JPS6030208A - Ceramic resonator - Google Patents

Abstract

PURPOSE:To obtain a high resonance frequency by sintering plural piezoelectric ceramic layers in one body while a single electrode layer is put internally and obtaining a laminate sinter, and making a polarization direction coincident with the layer direction. CONSTITUTION:Electrode paste layers 12a-12b, and 13a-13b are formed on top surfaces of green sheets 11b-11e of piezoelectric ceramics, and those green sheets 11a-11e are stacked and united by thermal press contacting. The united laminate is baked in air or an oxygen atmosphere. At this time, the electrode paste layers turn into electrode layers. Polarizing electrodes are formed on top and reverse surfaces of the sinter and a polarizing electric field is applied to perform polarization. When electrodes 14 and 15 for external connections are regarded as a plus and a minus electrodes respectively, the ceramic layers 11c and 11e extend in the thickness direction and the ceramic layers 11b and 11d contract in the thickness direction, so oscillation in the thickness direction occurs. Even when each layer is thick, strength is obtained on the whole, so the resonator is used in a high frequency range.

Description

[Detailed Description of the Invention] ↓ This 5 relates to ceramic resonance, and 1!1 relates to a laminated ceramic resonator.

It is used for applications such as Reramic co-packed Reramic filters and Reramitsuta oscillators, and as the frequency range expands, the vibration modes become more diverse. J, radial vibration, thickness vibration, thickness confinement vibration, etc. are used. In the high frequency range, thickness confinement vibration is used, but resonance 11
As the wave number gets higher, you should not give up on your worries. For example, 1) If the thickness of the ZT-based piezoelectric ceramic is 200 μm, the resonant frequency is 10M+-12, and if the P7 diameter is 100 μm, the resonant frequency is 20
Approximately corresponds to M l-l z.

However, since element No. 6 is made of ceramic, there is a limit to how thin the element can be made, and when it reaches 13◇00μ, it becomes very difficult to mechanically hold the rim.

However, by making the piezoelectric ceramic a laminated type, arranging an electrode layer on the piezoelectric ceramic layer, and roughly arranging the polarization direction of the piezoelectric ceramic in a constant direction, it was possible to create a ceramic resonator that can be used in high frequency ranges. I can do it.

That is, an object of the present invention is to provide a ceramic resonator that can be used in a high frequency region.

This invention can be summarized as follows. That is, a plurality of piezoelectric ceramic layers are stacked and sintered into an integrated surface to form an IC laminate, and a plurality of single electrode layers are formed parallel to the piezoelectric ceramic layers and extending to the ends of the laminate. The piezoelectric ceramic layer is polarized in the same direction as the stacked thickness 75, and an external connection electrode is laminated to be electrically connected to the )ff part of the electrode layer exposed on the end face of the laminate. formed at the ends of the body,
This is a ceramic resonator that is characterized by:

This defense will be explained in detail below according to an illustrated embodiment.

FIG. 1 is a cross-sectional view of a stacked remic resonator according to the present invention.

In the figure, a3-C111 indicates a piezoelectric ceramic layer, and a plurality of layers are laminated as shown in the figure to form the laminate 10.

Reference numerals 12 and 13 indicate a single electrode layer interposed between the piezoelectric ceramic layer 11 and the single electrode @ 12 and 13 intersecting! :j, the end portions of which are the end surfaces 10a, 101+ of the laminate 10
It is formed to extend to. Reference numeral 111.15 indicates external connection electrodes, which are formed on the end surfaces 10a and 10b of the stacked body 10.

These external connection electrodes 14.15 are therefore electrically connected to the single electrode layer 12.13. The polarization direction of the piezoelectric ceramic layer 11 constituting the laminate 10 is the direction of the illustrated arrow P, which is the same direction as the thickness direction of the piezoelectric ceramic layer 11.

Next, the manufacturing process of a ceramic resonator with such a structure is shown in Figure 2.

First, piezoelectric ceramic green seal l-11a~11
Prepare e. Among these green sheets 1 to 11a to lie, except for the uppermost green sheet 1 to 11a, an electrode paste layer 1 is formed on the upper surface of each green sea +-11b to 11e.
2a to 12b and 13a to 13b are formed.

Electrode paste layers 12a to 12b, 13a-131+
Illustrate scenes 11a to 11e.
The carts are stacked in this direction and integrated using a heat pressure shield. Thereafter, the integrated laminate is fired in air or an oxygen atmosphere to form a sintered body. At this time, the electrode paste 1 layer 12a~
121+, 13a to 131] are fired at the same time and become electrode layers.

Next, electrodes for polarization are formed on the upper and lower surfaces of the sintered body. This electrode is formed by a commonly used heat-bonded electrode of the type 41.

Then, a 14i electric field (EeX) is applied so that the 14i electric field (EeX) is oriented in the same direction as the thickness direction in which the Green Sea 1- is stacked. In order to polarize the raccoon in this way, J, - C, which was small in Figure 1, J] - Thunder Ramic Ii
The polarization axis is oriented in the direction in which '2i11 is stacked. The end of this glue sintered body, Tsu J: Sintered at the same time as glue sintering (=
1. : By forming the external electrode 1 & Tsugukawa at the end where the electrode layer is exposed, an electrical connection is made with the Φ layer, and a ceramic resonator similar to that shown in Figure 11 is created. FIG. 3 shows the vibration state of the multilayer ceramic resonator thus obtained with this external connection.

In FIG. 3, the external connection electrode 14 is on the plus (+) side and the external connection electrode 15 is on the minus (-) side.
The first piezoelectric ceramic layer 11a1, the third piezoelectric ceramic layer 11c, and the fifth piezoelectric ceramic layer 1
1e extends in the thickness direction, and the second piezoelectric ceramic layer 11b and the fourth piezoelectric ceramic layer 11d have a thickness of 1
It becomes a lit C in the direction of no.

Therefore, the overall vibration of this ceramic resonator is the first
Layer piezoelectric ceramic layer 11a-C sparse→dense→sparse→
Vibration in the thickness direction, called density, will occur. Note that -I-1- in the figure does not indicate a charge.

Here, the point to pay particular attention to is the piezoelectric ceramic layer 11a.
Even if the thickness of ~lie is thin, the overall mechanical strength of b is sufficiently large for practical use. Therefore, each piezoelectric ceramic layer 11a to 11e has, for example, 10 to 10
It is said that it is possible to make the layer as thin as 0 μm.

This means that, as mentioned above, the thickness of the piezoelectric ceramic layers 11a to 11e must be reduced in order to be used in a high frequency range. By the way, if (11d(7) thickness is passed through each piezoelectric ramic layer 11a by 1oot1mh), its resonant frequency is 20M+-(bσ of /) is 111, and j When the instep is 10μm, its resonance frequency is 2
00M l-1z will be obtained.

Next, the ceramic resonator according to the present invention will be explained according to specific embodiments.

A piezoelectric material based on 1' IJ 1-i 0: containing c La 203 and 1vln 02 as subcomponents is 1.
~ Shaped by the cutter blade method to a thickness of 350
Create a μm ceramic green sheet 1. 1b sheets of this Lerami Tsuku Green Sea 1 were stacked and crimped, and cut in the stacking direction to form 11 chip-shaped laminates.
[or] this. (σ) The laminate is fired in air or in an oxygen atmosphere at 1200°C in a row 4'1 between 1211 and 1 to obtain a laminate sintered body.

Silver was deposited on the upper and lower surfaces of this laminated sintered body to form polarization electrodes, which were then immersed in insulating oil (1) at 80°C and exposed to a DC voltage of 3kV/n1nl for 30 minutes. By this process, the laminated sintered body was divided into parts 144 in one direction along the thickness direction of the stacked sheets.

A type of silver paste applied to the polarized laminated sintered body was applied and cured with heat at 120° C. to form an electrode. The ceramic resonator thus obtained had a sample size of 5 mm x 4 mm x 3 mm.

When we measured the relationship between frequency and impedance for this trial, we obtained the results shown in Figure 4. Fourth
As is clear from the figure, the ceramic resonator according to the present invention has a resonant frequency around 12M+-12 and is free of spurious at other frequencies.

Similarly to #5, as a comparative example, the relationship between frequency and impedance was similarly measured for an example in which the polarization directions of the ceramic layers faced each other, and the results shown in FIG. 5 were obtained.

The trial sample was prepared in substantially the same manner as in the above-mentioned example.

However, regarding polarization, in one culm of the above example,
Polarization is performed by the electrode layers through external connection electrodes formed on the end faces of the sintered laminate, and the polarization directions 7'j of the ramic layers are arranged to face each other.

This figure 5 shows J, which is obvious when compared with figure 4.
: In other words, there are no resonance points in the high frequency range, and there are many resonance points in the low frequency range. In the figure, 1 is a vibration corresponding to the length of the test, 2 is a vibration corresponding to the width of the test, and 3 is a vibration corresponding to the thickness of the test.

According to the ceramic resonator according to the present invention, a single electrode layer is present inside the ceramic resonator, and a plurality of piezoelectric ceramic layers are integrally sintered to form a laminated sintered body, and the piezoelectric ceramic layers are stacked in the polarization direction. Compared to the conventional ceramic J (pendulum) with 17 integrated vibrations, a ceramic pendulum with 11 J (1 frequency) can be obtained.

7j1 Conventional ceramic with thickness and vibration However, according to the present invention, the frequency of the electroceramic layer is 10 MHz.
It can be made as thin as 200M l-(
A resonance frequency of about Z can be obtained. Moreover, since it is a laminated type that is sintered as one piece, there is no problem in terms of igneous strength.

[Brief explanation of drawings]

FIG. 1 shows an embodiment of the ceramic resonator of the present invention.
FIG. 2 is a perspective view for explaining one culm for manufacturing the ceramic resonator of the present invention, FIG. 3 is a sectional view for explaining the vibration state, FIGS. 4 and 5. 11 shows the relationship between frequency and impedance, FIG. 4 shows an example of the present invention, and FIG. 5 shows a comparative example. 10 is a laminate, 11 is a piezoelectric ceramic layer, 12.13 is 11-electrode layer, 14.1! i is an electrode for external connection. 1st case Applicant Hanta Seisakusho Co., Ltd. 81F] Boundary Z Exit Diagram Procedures Amendment R? <7i type> 1. Indication of the case 1981 Patent Application No. 139 oat@2, name of the invention Ceramic Resonator 3, person making the amendment, case relationship Patent applicant address 2-26-10 Tenjin, Nagaokakyo City, Kyoto Prefecture Name (
623) Co., Ltd. [Month 1] Manufactured in 1981
January 29th (Shipping 1) 5. Number of inventions increased by amendment 1, engraving of 111m of details of amendment (no change in content)

Claims (1)

[Claims] A piezoelectric ceramic layer? ! Two or more layers are stacked together and integrally sintered to form a laminate, and a plurality of single electrode layers are formed parallel to the piezoelectric ceramic layer and extend to the ends of the laminate, and the piezoelectric ceramic The layers are polarized in the same direction as the stacked 1T direction. External connection electrodes are formed on the end faces of the laminate to be electrically connected to the ends of the electrode layers exposed on the sacral surface of the laminate. The ceramic JU pendulum is characterized by: