JPH11214908A - Dielectric resonator and dielectric resonator device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a dielectric resonator which readily enhances the positional accuracy of the dielectric resonator, especially against a mounted substrate and also enhances productivity and a dielectric resonator device that uses it. SOLUTION: This dielectric resonator 2 in a TE010 mode is configured by forming electrodes which has opening parts that face opposite to each other on both principal planes of a dielectric plate 22 and plural conductive projecting parts for jointing are formed on the electrodes of the dielectric plate. The resonator 2 is mounted on electrodes 29 for mounting on the plate 1 through the conductive projecting parts for joining.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a dielectric resonator used in a microwave band or a millimeter wave band and a dielectric resonator device using the same.

[0002]

2. Description of the Related Art With the recent increase in demand for mobile communication systems and the amount of transmitted information, the communication band is being expanded from the microwave band to the millimeter wave band. When configuring an oscillator in such a high frequency band, a dielectric resonator is used as the resonator.

FIG. 8 is an exploded perspective view showing the structure of a conventional oscillator. In FIG. 1, reference numeral 1 denotes a mounting board, on which a variety of conductor patterns such as microstrip lines 8 are formed, and an FET 7 is mounted thereon to form an oscillation circuit. The dielectric resonator 42 is arranged through the intermediary. By mounting such a mounting substrate 1 on the stem 40 and covering with a cap 41, the entire periphery of the dielectric substrate 1 is shielded.

[0004]

SUMMARY OF THE INVENTION Such TE01δ
In a conventional oscillator using a mode dielectric resonator, the resonance frequency of the dielectric resonator is determined by the relative permittivity and the outer dimensions of the cylindrical dielectric, and the coupling with the microstrip line is established between the dielectric resonators. , High dimensional accuracy is required for the dielectric resonator 42 and the support 43, and the dielectric resonator 4 is placed on the dielectric substrate 1.
2 high positioning accuracy is required. In addition, when the coupling between the microstrip line 8 and the dielectric resonator 42 is changed, the magnetic field distribution of the dielectric resonator 42 spreads around. Since the resonator 42 is coupled to other lines other than the microstrip line 8 and the oscillation condition is changed, the coupling between the dielectric resonator 42 and the microstrip line 8 cannot be changed independently. Therefore, there is a problem that the reproducibility of the coupling degree due to the positional relationship between the dielectric resonator 42 and the microstrip line 8 is poor, and it is difficult to obtain stable characteristics.
In addition, since the TE01δ mode dielectric resonator has a relatively low energy confinement property in the dielectric portion, a certain distance must be provided to prevent unnecessary coupling with a line other than a predetermined microstrip line. In addition, there is a problem that miniaturization becomes difficult as a whole.

Accordingly, the applicant of the present application has filed a Japanese Patent Application No. 7-6262.
No. 5 (Japanese Unexamined Patent Publication No. 8-265015) proposes a dielectric resonator and a dielectric filter which solve these problems and are excellent in processing accuracy.

In the dielectric resonator and the dielectric filter according to the above-mentioned application, a part of the dielectric plate is used as a dielectric resonator by forming electrodes on both main surfaces of the dielectric plate. In such a dielectric resonator, an electrode formed on the dielectric plate can be used as a ground electrode. Therefore, it is necessary to form a microstrip line or the like on a mounting substrate and mount the dielectric resonator. Thereby, a high-frequency module such as an oscillator including the dielectric resonator and the electronic component can be configured. FIG. 9 shows an example of the configuration.
(A) is a perspective view, (B) is a sectional view, and the dielectric plate 22 is shown.
The electrodes 23, 24 having circular openings 25, 26 facing each other are formed on both main surfaces of the electrodes 23, 24. Thus, a TE010-mode dielectric resonator is formed at the electrode opening.

Such a dielectric resonator is, for example, shown in FIG.
As shown in FIG. 0, when the dielectric resonator 2 is mounted on the mounting electrode 29 formed on the mounting substrate 1 via a conductive adhesive, a dielectric resonator device such as an oscillator is configured. .
In this state, the line 8 formed on the mounting substrate 1 and the dielectric resonator 2 are electromagnetically coupled.

[0008]

However, since the conductive adhesive has a relatively low viscosity and requires a curing process, the dielectric resonator formed on the dielectric plate as described above is replaced with the conductive adhesive. When mounting on a mounting substrate by using the same, it is difficult to increase the accuracy of the mounting position of the dielectric resonator with respect to the mounting substrate and the accuracy of the thickness dimension of the adhesive to a certain degree or more. Therefore, the degree of coupling between the dielectric resonator and the line varies. In addition, the conductive adhesive may protrude into the electrode opening constituting the resonator portion, and may impair characteristics such as a change in resonance frequency.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned various problems in the prior art, and in particular, to improve the positional accuracy of a dielectric resonator with respect to a mounting substrate easily and to enhance the productivity. An object of the present invention is to provide a resonator and a dielectric resonator device using the same.

[0010]

According to the present invention, there is provided a dielectric resonator in which electrodes having openings facing each other are formed on both main surfaces of a dielectric plate, and the openings are used as resonator portions. And forming a plurality of bonding conductor protrusions on the electrodes of the dielectric plate.

By using the dielectric resonator having this structure, the dielectric resonator can be easily bonded to the electrode on the mounting substrate via the bonding conductor protrusion. Further, if the gap between the dielectric resonator and the mounting substrate facing each other is filled with resin, the bonding strength between the two can be increased, and the reliability thereof can be improved.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The configuration of an oscillator according to a first embodiment of the present invention will be described with reference to FIGS.

FIG. 1 is an exploded perspective view of the oscillator. In the figure, reference numeral 40 denotes a stem, and a pin 1 moves downward in the figure.
6, 17, and 18 are projected in an insulated state.
The fixing screws 20 and 21 project in the same direction. On the upper portion of the stem 40, a mounting substrate 1 on which various conductive patterns are formed and components are mounted is placed.
In addition, a cap 41 is placed over the stem 40 to shield the periphery of the mounting substrate 1.

On the lower surface of the mounting board 1 in the drawing,
A ground electrode is formed on almost the entire surface, avoiding a portion where 6, 17, 18 pass.

In FIG. 1, reference numeral 2 denotes a TE010-mode dielectric resonator in which electrodes having circular openings facing each other are formed on both main surfaces of a dielectric plate 22. 23 is an electrode on the upper surface of the dielectric plate 22, and has a circular opening 25 at the center thereof.

On the upper surface of the mounting substrate 1, reference numeral 8 denotes a microstrip line, which is coupled to the TE010 mode of the dielectric resonator 2 at a predetermined position. 7 is an FET,
One end of the microstrip line 8 is connected to the microstrip lines 4 and 11, respectively. Reference numeral 5 denotes a ground electrode, and a chip resistor 6 is mounted between the ground electrode 5 and the microstrip line 4. A capacitance is formed on the substrate between the microstrip lines 4 and 3, and an electrode 15 extending from the microstrip line 3 is connected to the pin 17 as an output electrode. Microstrip line 1
1 and the input electrode 14 are connected by a microstrip line 12 as an inductor. The chip capacitor 13 is mounted between the input electrode 14 and the ground electrode 5. Reference numeral 10 denotes an earth electrode, and a chip resistor 9 as a terminating resistor is mounted between the other end of the microstrip line 8 and the earth electrode 10.

On the upper surface of the mounting substrate 1, a mounting electrode 29 of the dielectric resonator 2 is further formed. Numeral 30 is a through hole for conducting between the mounting electrode 29 and the ground electrode on the back side of the mounting substrate 1.

FIG. 2B is a diagram showing an electromagnetic field distribution of the dielectric resonator 2. In the figure, the curves show the magnetic field distribution. Thus, by forming electrodes having circular openings facing each other on both main surfaces of the dielectric plate, the dielectric plate functions as a TE010 mode dielectric resonator.

FIG. 2A is a perspective view of the dielectric resonator. Here, the mounting surface for the mounting substrate is shown as the upper surface. In the figure, reference numeral 28 denotes a through hole for conducting between the electrode 24 on the upper surface and the electrode on the lower surface of the dielectric plate 22 in the figure. Reference numeral 27 denotes bonding conductor protrusions (bumps) that protrude by a predetermined height. The bonding conductor projection 27 can be formed by plating the electrode 24. For example, if the electrode 24 is Au
A resist film is formed as an electrode, and an opening is formed at a position where a conductive projection for bonding is formed.
An electrode or Cu electrode may be applied by a predetermined plating thickness, and then the resist film may be removed.

FIG. 3 is a partial sectional view showing a state where the dielectric resonator is mounted on the mounting substrate. The ground electrode 19 on the lower surface side of the mounting substrate 1 and the mounting electrode 29 on the upper surface side are connected via a through hole 30. This mounting electrode 2
The dielectric resonator 2 is mounted on the surface of the substrate 9 via the bonding conductor protrusion 27. At this time, bonding is performed by thermocompression bonding, ultrasonic compression bonding, or an ultrasonic thermocompression bonding method using both of them.
In addition, at this time, the bonding conductor protrusion 27 is crushed by a certain amount, and the distance between the line 8 on the mounting substrate 1 and the dielectric resonator 2 is determined. Since the degree of coupling between the dielectric resonator and the line changes depending on this distance, the joining conductor protrusion 2 at the time of crimping is used.
If the height (thickness dimension) is determined in advance in consideration of the collapse size of 7, the degree of coupling can be made constant. Further, the degree of coupling between the dielectric resonator and the line may be positively changed by controlling the crushing size of the bonding conductive projection 27 during the pressure bonding. That is, so as to obtain a predetermined degree of coupling,
The pressure, the amount of heating, and the amount of ultrasonic energy injected during the pressing may be controlled.

FIG. 4 is an overall equivalent circuit diagram of the oscillator. The numbers in the figure correspond to the numbers of the respective parts shown in FIG. As shown in FIG. 4, one end of the line 8 is terminated by a resistor 9, and the other end is connected to the gate of the FET 7. The power supply input voltage is applied to the drain of the FET 7 through a filter including the chip capacitor 13 and the inductor 12. The oscillation signal is extracted from the source of the FET 7 to the output terminal via the capacitor. Thus, a band reflection type oscillation circuit is formed.

FIG. 5 is a sectional view of a main part of the dielectric resonator device according to the second embodiment. In the example shown in FIG. 3, the line coupled to the dielectric resonator is provided on the mounting surface side of the dielectric resonator, but as shown in FIG. 5, the back surface of the mounting substrate 1 (the mounting surface of the dielectric resonator 2) Alternatively, the line 8 may be formed on the surface on the side opposite to the above) and coupled. In this case, the line 8 may constitute a coplanar line together with the ground electrodes 19 on both sides thereof.

FIG. 6 is a sectional view of a main part of the dielectric resonator device according to the third embodiment. Although the structures of the mounting substrate 1 and the resonator 2 are the same as those shown in FIG. 3, in this example, after the resonator 2 is bonded to the mounting substrate 1 via the bonding conductive protrusion 27, the dielectric By filling the gap between the body resonator 2 and the mounting substrate 1 facing each other with, for example, an epoxy-based resin 51, the entire joining portion formed by the joining conductor protrusions is resin-sealed. With this structure, the overall bonding strength between the mounting substrate 1 and the dielectric resonator 2 is increased, and the reliability thereof is increased.

FIG. 7 is an equivalent circuit diagram of the VCO according to the fourth embodiment. In the first to third embodiments, a single line is coupled to the dielectric resonator. However, two lines are formed on the mounting board in the same manner, and the dielectric resonator is mounted. By arranging the two lines so that the two lines are coupled to the dielectric resonator, the two lines can be used as a VCO as shown in FIG. Line 8 in FIG.
, The line 31 acts as a sub-line, the inductor 34, the resistor 35 and the capacitor 37 act as an RF filter, and the capacitance of the varactor diode 32 changes according to the control input voltage. The capacitance changes, and the oscillation frequency of the FET 7 changes accordingly.

In the above example, the plating method
In addition to the formation of the joining conductor protrusion, after forming an electrode having a constant thickness up to, for example, the height of the joining conductor protrusion, etching is performed by a predetermined amount except for a portion to be the joining conductor protrusion. By doing so, the joining conductor protrusion may be formed. Alternatively, for example, a bump may be formed on a temporary substrate in advance, and the bump may be transferred onto the electrode surface of the dielectric resonator to provide a bonding conductor protrusion. Also, Sn-Pb solder or In-Pb solder is used as the material of the conductor projection for bonding, and when the dielectric resonator is mounted, the dielectric resonator is mounted on the mounting substrate by heating and melting the solder. Is also good. Furthermore, using a wire bonder, a ball is formed at the tip of the Au wire by electric discharge, this is pressed on the electrode of the dielectric resonator, and then torn off to form an Au bump on the electrode of the dielectric resonator. Is also good.

In each of the embodiments, the TE010-mode dielectric resonator is formed by providing circular openings facing each other on both main surfaces of the dielectric plate. However, openings having other shapes such as rectangles are provided. Is also good. Further, in the embodiment, the example in which the dielectric resonator is mounted at a position overlapping with the line on the mounting board has been described, but the dielectric resonator may be mounted close to the line on the mounting board.

Further, in the embodiment, the pin type dielectric resonator device in which the pins protrude from the stem is shown. However, as a case for housing the mounting substrate and the dielectric resonator, the mounting electrodes are exposed to the outside. A surface-mount type dielectric resonator device may be formed by using such a device.

[0028]

According to the first and second aspects of the present invention, the dielectric resonator can be easily mounted on the electrode on the mounting substrate via the bonding conductor protrusion.

According to the third aspect of the present invention, the bonding strength between the dielectric resonator and the mounting substrate is increased, and the reliability thereof can be improved.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view showing a configuration of an oscillator according to a first embodiment.

FIG. 2 is a perspective view of a dielectric resonator and a diagram showing a state of an electromagnetic field distribution.

FIG. 3 is a partial cross-sectional view in a state where a dielectric resonator is mounted on a mounting substrate.

FIG. 4 is an equivalent circuit diagram of an oscillator.

FIG. 5 is a partial cross-sectional view of a dielectric resonator device according to a second embodiment.

FIG. 6 is a partial cross-sectional view of a dielectric resonator device according to a third embodiment.

FIG. 7 is an equivalent circuit diagram of a VCO according to a fourth embodiment.

FIG. 8 is an exploded perspective view showing a configuration of a conventional oscillator.

FIG. 9 is a perspective view and a sectional view of a dielectric resonator.

FIG. 10 is a sectional view of a main part of an apparatus using the dielectric resonator.

[Explanation of symbols]

 Reference Signs List 1-Mounting substrate 2-Dielectric resonator 3,4-Microstrip line 5-Earth electrode 6-Chip resistance 7-FET 8-Line (main line) 9-Chip resistance 10-Earth electrode 11,12-Microstrip line 13-chip capacitor 14-input electrode 15-output electrode 16-18-pin 19-ground electrode 20,21-screw 22-dielectric plate 23,24-electrode 25,26-opening 27-joining conductor protrusion 28-through hole 29-mounting electrode 30-through hole 31-microstrip line (sub line) 32-varactor diode 40-stem 41-cap 42-dielectric resonator 43-support base

Claims (3)

[Claims] 1. A dielectric resonator in which electrodes having openings facing each other are formed on both main surfaces of a dielectric plate, and the openings are used as resonator portions. A dielectric resonator comprising a plurality of bonding conductor protrusions. 2. A dielectric resonator device formed by joining the dielectric resonator according to claim 1 to an electrode on a mounting substrate via the conductive projection. 3. A resin is filled in a gap between the dielectric resonator and the mounting board facing each other.
3. The dielectric resonator device according to claim 1.