Hitachi Metals, Ltd.

Hitachi, Ltd.

Nippon Ferrite, Ltd.

Yasuhide Murakami

Kohei Ito

Shigeru Takeda

Yasuaki Kinoshita

Sadami Kubota

A magnetostatic wave microwave device comprising a thin magnetostatic wave element and a conductor disposed on the top of said magnetostatic wave element. Because the width of an junction portion of the conductor is larger than the width of an input portion of the conductor, a large impedance change of the magnetostatic wave element at resonance can be obtained while maintaining a Q-value at a high level.

Magnetostatic microwave device having large impedance change at resonance

A circuit element utilizing magnetostatic is formed with an acoustic wave absorbing layer on the other major surface of a non-magnetic substrate remote from the major surface where a magnetostatic wave propagation medium is formed, for the purpose of effectively suppressing an unnecessary spurious mode over a wide frequency band so as to obviate undesirable degradation of the resonance characteristic. That is, the circuit element utilizing the magnetostatic wave includes a thin film of YIG formed on one of the major surfaces of the non-magnetic substrate of GGG by the method of liquid phase epitaxial growth, and electrodes formed on the YIG thin film. In the circuit element, an acoustic wave absorbing layer is formed on the other major surface of the GGG substrate remote from the major surface where the YIG thin film is formed.

Magnetostatic wave device containing acoustic wave absorbing layer

A circuit element utilizing a magnetostatic wave is disclosed which uses a magnetostatic-wave resonator having a structure wherein a thin YIG (yttrium iron garnet) film is formed on a non-magnetic substrate such as a GGG (gadolium gallium garnet) substrate and defining a wave propagation plane. In this resonator, at least a part of end faces of the YIG film are inclined at an angle of 2.degree. or more to a plane perpendicular to the wave propagation plane to suppress the generation of unnecessary spurious modes in a wide frequency range.

Circuit element having ferrimagnetic film with deviated end surfaces for

A circuit element utilizing a magnetostatic wave is disclosed which uses a magnetostatic-wave resonator having a structure that a thin YIG (yttrium iron garnet) film is formed on a non-magnetic substrate such as a GGG (gadolinium gallium garnet) substrate. In this resonator, at least a part of end faces of the ferrimagnetic film are made rough such as by lapping with abrasives having a grain size greater than or equal to about 15 .mu.m, to suppress the generation of a unnecessary spurious mode in a wide frequency range.

Circuit element utilizing magnetostatic wave

A magnetostatic wave device has a nonmagnetic substrate, a magnetic thin film formed on the nonomagnetic substrate, and a plurality of electrodes. By applying a magnetic field from the outside in parallel with or perpendicularly to the magnetic thin film, a magnetostatic wave is excited in the magnetic thin film and is propagated. The magnetostatic wave is coupled with a microwave signal generating circuit by a plurality of (n) electrodes. The plurality which are arranged at positions where the microwave signal is not substantially coupled with the second to (n+l)th order mode of the magnetostatic wave.

Magnetostatic wave device with minimized higher order mode excitations

A magnetostatic wave device comprises a magnetic thin film formed on a non-magnetic substrate, one or a plurality of electrode fingers and pad electrodes formed on the above described magnetic thin film, a magnetostatic wave resonator for exciting and propagating a magnetostatic wave within said magnetic thin film and for causing resonance, and a matching stub connected to at least one of the above described pad electrodes of the above described magnetostatic wave resonator to adjust the impedance of the magnetostatic wave device.

Growing community of inventors

Kumagaya, Japan

Yasuhide Murakami