Nec Tokin Corporation

Tokin Corporation

Yoshio Awakura

Hiroshi Ono

Shinya Watanabe

Satoshi Shiratori

Shigeyoshi Yoshida

Koji Kamei

Yutaka Shimada

Masahiro Yamaguchi

Michio Nemoto

Mikio Nishimura

Eiji Yamanaka

In a semiconductor bare chip () on the front surface whereof is formed an integrated circuit, a magnetic loss filmis formed on the back surface of that semiconductor bare chip.

Electromagnetic noise suppressor, semiconductor device using the same, and method of manufacturing the same

In order to provide a wiring board comprising a magnetic material effective in suppressing spurious radiation in semiconductor devices and electronic circuits and the like that operate at high speeds, a wiring board () comprises an insulative base material (), conductor patterns (to) formed thereon, and magnetic thin films (to) formed on the conductor patterns (to). The magnetic thin film is configured of a magnetic loss material represented by M-X&#x2014;Y, where M is at least one of Fe, Co, and Ni, X is at least one element other than M or Y, and Y is at least one of F, N, and O, the maximum value &#x3bc;&#x2033;max of the loss factor &#x3bc;&#x2033; that is an imaginary component in the complex permeability characteristic of the magnetic loss material exists within a frequency range of 100 MHz to 10 GHz, and a relative bandwidth bwr is not greater than 200% or not smaller than 150% where the relative bandwidth bwr is obtained by extracting a frequency bandwidth between two frequencies at which the value of &#x3bc;&#x2033; is 50% of the maximum &#x3bc;&#x2033;and normalizing the frequency bandwidth at the center frequency thereof.

Wiring board comprising granular magnetic film

In order to provide a wiring board comprising a magnetic material effective in suppressing spurious radiation in semiconductor devices and electronic circuits and the like that operate at high speeds, a wiring board () comprises an insulative base material (), conductor patterns (to) formed thereon, and magnetic thin films (to) formed on the conductor patterns (to. The magnetic thin film is configured of a magnetic loss material represented by M&#x2014;X&#x2014;Y, where M is at least one of Fe, Co, and Ni, X is at least one element other than M or Y, and Y is at least one of F, N, and O, the maximum value &#x3bc;&#x2033;max of the loss factor &#x3bc;&#x2033; that is an imaginary component in the complex permeability characteristic of the magnetic loss material exists within a frequency range of 100 MHz to 10 GHz, and a relative bandwidth bwr is not greater than 200% or not smaller than 150% where the relative bandwidth bwr is obtained by extracting a frequency bandwidth between two frequencies at which the value of &#x3bc;&#x2033; is 50% of the maximum &#x3bc;&#x2033;and normalizing the frequency bandwidth at the center frequency thereof.

The present invention is a high-frequency current essentially of M&#x2014;X&#x2014;Y, where M is Fe, Co, and/or Ni, X is an element other than M or Y, and Y is F, N, and/or O. The maximum value &#x3bc;&#x2033;of the loss factor &#x3bc;&#x2033; of this material exists at 100 MHz to 10 GHz. A relative bandwidth bwr is not greater than 200% where the relative bandwidth bwr is obtained between two frequencies at which the value of &#x3bc;&#x2033; is 50% of &#x3bc;&#x2033;and normalizing the frequency bandwidth at the center frequency.

High-frequency current suppression body using magnetic loss material exhibiting outstanding complex permeability characteristics

In order to provide a wiring board comprising a magnetic material effective in suppressing spurious radiation in semiconductor devices and electronic circuits and the like that operate at high speeds, a wiring board () comprises an insulative base material (), conductor patterns (to) formed thereon, and magnetic thin films (to) formed on the conductor patterns (to). The magnetic thin film is configured of a magnetic loss material represented by M-X-Y, where M is at least one of Fe, Co, and Ni, X is at least one element other than M or Y, and Y is at least one of F, N, and O, the maximum value &#x3bc;&#x2033;max of the loss factor &#x3bc;&#x2033; that is an imaginary component in the complex permeability characteristic of the magnetic loss material exists within a frequency range of 100 MHz to 10 GHz, and a relative bandwidth bwr is not greater than 200% or not smaller than 150% where the relative bandwidth bwr is obtained by extracting a frequency bandwidth between two frequencies at which the value of &#x3bc;&#x2033; is 50% of the maximum &#x3bc;&#x2033;and normalizing the frequency bandwidth at the center frequency thereof.

A composite magnetic body is obtained without the use of halogen-based or halogen-containing materials, such as, halogen-based binding agent of halogen-based resins or elastomers, and bromine-based fire retardents. The composite magnetic body ( ) comprises a soft magnetic powder ( ) and a silicone rubber ( ). The silicone rubber ( ) should preferably be a solid silicone rubber. An electromagnet interference suppressing body is obtained using this composite magnetic body.

Composite magnetic body and electromagnetic interference suppressing body using the same

In order to provide a wiring board comprising a magnetic material effective in suppressing spurious radiation in semiconductor devices and electronic circuits and the like that operate at high speeds, a wiring board ( ) comprises an insulative base material ( ), conductor patterns ( to ) formed thereon, and magnetic thin films ( to ) formed on the conductor patterns ( to ). The magnetic thin film is configured of a magnetic loss material represented by M&mdash;X&mdash;Y, where M is at least one of Fe, Co, and Ni, X is at least one element other than M or Y, and Y is at least one of F, N, and O, the maximum value &mgr;&Prime;max of the loss factor &mgr;&Prime; that is an imaginary component in the complex permeability characteristic of the magnetic loss material exists within a frequency range of 100 MHz to 10 GHz, and a relative bandwidth bwr is not greater than 200% or not smaller than 150% where the relative bandwidth bwr is obtained by extracting a frequency bandwidth between two frequencies at which the value of &mgr;&Prime; is 50% of the maximum &mgr;&Prime; and normalizing the frequency bandwidth at the center frequency thereof.

In an electronic component ( ) comprising an electronic circuit or a circuit element in a metallic case including a case ( ) and a cover ( ), a magnetic thin film ( ) made of a magnetic loss material is provided on at least one part of an inner wall surface of the metallic case. In the magnetic loss material, its composition is represented by M-X&mdash;Y, wherein M denotes at least one of Fe, Co and Ni, X denotes at least one of elements other than M and Y, and Y denotes at least one of F, N and O. The maximum value &mgr;&Prime;max of an imaginary part &mgr;&Prime;, which is an imaginary number component of a complex permeability of the magnetic loss material, exists within a frequency range from 100 MHz to 10 GHz. A relative bandwidth bwr is not greater than 200% where the relative bandwidth bwr is obtained by extracting a frequency bandwidth between two frequencies at which the value of &mgr;&Prime; is 50% of the maximum &mgr;&Prime; and normalizing the frequency bandwidth at the center frequency thereof. It is possible to provide an electronic component including a metallic case, which contains a high-speed operation type of semiconductor device and/or an electronic circuit and in which undesired radiation is reduced.

Electronic component comprising a metallic case provided with a magnetic loss material

In a radiator ( ) for use in radiating heat generated by an electronic component ( ), a high-frequency current suppressor ( ) is attached to that principal surface of the radiator which faces the electronic component. The high-frequency current suppressor serves to attenuate a high-frequency current flowing through the radiator and having a frequency within a frequency band between several tens MHz and several GHz. It is preferable that a heat-conductive sheet is formed on the high-frequency current suppressor. An insulating sheet may be formed on the high-frequency current suppressor.

Radiator capable of considerably suppressing a high-frequency current flowing in an electric component

A composite magnetic body 1, comprising a soft magnetic powder ( ) and a binding agent ( ), in which the specific surface area of the soft magnetic powder ( ) is 0.1-3 m /g. The surface state of the soft magnetic powder contained in the composite magnetic body is defined in terms of specific surface area, and self-extinguishing properties, i.e. fire resistance properties, are obtained. An electromagnetic interference suppressing body is obtained using this composite magnetic body.

Composite magnetic body, and electromagnetic interference suppressing body using the same

A signal transmission cable ( ) having a conductor portion for transmitting signals and an insulator sheath ( ) covering the conductor portion, and a high loss magnetic film ( ) &lsqb;is&rsqb; formed on at least one part of the outer surface of the insulator sheath. The high loss magnetic film has the maximum complex permeability &mgr;&Prime; in a frequency range of 0.1-10 gigahertz (GHz). An example of a magnetic composition of the high loss magnetic film is a M-X-Y magnetic composition wherein M is a metallic magnetic material selected from among Fe, Co, and/or Ni, X is an element or elements other than M and Y, and Y is F, N, and/or O, the M-X-Y magnetic composition having a sufficient concentration of M in the composition so that the M-X-Y magnetic compostion has a saturation magnetization of 35-80% of that of the metallic magnetic material M alone.

Growing community of inventors

Yokohama, Japan

Yoshio Awakura