Ceramic substrate and electronic component

Abstract

This ceramic substrate (1) is provided with: an element body (10) including a ceramic layer; at least one internal conductor (40) provided inside the element body; and a terminal electrode (20) and an insulating layer (30) provided on the outer surface of the element body. The internal conductor and the terminal electrode are electrically connected. The terminal electrode has a first electrode (21) in contact with the outer surface of the element body, and a second electrode (22) covering the surface of the first electrode. At least a part of an outer edge portion (21e) of the first electrode and a part of the outer surface of the element body are covered with the insulating layer. In the thickness direction of the element body from the outer surface side of the element body, there are overlapped portions of the first electrode (21), the insulating layer (30), and the second electrode (22) in this order. The content of the non-conductive component in the first electrode (21) is 3-40 wt%, the content of the non-conductive component in the second electrode (22) is 0-10 wt%, and the content of the non-conductive component in the first electrode (21) is higher than or equal to the content of the non-conductive component in the second electrode (22).

Description

Ceramic substrates and electronic components

[0001] The present invention relates to a ceramic substrate and an electronic component.

[0002] Patent Document 1 discloses a ceramic laminate substrate having a plurality of ceramic layers and an electrode pattern, characterized in that the ceramic laminate substrate has a terminal electrode and an insulating layer on its outer surface, the terminal electrode has a base layer and an upper layer formed by an electrode pattern, at least a portion of the outer edge of the base layer and the ceramic layer are covered with the insulating layer, and at least a portion of the insulating layer is covered with the upper layer, thereby sandwiching the insulating layer between the upper layer and the base layer.

[0003] Japanese Patent Application Laid-Open No. 2005-209881

[0004] In the ceramic laminate substrate described in Patent Document 1, the base layer and upper layer of the terminal electrode are in close contact with the insulating layer. In this case, when tensile stress is applied to the terminal electrode due to thermal stress or the like, stress is likely to concentrate on the outer periphery of the terminal electrode. This may result in cracks occurring in the insulating layer directly below the outer periphery of the upper layer. If a crack occurs in the insulating layer from the edge of the upper layer, the base layer will stop the crack from progressing. However, because the base layer is thin directly below the insulating layer, the crack may not be sufficiently stopped from progressing. The crack may progress to an electrode provided inside the laminate substrate, causing a disruption of electrical continuity between the electrodes of the laminate substrate.

[0005] The present invention has been made to solve the above problems, and aims to provide a ceramic substrate that can ensure electrical continuity from terminal electrodes to internal conductors, and a further aim of the present invention is to provide an electronic component that includes the ceramic substrate.

[0006] The ceramic substrate of the present invention is a ceramic substrate comprising an element body including a ceramic layer, at least one internal conductor provided inside the element body, a terminal electrode provided on the outer surface of the element body, and an insulating layer provided on the outer surface of the element body, wherein the internal conductor and the terminal electrode are electrically connected, the terminal electrode has a first electrode in contact with the outer surface of the element body and a second electrode covering the surface of the first electrode, and the insulating layer covers at least a part of the outer edge of the first electrode and a part of the outer surface of the element body. The element body is coated with an insulating layer, and in a thickness direction perpendicular to the outer surface of the element body, there is a portion in which the first electrode, the insulating layer, and the second electrode are overlapped in this order from the outer surface side of the element body, the content of non-conductive components in the first electrode is 3% by weight or more and 40% by weight or less, the content of non-conductive components in the second electrode is 0% by weight or more and 10% by weight or less, and the content of the non-conductive components in the first electrode is the same as or higher than the content of the non-conductive components in the second electrode.

[0007] The electronic component of the present invention includes the ceramic substrate of the present invention.

[0008] According to the present invention, it is possible to provide a ceramic substrate that can ensure electrical continuity from terminal electrodes to internal conductors. Furthermore, according to the present invention, it is possible to provide an electronic component that includes the ceramic substrate.

[0009] FIG. 1 is a cross-sectional view schematically showing an example of a ceramic substrate of the present invention. FIG. 2 is a plan view schematically showing an example of a terminal electrode and an insulating layer. FIG. 3 is a cross-sectional view schematically showing how cracks form in the ceramic substrate of the present invention. FIG. 4 is a cross-sectional view schematically showing how cracks form in a ceramic substrate of a comparative example in which the adhesion between the second electrode and the insulating layer is strong. FIG. 5 is a cross-sectional view schematically showing how cracks form in a ceramic substrate of a comparative example in which the adhesion between the first electrode and the element body is weak. FIG. 6 is a cross-sectional view schematically showing how cracks form in a ceramic substrate of a comparative example in which the strength of the first electrode itself is low. FIG. 7 is a cross-sectional view schematically showing a process of forming a first conductive paste layer that will become the first electrode after firing. FIG. 8 is a plan view schematically showing a process of forming a first conductive paste layer that will become the first electrode after firing. FIG. 9 is a cross-sectional view schematically showing a process of forming an insulating paste layer that will become the insulating layer after firing. FIG. 10 is a plan view schematically showing a process of forming an insulating paste layer that will become the insulating layer after firing. FIG. 11 is a cross-sectional view schematically showing a process of forming a second conductive paste layer that will become a second electrode after firing. FIG. 12 is a plan view schematically showing a process of forming a second conductive paste layer that will become a second electrode after firing. FIG. 13 is a cross-sectional view schematically showing a first modified example of a ceramic substrate. FIG. 14 is a cross-sectional view schematically showing a second modified example of a ceramic substrate. FIG. 15 is a plan view schematically showing the second modified example of a ceramic substrate. FIG. 16 is a cross-sectional view schematically showing a third modified example of a ceramic substrate. FIG. 17 is a plan view schematically showing the third modified example of a ceramic substrate. FIG. 18 is a perspective view schematically showing an example of an electronic component of the present invention. FIG. 19 is a perspective view schematically showing an input / output terminal and a ground terminal in an example of an electronic component of the present invention. FIG. 20 is an exploded perspective view schematically showing an example of an electronic component of the present invention.

[0010] The ceramic substrate of the present invention will be described below. However, the present invention is not limited to the following configurations, and can be appropriately modified and applied within the scope of the present invention. Note that a combination of two or more of the individual desirable configurations described below also falls within the scope of the present invention.

[0011] FIG. 1 is a cross-sectional view schematically showing an example of the ceramic substrate of the present invention.

[0012] The ceramic substrate 1 comprises a base body 10 including a ceramic layer, at least one internal conductor 40 provided inside the base body 10, a terminal electrode 20 provided on the outer surface of the base body 10, and an insulating layer 30 provided on the outer surface of the base body 10.

[0013] The element body 10 includes ceramic layers. The element body 10 may be a multilayer ceramic substrate including a plurality of ceramic layers.

[0014] The material of the element body 10 is not particularly limited, but for example, a low-temperature co-fired ceramic (LTCC) material may be used. The low-temperature co-fired ceramic material is a ceramic material that can be sintered at a temperature of 1000°C or less and can be co-fired with Au, Ag, Cu, etc., which have low resistivity. Specific examples of the low-temperature co-fired ceramic material include glass composite low-temperature co-fired ceramic materials obtained by mixing ceramic powder such as alumina, zirconia, magnesia, spinel, forsterite, etc. with borosilicate glass; ZnO-MgO-Al ２ O ３ -SiO ２ Glass-ceramic low-temperature sintering ceramic material using BaO-Al ２ O ３ -SiO ２ Ceramic powder and Al ２ O ３ -CaO-SiO ２ -MgO-B ２ O ３ Examples of suitable materials include non-glass-based low-temperature sintered ceramic materials using ceramic powders.

[0015] The element body 10 may contain glass or may be a sintered body of glass ceramics. The type of glass is not particularly limited, but examples include borosilicate glass and crystallized glass.

[0016] Examples of materials for the element body 10 include: (1) MgAl ２ O ４ and Mg ２ SiO ４(2) a first ceramic comprising at least one of BaO, RE ２ O ３ (RE is a rare earth element) and TiO ２ (3) a second ceramic comprising 44.0 to 69.0 wt % of RO (R is at least one alkaline earth metal selected from Ba, Ca, and Sr), SiO ２ 14.2 to 30.0% by weight of B ２ O ３ 10.0 to 20.0 wt % of Al ２ O ３ 0.5 to 4.0% by weight, Li ２ and (4) MnO, wherein the glass ceramic composition contains 47.55 to 69.32 wt% of the first ceramic, 6 to 20 wt% of the glass, and 7.5 to 18.5 wt% of the MnO; and the second ceramic contains 0.38 to 1.43 wt% of BaO and 0.1 to 5.5 wt% of MgO. ２ O ３ 1.33 to 9.5 wt % and TiO ２ The glass ceramic composition may contain 0.95 to 6.75 wt % of each of these. The glass ceramic composition may contain 0.23 wt % or less of CuO. The glass ceramic composition may contain Mg ２ Al ４ Si ５ O 18 and BaAl ２ Si ２ O ８ The ceramic may contain 3 to 20 wt % of a third ceramic consisting of at least one of the above, and may further contain 0.3 wt % or less of CuO in addition to the third ceramic.

[0017] Another example of the material of the element body 10 is a glass ceramic containing glass containing Si, B, Al, and Zn, and an aggregate, the glass being 45% by weight or more and 80% by weight or less, and the aggregate being 20% ​​by weight or more and 50% by weight or less of SiO. ２ and 20 wt. % or less of Al ２ O ３and 10 wt % or less of ZnO. The glass ceramics contain SiO as a crystalline phase. ２ , ZnAl ２ O ４ , and Al ２ O ３ In the glass ceramics, the glass may contain SiO ２ The content of B is 15% by weight or more and 65% by weight or less, ２ O ３ The content of B is 11% by weight or more and 30% by weight or less, ２ O ３ SiO ２ Weight ratio (SiO ２ / B ２ O ３ ) is 1.21 or more, and Al to ZnO ２ O ３ Weight ratio (Al ２ O ３ In the glass ceramics, the glass may be a crystallized glass, and the crystalline phase ZnAl ２ O ４ In the glass ceramics, the glass may contain Li as a minor component. ２ O, and the glass contains Li ２ The content of O may be 1.0 wt % or less. In the glass ceramic, the crystallization temperature of the glass may be 1000°C or less. The relative dielectric constant of the glass ceramic may be 5 or less. In the glass ceramic, the contents of Si, B, Al, and Zn may be specified without distinguishing between glass and aggregate. Examples of materials in which the contents of Si, B, Al, and Zn are specified without distinguishing between glass and aggregate include glass ceramics containing Si, B, Al, and Zn, and SiO ２ The content is 52.00% by weight or more and 71.58% by weight or less, and B ２ O ３ The content is 6.30 wt% or more and 21.00 wt% or less, and Al ２ O ３The content is 7.63 wt% or more and 22.00 wt% or less, the ZnO content is 5.04 wt% or more and 17.00 wt% or less, and Li ２ Examples of glass-ceramics include glass-ceramics having an O content of 0.55 wt % or less. Table 1 shows examples of the ratio of each element in some glass-ceramics.

[0018]

[0019] The glass ceramics mentioned above include SiO ２ 60% by weight or more of B ２ O ３ 15% by weight or less, Al ２ O ３ It is preferable that the content of ZnO is 15% by weight or less and that of ZnO is 12% by weight or less. This makes it possible to make the relative dielectric constant 5 or less, and further 4.5 or less.

[0020] At least one internal conductor 40 is provided inside the element body 10. The internal conductor 40 and the terminal electrode 20 are electrically connected. The configuration of the internal conductor 40 is not particularly limited as long as it is a conductor that is electrically connected to the terminal electrode 20. One internal conductor 40 or multiple internal conductors 40 may be provided inside the element body 10. The material of the internal conductor 40 is not particularly limited, but may contain, for example, Cu or Ag as a conductive component.

[0021] 1 , the internal conductor 40 may include a via conductor 41 that is connected to the first electrode 21. In this case, the internal conductor 40 is electrically connected to the terminal electrode 20 through the via conductor 41.

[0022] 1 , a plurality of stacked conductor patterns may be connected in the internal conductor 40. In this case, the internal conductor 40 may include via conductors 42 that connect the plurality of stacked internal conductors together in addition to the via conductors 41 that connect to the first electrode 21. As will be described later, the ceramic substrate 1 may be used as an electronic component by forming an inductance element, a capacitance element, or the like using the internal conductors 40 provided inside the element body 10.

[0023] A terminal electrode 20 is provided on the outer surface of the element body 10. The terminal electrode 20 has a first electrode 21 that contacts the outer surface of the element body 10, and a second electrode 22 that covers the surface of the first electrode 21. Details of the first electrode 21 and the second electrode 22 will be described later.

[0024] An insulating layer 30 is provided on the outer surface of the element body 10. The insulating layer 30 covers at least a portion of the outer edge 21 e of the first electrode 21 and a portion of the outer surface of the element body 10. In the cross section shown in FIG. 1 , the insulating layer 30 covers the outer edge 21 e at both ends of the first electrode 21 and a portion of the outer surface of the element body 10. Furthermore, as shown in FIG. 1 , the insulating layer 30 may cover the entire portion of the outer surface of the first electrode 21 that is not covered by the second electrode 22. In other words, the entire outer surface of the first electrode 21 may be covered by the second electrode 22 or the insulating layer 30.

[0025] In the thickness direction (the vertical direction in FIG. 1 ) perpendicular to the outer surface of the element body 10, there is a portion (the portion indicated by the double-headed arrow w1 in FIGS. 1 and 2 ) where the first electrode 21, the insulating layer 30, and the second electrode 22 overlap in this order from the outer surface side of the element body 10. In FIG. 1 , the first electrode 21, the insulating layer 30, and the second electrode 22 overlap in this order from the outer surface side of the element body 10 over the entire portion where the insulating layer 30 covers the first electrode 21. In the portion where the first electrode 21, the insulating layer 30, and the second electrode 22 overlap in this order, the first electrode 21 and the second electrode 22 sandwich the insulating layer 30.

[0026] In a cross-sectional view of a portion where the first electrode 21, the insulating layer 30, and the second electrode 22 are stacked in this order from the outer surface side of the element body 10 in the thickness direction, the inner end 31 of the insulating layer 30 contacts the first electrode 21 and the second electrode 22. In other words, the inner end 31 of the insulating layer 30 is a point where the first electrode 21, the second electrode 22, and the insulating layer 30 contact each other.

[0027] FIG. 2 is a plan view schematically showing an example of a terminal electrode and an insulating layer.

[0028] Since the second electrode 22 exists above the first electrode 21, only the second electrode 22 of the terminal electrode 20 is visible in the plan view shown in Figure 2, but the first electrode 21 exists below the second electrode 22.

[0029] 2 , the insulating layer 30 may be provided over the entire outer edge 20 e of the terminal electrode 20. In other words, the insulating layer 30 may cover the entire outer edge 21 e of the first electrode 21. In the thickness direction perpendicular to the outer surface of the element body 10, a portion in which the first electrode 21, the insulating layer 30, and the second electrode 22 are superimposed in this order from the outer surface side of the element body 10 may exist over the entire outer edge 20 e of the terminal electrode 20.

[0030] The insulating layer 30 may be made of any insulating material, but may be made of a ceramic insulating layer, for example. The ceramic insulating layer may be made of the above-mentioned low-temperature co-fired ceramic material. Alternatively, the above-mentioned low-temperature co-fired ceramic material may be made of alumina (Al ２ O ３ A ceramic insulating layer can be obtained by adding and mixing an appropriate amount of the powder of the above-mentioned cellulose acylate, dispersing and kneading the resulting mixed raw material powder in an organic vehicle, applying a ceramic paste for forming the ceramic insulating layer, and drying the applied ceramic paste.

[0031] The insulating layer 30 may contain glass. The insulating layer 30 may be a sintered body of glass ceramics. The type of glass is not particularly limited, but examples include borosilicate glass and crystallized glass. The insulating layer 30 may contain the same glass as the glass contained in the element body 10.

[0032] The insulating layer 30 may have the same main component as the element body 10. The insulating layer 30 may also have the same composition as the element body 10.

[0033] The first electrode 21 and the second electrode 22 will be described below.

[0034] The content of the non-conductive component in the first electrode 21 is 3% by weight or more and 40% by weight or less. The content of the non-conductive component in the second electrode 22 is 0% by weight or more and 10% by weight or less. The content of the non-conductive component in the first electrode 21 is the same as or higher than the content of the non-conductive component in the second electrode 22.

[0035] In the present invention, the content of non-conductive components refers to the content of components constituting an electrode, excluding the conductive components Cu and Ag. The content of non-conductive components in an electrode can be calculated by observing the cross section of the electrode using scanning electron microscope-energy dispersive X-ray spectroscopy (SEM-EDX). Specifically, the content of conductive components is calculated using the following method. First, the weight ratio of each element in the cross section of the electrode is measured by elemental analysis using SEM-EDX. The sum of the weight ratios of each element detected by SEM-EDX, excluding C and O, is taken as 100 wt% as the total weight. The sum of the weight ratios of Cu and Ag relative to the total weight is the content of conductive components. Furthermore, the content of non-conductive components is the remaining percentage obtained by subtracting the weight ratios of Cu and Ag from the total weight.

[0036] The effects of the content of the non-conductive component in the first electrode 21 and the second electrode 22 being within the above range will be described below.

[0037] FIG. 3 is a cross-sectional view showing a typical way in which cracks occur in the ceramic substrate of the present invention.

[0038] FIG. 3 shows that a crack has occurred between the second electrode 22 and the insulating layer 30. When the content of non-conductive components in the second electrode 22 is 0 wt % or more and 10 wt % or less, the adhesion between the second electrode 22 and the insulating layer 30 is weak. Here, when stress that tends to peel the electrodes is applied to the ceramic substrate 1, the second electrode 22 and the insulating layer 30 are likely to peel off, and cracks are likely to occur along the boundary between the second electrode 22 and the insulating layer 30. At the inner end 31 of the insulating layer 30, where the crack propagates, the first electrode 21 and the second electrode 22 are in close contact and have high resistance to stress, so the crack stops propagating at the inner end 31 of the insulating layer 30. Therefore, the occurrence of cracks that would fracture the internal conductor 40 provided inside the element body 10 is suppressed, and electrical continuity from the terminal electrode 20 to the internal conductor 40 can be ensured. Furthermore, cracks occurring along the boundary between the second electrode 22 and the insulating layer 30 relieve stress on the terminal electrode 20 and the insulating layer 30, improving the thermal stress resistance of the terminal electrode 20 and the insulating layer 30.

[0039] If the content of non-conductive components in the first electrode 21 is 3 wt % or more, the adhesion between the first electrode 21 and the element body 10 can be strengthened. This prevents cracks from developing between the first electrode 21 and the element body 10. This prevents the first electrode 21 from peeling off from the element body 10, ensuring electrical continuity from the terminal electrode 20 to the internal conductor 40.

[0040] If the content of the non-conductive component in the first electrode 21 is 40 wt % or less, the strength of the first electrode 21 itself can be increased. Therefore, cracks that have reached the inner end 31 of the insulating layer 30 are prevented from progressing through the inside of the first electrode 21, and electrical continuity from the terminal electrode 20 to the internal conductor 40 can be ensured.

[0041] If the content of non-conductive components in the first electrode 21 is the same as or higher than the content of non-conductive components in the second electrode 22, cracks are likely to occur along the boundary between the second electrode 22 and the insulating layer 30. At the inner end 31 of the insulating layer 30, where the crack propagates, the first electrode 21 and the second electrode 22 are in close contact and have high resistance to stress, so the crack stops propagating at the inner end 31 of the insulating layer 30. Therefore, the occurrence of cracks that would break the internal conductor 40 provided inside the element body 10 is suppressed, and electrical continuity from the terminal electrode 20 to the internal conductor 40 can be ensured.

[0042] FIG. 4 is a cross-sectional view that schematically shows how cracks occur in a ceramic substrate of a comparative example in which the second electrode and the insulating layer have strong adhesion.

[0043] FIG. 4 shows the occurrence of a crack that passes through the insulating layer 30 and the element body 10 and fractures the internal conductor 40. The ceramic substrate 301 shown in FIG. 4 has a non-conductive component content in the second electrode 22 that is higher than 10% by weight. Therefore, the adhesion between the second electrode 22 and the insulating layer 30 is stronger than that of the ceramic substrate 1 shown in FIG. 3. When stress that tends to peel the electrodes is applied to the ceramic substrate 301, the stress concentrates at the outer edge 22e of the second electrode 22, easily generating a crack that originates at the outer edge 22e of the second electrode 22 and penetrates the insulating layer 30. In this case, the direction of crack propagation cannot be controlled, and there is no part that suppresses the crack propagation before it reaches the element body 10. Therefore, there is a risk that the crack will propagate into the element body 10. Therefore, if the internal conductor 40 provided inside the element body 10 is fractured, electrical continuity from the terminal electrode 20 to the internal conductor 40 may be interrupted. In FIG. 4, a crack originating from the outer edge 22 e of the second electrode 22 passes through the outer edge 21 e of the first electrode 21 , reaches the inside of the element body 10 , and breaks the internal conductor 40 .

[0044] Furthermore, when the content of non-conductive components in the second electrode 22 is higher than the content of non-conductive components in the first electrode 21, cracks that pass through the interior of the insulating layer 30 as shown in Fig. 4 are likely to occur, rather than cracks that run along the boundary between the second electrode 22 and the insulating layer 30 as shown in Fig. 3. As a result, there is a risk that the cracks will progress into the element body 10, causing the internal conductor 40 to break, thereby interrupting electrical continuity from the terminal electrode 20 to the internal conductor 40.

[0045] FIG. 5 is a cross-sectional view that schematically shows how cracks occur in a ceramic substrate of a comparative example in which the adhesion between the first electrode and the element body is weak.

[0046] Figure 5 shows that a crack has occurred that passes through the inside of the first electrode 21 and between the first electrode 21 and the element body 10. In the ceramic substrate 302 shown in Figure 5, the content of non-conductive components in the first electrode 21 is less than 3 wt%. Therefore, the adhesion between the first electrode 21 and the element body 10 is weaker than in the ceramic substrate 1 shown in Figure 3. When stress that tends to peel the electrode is applied to the ceramic substrate 302, a crack is likely to occur that passes through the inside of the first electrode 21 and between the first electrode 21 and the element body 10. If the first electrode 21 peels off from the element body 10 and the via conductor 41, electrical continuity between the terminal electrode 20 and the internal conductor 40 may be interrupted.

[0047] FIG. 6 is a cross-sectional view that schematically shows how cracks occur in a ceramic substrate of a comparative example in which the strength of the first electrode itself is low.

[0048] Figure 6 shows that a crack has occurred that passes through the inside of the first electrode 21 and the inside of the element body 10 and fractures the internal conductor 40. In the ceramic substrate 303 shown in Figure 6, the content of non-conductive components in the first electrode 21 is higher than 40 wt%. Therefore, the strength of the first electrode 21 itself is lower than that of the ceramic substrate 1 shown in Figure 3. When stress that tends to peel the electrode is applied to the ceramic substrate 303, a crack that reaches the inner end 31 of the insulating layer 30 is likely to propagate through the inside of the first electrode 21. If the crack then propagates into the element body 10 and fractures the internal conductor 40, there is a risk of electrical continuity from the terminal electrode 20 to the internal conductor 40 being interrupted.

[0049] Increasing the content of non-conductive components in the first electrode 21 can strengthen the adhesion between the first electrode 21 and the element body 10. On the other hand, decreasing the content of non-conductive components in the first electrode 21 can increase the strength of the first electrode 21 itself. From the above viewpoints, the content of non-conductive components in the first electrode 21 is preferably 5% by weight or more and 20% by weight or less. The content of non-conductive components in the first electrode 21 is more preferably 10% by weight or more and 20% by weight or less. The content of non-conductive components in the first electrode 21 may be 10% by weight or more and 15% by weight or less.

[0050] If the content of the non-conductive component in the second electrode 22 is low, cracks are more likely to occur along the boundary between the second electrode 22 and the insulating layer 30. From the above viewpoint, the content of the non-conductive component in the second electrode 22 is preferably 0.5 wt % or more and 6 wt % or less. The content of the non-conductive component in the second electrode 22 is more preferably 0.5 wt % or more and 3 wt % or less.

[0051] The content of the non-conductive component in the first electrode 21 is preferably higher than the content of the non-conductive component in the second electrode 22. In this case, cracks are more likely to occur along the boundary between the second electrode 22 and the insulating layer 30, so that electrical continuity from the terminal electrode 20 to the internal conductor 40 can be more sufficiently ensured.

[0052] The conductive components and non-conductive components contained in the first electrode 21 and the second electrode 22 will be described in detail below.

[0053] The first electrode 21 and the second electrode 22 contain Cu or Ag as a conductive component. The first electrode 21 and the second electrode 22 may contain only one of Cu and Ag as a conductive component, or may contain both Cu and Ag.

[0054] The first electrode 21 and the second electrode 22 may contain at least one of glass and a filler as a non-conductive component.

[0055] When the first electrode 21 or the second electrode 22 contains glass and a filler as non-conductive components, the content of the non-conductive components means the sum of the content of the glass and the content of the filler.

[0056] The glass used as the non-conductive component is not particularly limited, and examples thereof include borosilicate glass and crystallized glass. The glass used as the non-conductive component may be the same glass as that contained in the element body 10, or may be the same glass as that contained in the insulating layer 30. The glass used as the non-conductive component is preferably the same glass as that contained in the element body 10 and the insulating layer 30. The glass used in the first electrode 21 or the second electrode 22 strengthens the adhesion between the first electrode 21 or the second electrode 22 and the insulating layer 30.

[0057] An example of glass as a non-conductive component is a glass containing 44.0 to 69.0% by weight of RO (R is at least one alkaline earth metal selected from Ba, Ca, and Sr), SiO ２ 14.2 to 30.0% by weight of B ２ O ３ 10.0 to 20.0 wt % of Al ２ O ３ 0.5 to 4.0% by weight, Li ２ % of O and 0.1 to 5.5 wt % of MgO. Another example of glass as a non-conductive component is SiO ２ The content of B is 15% by weight or more and 65% by weight or less, ２ O ３ The content of B is 11% by weight or more and 30% by weight or less, ２ O ３ SiO ２ Weight ratio (SiO ２ / B ２ O ３ ) is 1.21 or more, and Al to ZnO ２ O ３ Weight ratio (Al ２ O ３ / ZnO) is 0.75 or more and 1.64 or less.

[0058] The filler as a non-conductive component is not particularly limited, but may be a ceramic, for example, Al ２ O ３ , ZrO ２ , Mg ２ SiO ４ , SiO ２ The filler as a non-conductive component is preferably a ceramic having the same composition as the ceramic contained in the element body 10 and the insulating layer 30. The filler contained in the first electrode 21 or the second electrode 22 strengthens the adhesion between the first electrode 21 or the second electrode 22 and the insulating layer 30.

[0059] In one aspect of the present invention, the content of the non-conductive component in the first electrode 21 and the second electrode 22 may be the sum of the content of the glass and the filler. In this case, the content of the non-conductive component in the first electrode 21 and the second electrode 22 may be measured by measuring the content of the glass and the filler in the first electrode 21 and the second electrode 22.

[0060] In one aspect of the present invention, the content of the non-conductive component in the first electrode 21 and the second electrode 22 may be the content of glass. In this case, the content of the non-conductive component in the first electrode 21 and the second electrode 22 may be measured by measuring the content of glass in the first electrode 21 and the second electrode 22.

[0061] The glass content in the first electrode 21 may be 0 wt % or more and 40 wt % or less, 3 wt % or more and 40 wt % or less, 5 wt % or more and 20 wt % or less, 10 wt % or more and 20 wt % or less, or 10 wt % or more and 15 wt % or less. The first electrode 21 may contain only glass as a non-conductive component.

[0062] The content of the filler in the first electrode 21 may be 0% by weight or more and 40% by weight or less, 3% by weight or more and 40% by weight or less, 5% by weight or more and 20% by weight or less, 10% by weight or more and 20% by weight or less, or 10% by weight or more and 15% by weight or less. The first electrode 21 may contain only the filler as a non-conductive component.

[0063] The total content of the glass and the filler in the first electrode 21 may be 0 wt % or more and 40 wt % or less, 3 wt % or more and 40 wt % or less, 5 wt % or more and 20 wt % or less, 10 wt % or more and 20 wt % or less, or 10 wt % or more and 15 wt % or less. The first electrode 21 may contain only glass and filler as non-conductive components.

[0064] The glass content in the second electrode 22 may be 0 wt % or more and 10 wt % or less, 0.5 wt % or more and 6 wt % or less, or 0.5 wt % or more and 3 wt % or less. The second electrode 22 may contain only glass as a non-conductive component.

[0065] The content of the filler in the second electrode 22 may be 0% by weight or more and 10% by weight or less, 0.5% by weight or more and 6% by weight or less, or 0.5% by weight or more and 3% by weight or less. The second electrode 22 may contain only the filler as a non-conductive component.

[0066] The total content of the glass and the filler in the second electrode 22 may be 0 wt % or more and 10 wt % or less, 0.5 wt % or more and 6 wt % or less, or 0.5 wt % or more and 3 wt % or less. The second electrode 22 may contain only glass and filler as non-conductive components.

[0067] The glass content in the first electrode 21 is preferably the same as or higher than the glass content in the second electrode 22. The glass content in the first electrode 21 is more preferably higher than the glass content in the second electrode 22.

[0068] The filler content in the first electrode 21 is preferably the same as or higher than the filler content in the second electrode 22. The filler content in the first electrode 21 is more preferably higher than the filler content in the second electrode 22.

[0069] The sum of the glass content and the filler content in the first electrode 21 is preferably the same as or higher than the sum of the glass content and the filler content in the second electrode 22. The sum of the glass content and the filler content in the first electrode 21 is more preferably higher than the sum of the glass content and the filler content in the second electrode 22.

[0070] When measuring the glass content and filler content in the first electrode 21 and the second electrode 22, the glass and the filler can be distinguished or separated by a method of analyzing the electron diffraction pattern using a scanning electron microscope (SEM) or a transmission electron microscope (TEM), or by a method of dissolving the glass portion with hydrogen fluoride or the like.

[0071] As described above, the content of the non-conductive component can be calculated by measuring the weight ratio of each element in the cross section of the electrode using SEM-EDX. This calculation method estimates the weight ratio of the non-conductive component added when the raw materials for the electrode were prepared from the weight ratio of each element in the electrode after firing. Therefore, the content of the non-conductive component in the first electrode 21 and the second electrode 22 may be calculated from the weight ratio of each element when the raw materials were prepared.

[0072] When the proportions of the components used to form the first electrode and the second electrode are known at the time of preparing the raw materials, the proportion of the total weight of the glass and the filler relative to the total weight of Cu, Ag, glass, and filler added at the time of preparing the raw materials may be calculated as the content of the non-conductive component.When glass is used as the only non-conductive component in the first electrode 21 or the second electrode 22, the proportion of the weight of the glass relative to the total weight of Cu, Ag, and glass added at the time of preparing the raw materials may be calculated as the content of the non-conductive component.

[0073] The relationship between the first electrode 21 and the second electrode 22 will be described below with reference to FIGS.

[0074] In a cross-sectional view of a portion where the first electrode 21, the insulating layer 30, and the second electrode 22 are stacked in this order from the outer surface side of the element body 10 in the thickness direction, the thickness of the first electrode 21 (the length indicated by the double-headed arrow t1 in FIG. 1 ) at the inner end 31 of the insulating layer 30 is preferably the same as or thicker than the thickness of the second electrode 22 (the length indicated by the double-headed arrow t2 in FIG. 1 ). In this case, the thick first electrode 21 further increases the resistance to stress at the inner end 31 of the insulating layer 30, thereby more sufficiently ensuring electrical continuity from the terminal electrode 20 to the internal conductor 40.

[0075] 1, the thickness of the first electrode 21 (length indicated by double-headed arrow t1 in FIG. 1) at the inner end 31 of the insulating layer 30 is thicker than the thickness of the second electrode 22 (length indicated by double-headed arrow t2 in FIG. 1). The thickness of the first electrode 21 (length indicated by double-headed arrow t1 in FIG. 1) may be the same as the thickness of the second electrode 22 (length indicated by double-headed arrow t2 in FIG. 1).

[0076] The thickness of the first electrode 21 at the inner end 31 of the insulating layer 30 (the length indicated by the double-headed arrow t1 in FIG. 1 ) may be, for example, 5 μm or more and 20 μm or less. The thickness of the second electrode 22 at the inner end 31 of the insulating layer 30 (the length indicated by the double-headed arrow t2 in FIG. 1 ) may be, for example, 5 μm or more and 15 μm or less. The ratio (t1 / t2) of the thickness of the first electrode 21 to the thickness of the second electrode 22 at the inner end 31 of the insulating layer 30 is not particularly limited, and may be, for example, 1.0 or more and 4.0 or less, 1.0 or more and 2.0 or less, or more than 1.0 and 2 or less.

[0077] In a plan view seen from the thickness direction perpendicular to the outer surface of the element body 10, the outer edge 21 e of the first electrode 21 preferably overlaps the outer edge 22 e of the second electrode 22 or is located further outward than the outer edge 22 e of the second electrode 22. In other words, in a plan view seen from the thickness direction perpendicular to the outer surface of the element body 10, the entire second electrode 22 preferably overlaps the first electrode 21. In this case, by suppressing stress concentration at the outer edge 22 e of the second electrode 22, it is possible to further suppress the occurrence of cracks that pass through the interior of the insulating layer 30 and the interior of the element body 10 and fracture the internal conductor 40, as shown in FIG. 4 . This makes it possible to more sufficiently ensure electrical continuity from the terminal electrode 20 to the internal conductor 40.

[0078] In a plan view seen from the thickness direction perpendicular to the outer surface of the element body 10, the area of ​​the first electrode 21 is preferably the same as or larger than the area of ​​the second electrode 22. In this case, by suppressing stress concentration at the outer edge portion 22e of the second electrode 22, it is possible to further suppress the occurrence of cracks that pass through the interior of the insulating layer 30 and the interior of the element body 10 and fracture the internal conductor 40, as shown in Fig. 4. This makes it possible to more sufficiently ensure electrical continuity from the terminal electrode 20 to the internal conductor 40.

[0079] 1 and 2 , in a plan view of the ceramic substrate 1 seen from the thickness direction perpendicular to the outer surface of the element body 10, the outer edge 21 e of the first electrode 21 overlaps the outer edge 22 e of the second electrode 22. In addition, in a plan view of the thickness direction perpendicular to the outer surface of the element body 10, the area of ​​the first electrode 21 is the same as the area of ​​the second electrode 22.

[0080] In the thickness direction perpendicular to the outer surface of the element body 10, the width of the overlapping portion (length indicated by the double-headed arrow w1 in FIG. 1 ) of the first electrode 21, the insulating layer 30, and the second electrode 22 in this order from the outer surface side of the element body 10 is not particularly limited, but may be, for example, 10 μm or more and 75 μm or less. When the width of the overlapping portion of the first electrode 21, the insulating layer 30, and the second electrode 22 in this order is 10 μm or more, the insulating layer 30 can sufficiently improve the adhesion between the terminal electrode 20 and the element body 10. On the other hand, when the width of the overlapping portion of the first electrode 21, the insulating layer 30, and the second electrode 22 in this order is small, the distance between the edge of the substrate and the electrode and the distance between the electrodes can be increased. In addition, the bonding area between the first electrode 21 and the second electrode 22 is increased, thereby strengthening the bond between the first electrode 21 and the second electrode 22. For these reasons, the width of the portion where the first electrode 21, the insulating layer 30, and the second electrode 22 overlap in this order may be, for example, 75 μm or less. The width of the portion where the first electrode 21, the insulating layer 30, and the second electrode 22 overlap in this order may be 20 μm or more and 40 μm or less. In a plan view seen from the thickness direction orthogonal to the outer surface of the element body 10, the width of the portion where the first electrode 21, the insulating layer 30, and the second electrode 22 overlap in this order may be constant. Furthermore, in a plan view seen from the thickness direction orthogonal to the outer surface of the element body 10, the width of the portion where the first electrode 21, the insulating layer 30, and the second electrode 22 overlap in this order may be different on each side of the electrode.

[0081] 1 , the width of the portion where the insulating layer 30 covers the first electrode 21 is the same as the width of the portion where the first electrode 21, the insulating layer 30, and the second electrode 22 overlap in this order. The width of the portion where the insulating layer 30 covers the first electrode 21 may be larger than the width of the portion where the first electrode 21, the insulating layer 30, and the second electrode 22 overlap in this order. The width of the portion where the insulating layer 30 covers the first electrode 21 may be 10 μm or more and 75 μm or less, or may be 20 μm or more and 40 μm or less.

[0082] 1 , the first electrode 21 is located inside (below in FIG. 1 ) a plane including the outer surface 11 of the portion of the outer surface of the element body 10 where the terminal electrode 20 and the insulating layer 30 are not provided. The first electrode 21 may be located so as to pass through a plane including the outer surface 11 of the portion of the outer surface of the element body 10 where the terminal electrode 20 and the insulating layer 30 are not provided. The first electrode 21 may also be located outside (upper in FIG. 1 ) a plane including the outer surface 11 of the portion of the outer surface of the element body 10 where the terminal electrode 20 and the insulating layer 30 are not provided.

[0083] 1, the outer surface of the second electrode 22 and the outer surface of the insulating layer 30 are located outside (upper side in FIG. 1) the outer surface of the element body 10, but the outer surface 11 of the portion of the outer surface of the element body 10 where the terminal electrode 20 and the insulating layer 30 are not provided may be flush with the outer surface of the second electrode 22 and the outer surface of the insulating layer 30. Furthermore, the second electrode 22 and the insulating layer 30 may be located inside (lower side in FIG. 1) a plane including the outer surface 11 of the portion of the outer surface of the element body 10 where the terminal electrode 20 and the insulating layer 30 are not provided.

[0084] Next, an example of a method for manufacturing the ceramic substrate of the present invention will be described with reference to an example of manufacturing an electronic component (LC filter) in which an inductance element and a capacitance element are formed by internal conductors provided inside the ceramic substrate body.

[0085] Fig. 7 is a cross-sectional view schematically showing the process of forming a first conductive paste layer that will become a first electrode after firing. Fig. 8 is a plan view schematically showing the process of forming a first conductive paste layer that will become a first electrode after firing. Note that, to simplify the explanation of the ceramic substrate, internal conductors are not shown in Figs. 7 to 17, but at least one internal conductor is provided inside the element body.

[0086] First, a plurality of ceramic green sheets 110 are prepared. The ceramic green sheets 110 become the ceramic layers of the element body 10 after firing.

[0087] The ceramic green sheet 110 is formed, for example, by forming a slurry containing ceramic powder, an organic binder, and a solvent into a sheet by a doctor blade method or the like. The slurry may contain various additives such as a dispersant and a plasticizer. The ceramic green sheet 110 can be made of the same material as that of the element body 10 in the description of the ceramic substrate.

[0088] A first conductive paste layer 121, which will become the first electrode 21 after firing, is formed on the ceramic green sheet 110 that is placed on the surface of the electronic component after lamination. The first conductive paste layer 121 is formed by patterning using a method such as screen printing or photolithography.

[0089] The area where the first conductive paste layer 121 is formed can be set appropriately depending on the distance between the electrodes, the distance between the electrode and the end of the electronic component, and the like.

[0090] 9A and 9B are cross-sectional and plan views each showing a process of forming an insulating paste layer that will become an insulating layer after firing, respectively.

[0091] An insulating paste layer 130, which will become the insulating layer 30 after firing, is formed on the outer edge of the first conductive paste layer 121. The insulating paste layer 130 is also formed continuously on the ceramic green sheet 110 on which the first conductive paste layer 121 is not formed. The insulating paste layer 130 is formed by forming a pattern using a method such as screen printing.

[0092] The width of the overlapping portion between the insulating paste layer 130 and the first conductive paste layer 121 (the length indicated by the double-headed arrow w1′ in FIG. 10 ) can be set as appropriate. If the width of the overlapping portion between the insulating paste layer 130 and the first conductive paste layer 121 is large, the insulating layer 30 can sufficiently improve adhesion between the first electrode 21 and the element body 10 after firing. If the width of the overlapping portion between the insulating paste layer 130 and the first conductive paste layer 121 is small, the bonding area between the first conductive paste layer 121 and the second conductive paste layer 122 (described later) becomes large, thereby strengthening the bond between the first electrode 21 and the second electrode 22 after firing. From these perspectives, the width of the overlapping portion between the insulating paste layer 130 and the first conductive paste layer 121 may be 10 μm or more and 75 μm or less, or 20 μm or more and 40 μm or less.

[0093] 11 and 12 are cross-sectional and plan views, respectively, illustrating a process of forming a second conductive paste layer that will become a second electrode after firing.

[0094] A second conductive paste layer 122, which will become the second electrode 22 after firing, is formed on the first conductive paste layer 121 and the insulating paste layer 130. The second conductive paste layer 122 is formed so as to cover the entire exposed portion of the first conductive paste layer 121. The second conductive paste layer 122 is also formed so as to cover a portion of the exposed portion of the insulating paste layer 130.

[0095] The area where the second conductive paste layer 122 is formed is determined appropriately based on the product specifications, etc. The area where the second conductive paste layer 122 is formed is preferably the same as the area where the first conductive paste layer 121 is formed, or smaller than the area where the first conductive paste layer 121 is formed.

[0096] Separately, holes for forming via conductors are formed in specific ceramic green sheets 110. The holes can be formed, for example, by laser processing. Furthermore, a conductive paste is applied in a desired shape to each surface of the specific ceramic green sheets 110 to form a conductive paste layer that will become an internal conductor after firing. The conductive paste layer can be formed by a method such as screen printing using a conductive paste containing, for example, Cu or Ag as a conductive component. Furthermore, the holes for forming the via conductors are filled with the conductive paste to form a conductive paste body that will become the via conductor after firing. In this manner, electrodes that will become the inductance elements and capacitance elements that constitute the LC filter can be formed.

[0097] Subsequently, a plurality of ceramic green sheets 110 are stacked to obtain an unfired laminate.

[0098] The resulting unfired laminate is then pressure-bonded, for example, at a temperature of 50°C to 80°C and a pressure of 100 MPa to 200 MPa. The pressure-bonding forces the first conductive paste layer 121, the second conductive paste layer 122, and the insulating paste layer 130 into the unfired laminate. As a result, as shown in FIG. 1 , in the fired ceramic substrate 1, the first electrode 21 may be located inside a plane including the outer surface 11 of the portion of the outer surface of the element body 10 where the terminal electrode 20 and the insulating layer 30 are not provided. Furthermore, by performing pressure-bonding until the second conductive paste layer 122 and the insulating paste layer 130 are flush with the outer surface of the unfired laminate, the fired ceramic substrate 1 may be flush with the outer surface 11 of the portion of the outer surface of the element body 10 where the terminal electrode 20 and the insulating layer 30 are not provided, the outer surface of the second electrode 22, and the outer surface of the insulating layer 30.

[0099] If necessary, the unfired laminate may be cut into individual chips using a dicer or a microcutter.

[0100] The surface of the unfired laminate may be barrel polished. In this case, the unfired laminate is enclosed in a small box called a barrel together with media balls that are harder than the material of the element body 10, and polishing is performed by rotating the barrel. Barrel polishing rounds the corners and ridges of the unfired laminate.

[0101] The unsintered laminate is then fired to obtain an electronic component equipped with the ceramic substrate of the present invention. The firing temperature is not particularly limited, but is preferably, for example, 800°C or higher and 1000°C or lower. The firing atmosphere is not particularly limited, and examples thereof include a nitrogen atmosphere. However, if the electrode material does not oxidize, an air atmosphere may be used.

[0102] In the above manufacturing method, the first conductive paste layer 121, the second conductive paste layer 122, and the insulating paste layer 130 are fired simultaneously, but firing may also be performed in a state where only the first conductive paste layer 121 and the insulating paste layer 130 have been formed (the state shown in FIGS. 9 and 10 ). In this case, the second conductive paste layer 122 may be formed so as to cover the fired first electrode 21, and then a heat treatment for baking may be performed to form the second electrode 22.

[0103] FIG. 13 is a cross-sectional view schematically showing a first modified example of the ceramic substrate.

[0104] 13 , in a plan view seen from the thickness direction perpendicular to the outer surface of the element body 10, the outer edge 21 e of the first electrode 21 is located further outward than the outer edge 22 e of the second electrode 22. In the ceramic substrate 1A, the area of ​​the first electrode 21 is larger than the area of ​​the second electrode 22 when seen from the thickness direction.

[0105] 14 and 15 are cross-sectional and plan views each showing a second modified example of the ceramic substrate.

[0106] 14 and 15 , the insulating layer 30 partially covers the outer surface of the second electrode 22. In Fig. 14 , in the thickness direction (the vertical direction in Fig. 14 ) perpendicular to the outer surface of the element body 10, there is a portion (the portion indicated by the double-headed arrow w2 in Fig. 14 ) in which the first electrode 21, the insulating layer 30, the second electrode 22, and the insulating layer 30 overlap in this order from the outer surface side of the element body 10. In the portion in which the first electrode 21, the insulating layer 30, the second electrode 22, and the insulating layer 30 overlap in this order from the outer surface side of the element body 10, a portion of the insulating layer 30 is sandwiched between the first electrode 21 and the second electrode 22, and a portion of the insulating layer 30 covers the outer surface of the second electrode 22.

[0107] 14 , the width of the portion where the insulating layer 30 covers the outer surface of the second electrode 22 (the length indicated by the double-headed arrow w2 in FIG. 14 ) is the same as the width of the portion where the first electrode 21, the insulating layer 30, and the second electrode 22 overlap in this order from the outer surface side of the element body 10. In FIG. 14 , the width of the portion where the insulating layer 30 covers the outer surface of the second electrode 22 (the length indicated by the double-headed arrow w2 in FIG. 14 ) may be larger or smaller than the width of the portion where the first electrode 21, the insulating layer 30, and the second electrode 22 overlap in this order from the outer surface side of the element body 10.

[0108] 15 , the overlapping portions of the first electrode 21, the insulating layer 30, the second electrode 22, and the insulating layer 30 in this order from the outer surface side of the element body 10 may be present on three sides of the terminal electrode 20. The overlapping portions of the first electrode 21, the insulating layer 30, the second electrode 22, and the insulating layer 30 in this order from the outer surface side of the element body 10 may be present on all sides of the terminal electrode 20.

[0109] 16 and 17 are cross-sectional and plan views each showing a third modified example of the ceramic substrate.

[0110] 16 and 17 , the insulating layer 30 partially covers the outer surface of the second electrode 22. In Fig. 16 , in the thickness direction (the vertical direction in Fig. 16 ) perpendicular to the outer surface of the element body 10, there is a portion (the portion indicated by the double-headed arrow w3 in Fig. 16 ) where the first electrode 21, the second electrode 22, and the insulating layer 30 overlap in this order from the outer surface side of the element body 10. In the portion where the first electrode 21, the second electrode 22, and the insulating layer 30 overlap in this order from the outer surface side of the element body 10, the insulating layer 30 is not sandwiched between the first electrode 21 and the second electrode 22.

[0111] As shown in FIG. 17 , the first electrode 21 , the second electrode 22 , and the insulating layer 30 may overlap in this order from the outer surface side of the element body 10 on three sides of the terminal electrode 20 .

[0112] The electronic component of the present invention will now be described.

[0113] The electronic component of the present invention includes the ceramic substrate of the present invention.

[0114] The electronic component is not particularly limited, but may be an electronic component in which an electronic component element such as an inductance element or a capacitance element is formed by an internal conductor provided inside the element body of a ceramic substrate. The electronic component may be an LC filter in which an inductance element and a capacitance element are formed by an internal conductor provided inside the element body of a ceramic substrate. Alternatively, the electronic component may be an electronic component in which chip components are mounted inside or on the surface of a ceramic substrate.

[0115] An example of the electronic component of the present invention will be described using an LC filter in which an inductance element and a capacitance element are formed by internal conductors provided inside the element body of a ceramic substrate.

[0116] Fig. 18 is a perspective view schematically showing an example of an electronic component of the present invention, Fig. 19 is a perspective view schematically showing an input / output terminal and a ground terminal in the example of the electronic component of the present invention, and Fig. 20 is an exploded perspective view schematically showing the example of the electronic component of the present invention.

[0117] The laminated LC filter 200 includes an element body 201 .

[0118] As shown in FIG. 18 , input / output terminals 202 a, 202 b, and a ground terminal 203 are formed on the lower main surface of an element body 201. As shown in FIG. 19 , the input / output terminals 202 a and 202 b include terminal electrodes 20 and insulating layers 30. While the details of the terminal electrodes 20 and insulating layers 30 are not shown in FIG. 19 , the configurations of the terminal electrodes 20 and insulating layers 30 are the same as those of the terminal electrodes 20 and insulating layers 30 in the ceramic substrate 1 shown in FIGS. 1 , 2 , and 3 . Furthermore, although the ground terminal 203 does not include the terminal electrodes 20 and insulating layers 30 in FIG. 19 , the ground terminal 203 may include the terminal electrodes 20 and insulating layers 30. If the ground terminal 203 includes the terminal electrodes 20 and insulating layers 30, the configurations of the terminal electrodes 20 and insulating layers 30 may be the same as those of the terminal electrodes 20 and insulating layers 30 in the ceramic substrate 1 shown in FIGS. 1 , 2 , and 3 .

[0119] As shown in FIG. 20, the element body 201 is made up of eight dielectric layers 201a to 201h made of ceramic or the like, stacked in order from the bottom up.

[0120] As shown in Figures 18, 19 and 20, when viewed in the stacking direction of the dielectric layers 201a to 201h, the base body 201 has a first side E211, a second side E212, a third side E213 and a fourth side E214, which are connected in order.

[0121] First, the dielectric layers 201a to 201h that make up the element body 201 will be described below.

[0122] An input / output terminal 202a, an input / output terminal 202b, and a ground terminal 203 are formed on the lower main surface of the dielectric layer 201a.

[0123] Five via conductors 205a to 205e are formed penetrating between the upper and lower main surfaces of the dielectric layer 201a.

[0124] A ground conductor pattern 204 is formed on the upper main surface of the dielectric layer 201a and is connected to the ground terminal 203 by via conductors 205a to 205e.

[0125] Seven via conductors 205f to 205l are formed penetrating between the upper and lower main surfaces of the dielectric layer 201b. In the exploded perspective view of Figure 20, the via conductors 205f to 205j are depicted as extending downwards relative to their actual lengths so that their connections can be seen (the same applies to the via conductors described below). The via conductors 205f to 205l are each connected to the ground conductor pattern 204.

[0126] Five capacitor conductor patterns 206a to 206e are formed on the upper main surface of the dielectric layer 201b. The capacitor conductor pattern 206a is connected to the input / output terminal 202a via a via conductor 207a. The capacitor conductor pattern 206e is connected to the input / output terminal 202b via a via conductor 207b. The via conductors 207a and 207b correspond to the via conductor 41 connected to the first electrode 21 in FIG. 1.

[0127] Seven via conductors 205f-205l are formed penetrating between the upper and lower main surfaces of the dielectric layer 201c. As mentioned above, the via conductors 205f-205l are also formed in the dielectric layer 201b, but via conductors with the same symbol formed in different dielectric layers are connected to each other. Eight other via conductors 205m-205t are also formed penetrating between the upper and lower main surfaces of the dielectric layer 201c. The via conductors 205m and 205n are each connected to the capacitor conductor pattern 206a. The via conductor 205o is connected to the capacitor conductor pattern 206b. The via conductors 205p and 205q are each connected to the capacitor conductor pattern 206c. The via conductor 205r is connected to the capacitor conductor pattern 206d. The via conductors 205s and 205t are each connected to the capacitor conductor pattern 206e.

[0128] Two capacitor conductor patterns 206f and 206g are formed on the upper main surface of the dielectric layer 201c. The capacitor conductor pattern 206f is connected to the via conductors 205m and 205n. The capacitor conductor pattern 206g is connected to the via conductors 205s and 205t.

[0129] Seven via conductors 205f to 205l and eight via conductors 205m to 205t are formed penetrating between the upper and lower main surfaces of the dielectric layer 201d.

[0130] Two capacitor conductor patterns 206h and 206i are formed on the upper main surface of the dielectric layer 201d. The capacitor conductor pattern 206h and the capacitor conductor pattern 206i are connected to each other.

[0131] Seven via conductors 205f to 205l and eight via conductors 205m to 205t are formed penetrating between the upper and lower main surfaces of the dielectric layer 201e.

[0132] Five line-like conductor patterns 217a to 217e are formed on the upper main surface of the dielectric layer 201e. The line-like conductor patterns 217a to 217e are arranged so as to extend in the same direction as the opposing first side E211 and third side E213, respectively. The line-like conductor patterns 217a to 217e are formed so that the opposing long sides are non-parallel to each other. As a result, each of the line-like conductor patterns 217a to 217e includes at least one side that is not parallel to any of the first side E211, second side E212, third side E213, and fourth side E214 of the element body 201.

[0133] One via conductor 205f is connected to the end of the line-shaped conductor pattern 217a on the second side E212 side, and two via conductors 205m and 205n are connected to the end of the line-shaped conductor pattern 217a on the fourth side E214 side. Two via conductors 205g and 205h are connected to the end of the line-shaped conductor pattern 217b on the second side E212 side, and one via conductor 205o is connected to the end of the line-shaped conductor pattern 217b on the fourth side E214 side. One via conductor 205i is connected to the end of the line-shaped conductor pattern 217c on the second side E212 side, and two via conductors 205p and 205q are connected to the end of the line-shaped conductor pattern 217c on the fourth side E214 side. Two via conductors 205j and 205k are connected to the end of the line-shaped conductor pattern 217d on the second side E212 side, and one via conductor 205r is connected to the end of the line-shaped conductor pattern 217d on the fourth side E214 side. One via conductor 205l is connected to the end of the line-shaped conductor pattern 217e on the second side E212 side, and two via conductors 205s and 205t are connected to the end of the line-shaped conductor pattern 217e on the fourth side E214 side.

[0134] As described above, a total of seven via conductors 205f-205l are connected to the end of the line-like conductor patterns 217a-217e on the second side E212 side by repeatedly increasing or decreasing the number of via conductors by 1, 2, 1, 2, and 1, and a total of eight via conductors 205m-205t are connected to the end of the line-like conductor patterns 217a-217e on the fourth side E214 side by repeatedly increasing or decreasing the number of via conductors by 2, 1, 2, 1, and 2. In other words, the laminated LC filter 200 makes the most efficient use of space possible by connecting as many via conductors 205f-205t as possible to the line-like conductor patterns 217a-217e, thereby reducing internal resistance.

[0135] Seven via conductors 205f to 205l and eight via conductors 205m to 205t are formed penetrating between the upper and lower main surfaces of the dielectric layer 201f.

[0136] Five line-like conductor patterns 227a to 227e are formed on the upper principal surface of the dielectric layer 201f. The line-like conductor patterns 227a to 227e have the same shapes as the line-like conductor patterns 217a to 217e formed on the upper principal surface of the dielectric layer 201e. In addition, via conductors 205f to 205t are connected to the line-like conductor patterns 227a to 227e at the same positions as the line-like conductor patterns 217a to 217e.

[0137] Seven via conductors 205f to 205l and eight via conductors 205m to 205t are formed penetrating between the upper and lower main surfaces of the dielectric layer 201g.

[0138] Five line-shaped conductor patterns 237a to 237e are formed on the upper principal surface of the dielectric layer 201g. The line-shaped conductor patterns 237a to 237e have the same shapes as the line-shaped conductor patterns 217a to 217e formed on the upper principal surface of the dielectric layer 201e. Via conductors 205f to 205t are connected to the line-shaped conductor patterns 237a to 237e at the same positions as the line-shaped conductor patterns 217a to 217e.

[0139] The dielectric layer 201h is a protective layer.

[0140] The laminated LC filter 200 having the above structure can be manufactured using materials and manufacturing methods that have been widely used in the past for laminated LC filters.

[0141] EXAMPLES Hereinafter, examples will be given that more specifically disclose the ceramic substrate and electronic component of the present invention, but the present invention is not limited to these examples.

[0142] LC filters of Samples No. 1 to 22 were fabricated based on the manufacturing method for electronic components (LC filters) described with reference to Figures 7 to 12 of this specification. In the LC filters of Samples No. 1 to 22, internal conductors were formed inside the element body, and the internal conductors formed inductance elements and capacitance elements. For each sample, materials for the first conductive paste layer and the second conductive paste layer were used such that the content of non-conductive components in the first electrode and the second electrode was the value shown in Table 2. The non-conductive components were RO (R is at least one alkaline earth metal selected from Ba, Ca, and Sr)-SiO ２ -B ２ O ３ -Al ２ O ３ -Li ２ O--MgO glass was used.

[0143] The LC filter of Sample No. 19 was manufactured without forming a second conductive paste layer during the manufacturing process. The LC filter of Sample No. 19 does not include a second electrode. The LC filter of Sample No. 20 was manufactured without forming a second conductive paste layer or an insulating paste layer during the manufacturing process. The LC filter of Sample No. 20 does not include a second electrode or an insulating layer. LC filters of Samples No. 1 to 22 were manufactured under the same conditions except for the above. Samples No. 1, No. 2, No. 5, No. 9, No. 13, No. 14, and Nos. 17 to 21 marked with an * in Table 2 are electronic components (LC filters) of comparative examples, not electronic components (LC filters) including the ceramic substrate of the present invention.

[0144] [Measurement of Non-metallic Content] The cross sections of the first electrode and the second electrode were observed by SEM-EDX. The sum of the weight ratios of the elements detected by SEM-EDX, excluding C and O, was taken as 100 wt% as the total weight. The weight ratios of Cu and Ag were subtracted from the total weight, and the remaining percentage was calculated as the content of non-conductive components.

[0145] [Plating Adhesion] When plating was formed on the upper surface of the second electrode, if 90% or more of the area of ​​the second electrode could be plated, it was marked as ○, and if plating adhesion was poor and less than 90%, it was marked as ×.

[0146] [Electrical Conductivity] Each sample after plating formation that had a plating adhesion rating of ◯ was mounted on a printed wiring board, which allowed for product continuity checks, by soldering at approximately 240°C for reflow. Flux cleaning was then performed. Each sample was subjected to a thermal shock test at temperatures ranging from -55°C to 125°C while monitoring the electrical continuity between the terminal electrode and the internal conductor, and the number of cycles at which electrical continuity was broken (number of cycles to break) was measured. The increase or decrease in the number of cycles to break compared to Sample No. 19 was evaluated according to the following criteria: ⊚: Electrical continuity was maintained even at 150% of the number of cycles. ◯: Electrical continuity was broken at 120% or more but less than 150% of the number of cycles. ×: Electrical continuity was broken at less than 120% of the number of cycles.

[0147] [Fracture mode] For each sample in which electrical continuity was interrupted in a thermal shock test at temperatures ranging from -55°C to 125°C, the cross section was polished and the progression of the crack was confirmed to identify the location where electrical continuity was interrupted. The manner in which cracks progressed in each fracture mode in the table is as follows. Element body crack: As shown in Figure 4, a crack occurred that passed through the inside of the insulating layer and the inside of the element body, breaking the internal conductor. Electrode peeling: As shown in Figure 5, a crack occurred that passed through the inside of the first electrode and between the first electrode and the element body. Intra-electrode fracture: As shown in Figure 6, a crack occurred that passed through the inside of the first electrode and the inside of the element body, breaking the internal conductor.

[0148]

[0149] As shown in Table 2, in the electronic component (LC filter) of the present invention, electrical continuity was marked with ◯ or ◎, confirming that electrical continuity from the terminal electrodes to the internal conductors was ensured.

[0150] The present specification discloses the following:

[0151] <1> A ceramic substrate comprising: an element body including a ceramic layer; at least one internal conductor provided inside the element body; a terminal electrode provided on an outer surface of the element body; and an insulating layer provided on the outer surface of the element body, wherein the internal conductor and the terminal electrode are electrically connected, the terminal electrode having a first electrode in contact with the outer surface of the element body and a second electrode covering the surface of the first electrode, the insulating layer covering at least a part of the outer edge of the first electrode and a part of the outer surface of the element body, and in a thickness direction perpendicular to the outer surface of the element body, there is a part where the first electrode, the insulating layer and the second electrode are overlapped in this order from the outer surface side of the element body, the first electrode has a content of non-conductive components of 3% by weight or more and 40% by weight or less, and the second electrode has a content of non-conductive components of 0% by weight or more and 10% by weight or less, A ceramic substrate, wherein the content of the non-conductive component in the first electrode is the same as or higher than the content of the non-conductive component in the second electrode.

[0152] <2> The ceramic substrate according to <1>, wherein the content of the non-conductive component in the first electrode is 10% by weight or more and 20% by weight or less.

[0153] <3> The ceramic substrate according to <1> or <2>, wherein the content of the non-conductive component in the second electrode is 0% by weight or more and 6% by weight or less.

[0154] <4> The ceramic substrate according to any one of <1> to <3>, wherein, in a cross-sectional view of a portion where the first electrode, the insulating layer, and the second electrode are stacked in this order from the outer surface side of the element body in the thickness direction, the thickness of the first electrode at an inner end of the insulating layer is the same as or thicker than the thickness of the second electrode.

[0155] <5> The ceramic substrate according to any one of <1> to <4>, wherein, in a plan view seen from the thickness direction, an area of ​​the first electrode is equal to or larger than an area of ​​the second electrode.

[0156] <6> The ceramic substrate according to any one of <1> to <5>, wherein the internal conductor includes a via conductor connected to the first electrode.

[0157] <7> An electronic component comprising the ceramic substrate according to any one of <1> to <6>.

[0158] 1, 1A, 1B, 1C, 301, 302, 303 Ceramic substrate 10, 201 Element body 11 Outer surface of a portion of the outer surface of the element body where terminal electrodes and insulating layers are not provided 20 Terminal electrode 20e Outer edge portion of terminal electrode 21 First electrode 21e Outer edge portion of first electrode 22 Second electrode 22e Outer edge portion of second electrode 30 Insulating layer 31 Inner end portion of insulating layer 40 Internal conductor 41, 42, 205a to 205t, 207a, 207b Via conductor 110 Ceramic green sheet 121 First conductive paste layer 122 Second conductive paste layer 130 Insulating paste layer 200 Multilayer LC filter 201a to 201h Dielectric layer E211 First side E212 Second side E213 Third side E214 Fourth side 202a, 202b Input / output terminals 203 Ground terminal 204 Ground conductor pattern 206a to 206i Capacitor conductor patterns 217a to 217e, 227a to 227e, 237a to 237e Line-like conductor patterns

Claims

1. an element body including a ceramic layer; At least one internal conductor provided inside the element body; a terminal electrode provided on an outer surface of the element body; an insulating layer provided on the outer surface of the element body, the internal conductor and the terminal electrode are electrically connected to each other, the terminal electrode has a first electrode in contact with the outer surface of the element body and a second electrode covering the surface of the first electrode; the insulating layer covers at least a part of an outer edge of the first electrode and a part of an outer surface of the element body; a portion in which the first electrode, the insulating layer, and the second electrode are overlapped in this order from the outer surface side of the element body in a thickness direction perpendicular to the outer surface of the element body, the content of the non-conductive component in the first electrode is 10% by weight or more and 20% by weight or less, the content of the non-conductive component in the second electrode is 0% by weight or more and 10% by weight or less, A ceramic substrate, wherein the content of the non-conductive component in the first electrode is the same as or higher than the content of the non-conductive component in the second electrode.

2. The ceramic substrate according to claim 1 , wherein the content of the non-conductive component in the second electrode is 0.5% by weight or more and 6% by weight or less.

3. In a cross-sectional view of a portion where the first electrode, the insulating layer, and the second electrode are stacked in this order from the outer surface side of the element body in the thickness direction, The ceramic substrate according to claim 1 , wherein the thickness of the first electrode at the inner end of the insulating layer is equal to or greater than the thickness of the second electrode.

4. In a plan view seen from the thickness direction, The ceramic substrate according to claim 1 , wherein the area of ​​the first electrode is equal to or larger than the area of ​​the second electrode.

5. The ceramic substrate according to claim 1 , wherein the internal conductor includes a via conductor connected to the first electrode.

6. An electronic component comprising the ceramic substrate according to claim 1 or 2.