Classifications

• • H—ELECTRICITY
  • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
  • H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
  • H05K9/00—Screening of apparatus or components against electric or magnetic fields
  • H05K9/0073—Shielding materials
  • H05K9/0081—Electromagnetic shielding materials, e.g. EMI, RFI shielding
  • H05K9/0083—Electromagnetic shielding materials, e.g. EMI, RFI shielding comprising electro-conductive non-fibrous particles embedded in an electrically insulating supporting structure, e.g. powder, flakes, whiskers
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
  • H01F1/00—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties
  • H01F1/01—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials
  • H01F1/03—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity
  • H01F1/12—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of soft-magnetic materials
  • H01F1/14—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of soft-magnetic materials metals or alloys
  • H01F1/20—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of soft-magnetic materials metals or alloys in the form of particles, e.g. powder
  • H01F1/22—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of soft-magnetic materials metals or alloys in the form of particles, e.g. powder pressed, sintered, or bound together
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
  • H01F1/00—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties
  • H01F1/01—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials
  • H01F1/03—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity
  • H01F1/12—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of soft-magnetic materials
  • H01F1/14—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of soft-magnetic materials metals or alloys
  • H01F1/20—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of soft-magnetic materials metals or alloys in the form of particles, e.g. powder
  • H01F1/22—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of soft-magnetic materials metals or alloys in the form of particles, e.g. powder pressed, sintered, or bound together
  • H01F1/24—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of soft-magnetic materials metals or alloys in the form of particles, e.g. powder pressed, sintered, or bound together the particles being insulated
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
  • H01F1/00—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties
  • H01F1/01—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials
  • H01F1/03—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity
  • H01F1/12—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of soft-magnetic materials
  • H01F1/14—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of soft-magnetic materials metals or alloys
  • H01F1/20—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of soft-magnetic materials metals or alloys in the form of particles, e.g. powder
  • H01F1/22—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of soft-magnetic materials metals or alloys in the form of particles, e.g. powder pressed, sintered, or bound together
  • H01F1/24—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of soft-magnetic materials metals or alloys in the form of particles, e.g. powder pressed, sintered, or bound together the particles being insulated
  • H01F1/26—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of soft-magnetic materials metals or alloys in the form of particles, e.g. powder pressed, sintered, or bound together the particles being insulated by macromolecular organic substances
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
  • H01F1/00—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties
  • H01F1/01—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials
  • H01F1/03—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity
  • H01F1/12—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of soft-magnetic materials
  • H01F1/34—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of soft-magnetic materials non-metallic substances, e.g. ferrites
  • H01F1/36—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of soft-magnetic materials non-metallic substances, e.g. ferrites in the form of particles
  • H01F1/37—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of soft-magnetic materials non-metallic substances, e.g. ferrites in the form of particles in a bonding agent
• • H—ELECTRICITY
  • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
  • H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
  • H05K1/00—Printed circuits
  • H05K1/02—Details
  • H05K1/0213—Electrical arrangements not otherwise provided for
  • H05K1/0216—Reduction of cross-talk, noise or electromagnetic interference
  • H05K1/023—Reduction of cross-talk, noise or electromagnetic interference using auxiliary mounted passive components or auxiliary substances
  • H05K1/0233—Filters, inductors or a magnetic substance
• • H—ELECTRICITY
  • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
  • H10W—GENERIC PACKAGES, INTERCONNECTIONS, CONNECTORS OR OTHER CONSTRUCTIONAL DETAILS OF DEVICES COVERED BY CLASS H10
  • H10W42/00—Arrangements for protection of devices
  • H10W42/20—Arrangements for protection of devices protecting against electromagnetic or particle radiation, e.g. light, X-rays, gamma-rays or electrons
• • H—ELECTRICITY
  • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
  • H10W—GENERIC PACKAGES, INTERCONNECTIONS, CONNECTORS OR OTHER CONSTRUCTIONAL DETAILS OF DEVICES COVERED BY CLASS H10
  • H10W42/00—Arrangements for protection of devices
  • H10W42/20—Arrangements for protection of devices protecting against electromagnetic or particle radiation, e.g. light, X-rays, gamma-rays or electrons
  • H10W42/281—Arrangements for protection of devices protecting against electromagnetic or particle radiation, e.g. light, X-rays, gamma-rays or electrons characterised by their materials
  • H10W42/287—Arrangements for protection of devices protecting against electromagnetic or particle radiation, e.g. light, X-rays, gamma-rays or electrons characterised by their materials materials for magnetic shielding, e.g. ferromagnetic materials
• • H—ELECTRICITY
  • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
  • H10W—GENERIC PACKAGES, INTERCONNECTIONS, CONNECTORS OR OTHER CONSTRUCTIONAL DETAILS OF DEVICES COVERED BY CLASS H10
  • H10W44/00—Electrical arrangements for controlling or matching impedance
  • H10W44/20—Electrical arrangements for controlling or matching impedance at high-frequency [HF] or radio frequency [RF]
• • H—ELECTRICITY
  • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
  • H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
  • H05K1/00—Printed circuits
  • H05K1/02—Details
  • H05K1/03—Use of materials for the substrate
  • H05K1/0313—Organic insulating material
  • H05K1/0353—Organic insulating material consisting of two or more materials, e.g. two or more polymers, polymer + filler, + reinforcement
  • H05K1/0373—Organic insulating material consisting of two or more materials, e.g. two or more polymers, polymer + filler, + reinforcement containing additives, e.g. fillers
• • H—ELECTRICITY
  • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
  • H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
  • H05K2201/00—Indexing scheme relating to printed circuits covered by H05K1/00
  • H05K2201/08—Magnetic details
  • H05K2201/083—Magnetic materials
  • H05K2201/086—Magnetic materials for inductive purposes, e.g. printed inductor with ferrite core
• • H—ELECTRICITY
  • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
  • H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
  • H05K2201/00—Indexing scheme relating to printed circuits covered by H05K1/00
  • H05K2201/10—Details of components or other objects attached to or integrated in a printed circuit board
  • H05K2201/10613—Details of electrical connections of non-printed components, e.g. special leads
  • H05K2201/10621—Components characterised by their electrical contacts
  • H05K2201/10689—Leaded Integrated Circuit [IC] package, e.g. dual-in-line [DIL]

Definitions

• the present invention relates to a composite magnetic material obtained by kneading and dispersing a magnetic powder in an organic binder, and more particularly, to a complex magnetic permeability characteristic effective for suppressing electromagnetic interference which is a problem in a high-frequency electronic circuit Z device.
• the present invention relates to an excellent composite magnetic material and a method for producing the same.
• the present invention further relates to, for example, a printed wiring board using the composite magnetic body, and an electromagnetic interference suppressor and an electronic component that can be used for an electronic device. J53 ⁇ 4 technology
• Digital electronic devices that have become increasingly popular in recent years include random access memory (RAM), read-only memory (ROM), microprocessor (MPU), central processing unit (CPU), and image processor arithmetic and logic unit (IPALU).
• RAM random access memory
• ROM read-only memory
• MPU microprocessor
• CPU central processing unit
• IPALU image processor arithmetic and logic unit
• Logic circuits and logic elements are composed of LSIs and ICs composed of a large number of active semiconductor elements, and are mounted on a printed wiring board. In these logic circuits and logic elements, the operation speed is increased and the signal processing speed is increased. In such a logic circuit and the like, a signal that changes at a high speed involves a rapid change in voltage and current, so that the active element generates inductive noise and also causes high-frequency noise.
• radiated electromagnetic interference can be affected by connecting a filter to a circuit that generates inductive noise in electronic equipment, or by causing a problematic circuit (a circuit that generates inductive noise).
• Countermeasures such as keeping away from the circuit, shielding, and grounding are generally adopted.
• the filter power used is expensive, the space for mounting the filter is often limited, the mounting work of the filter is difficult, the use of a filter, etc. Therefore, there is a disadvantage that the number of steps required for assembling the electronic device increases and the cost increases.
• the conductor shield is a measure against electromagnetic interference that utilizes the reflection of electromagnetic waves due to impedance mismatch with the space.
• electromagnetic coupling due to reflection from unwanted radiation sources is promoted, and as a result, secondary electromagnetic interference may occur in some cases.
• Still another object of the present invention is to provide the composite magnetic material. Still another object of the present invention is to provide the electromagnetic interference suppressor.
• Another object of the present invention is to provide an electronic device that is small and lightweight, and that can efficiently suppress electromagnetic interference by having the composite magnetic material.
• Still another object of the present invention is to provide a printed wiring board having a sufficient shielding effect against electromagnetic wave transmission without reducing the shielding effect of the electromagnetically shielded printed circuit board.
• An object of the present invention is to provide a printed circuit board which does not promote electromagnetic coupling at least by reflection. Disclosure of the invention
• the electrically non-conductive substantially consisting of a soft magnetic material powder and an organic binder is provided by at least two anisotropic magnetic fields (H k).
• an electromagnetic interference suppressor substantially composed of a composite magnetic material, wherein the composite magnetic material has electrical non-conductivity, And an organic binder.
• the electromagnetic interference suppressor further comprises: at least two magnetic resonances out of a plurality of magnetic resonances appearing in a microwave frequency region generated by at least two anisotropic magnetic fields (H k). Wherein the anisotropic magnetic fields have different magnitudes from each other.
• At least two kinds of ⁇ -magnetic powder having magnetic anisotropy having different sizes from each other and an organic binder are mixed and molded to form an electrically non-conductive material.
• a method for producing a composite magnetic body, which has good conductivity and has at least two magnetic resonances caused by anisotropic magnetic fields (H k) having different magnitudes from each other, is obtained.
• a printed substrate has a conductor on one side or both sides thereof, and further includes a conductive support, and a composite magnetic material layer provided on both sides of the conductive support.
• the composite magnetic material layer has an insulating property, wherein the composite magnetic material layer is substantially electrically non-conductive from a magnetic powder and an organic binder.
• an electronic device having a printed circuit board and an active element mounted on the printed wiring board, wherein the active element generates radiation-induced noise.
• An electronic device having at least two magnetic resonances caused by two anisotropic magnetic fields (H k), wherein the anisotropic magnetic fields (H k) have different magnitudes from each other is obtained.
• FIG. 1 is a partial cross-sectional view of a conventional printed wiring board
• FIG. 2 is a partial sectional view showing an example of a conventional electronic device
• FIG. 3 is a partial plan view showing another example of the conventional electronic device
• FIG. 4 is a partial sectional view showing another example of the conventional electronic device
• FIG. 5 is a schematic diagram of an evaluation system used for evaluating the characteristics of the electromagnetic interference suppressor according to the present invention
• FIG. 6 is a graph showing a ⁇ -f characteristic curve of the composite magnetic material of Evaluation Sample 1 according to the present invention
• FIG. 7 is a graph showing the ⁇ -f characteristic curve of the composite magnetic material of the evaluation sample 2 according to the present invention.
• FIG. 8 is a graph showing the ⁇ -f characteristic curve of the composite magnetic material of the conventional comparative sample; Dora showing the nf characteristic curve of the composite magnetic material of evaluation sample 3 according to the present invention
• FIG. 10 is a partial cross-sectional view showing a printed wiring board according to a first example to which the present invention is applied.
• FIG. 11 is a second sectional view showing a second example to which the present invention is applied.
• FIG. 12 is a partial cross-sectional view showing a printed wiring board according to an example.
• FIG. 12 is a partial cross-sectional view showing a printed circuit board according to a third example to which the present invention is applied.
• FIG. 13 is a part of an electronic device according to a fourth example to which the present invention is applied. Sectional view
• FIG. 14 is a partial plan view of an electronic device according to a fifth example to which the present invention is applied.
• FIG. 15 is a partial cross-sectional view of the composite magnetic material layer shown in FIGS. 13 and 14.
• FIG. 16 is a partial sectional view of an electronic device according to a sixth example to which the present invention is applied; and FIG. 17 is a partial sectional view of the composite magnetic material layer of FIG. BEST MODE FOR CARRYING OUT THE INVENTION
• printed wiring board 21 has circuit conductors 23 and 25 formed on both sides.
• the circuit conductor has a c-through hole 29 formed by printing or etching for connection between the upper surface and the lower surface.
• electronic device 31 has LSI 33 mounted on one surface of substrate 21.
• 5 13 3 has an LSI main body 35 and a contact bin terminal 37.
• the contact bin terminal 37 extends to the conductor pattern 23 formed on the surface of the substrate 21.
• the LSI body 35 is arranged in a floating state with a space between the surface of the board 21 and the LSI body 35.
• the wiring conductor (pattern) 25 is wired so as to be below the LSI 33 of the wiring board 21.
• FIG. 3 another example of an electronic device is mounted on a wiring board 21 with LSI 39 and 41 similarly to the one described in FIG. These LSI 39 and 41 are wiring conductors (patterns) 43, formed on the wiring board 21.
• the electronic device includes a substrate 21 on which electronic components 49, which are active elements that emit inductive noise, are mounted, and a container that wraps and stores the entire wiring substrate 21.
• Case 51 is included.
• the case 51 includes a resin outer shell 53 and a conductive layer formed by applying a conductive paint to the inside of the outer shell 53.
• the powder characteristics obtained by processing a single raw material species under specific conditions There is a method that utilizes sexual differentiation.
• One particle group exists as primary particles in the same matrix. Another group of particles are aggregated and have insufficient wetting inside, so that the particles are very close to or in contact with each other.
• the effective anisotropic magnetic field is an algebraic sum of the demagnetizing field depending on the sample shape, so that the orientation control of the raw magnetic powder can be positively used.
• any of these methods may be used. It is important to provide a plurality of anisotropic magnetic fields so as to obtain a desired magnetic loss band.
• the dispersion of the imaginary part magnetic permeability occurs with the decrease of the real part magnetic permeability. It is necessary to set a value that gives magnetic resonance to a frequency range lower than the lower limit of the electromagnetic interference suppression frequency band.
• a metal ferromagnetic material such as an iron aluminum silicon alloy (Sendust), an iron nickel alloy (Permalloy), or an amorphous alloy having a high high-frequency magnetic permeability is used.
• Typical examples include powders obtained by pulverization, stretching to tearing, or atomization granulation.
• the non-conductivity of the composite magnetic material which is a necessary element of the present invention, is as follows. It is desirable that at least the surface be oxidized so that the particles can be isolated, thereby electrically isolating the individual particles.
• diamagnetic powder of the present invention powder of an oxide soft magnetic material such as spinel type ferrite or planar type ferrite can be used, and mixed use with the metal soft magnetic powder is also possible.
• oxide soft magnetic material such as spinel type ferrite or planar type ferrite
• the organic binder used as an auxiliary material of the present invention includes polyester resin, polyethylene resin, polyvinyl chloride resin, polyvinyl butyral resin, polybutyral resin, Thermoplastic resins such as urethane resin, cellulose resin, ABS resin, nitrile-butadiene rubber, styrene-butadiene rubber, or copolymers thereof, epoxy resins, phenol resins, amide resins, and imid resins Thermosetting resins such as resins can be used.
• Thermoplastic resins such as urethane resin, cellulose resin, ABS resin, nitrile-butadiene rubber, styrene-butadiene rubber, or copolymers thereof, epoxy resins, phenol resins, amide resins, and imid resins
• Thermosetting resins such as resins can be used.
• the means for obtaining the composite magnetic material by kneading and dispersing the constituent elements of the present invention described above is not particularly limited, and a preferred method may be selected based on the properties of the binder used and the ease of the process.
• the composite magnetic body and the electromagnetic interference suppressor of the present invention have a plurality of anisotropic magnetic fields (Hk) having different magnitudes from each other, and accordingly, a plurality of magnetic resonances appear in different frequency regions. Therefore, the imaginary part magnetic permeability // "appearing in different frequency regions due to the plurality of magnetic resonances is superimposed, and as a result, a broadband / ⁇ dispersion characteristic can be obtained. // * is a magnetic loss term necessary for absorption of electromagnetic waves, and when the value of ⁇ "is large and extends over a wide band, an excellent electromagnetic interference suppression effect appears.
• the ferromagnetic powder used in the present invention is at least oxidized in its surface force, even when the filling rate of the powder is high, the individual magnetic particles are present in an electrically isolated state. As a result, not only is the frequency characteristic degrading due to eddy current loss as seen in a bulk material with good conductivity, but also the reflection of electromagnetic waves on the surface due to impedance mismatch with space is less likely to occur. An excellent electromagnetic interference suppression effect can be exhibited in the high frequency range.
• a plurality of iron-aluminum-silicon alloy powders with different average particle size forces prepared by the water atomizing method are prepared, stretched and pulverized under various conditions using an attritor and a pin mill, and further processed in a hydrocarbon organic solvent.
• the mixture was stirred for 8 hours while introducing a gas mixture of nitrogen and oxygen with an oxygen partial pressure of 35%, and subjected to liquid phase slow acid treatment, followed by classification to obtain a plurality of powder samples with different anisotropic magnetic fields (Hk). .
• Hk anisotropic magnetic fields
• the stretched and pulverized iron-aluminum-silicon alloy powder was dried under reduced pressure, and the sample was subjected to gas-phase deoxidation in a nitrogen-oxygen mixed gas at an oxygen partial pressure of 20%. 10 and Si 10 bonds were detected, and it was confirmed that at least the surface-oxidized soft magnetic powder that can be used in the present invention can be produced by a liquid phase or gas phase deoxidation method. .
• a soft magnetic material paste having the composition shown in Table 1 below was prepared, formed into a film by the doctor blade method, subjected to hot pressing, and then cured at 85 ° C for 24 hours for evaluation. Sample 1 was obtained.
• the easy axis of magnetization and the direction of particle orientation were in the in-plane direction of the sample film.
• the composite magnetic material processed into a toroidal shape was used for the measurement of the f characteristics. This is inserted into the test fixture that forms a one-turn coil, and And / ⁇ was obtained by measuring the impedance.
• the electromagnetic interference suppression effect was verified by the evaluation system shown in Fig. 5, and the sample of the electromagnetic interference suppression body 61 had a copper plate 63 force ⁇ A 2 O cm composite magnetic material 65 was used.
• micro-loop antennas 69 and 71 for transmitting and receiving electromagnetic fields with a loop diameter of 1.5 mm were used for the source and receiving elements using the electromagnetic wave source oscillator 67.
• a network analyzer (electromagnetic boat measuring instrument) 73 was used to measure the coupling level.
• a magnetic paste having the composition shown in Table 2 below was prepared, and a sample 2 for evaluation was obtained in the same manner as for sample 1.
• a magnetic paste having the composition shown in Table 3 below was prepared, and a comparative sample was obtained in the same manner as in Sample 1.
• the obtained comparative sample was analyzed using a vibrating magnetometer and a scanning electron microscope.
• the place, c Table 3 were almost isotropic in magnetic
• the f-characteristic shows the “ ⁇ -like tendency” observed in the composite magnetic material, and the distribution of ⁇ is not wide. That is, from these results, it can be seen that the composite magnetic materials of Sample 1 and Sample 2 of the present invention have a wide-band magnetic loss characteristic in a high frequency range.
• the powder filling rate, surface resistance, ⁇ "distribution, and electromagnetic interference suppression effect of each sample are shown in Table 4.
• the surface resistance is a value measured by the ASTM-D-257 method.
• the value of the suppression effect is the signal attenuation when the copper plate is used as a reference (O dB)
• O dB the signal attenuation when the copper plate is used as a reference
• sample 1 of the present invention the value of surface resistance Samples 2 and the comparative sample both have a 1 0 ' ⁇ 1 0 8 ⁇ , by using the magnetic powder at least the surface is oxidized, the composite magnetic body non Good conductivity can be obtained, and surface reflection of electromagnetic waves due to impedance mismatch such as that observed in conductors and bulk metallic magnetic materials can be suppressed.
• the powder filling rate is lower than that of the comparative sample. Nevertheless, it shows a good effect of suppressing electromagnetic interference, and it can be understood that the effect of expanding the /// distribution according to the present invention is extremely effective in suppressing electromagnetic interference.
• a magnetic paste having the composition shown in Table 5 below was prepared, and was formed into a film by the doctor blade method.After hot pressing, curing was performed at 85 ° C for 24 hours. Obtained.
• This sample 3 had // f characteristics in the same manner as sample 1.
• Figure 9 shows the results. The obtained sample 3 was analyzed using a scanning electron microscope, and it was found that the particle arrangement direction was the sample film surface direction. Table 5
• the composite magnetic material of the present invention and the electromagnetic interference suppressor using the same have a plurality of anisotropic magnetic fields (Hk) having different magnitudes from each other, and accordingly, have different frequency regions. Since a plurality of magnetic resonances appear, broadband /// ⁇ dispersion characteristics can be obtained.
• the imaginary part permeability ⁇ is a magnetic loss term necessary for absorbing electromagnetic waves, and an excellent electromagnetic interference suppressing effect appears when the value of is large and over a wide band. That is, it is possible to provide a thin electromagnetic interference suppressor that is effective for suppressing electromagnetic wave interference inside high-frequency electronic devices such as mobile communication devices.
• the composite magnetic body of the present invention and the electromagnetic interference suppressor using the same can easily impart flexibility as can be seen from the components thereof, and can cope with complicated shapes and withstand severe vibration resistance. It is possible to respond to impact demand.
• FIG. 10 there is shown an example in which the electromagnetic interference suppressing body using the composite magnetic material of the present invention is applied to a printed wiring board.
• This printed wiring board has circuit patterns 23, 25, and 29 similarly to the conventional printed wiring board shown in FIG. 1, and is omitted in the drawing.
• the printed S3 ⁇ 43 ⁇ 4 board 21 a of the first example has a structure different from the conventional one. That is, the printed wiring board 21 a of the first example has a conductive support or a conductive soft magnetic support 75 having a magnetic property. Further, the printed wiring board 21 a has an insulating ⁇ magnetic layer 77 a provided on both surfaces of the conductive support 75.
• the insulating ⁇ magnetic material layer 77 a contains a ⁇ magnetic powder portion 79 and an organic binder 81.
• the soft magnetic material powder portion 79 has a flat shape and a Z or needle-like particle shape shown in Table 1, and has different anisotropic magnetic fields from each other. Further, the organic binder is contained to form a matrix of the insulating ⁇ magnetic layer 77a.
• a second example of the printed circuit board has a conductive support 75 and insulating magnetic layers 77 b provided on both sides of the conductive support 75.
• the printed wiring board 21 b has a pair of dielectric layers 83 provided on both sides of the insulating diamagnetic layer 77 b. They have a different structure from FIG. Therefore, the printed circuit board according to the second example has a structure in which the insulating soft magnetic layer 771) is interposed between the conductive support 75 and the dielectric layer 83.
• the insulating diamagnetic layer 77b includes a flat, Z- or needle-shaped diamagnetic powder portion made of two kinds of powders having mutually different anisotropic magnetic fields.
• the insulating ⁇ -magnetic material layer 77 b contains an organic binder 81 forming a matrix thereof.
• Dielectric layer 83 contains dielectric powder 85 and organic binder 81.
• the organic binder 81 is included to form a matrix of each dielectric layer 83.
• a third example of the printed S3 ⁇ 43 ⁇ 4 substrate includes a conductive support 765 and insulating ⁇ magnetic material layers 77 c provided on both surfaces of the conductive support 75. have.
• This insulating soft magnetic material layer 77c is different from the first example and the second example in the difference. It has a flat, roughly Z- or acicular granular ⁇ -magnetic powder portion 75 made of two kinds of powders having an anisotropic magnetic field and different anisotropic magnetic fields from each other.
• the insulating soft magnetic layer 77 c includes a dielectric powder 85 and an organic binder 81.
• the conductive handle or the conductive magnetic sculpture 65 may be, for example, a conductive plate, a stitched conductive plate, or a woven fabric of conductive fibers.
• the conductive ⁇ magnetic support 65 may be a ⁇ magnetic metal plate, a stitch-shaped ⁇ magnetic metal plate, or a woven fabric of a ⁇ magnetic metal fiber.
• the conductive ferromagnetic plate 65 may be made of a metal plate such as a copper thin plate, a stainless steel thin plate, or an aluminum thin plate, or a so-called punched metal obtained by finely drilling them, or a fine cut in the thin plate. Later, a so-called expanded metal that has been subjected to a stretching process, a wire mesh obtained by adding a fine wire conductor in a stitch shape, or the like can be used.
• permalloy or iron-silicon steel, etc. in which only the material has soft magnetism in the same form, it can be expected to increase the effect of suppressing electromagnetic interference particularly at relatively low L and frequency, so select according to the application. Desirable power.
• a conductive support 75 (in which a film is formed on one or both sides of an insulating base material such as polyimide base material by a doctor blade method, a gravure coating method, or a reverse coating method without forming a sheet) Or a conductive soft magnetic support).
• a conductive or conductive hard magnetic film formed on one or both surfaces of an insulating substrate such as a polyimide substrate by a vapor deposition method or a plating method can be used as the conductive support 75.
• the dielectric powder 85 that can be used to form the dielectric layer 83 or the insulating soft magnetic layer 77 c has a large dielectric constant in a high-frequency region, and the frequency characteristic of the dielectric constant ⁇ A relatively flat force is preferred.
• Examples include barium titanate-based ceramics, zirconate titanate-based ceramics, lead verovskite-based ceramics, and the like.
• the organic binder 81 used to form the insulating soft magnetic layer 77a, 77b, 77c includes polyester resin, polyvinyl chloride resin, polyvinyl butyral resin, polyurethane resin, and the like.
• thermosetting resins such as cellulose resin, nitrile-butadiene rubber, styrene-butadiene rubber, or their copolymers, thermosetting resins such as epoxy resin, phenol resin, amide resin, and imid resin Resins and the like can be given.
• a paper base material such as linter paper or kraft paper
• a glass base material such as glass cloth, glass mat, glass paper, quartz fiber, or a polyester fiber or an aramide fiber
• a synthetic resin fiber base material such as that described above.
• the printed Ei ⁇ substrate of the present invention can easily be given flexibility as can be seen from the components thereof, and can cope with complicated shapes.
• the printed wiring board of the present invention is provided with a wiring conductor on a printed 1-1 board having a structure in which an insulating and magnetic layer is provided on both surfaces of a conductive support.
• the print and substrate of the present invention have an insulating magnetic layer on both sides of the conductive support, and provide a dielectric layer on at least one surface of the insulating magnetic layer. The conductor strength is provided on the printed circuit board with the above configuration.
• this conductive support forming the printed wiring board the same shielding effect as that of the above-mentioned electromagnetic shielding arrangement! Works on the surface facing the substrate surface serving as a noise source, Electromagnetic interference is suppressed.
• secondary electromagnetic coupling due to unnecessary radiation due to reflections occurring in the same wiring board surface on the noise source side is suppressed by a layer of insulative magnetic powder containing magnetic powder and an organic binder.
• the soft magnetic powder is also flat or acicular in shape, shape anisotropy appears, and in the high frequency region, the complex magnetic permeability based on magnetic resonance increases, and the unnecessary radiation component is reduced in efficiency. Sucking Income is suppressed.
• the layer of the insulating ⁇ magnetic material can be formed into an insulating layer by pulverizing finely using a ⁇ magnetic metal, which is a conductive substance, and kneading and dispersing it with an insulating organic binder.
• a ⁇ magnetic metal which is a conductive substance
• kneading and dispersing it with an insulating organic binder since the dielectric powder is mixed with the insulating soft magnetic material layer to achieve impedance matching with the space, reflection of unnecessary radiation on the surface of the insulating magnetic material hardly occurs.
• an electronic device 87 according to the fourth example differs from the conventional electronic device 31 shown in FIG. 2 in the following points.
• an insulating ⁇ ⁇ magnetic layer 89 is printed on the substrate 25 between the surface of the wiring substrate 21 and the lower surface of the LSI body 35.
• the insulating soft magnetic material layer 89 is located immediately below the LSI main body 35.
• the area of the insulating ⁇ magnetic material layer 89 is the same as the area of LSI 35.
• the insulating soft magnetic layer 89 focuses the magnetic flux generated by the high-frequency electromagnetic field generated by the LSI 35.
• the inductive coupling force between the LSI 43 and the wiring board 1 becomes weak, and noise generated in the wiring board 25 can be efficiently suppressed.
• the electronic device according to the fifth example has substantially the same configuration as the conventional example in FIG. 3, but this electronic device 81 differs from the conventional example in the following points. I have. Between the wiring conductors 43 and 45 and between the wiring conductors 45 and 47, an insulating ⁇ magnetic material layer 89 is printed on the IS ⁇ substrate 21 ⁇ respectively. As described with reference to FIGS. 2 and 3, the insulating soft magnetic layer 89 converges the magnetic flux due to the high-frequency electromagnetic field generated from each of the wiring conductors 43, 45, and 47. As a result, the crosstalk force between the wiring conductors 43, 45, and 47 is suppressed.
• the insulating soft magnetic layer 89 will be described with reference to FIG. O 97/04469 _ ⁇ g g PCT / JP96 / 02040
• the insulating magnetic layer 89 contains a magnetic powder portion 79 and an organic binder 81.
• the ferromagnetic powder 79 is uniformly dispersed in the organic binder 81.
• the shape of the soft magnetic material powder portion 89 is made of two types of powders having mutually different anisotropic magnetic fields, and is flat or needle-like, or flat and needle-like, respectively.
• the ferromagnetic powder 79 the powders shown in Tables 1, 2 and 4 above are used.
• the organic binder 81 include, for example, polyester resin, polyvinyl chloride resin, poly (vinyl butyral) resin, polyurethane resin, cellulose resin, nitrile-butadiene rubber, and styrene-butadiene rubber.
• Thermosetting resins such as plastic resins or copolymers thereof, epoxy resins, phenol resins, amide-based resins, and imid-based resins are used.
• the magnetic paste shown in Table 1 above is printed on the substrate where the active element is mounted and the substrate between the wiring conductors arranged in the if direction. 'Cure.
• an insulating soft magnetic layer 89 having a thickness of 0.3 mm was formed on the wiring board.
• Analysis of the insulating ⁇ -magnetic material layer 89 using a vibrating magnetometer and a scanning electron microscope revealed that the easy axis of magnetization and the orientation direction of the magnetic particles were in the sample plane.
• the circuit was operated. In this state, the electromagnetic field strength under the IS ⁇ substrate was measured with a spectrum analyzer to confirm the effect of electromagnetic interference suppression.
• the electromagnetic interference can be effectively suppressed by providing the insulating soft magnetic material layer on the wiring board at a position where unnecessary radiation is a problem.
• the insulating ⁇ magnetic layer can be made flexible, and as a result, not only can it be deformed into a complicated shape, but also it is good against impact. Can be handled.
• An insulating magnetic layer is formed between the wiring substrate and the active element, and By forming the insulating ⁇ magnetic layer between the patterns on the plate, an increase in electromagnetic coupling due to unnecessary radiation is suppressed by the insulating ⁇ magnetic layer.
• the insulating ⁇ magnetic layer is originally made of a conductive material ⁇ magnetic metal in the form of fine powder, and after being oxidized, dispersed in an organic binder, it becomes electrically nonconductive. ing.
• the shape of the soft magnetic material powder at least one of a flat shape and a needle shape, a shape magnetic anisotropy appears, and a complex magnetic permeability based on magnetic resonance increases in a high frequency region, This makes it possible to efficiently suppress unnecessary radiation components.
• an insulating ⁇ magnetic material is provided between an active element serving as a noise source and a B3 ⁇ 4l substrate, and an insulating ⁇ magnetic material is provided between wiring conductors as necessary.
• the ability to effectively suppress mutual interference due to electromagnetic induction and unnecessary electromagnetic waves is a power function. Further, since no filter or the like is required, there is an effect that a reduction in size and weight can be achieved. As a result, electromagnetic interference in high-frequency devices such as mobile communication devices can be suppressed.
• this electronic device has the same configuration as the electronic device shown in FIG. 4 except that the case structure is different. That is, the case 91 is provided with the electromagnetic interference suppressor 93 inside the outer shell 53. In this electronic device, the electromagnetic interference suppressor 93 has a thickness of 0.5 mm.
• the electromagnetic interference suppressor 93 collects the magnetic flux due to the high-frequency electromagnetic field generated by the electronic component 49, thereby radiating noise to the outside and other components mounted close to the wiring board 21. Inductive coupling to electronic components is weakened to suppress inductive noise, which is unnecessary electromagnetic waves. As a result, in the electronic device, mutual interference between components inside the circuit on the wiring board 21 and electromagnetic induction between the power supply and the signal line are suppressed, and electromagnetic interference such as malfunction is prevented.
• FIG. 17 is a partial cross-sectional view showing the basic configuration of the electromagnetic interference suppressor 93.
• the electromagnetic interference suppressor 93 includes a conductive or insulating support 95 and an insulating ⁇ magnetic material layer 97. Further, the insulating magnetic layer 97 is made of two kinds of powders having different anisotropic magnetic fields for the organic binder 81 and each other dispersed in the organic binder.
• the magnetic powder part consists of 79.
• the ferromagnetic powder 79 is uniformly dispersed in the organic binder 81 as shown.
• the conductive support 95 when the support 95 is made conductive in the electromagnetic interference suppressor 93, the conductive support 95 may be, for example, one of a conductive plate, a stitched conductive plate, and a woven plate of conductive fibers. In this case, it is preferable to use a case 91 made of a nonmetal such as resin and subjected to ⁇ ⁇ .
• the insulating support 95 may be, for example, one of an insulating plate, a stitched insulating plate, and a woven plate of insulating fibers.
• the case 91 made of metal, coated with a conductive paint, or deposited with a conductive film.
• the material of the soft magnetic material powder part 79 those shown in Tables 1, 2, and 4 can be used.
• examples of the material of the organic binder 81 include, for example, polyester resin, polyvinyl chloride resin, polyvinyl butyral resin, polyurethane resin, cellulose resin, nitrile-butadiene rubber, styrene-butadiene rubber, and the like.
• thermosetting resins such as epoxy resins, phenol resins, amide resins, and imido resins are also included.
• the support and the insulating member are provided between the package body on which the active element that emits inductive noise is mounted and the package body that wraps around the package body. Since inductive noise is suppressed by the electromagnetic interference suppressor made of magnetic material, radiated noise radiated from the mounted part to the outside, mutual interference between components inside the circuit on the mounted part (wiring board) In addition, electromagnetic induction between the power supply and the signal line is easily suppressed, and electromagnetic interference such as malfunction is prevented.
• the insulating ferromagnetic material in the electromagnetic interference suppressor is composed of an organic binder and two types of flat or needles having different magnetic anisotropies dispersed in the organic binder. ⁇ magnetic powder in the form or a mixture of them, and the support in the electromagnetic interference suppressor is conductive or insulative. Transmission attenuation without increasing radiation reflection Can be secured large.
• the electromagnetic interference suppressor is a foil plate, the entire device including components for noise suppression can be made smaller and lighter than before, and can be configured at a low price.
• the electromagnetic interference suppressor can be easily given flexibility by its constituent elements, it can be deformed into a complicated shape, and can be used even under severe vibration or impact conditions. The applicability will be extremely excellent. Therefore, even when used under severe environmental conditions typified by mobile communication equipment, this electronic device has extremely high utility value in that it can stably suppress electromagnetic interference. Industrial applicability
• the composite magnetic material according to the present invention is used for an electromagnetic wave interference suppressor and is most suitable for preventing noise of a printed wiring board in an electronic component, an electronic component having an active element mounted on the printed wiring board, and the like. is there.

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• Engineering & Computer Science (AREA)
• Chemical & Material Sciences (AREA)
• Dispersion Chemistry (AREA)
• Power Engineering (AREA)
• Physics & Mathematics (AREA)
• Electromagnetism (AREA)
• Microelectronics & Electronic Packaging (AREA)
• Spectroscopy & Molecular Physics (AREA)
• Shielding Devices Or Components To Electric Or Magnetic Fields (AREA)
• Soft Magnetic Materials (AREA)
• Aerials With Secondary Devices (AREA)

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• 1995
  • 1995-07-20 JP JP7183911A patent/JPH0935927A/ja active Pending
• 1996
  • 1996-07-20 TW TW085108847A patent/TW305048B/zh not_active IP Right Cessation
  • 1996-07-22 DE DE69604771T patent/DE69604771T2/de not_active Expired - Lifetime
  • 1996-07-22 KR KR1019970701959A patent/KR100267358B1/ko not_active Expired - Lifetime
  • 1996-07-22 CN CNB961910607A patent/CN1135574C/zh not_active Expired - Lifetime
  • 1996-07-22 EP EP96924176A patent/EP0785557B1/en not_active Expired - Lifetime
  • 1996-07-22 WO PCT/JP1996/002040 patent/WO1997004469A1/ja not_active Ceased

Patent Citations (4)

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