JP2674364B2 - Chip type stripline resonator - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resonator formed by using a strip line, and more particularly to a chip type strip line resonator used as a high frequency resonator or a filter.

[0002]

2. Description of the Related Art Conventionally, as a high frequency filter, elements such as a laminated LC filter 1 shown in FIG. 7 and a dielectric filter 2 shown in FIG. 8 have been widely used. The laminated LC filter 1 is formed by using a laminated body 3 obtained by printing a conductive pattern on a plurality of ceramic sheets to form independent inductance L and capacitance C, and laminating these. ing. In addition, 4a to 4h denote terminal electrodes, and the inductance L built in the laminated body 3
And the capacitor C are formed to electrically connect to the outside.

The dielectric filter 2 comprises a plurality of dielectric resonators each having an inner conductor 6 formed in a through hole of a rectangular cylindrical dielectric 5 made of a dielectric ceramic and an outer conductor 7 formed on an outer peripheral surface thereof. It is constructed by joining and is usually constructed as a part housed in a case (not shown).

[0004]

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention
In the filter 1, when trying to obtain a filter used in a higher frequency range, there is a limit to increase the upper limit of the frequency.
In addition, there is a limit to increase the Q value, and even in the case of further miniaturization, there is a limit because it includes a plurality of independent elements. On the other hand, in the dielectric filter 2 shown in FIG. 8, it is easy to increase the frequency. However, since it has a structure in which a plurality of dielectric resonators are joined and further housed in a case, there is a problem in that it is inevitably large as a component and the cost is high.

Therefore, an object of the present invention is to provide a chip type resonance device which can be used in a higher frequency range and which constitutes a small and inexpensive high frequency filter.

[0006]

According to the present invention, a dielectric substrate is provided on one main surface thereof from one edge of the dielectric substrate to the other edge thereof.
The first part and the second part branched from the middle of the first part
The stripline conductor having a portion, a strip line resonator formed by forming an earth electrode on the other main surface, and reinforcing insulating substrate bonded to the other major surface of the dielectric substrate of the strip line resonator, said strip First and second electrically connected to both ends of the first portion of the line conductor
And a third terminal electrode electrically connected to the ground electrode, which is a chip-type stripline resonance device.

[0007]

According to the present invention, since is to use a stripline resonator as described above, it is possible to provide a distributed constant type resonator for high frequency. Further, since the stripline resonator is used, the stripline conductor, the ground electrode, and each terminal electrode are merely configured by being formed on the dielectric substrate or the insulating substrate. The size can be easily reduced. Addition
Therefore, the stripline conductor is one of the dielectric substrates.
The first portion from the edge to the other edge, and the way of the first portion
The second part because it has a second part branched from inside
Connect or disconnect to the ground electrode as required
To obtain a parallel resonator or series resonator easily.
Can be. In addition, a reinforcing insulating substrate is added to the dielectric substrate.
Since they are bonded, the mechanical strength of the chip type resonator is improved.
Enhanced. Also, since it is a distributed constant type resonance device,
It can be applied to the microwave region, and thus a resonator and a filter that can be used in a higher frequency region can be configured.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A chip type stripline resonator according to an embodiment of the present invention will be described below. 1 and 2
FIG. 3 is a partially cutaway perspective view showing the chip type stripline resonator of the present embodiment and a plan view showing a part of the upper portion cut away. Chip-type stripline resonator 11 of the present embodiment
Has a structure in which a quarter-wave stripline resonator is formed by using a rectangular plate-shaped dielectric substrate 12, and an insulating substrate 13 is bonded to the dielectric substrate 12.

As shown in FIG. 3A, stripline conductors 14 are formed on the upper surface of the dielectric substrate 12. The stripline conductor 14 has a linear first portion 14a formed so as to extend from the one end surface 12a of the dielectric substrate 12 to the other end surface 12b thereof, and is branched from the middle of the first portion 14a and has a meandering shape. And the formed second portion 14b. On the other hand, a ground electrode 15 is formed on the lower surface of the dielectric substrate 12 so as to face the stripline conductor 14 as shown in FIG. In the chip type stripline resonator 11 of the present embodiment, the stripline conductor 14 and the ground electrode 15 are formed on the dielectric substrate 12 to form a quarter wavelength stripline resonator.

Returning to FIGS. 1 and 2, a protective film 16 is formed on the upper surface of the dielectric substrate 12. The protective film 16 is
It is formed to insulate and protect the stripline conductor 14 formed thereunder, and may be made of an appropriate insulating resin film. Further, the insulating substrate 13 is attached to the lower surface side of the dielectric substrate 12 using an adhesive 17. The insulating substrate 13 is provided to provide mechanical strength. Therefore, the insulating substrate 13 can be made of, for example, ceramics such as alumina, a resin having high rigidity, an insulating coated metal plate, or the like.

As described above, the dielectric substrate 12 and the insulating substrate 1
Terminal electrodes 18, 19, 20, and 21 are formed on the outer surface of the laminated body obtained by bonding 3 together. Of these, the terminal electrode 18 and the terminal electrode 20 are formed so as to be electrically connected to both ends of the stripline conductor 14, while the terminal electrodes 19 and 21 are electrically connected to the ground electrode 15. Is formed.

By the way, in the case of miniaturizing the chip type stripline resonance device 11 of the above embodiment, 1
It is preferable that the length of / 4 wavelength is shorter. Therefore, the larger the dielectric constant of the dielectric material forming the dielectric substrate 12, the more preferable, and at least 50 or more, preferably 1
It is preferably 00 or more. However, if the size of the quarter-wavelength is shortened and the dielectric substrate 12 is made of a material having a dielectric constant of 100 or more as described above, the thickness of the dielectric substrate 12 is inevitably 0.2 to 0. It is considerably thin, about 3 mm. Further, the width of the quarter-wave strip line conductor 14 also needs to be narrowed to about 20 to 30 μm.

Therefore, in this embodiment, in order to supplement the mechanical strength of the dielectric substrate 12, the insulating substrate 13 made of the rigid material described above is bonded to the dielectric substrate 12 using the adhesive 17. Further, since it is necessary to make the width of the stripline conductor 14 considerably small, the stripline conductor 14 is formed by using a thin film forming technique. As a result, in the chip-type stripline resonance device 11 of the present embodiment, when an attempt is made to obtain a filter having a center frequency of 880 MHz, 3.2 × 1.6 × thickness 0.6 to
It has become possible to configure it as an ultra-small component of 0.9 mm.

Next, a method for manufacturing the chip type stripline resonator of the above embodiment will be described. First, the dielectric substrate 12 was prepared, the stripline conductor 14 was formed on the upper surface by sputtering, and then the ground electrode 15 was formed on the back surface by sputtering. Then, a protective film 16 was formed on the upper surface of the dielectric substrate 12 so as to cover the stripline conductor 14 (see FIG. 4).

Further, as shown in FIG. 5, the ground electrode 1
5 and the pair of extraction electrodes 22 so as to be electrically connected to the dielectric substrate 12 and reach the end surfaces 12a and 12b of the dielectric substrate 12.
a and 22b are formed. Note that the extraction electrodes 22a, 22
b is formed in the same width as the terminal electrodes 19 and 21 shown in FIGS. Also, as is clear from FIG.
The extraction electrodes 22 a and 22 b are formed so as to reach the protective film 16 and are formed so as not to be electrically connected to the stripline conductor 14. The extraction electrodes 22a and 22b were formed by performing double-sided partial sputtering or single-sided partial sputtering twice. Next, after forming the extraction electrodes 22a and 22b, the dielectric substrate 12 and the insulating substrate 13 having a thickness of about 0.4 to 0.6 mm were bonded with the adhesive 17. Finally, the terminal electrodes 18 to 21 were formed by the same sputtering method.

An equivalent circuit of the chip type stripline resonator of this embodiment obtained as described above is shown in FIG. 6 (a).
Shown in In the stripline resonator of this embodiment, the terminal electrodes 18 and 20 are used as input / output terminals, and the terminal electrodes 19 and 21 are used.
Can be operated as a high-frequency filter by connecting to the reference potential.

Incidentally, in the above embodiment, FIG. 2 and FIG.
As shown in FIG. 3A, the stripline conductor 14 is configured as a short-circuited tip type. For example, as shown in FIGS.
By forming the second portion 14b of the stripline conductor 14 so as to have a length up to the portion indicated by the alternate long and short dash line A, an open-ended 1/4 wavelength stripline resonator can be constructed. FIG. 6B shows an equivalent circuit of the open-ended quarter-wave resonator configured as described above. The dielectric substrate 12 and the insulating substrate 13 may be joined together by, for example, a vacuum hot pressing method.

[0018]

As described above, according to the present invention, the dielectric
A first portion from the first edge of the substrate to the second edge;
Since the resonance device is configured using the stripline resonator having the second portion branched from the middle of the first portion , the second portion is connected to the ground electrode as necessary.
Alternatively, simply disconnect them to create a parallel resonator or series.
A resonator can be easily obtained, and a smaller and cheaper resonator device can be provided. In addition, since it has a distributed constant type configuration, it is possible to handle microwave regions, and it is also possible to increase the Q value as compared with the conventional lumped constant type resonance device.

Further, in the stripline resonance device of the present invention, the thickness of the dielectric substrate becomes very thin with the miniaturization, but since the reinforcing insulating substrate is bonded as described above, the mechanical strength is also increased. Since it is sufficient, it can be supplied as a chip type component having sufficient strength.

[Brief description of the drawings]

FIG. 1 is a partially cutaway perspective view showing a chip type stripline resonator according to an embodiment of the present invention.

FIG. 2 is a plan view showing a part of an upper portion of the chip type stripline resonator shown in FIG.

3A is a plan view for explaining a stripline conductor formed on the upper surface of a dielectric substrate, and FIG. 3B is a plan view showing a ground electrode formed on the lower surface of the dielectric substrate.

FIG. 4 is a cross-sectional view showing a state in which a protective film is formed after the stripline conductor and the ground electrode are formed.

FIG. 5 is a cross-sectional view showing a state in which a lead electrode connected to a ground electrode is formed.

6A and 6B are diagrams respectively showing an equivalent circuit of a chip type stripline resonance device obtained in an example of the present invention.

FIG. 7 is a perspective view for explaining a conventional laminated LC filter.

FIG. 8 is a perspective view for explaining the configuration of a conventional dielectric filter.

[Explanation of symbols]

 11 ... Chip type stripline resonator 12 ... Dielectric substrate 13 ... Insulating substrate 14 ... Stripline conductor 15 ... Earth electrodes 18-21 ... Terminal electrodes

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Takashi Makita, 26-10 Tenjin, Tenjin, Nagaokakyo, Kyoto Prefecture Murata Manufacturing Co., Ltd. (56) References JP-A-53-73053 (JP, A) JP-A 2-158156 (JP, A) Actual Kaihei 1-78401 (JP, U)

Claims (1)

(57) [Claims] 1. A dielectric substrate, are made form on one main surface of the dielectric substrate, the other end from one end edge of the dielectric substrate
Branched from the first part to the edge and the middle of the first part
And a stripline conductor having a second portion, said having a dielectric ground electrode formed on the other main surface of the substrate, scan and stripline resonators, the other main dielectric substrate of the strip line resonator A reinforcing insulating substrate joined to the surface, first and second terminal electrodes formed so as to be electrically connected to both ends of the first portion of the stripline conductor, and an electrical connection to the ground electrode. And a third terminal electrode formed so as to be connected to the chip type stripline resonance device.