Sony Corporation

Other

Nitto-Denko Corporation

Toda Kogyo Corporation

Katsumi Okayama

Junichi Toyoda

Yoshihiro Kato

Kaoru Kobayashi

Kazumasa Igarashi

Sakan Iwashita

Koichiro Inomata

Satoshi Sugimoto

Yoshinori Ito

Hiroki Ito

Tetsuya Yamamoto

Tomoya Yamaura

Shinichi Kuroda

Koji Nitta

Makoto Suzuki

Akihisa Hosoe

Shinji Inazawa

Minoru Ikarashi

Makoto Motoyoshi

Yoshiki Kanayama

Tatsushiro Hirata

Akira Iga

Masaki Orihashi

Shigehisa Yamamoto

Takuya Eto

Takashi Miyazaki

Kazushi Nishimoto

An electromagnetism suppressing material has an increased electromagnetism suppressing effect, can be flexibly formed in various shapes, and is inexpensive. An electromagnetism suppressing device uses the electromagnetism suppressing material, and an electronic appliance uses the electromagnetism suppressing material or the electromagnetism suppressing device. The electromagnetism suppressing material is a liquid material and/or gel material with electrical polarity.

Electromagnetism suppressing material, electromagnetism suppressing device, and electronic appliance

A method for producing a magnetic particle forming a magnetic material for absorbing electromagnetic waves comprises the steps of mixing an organometallic complex or a metal salt with a chain polymer and dissolving the mixture in a solvent (step S); raising the temperature of the mixture to reaction temperature (step S), carrying out a reaction at the reaction temperature (step S); and forming the magnetic particle having a structure that the periphery of each fine particle formed from the organometallic complex or the metal salt is surrounded by the chain polymer and recovering the formed magnetic particle after the reaction (step S). The magnetic particle has a nanogranular structure to become a magnetic material for absorbing electromagnetic waves. Such a magnetic particle is produced by a wet reaction. Thus, a larger amount of magnetic particle can be produced by one reaction.

Polymer-coated magnetic particle and magnetic material for absorbing electromagnetic waves

A portable telephone having an antenna for transmitting and/or receiving a wireless signal, a microphone for generating a sound signal corresponding to an input sound, a transmitting and receiving circuit for generating a wireless signal corresponding to the sound signal generated by the microphone to transmit the wireless signal through the antenna and generating a sound signal corresponding to the wireless signal received by the antenna, a receiver for outputting sound corresponding to the sound signal generated by the transmitting and receiving circuit, a shield case for surrounding and housing all or part of the transmitting and receiving circuit and being conductive, an electric wave absorber with one face in contact with a predetermined area of the shield case for absorbing an electric wave, and a conductive layer formed on another face of the electric wave absorber and electrically connected to the shield case.

Communication apparatus and portable telephone

Disclosed is a flat-type antenna apparatus which has a radiating conductor and a reference conductor disposed opposite to each other and performs feeding between the radiating conductor and the reference conductor at a position offset from the center of the radiating conductor center. The antenna includes: an insulative material layer which has relative magnetic permeability greater than 1 and is placed in a gap between the radiating conductor and the reference conductor; and a short-circuiting conductor which is disposed at a position to suppress unintended excitation and enables electric conduction between the radiating conductor and the reference conductor.

Antenna apparatus

It is an object of the invention to relax magnetic saturation and realize a high-performance magnetic shield effect that is suitable for magnetic devices such as an MRAM. A magnetic shield member of the invention is suitable for a magnetic memory device in which a magnetic random access memory (MRAM) consisting of a TMR element formed by stacking a magnetization fixed layer with a direction of magnetization fixed and a magnetic layer, in which a direction of magnetization can be changed, via a tunnel barrier layer is sealed by a sealing material such as resin. A planar shape or a sectional shape of magnetic shield plates provided on the sealing material in order to magnetically shield the MRAM is a shape in which a side substantially perpendicular to a direction of an outer magnetic field and a side substantially parallel to the direction of an outer magnetic field are not orthogonal to each other, in particular, circular, polygonal, or the like, whereby it is possible to relax magnetic saturation of the magnetic shield plate and keep the magnetic shield effect.

Magnetic shield member, magnetic shield structure, and magnetic memory device

A non-volatile magnetic memory device is proposed, which provides sufficient magnetic shielding performance for external magnetic fields. A first magnetic shield layerand a second magnetic shield layer, both made of a soft magnetic metal, are formed respectively on the bottom surface of the transistor section, which is the mounting side of the MRAM device, and on the top surface of the bit line, which is opposite to the bottom surface of the mounting side of the MRAM device. On the second magnetic shield layer, a passivation filmis formed. The magnetic flux penetrated from the external magnetic field, is suppressed below the inversion strength of the MRAM device, thereby improving reliability. Moreover, by using soft magnetic metal as the magnetic shield layers, the magnetic shield layers can be formed by the sputtering technique, particularly composing elements can be partly shared as elements of the targets to be used for forming various layers composing the MRAM deviceby the sputtering technique, thereby enabling to form various layers of the MRAM devicein a single sputtering chamber efficiently.

Magnetic non-volatile memory device

A memory device is proposed which enables to guarantee the operation of MRAM elements being magnetically shielded against a large external magnetic fields without being affected by an internal leakage magnetic field. The MRAM elementswhich are shielded by magnetic shield layersare placed at an intermediate regionavoiding an edge regionand a center regionof the magnetic shield layersso that the MRAM element is secured to operate normally without being affected by the internal leakage magnetic field avoiding the edge regionwhere the magnetic shield effect is reduced by the exterior magnetic field, and avoiding the central regionwhere the internal leakage magnetic field is large.

Detailed description of the presently preferred embodiments

A resin component for encapsulating a semiconductor includes magnetic powder and silica powder whose average particle diameter is smaller than the average particle diameter of the magnetic powder. Thus, the curing body of the resin component for encapsulating a semiconductor has an electromagnetic wave shielding function by the magnetic powder. Since the spaces of the magnetic powder are filled with the silica powder whose average particle diameter is small, the moldability of the curing body is improved and the insulating characteristics thereof are enhanced. Such a resin component for encapsulating a semiconductor is employed, there can be produced a preferably formed and encapsulated semiconductor device having the electromagnetic wave shielding function and having no malfunction generated due to leakage current from a semiconductor element.

Resin component for encapsulating semiconductor and semiconductor device using it

Method for producing magnetic particle, magnetic particle and magnetic material

Epoxy resin composition used for encapsulating semiconductor and semiconductor device using the composition

The portable telephone capable of more effectively reducing the electromagnetic energy to be radiated therefrom and absorbed by the human body during its use is provided. The portable telephone is comprised of: an antenna; a microphone; a transmitting circuit for modulating a first audio signal to produce a first radio signal, and transmitting the same; a receiving circuit for demodulating a second radio signal received via the antenna, and reproducing a second audio signal; a receiver for outputting an audio sound corresponding to the second audio signal; a printed circuit board on which the receiving and the transmitting circuits are mounted; a shield case surrounding the printed circuit board so as to suppress the electromagnetic interference between the printed circuit board and the antenna; the housing for accommodating the shield case and so on; the electromagnetic wave absorption layer including a magnetic loss material, formed at least in a part between the shield case and the housing; and the electromagnetic wave reflection layer including a magnetic reflection material, formed between the housing and the electromagnetic wave absorption layer.

Portable telephone

A magnetic powder is produced by use of a plating mold M which is pattern-formed with an electrode range corresponding to the shape of a magnetic powder and an insulative range surrounding the periphery of the electrode range, precipitating films of the magnetic material selectively in the electrode range through an electroplating and then peeling the films from the plating mold. The flat magnetic powders where are regular in piano shapes and diameters among or between powders or where average crystal grain diameters are 100 nm or smaller, are much dispersed into an insulative resin as a bonding agent.

Electromagnetic wave absorbent and method for producing magnetic powder for the same

An electromagnetic wave suppressor sheet formed into a sheet-like shape out of a material made of synthetic resin in which powder of conjugated magnetic particles surface-treated with an insulating inorganic material has been dispersed.

Electromagnetic wave suppressor sheet

A magnetic material exhibiting a high permeability at a high frequency range is materialized and a radio wave absorber exhibiting an excellent radio wave absorbing property by using such magnetic material is provided. The radio wave absorber comprises a mixed material containing a magnetic material grain, a resin material and a ceramic material or a low-melting-point metal material, in which the magnetic material grain is made into a disc shape is provided.

Radio wave absorber

There is disclosed a thinner-layered radio wave absorber having high absorption performance for a high frequency electromagnetic wave. The radio wave absorber, even when having a magnetic layer of not more than 1 mm in thickness, achieves satisfactory absorption characteristics for the high frequency electromagnetic wave by adopting a structure that a conductor is fixedly attached to a face opposite to an electromagnetic-wave incident face of the magnetic layer of single-layered structure, and also arranging the magnetic layer to have values of a real part &mgr;&prime; and an imaginary part &mgr;&Prime; of complex relative magnetic permeability of the magnetic layer satisfying an expression of &mgr;&Prime;&gE;m&mgr;&prime;&minus;n (m: real number of m>0, n: real number of n&gE;0) outside an impedance mismatching region.

Growing community of inventors

Kanagawa, Japan

Katsumi Okayama