JP6536539B2 - Electronic circuit package using composite magnetic sealing material - Google Patents

Description

  The present invention relates to an electronic circuit package, and more particularly to an electronic circuit package using a composite magnetic material as a mold material.

  In recent years, high-performance wireless communication circuits and digital chips have been adopted for electronic devices such as smart phones, and the operating frequency of the semiconductor IC to be used tends to rise. Furthermore, system-in-package (SIP) integration with a 2.5D structure or 3D structure in which a plurality of semiconductor ICs are connected by shortest wiring is accelerated, and modularization of power supply circuits is expected to increase in the future. Furthermore, modularization of a large number of electronic components (passive components such as inductors, capacitors, resistors, and filters, active components such as transistors and diodes, integrated circuit components such as semiconductor ICs, and other components necessary for the electronic circuit configuration) It is predicted that the number of electronic circuit modules will increase further in the future, and electronic circuit packages that collectively refer to these tend to be mounted at high density due to the high functionality, miniaturization, and thinning of electronic devices such as smartphones. These tendencies, on the other hand, indicate that malfunction and radio wave interference become noticeable due to noise, and it is difficult to prevent malfunction and radio wave interference with conventional noise countermeasures. For this reason, in recent years, the development of self shielding of electronic circuit packages has progressed, and proposals and practical applications of electromagnetic shielding by conductive paste or plating or sputtering have been made, but in the future, higher shielding properties are required.

  In order to realize this, in recent years, an electronic circuit package in which the mold material itself has a magnetic shielding property has been proposed. For example, Patent Document 1 discloses a composite magnetic sealing material to which a soft magnetic powder having an oxide film is added as a mold material for an electronic circuit package.

  However, the conventional composite magnetic sealing material has a problem that the thermal expansion coefficient is large. For this reason, a mismatch in thermal expansion coefficient occurs between the composite magnetic sealing material and the package substrate or the electronic component, and as a result, a large warp occurs in the state of an aggregate substrate having a strip shape after molding, or individualization After that, there is a case where a warp that is large enough to cause a problem in connectivity at the time of mounting reflow of the electronic circuit package is generated. Hereinafter, this phenomenon will be described.

  In recent years, various structures have been proposed and put to practical use in semiconductor packages and electronic component modules, but the current mainstream is to mount electronic components such as semiconductor ICs on an organic multilayer substrate and A structure molded by a resin sealing material is generally used. A semiconductor package or an electronic component module having such a structure is fabricated by molding in the state of a collective substrate and then singulated by dicing or the like.

  In this structure, since the organic multilayer substrate having different physical properties and the resin sealing material constitute a so-called bimetal, warpage occurs due to factors such as the difference in thermal expansion coefficient, glass transition, and cure shrinkage of the mold material. In order to suppress this, it is necessary to make physical properties, such as a thermal expansion coefficient, correspond as much as possible. In recent years, organic multilayer substrates used for semiconductor packages and electronic circuit modules tend to be increasingly thinner and multilayer due to the demand for lower height. While achieving this, use a substrate material with a high glass transition temperature or add a filler with a low coefficient of thermal expansion to the substrate material to achieve high rigidity and low thermal expansion to ensure thin substrate handling. It is common to use glass cloth which has a lower coefficient of thermal expansion.

  On the other hand, the physical property difference between the semiconductor IC and the electronic component mounted on the substrate and the mold material also causes stress, which causes various problems such as interfacial peeling of the mold material and cracks of the electronic component and the mold material. Silicon is used for the semiconductor IC, but the thermal expansion coefficient of silicon is 3.5 ppm / ° C., and the thermal expansion coefficient of fired chip parts such as ceramic capacitors and inductors is about 10 ppm / ° C.

  For this reason, low thermal expansion is also required for the molding material, and a material having a temperature of less than 10 ppm / ° C. is commercially available. As a method to lower the thermal expansion of the mold material, a method of blending fused silica with a very low thermal expansion coefficient of 0.5 ppm / ° C as well as using a low thermal expansion epoxy resin to the sealing resin at a high filling rate It is used.

Japanese Patent Application Laid-Open No. 10-64714

  On the other hand, general magnetic materials have a high thermal expansion coefficient. For this reason, as described in Patent Document 1, there is a problem that a composite magnetic sealing material in which a general soft magnetic powder is added to a mold resin can not achieve an intended low thermal expansion coefficient. The

  Therefore, an object of the present invention is to provide an electronic circuit package using a composite magnetic sealing material having a low thermal expansion coefficient as a mold material.

  The electronic circuit package according to the present invention comprises a substrate, an electronic component mounted on the surface of the substrate, and a magnetic mold resin covering the surface of the substrate so as to embed the electronic component, the magnetic mold resin being A resin material and a filler compounded in the resin material and having a compounding ratio of 30 to 85% by volume, wherein the filler contains 32 to 39% by weight of a metal material containing Ni as a main component in Fe. A filler is included, whereby the thermal expansion coefficient of the magnetic mold resin is 15 ppm / ° C. or less.

  According to the present invention, since the magnetic filler having a low thermal expansion coefficient is used, the thermal expansion coefficient of the magnetic mold resin made of the composite magnetic sealing material can be 15 ppm / ° C. or less. Therefore, it is possible to prevent warping of the substrate, peeling of the interface of the molding material, and cracking of the molding material.

  In the present invention, the metal material may further contain 0.1 to 8% by weight of Co based on the whole of the magnetic filler. According to this, it is possible to further reduce the thermal expansion coefficient of the magnetic mold resin made of the composite magnetic sealing material.

In the present invention, the filler may further contain a nonmagnetic filler. According to this, it is possible to further reduce the thermal expansion coefficient of the magnetic mold resin made of the composite magnetic sealing material. In this case, the amount of the nonmagnetic filler relative to the total of the magnetic filler and the nonmagnetic filler is preferably 1 to 40% by volume. According to this, it is possible to further reduce the thermal expansion coefficient of the magnetic mold resin made of the composite magnetic sealing material while securing sufficient magnetic properties. In this case, the nonmagnetic filler is selected from the group consisting of SiO ₂ , ZrW ₂ O ₈ , (ZrO) ₂ P ₂ O ₇ , KZr ₂ (PO ₄ ) ₃ and Zr ₂ (WO ₄ ) (PO ₄ ) _2. It is preferred to include at least one material. Since these materials have very low thermal expansion coefficients or negative values, it is possible to further reduce the thermal expansion coefficients of the magnetic mold resin comprising the composite magnetic sealing material.

  In the present invention, the shape of the magnetic filler is preferably approximately spherical. According to this, it is possible to increase the ratio of the magnetic filler in the composite magnetic sealing material.

In the present invention, the surface of the magnetic filler is preferably insulating coated, and the thickness of the insulating coating is more preferably 10 nm or more. According to this, it is possible to increase the volume resistivity of the magnetic mold resin made of the composite magnetic sealing material to, for example, 10 ¹⁰ Ω · cm or more, and to secure the insulation property required for the mold material for the electronic circuit package. It becomes possible.

  In the present invention, the resin material is preferably a thermosetting resin material, and the thermosetting resin material is at least one selected from the group consisting of an epoxy resin, a phenol resin, a urethane resin, a silicone resin and an imide resin. It is preferred to include two materials.

  The electronic circuit package according to the present invention may further include a nonmagnetic member provided between the electronic component and the magnetic mold resin. According to this, it is possible to suppress the fluctuation of the characteristics of the electronic component and the like due to the proximity of the electronic component and the magnetic mold resin.

  The electronic circuit package according to the present invention preferably further comprises a metal film which is connected to a power supply pattern provided on the substrate and which covers the magnetic mold resin. According to this, it is possible to obtain a composite shield structure having both an electromagnetic shielding function and a magnetic shielding function.

  In this case, the metal film preferably contains at least one metal selected from the group consisting of Au, Ag, Cu and Al as a main component, and the surface of the metal film is covered with an anti-oxidation coating. Is more preferred. Preferably, the power supply pattern is exposed on the side surface of the substrate, and the metal film is in contact with the power supply pattern exposed on the side surface of the substrate. According to this, it is possible to easily and reliably connect the metal film to the power supply pattern.

  As described above, the electronic circuit package according to the present invention uses magnetic mold resin having a small thermal expansion coefficient as a mold material, so that warpage of the substrate, peeling of the interface of the mold material, molding material can be obtained while securing the magnetic shield characteristics. Cracks and the like can be prevented.

FIG. 1 is a cross-sectional view showing the configuration of an electronic circuit package according to a first embodiment of the present invention. FIG. 2 is a cross-sectional view showing the configuration of an electronic circuit package according to a modification of the first embodiment. FIG. 3 is a process diagram for explaining a method of manufacturing the electronic circuit package shown in FIG. FIG. 4 is a process diagram for explaining a method of manufacturing the electronic circuit package shown in FIG. FIG. 5 is a process diagram for explaining a method of manufacturing the electronic circuit package shown in FIG. FIG. 6 is a schematic view for explaining the configuration of the composite magnetic sealing material. FIG. 7 is a graph showing the relationship between the Ni ratio of the magnetic filler and the thermal expansion coefficient and the magnetic permeability of the composite magnetic sealing material. FIG. 8 is a graph showing the relationship between the Ni ratio of the magnetic filler and the thermal expansion coefficient of the composite magnetic sealing material. FIG. 9 is a graph showing the relationship between the Ni ratio of the magnetic filler and the magnetic permeability of the composite magnetic sealing material. FIG. 10 is a graph showing the relationship between the Co ratio of the magnetic filler and the thermal expansion coefficient and the magnetic permeability of the composite magnetic sealing material. FIG. 11 is a graph showing the relationship between the addition ratio of nonmagnetic filler and the thermal expansion coefficient of the composite magnetic sealing material. FIG. 12 is a graph showing the relationship between the presence or absence of an insulating coating formed on the surface of the magnetic filler and the volume resistivity. FIG. 13 is a graph showing the relationship between the film thickness of the insulating coat formed on the surface of the magnetic filler and the volume resistivity. FIG. 14 is a graph showing the relationship between the volume resistivity of the magnetic filler and the volume resistivity of the composite magnetic sealing material. FIG. 15 is a cross-sectional view showing the configuration of the electronic circuit package according to the second embodiment of the present invention. FIG. 16 is a process diagram for illustrating a method of manufacturing the electronic circuit package shown in FIG. FIG. 17 is a process diagram for illustrating a method of manufacturing the electronic circuit package shown in FIG. FIG. 18 is a process diagram for illustrating a method of manufacturing the electronic circuit package shown in FIG. FIG. 19 is a cross-sectional view showing the configuration of the electronic circuit package according to the third embodiment of the present invention. FIG. 20 is a cross-sectional view showing the configuration of an electronic circuit package according to a first modification of the third embodiment. FIG. 21 is a cross-sectional view showing a configuration of an electronic circuit package according to a second modification of the third embodiment. FIG. 22 is a cross-sectional view showing the configuration of an electronic circuit package according to a third modification of the third embodiment. FIG. 23 is a cross-sectional view showing a configuration of an electronic circuit package according to a fourth modification of the third embodiment. FIG. 24 is a graph showing the amount of noise attenuation of the electronic circuit package shown in FIG. FIG. 25 is a graph showing the relationship between the film thickness of the metal film included in the electronic circuit package shown in FIG. 19 and the amount of noise attenuation. FIG. 26 is a graph showing the relationship between the film thickness of the metal film included in the electronic circuit package shown in FIG. 19 and the amount of noise attenuation. FIG. 27 is a graph showing the relationship between the thickness of the metal film included in the electronic circuit package shown in FIG. 19 and the amount of noise attenuation. FIG. 28 is a graph showing the amount of warping of the substrate at the time of temperature rise and fall of the electronic circuit package shown in FIGS. 1 and 19. FIG. 29 is a graph showing the amount of warp of the substrate at the time of temperature rise and fall of the electronic circuit package in the comparative example. FIG. 30 is a cross-sectional view showing the configuration of the electronic circuit package according to the fourth embodiment of the present invention. FIG. 31 is a process diagram for illustrating a method of manufacturing the electronic circuit package shown in FIG. FIG. 32 is a process diagram for illustrating a method of manufacturing the electronic circuit package shown in FIG. FIG. 33 is a table showing composition 1 to composition 3. FIG. 34 is a table showing measurement results of the example. FIG. 35 is a table showing measurement results of the example.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

First Embodiment
FIG. 1 is a cross-sectional view showing the configuration of an electronic circuit package 11A according to a first embodiment of the present invention.

  As shown in FIG. 1, the electronic circuit package 11A according to the present embodiment includes a substrate 20, a plurality of electronic components 31 and 32 mounted on the substrate 20, and a surface 21 of the substrate 20 so as to embed the electronic components 31 and 32. And a magnetic mold resin 40 for covering.

  The type of the electronic circuit package 11A according to the present embodiment is not particularly limited. For example, a high frequency module that handles high frequency signals, a power supply module that performs power control, and a system in package (SIP) having a 2.5D structure or 3D structure And semiconductor packages for wireless communication or digital circuits. Although only two electronic components 31 and 32 are illustrated in FIG. 1, more electronic components are actually incorporated.

  The substrate 20 has a double-sided and multi-layered wiring structure in which a large number of wirings are embedded, and an organic substrate based on a thermosetting resin such as FR-4, FR-5, BT, cyanate ester, phenol, imide, There is no limitation on types such as organic resin substrates based on thermoplastic resins such as liquid crystal polymers, LTCC substrates, HTCC substrates, flexible substrates and the like. In the present embodiment, the substrate 20 has a four-layer structure, and includes wiring layers formed on the front surface 21 and the back surface 22 of the substrate 20, and two wiring layers embedded inside. A plurality of land patterns 23 are formed on the surface 21 of the substrate 20. The land pattern 23 is an internal electrode for connecting to the electronic components 31 and 32, and both are electrically and mechanically connected via the solder 24 (or conductive paste). As an example, the electronic component 31 is a semiconductor chip such as a controller, and the electronic component 32 is a passive component such as a capacitor or a coil. A part of the electronic component (for example, a thinned semiconductor chip or the like) may be embedded in the substrate 20.

  The land pattern 23 is connected to an external terminal 26 formed on the back surface 22 of the substrate 20 through an internal wiring 25 formed inside the substrate 20. In actual use, the electronic circuit package 11A is mounted on a motherboard (not shown) or the like, and the land pattern on the motherboard and the external terminal 26 of the electronic circuit package 11A are electrically connected. As a material of the conductor which comprises the land pattern 23, the internal wiring 25, and the external terminal 26, metals, such as copper, silver, gold, nickel, chromium, aluminum, palladium, indium, or its metal alloy may be sufficient, and resin Alternatively, a conductive material containing glass as a binder may be used, but when the substrate 20 is an organic substrate or a flexible substrate, it is preferable to use copper or silver from the viewpoint of cost, conductivity, and the like. As a method of forming these conductive materials, methods such as printing, plating, foil lamination, sputtering, vapor deposition, and ink jet can be used.

The magnetic mold resin 40 is provided to cover the surface 21 of the substrate 20 so as to embed the electronic components 31 and 32. The magnetic mold resin 40 is a mold member and also functions as a magnetic shield. In the present embodiment, the side surface 42 of the magnetic mold resin 40 and the side surface 27 of the substrate 20 constitute the same plane. Although the details of the magnetic mold resin 40 will be described later, the magnetic mold resin 40 is made of a composite magnetic sealing material having a very small thermal expansion coefficient (eg, 15 ppm / ° C. or less) as compared to the conventional magnetic mold resin. Since the magnetic mold resin 40 is in contact with the electronic components 31 and 32 and the land pattern 23, its volume resistivity needs to be sufficiently high, and specifically, it is preferable to be 10 ¹⁰ Ω · cm or more.

  In the case of an electronic component such as a high frequency inductor, if the distance to the magnetic mold resin 40 is too short, the characteristics such as the inductance value may fluctuate from the design value. In such a case, the variation in characteristics can be reduced by covering a part or all of the electronic component with a nonmagnetic member. FIG. 2 is a cross-sectional view showing a configuration of an electronic circuit package 11B according to a modification, which differs from the electronic circuit package 11A shown in FIG. 1 in that the electronic component 32 is covered with a nonmagnetic member 50. . As the nonmagnetic member 50, general resin can be used. If such a nonmagnetic member 50 is interposed between the electronic component 32 and the magnetic mold resin 40, the distance between the electronic component 32 and the magnetic mold resin 40 is increased, so that the fluctuation of characteristics such as the inductance value is reduced. It becomes possible.

  Next, a method of manufacturing the electronic circuit package 11A according to the present embodiment will be described.

  3 to 5 are process diagrams for explaining the method of manufacturing the electronic circuit package 11A.

  First, as shown in FIG. 3, a collective substrate 20A having a multilayer wiring structure is prepared. A plurality of land patterns 23 are formed on the front surface 21 of the collective substrate 20A, and a plurality of external terminals 26 are formed on the back surface 22 of the collective substrate 20A. Further, a plurality of internal wirings 25 are formed in the inner layer of the collective substrate 20A. The broken line a shown in FIG. 3 indicates a portion to be cut in the subsequent dicing step.

  Next, as shown in FIG. 3, the plurality of electronic components 31 and 32 are mounted on the surface 21 of the collective substrate 20A so as to be connected to the land pattern 23. Specifically, after the solder 24 is supplied onto the land pattern 23, the electronic components 31 and 32 may be mounted, and the electronic components 31 and 32 may be connected to the land pattern 23 by reflow.

  Next, as shown in FIG. 4, the surface 21 of the collective substrate 20 </ b> A is covered with the magnetic mold resin 40 so as to embed the electronic components 31 and 32. As a method of forming the magnetic mold resin 40, a method using transfer molding, compression molding, injection molding, casting, vacuum casting, dispensing, a slit nozzle, or the like can be used.

  Then, as shown in FIG. 5, if the substrate 20 is separated by cutting the collective substrate 20A along the broken line a, the electronic circuit package 11A according to the present embodiment is completed.

  Next, the composite magnetic sealing material constituting the magnetic mold resin 40 will be described in detail.

  FIG. 6 is a schematic view for explaining the configuration of the composite magnetic sealing material constituting the magnetic mold resin 40. As shown in FIG.

  As shown in FIG. 6, the composite magnetic sealing material 2 constituting the magnetic mold resin 40 is composed of a resin material 4, and a magnetic filler 6 and a nonmagnetic filler 8 blended in the resin material 4. Although not particularly limited, the resin material 4 preferably contains a thermosetting resin material as a main component. Specifically, an epoxy resin, a phenol resin, a urethane resin, a silicone resin or an imide resin is preferably used as a main component, and a main agent and a curing agent used for an epoxy resin or a phenol resin-based semiconductor sealing material may be used. More preferable.

  Most preferable is an epoxy resin having a reactive epoxy group at the end, which can be combined with various curing agents and curing accelerators. Examples of epoxy resins include bisphenol A type, bisphenol F type, phenoxy, naphthalene, multifunctional type (such as dicyclopentadiene type), biphenyl type (bifunctional) and special structure type, and biphenyl capable of low thermal expansion, Naphthalene, dicyclopentadiene type and the like are useful. Examples of curing agents or curing accelerators include amine compounds alicyclic diamines, aromatic diamines, other amine compounds (imidazole, tertiary amines), acid anhydride compounds (mainly high-temperature curing agents), phenol resins (Novolak type, cresol novolac type, etc.), amino resin, dicyandiamide, Lewis acid complex compounds. As a method of kneading the material, a known method such as a kneader, three rolls, or a mixer may be appropriately used.

  The magnetic filler 6 is made of an Fe—Ni-based material, and contains 32 wt% or less and 39 wt% or less of a metal material containing Ni as a main component. The element that occupies the remaining 61 to 68% by weight is Fe. The compounding ratio of the magnetic filler 6 is 30% by volume or more and 85% by volume or less with respect to the entire composite magnetic sealing material 2. This is because it is difficult to obtain sufficient magnetic properties when the compounding ratio of the magnetic filler 6 is less than 30% by volume, and when the compounding ratio of the magnetic filler 6 exceeds 85% by volume, sealing such as fluidity is performed. It is because it is difficult to secure various properties required for the material.

  The metal material containing Ni as a main component may contain a small amount of Co. That is, part of Ni may be replaced by Co. According to this, the thermal expansion coefficient of the composite magnetic sealing material 2 can be further reduced. The addition amount of Co is preferably 0.1% by weight or more and 8% by weight or less based on the whole of the magnetic filler 6.

  The shape of the magnetic filler 6 is not particularly limited, but in order to achieve high packing, it may be spherical, and fillers of a plurality of particle size distributions may be blended and blended so as to achieve close packing. In addition, when the magnetic filler 6 has a substantially spherical shape, damage to the electronic component during molding can also be reduced. In particular, for close packing or high packing, it is preferable that the shape of the magnetic filler 6 is a true sphere. The magnetic filler 6 preferably has a high tap density and a small powder specific surface area. As a method of forming the magnetic filler 6, there are methods such as a water atomizing method, a gas atomizing method, a centrifugal disc atomizing method, etc. Among them, a gas atomizing method which can obtain a high tap density and can reduce the specific surface area is most preferable.

  Although not particularly limited, the surface of the magnetic filler 6 is an insulation made of an oxide of a metal such as Si, Al, Ti, Mg, or an organic material in order to improve fluidity, adhesion, and insulation. It is covered with a coat 7. In order to sufficiently increase the volume resistivity of the composite magnetic sealing material 2, the film thickness of the insulating coat 7 is preferably 10 nm or more. The insulating coating 7 may be coated with a thermosetting material on the surface of the magnetic filler 6, or may be formed into an oxide film by dehydration reaction of metal alkoxide of tetraethyloxysilane or tetramethyloxysilane, and a coated film of silicon oxide Formation is most preferred. Furthermore, it is more preferable to apply an organic functional coupling treatment thereon.

The composite magnetic sealing material 2 according to the present embodiment includes the nonmagnetic filler 8. As the nonmagnetic filler 8, it is more preferable than the magnetic filler 6 such as SiO ₂ , ZrW ₂ O ₈ , (ZrO) ₂ P ₂ O ₇ , KZr ₂ (PO ₄ ) ₃ or Zr ₂ (WO ₄ ) (PO ₄ ) ₂ It is preferable to use a material having a small thermal expansion coefficient or a material having a negative thermal expansion coefficient. If such a nonmagnetic filler 8 is added to the composite magnetic sealing material 2, the thermal expansion coefficient can be further reduced. In addition, flame retardants such as aluminum oxide and magnesium oxide, carbon black for coloring, pigments or dyes, surface-treated with a particle size of 100 nm or less to improve slipperiness, fluidity, and dispersion / mixability. Nano silica, or a wax component for improving releasability may be added. However, in the present invention, it is not essential that the composite magnetic sealing material constituting the magnetic mold resin 40 contains a nonmagnetic filler.

  Further, in order to improve adhesion and fluidity, the surface of the magnetic filler 6 and the nonmagnetic filler 8 may be subjected to an organic functional coupling treatment. The organic functional coupling treatment may be performed by a known wet or dry method, and may be an integral blend method. In addition, the surface of the magnetic filler 6 and the nonmagnetic filler 8 may be coated with a thermosetting resin to improve the wettability and the like.

  When nonmagnetic filler 8 is added, the amount of nonmagnetic filler 8 relative to the total of magnetic filler 6 and nonmagnetic filler 8 is preferably 1% by volume or more and 40% by volume or less. In other words, 1% by volume or more and 40% by volume or less of the magnetic filler 6 can be replaced with the nonmagnetic filler 8. This is because when the addition amount of the nonmagnetic filler 8 is less than 1% by volume, the effect of adding the nonmagnetic filler 8 can hardly be obtained, and when the addition amount of the nonmagnetic filler 8 exceeds 40% by volume, This is because the amount of the magnetic filler 6 is too small, and it becomes difficult to secure sufficient magnetic characteristics.

  The form of the composite magnetic sealing material 2 may be either liquid or solid, and the form is different depending on the selection of the main agent and the curing agent according to the molding method. The solid composite magnetic sealing material 2 may be tablet-shaped for transfer molding, and may be granular-shaped for injection molding or compression molding. Further, as a molding method using the composite magnetic sealing material 2, transfer molding, compression molding, injection molding, casting, vacuum casting, vacuum printing, printing, dispensing, a method using a slit nozzle, etc. can be appropriately selected. it can. The molding conditions may be appropriately selected from the combination of the main agent to be used, the curing agent, and the curing accelerator, and after curing, after curing may be performed if necessary.

  FIG. 7 is a graph showing the relationship between the Ni ratio of the magnetic filler 6 and the thermal expansion coefficient and the magnetic permeability of the composite magnetic sealing material 2. The graph shown in FIG. 7 shows the case where the magnetic filler 6 consists essentially of Fe and Ni, and the addition amount of the magnetic filler 6 with respect to the entire composite magnetic sealing material 2 is 70% by volume, and the composite is The case where the nonmagnetic filler 8 is not added to the magnetic sealing material 2 is shown.

  As shown in FIG. 7, when the Ni ratio of the magnetic filler 6 is 32% by weight or more and 39% by weight or less, the thermal expansion coefficient of the composite magnetic sealing material 2 becomes specifically low, and 10 ppm / ° C. depending on the conditions. It becomes below. Under the conditions, the lowest thermal expansion coefficient (about 9.3 ppm / ° C.) is obtained when the Ni ratio is about 35% by weight. On the other hand, the magnetic permeability is small in correlation with the Ni ratio, and in the range of the Ni ratio shown in FIG.

  Such characteristics are obtained because when the Ni ratio is in the above-mentioned range, an inbar characteristic in which the volume change due to the thermal expansion and the magnetostriction offset each other is expressed. Such a material is called an invar material and is known as a material of a mold requiring high accuracy, but it has never been used as a material of a magnetic filler to be compounded in a composite magnetic sealing material. The present invention pays attention to the magnetic property and low thermal expansion coefficient of invar material, and by using this as a material of magnetic filler, a composite magnetic sealing material 2 having magnetic shielding property and small thermal expansion coefficient 2 Is realized.

  FIG. 8 is a graph showing the relationship between the Ni ratio of the magnetic filler 6 and the thermal expansion coefficient of the composite magnetic sealing material 2. The graph shown in FIG. 8 shows the case where the magnetic filler 6 substantially consists of only Fe and Ni, and the addition amount of the magnetic filler 6 with respect to the entire composite magnetic sealing material 2 is 50% by volume, 60% by volume or 70%. It is a volume%, and the case where the nonmagnetic filler 8 is not added to the composite magnetic sealing material 2 is shown.

  As shown in FIG. 8, even if the addition amount of the magnetic filler 6 is any of 50% by volume, 60% by volume and 70% by volume, the Ni ratio of the magnetic filler 6 is 32% by weight or more and 39% by weight or less In this case, it is understood that the thermal expansion coefficient of the composite magnetic sealing material 2 is specifically lowered. The value of the thermal expansion coefficient decreases as the amount of addition of the magnetic filler 6 increases. Therefore, when the addition amount of the magnetic filler 6 is small (for example, 30% by volume), the thermal expansion coefficient of the composite magnetic sealing material 2 is 15 ppm by further adding the nonmagnetic filler 8 made of fused silica or the like. The temperature should be less than / ° C. Specifically, if the total addition amount of the magnetic filler 6 and the nonmagnetic filler 8 is 50 volume% or more and 85 volume% or less of the whole, the thermal expansion coefficient of the composite magnetic sealing material 2 is sufficiently (for example, 15 ppm / Or less).

  FIG. 9 is a graph showing the relationship between the Ni ratio of the magnetic filler 6 and the magnetic permeability of the composite magnetic sealing material 2. Similar to the graph shown in FIG. 8, the graph shown in FIG. 9 shows the case where the magnetic filler 6 consists essentially of Fe and Ni, and the addition amount of the magnetic filler 6 is 50 with respect to the entire composite magnetic sealing material 2. It is a volume%, 60 volume%, or 70 volume%, and the case where the nonmagnetic filler 8 is not added to the composite magnetic sealing material 2 is shown.

  As shown in FIG. 9, it is understood that the correlation between the Ni ratio and the magnetic permeability is small regardless of the addition amount of the magnetic filler 6 being any of 50% by volume, 60% by volume and 70% by volume. The value of the magnetic permeability increases as the amount of addition of the magnetic filler 6 increases.

  FIG. 10 is a graph showing the relationship between the Co ratio of the magnetic filler 6 and the thermal expansion coefficient and the magnetic permeability of the composite magnetic sealing material 2. The graph shown in FIG. 10 shows that the sum of Ni and Co contained in the magnetic filler 6 is 37% by weight, and the addition amount of the magnetic filler 6 with respect to the entire composite magnetic sealing material 2 is 70% by volume, The case where the nonmagnetic filler 8 is not added to the composite magnetic sealing material 2 is shown.

  As shown in FIG. 10, compared with the case where Co is not contained in the magnetic filler 6 (Co = 0% by weight), when Ni constituting the magnetic filler 6 is replaced with Co at 8% by weight or less. The thermal expansion coefficient of the composite magnetic sealing material 2 is further reduced. However, when the amount of substitution by Co is 10% by weight, the thermal expansion coefficient is rather high. Therefore, the addition amount of Co is preferably 0.1% by weight or more and 8% by weight or less based on the whole of the magnetic filler 6.

FIG. 11 is a graph showing the relationship between the addition ratio of the nonmagnetic filler 8 and the thermal expansion coefficient of the composite magnetic sealing material 2. The graph shown in FIG. 11 shows that the sum of the magnetic filler 6 and the nonmagnetic filler 8 is 70% by volume, and the magnetic filler 6 consists of 64% by weight of Fe and 36% by weight of Ni, and the nonmagnetic filler 8 is It shows the case of SiO ₂ .

  As shown in FIG. 11, the coefficient of thermal expansion decreases as the proportion of nonmagnetic filler 8 increases, but when the proportion exceeds 40% by volume of nonmagnetic filler relative to 60% by volume of magnetic filler, the thermal expansion coefficient reducing effect Is almost saturated. Therefore, the amount of the nonmagnetic filler 8 is preferably 1% by volume or more and 40% by volume or less based on the total of the magnetic filler 6 and the nonmagnetic filler 8.

FIG. 12 is a graph showing the relationship between the presence or absence of the insulating coat 7 formed on the surface of the magnetic filler 6 and the volume resistivity. The materials of the magnetic filler 6 are two types of composition A (Fe = 64 wt%, Ni = 36 wt%) and composition B (Fe = 63 wt%, Ni = 32 wt%, Co = 5 wt%), The insulating coat 7 is SiO ₂ with a thickness of 40 nm. The magnetic filler 6 also has a cut diameter of 32 μm and a particle diameter D50 of 20 μm.

  As shown in FIG. 12, it can be seen that the volume resistivity of the magnetic filler 6 is significantly increased by coating with the insulating coat 7 in any of the composition A and the composition B. In addition, it can be seen that, when covered with the insulating coat 7, the pressure dependency at the time of measurement is also reduced.

  FIG. 13 is a graph showing the relationship between the film thickness of the insulating coat 7 formed on the surface of the magnetic filler 6 and the volume resistivity. The graph shown in FIG. 13 shows the case where the magnetic filler 6 is composed of 64% by weight of Fe and 36% by weight of Ni. The particle size of the magnetic filler 6 is the same as the particle size in FIG.

  As shown in FIG. 13, it can be seen that the volume resistivity of the magnetic filler 6 is significantly increased by covering the magnetic filler 6 with the insulating coating 7 of 10 nm or more. In particular, when the magnetic filler 6 is coated with the insulating coating 7 of 30 nm or more, it can be seen that a very high volume resistivity can be obtained regardless of the pressure at the time of measurement.

  FIG. 14 is a graph showing the relationship between the volume resistivity of the magnetic filler 6 and the volume resistivity of the composite magnetic sealing material 2.

As shown in FIG. 14, it can be seen that the volume resistivity of the magnetic filler 6 and the volume resistivity of the composite magnetic sealing material 2 are in a proportional relationship. In particular, when the volume resistivity of the magnetic filler 6 is 10 ⁵ Ω · cm or more, the volume resistivity of the composite magnetic sealing material 2 can be 10 ¹⁰ Ω · cm or more. When the volume resistivity of the composite magnetic sealing material 2 is 10 ¹⁰ Ω · cm or more, sufficient insulation can be secured when used as a mold material for an electronic circuit package.

  As described above, since the electronic circuit packages 11A and 11B according to the present embodiment use the composite magnetic sealing material 2 having a very small thermal expansion coefficient as the material of the magnetic mold resin 40, they have magnetic shield characteristics. In addition, it is possible to prevent the warping of the substrate, the interface peeling of the mold material, the crack of the mold material and the like due to the temperature change.

Second Embodiment
FIG. 15 is a cross-sectional view showing the configuration of the electronic circuit package 12A according to the second embodiment of the present invention.

  As shown in FIG. 15, in the electronic circuit package 12A according to the present embodiment, the planar size of the magnetic mold resin 40 is slightly smaller than the planar size of the substrate 20, whereby the outer peripheral portion of the surface 21 of the substrate 20 is a magnetic mold It differs from the electronic circuit package 11A according to the first embodiment shown in FIG. 1 in that the resin 40 is exposed. The other configuration is the same as that of the electronic circuit package 11A according to the first embodiment, and therefore the same components are denoted by the same reference numerals and redundant description will be omitted.

  As exemplified by the electronic circuit package 12A according to the present embodiment, in the present invention, it is not essential that the side surface 42 of the magnetic mold resin 40 and the side surface 27 of the substrate 20 constitute the same plane. It does not matter if it is smaller.

  16 to 18 are process diagrams for explaining the method of manufacturing the electronic circuit package 12A.

  First, as shown in FIG. 16, the substrate 20 cut in advance is prepared, and the plurality of electronic components 31 and 32 are mounted so as to be connected to the land pattern 23 on the surface 21 thereof. Specifically, after the solder 24 is supplied onto the land pattern 23, the electronic components 31 and 32 may be mounted, and the electronic components 31 and 32 may be connected to the land pattern 23 by reflow.

  Next, as shown in FIG. 17, the substrate 20 on which the electronic components 31 and 32 are mounted is set in the mold 80. Then, as shown in FIG. 18, the composite magnetic material, which is the material of the magnetic mold resin 40, is injected from the flow path 81 of the mold 80, and pressurization and heating are performed. Thus, the electronic circuit package 12A according to the present embodiment is completed.

  As described above, the magnetic mold resin 40 may be formed after the substrate 20 is singulated first.

Third Embodiment
FIG. 19 is a cross-sectional view showing the configuration of the electronic circuit package 13A according to the third embodiment of the present invention.

  As shown in FIG. 19, the electronic circuit package 13A according to the present embodiment further includes a metal film 60 covering the upper surface 41 and the side surface 42 of the magnetic mold resin 40 and the side surface 27 of the substrate 20. It differs from the electronic circuit package 11A according to the first embodiment shown in FIG. Further, among the internal wirings 25, the internal wirings 25 having G at the end of the reference numeral are power supply patterns, and a part thereof is exposed to the side surface 27 of the substrate 20. The power supply pattern 25G is typically a ground pattern to which a ground potential is applied, but it is not limited to the ground pattern as long as it is a pattern to which a fixed potential is applied. The other configuration is the same as that of the electronic circuit package 11A according to the first embodiment, and therefore the same components are denoted by the same reference numerals and redundant description will be omitted.

  The metal film 60 is an electromagnetic shield, and preferably contains at least one metal selected from the group consisting of Au, Ag, Cu and Al as a main component. The metal film 60 preferably has a resistance as low as possible, and in view of cost and the like, it is most preferable to use Cu. Further, the outer surface of the metal film 60 is covered with an anti-corrosion coating made of a corrosion-resistant metal such as SUS, Ni, Cr, Ti, or brass, or a resin such as epoxy, phenol, imide, urethane, or silicone. Is preferred. Since the metal film 60 is oxidatively degraded in the external environment such as heat and humidity, it is preferable to apply the above-mentioned treatment in order to suppress and prevent this. The method of forming the metal film 60 may be appropriately selected from known methods such as a sputtering method, a vapor deposition method, an electroless plating method, and an electrolytic plating method, and plasma treatment which is an adhesion improvement pretreatment before forming the metal film 60. , Coupling treatment, blasting treatment, etching treatment, etc. may be performed. Furthermore, as a base of the metal film 60, a high adhesion metal film such as titanium, chromium, or SUS may be thinly formed in advance.

  As shown in FIG. 19, the power supply pattern 25G is exposed on the side surface 27 of the substrate 20, and the metal film 60 is connected to the power supply pattern 25G by covering the side surface 27 of the substrate 20.

The resistance value at the interface between the metal film 60 and the magnetic mold resin 40 is preferably 10 ⁶ Ω or more. According to this, since the eddy current generated by the electromagnetic wave noise entering the metal film 60 hardly flows into the magnetic mold resin 40, it is possible to prevent the deterioration of the magnetic characteristics of the magnetic mold resin 40 due to the inflow of the eddy current. It becomes possible. The resistance value at the interface between the metal film 60 and the magnetic mold resin 40 refers to the surface resistance of the magnetic mold resin 40 when the two are in direct contact with each other. Point to surface resistance. The resistance value at the interface between the metal film 60 and the magnetic molding resin 40 is preferably 10 ⁶ Ω or more over the entire surface, but even if there is a region where the resistance value is partially less than 10 ⁶ Ω I do not care.

The surface resistivity of the magnetic mold resin 40 basically agrees with the volume resistivity of the magnetic mold resin 40. Therefore, when the volume resistivity of the magnetic mold resin 40 is 10 ¹⁰ Ω · cm or more, basically, the surface resistance value of the magnetic mold resin 40 is also 10 ¹⁰ Ω or more. However, as described with reference to FIG. 5, since the magnetic mold resin 40 is diced at the time of manufacture, the magnetic filler 6 may be exposed on the cut surface (that is, the side surface 42). In this case, the volume resistivity The surface resistance value of the side surface 42 may be lower than that in FIG. Similarly, even when the upper surface 41 of the magnetic mold resin 40 is ground for the purpose of reducing the height or roughening, the magnetic filler 6 made of soft magnetic metal may be exposed on the upper surface 41. In this case, the volume The surface resistance of the upper surface 41 may be lower than the resistivity. As a result, even if the volume resistivity of the magnetic mold resin 40 is 10 ¹⁰ Ω · cm or more, the surface resistance value of the magnetic mold resin 40 may be less than 10 ¹⁰ Ω. In such a case, Also, if the surface resistance value of the magnetic mold resin 40 is 10 ⁶ Ω or more, the inflow of the eddy current can be prevented.

When the surface resistance value of the upper surface 41 or the side surface 42 of the magnetic mold resin 40 is reduced to less than 10 ⁶ Ω, a thin insulating material may be formed on the upper surface 41 or the side surface 42 of the magnetic mold resin 40. FIG. 20 is a cross-sectional view showing the configuration of the electronic circuit package 13B according to the first modification, in which the thin insulating film 70 is interposed between the metal film 60 and the top surface 41 and the side surface 42 of the magnetic mold resin 40. Are different from the electronic circuit package 13A shown in FIG. If such an insulating film 70 is interposed, even if the surface resistance value of the upper surface 41 or the side surface 42 of the magnetic mold resin 40 is reduced to less than 10 ⁶ Ω, the metal film 60 and the magnetic mold resin 40 It is possible to make the resistance value at the interface of 10 ⁶ Ω or more, and it is possible to prevent the deterioration of the magnetic characteristics due to the eddy current.

  FIG. 21 is a cross-sectional view showing a configuration of an electronic circuit package 13C according to a second modified example of the present embodiment.

  As shown in FIG. 21, in the electronic circuit package 13C according to the second modification of the present embodiment, the planar size of the magnetic mold resin 40 is slightly smaller than the planar size of the substrate 20, whereby the surface 21 of the substrate 20 is obtained. Is different from the electronic circuit package 13A shown in FIG. 19 in that the outer peripheral portion of the magnetic resin is exposed from the magnetic mold resin 40. Since the other configuration is the same as that of the electronic circuit package 13A shown in FIG. 19, the same elements will be denoted by the same reference numerals and redundant description will be omitted.

  As exemplified by the electronic circuit package 13C according to the present modification, in the present invention, it is not essential that the side surface 42 of the magnetic mold resin 40 and the side surface 27 of the substrate 20 constitute the same plane. It does not matter if it is smaller.

  Further, as shown in an electronic circuit package 13D shown in FIG. 22 which is a third modified example, the metal film 60 may not cover the side surface 27 of the substrate 20. In this case, a power supply pattern 28 G is provided on an outer peripheral portion of the surface 21 of the substrate 20 exposed from the magnetic mold resin 40, and the power supply pattern 28 G is in contact with the metal film 60. As a result, the metal film 60 is given a fixed potential such as a ground potential.

  FIG. 23 is a cross-sectional view showing the configuration of an electronic circuit package 13E according to a fourth modification of the present embodiment.

  As shown in FIG. 23, the electronic circuit package 13E according to the fourth modification of this embodiment has the electrons shown in FIG. 19 in that the planar size of the magnetic mold resin 40 is slightly larger than the planar size of the substrate 20. It differs from the circuit package 13A. Since the other configuration is the same as that of the electronic circuit package 13A shown in FIG. 19, the same elements will be denoted by the same reference numerals and redundant description will be omitted.

  As exemplified in the electronic circuit package 13E according to the present modification, in the present invention, the magnetic mold resin 40 may have a larger plane size than the substrate 20.

  As described above, since the electronic circuit packages 13A to 13E according to the present embodiment use the magnetic mold resin 40 and the surface thereof is covered with the metal film 60, a composite shield structure can be obtained. Thereby, it is possible to effectively shield electromagnetic wave noise emitted from the electronic components 31 and 32 and electromagnetic wave noise incident on the electronic components 31 and 32 from the outside while realizing a reduction in height. In particular, the electronic circuit packages 13A to 13E according to the present embodiment can shield electromagnetic wave noise emitted from the electronic components 31 and 32 more effectively. This is because when the electromagnetic wave noise generated from the electronic components 31 and 32 passes through the magnetic mold resin 40, a part of the electromagnetic wave noise absorbed is absorbed, and a part of the electromagnetic wave noise not absorbed is reflected by the metal film 60 and the magnetic mold resin Because it passes 40 again. As described above, since the magnetic molding resin 40 acts twice on the incident electromagnetic wave noise, the electromagnetic wave noise emitted from the electronic components 31 and 32 can be effectively shielded.

Further, in the electronic circuit packages 13A to 13E according to the present embodiment, when the volume resistivity of the magnetic mold resin 40 is 10 ¹⁰ Ω · cm or more, sufficient insulation required for the mold member can be secured. Moreover, when the resistance value at the interface between the magnetic mold resin 40 and the metal film 60 is 10 ⁶ Ω or more, the eddy current generated by the electromagnetic wave noise incident on the metal film 60 hardly flows into the magnetic mold resin 40. Therefore, it is possible to prevent the deterioration of the magnetic properties of the magnetic mold resin 40 due to the inflow of the eddy current.

  FIG. 24 is a graph showing the noise attenuation amount of the electronic circuit package 13A, and shows a case where the thickness of the substrate 20 is 0.25 mm and the thickness of the magnetic mold resin 40 is 0.50 mm. The metal film 60 is a laminated film of Cu and Ni, and two metal films 60 having different thicknesses of Cu are evaluated. Specifically, the metal film 60 of sample A has a structure in which 4 μm of Cu and 2 μm of Ni are stacked, and the metal film 60 of sample B has a structure in which 7 μm of Cu and 2 μm of Ni are stacked. ing. For comparison, values of samples C and D using a mold material containing no magnetic filler 6 are also shown. The metal film 60 of sample C has a configuration in which 4 μm of Cu and 2 μm of Ni are stacked, and the metal film 60 of sample D has a configuration in which 7 μm of Cu and 2 μm of Ni are stacked.

  As shown in FIG. 24, compared with the case where the molding material containing no magnetic filler 6 is used, the amount of noise attenuation particularly in the frequency band of 100 MHz or less is increased when the composite magnetic sealing material 2 containing the magnetic filler 6 is used. I understand. Further, as for the metal film 60, higher noise attenuation characteristics can be obtained as the thickness is larger.

  25 to 27 are graphs showing the relationship between the film thickness of the metal film 60 included in the electronic circuit package 13A and the noise attenuation amount. FIG. 25 shows noise attenuation at 20 MHz, FIG. 26 at 50 MHz, and FIG. 27 at 100 MHz. For comparison, values when using a mold material not containing the magnetic filler 6 are also shown.

  As shown in FIG. 25 to FIG. 27, it can be seen that the higher the thickness of the metal film 60 is, the higher the noise attenuation characteristic can be obtained in any frequency band. In addition, it is understood that high noise attenuation characteristics can be obtained by using the composite magnetic sealing material 2 including the magnetic filler 6 as compared to the case where the mold material including no magnetic filler 6 is used in any frequency band. .

FIG. 28 is a graph showing the amount of warpage of the substrate 20 at the time of temperature rise and fall of the electronic circuit package 11A (without metal film) and the electronic circuit package 13A (with metal film). For comparison, FIG. 29 shows values when the magnetic filler 6 is replaced with a nonmagnetic filler made of SiO ₂ .

As shown in FIG. 28, it can be seen that the warping of the substrate 20 due to the temperature change is smaller in the electronic circuit package 13A having the metal film 60 than in the electronic circuit package 11A having no metal film 60. Further, as apparent from comparison between FIG. 28 and FIG. 29, the warping characteristics of the electronic circuit packages 11A and 13A using the composite magnetic sealing material 2 including the magnetic filler 6 are the mold including the nonmagnetic filler made of SiO ₂ It is almost equivalent to the case of using the material.

Fourth Embodiment
FIG. 30 is a cross-sectional view showing the configuration of the electronic circuit package 14A according to the fourth embodiment of the present invention.

  As shown in FIG. 30, the electronic circuit package 14A according to the present embodiment is the same as the electronic circuit package 13A according to the third embodiment shown in FIG. 19 except that the shapes of the substrate 20 and the metal film 60 are different. is there. For this reason, the same symbols are given to the same elements, and duplicate explanations are omitted.

  In the present embodiment, the side surface 27 of the substrate 20 is stepped. Specifically, it has a shape in which the side lower portion 27b protrudes more than the side upper portion 27a. The metal film 60 is not formed on the entire side surface of the substrate 20, but is provided so as to cover the side upper portion 27a and the step portion 27c, and the side lower portion 27b is not covered by the metal film 60. Also in the present embodiment, since the power supply pattern 25G is exposed at the side surface upper portion 27a of the substrate 20, the metal film 60 is connected to the power supply pattern 25G through this portion.

  31 and 32 are process diagrams for explaining the method of manufacturing the electronic circuit package 14A.

  First, after the magnetic mold resin 40 is formed on the surface 21 of the collective substrate 20A by the method described with reference to FIGS. 3 and 4, as shown in FIG. 31, the groove 43 is formed along the broken line a indicating the dicing position. Form. In this embodiment, since the power supply pattern 25G crosses the broken line a which is the dicing position, the power supply pattern 25G is exposed from the side surface 27 of the substrate 20 when the collective substrate 20A is cut along the broken line a. The groove 43 completely cuts the magnetic mold resin 40 and does not cut the collective substrate 20A completely. As a result, the side surface 42 of the magnetic mold resin 40 and the upper side surface 27 a and the step portion 27 c of the substrate 20 are exposed inside the groove 43. Here, the depth of the side upper portion 27a needs to be set to a depth at which at least the power supply pattern 25G is exposed.

  Next, as shown in FIG. 32, a metal film 60 is formed by sputtering, evaporation, electroless plating, electrolytic plating, or the like. Thereby, the upper surface 41 of the magnetic mold resin 40 and the inside of the groove 43 are covered with the metal film 60. At this time, the power supply pattern 25G exposed to the side surface upper portion 27a of the substrate 20 is connected to the metal film 60.

  Then, the substrate 20 is singulated by cutting the collective substrate 20A along the broken line a, whereby the electronic circuit package 14A according to the present embodiment is completed.

  As described above, according to the method of manufacturing the electronic circuit package 14A according to the present embodiment, since the groove 43 is formed, the metal film 60 can be formed before the collective substrate 20A is singulated. The formation of the membrane 60 is easy and reliable.

  Although the preferred embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the present invention. It is needless to say that they are included in the scope.

<Creating a composite magnetic sealing material>
830S (bisphenol A type epoxy resin) made by DIC as a main agent, 0.5 equivalent of Dicy DD (dizian diamide) made by Nippon Carbide Industries Co., Ltd. as a curing agent, 0.5 wt% to the main agent, 1 wt% of Shikoku Kasei Kogyo as a curing agent A resin material was prepared by using C11 Z-CN (imidazole) manufactured by corporation.

  A magnetic filler having the composition shown in FIG. 33 was added to the above resin material at 50% by volume, 60% by volume or 70% by volume, and thoroughly kneaded to obtain a paste. In addition, when it was not possible to paste, butyl carbitol acetate was added timely. The paste was applied to a thickness of about 300 μm and thermally cured in the following order: 100 ° C. for 1 hour, 130 ° C. for 1 hour, 150 ° C. for 1 hour, and 180 ° C. for 1 hour. Composition 1 (comparative example) is a magnetic material generally called PB permalloy.

<Measurement of thermal expansion coefficient>
The above-mentioned cured product sheet is cut into a length of 12 mm and a width of 5 mm, and the temperature is raised from room temperature to 200 ° C. at 5 ° C./min using TMA, and expansion at a temperature range of 50 ° C. to 100 ° C. lower than the glass transition temperature The thermal expansion coefficient was calculated from the amount. The results of the measurement are shown in FIG. FIG. 34 also shows the result in the case of using a nonmagnetic filler made of SiO ₂ instead of the magnetic filler.

As shown in FIG. 34, when the magnetic fillers of composition 2 and composition 3 were used, the thermal expansion coefficient was significantly smaller than when the magnetic filler of composition 1 (comparative example) was used. In particular, when the addition amount is 60% by volume or more, the thermal expansion coefficient equivalent to the case of using the nonmagnetic filler made of SiO ₂ is obtained, and when the addition amount is 70% by volume, the thermal expansion The coefficient was 10 ppm / ° C. or less.

<Measurement of permeability>
The above-mentioned cured product sheet was cut into a ring shape having an outer diameter of 7.9 mm and an inner diameter of 3.1 mm, and an effective permeability (μ ′) of 10 MHz was measured using a material analyzer function of Impedance Analyzer E4991 manufactured by Agilent. The results of the measurement are shown in FIG.

  As shown in FIG. 35, the magnetic permeability obtained when the magnetic filler of composition 2 and composition 3 was used was almost equivalent to the magnetic permeability obtained when the magnetic filler of composition 1 (comparative example) was used .

<Discussion>
A composite magnetic sealing material formed by adding magnetic fillers of composition 2 and composition 3 to a resin material provides a thermal expansion coefficient equivalent to that obtained when using a nonmagnetic filler made of SiO ₂ , and a magnetic material made of PB permalloy The same permeability as in the case of using the filler could be obtained. Therefore, if a composite magnetic sealing material formed by adding a magnetic filler of composition 2 or 3 to a resin material is used as a sealing material for an electronic circuit package, warpage of the substrate, peeling of the interface of the molding material, molding material It is possible to obtain high magnetic shield characteristics while preventing cracks and the like.

DESCRIPTION OF SYMBOLS 2 Composite magnetic sealing material 4 Resin material 6 Magnetic filler 7 Insulating coat 8 Nonmagnetic filler 11A, 11B, 12A, 13A to 13E, 14A Electronic circuit package 20 Substrate 20A Assembly substrate 21 Front surface 22 Substrate back surface 23 Land pattern 24 Solder 25 Internal wiring 25G Power supply pattern 26 External terminal 27 Substrate side 27a Substrate side upper part 27b Substrate side lower part 27c Substrate stepped part 28G Power supply pattern 31, 32 Electronic parts 40 Magnetic mold resin 41 Magnetic mold resin upper surface 42 Magnetic mold Resin side 43 Groove 50 Nonmagnetic member 60 Metal film 70 Insulating film 80 Mold 81 Flow path

Claims (21)

A substrate,
An electronic component mounted on the surface of the substrate;
And a magnetic mold resin covering the surface of the substrate so as to embed the electronic component.
The magnetic mold resin is
Resin material,
And a filler mixed in the resin material and having a blending ratio of 30 to 85% by volume,
The filler, the Fe, the metal material mainly composed of Ni includes a magnetic filler containing 32-39 wt%, thereby Ri der thermal expansion coefficient of the magnetic molding resin 15 ppm / ° C. or less,
The surface of the magnetic filler is insulating coated,
The film thickness of the insulating coat Ru der than 20 nm, the electronic circuit package.   The electronic circuit package of claim 1, wherein the metal material further comprises 0.1 to 8 wt% of Co based on the total of the magnetic filler.   The electronic circuit package of claim 1, wherein the filler further comprises a nonmagnetic filler.   The electronic circuit package according to claim 3, wherein an amount of the nonmagnetic filler with respect to a total of the magnetic filler and the nonmagnetic filler is 1 to 40% by volume. The nonmagnetic filler is at least one selected from the group consisting of SiO ₂ , ZrW ₂ O ₈ , (ZrO) ₂ P ₂ O ₇ , KZr ₂ (PO ₄ ) ₃ and Zr ₂ (WO ₄ ) (PO ₄ ) ₂ 5. The electronic circuit package of claim 4 comprising one material.   The electronic circuit package according to claim 1, wherein the shape of the magnetic filler is substantially spherical. The electronic circuit package according to claim 1 , wherein a film thickness of the insulating coat is 30 nm or more.   The electronic circuit package according to claim 1, wherein the resin material is a thermosetting resin material. The electronic circuit package according to claim 8 , wherein the thermosetting resin material includes at least one material selected from the group consisting of an epoxy resin, a phenol resin, a urethane resin, a silicone resin, and an imide resin. The electronic circuit package according to claim 1 , wherein a volume resistivity of the magnetic mold resin is 10 ¹⁰ Ω · cm or more.   The electronic circuit package according to claim 1, further comprising a nonmagnetic member provided between the electronic component and the magnetic mold resin.   The electronic circuit package according to claim 1, further comprising: a metal film connected to a power supply pattern provided on the substrate and covering the magnetic mold resin. The electronic circuit package according to claim 12 , wherein the metal film contains, as a main component, at least one metal selected from the group consisting of Au, Ag, Cu and Al. The electronic circuit package according to claim 12 , wherein a surface of the metal film is covered with an antioxidant coating. The electronic circuit package according to claim 12 , wherein the power supply pattern is exposed on a side surface of the substrate, and the metal film is in contact with the power supply pattern exposed on the side surface of the substrate. A substrate,
An electronic component mounted on the surface of the substrate;
And a magnetic mold resin covering the surface of the substrate so as to embed the electronic component.
The magnetic mold resin is
Resin material,
And a filler mixed in the resin material and having a blending ratio of 30 to 85% by volume,
The filler, the Fe, the metal material mainly composed of Ni includes a magnetic filler containing 32-39 wt%, thereby Ri der thermal expansion coefficient of the magnetic molding resin 15 ppm / ° C. or less,
The surface of the magnetic filler is insulating coated,
The thickness of the insulating coat is 10 nm or more.
The volume resistivity of the magnetic molding resin Ru der ¹⁰ 10 Ω · cm or more, electronic circuit package. A substrate,
An electronic component mounted on the surface of the substrate;
And a magnetic mold resin covering the surface of the substrate so as to embed the electronic component.
The magnetic mold resin is
Resin material,
A magnetic filler containing 32 to 39% by weight of a metal material containing Ni as a main component in Fe, which is blended in the resin material;
And a nonmagnetic filler blended in the resin material,
The compounding amount of the magnetic filler is 30 to 85% by volume of the whole,
The total amount of the non-magnetic filler and said magnetic filler, Ri 50-85 vol% der of the total,
Wherein the surface of the magnetic filler that is covered with a thickness of 20nm or more insulating coating, an electronic circuit package. The electronic circuit package of claim 17 , wherein the metal material further comprises 0.1 to 8 wt% of Co based on the total of the magnetic filler. The electronic circuit package according to claim 17 , wherein a film thickness of the insulating coat is 30 nm or more. The electronic circuit package according to claim 17 , having a volume resistivity of 10 ¹⁰ Ω · cm or more. A substrate,
An electronic component mounted on the surface of the substrate;
And a magnetic mold resin covering the surface of the substrate so as to embed the electronic component.
The magnetic mold resin is
Resin material,
A magnetic filler containing 32 to 39% by weight of a metal material containing Ni as a main component in Fe, which is blended in the resin material;
And a nonmagnetic filler blended in the resin material,
The compounding amount of the magnetic filler is 30 to 85% by volume of the whole,
The total amount of the non-magnetic filler and said magnetic filler, Ri 50-85 vol% der of the total,
The surface of the magnetic filler is covered with an insulating coating having a thickness of 10 nm or more,
Der Ru, electronic circuit package or a volume resistivity of ^{10 10 Ω} · cm.