JPH0634305U - Magnetostatic wave resonator - Google Patents

Abstract

(57) [Summary] (Modified) [Purpose] To improve the phase noise of an oscillator using a magnetostatic wave resonator. [Structure] A ferrimagnetic thin film 2 is formed on a non-magnetic substrate 1 by a liquid phase epitaxial growth method, and electrode fingers 6 are formed on the thin film 2.
Of the magnetostatic wave propagating on either one of the reflection end faces 7a and 7b through which the magnetostatic wave propagates.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a magnetostatic wave resonator using magnetic spin resonance of a ferrimagnetic thin film such as YIG (yttrium, iron, garnet) formed on a non-magnetic substrate such as GGG (gadolinium, gallium, garnet), an oscillator, etc. When used for, it improves the phase noise.

[0002]

[Prior art]

 There has been proposed a ferrimagnetic thin film magnetostatic wave resonator obtained by processing a liquid phase epitaxially grown YIG thin film into a required shape on a GGG non-magnetic substrate. 2A and 2B show a structure of a conventional magnetostatic wave resonator. In the figure, a magnetostatic wave resonator is formed by forming a YIG thin film 2 on a GGG substrate 1 by a liquid phase epitaxial method, and further forming one or a plurality of electrode fingers 3 made of Au or Al film on these thin films and these electrodes. The pad electrodes 4a and 4b are formed on both sides of the electrode finger 3 by a photo-etching technique. The pad electrodes 4a and 4b are diced to a desired size, and are placed on the dielectric substrate 5. Here, the electrode fingers 3 are calculated so that unnecessary resonance modes and the like are removed, have regular arraying, and are formed so as to be line-symmetric with respect to the center line XX. The magnetostatic wave resonator is used as a resonator such as an oscillator by utilizing the fact that a magnetostatic wave is excited when a magnetic field is applied to the YIG thin film 2 from the outside perpendicularly to the magnetostatic wave resonator.

[0003]

[Problems to be solved by the device]

 Precision is required to process without breaking the arrangement and symmetry of the electrode fingers as described above, but the precision may be slightly different depending on the work, which causes variations and deterioration in the resonance characteristics of the magnetostatic wave resonator. As a result, there was a problem that the phase noise of the oscillator deteriorates. As a result of measuring the phase noise of the oscillator at this time, the result is as shown in FIG.

[0004]

[Means for Solving the Problems]

 In order to solve the above problems, the present invention forms a ferrimagnetic thin film on a nonmagnetic substrate, forms one or more electrode fingers and a pad electrode on the ferrimagnetic thin film, and A magnetostatic wave resonator having a structure that excites, propagates, and resonates a magnetostatic wave in the microwave band, and is formed by the electrode fingers concentrated on one of the reflection end faces through which the magnetostatic wave propagates. It is a magnetostatic wave resonator characterized by being used.

[0005]

【Example】

 Hereinafter, the present invention will be described in detail based on embodiments. 1A and 1B are views showing an embodiment of the present invention. A Y IG thin film 2 is formed on a GGG substrate 1 by a liquid phase epitaxial method, and one or a plurality of electrode fingers 6 made of Au or Al film are formed on this thin film and both sides of these electrode fingers 6 are formed. The pad electrodes 4a and 4b are formed by a photo-etching technique, and are diced into a desired size, and placed on the dielectric substrate 5. Here, as shown in FIG. 1B, the electrode fingers 6 are formed in a concentrated manner on the side of the reflection end face 7a where the magnetostatic wave propagates. A magnetostatic wave resonator having such a structure is used as a resonator, and an oscillator is produced to measure the phase noise. The result is as shown in FIG. It was confirmed that the phase noise was improved. In addition, the deterioration of phase noise due to the processing accuracy of the resonator, which is seen in oscillators using conventional magnetostatic wave resonators, was not observed. Further, in the present embodiment, the electrode fingers 6 are formed on the side of the reflection end surface 7a, but the same effect can be obtained even when the electrode fingers 6 are concentrated on the side of the other reflection end surface 7b.

[0006]

[Effect of device]

 As described above, according to the present invention, the electrode fingers formed on the ferrimagnetic thin film of the magnetostatic wave resonator are concentrated on either one of the reflection end faces through which the magnetostatic wave propagates. It is possible to improve the phase noise of the oscillator by suppressing the variation and deterioration of the resonance characteristic due to the processing accuracy.

[Brief description of drawings]

FIG. 1A is a perspective view showing an embodiment according to the present invention, and FIG. 1B is a plan view.

FIG. 2 (a) is a perspective view according to the related art, and FIG.
Is a plan view.

FIG. 3A is a frequency characteristic diagram of phase noise of an oscillator according to the present invention, and FIG. 3B is a frequency characteristic diagram of phase noise of an oscillator according to the related art.

[Explanation of symbols]

 1 GGG substrate 2 YIG thin film 3, 6 Electrode fingers 4a, 4b Pad electrode 5 Dielectric substrate 7a, 7b Reflection end face

Claims (1)

[Scope of utility model registration request] 1. A ferrimagnetic thin film is formed on a non-magnetic substrate, and one or more electrode fingers and a pad electrode are formed on the ferrimagnetic thin film so that a microwave band is formed inside the ferrimagnetic thin film. A magnetostatic wave resonator having a structure that excites, propagates, and resonates a magnetostatic wave, characterized in that the electrode fingers are formed in a concentrated manner on either one of the reflection end faces through which the magnetostatic wave propagates. Magnetostatic wave resonator.