiments shown below. Furthermore, each embodiment can be appropriately combined within the scope of not causing contradictions in the content. Furthermore, the same parts in each of the following embodiments will be given the same reference numerals, and duplicated explanations will be omitted.

[0009] Furthermore, in the embodiments described below, expressions such as "constant," "perpendicular," "parallel," or "flush" may be used, but these expressions do not necessarily mean "constant," "perpendicular," "parallel," or "flush." ​​In other words, the above expressions allow for deviations due to, for example, manufacturing precision, installation precision, etc.

[0010] <First embodiment> Fig. 1 is a cross-sectional view showing an example of a sample holder according to a first embodiment. Fig. 2 is a cross-sectional view taken along line AA shown in Fig. 1. Fig. 3 is an enlarged view of region R1 shown in Fig. 1.

[0011] The sample holder 1 includes a ceramic body 10, an electrode 12, a metal layer 14, a base member 20, a bonding member 30, and a heat-conducting member 40. The sample holder 1 utilizes electrostatic force generated on the surface of the ceramic body 10 to adsorb an object to be processed, such as a semiconductor wafer.

[0012] The ceramic body 10 has, for example, a substantially circular plate shape. The ceramic body 10 has a first surface 10a and a second surface 10b located at both ends in the thickness direction. The first surface 10a is a holding surface that holds the object to be treated. The second surface 10b is located on the opposite side of the first surface 10a and is joined to the base member 20 using a joining member 30.

[0013] The ceramic body 10 may have a diameter of, for example, 50 mm to 400 mm. As shown in FIG. 3, the ceramic body 10 may have a thickness t1 from the first surface 10a to the second surface 10b of, for example, 2 mm to 15 mm.

[0014] The ceramic body 10 has insulating properties. The ceramic body 10 is made of, for example, aluminum oxide (Al ２ O ３The ceramic may contain, as a main component, a ceramic such as aluminum nitride (AlN) or aluminum nitride (AlN).

[0015] The electrode 12 is located inside the ceramic body 10. The electrode 12 extends along the first surface 10a in the vicinity of the first surface 10a. The electrode 12 is an electrostatic attraction electrode that generates an electrostatic force when a voltage is applied, thereby attracting a workpiece to the first surface 10a of the ceramic body 10. As shown in FIG. 3, the distance d1 from the first surface 10a to the electrode 12 can be, for example, 300 μm. The electrode 12 may be, for example, substantially circular in plan view. When the electrode 12 is substantially circular in plan view, the diameter of the electrode 12 can be, for example, 30 mm to 398 mm in plan view. Also, as shown in FIG. 3, the electrode 12 has a thickness t2. The thickness t2 can be, for example, in the range of 2 μm to 20 μm. The electrode 12 may contain, as a main component, a metal such as platinum (Pt) or tungsten (W).

[0016] The sample holder 1 may have a monopolar structure having one electrode 12 inside the ceramic body 10, or a bipolar structure having two electrodes 12. Furthermore, the ceramic body 10 may have a heater, an RF (radio frequency) electrode, or the like disposed inside the ceramic body 10.

[0017] The metal layer 14 is located inside the ceramic body 10. The metal layer 14 is located between the electrode 12 and the second surface 10b. The metal layer 14 has a surface 14a and a surface 14b located at both ends in the thickness direction. The surface 14a is located on the opposite side of the electrode 12. The surface 14b is located on the opposite side of the surface 14a and faces the electrode 12.

[0018] 3, the electrode 12 and the metal layer 14 are spaced apart by a distance d2. The distance d2 may be, for example, in the range of 0.3 mm to 10 mm. The metal layer 14 may be located closer to the second surface 10b than the electrode 12, or may be located closer to the electrode 12 than the second surface 10b. The metal layer 14 has a thickness t3. The thickness t3 may be, for example, in the range of 2 μm to 200 μm.

[0019] In the sample holder 1, for example, the surface temperature of the ceramic body 10 increases due to processing of the sample held on the first surface 10a side during semiconductor fabrication. The metal layer 14 can improve the thermal uniformity of the ceramic body 10, particularly the first surface 10a, by receiving heat transferred from the ceramic body 10. The metal layer 14 may have a higher thermal conductivity than the ceramic body 10. The metal layer 14 may contain, for example, a metal such as platinum (Pt) or tungsten (W) as a main component.

[0020] The base member 20 is joined to the second surface 10b of the ceramic body 10 via a joining member 30. The base member 20 may be a heat exchanger that receives heat from the ceramic body 10 and dissipates the heat to the outside. The base member 20 may have a flow path (not shown) through which a cooling medium flows. The base member 20 may be made of a metal such as aluminum or titanium. In such a case, the base member 20 may also serve as an RF electrode for the ceramic body 10, for example.

[0021] The joining member 30 is located between the second surface 10b of the ceramic body 10 and the base member 20, and joins the ceramic body 10 and the base member 20. The joining member 30 may be, for example, a silicone resin.

[0022] The heat conduction member 40 is located inside the ceramic body 10 and the bonding member 30. The heat conduction member 40 may be, for example, a columnar member that connects the base member 20 and the metal layer 14. The heat conduction member 40 receives heat transferred from the ceramic body 10 to the metal layer 14 and transfers it to the base member 20.

[0023] The heat conduction member 40 has a higher thermal conductivity than the joining member 30. Therefore, the heat conduction member 40 can quickly receive the heat transferred to the metal layer 14. The heat conduction member 40 also has a lower thermal conductivity than the metal layer 14. Because the heat conduction member 40 can receive the heat transferred from the metal layer 14 at an appropriate speed, the sample holder 1 can improve the heat dissipation of the ceramic body 10 while ensuring uniform temperature distribution of the ceramic body 10, particularly the first surface 10a.

[0024] 2, the heat conduction member 40 may be a cylindrical member having a circular cross section along the XY plane. Alternatively, the heat conduction member 40 may have an elliptical or polygonal cross section along the XY plane.

[0025] The thermal conduction member 40 may include, for example, a filler containing metal particles and / or carbon particles and a resin-based adhesive. The metal particles may contain, for example, metal elements such as gold (Au), silver (Ag), nickel (Ni), copper (Cu), zinc (Zn), or aluminum (Al), or may be an alloy such as stainless steel. The carbon particles may be, for example, graphite, carbon black, or diamond. The resin-based adhesive may be, for example, an epoxy-based adhesive or a silicone resin-based adhesive. The thermal conduction member 40 may be conductive or insulating.

[0026] As described above, the sample holder 1 according to this embodiment includes the metal layer 14 located inside the ceramic body 10 and extending along the first surface 10a, and the heat conduction member 40 located inside the ceramic body 10 and the bonding member 30 and connecting the base member 20 and the metal layer 14. The heat conduction member 40 has a thermal conductivity higher than that of the bonding member 30 and lower than that of the metal layer 14. Such a sample holder 1 improves the thermal uniformity and heat dissipation of the ceramic body 10.

[0027] Here, the thermal conductivity of the metal layer 14 can be, for example, 50 W / m·K to 450 W / m·K. The thermal conductivity of the bonding members 30 can be, for example, 0.1 W / m·K to 10 W / m·K. The thermal conductivity of the heat conduction member 40 can be, for example, 0.2 W / m·K to 200 W / m·K. The thermal conductivities of the metal layer 14, bonding members 30, heat conduction member 40, and a metal member 44 (described later) can be measured by the following method. For example, one method is to cut members made of the same material into 10 mm square pieces with a thickness of 1 mm, and measure the thermal conductivity using the laser flash method.

[0028] 3, the tip 40a of the heat conduction member 40 may be located closer to the first surface 10a than the surface 14b of the metal layer 14. That is, the heat conduction member 40 may be located so as to penetrate the metal layer 14. Furthermore, the tip 40a of the heat conduction member 40 may be in contact with the surface 14a of the metal layer 14, or may be located between the surfaces 14a and 14b.

[0029] Fig. 4 is a cross-sectional view showing another example of the sample holder according to the first embodiment, and Fig. 5 is a cross-sectional view taken along the line BB shown in Fig. 4.

[0030] 4 and 5, the heat conduction member 40 may have a cylindrical shape with a circular outer shape in a cross section along the XY plane. Alternatively, the heat conduction member 40 may have a cylindrical shape with an elliptical or polygonal outer shape in a cross section along the XY plane.

[0031] Second Embodiment Fig. 6 is a cross-sectional view showing an example of a sample holder according to a second embodiment, and Fig. 7 is a cross-sectional view taken along line CC shown in Fig. 6.

[0032] 6 and 7 , the sample holder 1 may have a plurality of heat-conducting members 40 connecting the base member 20 and the metal layer 14. With the sample holder 1 according to this embodiment, even if the temperature of the ceramic body 10 rises locally due to processing in a semiconductor manufacturing process, for example, heat from the ceramic body 10 can be quickly transferred to the base member 20 via the heat-conducting members 40 near the location of the locally increased temperature. Therefore, with this sample holder 1, the thermal uniformity and heat dissipation of the ceramic body 10 are further improved.

[0033] The intervals between the plurality of heat conduction members 40 may be the same or different. Although the example shown in Figures 6 and 7 has four heat conduction members 40, there is no limit to the number of heat conduction members 40.

[0034] Fig. 8 is a cross-sectional view showing another example of the sample holder according to the second embodiment, and Fig. 9 is a cross-sectional view taken along the line DD shown in Fig. 8.

[0035] 8 and 9 , the sample holder 1 may have multiple metal layers 14 located inside the ceramic body 10. Furthermore, a heat conduction member 40 may connect each of the multiple metal layers 14 to the base member 20. According to the sample holder 1 of this embodiment, even if the temperature of the ceramic body 10 locally rises due to processing in a semiconductor manufacturing process, for example, heat from the ceramic body 10 can be quickly conducted to the base member 20 via the metal layers 14 and heat conduction members 40 near the locally raised temperature area. Therefore, this sample holder 1 further improves the thermal uniformity and heat dissipation of the ceramic body 10.

[0036] The intervals between the multiple metal layers 14 may be the same or different. Although the example shown in Figures 8 and 9 has three metal layers 14 extending in the Y-axis direction, there is no limitation on the number and shape of the metal layers 14. Furthermore, multiple heat conduction members 40 may be connected to one metal layer 14.

[0037] <Third embodiment> Fig. 10 is a cross-sectional view showing an example of a sample holder according to a third embodiment, and Fig. 11 is a cross-sectional view taken along line EE shown in Fig. 10.

[0038] 10 and 11 , the heat conducting member 40 may have a first heat conducting member 41 located inside the ceramic body 10 and a second heat conducting member 42 located inside the bonding member 30. The second heat conducting member 42 may have a lower Young's modulus than the first heat conducting member 41.

[0039] By making the Young's modulus of the second heat conduction member 42 lower than that of the first heat conduction member 41, the stress caused by the difference in thermal expansion between the ceramic body 10 and the base member 20 can be alleviated compared to when the first heat conduction member 41 and the second heat conduction member 42 both have the same Young's modulus.

[0040] Furthermore, by making the Young's modulus of the first heat conduction member 41 higher than that of the second heat conduction member 42, the bonding strength between the heat conduction member 40 and the metal layer 14 can be increased compared to when the first heat conduction member 41 and the second heat conduction member 42 both have the same Young's modulus.

[0041] The first thermal conductive member 41 may include, for example, a filler containing metal particles and / or carbon particles and an epoxy adhesive. The second thermal conductive member 42 may include, for example, a filler containing metal particles and / or carbon particles and a silicone resin adhesive. The filler contained in the first thermal conductive member 41 and the filler contained in the second thermal conductive member 42 may be the same or different.

[0042] The Young's modulus of the first heat conducting member 41 can be set to, for example, 0.005 GPa to 10 GPa. The Young's modulus of the second heat conducting member 42 can be set to, for example, 0.001 GPa to 5 GPa. The Young's modulus of the first heat conducting member 41 and the second heat conducting member 42 can be measured by the following method. For example, a member made of the same material is cut into a piece having a thickness of 3 mm and an area of ​​10 mm. ２ One method is to prepare the sample using the ultrasonic pulse method and measure it.

[0043] Figure 12 is a cross-sectional view showing another example of the sample holder according to the third embodiment. Figure 12 corresponds to an enlarged view of region R2 shown in Figure 10. As shown in Figure 12, the width W2 of the second heat conduction member 42 in cross-sectional view may be larger than the width W1 of the first heat conduction member 41. That is, the area of ​​the second heat conduction member 42 in plan view from the first surface 10a side may be larger than that of the first heat conduction member 41. As an example of the above, the first heat conduction member 41 may overlap the second heat conduction member 42 in plan view from the first surface 10a side.

[0044] A heat conduction member 40 having a second heat conduction member 42 whose area, as viewed in plan from the first surface 10a, is larger than that of the first heat conduction member 41 has a larger cross-sectional path for heat conduction than a sample holder 1 having the same area, as viewed in plan from the first surface 10a, as the first heat conduction member 41. Therefore, a sample holder 1 having such a heat conduction member 40 improves, for example, the heat transfer capacity per unit time, and further improves the heat dissipation performance of the ceramic body 10.

[0045] The contact portion between the first heat conducting member 41 and the second heat conducting member 42 may or may not be located along the contact portion between the second surface 10b of the ceramic body 10 and the joining member 30. The tip 41a of the first heat conducting member 41 in contact with the second heat conducting member 42 may be located, for example, inside the joining member 30 or inside the ceramic body 10. The tip 42a of the second heat conducting member 42 in contact with the first heat conducting member 41 may be located, for example, inside the ceramic body 10 or inside the joining member 30.

[0046] <Fourth embodiment> Fig. 13 is a cross-sectional view showing an example of a sample holder according to a fourth embodiment, and Fig. 14 is a cross-sectional view taken along line FF shown in Fig. 13.

[0047] 13 and 14 , the sample holder 1 may have a metal member 44 located inside the heat conduction member 40 and having a higher thermal conductivity than the heat conduction member 40. The metal member 44 may be, for example, copper (Cu), gold (Au), or silver (Ag). A heat conduction member 40 having the metal member 44 inside it can receive heat transferred from the metal layer 14 more quickly than a heat conduction member 40 without the metal member 44. Therefore, the sample holder 1 according to this embodiment further improves the thermal uniformity of the ceramic body 10, particularly the first surface 10 a.

[0048] 13 , if the heat conduction member 40 has a first heat conduction member 41 and a second heat conduction member 42, and a metal member 44 is provided inside the first heat conduction member 41 near the metal layer 14, the heat dissipation performance of the ceramic body 10 is further improved. Note that the metal member 44 may be located inside the second heat conduction member 42, or may extend into the first heat conduction member 41 and the second heat conduction member 42.

[0049] Fifth Embodiment Fig. 15A is a plan view showing an example of a metal layer of a sample holder according to a fifth embodiment. Fig. 15A shows the metal layer 14 as viewed from the surface 14a side. Furthermore, Fig. 15A and Figs. 15B and 15C, which will be described later, omit the arrangement of a heat conductive member 40 connected to the metal layer 14, etc.

[0050] As shown in Fig. 15A, the metal layer 14 may have a lattice shape when viewed from above. That is, the metal layer 14 may have a lattice shape when viewed from above from the first surface 10a. The metal layer 14 may have, for example, a plurality of metal portions 141 extending in the Y-axis direction along the first surface 10a and a plurality of metal portions 142 extending in the X-axis direction perpendicular to the Y-axis direction. By forming the metal layer 14 in a lattice shape when viewed from above, stress due to the difference in thermal expansion between the ceramic body 10 and the metal layer 14 can be dispersed within the plane. This improves the durability of the sample holder 1.

[0051] Metal portion 141 is an example of a first metal portion extending in a first direction. Metal portion 142 is an example of a second metal portion extending in a second direction. As shown in Fig. 15A, in metal layer 14 having a lattice shape in plan view, multiple metal portions 141 and multiple metal portions 142 may or may not be orthogonal to each other.

[0052] 15B and 15C are plan views showing other examples of the metal layer of the sample holder according to the fifth embodiment.

[0053] As shown in Figure 15B, the metal layer 14, which has a lattice shape when viewed in a plane, may be a metal layer 14 positioned in a flat plate shape along the XY plane, with multiple openings 140 penetrating in the thickness direction (Z-axis direction).

[0054] 15C , the metal layer 14, which has a lattice-like shape in plan view, may have an annular outer periphery 143. The outer periphery 143 may be located on the edge of the metal layer 14 so as to connect the ends of the metal portions 141 and 142. A metal layer 14 having the outer periphery 143 has more paths for receiving heat from the ceramic body 10 than a metal layer 14 without the outer periphery 143. Therefore, with the sample holder 1 according to this embodiment, even if the temperature of the ceramic body 10 is locally increased due to processing in a semiconductor fabrication process, the heat transferred to the lattice portion of the metal layer 14 near the locally increased temperature is less likely to concentrate at the ends of the metal portions 141 and / or 142. Therefore, with the sample holder 1 according to this embodiment, the thermal uniformity of the ceramic body 10, particularly the first surface 10 a, is improved.

[0055] FIG. 16A is a cross-sectional view showing an example of the arrangement of heat-conducting members in the sample holder having the metal layer shown in FIG. 15A.

[0056] When viewed from above from the first surface 10a side, the heat conduction member 40 may be positioned so as to overlap the portion where the metal portions 141 and 142 extending in a lattice pattern intersect. By positioning the heat conduction member 40 at the portion where the metal portions 141 and 142 intersect, the metal layer 14 can transfer heat transferred from multiple directions (four directions in the case of FIG. 16A ) to the heat conduction member 40. Therefore, the sample holder 1 according to this embodiment improves the heat dissipation properties of the ceramic body 10.

[0057] 16B and 16C are cross-sectional views showing other examples of the arrangement of the heat conducting members in the sample holder having the metal layer shown in FIG. 15A.

[0058] When viewed from the first surface 10a side, the heat conduction member 40 may be positioned so as to overlap with a metal layer 14 different from the portion where the metal layers 14 extending in a grid pattern intersect. For example, as shown in Fig. 16B, the heat conduction member 40 may be connected to a metal portion 142 sandwiched between adjacent metal portions 141. Alternatively, the heat conduction member 40 may be connected to a metal portion 141 sandwiched between adjacent metal portions 142.

[0059] In this way, when viewed from above from the first surface 10a side, by positioning the heat conducting member 40 so that it overlaps with a metal layer 14 different from the portion where the metal layers 14 extending in a lattice pattern intersect, for example, the thermal conductivity within the metal layer 14 is increased, and the thermal uniformity within the metal layer 14 is improved. Therefore, according to the sample holder 1 of this embodiment, the thermal uniformity of the ceramic body 10, particularly the first surface 10a, is improved.

[0060] Furthermore, when viewed from the first surface 10a side, the outline of the heat conduction member 40 facing the first metal portion extending in the first direction along the first surface 10a may be located inside the outline of the first metal portion. For example, as shown in FIG. 16B , the width w3 in the Y-axis direction of the heat conduction member 40 connected to the metal portion 142 sandwiched between adjacent metal portions 141 may be smaller than the width w4 of the metal portion 142. Furthermore, when viewed from the first surface 10a side, the outline of the heat conduction member 40 facing the second metal portion extending in a second direction intersecting the first direction may be located inside the outline of the second metal portion. For example, the width w5 in the X-axis direction of the heat conduction member 40 connected to the metal portion 141 sandwiched between adjacent metal portions 142 may be smaller than the width w6 of the metal portion 142.

[0061] In this way, when viewed from above from the first surface 10a side, the contour of the heat conduction member 40 facing the first metal portion and / or the second metal portion extending in the direction along the first surface 10a is located more inward than the contour of the first metal portion and / or the second metal portion, so that the heat conduction member 40 can receive heat transferred from the metal layer 14 over the entire circumferential direction. Therefore, the sample holder 1 according to this embodiment improves the heat dissipation performance of the ceramic body 10.

[0062] The present disclosure has been described in detail above, but the present disclosure is not limited to the above-described embodiments, and various modifications, improvements, etc. are possible within the scope that does not deviate from the gist of the present disclosure.

[0063] In one embodiment, (1) a sample holder comprises: a ceramic body having a first surface for holding a sample and a second surface located opposite the first surface; a base member facing the second surface; a joining member located between the second surface and the base member; a metal layer located inside the ceramic body along the first surface; and a heat conduction member located inside the ceramic body and the joining member, connecting the base member and the metal layer, wherein the heat conduction member has a thermal conductivity higher than that of the joining member and lower than that of the metal layer.

[0064] (2) The sample holder of (1) above may have a plurality of the heat conducting members.

[0065] (3) In the sample holder of (1) or (2) above, the heat conduction member may include a first heat conduction member located inside the ceramic body, and a second heat conduction member located inside the joining member and having a Young's modulus lower than that of the first heat conduction member.

[0066] (4) In the sample holder of (3) above, the first heat conducting member may overlap the second heat conducting member when viewed from above from the first surface side.

[0067] (5) In the sample holder according to any one of (1) to (4) above, the metal layer may have a lattice shape when viewed from the first surface side.

[0068] (6) In the sample holder of any one of (1) to (5) above, the metal layer may have an annular outer periphery when viewed in plan from the first surface side.

[0069] (7) In the sample holder of (5) above, the metal layer includes a first metal portion extending in a first direction along the first surface, and when viewed in a plan view from the first surface side, the outline of the heat conduction member facing the first metal portion may be located inside the outline of the first metal portion.

[0070] (8) In the sample holder of (5) above, when viewed in plan from the first surface side, the heat conduction member may be positioned so as to overlap with the intersection of the metal layers extending in a lattice pattern.

[0071] (9) In the sample holder of (5) above, when viewed in a plan view from the first surface side, the heat conduction member may be positioned so as to overlap with a metal layer different from the portion where the metal layers extending in a lattice pattern intersect.

[0072] (10) In any one of the sample holders (1) to (9) above, a metal member may be located inside the heat conducting member and have a higher thermal conductivity than the heat conducting member.

[0073] Further advantages and modifications will 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.

[0074] REFERENCE SIGNS LIST 1 sample holder 10 ceramic body 10a first surface 10b second surface 12 electrode 14 metal layer 20 base member 30 joining member 40 heat conducting member 41 first heat conducting member 42 second heat conducting member 44 metal member 141 metal portion (first metal portion) 142 metal portion (second metal portion)

Claims

1. A sample holder comprising: a ceramic body having a first surface for holding a sample and a second surface located opposite the first surface; a base member facing the second surface; a joining member located between the second surface and the base member; a metal layer located inside the ceramic body along the first surface; and a heat conducting member located inside the ceramic body and the joining member and connecting the base member and the metal layer, wherein the heat conducting member has a higher thermal conductivity than the joining member and a lower thermal conductivity than the metal layer.

2. The sample holder according to claim 1, comprising a plurality of said heat conducting members.

3. A sample holder as described in claim 1 or 2, wherein the heat conduction member comprises a first heat conduction member located inside the ceramic body, and a second heat conduction member located inside the joining member and having a Young's modulus lower than that of the first heat conduction member.

4. A sample holder according to claim 3, wherein the first heat conducting member overlaps the second heat conducting member when viewed in plan from the first surface side.

5. A sample holder according to any one of claims 1 to 4, wherein the metal layer has a lattice pattern when viewed in plan from the first surface side.

6. A sample holder according to any one of claims 1 to 5, wherein the metal layer has an annular outer periphery when viewed in plan from the first surface side.

7. A sample holder as described in claim 5, wherein the metal layer includes a first metal portion extending in a first direction along the first surface, and when viewed in a plan view from the first surface side, the outline of the heat conduction member facing the first metal portion is located inside the outline of the first metal portion.

8. A sample holder as described in claim 5, wherein, when viewed in a plan view from the first surface side, the heat conduction member is positioned so as to overlap with the intersection of the metal layers extending in a lattice pattern.

9. A sample holder as described in claim 5, wherein, when viewed in a plane from the first surface side, the heat conduction member is positioned so as to overlap with a metal layer different from the portion where the metal layers extending in a grid pattern intersect.

10. A sample holder according to any one of claims 1 to 9, which has a metal member located inside said heat conducting member and having a higher thermal conductivity than said heat conducting member.

Images