Circuit module

Abstract

A circuit module 1 comprises: a substrate 10 having a first main surface 10a and a second main surface 10b; a resin layer 20 provided on the first main surface 10a of the substrate 10; a plurality of post electrodes 40 penetrating the resin layer 20 in the thickness direction; and mounting lands 50 covering a surface 40a of each of the post electrodes 40. Surfaces 40a of two or more neighboring post electrodes 40 among the plurality of post electrodes 40 are connected by a connection mounting land 60 that is one of the mounting lands. The connection mounting land 60 has electrode covering sections 61 that respectively cover of the surfaces 40a of the two or more neighboring post electrodes 40, and a connection section 62 that connects the electrode covering sections 61 to each other. Of the surface 20a of the resin layer 20, a portion in contact with the connection section 62 is an uneven surface 22a. Some of a metal constituting the connection section 62 enters recessed parts 27, 28 of the uneven surface 22a of the resin layer 20.

Description

Circuit module

[0001] This invention relates to a circuit module.

[0002] One known method for mounting a module with electronic components mounted on both sides onto another substrate is to provide a resin layer and a number of post electrodes penetrating the resin layer on one main surface of the module. However, such modules have a problem in that stress can concentrate at specific locations of the post electrodes, making them prone to disconnection.

[0003] For example, Patent Document 1 discloses a method to prevent fracture due to stress concentration by changing the shape of post electrodes, which are placed at corners where stress tends to concentrate, to an L-shape or an I-shape.

[0004] International Publication No. 2023 / 158970

[0005] However, in the circuit module described in Patent Document 1, the shape of the post electrode itself is L-shaped or I-shaped. In other words, the shape of the post electrode is determined at the substrate manufacturing stage, and it is not easy to change the shape midway through. As a result, there is a lack of design flexibility, and design changes are costly and time-consuming.

[0006] The present invention was made to solve the above problems and aims to provide a circuit module that offers a high degree of design flexibility and can reduce the cost and time required for design changes to suppress wire breakage.

[0007] The circuit module of the present invention comprises a substrate having a first main surface and a second main surface, a resin layer provided on the first main surface of the substrate, a plurality of post electrodes penetrating the resin layer in the thickness direction, and mounting lands covering the surfaces of the post electrodes. The surfaces of two or more adjacent post electrodes among the plurality of post electrodes are connected by a single mounting land, which is a connecting mounting land. The connecting mounting land has an electrode covering portion that covers the surfaces of the two or more adjacent post electrodes, and a connecting portion that connects the electrode covering portions. The portion of the resin layer surface that is in contact with the connecting portion is an uneven surface. A portion of the metal constituting the connecting portion is embedded in the recess of the uneven surface of the resin layer.

[0008] According to the present invention, it is possible to provide a circuit module that offers a high degree of design freedom and can reduce the cost and time required for design changes to suppress wire breakage.

[0009] Figure 1 is a schematic cross-sectional view showing an example of the circuit module of the present invention. Figure 2 is a top view of the circuit module shown in Figure 1. Figure 3 is a partially enlarged view of the region of the circuit module shown in Figure 1 where the lands for linking and mounting are provided. Figure 4 is an enlarged cross-sectional view of the vicinity of the lands for linking and mounting that constitute another example of the circuit module of the present invention. Figure 5 is an enlarged cross-sectional view of the vicinity of the lands for linking and mounting that constitute yet another example of the circuit module of the present invention. Figure 6 is an enlarged cross-sectional view of the vicinity of the lands for linking and mounting that constitute yet another example of the circuit module of the present invention. Figure 7 is an enlarged cross-sectional view and a corresponding top view of the vicinity of the lands for linking and mounting that constitute yet another example of the circuit module of the present invention. Figure 8 is a schematic diagram showing an example of a roughening process. Figure 9 is a schematic diagram showing an example of a plating deposition nucleation process. Figure 10 is a schematic diagram showing an example of an electroless plating process.

[0010] The circuit module of the present invention will be described below. However, the present invention is not limited to the following configuration and can be modified and applied as appropriate without changing the gist of the invention. Furthermore, a combination of two or more desirable configurations of each embodiment of the present invention described below also constitutes the present invention.

[0011] [Circuit Module] The circuit module of the present invention comprises a substrate having a first main surface and a second main surface, a resin layer provided on the first main surface of the substrate, a plurality of post electrodes penetrating the resin layer in the thickness direction, and mounting lands covering the surfaces of the post electrodes. The surfaces of two or more adjacent post electrodes among the plurality of post electrodes are connected by a single mounting land, which is a connecting mounting land. The connecting mounting land has an electrode covering portion that covers the surfaces of the two or more adjacent post electrodes, and a connecting portion that connects the electrode covering portions. The portion of the resin layer surface that is in contact with the connecting portion is an uneven surface. A portion of the metal constituting the connecting portion is embedded in the recess of the uneven surface of the resin layer.

[0012] Figure 1 is a schematic cross-sectional view showing an example of the circuit module of the present invention. The circuit module 1 shown in Figure 1 comprises a substrate 10 having a first main surface 10a and a second main surface 10b, a resin layer 20 provided on the first main surface 10a of the substrate 10, a plurality of post electrodes 40 penetrating the resin layer 20 in the thickness direction (indicated by arrow Z in Figure 1), and mounting lands 50 covering the surface 40a of the post electrodes 40.

[0013] Electrodes 12 are provided on the first main surface 10a and the second main surface 10b of the substrate 10. An electronic component 31 is mounted on the first main surface 10a of the substrate 10 via the electrodes 12. In addition, a number of post electrodes 40 are connected to the first main surface 10a of the substrate 10 via the electrodes 12. Furthermore, the first main surface 10a of the substrate 10 is covered with a resin layer 20, and the post electrodes 40 and the electronic component 31 are exposed on the surface 20a of the resin layer 20.

[0014] Electronic components 32, 33, and 34 are mounted on the second main surface 10b of the substrate 10 via electrodes 12. Preferably, the second main surface 10b of the substrate 10 is covered with a resin layer 70. None of the electronic components 32, 33, and 34 are exposed on the surface of the resin layer 70.

[0015] Since electronic components are mounted on both the first main surface 10a and the second main surface 10b, the substrate 10 is also a double-sided substrate.

[0016] The substrate 10 may be a printed circuit board (also referred to as a p-board) or a low-temperature co-fired ceramic (LTCC) substrate. Further, the substrate 10 may be a resin multilayer substrate in which wiring is formed on a thermoplastic resin [e.g., polyether ether ketone (PEEK), polyimide (PI), liquid crystal polymer (LCP), etc.] by a copper foil. The low-temperature co-fired ceramic (LTCC) substrate is a substrate in which insulating layers made of a low-temperature co-fired ceramic (LTCC) material are laminated and which has wiring (internal wiring) inside.

[0017] The low-temperature co-fired ceramic material is a ceramic material that can be fired at a temperature of 1000°C or lower and can be co-fired with metals such as Au, Ag, and Cu having a small specific resistance. Specifically, as the low-temperature co-fired ceramic material, a glass composite low-temperature fired ceramic material obtained by mixing a borosilicate-based glass with ceramic powders such as alumina, zirconia, magnesia, and forsterite, a crystallized glass-based low-temperature fired ceramic material using a ZnO-MgO-Al ２ O ３ -SiO ２ system crystallized glass, a BaO-Al ２ O ３ -SiO ２ system ceramic powder, or an Al ２ O ３ -CaO-SiO ２ -MgO-B ２ O ３ system non-glass-based low-temperature fired ceramic material, etc. may be mentioned.

[0018] Examples of the material for the internal wiring include metals such as Cu, Ag, and Au.

[0019] The electrode 12 is formed, for example, by plating the surface of a metal material selected from among Cu and Cu alloys, etc. with a metal material selected from among Ni and Ni alloys, etc.

[0020] The resin layer 20 contains a sealing resin. The type of sealing resin constituting the resin layer 20 is not particularly limited and may be a thermoplastic resin such as PEEK (polyether ether ketone), or a thermosetting resin such as epoxy resin. The resin layer 20 may also contain a filler in addition to the sealing resin. The material constituting the resin layer 70 may be the same as or different from the material constituting the resin layer 20.

[0021] The resin layer 20 preferably includes a filler and a sealing resin that fills the gaps in the filler. The sealing resin may also contain a metal compound that generates plating deposition nuclei by laser irradiation. The sealing resin containing the metal compound is also called LDS resin (Laser Direct Structuring resin). The LDS resin may be a thermoplastic resin or a thermosetting resin.

[0022] The thickness of the resin layer 20 is preferably, for example, 50 μm or more and 200 μm or less. The thickness of the resin layer 70 may be the same as the thickness of the resin layer 20, may be greater than the thickness of the resin layer 20, or may be less than the thickness of the resin layer 20.

[0023] The shape of the post electrode 40 is not particularly limited, but for example, it may have a cylindrical or prismatic shape. When the shape of the post electrode 40 is cylindrical or substantially cylindrical, the radius of the circle is preferably 100 μm or more and 300 μm or less.

[0024] The multiple post electrodes 40 may each have a different shape, or they may have the same shape. Furthermore, the shape of the post electrodes 40 may be changed depending on the position where they are placed (distance from the side or corner of the substrate 10), but it is preferable that all post electrodes 40 have substantially the same shape regardless of their position.

[0025] As the material constituting the post electrode 40, for example, a metallic material selected from Cu and Cu alloys can be used. As the Cu alloy, for example, a Cu-10Ni alloy (with a Cu / Ni weight ratio of 90 / 10) may be used.

[0026] Furthermore, the surfaces 40a of two or more adjacent post electrodes 40 are connected by a single mounting land 50, which is a connecting mounting land 60. In other words, the single mounting land 50 covering the surfaces 40a of two or more adjacent post electrodes 40 is the connecting mounting land 60. The mounting lands 50 other than the connecting mounting land 60 are mounting lands that cover only the surface 40a of one post electrode 40.

[0027] Figure 2 is a top view of the circuit module shown in Figure 1. Note that the line I-I in Figure 2 corresponds to the cross-sectional view shown in Figure 1.

[0028] As shown in Figure 2, the multiple post electrodes 40 provided on the circuit module 1 are arranged at approximately equal intervals in the length direction (indicated by arrow X in Figure 2) and the width direction (indicated by arrow Y in Figure 2), which are perpendicular to the thickness direction Z. However, no post electrodes 40 are placed in the area where the electronic components 31 are located.

[0029] In the circuit module 1 shown in Figure 2, the electronic component 31 is positioned close to the side surface 1e of the circuit module 1, so a post electrode 40 is not provided between the side surface 1e of the circuit module 1 and the electronic component 31. However, the position in which the electronic component is provided in the circuit module of the present invention is not particularly limited. For example, in the circuit module 1 shown in Figure 2, if the position of the electronic component 31 is changed to near the center and there is enough space between the side surface 1e of the circuit module and the electronic component 31 to accommodate a post electrode 40, then a post electrode 40 may be provided between the side surface 1e of the circuit module 1 and the electronic component 31.

[0030] The surface of the post electrode 40 is covered with mounting lands 50. In the circuit module 1, the mounting lands 50 include four linked mounting lands 60.

[0031] Each land 60 for connection and mounting covers the surface of the post electrode 40 arranged at the corner of the circuit module 1. Specifically, the planar shape of each land 60 for connection and mounting is in an L shape that connects the first post electrode 41, the second post electrode 42 adjacent to the first post electrode 41 in the X direction, and the third post electrode 43 adjacent to the first post electrode 41 in the Y direction.

[0032] The post electrode 40 covered with the mounting land 50 including the land 60 for connection and mounting is preferably made of Cu or a Cu alloy. More preferably, the post electrode 40 covered with the land 60 for connection and mounting is made of Cu or a Cu alloy.

[0033] FIG. 3 is a partially enlarged view of the region where the land 60 for connection and mounting of the circuit module shown in FIG. 1 is provided. As shown in FIG. 3, the land 60 for connection and mounting has an electrode covering portion 61 that covers the surfaces 40a of two or more adjacent post electrodes 40, and a connecting portion 62 that connects the electrode covering portions 61.

[0034] The portion of the surface of the resin layer 20 that contacts the connecting portion 62 is an uneven surface 22a. The uneven surface 22a has a recess 27 formed by removing the sealing resin 26 between the fillers 25 and a recess 28 formed by the fillers 25 being detached from the sealing resin 26.

[0035] That is, when the resin layer 20 includes the fillers 25 and the sealing resin 26 that fills the gaps between the fillers 25, the uneven surface 22a may have a recess 27 formed by removing the sealing resin 26 that fills the gaps between the fillers 25, or a recess 28 formed by the fillers 25 being detached from the sealing resin 26.

[0036] A part of the metal constituting the connecting portion 62 enters the recesses 27 and 28 of the uneven surface 22a of the resin layer 20. It is sufficient that a part of the metal constituting the connecting portion 62 enters at least one of the recesses 27 and 28 of the uneven surface 22a of the resin layer 20. Thereby, the adhesion between the land 60 for connection and mounting and the resin layer 2 exists due to the anchor effect. Even when stress is concentrated on the post electrode 40, disconnection can be suppressed.

[0037] Since stress tends to concentrate on the post electrodes arranged at the corners of the circuit module, it is preferable that, as in the circuit module 1 shown in FIG. 2, the post electrodes 40 arranged at the corners are covered with the connection mounting lands 60. In other words, it is preferable that at least one of the post electrodes arranged at the corners of the circuit module is covered with the connection mounting lands together with the post electrodes adjacent to the post electrode.

[0038] The connection mounting land 60 is preferably an electroless plating film. Examples of the electroless plating film include a Ni / Au plating film, a Cu / Ni / Au plating film, a Ni / Pd / Au plating film, and the like. These electroless plating films have high bonding properties with the resin layer and are less likely to peel off.

[0039] The maximum height of the unevenness on the uneven surface 22a is preferably 20% or more and 80% or less of the maximum thickness of the connecting portion 62. The maximum height of the unevenness on the uneven surface 22a is the length in the thickness direction between the most concave portion and the most convex portion of the uneven surface 22a, and in FIG. 3, it is indicated by the double-headed arrow t １ as shown. The maximum thickness of the connecting portion 62 is the length in the thickness direction from the most concave portion of the uneven surface 22a to the surface of the connecting portion 62, and in FIG. 3, it is indicated by the double-headed arrow t ２ as shown. The maximum thickness t ２ of the connecting portion 62 is preferably 3 μm or more and 7 μm or less.

[0040] Also, as shown in FIG. 3, it is preferable that at least a part of the side surface 40b of the post electrode 4 is in contact with the connection mounting land 60.

[0041] Figure 4 is an enlarged cross-sectional view of the vicinity of a land for link mounting, which constitutes another example of the circuit module of the present invention. The post electrode 40 shown in Figure 4 has a Ni / Au plating film 45 on its side surface 40b. When the post electrode has a Ni / Au plating film on its side surface, if the post electrode is made of Cu or a Cu alloy, the coefficient of linear expansion of the Ni / Au plating film becomes approximately intermediate between the coefficient of linear expansion of the post electrode and the coefficient of linear expansion of the sealing resin, thereby suppressing delamination between the post electrode and the sealing resin.

[0042] Figure 5 is an enlarged cross-sectional view of the vicinity of a land for linking and mounting, which constitutes yet another example of the circuit module of the present invention. In the circuit module shown in Figure 5, the surface and sides of the land for linking and mounting 60 are covered with a solder precoat 90. Since the solder precoat 90 is made of solder, it can be said that the surface and sides of the land for linking and mounting 60 are covered with solder. Alternatively, the surface and sides of the land for linking and mounting may be covered with solder bumps instead of a solder precoat.

[0043] Both solder pre-coats and solder bumps are formed primarily by printing solder paste and then heating it as needed. Solder pre-coats are formed by applying a film of solder paste to the surface of a land for joint mounting and then heating it. Solder bumps are formed by applying solder paste to the surface of a land for joint mounting in the shape of a hemispherical protrusion and then heating it. Solder bumps use more solder paste than solder pre-coats.

[0044] A layer of intermetallic compound, consisting of an intermetallic compound between the metal constituting the intermetallic mounting land and the metal constituting the solder, may be provided between the land for linking and the solder.

[0045] The composition of the intermetallic compound between the metal constituting the solder and the metal constituting the land for connecting and mounting is (Cu, Ni) ６ Sn ５ It is preferable that this be the case.

[0046] The thickness of the intermetallic compound layer is preferably 2 μm or less.

[0047] Figure 6 is an enlarged cross-sectional view of the vicinity of a land for linking, which constitutes yet another example of the circuit module of the present invention. In the circuit module shown in Figure 6, the post electrode 40 has a Ni / Au plating film 45 on its side surface. The side surface of the post electrode 40 (i.e., the Ni / Au plating film 45) is in direct contact with the land for linking, which is 60. In addition, the surface and sides of the land for linking, which is 60, are covered with a solder precoat 90.

[0048] Figure 7 shows an enlarged cross-sectional view and a corresponding top view of the vicinity of a land for link mounting, which constitute yet another example of the circuit module of the present invention.

[0049] In the example shown in Figure 7, the connecting mounting land 160 has an electrode covering portion 61 that covers the surface 40a of the post electrode 40, a connecting portion 62 that connects the electrode covering portions 61 together, and an electrode peripheral portion 64 that covers the periphery of the post electrode 40. The electrode peripheral portion 64 is in contact with the peripheral portion 24 of the resin layer 20, which is the portion that covers the periphery of the post electrode 40. Preferably, the peripheral portion 24 of the resin layer 20 also has irregularities similar to the uneven surface 22a.

[0050] As shown in Figure 7, it is preferable that the entire surface of the resin layer 20 surrounding the post electrode 40 is an uneven surface 22a, and that the entire side surface 40b of the post electrode 40 is in contact with the connecting mounting land 160. In other words, in the circuit module of the present invention, it is preferable that at least one of the post electrodes covered by the connecting mounting land has its entire side surface in contact with the connecting mounting land. When the entire side surface of the post electrode is in contact with the connecting mounting land, the contact area between the connecting mounting land and the post electrode increases, thereby improving peel resistance.

[0051] In the connecting mounting land 160 shown in Figure 7, the width W of the connecting portion 62 １ The width R of the post electrode 40 is covered by the land 60 for connecting and mounting. １ Larger than that. Width W of the connecting section. １ This refers to the maximum length of the connecting portion 62 in a direction perpendicular to the direction connecting adjacent post electrodes 40.

[0052] Width W of the connecting section １The width R of the post electrode covered by the land for linked mounting is １ It is preferable that it be between 50% and 150%.

[0053] [Method for Manufacturing Circuit Modules] The circuit module of the present invention can be manufactured, for example, by covering a substrate on which electronic components and post electrodes are arranged with a resin layer, polishing the resin layer so that the surface of the post electrodes is exposed to obtain a component mounting substrate, and then performing a roughening step, a plating deposition nucleation step, and an electroless plating step.

[0054] Furthermore, when using a post electrode with a Ni / Au plating film on its side, either use a post electrode with a Ni / Au plating film on its side beforehand, or apply the Ni / Au plating treatment to the surface of the post electrode before covering it with the resin layer.

[0055] The following describes an example of the roughening process, the plating deposition nucleation process, and the electroless plating process.

[0056] (Roughening process) In the roughening process, at least a portion of the surface of the resin layer is roughened. Figure 8 is a schematic diagram showing an example of the roughening process.

[0057] As shown in Figure 8, by roughening the surface 20a of the resin layer 20 between adjacent post electrodes 40, a portion of the resin layer 20 is removed, forming an uneven surface 22a.

[0058] The roughening treatment is not particularly limited, but examples include blasting, plasma, laser, and etching.

[0059] In this case, the roughening treatment may be applied not only to the surface of the resin layer between the post electrodes, but also to the surface of the resin layer surrounding the post electrodes. By applying the roughening treatment to the surface of the resin layer surrounding the post electrodes in addition to the surface of the resin layer between the post electrodes, the resin layer covering the sides of the post electrodes is removed, exposing the entire circumference of the sides of the post electrodes. In other words, an uneven surface is formed not only on the surface of the resin layer between the post electrodes, but also on the peripheral surface of the resin layer surrounding the post electrodes.

[0060] (Plating nucleation process) In the plating nucleation process, plating nuclei are formed on the surface of the roughened resin layer. Figure 9 is a schematic diagram showing an example of the plating nucleation process.

[0061] As shown in Figure 9, plating deposition nuclei 68 are formed on the surface of the uneven surface 22a by the plating deposition nuclei formation process.

[0062] The method for depositing plating nuclei is not particularly limited, but examples include catalyst application and the formation of a seed layer by sputtering.

[0063] In Figure 9, the plating deposition nuclei 68 are formed in layers, but the shape of the plating deposition nuclei 68 is not particularly limited. For example, the plating deposition nuclei may exist in an island-like shape.

[0064] Furthermore, by irradiating the sealing resin constituting the resin layer with a laser using LDS resin, the roughening process and the plating deposition nucleation process described above can be performed in a single step.

[0065] (Electroless Plating Process) In the electroless plating process, mounting lands and connecting mounting lands are formed. Figure 10 is a schematic diagram showing an example of the electroless plating process.

[0066] Through the electroless plating process, an electroless plating film is formed on the surface 40a of the post electrode 40 and on the uneven surface 22a of the resin layer 20 in the portion where the plating deposition nuclei 68 were formed in the plating deposition nucleus formation process.

[0067] In this case, for post electrodes 40 that have not undergone roughening treatment around them, no electroless plating film is formed on the surface 20a of the surrounding resin layer 20. In other words, for post electrodes 40 that have not undergone roughening treatment around them, an electroless plating film is formed only on its surface 40a. This electroless plating film is the normal mounting land 50.

[0068] In contrast, an electroless plating film is formed on the surface of the resin layer that has undergone the roughening process and the plating deposition nucleation process, with the plating deposition nuclei 68 as nuclei. This electroless plating film is formed integrally with the electroless plating film formed on the surface 40a of the post electrode 40, and constitutes the land 60 for linked mounting.

[0069] In other words, in the land 60 for connecting and mounting, the electrode coating portion 61, which is an electroless plating film formed on the surface 40a of the post electrode 40, and the connecting portion 62, which is an electroless plating film formed on the uneven surface 22a of the resin layer 20 between the post electrodes 40, are integrated together.

[0070] In the connecting portion 62, an electroless plating film is formed using the plating deposition nuclei 68 formed on the uneven surface 22a of the resin layer 20 as nuclei, so that the uneven surface 22a of the resin layer 20 and the connecting portion 62, which is an electroless plating film, are firmly bonded together.

[0071] Furthermore, if the resin layer covering the side surface of the post electrode is removed during the roughening process, the electroless plating film will also grow from the side surface of the post electrode during the electroless plating process. As a result, the electroless plating film growing from the side surface of the post electrode and the electroless plating film growing from the uneven surface of the resin layer are integrated to form a land for connecting and mounting.

[0072] Note that the plating nuclei are omitted in Figure 10. Plating nuclei may be too small to observe. Furthermore, if the type of metal constituting the plating nuclei is the same as the type of metal constituting the electroless plating film, it may be impossible to distinguish between the electroless plating film and the plating nuclei, and thus the plating nuclei may not be visible.

[0073] The electroless plating process may include an electroless Ni plating process and an electroless Au plating process, or it may include an electroless Cu plating process, an electroless Ni plating process and an electroless Au plating process. In the former, a Ni / Au plating film is formed, and in the latter, a Cu / Ni / Au plating film is formed. Alternatively, the electroless plating process may include an electroless Ni plating process, an electroless Pd plating process and an electroless Au plating process. In this case, a Ni / Pd / Au plating film is formed.

[0074] As described above, the shape of the electroless plating film covering the surface 20a of the resin layer 20 is equal to the shape of the surface to which the roughening process and the plating deposition nucleation process are applied. Therefore, by appropriately selecting the position of the surface to which the roughening process and the plating deposition nucleation process are applied, the position of the connecting mounting lands 60 can be controlled. Since the roughening process and the plating deposition nucleation process can be performed immediately before the electroless plating process, which is a process of forming mounting lands on the surface of a normal post electrode, it is not necessary to adjust the shape of the substrate and post electrode in advance according to the shape of the circuit module and the arrangement of the connecting mounting lands. As a result, there is a high degree of design freedom, and the cost and time required for design changes can be reduced.

[0075] After this, the surface and sides of the mounting lands may be covered with a solder precoat or solder bumps as needed. When covering the surface and sides of the mounting lands with solder, it is preferable to cover the surface and sides of all mounting lands, including those for linked mounting, with solder.

[0076] In this case, by using a metal that forms an intermetallic compound with the metal that forms the land for connecting and mounting as the metal that constitutes the solder, an intermetallic compound layer consisting of the intermetallic compound between the metal that forms the land for connecting and the metal that forms the solder can be provided between the land for connecting and the solder.

[0077] 1 Circuit module 1e Side view of the circuit module 10 Substrate 10a First main surface of the substrate 10b Second main surface of the substrate 20, 70 Resin layer 20a Surface of the resin layer 22a Uneven surface 24 Peripheral area 25 Filler 26 Sealing resin 27 Recess formed by removal of sealing resin between fillers 28 Recess formed by detachment of filler particles 31, 32, 33, 34 Electronic components 40 Post electrode 40a Surface of the post electrode 40b Side view of the post electrode 41 First post electrode 42 Second post electrode 43 Third post electrode 45 Ni / Au plating film 50 Mounting land 60, 160 Connecting mounting land 61 Electrode covering part 62 Connecting part 64 Peripheral area 68 Plating deposition nucleus 90 Solder precoat

Claims

1. A circuit module comprising: a substrate having a first main surface and a second main surface; a resin layer provided on the first main surface of the substrate; a plurality of post electrodes penetrating the resin layer in the thickness direction; and mounting lands covering the surfaces of the post electrodes, wherein the surfaces of two or more adjacent post electrodes among the plurality of post electrodes are connected by a connecting mounting land which is a single mounting land; the connecting mounting land has an electrode covering portion that covers the surfaces of the two or more adjacent post electrodes and a connecting portion that connects the electrode covering portions; the portion of the resin layer surface in contact with the connecting portion is an uneven surface; and a portion of the metal constituting the connecting portion is embedded in the recess of the uneven surface of the resin layer.

2. The circuit module according to claim 1, wherein at least one of the post electrodes covered by the connecting mounting land has at least a portion of its side surface in contact with the connecting mounting land.

3. The circuit module according to claim 1 or 2, wherein at least one of the post electrodes covered by the connecting mounting land has its entire side surface in contact with the connecting mounting land.

4. The circuit module according to any one of claims 1 to 3, wherein the resin layer comprises a filler and a sealing resin that fills the gaps of the filler, and the recess is a recess formed by removing the sealing resin that fills the gaps of the filler, and / or a recess formed by the filler detaching from the sealing resin.

5. The circuit module according to any one of claims 1 to 4, wherein the maximum height of the irregularities on the uneven surface is 20% or more and 80% or less of the maximum thickness of the connecting portion.

6. The circuit module according to any one of claims 1 to 5, wherein the width of the connecting portion is 50% or more and 150% or less of the width of the post electrode covered by the connecting mounting land.

7. The circuit module according to any one of claims 1 to 6, wherein the post electrode covered by the connecting mounting land has a Ni / Au plating film on its side surface.

8. The circuit module according to any one of claims 1 to 7, wherein the land for connecting and mounting is an electroless plating film.

9. The circuit module according to any one of claims 1 to 8, wherein the post electrode covered by the connecting mounting land is made of Cu or a Cu alloy.

10. The circuit module according to any one of claims 1 to 9, wherein the surface and sides of the land for connecting and mounting are covered with solder.

11. The circuit module according to claim 10, wherein an intermetallic compound layer is provided between the connecting mounting land and the solder, the intermetallic compound layer being made of an intermetallic compound between the metal constituting the connecting mounting land and the metal constituting the solder.

12. The circuit module according to any one of claims 1 to 11, wherein at least one of the post electrodes positioned at the corners of the circuit module is covered with the connecting mounting land together with the post electrode adjacent to it.

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