Ceramic wiring member

Abstract

A ceramic wiring member (1) is provided with: a ceramic main body section (10) having plate-shaped sections (11, 12); and a conductive part (20) disposed so as to be in contact with the plate-shaped parts (11, 12). The structure of the conductive part (20) includes: a conductive phase (31) having a metal component including W and / or Mo, and having a plurality of voids (31A) dispersed apart from each other; and a glass phase (32) filling the plurality of voids (31A) and having an area ratio of 3% to 20% in a cross-section in the thickness direction of the plate-shaped parts (11, 12). In a cross-section in the thickness direction of the plate-shaped sections (11, 12), the proportion of the number of glass phases (32) having an aspect ratio of 1.5 or less relative to the total number of glass phases (32) is 40% or more.

Description

Technical Field

[0001] The present disclosure relates to a ceramic wiring member. Background Art

[0002] A ceramic wiring component is known, comprising: a main body portion made of ceramic, which has a plate-like portion; and a conductive portion, which is arranged in contact with the plate-like portion and is composed of a material including metal. Such a ceramic wiring component is used as a component for holding electronic components. The conductive portion constitutes a part of a current path for current to flow into or out of the electronic component. In such a ceramic wiring component, it is important to reduce the resistance of the conductive portion. On the other hand, due to the difference in linear expansion coefficient between the ceramic constituting the main body portion and the metal constituting the conductive portion, warping sometimes occurs in the ceramic wiring substrate. If the warping becomes larger, there is a possibility that the conductive portion peels off from the main body portion and other undesirable conditions may occur. Therefore, it is desired to reduce the warping.

[0003] For example, by introducing a ceramic glass phase into the conductive part so that the linear expansion coefficient of the conductive part is close to the linear expansion coefficient of the main body, the above-mentioned warping can be reduced. It is known that the glass phase in the ceramic constituting the main body is formed in the conductive part during the manufacturing process of the ceramic wiring member, and the glass phase is composed of components added mainly as a sintering aid (for example, refer to Japanese Patent Publication No. 2003-347710 (Patent Document 1)). It can be considered that although the resistance of the conductive part increases due to the formation of the glass phase, the increase in resistance can be kept within an allowable range and the warping can be reduced by forming an appropriate amount of the glass phase. Prior art literature Patent Literature

[0004] Patent Document 1: Japanese Patent Application Publication No. 2003-347710 Summary of the invention Problems to be solved by the invention

[0005] However, even when the ratio of the glass phase in the conductive portion is within an appropriate range as described above, the electrical resistance may increase beyond the allowable range, and the warpage may not be sufficiently reduced.

[0006] One of the objects of the present disclosure is to provide a ceramic wiring member capable of achieving both reduction in warpage and reduction in the electrical resistance of a conductive portion. Solutions to Solve Problems

[0007] The ceramic wiring component disclosed in the present invention comprises: a main body portion made of ceramic, which has a plate-like portion; and a conductive portion, which is arranged in contact with the plate-like portion. The structure of the conductive portion includes: a conductive phase, which has a metal component and has a plurality of voids dispersed separately from each other, and the metal component includes at least one of W (tungsten) and Mo (molybdenum); and a glass phase, which fills the above-mentioned plurality of voids, and the area ratio in the cross-section in the thickness direction of the plate-like portion is greater than 3% and less than 20%. In the cross-section in the thickness direction of the plate-like portion, the ratio of the number of glass phases with an aspect ratio (aspect ratio) of less than 1.5 in the total number of glass phases is greater than 40%. Effects of the Invention

[0008] According to the ceramic wiring member described above, it is possible to provide a ceramic wiring member capable of achieving both reduction in warpage and reduction in the electrical resistance of the conductive portion. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1 It is a schematic cross-sectional view showing the structure of a ceramic wiring member. Figure 2 It is a schematic cross-sectional view showing the structure near the interface between the main body portion (plate-shaped portion) and the conductive portion. Figure 3 This is a flowchart schematically showing a method for manufacturing a ceramic wiring member. Figure 4 This is a schematic cross-sectional view showing the structure of a ceramic wiring member in the second embodiment. Figure 5 This is a schematic cross-sectional view showing the structure of a ceramic wiring member in the third embodiment. Figure 6 This is a diagram for explaining the analysis of the existence state of the glass phase in the conductive portion. DETAILED DESCRIPTION

[0010] [Overview of Embodiments] First, the embodiments of the present disclosure are listed for explanation. The ceramic wiring component of the first aspect of the present disclosure comprises: a main body portion made of ceramic, which has a plate-like portion; and a conductive portion, which is arranged in contact with the plate-like portion. The structure of the conductive portion includes: a conductive phase, which has a metal component and has a plurality of voids dispersed separately from each other, and the metal component includes at least one of W and Mo; and a glass phase, which fills the plurality of voids, and the area ratio in the cross section in the thickness direction of the plate-like portion is greater than 3% and less than 20%. In the cross section in the thickness direction of the plate-like portion, the ratio of the number of glass phases with an aspect ratio of less than 1.5 to the total number of glass phases is greater than 40%.

[0011] In the ceramic wiring member according to the first aspect, in a cross section in the thickness direction of the plate-like portion, the ratio of the number of glass phases having an aspect ratio of 2 or less to the total number of the glass phases may be 65% or more.

[0012] The present inventors have studied the reasons why the resistance increases beyond the allowable range or the warpage cannot be sufficiently reduced even when the ratio of the glass phase in the conductive portion is within an appropriate range. As a result, the inventors have obtained the following findings.

[0013] Regarding the above-mentioned resistance and warpage value, the shape of the glass phase filling the above-mentioned gap is affected. Specifically, when the shape of each glass phase is far from spherical, that is, when the aspect ratio of the glass phase in the cross section in the thickness direction of the plate-like portion is large, the influence on the increase of the resistance value and the warpage value is large. The reasons can be considered as follows. When the aspect ratio of the glass phase is large, stress concentration is likely to occur near the front end of the length direction of the glass phase. Therefore, in the manufacturing process of the ceramic wiring component after the main body and the conductive part are fired, if stress is applied to the conductive part, stress is concentrated near the above-mentioned front end, and tiny cracks are generated in the conductive phase. Due to the generation of this crack, the resistance of the conductive part increases. In addition, when the aspect ratio of the glass phase is large, the expansion amount differs between the major diameter direction and the minor diameter direction. Therefore, the glass phase will not shrink isotropically (or expand isotropically) in three dimensions. As a result, uneven stress is generated and the warpage value becomes larger.

[0014] In contrast, when the aspect ratio of the glass phase is close to 1, that is, when the shape of the glass phase is close to spherical, the presence of the glass phase has little effect on the increase in resistance value and warpage value. More specifically, in the cross-section in the thickness direction of the plate-like portion, the proportion of the number of glass phases with an aspect ratio of 1.5 or less in the total number of glass phases is 40% or more, preferably the proportion of the number of glass phases with an aspect ratio of 1.5 or less is 40% or more, and the proportion of the number of glass phases with an aspect ratio of 2 or less is 65% or more, thereby reducing the effect of the presence of the glass phase on the increase in resistance value and warpage value. As a result, according to the ceramic wiring component disclosed in the present invention, it is possible to provide a ceramic wiring component that can take into account both the reduction of warpage and the reduction of the resistance of the conductive portion.

[0015] Here, in the present application, the aspect ratio of the glass phase refers to the ratio of the major diameter to the minor diameter of the ellipse with the minimum area that includes each glass phase. For example, the aspect ratio can be obtained as follows: for the conductive portion, observe the cross-section in the thickness direction of the plate-like portion with a scanning electron microscope, perform black and white binarization on the obtained image data using image processing software, and then determine the ellipse with the minimum area that includes each glass phase, and calculate the ratio of the major diameter to the minor diameter of the ellipse (major diameter / minor diameter). Acquire data so that more than 150 glass phases are included in the image data. In addition, in the present application, the so-called glass phase refers to, in addition to the glass component included in the main body, a certain amount of crystals of the main ceramic component (aluminum oxide) included in the main body, and metal components in the conductive portion. In addition, the glass phase may also include glass components that are not included in the main body.

[0016] In the ceramic wiring member, the conductive portion may include a first portion in contact with a first main surface of the plate-like portion and a second portion in contact with a second main surface located on the opposite side of the first main surface in the thickness direction of the plate-like portion. In this way, the first main surface side and the second main surface side of the plate-like portion are electrically connected by the conductive portion with reduced resistance, thereby obtaining a high-performance ceramic wiring member that can cope with power saving and increased communication speed.

[0017] [Specific example of embodiment] Next, specific embodiments of the ceramic wiring member of the present disclosure will be described with reference to the drawings. In the following drawings, the same or corresponding parts are denoted by the same reference numerals, and their description will not be repeated.

[0018] (Implementation Method 1) Figure 1 2 is a schematic cross-sectional view showing the structure of a ceramic wiring member in one embodiment of the present disclosure. Figure 1 The ceramic wiring member 1 of the present embodiment includes a main body 10 made of ceramic and a conductive portion 20. The ceramic constituting the main body 10 is not particularly limited, and for example, alumina (Al 2 O 3 ). In addition, the ceramic constituting the main body 10 may also include a glass component as a sintering aid, and the glass component is selected from at least one of an oxide including Si, an oxide including Ca, an oxide including Mg, an oxide including Mn, and an oxide including Ba.

[0019] The main body 10 includes: a bottom wall portion 11 having a plate-like shape as a first plate-like portion; and a side wall portion 12 having a plate-like shape as a second plate-like portion. The bottom wall portion 11 has a flat plate-like shape. The bottom wall portion 11 includes a first main surface 11A and a second main surface 11B located on the opposite side of the first main surface 11A in the thickness direction. The planar shape of the bottom wall portion 11 (the shape observed in a direction perpendicular to the first main surface 11A) is, for example, a rectangle.

[0020] The side wall portion 12 has a plate-like shape rising from the outer edge of the first main surface 11A of the bottom wall portion 11. More specifically, it has a shape formed by connecting four flat plates corresponding to the respective sides of the outer edge of the first main surface 11A of the bottom wall portion 11 having a rectangular planar shape. When viewed in a direction perpendicular to the first main surface 11A, the side wall portion 12 may be configured, for example, to surround the space on the first main surface 11A, i.e., the cavity 10A. The side wall portion 12 includes a planar first end surface 12A and a planar end surface, i.e., a second end surface 12B, on the side opposite to the first end surface 12A in the thickness direction of the bottom wall portion 11. The side wall portion 12 is connected to the first main surface 11A of the bottom wall portion 11 at the second end surface 12B. The first end surface 12A is located on a single plane throughout the entire area. As a result, the cavity 10A can be closed by placing a flat cover member on the first end surface 12A. Electronic components such as crystal oscillators that require airtightness can be accommodated in the cavity 10A. Such a ceramic wiring member 1 is used as a ceramic package.

[0021] In the present embodiment, the ceramic wiring member 1 includes a pair of conductive parts 20. Each conductive part 20 includes: an internal terminal 21 as a first part, which is arranged in contact with the first main surface 11A; an external terminal 25 as a second part, which is arranged in contact with the second main surface 11B; and an internal wiring 23 arranged inside the bottom wall part 11. Each conductive part 20 also includes: a first connecting part 22 that connects the internal terminal 21 and the internal wiring 23; and a second connecting part 24 that connects the internal wiring 23 and the external terminal 25. The internal wiring 23, the first connecting part 22, and the second connecting part 24 are the third parts that connect the internal terminal 21 as the first part and the external terminal 25 as the second part. The internal terminal 21, the external terminal 25, the internal wiring 23, the first connecting part 22, and the second connecting part 24 are all parts of the conductive part 20 that are arranged in contact with the bottom wall part 11 as the first plate-shaped part. As a modification of the first connection portion 22 and the second connection portion 24 , for example, a castellation structure may be provided on the side surface of the bottom wall portion 11 , and a conductive portion may be provided on the surface of the castellation structure.

[0022] Reference Figure 2The structure of at least one of the internal terminal 21, the external terminal 25, the internal wiring 23, the first connection part 22 and the second connection part 24 constituting the conductive part 20, preferably all the structures include: a conductive phase 31 having a metal component and having a plurality of voids 31A dispersed separately from each other, the metal component including at least one of W and Mo; and a glass phase 32 filling the plurality of voids 31A, and the area ratio in the cross section in the thickness direction of the bottom wall part 11 is 3% or more and 20% or less. By making the area ratio of the glass phase 20% or less, the increase in the resistance of the conductive part 20 can be suppressed, and by making the area ratio of the glass phase 3% or more, preferably 8% or more, the difference in the linear expansion coefficient between the conductive part 20 and the main body 10 can be reduced. The glass phase 32 in the conductive part 20 basically intrudes from the main body by capillary phenomenon during sintering, but the glass phase 32 may also include a glass component not contained in the main body 10. From the viewpoint of electrical resistance and strength, the area ratio of the voids 31A not filled with the glass phase 32 in the cross section of the conductive portion 20 is preferably 5% or less, and more preferably 1% or less. Figure 2 In the cross section shown in FIG. 1 , the ratio of the number of glass phases 32 having an aspect ratio of 1.5 or less in the total number of glass phases 32 is 40% or more. It should be noted that, with respect to the glass phase 32, the major diameter of the ellipse obtained by the ellipse fitting described later is preferably 0.1 μm or more and 4 μm or less. By setting the major diameter of the ellipse to be 0.1 μm or more, the voids 31A in the conductive portion 20 can be suppressed, and the strength of the conductive portion 20 can be increased. In addition, by setting the major diameter of the ellipse to be 4 μm or less, the resistance of the conductive portion 20 can be reduced.

[0023] In the ceramic wiring member 1 of the present embodiment, in the cross section in the thickness direction of the bottom wall portion 11 as the plate-like portion, the ratio of the number of glass phases 32 having an aspect ratio of 1.5 or less in the total number of glass phases 32 is 40% or more. As a result, the presence of the glass phase 32 reduces the influence of the increase in the resistance value and the warpage value of the conductive portion 20. As a result, the ceramic wiring member 1 of the present embodiment is a ceramic wiring member that achieves both reduction in warpage and reduction in the resistance of the conductive portion 20.

[0024] In the ceramic wiring member 1 of the present embodiment described above, it is preferred that the ratio of the number of glass phases having an aspect ratio of 2 or less to the total number of glass phases 32 is 65% or more. As a result, the influence of the presence of the glass phase 32 on the increase in the resistance value and the warpage value of the conductive portion 20 is more reliably reduced. As a result, the ceramic wiring member 1 of the present embodiment can be a ceramic wiring member that more reliably achieves both reduction in warpage and reduction in the resistance of the conductive portion 20.

[0025] Next, an example of a method for manufacturing ceramic wiring member 1 in the present embodiment will be described. Figure 3 1 is a flowchart schematically showing a method for manufacturing a ceramic wiring member. Figure 3 In the manufacturing method of the ceramic wiring member 1 of the present embodiment, first, as step S10, a green sheet preparation step is performed. In this step S10, a green sheet to be the main body 10 is prepared. Specifically, Al, which is the main component of the ceramic powder constituting the main body 10, is milled by a ball mill. 2 O 3 , sintering aid powder, and resin, solvent, etc. that do not constitute the main body 10 (i.e., disappear during firing) are mixed to obtain a slurry. The slurry is processed into a green sheet by a doctor blade method. Thus, a green sheet to become the main body 10 is obtained. Here, refer to Figure 1 As the green sheet to be the bottom wall portion 11, a plurality of green sheets having a rectangular planar shape are prepared. In addition, a plurality of green sheets to be the side wall portion 12 are also prepared. As the green sheet to be the side wall portion 12, a ring-shaped green sheet having a rectangular planar shape and from which a portion (central portion) corresponding to the cavity 10A is removed is prepared.

[0026] Next, as step S20, a conductive portion printing step is implemented. In this step S20, a paste to be the conductive portion 20 is printed on the green sheet prepared in step S10. Specifically, firstly, a first metal component, a second metal component, and additives, resins, solvents, etc. are combined, and then ceramic powder is added as needed and mixed to prepare a paste, wherein the first metal component is at least one of W and Mo, and the second metal component is selected from at least one of Ni, Co, and Fe. The ceramic powder may be the same as the ceramic powder constituting the main body 10, or may be different.

[0027] For example, the paste is printed on the green sheet prepared in step S10 by screen printing. Figure 1 As the green sheet to be the bottom wall portion 11, a green sheet having the above-mentioned paste printed on the region corresponding to the external terminal 25, a green sheet having the above-mentioned paste printed on the region corresponding to the second connection portion 24, a green sheet having the above-mentioned paste printed on the region corresponding to the internal wiring 23, a green sheet having the above-mentioned paste printed on the region corresponding to the first connection portion 22, and a green sheet having the above-mentioned paste printed on the region corresponding to the internal terminal 21 are prepared, and these green sheets are dried and stacked in sequence. Drying can be performed, for example, under the condition of heating to 110° C. and maintaining for 5 minutes.

[0028] Furthermore, a plurality of green sheets to be the side wall portion 12 prepared in step S10 (ring-shaped green sheets from which portions corresponding to the cavity 10A are removed) are further stacked. In this way, a stack of green sheets is obtained.

[0029] Next, as step S30, a firing step is performed. In this step, the stack of green sheets prepared in step S20 is fired. Firing can be performed, for example, by heating to a temperature of 800° C. or higher and 1600° C. or lower in an atmosphere mixed with hydrogen, nitrogen, and water vapor. In consideration of sufficient sintering, the heating temperature is selected from a temperature range that can suppress the formation of an intermetallic compound phase composed of an intermetallic compound of the first metal component and the second metal component in the structure of the conductive portion 20. Through the above steps, the ceramic wiring member 1 of the present embodiment can be manufactured.

[0030] In the manufacturing method of the ceramic wiring member 1 of the present embodiment, in step S20, in addition to the first metal component, a second metal component is used as a metal component constituting the conductive phase 31. The second metal component is added at a ratio of 0.1% or more and 10% or less relative to the first metal component. The remaining metal components other than the first metal component and the second metal component are only inevitable impurities. By adding the second metal component, it is possible to suppress the glass phase including the sintering aid constituting the main body 10 from invading the conductive portion 20 in step S30. In addition, by adding the second metal component, the sintering of the metal powder as the raw material powder of the conductive portion 20 can be promoted. As a result, the glass phases 32 filling the adjacent gaps 31A are suppressed from being connected to each other, and the aspect ratio of the glass phase 32 becomes smaller. The manufacturing method of the ceramic wiring member 1 of the present embodiment is not limited to the above-mentioned manufacturing method, but the ceramic wiring member 1 of the present embodiment can be easily manufactured by the above-mentioned manufacturing method.

[0031] (Implementation Method 2) Next, Embodiment 2 which is another embodiment of the present disclosure will be described. Figure 4 This is a schematic cross-sectional view showing the structure of a ceramic wiring member in the second embodiment. Figure 4 The same as that referred to in the description of Implementation 1 Figure 1 Corresponding figure. Figure 4 and Figure 1 The ceramic wiring member 1 of the second embodiment basically has the same structure as that of the first embodiment and achieves the same effect. However, the ceramic wiring member 1 of the second embodiment mainly differs from that of the first embodiment in the arrangement and structure of the conductive portion. Hereinafter, the second embodiment will be described with the differences from the first embodiment as the center.

[0032] Reference Figure 4The conductive portion 20 of the ceramic wiring member 1 of the second embodiment includes an upper terminal 26 as a first portion arranged in contact with the first end surface 12A, a lower terminal 28 as a second portion arranged in contact with the second end surface 12B, and a third connecting portion 27 connecting the upper terminal 26 and the lower terminal 28. The lower terminal 28 is arranged so as to also be in contact with the first main surface 11A of the bottom wall portion 11. The upper terminal 26, the lower terminal 28, and the third connecting portion 27 are all parts of the conductive portion 20 arranged in contact with the side wall portion 12 as the second plate-shaped portion.

[0033] The composition of at least one of the upper terminal 26, the lower terminal 28, and the third connecting portion 27 constituting the conductive portion 20, preferably all of the compositions, similarly to the internal terminal 21 of the first embodiment, includes: a first metal component, which is at least one of W and Mo as a main component; and a second metal component, which is 0.1% or more and 10% or less in total relative to the first metal component, and is selected from at least one of Ni, Co, and Fe. Furthermore, the above-mentioned at least one of the structures of the upper terminal 26, the lower terminal 28, and the third connecting portion 27 constituting the conductive portion 20, preferably all of the structures, similarly to the internal terminal 21 of the first embodiment, includes a conductive phase including an alloy of the first metal component and the second metal component. Furthermore, the above-mentioned at least one of the structures of the upper terminal 26, the lower terminal 28, and the third connecting portion 27 constituting the conductive portion 20, preferably all of the structures, includes a glass phase 32 including a ceramic component having an area ratio of 3% or more and 20% or less in the cross section of the conductive portion 20.

[0034] The ceramic wiring member 1 of the present embodiment can also obtain the same effects as those of the case of the first embodiment. In addition, the ceramic wiring member 1 of the present embodiment can be manufactured in the same manner as that of the case of the first embodiment except that the arrangement of the conductive portion 20 is mainly changed. It should be noted that in the present embodiment, the bottom wall portion 11 is made of ceramic as an insulator, but a conductor such as metal may be used as a material constituting the bottom wall portion 11.

[0035] (Implementation 3) Next, Embodiment 3 which is still another embodiment of the present disclosure will be described. Figure 5 This is a schematic cross-sectional view showing the structure of a ceramic wiring member in the third embodiment. Figure 5 The same as that referred to in the description of Implementation 1 Figure 1 Corresponding figure. Figure 5 and Figure 1The ceramic wiring member 1 of the third embodiment basically has the same structure as the first embodiment and has the same effect. However, the ceramic wiring member 1 of the third embodiment mainly differs from the first embodiment in the structure of the main body, the arrangement and structure of the conductive portion. Hereinafter, the third embodiment will be described with the differences from the first embodiment as the center.

[0036] Reference Figure 5 The side wall portion 12 of the ceramic wiring member 1 of the third embodiment includes a protrusion 121 that protrudes toward the area opposite to each other across the cavity 10A. The protrusion 121 includes: a first surface 121B that is opposite to the first main surface 11A of the bottom wall portion 11; a second surface 121A that is located on the side opposite to the first surface 121B in the thickness direction of the bottom wall portion 11; and a third surface 121C that is a front end surface connecting the first surface 121B and the second surface 121A. The area of ​​the first surface 121B including the front end connected to the third surface 121C is opposite to the first main surface 11A, and the other area (the area corresponding to the vicinity of the root of the protrusion 121) is not opposite to the first main surface 11A.

[0037] The conductive portion 20 includes an upper terminal 26 as a first portion, which is arranged in contact with the first end surface 12A; a lower terminal 28 as a second portion, which is arranged in contact with the second end surface 12B; and a third connecting portion 27 that connects the upper terminal 26 and the lower terminal 28. The conductive portion 20 also includes an intermediate terminal 30 that is arranged in contact with the first surface 121B; and a fourth connecting portion 29 that connects the intermediate terminal 30 and the third connecting portion 27. The intermediate terminal 30 is arranged in contact with the first main surface 11A of the bottom wall portion 11. The upper terminal 26, the lower terminal 28, the third connecting portion 27, the intermediate terminal 30, and the fourth connecting portion 29 are all parts of the conductive portion 20 that are arranged in contact with the side wall portion 12.

[0038] The composition of at least one of the upper terminal 26, the lower terminal 28, the third connecting portion 27, the intermediate terminal 30, and the fourth connecting portion 29 constituting the conductive portion 20, preferably all of the compositions, similarly to the internal terminal 21 of the first embodiment, includes: a first metal component, which is at least one of W and Mo as a main component; and a second metal component, which is 0.1% or more and 10% or less in total relative to the first metal component, and is selected from at least one of Ni, Co, and Fe. Furthermore, the above-mentioned at least one of the structures of the upper terminal 26, the lower terminal 28, and the third connecting portion 27 constituting the conductive portion 20, preferably all of the structures, similarly to the internal terminal 21 of the first embodiment, includes a conductive phase, and the conductive phase includes an alloy of the first metal component and the second metal component. It should be noted that the alloy here refers to a mixture of the first metal component and the second metal component that are not dissolved in a solid solution in addition to the solid solution of the first metal component and the second metal component. Furthermore, the structure of at least one of the upper terminal 26, the lower terminal 28, the third connecting part 27, the intermediate terminal 30 and the fourth connecting part 29 constituting the conductive part 20, and preferably all of the structures includes a glass phase 32, which includes a ceramic component with an area ratio of more than 3% and less than 20% in the cross section of the conductive part 20.

[0039] In the ceramic wiring component 1 of the present embodiment, the same effects as those in the case of the first embodiment can also be obtained. In addition, the ceramic wiring component 1 of the present embodiment can be manufactured in the same manner as the case of the first embodiment, except that the structure of the main body 10 and the arrangement of the conductive portion 20 are mainly changed. It should be noted that in the present embodiment, the bottom wall 11 is made of ceramic as an insulator, but a conductor such as metal can also be used as a material constituting the bottom wall 11. In addition, in the above-mentioned embodiment, the shape of the main body 10 is illustrated, but the shape of the main body of the present disclosure is not limited thereto. As the shape of the main body, various shapes such as a rectangular parallelepiped shape, a spherical shape, and a film shape can be adopted. Example

[0040] An experiment was conducted to investigate the influence of the area ratio and aspect ratio of the glass phase on the resistivity of the conductive portion, the warpage of the ceramic wiring member, and the adhesion strength of the conductive portion to the main body portion. The experimental procedure is as follows.

[0041] The conductive portion 20 disposed in contact with the main body 10 was formed by the same steps as the manufacturing method described in the above embodiment, and the resistivity of the conductive portion 20, the warpage of the ceramic wiring member 1, and the adhesion strength of the conductive portion 20 to the main body 10 were investigated. Specifically, in step S10, a green sheet including Al 2 O 3 powder, selected from SiO 2, at least one powder of CaO, MgO, MnO and BaO, a resin, a solvent, etc.

[0042] Next, in step S20, a paste including a first metal component is printed on the green sheet prepared in step S10 and dried. No ceramic component is added to the paste. Drying is carried out under the condition of heating to 110° C. and maintaining for 5 minutes. At this time, at least one of W and Mo is used as the first metal component. In addition, from the viewpoint of changing the area ratio and aspect ratio of the glass phase, the addition amount of Ni, Co, and Fe as the second metal component is changed. In addition, a sample without adding the second metal component was also produced.

[0043] Then, in step S30, the green sheet printed with the paste is fired. The firing is performed by heating from room temperature to a predetermined temperature in an atmosphere mixed with hydrogen, nitrogen and water vapor, and then cooling to room temperature. As a result, a sample having a conductive portion arranged on one main surface of a ceramic main body having a plate-like portion is obtained. It should be noted that in this sample, a conductive portion and internal wiring are not implemented on the other main surface. Regarding the conductive portion after firing, the voids not filled with the glass phase are less than 1% in terms of area ratio.

[0044] For the obtained sample, the area ratio of the glass phase in the conductive part in the cross section in the thickness direction of the plate-like part, the ratio of the number of glass phases with an aspect ratio of less than 1.5 in the total number of glass phases, and the ratio of the number of glass phases with an aspect ratio of less than 2 are investigated. Specifically, for the obtained sample, the cross section of the conductive part 20 is observed with a scanning electron microscope. Then, for the obtained image data, after black and white binarization using image processing software, the area of ​​the glass phase 32 is totaled, and the area ratio of the glass phase 32 in the conductive part 20 is calculated. In addition, the ellipse with the minimum area including each glass phase is determined (ellipse fitting), and the ratio of the major diameter of the ellipse to the minor diameter (major diameter / minor diameter) is calculated, thereby obtaining the aspect ratio of each glass phase. Then, based on the aspect ratio of each glass phase obtained, the number of glass phases with an aspect ratio of less than 1.5 is calculated. Based on the results, the ratio of the number of glass phases with an aspect ratio of 1.5 or less to the total number of glass phases and the ratio of the number of glass phases with an aspect ratio of 2 or less to the total number of glass phases in the field of view observed by scanning electron microscopy were calculated. ImageJ (free software) was used for the above image processing.

[0045] Furthermore, for the obtained sample, the resistivity of the conductive portion 20 was investigated. Specifically, for the obtained sample, the resistance of the conductive portion 20 was first measured by a four-terminal method. The resistance was measured using RM3544-01 manufactured by Hioki Electric Co., Ltd. Then, the resistivity was calculated from the obtained resistance and the length of the conductive portion 20 and the cross-sectional area perpendicular to the length direction.

[0046] In addition, the warpage of the obtained sample was measured. Specifically, the warpage value of the sample was investigated using a three-dimensional shape measuring device (model VK-X1000) manufactured by KEYENCE Co., Ltd. When the sample was set on a plane in a manner such that one main surface with a conductive portion was on top and the other main surface was on the bottom, the warpage value was measured by setting the state of convexity to one main surface side as negative and the state of convexity to the other main surface side as positive.

[0047] Furthermore, for the obtained sample, the adhesion strength of the conductive part 20 relative to the main body 10 was investigated. Specifically, a Ni plating layer with a thickness of 2μm to 3μm was applied to the conductive part with a width of 2mm and a length of 5mm, and a 5mm portion of a length of a metal L-shaped holding member with a width of 0.7mm, a length of 5mm, and a height of 2.5mm in a direction perpendicular to the length direction was joined by brazing. Then, the holding member and the sample were held separately, and the front end portion of the holding member with a height of 2.5mm was pulled in a direction perpendicular to the interface between the conductive part and the main body, and the load at the moment when the conductive part was peeled off from the main body was measured as the adhesion strength. The measurement used a digital dynamometer (model ZP200N) manufactured by IMADA Co., Ltd. If the adhesion strength is 9.8N (1kgf) or more, it can be judged as sufficient, and if it is less than 9.8N, it can be judged as insufficient. The above experimental results are shown in Table 1.

[0048] [Table 1] In Table 1, regarding resistivity, less than 0.15Ω·μm is evaluated as A, 0.15Ω·μm or more and less than 0.2Ω·μm is evaluated as B, and 0.2Ω·μm or more is evaluated as C. Regarding warpage, an absolute value of less than 30μm is evaluated as A, and 30μm or more is evaluated as C. Regarding adhesion strength, 9.8N or more is evaluated as A, and less than 9.8N is evaluated as C. Regarding comprehensive judgment, samples that are evaluated as C in at least one of the above three evaluation items are evaluated as C, and samples that are not evaluated as C are evaluated as A. That is, A means excellent, C means poor, and B means in between. In addition, Figure 6 An example of analyzing the existence state of the glass phase 32 in the conductive portion 20 using image processing software is shown.

[0049] Figure 6: shows secondary electron images of the cross section near the interface between the conductive portion 20 and the main body 10 of Sample 5 and Sample 2, a binarized secondary electron image of the conductive portion 20 , and an ellipse fitting based on the binarized image. Figure 6 The left column shows the photographs (secondary electron images) of the cross-sections of each sample, the central column shows the results obtained by binarizing the secondary electron images of the cross-sections of the conductive portion, and the right column shows the results obtained by ellipse fitting the binarized results. The white area of ​​the secondary electron image is the metal component (W), and the black area is the glass phase. The black area of ​​the binarization result is the glass phase. The area surrounded by black lines in the ellipse fitting result is the glass phase.

[0050] Reference Figure 6 It can be seen that the area ratio of the glass phase in sample 5 is smaller than that in sample 2, and the ratio of the glass phase 32 with a small aspect ratio is higher. Based on such image data, the image data of the conductive portion 20 is binarized and ellipse fitting is performed to calculate the area ratio and aspect ratio of the glass phase 32.

[0051] Referring to Table 1, in Sample 1, the area ratio of the glass phase is outside the range of the present disclosure, that is, greater than 3% and less than 20%. Specifically, the area ratio of the glass phase is greater than 20%. As a result, the resistivity is greater than 0.2Ω·μm, and from the perspective of resistance, Sample 1 cannot be said to be ideal. In Samples 2 and 3, the area ratio of the glass phase 32 becomes smaller than that of Sample 1. As a result, the resistivity is less than 0.15Ω·μm, which can be said to be an ideal state from the perspective of resistance. However, the ratio of the number of glass phases with an aspect ratio of less than 1.5 and the ratio of the number of glass phases with an aspect ratio of less than 2 in the total number of glass phases are less than 40% and less than 65%, respectively. As a result, the absolute value of the warpage value is greater than 30μm, and from the perspective of warpage, Samples 2 and 3 cannot be said to be ideal.

[0052] In contrast, in samples 4 to 12, the area ratio of the glass phase 32 is within the range disclosed in the present disclosure, i.e., 3% to 20%, and the ratio of the number of glass phases 32 with an aspect ratio of 1.5 or less in the total number of glass phases 32 and the ratio of the number of glass phases 32 with an aspect ratio of 2 or less are 40% to 65% or more, respectively. As a result, these samples were judged as A or B in all items of resistivity, warpage, and adhesion strength, and it can be said that ideal characteristics were obtained. In particular, for samples with an area ratio of the glass phase 32 of 8% to 20%, since the adhesion strength was 19.6N (2kgf) or more, it can be said that more ideal characteristics were obtained.

[0053] In sample 13, the area ratio of the glass phase is outside the range of the present disclosure, that is, the range of more than 3% and less than 20%. Specifically, the area ratio of the glass phase is less than 3%. As a result, the adhesion strength is less than 9.8N (less than 1kgf), and from the perspective of the adhesion strength of the conductive part 20 to the main body 10, it cannot be said that sample 13 is ideal. It can be confirmed that the formation of the glass phase 32 derived from the sintering aid in the main body 10 contributes to the increase in the adhesion strength of the conductive part 20 to the main body 10. If the glass phase 32 is reduced to a level below the lower limit of the range disclosed in the present disclosure, the adhesion strength becomes insufficient.

[0054] In addition, in samples 14 to 16, Mo is used as the first metal component instead of W in samples 1 to 13. According to these experimental results, even when Mo is used as the first metal component, the same tendency as when W is used is confirmed.

[0055] From the above experimental results, it was confirmed that according to the ceramic wiring member of the present disclosure, it is possible to achieve both reduction in warpage and reduction in the resistance of the conductive portion.

[0056] It should be noted that, in the above-mentioned embodiment, the case where the main body 10 includes the side wall 12 is described, but the ceramic wiring member of the present disclosure is not limited to this, and may also include a flat main body 10 in which the side wall 12 is omitted. Such a ceramic wiring member is used as a ceramic wiring substrate for mounting electronic components. In addition, from the viewpoint of reducing contact resistance, a plating layer composed of a Ni (nickel) layer, an Au (gold) layer, etc. may also be formed on the surface of the internal terminal 21 and the external terminal 25.

[0057] It should be understood that the embodiments and examples disclosed this time are illustrative in all aspects and are not restrictive in any aspect. The scope of the present disclosure is not defined by the above description but by the claims, and is intended to include all changes within the meaning and scope equivalent to the claims. Explanation of symbols

[0058] 1 Ceramic wiring member, 10 Main body, 10A Cavity, 11 Bottom wall, 11A First main surface, 11B Second main surface, 12 Side wall, 12A First end surface, 12B Second end surface, 20 Conductive portion, 21 Internal terminal, 22 First connecting portion, 23 Internal wiring, 24 Second connecting portion, 25 External terminal, 26 Upper terminal, 27 Third connecting portion, 28 Lower terminal, 29 Fourth connecting portion, 30 Intermediate terminal, 31 Conductive phase, 31A Gap, 32 Glass phase, 121 Protrusion, 121A Second surface, 121B First surface, 121C Third surface.

Claims

1. A ceramic wiring member, wherein: The ceramic wiring member comprises: a main body made of ceramic, having a plate-shaped portion; and a conductive portion arranged in contact with the plate-shaped portion, The structure of the conductive part includes: a conductive phase having a metal component and having a plurality of voids dispersed separately from each other, the metal component including at least one of W and Mo; and a glass phase filling the plurality of voids and having an area ratio of 3% or more and 20% or less in a cross section in the thickness direction of the plate-like portion, In a cross section in the thickness direction of the plate-like portion, the ratio of the number of the glass phases having an aspect ratio of 1.5 or less to the total number of the glass phases is 40% or more.

2. The ceramic wiring member according to claim 1, wherein In a cross section in the thickness direction of the plate-like portion, the ratio of the number of the glass phases having an aspect ratio of 2 or less to the total number of the glass phases is 65% or more.

3. The ceramic wiring member according to claim 1 or 2, wherein The conductive part comprises: a first portion in contact with the first main surface of the plate-shaped portion; and The second portion is in contact with a second main surface located on the opposite side to the first main surface in the thickness direction of the plate-like portion.

Images