Sample holder
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Filing Date
- 2024-08-27
- Publication Date
- 2026-05-11
Abstract
Description
Sample holder
[0001] SUMMARY OF THE INVENTION The disclosed embodiments relate to a sample holder.
[0002] In the process of manufacturing semiconductor parts, electrostatic chucks are used as sample holders to hold workpieces such as semiconductor wafers that are to be subjected to plasma processing. These electrostatic chucks are constructed, for example, by bonding a ceramic substrate, in which an electrostatic attraction electrode and a heater electrode are embedded, to a metal cooling member.
[0003] This cooling member is formed with a flow path for passing a cooling medium to cool the ceramic substrate and maintain the object to be treated at a desired temperature (see, for example, Patent Document 1).
[0004] Japanese Patent Application Laid-Open No. 2014-183077
[0005] A sample holder according to one aspect of the embodiment includes a ceramic substrate, a bonding material, and a cooling member. The ceramic substrate has a first surface on which a sample is held and a second surface opposite the first surface. The bonding material is positioned between the ceramic substrate and the cooling member. The cooling member is bonded to the second surface of the ceramic substrate, and has a flow path through which a refrigerant can flow. The cooling member also includes a first base, a second base, and a first member. The metal first base is positioned closer to the ceramic substrate than the flow path. The metal second base is positioned farther from the ceramic substrate than the first base, and is bonded to the first base to form a groove that becomes the flow path. The first member is positioned closer to the ceramic substrate than the flow path, and has a lower thermal conductivity than the first base.
[0006] FIG. 1 is a perspective view showing the configuration of a sample holder according to an embodiment. FIG. 2 is a schematic diagram showing a cross section of the sample holder according to an embodiment. FIG. 3 is an enlarged cross-sectional view showing the configuration of the flow path and the first member and its surroundings of the sample holder according to an embodiment. FIG. 4 is a diagram for explaining the heat flow inside a cooling member in a reference example. FIG. 5 is a diagram for explaining the heat flow inside a cooling member according to an embodiment. FIG. 6 is an enlarged cross-sectional view showing the configuration of the flow path and the first member and its surroundings of the sample holder according to another embodiment 1. FIG. 7 is an enlarged cross-sectional view showing the configuration of the flow path and the first member and its surroundings of the sample holder according to another embodiment 2. FIG. 8 is an enlarged cross-sectional view showing the configuration of the flow path and the first member and its surroundings of the sample holder according to another embodiment 3. FIG. 9 is an enlarged cross-sectional view showing the configuration of the flow path and the first member and its surroundings of the sample holder according to another embodiment 4. FIG. 10 is an enlarged cross-sectional view showing the configuration of the flow path and the first member and its surroundings of the sample holder according to another embodiment 5. FIG. 11 is an enlarged cross-sectional view showing the configuration of the flow path and the first member and its surroundings of the sample holder according to another embodiment 6. Fig. 12 is an enlarged cross-sectional view showing the configuration of the flow channel and the first member and their surroundings of a sample holder according to another embodiment 7. Fig. 13 is an enlarged cross-sectional view showing the configuration of the flow channel and the first member and their surroundings of a sample holder according to another embodiment 8. Fig. 14 is an enlarged cross-sectional view showing the configuration of the flow channel and the first member and their surroundings of a sample holder according to another embodiment 9. Fig. 15 is an enlarged cross-sectional view showing the configuration of the flow channel and the first member and their surroundings of a sample holder according to another embodiment 10. Fig. 16 is an enlarged cross-sectional view showing the configuration of the flow channel and the first member and their surroundings of a sample holder according to another embodiment 11. Fig. 17 is an enlarged cross-sectional view showing the configuration of the flow channel and the first member and their surroundings of a sample holder according to another embodiment 12.
[0007] Hereinafter, embodiments of the sample holder disclosed in the present application will be described with reference to the accompanying drawings. Note that the present 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.
[0008] 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.
[0009] In the process of manufacturing semiconductor parts, electrostatic chucks are used as sample holders to hold workpieces such as semiconductor wafers that are to be subjected to plasma processing. These electrostatic chucks are constructed, for example, by bonding a ceramic substrate, in which an electrostatic attraction electrode and a heater electrode are embedded, to a metal cooling member.
[0010] The cooling member is formed with a flow path for passing a cooling medium to cool the ceramic substrate and maintain the object to be treated at a desired temperature.
[0011] However, the above-described conventional technology leaves room for further improvement in terms of improving the in-plane temperature uniformity of the upper surface of the cooling member, which can cause problems with the in-plane temperature uniformity of the workpiece, potentially reducing the yield of plasma processing of the workpiece.
[0012] Therefore, it is desired to realize a technology that can solve the above problems and improve the in-plane temperature uniformity of the upper surface of the cooling member of the sample holder.
[0013] <Embodiment> First, the configuration of a sample holder 100 according to an embodiment will be described with reference to Figures 1 to 5. Figure 1 is a perspective view showing the configuration of the sample holder 100 according to an embodiment. As shown in Figure 1, the sample holder 100 has a structure in which a ceramic substrate 110 and a cooling member 120 are joined together.
[0014] The ceramic substrate 110 uses electrostatic force to attract a workpiece (not shown) such as a semiconductor wafer on the first surface 110a. The workpiece is an example of a sample. The ceramic substrate 110 is a member formed into a substantially circular disk shape from a ceramic-containing raw material.
[0015] The ceramic substrate 110 is made of, for example, aluminum oxide (Al ２ O３ ), aluminum nitride (AlN), yttria (Y ２ O ３ ), cordierite, silicon carbide (SiC) or silicon nitride (Si ３ N ４ ) as its main ingredient.
[0016] The cooling member 120 is a support member that supports the ceramic substrate 110. The cooling member 120 is attached to, for example, a semiconductor manufacturing device, and causes the sample holder 100 to function as a semiconductor holder for holding a workpiece such as a semiconductor wafer. The cooling member 120 is, for example, a circular metallic member that has a cylindrical protrusion on the ceramic substrate 110 side.
[0017] Fig. 2 is a schematic diagram showing a cross section of the sample holder 100 according to the embodiment. As shown in Fig. 2, the sample holder 100 is configured by bonding a ceramic substrate 110 and a cooling member 120 to each other.
[0018] The ceramic substrate 110 has a first surface 110a and a second surface 110b. A workpiece (not shown) such as a semiconductor wafer is held on the first surface 110a. The second surface 110b is located on the opposite side to the first surface 110a.
[0019] The workpiece held on first surface 110a of ceramic substrate 110 is subjected to plasma processing, for example, by generating plasma above first surface 110a. This plasma can be generated, for example, by applying high-frequency power to an electrode (not shown) facing first surface 110a to excite a gas.
[0020] For example, an electrostatic attraction electrode 111 and a heater electrode 112 may be provided inside the ceramic substrate 110. The electrostatic attraction electrode 111 is a conductive member containing a metal such as platinum (Pt), tungsten (W), or molybdenum (Mo) as a main component.
[0021] In the sample holder 100, when a voltage is applied to the electrostatic attraction electrode 111, an electrostatic force is generated, and the sample holder 100 functions as an electrostatic chuck, and the object to be processed is attracted to the first surface 110a of the ceramic substrate 110 by the electrostatic force.
[0022] The heater electrode 112 is made of a resistance heating element containing a conductive material (for example, tungsten, molybdenum, etc.). When a voltage is applied to the heater electrode 112 in the sample holder 100, the heater electrode 112 generates heat. This causes the temperature of the workpiece to rise to a desired temperature.
[0023] The heater electrode 112 is located inside the ceramic substrate 110 so that its outer shape is circular and it forms a predetermined pattern such as a meandering or spiral pattern in a plan view.
[0024] The cooling member 120 is bonded to the second surface 110b of the ceramic substrate 110. The cooling member 120 may be bonded to the second surface 110b via, for example, a bonding material 113. That is, the bonding material 113 may be located between the ceramic substrate 110 and the cooling member 120. As the bonding material 113, for example, an adhesive such as a silicone resin may be used.
[0025] Cooling member 120 has a first base 121 and a second base 122. Furthermore, a flow path 123 is formed inside cooling member 120. First base 121 is located closer to ceramic substrate 110 than flow path 123. First base 121 is, for example, a circular metal member having a cylindrical protrusion on the ceramic substrate 110 side.
[0026] The first base 121 has a first surface 121a and a second surface 121b. The first surface 121a faces the second surface 110b of the ceramic substrate 110, and they are bonded to each other via a bonding material 113. The second surface 121b is located on the opposite side to the first surface 121a.
[0027] The second base 122 is located farther from the ceramic substrate 110 than the first base 121. The second base 122 is, for example, a circular member made of metal.
[0028] The second base 122 has a first surface 122a and a second surface 122b. The first surface 122a faces the second surface 121b of the first base 121, and they are bonded to each other using a bonding material (not shown) or the like. The second surface 122b is located on the opposite side to the first surface 122a.
[0029] Furthermore, grooves 122c are formed on the first surface 122a of the second base 122, which become flow paths 123 when bonded to the first base 121. The grooves 122c are positioned on the first surface 122a of the second base 122 so that, for example, in a plan view, the grooves 122c form a predetermined pattern such as a meandering or spiral shape and have a circular outer shape.
[0030] That is, the flow path 123 formed inside the cooling member 120 is located inside the cooling member 120 so that, when viewed in a plane, it has a predetermined pattern such as a meandering or spiral shape and has a circular outer shape.
[0031] FIG. 3 is an enlarged cross-sectional view showing the configuration around the flow channel 123 and the first member 124 of the sample holder 100 according to the embodiment, and is an enlarged cross-sectional view of the region X surrounded by the dashed line in FIG.
[0032] 3, in the sample holder 100 according to the embodiment, the cooling member 120 has a first member 124. The first member 124 is located on the ceramic substrate 110 (see FIG. 2) side of the flow path 123, and is made of a material with a lower thermal conductivity than the first base 121.
[0033] The first member 124 according to the embodiment may be primarily composed of a non-magnetic metal material such as titanium (Ti), zirconium (Zr), niobium (Nb), or stainless steel, and more preferably is primarily composed of titanium, which can improve corrosion resistance against the refrigerant flowing through the flow path 123.
[0034] The first member 124 according to the embodiment is not limited to being made of the above-mentioned metal materials, but may be made of various ceramic materials.
[0035] In this manner, in the embodiment, by providing the first member 124 having low thermal conductivity on the ceramic substrate 110 (see FIG. 2 ) side of the flow path 123, it is possible to improve the in-plane thermal uniformity of the upper surface (first surface 121 a (see FIG. 2 ) of the first base 121) of the cooling member 120. The reason for this will be described with reference to FIGS. 4 and 5 .
[0036] 4 is a diagram for explaining the flow of heat inside the cooling member 120 of the reference example. Note that the cooling member 120 of the reference example does not include the first member 124 shown in FIG.
[0037] As shown in Figure 4, in the reference example, the heat H1 transferred from the ceramic substrate 110 (see Figure 1) located directly above the flow path 123 has a shorter transfer path than the heat H2 transferred from the ceramic substrate 110 that is not located directly above the flow path 123.
[0038] In other words, in the reference example, the upper surface of the cooling member 120 located directly above the flow path 123 is at a shorter distance from the flow path 123 than the upper surface of the cooling member 120 that is not directly above the flow path 123, and therefore has a lower temperature.
[0039] Therefore, with the cooling member 120 of the reference example, it is difficult to uniformly cool the entire upper surface of the cooling member 120. This phenomenon becomes more pronounced when an attempt is made to increase the cooling efficiency by thinning the entire cooling member 120.
[0040] 5 is a diagram illustrating the flow of heat inside the cooling member 120 according to the embodiment. Unlike the reference example described above, in the cooling member 120 according to the embodiment, as shown in FIG. 5, a first member 124 with low thermal conductivity is disposed on the path of heat H1, which has a short transmission path.
[0041] This reduces the transfer efficiency of the heat H1 compared to when the first member 124 is not provided, and therefore the transfer efficiency of the heat H2, which has a longer transfer path, can be made equal to the transfer efficiency of the heat H1. Therefore, according to the embodiment, the in-plane temperature uniformity of the upper surface of the cooling member 120 can be improved.
[0042] Returning to the description of Fig. 3, in the embodiment, as shown in Fig. 3, the width W1 of the first member 124 may be larger than the width W2 of the flow path 123 in a cross-sectional view. This allows heat from the refrigerant flowing through the flow path 123 to be transferred preferentially from the side surface 123a of the flow path 123 via a portion where no flow path 123 exists, rather than being transferred directly above the flow path 123.
[0043] Therefore, according to the embodiment, the in-plane temperature uniformity of the upper surface of the cooling member 120 can be further improved.
[0044] 3, the first member 124 may face the flow path 123. This allows the main path of heat transfer from the refrigerant flowing through the flow path 123 to be the side surface 123a of the flow path 123 rather than the top surface of the flow path 123 (i.e., the second surface 124b of the first member 124).
[0045] Therefore, according to the embodiment, the in-plane temperature uniformity of the upper surface of the cooling member 120 can be further improved.
[0046] 2, the second surface 121b of the first base 121 that contacts the second base 122 may be a flat surface. In other words, the second surface 121b of the first base 121 does not need to have any protrusions or recesses, and may simply extend flat, for example.
[0047] When the second surface 121b of the first base 121 is flat, the heat transfer conditions at the joint surface between the first base 121 and the second base 122 are consistent, compared to when the second surface 121b is uneven, and therefore the heat conduction in the surface direction can be made uniform.
[0048] Therefore, according to the embodiment, the in-plane temperature uniformity of the upper surface of the cooling member 120 can be further improved.
[0049] 2, the thickness of the portion of the first base 121 located above the first member 124 (i.e., on the ceramic substrate 110 side) may be uniform. This makes the heat capacity of this portion the same, thereby further improving the in-plane temperature uniformity of the upper surface of the cooling member 120.
[0050] In addition, in the embodiment, the first member 124 may be rectangular (i.e., plate-shaped) as shown in Fig. 3. In other words, in the embodiment, the thickness of the first member 124 may be constant, and neither a protrusion nor a recess may be provided on the surface of the first member 124.
[0051] In this way, when the first member 124 is rectangular, the heat conduction in the lateral direction is uniformly transferred across the plane. In other words, when the first member 124 is rectangular, the heat capacity is uniform across the plane, resulting in excellent heat uniformity and consistent heat transfer conditions.
[0052] Therefore, according to the embodiment, it is possible to further improve the in-plane temperature uniformity of the upper surface of the cooling member 120. Note that in the embodiment, the plate-shaped first member 124 may be substantially parallel to the first base 121 and the second base 122.
[0053] In addition, in the embodiment, the second base 122 may have a higher thermal conductivity than the first member 124. This makes it easier for heat to be transferred from the refrigerant flowing through the flow path 123 from the side surface 123 a of the flow path 123 to pass through a portion where there is no flow path 123, and therefore the in-plane temperature of the upper surface of the cooling member 120 tends to become uniform.
[0054] The first base 121 and the second base 122 may be made of a composite material such as AlSiC or SiSiC, or a non-magnetic metal material such as aluminum or copper, and are more preferably made of AlSiC, which can improve corrosion resistance against the refrigerant flowing through the flow path 123.
[0055] The first base 121 and the second base 122 may be made of the same material or different materials.
[0056] On the other hand, since the first substrate 121 and the second substrate 122 are made of the same material, the thermal expansion coefficients of both substrates can be made the same, which reduces the warping of the entire cooling member 120 due to high heat, for example, during plasma processing of the object to be processed at high temperatures.
[0057] In addition, in the embodiment, the second base 122 may have a step portion 122d (see FIG. 3) at the opening of the groove 122c. This allows the step portion 122d to easily support the first member 124, which has a width W1 larger than that of the flow path 123. Therefore, according to the embodiment, the manufacturing process of the cooling member 120 can be simplified.
[0058] In addition, in the embodiment, the first member 124 may be a single piece having a planar shape corresponding to the planar shape of the groove 122c. This allows the flow path 123 (groove 122c) to be covered from above without any gaps. Therefore, according to the embodiment, the in-plane temperature uniformity of the upper surface of the cooling member 120 can be further improved.
[0059] Furthermore, in the embodiment, the first member 124 is a single piece having a planar shape corresponding to the planar shape of the groove 122c, which makes it possible to easily attach the first member 124 to the second base 122. Therefore, according to the embodiment, the manufacturing process of the cooling member 120 can be simplified.
[0060] In the present disclosure, the first member 124 is not limited to being a single piece, but may be divided into a plurality of members. This also allows the flow path 123 (groove 122c) to be covered from above without any gaps, thereby further improving the in-plane temperature uniformity of the upper surface of the cooling member 120.
[0061] <Another embodiment 1> Next, various other embodiments of the present disclosure will be described with reference to Fig. 6 to Fig. 16. Fig. 6 is an enlarged cross-sectional view showing the configuration of the flow channel 123 and the first member 124 of the sample holder 100 according to another embodiment 1.
[0062] 6, in the sample holder 100 according to another embodiment 1, the thickness L1 of the first member 124 is different from that of the above-described embodiment. Specifically, in another embodiment 1, the thickness L1 of the first member 124 may be smaller than the height L2 of the step portion 122d in the second base 122.
[0063] In this way, since the thickness L1 of the first member 124, which has low thermal conductivity, is smaller than the height L2 of the step portion 122d of the second base 122, which has high thermal conductivity, heat is easily transferred from the flow path 123 to the first base 121 via the side surface 123a of the flow path 123 and the second base 122.
[0064] Therefore, according to the first alternative embodiment, the in-plane temperature uniformity of the upper surface of the cooling member 120 can be further improved.
[0065] In another embodiment 1, as shown in FIG. 6, a second member 125 may be positioned between the first surface 124a of the first member 124 on the ceramic substrate 110 (see FIG. 2) side and the first base 121.
[0066] In another embodiment 1, the second member 125 may be made of a material having a higher thermal conductivity than the first member 124 and a lower thermal conductivity than the first base 121. The second member 125 is made of, for example, tin (Sn) or the like as a main component.
[0067] In this way, by positioning the second member 125, which has a lower thermal conductivity than the first base 121, directly above the flow path 123, heat H1 (see FIG. 5) from directly above the flow path 123 is less likely to be rapidly transferred.
[0068] Therefore, according to the first alternative embodiment, the in-plane temperature uniformity of the upper surface of the cooling member 120 can be further improved.
[0069] The second member 125 may be configured as a part of the bonding material that bonds the first base 121 and the second base 122. This allows the second member 125 to be disposed at the same time as the first base 121 and the second base 122 are bonded, thereby simplifying the manufacturing process of the cooling member 120.
[0070] <Second and Third Alternative Embodiments> FIG. 7 is an enlarged cross-sectional view showing the configuration of the flow channel 123 and the first member 124 of the sample holder 100 according to a second alternative embodiment.
[0071] 7, in the sample holder 100 according to another embodiment 2, a first region A having a lower thermal conductivity than the first member 124 may be located between the side surface 124c of the first member 124 and the second base 122. For example, in the example of FIG. 7, a gap is located in this first region A.
[0072] In this way, by placing the first region A, which has a lower thermal conductivity than the first member 124, on the side of the first member 124, heat is transferred from the side surface 123a of the flow path 123 via a location where there is no flow path 123, thereby reducing the cooling function directly above the flow path 123.
[0073] Therefore, according to the second alternative embodiment, the in-plane temperature uniformity of the upper surface of the cooling member 120 can be further improved.
[0074] In another embodiment 2, by placing a gap between the side surface 124c of the first member 124 and the second base 122, the thermal conductivity of the first region A can be made the lowest, and this gap can alleviate the thermal stress caused by the difference in thermal expansion between the first member 124 and the second base 122.
[0075] It should be noted that the present invention is not limited to a case where a gap is located in the first region A. Fig. 8 is an enlarged cross-sectional view showing the configuration of the flow channel 123 and the first member 124 of the sample holder 100 according to another embodiment 3.
[0076] 8, a resin 126 may be located in the first region A. The resin 126 may have a lower thermal conductivity than the first member 124.
[0077] In this way, by placing resin 126, which has a lower thermal conductivity than first member 124, on the side of first member 124, heat is transferred from the side surface 123a of flow path 123 via a location where there is no flow path 123, thereby reducing the cooling function directly above flow path 123.
[0078] Therefore, according to the third alternative embodiment, the in-plane temperature uniformity of the upper surface of the cooling member 120 can be further improved.
[0079] In another embodiment 3, by placing resin 126 on the side of first member 124, it is possible to reduce the penetration of the bonding material (not shown) that bonds first base 121 and second base 122 into the side of first member 124.
[0080] <Alternative Embodiment 4> Fig. 9 is an enlarged cross-sectional view showing the configuration around the flow path 123 and the first member 124 of the sample holder 100 according to Alternative Embodiment 4. As shown in Fig. 9, in the sample holder 100 according to Alternative Embodiment 4, the position of the resin 126 differs from that of the above-mentioned Alternative Embodiment 3 (see Fig. 8).
[0081] Specifically, in another embodiment 4, a plurality of resins 126 may be positioned so as to sandwich a corner 124 d of the first member 124 located at the step portion 122 d of the second base 122 .
[0082] The sample holder 100 including the cooling member 120 is used in an environment where temperature changes drastically, and therefore stress may be concentrated at the interface between the first member 124 and the second base 122, making them prone to peeling. On the other hand, in another embodiment 4, stress can be alleviated by arranging multiple pieces of highly elastic resin 126 so as to sandwich the corners 124d of the first member 124 as shown in Figure 9.
[0083] Therefore, according to the embodiment, the reliability of the cooling member 120 can be improved.
[0084] <Another embodiment 5> Figure 10 is an enlarged cross-sectional view showing the configuration around the flow channel 123 and the first member 124 of the sample holder 100 according to another embodiment 5. As shown in Figure 10, in the sample holder 100 according to another embodiment 5, the position of the first member 124 differs from that of the embodiment described above (see Figure 3).
[0085] Specifically, in another embodiment 5, the first member 124 is located inside the cooling member 120 so as to be embedded in the second surface 121b of the first base 121. For example, in another embodiment 5, the second surface 124b of the first member 124 (see FIG. 6 ) and the second surface 121b of the first base 121 are substantially flush with each other.
[0086] As a result, in Alternative Embodiment 5, similar to the above-described embodiment, the first member 124 faces the flow path 123. Also, in Alternative Embodiment 5, similar to the above-described embodiment, the width W1 (see FIG. 3) of the first member 124 is larger than the width W2 (see FIG. 3) of the flow path 123.
[0087] Even with this configuration, the first member 124, which has low thermal conductivity, is located on the path of heat H1 (see FIG. 5), which has a short transmission path, so that the transmission efficiency of heat H2 (see FIG. 5), which has a long transmission path, and the transmission efficiency of heat H1 can be made equal. Therefore, according to another embodiment 5, the in-plane temperature uniformity of the upper surface of the cooling member 120 can be improved.
[0088] In another embodiment 5, the first member 124 faces the flow path 123, so that the main path of heat transfer from the refrigerant flowing through the flow path 123 can be the side 123a of the flow path 123 rather than the top surface of the flow path 123 (i.e., the second surface 124b of the first member 124).
[0089] Therefore, according to the fifth alternative embodiment, the in-plane temperature uniformity of the upper surface of the cooling member 120 can be further improved.
[0090] In another embodiment 5, since the width W1 of the first member 124 is larger than the width W2 of the flow path 123, heat transfer from the refrigerant flowing through the flow path 123 is prioritized from the side surface 123a of the flow path 123 via a location where there is no flow path 123, rather than being transferred directly above the flow path 123.
[0091] Therefore, according to the fifth alternative embodiment, the in-plane temperature uniformity of the upper surface of the cooling member 120 can be further improved.
[0092] <Alternative Embodiment 6> Figure 11 is an enlarged cross-sectional view showing the configuration around the flow path 123 and the first member 124 of the sample holder 100 according to alternative embodiment 6. As shown in Figure 11, in the sample holder 100 according to alternative embodiment 6, the position of the first member 124 differs from that of the above-mentioned alternative embodiment 5 (see Figure 10).
[0093] Specifically, in another embodiment 6, the first member 124 is located inside the cooling member 120 so as to be embedded inside the first base 121. Note that in another embodiment 6, similar to the above-described embodiment, the width W1 (see FIG. 3) of the first member 124 is larger than the width W2 (see FIG. 3) of the flow path 123.
[0094] Even with this configuration, the first member 124, which has low thermal conductivity, is located on the path of heat H1 (see FIG. 5), which has a short transmission path, so that the transmission efficiency of heat H2 (see FIG. 5), which has a long transmission path, and the transmission efficiency of heat H1 can be made equal. Therefore, according to another embodiment 6, the in-plane temperature uniformity of the upper surface of the cooling member 120 can be improved.
[0095] In another embodiment 6, since the width W1 of the first member 124 is larger than the width W2 of the flow path 123, heat transfer from the refrigerant flowing through the flow path 123 is prioritized from the side surface 123a of the flow path 123 via a location where there is no flow path 123, rather than being transferred directly above the flow path 123.
[0096] Therefore, according to the sixth alternative embodiment, the in-plane temperature uniformity of the upper surface of the cooling member 120 can be further improved.
[0097] <Alternative Embodiment 7> Fig. 12 is an enlarged cross-sectional view showing the configuration around the flow channel 123 and the first member 124 of the sample holder 100 according to Alternative Embodiment 7. As shown in Fig. 12, in the sample holder 100 according to Alternative Embodiment 7, the width W1 of the first member 124 differs from that of the above-described embodiment (see Fig. 3).
[0098] Specifically, in another embodiment 7, the width W1 of the first member 124 is approximately equal to the width W2 of the flow path 123. Note that in another embodiment 7, the first member 124 faces the flow path 123, similar to the above-described embodiments.
[0099] Even with this configuration, the first member 124, which has low thermal conductivity, is located on the path of heat H1 (see FIG. 5), which has a short transmission path, so that the transmission efficiency of heat H2 (see FIG. 5), which has a long transmission path, and the transmission efficiency of heat H1 can be made equal. Therefore, according to another embodiment 7, the in-plane temperature uniformity of the upper surface of the cooling member 120 can be improved.
[0100] In another embodiment 7, the first member 124 faces the flow path 123, so that the main path of heat transfer from the refrigerant flowing through the flow path 123 can be the side surface 123a of the flow path 123 rather than the top surface of the flow path 123 (i.e., the second surface 124b of the first member 124 (see Figure 6)).
[0101] Therefore, according to the seventh alternative embodiment, the in-plane temperature uniformity of the upper surface of the cooling member 120 can be further improved.
[0102] <Another embodiment 8> Figure 13 is an enlarged cross-sectional view showing the configuration around the flow channel 123 and the first member 124 of the sample holder 100 according to another embodiment 8. As shown in Figure 13, in the sample holder 100 according to another embodiment 8, the position of the first member 124 differs from that of the above-mentioned another embodiment 7 (see Figure 12).
[0103] Specifically, in another embodiment 8, the first member 124 is located inside the cooling member 120 so as to be embedded in the second surface 121b of the first base 121. For example, in another embodiment 8, the second surface 124b of the first member 124 (see FIG. 6 ) and the second surface 121b of the first base 121 are substantially flush with each other.
[0104] As a result, in Alternative Embodiment 8, similar to the above-described Alternative Embodiment 7, the first member 124 faces the flow path 123. Also, in Alternative Embodiment 8, similar to the above-described Alternative Embodiment 7, the width W1 (see FIG. 12) of the first member 124 and the width W2 (see FIG. 12) of the flow path 123 are approximately equal.
[0105] Even with this configuration, the first member 124, which has low thermal conductivity, is located on the path of heat H1 (see FIG. 5), which has a short transmission path, so that the transmission efficiency of heat H2 (see FIG. 5), which has a long transmission path, and the transmission efficiency of heat H1 can be made equal. Therefore, according to another embodiment 8, the in-plane temperature uniformity of the upper surface of the cooling member 120 can be improved.
[0106] In another embodiment 8, the first member 124 faces the flow path 123, so that the main path of heat transfer from the refrigerant flowing through the flow path 123 can be the side 123a of the flow path 123 rather than the top surface of the flow path 123 (i.e., the second surface 124b of the first member 124).
[0107] Therefore, according to the eighth alternative embodiment, the in-plane temperature uniformity of the upper surface of the cooling member 120 can be further improved.
[0108] <Another Embodiment 9> Figure 14 is an enlarged cross-sectional view showing the configuration around the flow path 123 and the first member 124 of the sample holder 100 according to another embodiment 9. As shown in Figure 14, in the sample holder 100 according to another embodiment 9, the position of the first member 124 differs from that of the above-mentioned another embodiment 8 (see Figure 13).
[0109] Specifically, in another embodiment 9, the first member 124 is located inside the cooling member 120 so as to be embedded inside the first base 121. Note that in another embodiment 9, similar to the above-described another embodiment 8, the width W1 (see FIG. 12) of the first member 124 and the width W2 (see FIG. 12) of the flow path 123 are approximately equal.
[0110] Even with this configuration, the first member 124, which has low thermal conductivity, is located on the path of heat H1 (see FIG. 5), which has a short transmission path, so that the transmission efficiency of heat H2 (see FIG. 5), which has a long transmission path, and the transmission efficiency of heat H1 can be made equal. Therefore, according to another embodiment 9, the in-plane temperature uniformity of the upper surface of the cooling member 120 can be improved.
[0111] <Another Embodiment 10> Fig. 15 is an enlarged cross-sectional view showing the configuration around the flow channel 123 and the first member 124 of the sample holder 100 according to another embodiment 10. As shown in Fig. 15, in the sample holder 100 according to another embodiment 10, the width W1 of the first member 124 is different from that of the embodiment described above (see Fig. 3).
[0112] Specifically, in another embodiment 10, the width W1 of the first member 124 is smaller than the width W2 of the flow path 123. In this another embodiment 10, for example, the first surface 124a (see FIG. 6) of the first member 124 and the second surface 121b of the first base 121 may be joined together with a bonding material (not shown) or the like.
[0113] In another embodiment 10, the first member 124 faces the flow path 123, as in the above-described embodiment.
[0114] Even with this configuration, the first member 124, which has low thermal conductivity, is located on the path of heat H1 (see FIG. 5), which has a short transmission path, so that the transmission efficiency of heat H2 (see FIG. 5), which has a long transmission path, and the transmission efficiency of heat H1 can be made equal. Therefore, according to another embodiment 10, the in-plane temperature uniformity of the upper surface of the cooling member 120 can be improved.
[0115] In another embodiment 10, the first member 124 faces the flow path 123, so that the main path of heat transfer from the refrigerant flowing through the flow path 123 can be the side surface 123a of the flow path 123 rather than the top surface of the flow path 123 (i.e., the second surface 124b of the first member 124 (see Figure 6)).
[0116] Therefore, according to another embodiment 10, the in-plane temperature uniformity of the upper surface of the cooling member 120 can be further improved.
[0117] <Another embodiment 11> Figure 16 is an enlarged cross-sectional view showing the configuration around the flow path 123 and the first member 124 of the sample holder 100 according to another embodiment 11. As shown in Figure 16, in the sample holder 100 according to another embodiment 11, the position of the first member 124 differs from that of the above-mentioned another embodiment 10 (see Figure 15).
[0118] Specifically, in another embodiment 11, the first member 124 is located inside the cooling member 120 so as to be embedded in the second surface 121b of the first base 121. For example, in another embodiment 11, the second surface 124b of the first member 124 (see FIG. 6 ) and the second surface 121b of the first base 121 are substantially flush with each other.
[0119] As a result, in another embodiment 11, similar to the above-described another embodiment 10, the first member 124 faces the flow path 123. Also, in another embodiment 11, similar to the above-described another embodiment 10, the width W1 (see FIG. 15) of the first member 124 is smaller than the width W2 (see FIG. 15) of the flow path 123.
[0120] Even with this configuration, the first member 124, which has low thermal conductivity, is located on the path of heat H1 (see FIG. 5), which has a short transmission path, so that the transmission efficiency of heat H2 (see FIG. 5), which has a long transmission path, and the transmission efficiency of heat H1 can be made equal. Therefore, according to another embodiment 11, the in-plane temperature uniformity of the upper surface of the cooling member 120 can be improved.
[0121] In another embodiment 11, the first member 124 faces the flow path 123, so that the main path of heat transfer from the refrigerant flowing through the flow path 123 can be the side 123a of the flow path 123 rather than the top surface of the flow path 123 (i.e., the second surface 124b of the first member 124).
[0122] Therefore, according to the eleventh embodiment, the in-plane temperature uniformity of the upper surface of the cooling member 120 can be further improved.
[0123] <Another embodiment 12> Figure 17 is an enlarged cross-sectional view showing the configuration around the flow path 123 and the first member 124 of the sample holder 100 according to another embodiment 12. As shown in Figure 17, in the sample holder 100 according to another embodiment 12, the position of the first member 124 differs from that of the above-mentioned another embodiment 11 (see Figure 16).
[0124] Specifically, in another embodiment 12, the first member 124 is located inside the cooling member 120 so as to be embedded inside the first base 121. Note that in another embodiment 12, similar to the above-described another embodiment 11, the width W1 (see FIG. 15) of the first member 124 is smaller than the width W2 (see FIG. 15) of the flow path 123.
[0125] Even with this configuration, the first member 124, which has low thermal conductivity, is located on the path of heat H1 (see FIG. 5), which has a short transmission path, so that the transmission efficiency of heat H2 (see FIG. 5), which has a long transmission path, and the transmission efficiency of heat H1 can be made equal. Therefore, according to another embodiment 12, the in-plane temperature uniformity of the upper surface of the cooling member 120 can be improved.
[0126] Although the embodiments of the present disclosure have been described above, the present disclosure is not limited to the above embodiments, and various modifications are possible without departing from the spirit thereof. For example, in the above embodiments, examples have been shown in which the first base 121 and the second base 122 are each composed of a single member, but the present disclosure is not limited to such examples, and at least one of the first base 121 and the second base 122 may be composed of a combination of multiple members.
[0127] Additional advantages and other aspects 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.
[0128] The present technology can also be configured as follows. (1) A sample holder comprising: a ceramic substrate having a first surface on which a sample is held and a second surface opposite to the first surface; a cooling member bonded to the second surface of the ceramic substrate and having a flow path through which a refrigerant can flow; and a bonding material positioned between the ceramic substrate and the cooling member, wherein the cooling member comprises: a first base made of metal positioned closer to the ceramic substrate than the flow path; a second base made of metal positioned farther from the ceramic substrate than the first base and having a groove that becomes the flow path when bonded to the first base; and a first member positioned closer to the ceramic substrate than the flow path and having a thermal conductivity lower than that of the first base. (2) The sample holder according to (1), wherein the width of the first member is greater than the width of the flow path in a cross-sectional view. (3) The sample holder according to (1) or (2), wherein the first member faces the flow path. (4) The sample holder according to any one of (1) to (3), wherein the second surface of the first base that contacts the second base is flat. (5) The sample holder according to any one of (1) to (4), wherein the first member is rectangular. (6) The sample holder according to any one of (1) to (5), wherein the second base has a higher thermal conductivity than the first member. (7) The sample holder according to any one of (1) to (6), wherein the second base has a step at the opening of the groove. (8) The sample holder according to (7), wherein the first member is located at the step of the second base, and wherein the thickness of the first member is smaller than the height of the step. (9) The sample holder according to (7) or (8), wherein a plurality of resins are located to sandwich the corner of the first member located at the step. (10) The sample holder according to any one of (1) to (9), wherein a second member having a higher thermal conductivity than the first member and a lower thermal conductivity than the first base is located between a first surface of the first member facing the ceramic substrate and the first base. (11) The sample holder according to any one of (1) to (10), wherein a first region having a lower thermal conductivity than the first member is located between a side surface of the first member and the second base.(12) The sample holder according to (11), wherein a gap is located in the first region. (13) The sample holder according to (11) or (12), wherein a resin is located in the first region.
[0129] 100 Sample holder 110 Ceramic substrate 110a First surface 110b Second surface 120 Cooling member 121 First base 121a First surface 121b Second surface 122 Second base 122a First surface 122b Second surface 122c Groove 122d Step portion 123 Channel 124 First member 124a First surface 124b Second surface 124c Side surface 124d Corner 125 Second member 126 Resin A First region L1 Thickness L2 Height W1, W2 Width
Claims
1. A ceramic substrate having a first surface on which a sample is held and a second surface opposite to the first surface, A cooling member bonded to the second surface of the ceramic substrate, having a flow path through which a refrigerant can pass, A bonding material located between the ceramic substrate and the cooling member, Equipped with, The cooling member comprises a first metal base located on the ceramic substrate side of the flow path, A second metal substrate is positioned further away from the ceramic substrate than the first substrate, and is joined to the first substrate to form grooves that serve as flow channels. A first member located on the ceramic substrate side with respect to the flow path and having a lower thermal conductivity than the first substrate, A sample holder having the following features.
2. In a cross-sectional view, the width of the first member is greater than the width of the flow path. The sample holder according to claim 1.
3. The first member is facing the flow path. The sample holder according to claim 2.
4. In the first substrate, the second surface in contact with the second substrate is a plane. The sample holder according to claim 3.
5. The first member is rectangular in shape. A sample holder according to any one of claims 1 to 4.
6. The second substrate has a higher thermal conductivity than the first member. A sample holder according to any one of claims 1 to 4.
7. The second substrate has a stepped portion at the opening of the groove. The sample holder according to claim 6.
8. The first member is located at the stepped portion of the second base, The thickness of the first member is smaller than the height of the stepped portion. The sample holder according to claim 7.
9. Multiple resins are positioned so as to sandwich the corner of the first member located at the stepped portion. The sample holder according to claim 7.
10. Between the first surface of the first member on the ceramic substrate side and the first base body, a second member is positioned which has a higher thermal conductivity than the first member and a lower thermal conductivity than the first base body. A sample holder according to any one of claims 1 to 4.
11. Between the side surface of the first member and the second substrate, there is a first region having a lower thermal conductivity than the first member. A sample holder according to any one of claims 1 to 4.
12. A void is located in the first region. The sample holder according to claim 11.
13. The resin is located in the first region. The sample holder according to claim 11.