Module

Abstract

This module (101) comprises: a first substrate (51) having a substrate first surface (51a); an inductor (31) having a winding axis (31x) and mounted on the substrate first surface (51a); and a sealing resin (6a) disposed so as to cover the inductor (31) and the substrate first surface (51a). The inductor (31) has an inductor first surface (31f) perpendicular to the winding axis (31x). A metal foil (15) is disposed so as to cover at least a partial region of the inductor first surface (31f), and the metal foil (15) is grounded.

Description

Module

[0001] The present invention relates to a module.

[0002] A module is known in which electronic components are mounted on a substrate, covered with a sealing resin, and a shielding film is disposed so as to cover the surface of the sealing resin. In such a module, when the electronic component is an electronic component with a shielding film, the generation of parasitic capacitance between the shielding film provided on the electronic component with a shielding film and the shielding film provided on the surface of the sealing resin of the module becomes a problem. In International Publication WO2022 / 009777A1 (Patent Document 1), as a countermeasure against such a problem, the shielding film covering the surface of the sealing resin of the module is configured to be divided into a first shielding portion and a second shielding portion by being separated by a groove. The first shielding portion is in a so-called floating state. The first shielding portion has a positional relationship overlapping at least a part of the shielding film provided on the electronic component with a shielding film. Such a configuration suppresses the generation of the above-described parasitic capacitance.

[0003] In International Publication WO2022 / 014348A1 (Patent Document 2), as a countermeasure against the same problem, a shielding region and a non-shielding region are provided on the surface of the sealing substrate on the side far from the substrate. The non-shielding region has a positional relationship overlapping at least a part of the shielding film provided on the electronic component with a shielding film. Such a configuration suppresses the generation of the above-described parasitic capacitance.

[0004] International Publication WO2022 / 009777A1 International Publication WO2022 / 014348A1

[0005] In Patent Documents 1 and 2, when the electronic component mounted on the substrate is an electronic component with a shielding film, the generation of parasitic capacitance between the shielding film provided on the electronic component with a shielding film and the shielding film provided on the surface of the sealing resin of the module is suppressed. However, in reality, even when the electronic component is not an electronic component with a shielding film, the generation of parasitic capacitance between the wiring provided on the electronic component and the shielding film provided on the surface of the sealing resin of the module may also become a problem.

[0006] When the electronic components mounted on the circuit board are inductors, it is necessary to enhance the shielding performance to block the magnetic field lines generated by the inductors. Furthermore, a reduction in the overall height and area of ​​the module is also required.

[0007] Therefore, the present invention aims to provide a module that can enhance the shielding performance for an inductor without degrading the characteristics of the mounted inductor.

[0008] To achieve the above objective, a module according to the present invention comprises a first substrate having a first substrate surface, an inductor having a winding shaft and mounted on the first substrate surface, and a sealing resin arranged to cover the inductor and the first substrate surface, wherein the inductor has an inductor first surface perpendicular to the winding shaft, a metal foil is arranged to cover at least a portion of the area of ​​the inductor first surface, and the metal foil is grounded.

[0009] According to the present invention, the shielding performance for inductors can be enhanced without degrading the characteristics of the mounted inductor.

[0010] This is a cross-sectional view of a module in Embodiment 1 according to the present invention. This is a plan view of a module in Embodiment 1 according to the present invention. This is a plan view of the metal foil and bonding material removed from the module in Embodiment 1 according to the present invention. This is a cross-sectional view of the metal foil and bonding material removed from the module in Embodiment 1 according to the present invention. This is a cross-sectional view of a module in Embodiment 2 according to the present invention. This is a plan view of a module in Embodiment 2 according to the present invention. This is a plan view of the first metal foil included in the module in Embodiment 2 according to the present invention. This is a plan view of the second metal foil included in the module in Embodiment 2 according to the present invention. This is a cross-sectional view of a module included in Embodiment 2 according to the present invention. This is a plan view of the first metal foil and the second metal foil included in the module in Embodiment 2 according to the present invention, with an insulating material in between. This is a plan view of the first metal foil included in the first modified example of the module in Embodiment 2 according to the present invention. This is a plan view of the second metal foil included in the first modified example of the module in Embodiment 2 according to the present invention. This is a plan view of the first metal foil and the second metal foil included in the first modified example of the module in Embodiment 2 according to the present invention, with an insulating material in between. This is a plan view of the first metal foil included in a second modified example of the module in Embodiment 2 of the present invention. This is a plan view of the second metal foil included in a second modified example of the module in Embodiment 2 of the present invention. This is a plan view of the first metal foil and the second metal foil superimposed on each other with an insulating material in between, included in a second modified example of the module in Embodiment 2 of the present invention. This is a cross-sectional view of the module in Embodiment 3 of the present invention. This is a cross-sectional view of the module in Embodiment 4 of the present invention. This is a view of the inductor and its vicinity in the module in Embodiment 4 of the present invention, as seen from the right side in Figure 18. This is a cross-sectional view of the module in Embodiment 5 of the present invention. This is a cross-sectional view of the module in Embodiment 6 of the present invention. This is a cross-sectional view of the module in Embodiment 7 of the present invention.

[0011] The dimensional ratios shown in the drawings do not necessarily accurately reflect reality, and may be exaggerated for illustrative purposes. In the following explanation, the concepts of "up" or "down" do not necessarily refer to absolute up or down, but rather to relative up or down within the illustrated orientation.

[0012] (Embodiment 1) A module in Embodiment 1 according to the present invention will be described with reference to Figures 1 to 4. A cross-sectional view of module 101 in this embodiment is shown in Figure 1. A plan view of module 101 is shown in Figure 2. However, for the sake of explanation, Figure 2 shows the state with the sealing resin 6a removed. Therefore, in Figure 2, the group of parts that are normally covered and hidden by the sealing resin 6a are visible.

[0013] As shown in Figure 1, the module 101 comprises a first substrate 51, an inductor 31, and a sealing resin 6a. The first substrate 51 has a first substrate surface 51a. The inductor 31 has a winding shaft 31x and is mounted on the first substrate surface 51a. The sealing resin 6a is arranged to cover the inductor 31 and the first substrate surface 51a. The inductor 31 has an inductor first surface 31f perpendicular to the winding shaft 31x. A metal foil 15 is arranged to cover at least a portion of the inductor first surface 31f. The metal foil 15 is grounded.

[0014] In the example shown here, preferably, the metal foil 15 is arranged to cover at least a portion of the inductor's first surface 31f, including the point where the extension of the winding axis 31x intersects the inductor's first surface 31f.

[0015] The inductor 31 has a built-in coil wiring 31c. The shape of the coil wiring 31c determines the direction of the winding axis 31x. In Figure 1, the shape of the coil wiring 31c is schematically shown. The detailed shape of the actual coil wiring 31c may not be exactly as shown here, but the direction of the winding axis 31x can be determined from the shape of the coil wiring 31c shown in Figure 1. In the example shown here, the winding axis 31x of the inductor 31 is parallel to the first surface 51a of the substrate. Therefore, the first surface 31f of the inductor perpendicular to the winding axis 31x is the side surface of the inductor 31. The metal foil 15 is arranged to cover the side surface of the inductor 31. The metal foil 15 is attached to the side surface of the inductor 31 via a bonding material 16. In this example, the metal foil 15 covers the entire side surface of the inductor 31, but it may also cover only a part of the side surface of the inductor 31. To more reliably shield the magnetic field lines generated from the coil wiring 31c, it is preferable that the metal foil 15 covers the entire side surface of the inductor 31.

[0016] In addition to the inductor 31, components 32, 33, 34, etc. may also be mounted on the first surface 51a of the substrate. The first surface 51a of the substrate has a first recess 12. The first recess 12 can also be understood as a locally lowered portion of the first surface 51a of the substrate. The first recess 12 is not necessarily located away from the outer periphery of the first surface 51a of the substrate; as shown in Figures 1 and 2, the first recess 12 may be located in contact with the edge of the first substrate 51. In this case, a portion of the outer periphery of the first recess 12 is adjacent to a raised portion, and the other portion forms the edge of the first substrate 51. In this embodiment, as shown in Figure 2, the first recess 12 is located at the corner of the first substrate 51. The inductor 31 is mounted on the first surface 51a of the substrate inside the first recess 12. Electrodes 23 and 24 are arranged on the bottom surface of the first recess 12. The external terminals of the inductor 31 are electrically connected to the electrodes 24. Electrode 23 is a ground electrode. The metal foil 15 is electrically connected to the electrode 23.

[0017] The group of components arranged on the first surface 51a of the circuit board includes three groups: common devices, transmitting devices, and receiving devices. Common devices include, for example, antennas and switches. Transmitting devices include, for example, power amplifiers (PAs) and matching circuits. Receiving devices include, for example, low noise amplifiers (LNAs) and matching circuits. Components belonging to these three groups are each mounted in a separate area.

[0018] As shown in Figure 1, the first substrate 51 has a second substrate surface 51b, which is the surface opposite to the first substrate surface 51a. Components 35 and the like are mounted on the second substrate surface 51b. A sealing resin 6b is arranged to cover the second substrate surface 51b and the sides of the components 35. In this example, the surface of the component 35 furthest from the second substrate surface 51b is exposed from the sealing resin 6b. Here, an example is shown where the surface of the component 35 furthest from the second substrate surface 51b is exposed from the sealing resin 6b, but the surface of the component 35 furthest from the second substrate surface 51b may also be covered by the sealing resin 6b.

[0019] Multiple connecting conductors 7 are connected to the second surface 51b of the substrate. The connecting conductors 7 are, for example, columnar conductors. The connecting conductors 7 are arranged to penetrate the sealing resin 6b. One end of each connecting conductor 7 is electrically connected to the second surface 51b of the substrate. The side of the connecting conductor 7 that is farther from the second surface 51b of the substrate is exposed from the sealing resin 6b.

[0020] Figures 3 and 4 show the metal foil 15 and the bonding material 16 after they have been removed. The metal foil 15 may be a single sheet, as shown in Figure 3. In the example shown in Figure 3, the metal foil 15 does not have a slit. A cross-sectional view of it from the side is shown in Figure 4. The bonding material 16 is placed on top of the metal foil 15. In Figure 3, the bonding material 16 is hidden behind the metal foil 15 on the paper, so it is not visible.

[0021] In this embodiment, the metal foil 15 is arranged to cover at least a portion of the first surface 31f of the inductor perpendicular to the winding shaft 31x, and the metal foil 15 is grounded. Therefore, the metal foil 15 acts as a shielding member and can efficiently block magnetic field lines generated from the inductor 31. Consequently, the shielding performance for the inductor can be enhanced without degrading the characteristics of the mounted inductor.

[0022] In particular, when shielding performance is important, the metal foil 15 and bonding material 16 are preferably configured as shown in this embodiment. That is, the metal foil 15 is preferably a single sheet without any openings.

[0023] As shown in this embodiment, by arranging the metal foil 15 as a shielding member in close proximity to the inductor 31, it becomes possible to more reliably shield the inductor, which requires the most shielding in the module's matching circuit. The matching circuit includes capacitors in addition to inductors, but among the components in the matching circuit, the inductor is the one that requires the most shielding.

[0024] In this embodiment, an example is shown in which no shield film is placed on the outer surface of the sealing resin 6a, but a shield film may be placed on the outer surface of the sealing resin 6a. For example, the shield film may be placed so as to cover any of the areas of the top surface and side surfaces of the sealing resin 6a, or the side surfaces of the sealing resin 6b.

[0025] In this embodiment, as an example, the first inductor surface 31f perpendicular to the winding axis 31x is described as a side surface of the inductor 31. However, this is merely an example, and the first inductor surface 31f is not always a side surface. Depending on the structure of the coil wiring 31c, the winding axis 31x may be in a different direction, so the first inductor surface 31f may be a surface other than the side surface of the inductor 31. In that case, it is preferable to arrange the metal foil 15 so as to cover at least a portion of that surface. Alternatively, it is preferable to arrange the metal foil 15 so as to cover at least a portion of the area including the point where the extension of the winding axis 31x intersects the first inductor surface 31f.

[0026] As shown in this embodiment, the first surface 31f of the inductor may be the surface of the inductor 31 that is farther from the first surface 51a of the substrate, or it may be a side surface of the inductor 31.

[0027] In this embodiment, an example is shown in which the first surface 51a of the substrate has a first recess 12 and the inductor 31 is mounted inside the first recess 12. However, the presence of the first recess 12 is not essential. The inductor 31 may be mounted in a region of the first surface 51a of the substrate that is not a recess. If the inductor 31 is the tallest component among the components mounted on the first surface 51a of the substrate, the overall height of the module can be reduced by providing the first recess 12 and mounting the inductor 31 inside the first recess 12.

[0028] (Embodiment 2) A module in Embodiment 2 based on the present invention will be described with reference to Figures 5 to 10. A cross-sectional view of module 102 in this embodiment is shown in Figure 5. A plan view of module 102 is shown in Figure 6. However, Figure 6 is the same as Figure 2 shown in Embodiment 1 in that it shows the state with the sealing resin 6a removed for the sake of explanation.

[0029] The basic configuration of module 102 is the same as that of module 101 shown in Embodiment 1. Module 102 differs from module 101 in that the metal foil 15 is not a single piece but includes two pieces of metal foil. As shown in Figures 5 and 6, the metal foil 15 includes metal foils 15a and 15b and an insulating material 17. The metal foils 15a and 15b are laminated with the insulating material 17 sandwiched in between. Since the insulating material 17 is sandwiched between the metal foils 15a and 15b, it is actually a three-layer structure, but if we focus on the metal part, there are two pieces of metal foil, so in the following, this structure will be referred to as a "two-layer structure". The two-layer structure of metal foil 15 formed by lamination in this way is attached to the side surface of the inductor 31 via a bonding material 16.

[0030] Figures 7 and 8 show the metal foils 15a and 15b, which are components of the metal foil 15, taken out individually.

[0031] As shown in Figure 7, the metal foil 15a has a cutout portion 18a. The cutout portion 18a is comb-shaped. The cutout portion 18a includes a linear first portion 18a1 and a plurality of parallel second portions 18a2 extending from the first portion 18a1. The plurality of parallel second portions 18a2 are perpendicular to the first portion 18a1.

[0032] As shown in Figure 8, the metal foil 15b has a cutout portion 18b. The cutout portion 18b is comb-shaped. The cutout portion 18b includes a linear third portion 18b3 and a plurality of parallel fourth portions 18b4 extending from the third portion 18b3. The plurality of parallel fourth portions 18b4 are perpendicular to the third portion 18b3. As shown in Figure 9, the metal foils 15a and 15b sandwich the insulating material 17. Figure 10 shows this state in a plan view. In Figure 10, the metal foil 15b is visible in the foreground, and the metal foil 15a is hidden behind the metal foil 15b. The cutout portion 18b provided on the metal foil 15b is visible in the foreground and is therefore shown with a solid line. The cutout portion 18a provided on the metal foil 15a is hidden by the metal foil 15b and is therefore shown with a dashed line. As is clear from Figure 10, there are no direct overlapping areas between the cutouts 18a and 18b. The comb shape of the cutout 18b and the comb shape of the cutout 18a are arranged in opposite directions. The first portion 18a1 and the third portion 18b3 are parallel. The multiple parallel second portions 18a2 and the multiple parallel fourth portions 18b4 are parallel and arranged alternately. The tips of the multiple parallel second portions 18a2 do not reach the third portion 18b3. The tips of the multiple parallel fourth portions 18b4 do not reach the first portion 18a1. By overlapping the metal foils 15a and 15b in this arrangement, regions in the metal foil 15 where large eddy currents can be generated are eliminated, and furthermore, the metal foil 15 has no openings through which magnetic field lines can pass.

[0033] Note that the number of parallel second sections 18a2 is shown as four here, but this is merely an example, and other numbers may be used. Similarly, the number of parallel fourth sections 18b4 is shown as three here, but this is merely an example, and other numbers may be used.

[0034] The configuration of the metal foil 15 shown in this embodiment can also be expressed as follows. The metal foil 15 includes a structure in which a metal foil 15a as a first metal layer, an insulating material 17 as an insulating layer, and a metal foil 15b as a second metal layer are laminated in this order. The metal foil 15a as the first metal layer has first slits of a first geometric pattern that obstruct the path of eddy currents. The metal foil 15b as the second metal layer has second slits of a second geometric pattern that obstruct the path of eddy currents. The first metal layer and the second metal layer are in a positional relationship such that the first slits and the second slits do not overlap at any point.

[0035] Here, the cutout portion 18a is shown as an example of the first slit, and the cutout portion 18b is shown as an example of the second slit. The shapes of the first and second slits are not limited to those shown here, and various shapes are possible.

[0036] In this embodiment as well, the effects described in Embodiment 1 can be obtained. Furthermore, in this embodiment, the metal foil 15 attached to the inductor 31 has a two-layer structure of metal foils 15a and 15b, and each of the metal foils 15a and 15b has a slit that obstructs the path of eddy currents, and moreover, the metal foil 15 has no openings through which magnetic flux lines can pass, so that it is possible to prevent the generation of eddy currents in the metal foil 15.

[0037] If eddy currents are generated in the metal foil 15, these eddy currents will generate magnetic flux lines in the opposite direction to the direction of the inductor's magnetic flux lines, which will cancel out the magnetic flux lines of the inductor 31 and may cause a decrease in inductance. However, according to this embodiment, the generation of eddy currents in the metal foil 15 can be prevented, and a decrease in the inductance of the inductor 31 can be avoided.

[0038] (Variations of slit shape) Various shapes are possible for the first slit and the second slit provided in the first metal layer and the second metal layer, respectively, contained in the metal foil 15 attached to the inductor 31. Two variations will be described below.

[0039] (First Modification) A first modification of the module in this embodiment will be described with reference to Figures 11 to 13. In the first modification, the metal foil 15 includes the metal foil 15c shown in Figure 11 and the metal foil 15d shown in Figure 12. The metal foil 15c has a cutout portion 18c. The metal foil 15d has a cutout portion 18d. The cutout portion 18c is a set of multiple parallel lines. The cutout portion 18d is also a set of multiple parallel lines.

[0040] When metal foil 15c and metal foil 15d are superimposed, the result is as shown in Figure 13. In Figure 13, the metal foil 15d in the foreground is visible, so the cutout portion 18d is shown with a solid line. The cutout portion 18c provided on the metal foil 15c in the background is hidden by the metal foil 15d in the foreground and is therefore shown with a dashed line. As is clear from Figure 13, there are no places where the cutout portion 18c and the cutout portion 18d directly overlap. The cutout portion 18c and the cutout portion 18d are parallel and arranged alternately, as shown in Figure 13.

[0041] In this configuration, shown as the first modified example, the effects described in Embodiment 1 can also be obtained. In particular, the metal foils 15c and 15d each have slits that obstruct the path of eddy currents, and the metal foil 15 has no openings through which magnetic flux lines can pass, so that eddy currents can not be generated in the metal foil 15.

[0042] (Second Modification) A second modification of the module in this embodiment will be described with reference to Figures 14 to 16. In the second modification, the metal foil 15 includes the metal foil 15e shown in Figure 14 and the metal foil 15f shown in Figure 15. The metal foil 15e has a cutout portion 18e. The metal foil 15f has a cutout portion 18f.

[0043] The cutout portion 18e provided in the metal foil 15e is a set of four or more L-shaped slits. These L-shaped slits can be classified into four groups. The number of L-shaped slits belonging to each group is 1 or more. When the number of L-shaped slits belonging to each group is 2 or more, these L-shaped slits are arranged along a virtual line connecting one corner of the metal foil 15e and the center of the metal foil 15e. In the example shown in FIG. 14, two L-shaped slits belong to one group. Here, the number of L-shaped slits belonging to one group is 2, but this number is merely an example and may be other numbers. The L-shaped slits belonging to each group are arranged such that each side is parallel. In the example shown here, each individual L-shaped slit is provided such that the bending vertex faces the center of the metal foil 15e.

[0044] The cutout portion 18f provided in the metal foil 15f is a set of four or more L-shaped slits. These L-shaped slits can be classified into four groups. The number of L-shaped slits belonging to each group is 1 or more. When the number of L-shaped slits belonging to each group is 2 or more, these L-shaped slits are arranged along a virtual line connecting one corner of the metal foil 15e and the center of the metal foil 15e. In the example shown in FIG. 15, one L-shaped slit belongs to one group. Here, the number of L-shaped slits belonging to one group is 1, but this number is merely an example and may be other numbers. The L-shaped slits belonging to each group are arranged such that each side is parallel. In the example shown here, each individual L-shaped slit is provided such that the bending vertex faces the center of the metal foil 15f.

[0045] When the metal foils 15e and 15f are overlapped, it becomes as shown in FIG. 16. In FIG. 16, since the front metal foil 15f is visible, the cutout portion 18f is shown by a solid line. The cutout portion 18e provided in the rear metal foil 15e is hidden by the front metal foil 15f and is not visible, so it is shown by a dashed line. As is clear from FIG. 16, there is no place where the cutout portion 18e and the cutout portion 18f directly overlap. The L-shaped slits belonging to the cutout portion 18e and the L-shaped slits belonging to the cutout portion 18f are parallel and arranged alternately as shown in FIG. 16.

[0046] Even in this configuration shown as the second modification, the effects described in the first embodiment can be obtained. In particular, the metal foils 15e and 15f each have slits that inhibit the path of eddy currents, and moreover, as the metal foil 15, a state where there is no opening through which magnetic flux lines can pass anywhere is realized, so it is possible to prevent the generation of eddy currents in the metal foil 15.

[0047] (Embodiment 3) Referring to FIG. 17, the module according to Embodiment 3 of the present invention will be described. A cross-sectional view of the module 103 in the present embodiment is shown in FIG. 17. The basic configuration of the module 103 is the same as the configuration of the module 101 shown in the first embodiment. In the module 103, the shape and connection method of the metal foil 15 are different from those of the module 101.

[0048] As shown in FIG. 17, the upper part of the metal foil 15 is connected to the first inductor surface 31f of the inductor 31. In the present embodiment, since the winding axis 31x of the inductor 31 is parallel to the first substrate surface 51a, the first inductor surface 31f is the side surface of the inductor 31. The first recess 12 provided in the first substrate 51 has a side surface 12d. The lower part of the metal foil 15 is electrically connected to the side surface 12d. An electrode 23 is provided on the side surface 12d. The electrode 23 is a ground electrode. That is, the first recess 12 is provided on the first substrate surface 51a, the inductor 31 is mounted in the first recess 12, and the metal foil 15 is grounded by being connected to the side surface 12d of the first recess 12.

[0049] In this embodiment as well, the same effects as in the first embodiment can be obtained. Since the metal foil 15 only needs to be connected to the side surface 12d of the first recess 12 rather than the bottom surface, alignment becomes easier compared to connecting to the bottom surface, and a more reliable electrical connection can be made.

[0050] For example, the metal foil 15 may be processed such that the upper part of the metal foil 15 is joined to the first surface 31f of the inductor, while the lower part of the metal foil 15 is separated from the first surface 31f of the inductor. When mounting the inductor 31 onto the first substrate 51, the lower part of the metal foil 15 that is separated from the first surface 31f of the inductor may be pressed against the side surface 12d, thereby joining the lower part of the metal foil 15 to the side surface 12d.

[0051] (Embodiment 4) A module in Embodiment 4 based on the present invention will be described with reference to Figures 18 to 19. Figure 18 shows a cross-sectional view of module 104 in this embodiment. The basic configuration of module 104 is the same as that of module 103 shown in Embodiment 3. In module 104, the direction of the winding axis 31x is different from that of module 103, and consequently, the shape and connection method of the metal foil 15 are different.

[0052] As shown in Figure 18, in this embodiment, the winding axis 31x of the inductor 31 is perpendicular to the first surface 51a of the substrate, so the first surface 31f of the inductor is the upper surface of the inductor 31, that is, the surface furthest from the first surface 51a of the substrate. The upper part of the metal foil 15 is connected to the first surface 31f of the inductor 31.

[0053] In this embodiment, the metal foil 15 includes two metal layers laminated with an insulating material 17 in between. That is, in this embodiment, the metal foil 15 has a two-layer structure. This is merely an example, and the metal foil 15 may also have a configuration that includes only one metal layer.

[0054] As shown in Figure 18, the metal foil 15 includes metal foils 15a and 15b and an insulating material 17. In the metal foil 15, the insulating material 17, metal foil 15a, insulating material 17, and metal foil 15b are laminated in this order. The metal foil 15 is attached to the upper surface of the inductor 31 via a bonding material 16.

[0055] In this embodiment, the metal foil 15 includes a main body portion that covers the upper surface of the inductor 31 and a wiring portion that electrically connects the main body portion and the first substrate 51. In Figure 18, the portion overlapping the upper surface of the inductor 31 is the main body portion, and the portion extending along the right side of the inductor 31 is the wiring portion. Figure 19 shows the inductor 31 and its vicinity as seen from the right side in Figure 18. When viewed from this orientation, if the inductor 31 and the metal foil 15 were to be represented by solid lines, other components to the right of the inductor 31 should also be represented by solid lines in the same way. However, in Figure 19, for the sake of explanation, components other than the inductor 31 are omitted from the illustration. In addition, the external terminals of the inductor 31 provided on the lower surface of the inductor 31 and the electrodes 24 provided on the upper surface of the first substrate 51 should not be visible in reality, but in Figure 19, the electrodes 24 are also shown for the sake of explanation.

[0056] In Figure 19, the wiring portion of the metal foil 15 is visible. The wiring portion extends in a strip shape with a constant width. The width of the wiring portion may be narrower than the width of the inductor 31. In the wiring portion, the metal foils 15a and 15b are each strip-shaped. In the wiring portion, the metal foils 15a and 15b do not overlap and extend at different positions in the width direction. The lower end of the wiring portion is connected to the side surface 12d of the first recess 12. An electrode 23a is provided on the bottom surface of the first recess 12. An electrode 23b is provided on the side surface 12d of the first recess 12. Electrodes 23a and 23b are each ground electrodes. At the lower end of the wiring portion, the metal foil 15a is electrically connected to electrode 23a, and the metal foil 15b is electrically connected to electrode 23b.

[0057] Note that in Figure 19, electrode 23a, which is provided on the bottom surface of the first recess 12, is shown, but electrode 23b is not. This is because electrode 23b is provided on the side surface 12d of the first recess 12, not the bottom surface. In Figure 19, electrode 23b is electrically connected to the metal foil 15b, located near the lower end of the wiring portion of the metal foil 15b, and positioned on the front side of the paper relative to the metal foil 15b. Therefore, electrode 23b is not visible in Figure 19.

[0058] In this embodiment as well, the same effects as in Embodiment 1 can be obtained. In this embodiment, an example is shown in which the metal foil 15 has a double-layered structure. In this case, it was necessary to connect both metal foils 15a and 15b contained in the metal foil 15 to the ground electrode, so electrodes were provided on the bottom and side surfaces of the first recess 12. However, if the metal foil 15 is a single piece rather than a double-layered structure, it is sufficient to provide electrodes only on the side surfaces as shown in Embodiment 3.

[0059] (Embodiment 5) Referring to Figure 20, a module in Embodiment 5 according to the present invention will be described. Figure 20 shows a cross-sectional view of module 105 in this embodiment. The basic configuration of module 105 is the same as that of module 101 shown in Embodiment 1. In module 105, the width of the first recess 12 is different from that of module 101, and consequently, the shape and connection method of the metal foil are different. In this embodiment, not only the inductor 31 but also components 32 and 33 are mounted inside the first recess 12. Here, metal foil 15r is used. The metal foil 15r includes a main body and a wiring part.

[0060] In this embodiment, since the winding axis 31x of the inductor 31 is parallel to the first surface 51a of the substrate, the first surface 31f of the inductor is the left side of the inductor 31 in the figure. The main body of the metal foil 15r is connected to the side surface of the inductor 31, which is the first surface 31f of the inductor. The wiring portion of the metal foil 15r extends along the top surface of the inductor 31 and is further connected to the side surface 12d via the top of components 32 and 33. In this case, the wiring portion of the metal foil 15r may be about the same width as the main body, or it may be narrower, as shown in Figure 19. Alternatively, the width of the wiring portion of the metal foil 15r may be wider than the width of the inductor 31. The metal foil 15r may be configured to cover a desired area on the first surface 51a of the substrate all at once. The desired area here may be, for example, an area corresponding to one of the three groups of common devices, transmitting devices, and receiving devices described in Embodiment 1. Among these three groups, the receiving device is particularly susceptible to noise interference, so it is preferable that the metal foil 15r covers the area corresponding to the receiving device all at once.

[0061] In this embodiment as well, the same effects as in the first embodiment can be obtained. In this embodiment, the inductor 31 and other components can be shielded together. Even if the inductor 31 and the side surface 12d of the first recess 12 are separated and the electrode 23 is provided on the side surface 12d, if a configuration is adopted in which the wiring section is long and can be arranged across other components 32 and 33, as in this embodiment, an electrical connection to the electrode 23 can be made.

[0062] In this embodiment, the metal foil 15r is shown as a single sheet, but the metal foil 15r may also have a two-layer structure as described in Embodiment 2.

[0063] One preferred configuration can be described as follows. In the preferred configuration of the module in this embodiment, multiple components are mounted on the first surface 51a of the substrate in addition to the inductor 31. The group consisting of all components, including the inductor 31 mounted on the first surface 51a of the substrate, includes a group of receiving devices 0073, and the metal foil 15 is arranged to cover all components belonging to the group of receiving devices collectively. By adopting this configuration, receiving devices that are susceptible to noise interference can be shielded collectively by the metal foil 15.

[0064] (Embodiment 6) A module in Embodiment 6 according to the present invention will be described with reference to Figure 21. A cross-sectional view of module 106 in this embodiment is shown in Figure 21. Module 106 includes a second substrate 52 in addition to the first substrate 51. The second substrate 52 is spaced apart from the first substrate 51 and arranged parallel to the first substrate 51. The second substrate 52 has a first substrate surface 52a and a second substrate surface 52b. The first substrate surface 51a of the first substrate 51 and the second substrate surface 52b of the second substrate 52 face each other. A structure combining two substrates in this way is sometimes called a "two-story structure" or "two-story substrate structure".

[0065] On the first surface 51a of the first substrate 51, components 33 and 34 are mounted in addition to the inductor 31. On the first surface 52a of the second substrate 52, components 32, 35, 36, etc. are mounted. The first surface 52a of the substrate and the components 32, 35, 36, etc. mounted on this surface are covered with sealing resin 6b.

[0066] The second surface 52b of the second substrate 52 has a second recess 13. A portion of the inductor 31 mounted on the first substrate 51 may be embedded in the second recess 13. The second recess 13 has a side surface 13d and a bottom surface 13e. A sealing resin 6a is placed between the first surface 51a of the first substrate 51 and the second surface 52b of the second substrate 52. The inductor 31, components 33, 34, etc. mounted on the first surface 51a are sealed by the sealing resin 6a. A connecting conductor 9 is placed to electrically connect the first surface 51a of the first substrate 51 and the second surface 52b of the second substrate 52. The connecting conductor 9 is placed so as to penetrate the sealing resin 6a.

[0067] A metal foil 15 is bonded to at least a portion of the first inductor surface 31f of the inductor 31 via an adhesive 16. In this embodiment, the winding axis 31x of the inductor 31 is oriented parallel to the first substrate surface 51a of the first substrate 51. Therefore, the first inductor surface 31f is the side surface of the inductor 31. The end of the metal foil 15 closer to the first substrate 51 is bonded to the first inductor surface 31f, while the end closer to the second substrate 52 is bonded to the side surface 13d of the second recess 13.

[0068] The metal foil 15 has a two-layer structure including metal foils 15a and 15b, similar to that shown in Embodiment 2. An electrode 23a is provided on the bottom surface 13e of the second recess 13. An electrode 23b is provided on the side surface 13d of the second recess 13. Electrodes 23a and 23b are ground electrodes. Metal foil 15a is electrically connected to electrode 23a, and metal foil 15b is electrically connected to electrode 23b.

[0069] The configuration of module 106 in this embodiment can be summarized as follows:

[0070] In this embodiment, the module 106 includes a second substrate 52 arranged parallel to and spaced apart from the first substrate 51. A second recess 13 is provided in the region of the second substrate 52 that includes the projection area of ​​the inductor 31. The metal foil 15 is grounded by being connected to the side or bottom surface of the second recess 13.

[0071] Even with a two-story structure like module 106 in this embodiment, the metal foil 15 is arranged to cover at least a portion of the first surface 31f of the inductor, so that magnetic field lines generated from the inductor 31 can be efficiently blocked. Therefore, the shielding performance for the inductor can be enhanced without degrading the characteristics of the mounted inductor.

[0072] In this embodiment, the first surface 31f of the inductor covered by the metal foil 15 faces inward rather than outward of the module 106, so that magnetic flux lines generated from the inductor 31 mainly toward other components 33, 34, etc. inside the module 106 can be efficiently blocked. A second recess 13 is provided in the second substrate 52, and a part of the inductor 31 is positioned to fit into the second recess 13, so the overall height of the module 106 can be reduced.

[0073] In this embodiment, an example in which the metal foil 15 has a double-layered structure has been described, but this is merely an example, and the metal foil 15 may be a single piece. As shown in this embodiment, when the metal foil 15 has a double-layered structure, it was necessary to connect both the metal foils 15a and 15b contained in the metal foil 15 to the ground electrode. Therefore, electrodes 23a and 23b were provided on the bottom surface 13e and side surface 13d of the second recess 13, and each was electrically connected separately. However, when the metal foil 15 is a single piece rather than a double-layered structure, an electrode may be provided on the side surface 13d of the second recess 13, and the connection may be made simply to this electrode.

[0074] Furthermore, if the metal foil 15 has a double-layered structure, the electrode 23a may be provided on the first surface 51a of the first substrate 51 instead of on the bottom surface 13e of the second recess 13.

[0075] Furthermore, when attempting to mount an inductor 31 inside a recess provided on the surface of the first substrate 51, the problem arises of how accurately the bottom surface of the recess can be made flat. If the bottom surface of the recess is not flat, mounting the inductor 31 becomes difficult. However, if a second recess 13 is provided on the second substrate 52 as in this embodiment, the inductor 31 is not mounted on the bottom surface of the second recess 13, making the formation of the second recess 13 easier. Even if the bottom surface of the second recess 13 is not perfectly flat, there is no problem in mounting the inductor 31 onto the first substrate 51.

[0076] (Embodiment 7) Referring to Figure 22, a module in Embodiment 7 according to the present invention will be described. Figure 22 shows a cross-sectional view of module 107 in this embodiment. Module 107 has a two-story structure, similar to module 106 described in Embodiment 6.

[0077] The second surface 52b of the second substrate 52 has a second recess 13. A portion of the inductor 31 mounted on the first substrate 51 may be embedded in the second recess 13. The second recess 13 has a side surface 13d and a bottom surface 13e. An electrode 23a is provided on the side surface 13d. An electrode 23b is provided on the bottom surface 13e.

[0078] In module 107, unlike module 106 described in Embodiment 6, the winding axis 31x of the inductor 31 is oriented perpendicular to the first surface 51a of the first substrate 51. Therefore, the first surface 31f of the inductor is the upper surface of the inductor 31. A portion of the metal foil 15, including one end, is joined to the first surface 31f of the inductor via a bonding material 16. The metal foil 15 may be joined so as to cover the entire first surface 31f of the inductor. The other end of the metal foil 15 is joined to the bottom surface 13e of the second recess 13. The other end of the metal foil 15 is electrically connected to an electrode 23 provided on the bottom surface 13e of the second recess 13. Multiple electrodes 23 may be provided on the bottom surface 13e. The same applies to the connection with these electrodes 23 as described in Embodiment 6.

[0079] The metal foil 15 has a two-layer structure including metal foils 15a and 15b, similar to that shown in Embodiment 2. An electrode 23a is provided on the side surface 13d of the second recess 13. An electrode 23b is provided on the bottom surface 13e of the second recess 13. Electrodes 23a and 23b are ground electrodes. Metal foil 15a is electrically connected to electrode 23a, and metal foil 15b is electrically connected to electrode 23b.

[0080] The configuration of the other parts of module 107 is the same as that described with respect to module 106 in Embodiment 6.

[0081] Even with a two-story structure like module 107 in this embodiment, the metal foil 15 is arranged to cover at least a portion of the first surface 31f of the inductor, so that magnetic field lines generated from the inductor 31 can be efficiently blocked. Therefore, the shielding performance for the inductor can be enhanced without degrading the characteristics of the mounted inductor.

[0082] In this embodiment, the first surface 31f of the inductor covered by the metal foil 15 faces the second substrate 52 rather than the outside of the module 107, so that magnetic flux lines generated from the inductor 31 towards components 32 mounted on the second substrate 52 can be efficiently blocked. A second recess 13 is provided in the second substrate 52, and a part of the inductor 31 is positioned to fit into the second recess 13, so the overall height of the module 107 can be reduced.

[0083] In this embodiment, an example in which the metal foil 15 has a double-layered structure has been described, but this is merely an example, and the metal foil 15 may be a single piece. As shown in this embodiment, when the metal foil 15 has a double-layered structure, it was necessary to connect both the metal foils 15a and 15b contained in the metal foil 15 to the ground electrode. Therefore, electrodes 23a and 23b were provided on the side surface 13d and bottom surface 13e of the second recess 13, and each was electrically connected separately. However, when the metal foil 15 is a single piece rather than a double-layered structure, an electrode may be provided on the bottom surface 13e of the second recess 13, and the connection may be made simply to this electrode.

[0084] Furthermore, multiple embodiments of the above-described embodiments may be used in appropriate combinations. The embodiments disclosed herein are illustrative in all respects and are not restrictive. The scope of the present invention is defined by the claims, including all modifications within the meaning and scope of the claims.

[0085] 6a, 6b Sealing resin, 7, 9 Connecting conductors, 12 First recess, 12d Side surface, 13 Second recess, 13d Side surface, 13e Bottom surface, 15, 15a, 15b, 15r Metal foil, 16 Bonding material, 17 Insulating material, 18a, 18b Cutouts, 18a1 First part, 18a2 Second part, 18b3 Third part, 18b4 Fourth part, 23, 23a, 23b, 24 Electrodes, 31 Inductor, 31f First surface of inductor, 31c Coil wiring, 31x Winding shaft, 32, 33, 34, 35, 36 Components, 51 First substrate, 51a First surface of substrate, 51b Second surface of substrate, 52 Second substrate, 52a, 52b Surface, modules 101, 102, 103, 104, 105, 106, 107.

Claims

1. A module comprising: a first substrate having a first substrate surface; an inductor having a winding shaft and mounted on the first substrate surface; and a sealing resin disposed to cover the inductor and the first substrate surface, wherein the inductor has an inductor first surface perpendicular to the winding shaft, a metal foil is disposed to cover at least a portion of the area of ​​the inductor first surface, and the metal foil is grounded.

2. The module according to claim 1, wherein the first surface of the inductor is the surface of the inductor that is farther from the first surface of the substrate, or the side surface of the inductor.

3. The module according to claim 1 or 2, wherein a first recess is provided on the first surface of the substrate, the inductor is mounted in the first recess, and the metal foil is grounded by being connected to the side surface of the first recess.

4. The module according to any one of claims 1 to 3, comprising a second substrate arranged parallel to and spaced apart from the first substrate, wherein a second recess is provided in a region of the second substrate including the projection region of the inductor, and the metal foil is grounded by being connected to the side or bottom surface of the second recess.

5. The module according to any one of claims 1 to 4, wherein the metal foil has a structure in which a first metal layer, an insulating layer, and a second metal layer are laminated in this order, the first metal layer has first slits of a first geometric pattern that obstruct the path of eddy currents, the second metal layer has second slits of a second geometric pattern that obstruct the path of eddy currents, and the first metal layer and the second metal layer are in a positional relationship such that the first slits and the second slits do not overlap at any point.

6. The module according to any one of claims 1 to 5, wherein a plurality of components other than the inductor are mounted on the first surface of the substrate, the group consisting of all components including the inductor mounted on the first surface of the substrate includes a group of receiving devices, and the metal foil is arranged to cover all components belonging to the group of receiving devices collectively.

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