JPH04102316U - Piezoelectric resonant components - Google Patents

Abstract

(57) [Summary] [Purpose] To eliminate the need to form an extraction electrode for a common electrode on a piezoelectric substrate, and to realize miniaturization of piezoelectric resonant components. [Structure] A pair of opposing electrodes 2 on one side of a piezoelectric substrate 1
A piezoelectric element 5 formed by providing a vibrating electrode part 3 consisting of a and 2b and a common electrode 4 facing the vibrating electrode part 3 on the other surface is sandwiched between sealing substrates 7a and 7b. A common electrode extraction electrode 8 is formed on the opposite sealing substrate, and the common electrode 4 is connected to the common electrode extraction electrode 8 on the sealing substrate via a conductive elastic body 9.

Description

[Detailed explanation of the idea]

0001

[Industrial application field]

The present invention is characterized by a piezoelectric resonant component, specifically, a common electrode lead-out structure. , relating to piezoelectric resonant components compatible with miniaturization.

0002

[Conventional technology]

In conventional piezoelectric resonant components that utilize thickness-shear vibration mode, for example, 7. As shown in FIG. 8, a pair of opposing electrodes 22a, 2 are provided on one surface of the piezoelectric substrate 21. A vibrating electrode part 23 consisting of 2b is formed, and a vibrating electrode part 23 is formed on the other side of the vibration electrode part 23. By providing the common electrode 24 at the position shown in FIG. A piezoelectric element 25 is formed. Then, the common electrode 24 of the piezoelectric element 25 is formed. A lead electrode 26 drawn out from the common electrode 24 is formed on the flat surface. this The extraction electrode 26 is connected to the opposing electrodes 22a and 22b (i.e., the vibration electrodes) formed on the other surface. When formed at a position facing (overlapping) an electrode such as the dynamic electrode part 23), a voltage is applied. When applied, vibration occurs in the opposing portion and deteriorates the resonance characteristics of the piezoelectric element 25. It turns out. Therefore, the opposing electrodes 22a, 22b (vibrating electrode portion 23) or Select a position that does not face the drawn-out electrodes 27a, 27b, etc. drawn out from the The electrodes 26 are arranged in a routed manner. (Figure 8).

0003

[Problem that the idea aims to solve]

In this way, the conventional piezoelectric resonant component described above has the common electrode 24 connected to the other side of the piezoelectric substrate 21. In order to arrange it in a position that does not face the vibrating electrode part 23 on the surface of Therefore, there is a problem that the piezoelectric element 25 becomes larger. and , since the sealing substrate that seals the piezoelectric element 25 from both sides also becomes larger, The problem is that it is difficult to miniaturize the final product, the piezoelectric resonant component. are doing.

0004 This idea solves the above problems, and includes a common electrode drawer on the piezoelectric substrate. Our aim is to provide a piezoelectric resonant component that does not require the formation of electrodes and can be miniaturized. target

[0005]

[Means to solve the problem]

In order to solve the above purpose, the piezoelectric resonant component of this invention has one side of the piezoelectric substrate. A vibrating electrode part is provided on the surface, and a common electrode facing the vibrating electrode part is provided on the other surface. In a piezoelectric resonant component formed by sandwiching a piezoelectric element between sealed substrates, the common electrode and A common electrode lead electrode is formed on the sealing substrate on the opposite side, and the common electrode The electrode is connected to the common electrode extraction electrode via a conductive elastic body. Ru.

[0006]

[Effect]

The common electrode of the piezoelectric element is connected to a common electrode formed on the sealing substrate via a conductive elastic material. Since it is connected to the pole extraction electrode, the piezoelectric element (the surface on which the common electrode is formed) , there is no need to form an extraction electrode for the common electrode, and there is no need to secure space for it. This makes it possible to reduce the size of the piezoelectric element, which in turn makes it possible to reduce the size of the piezoelectric resonator. The entire structure can be downsized. Conductive elastic bodies can also be used as damping materials. It also contributes to improving piezoelectric properties.

[0007]

【Example】

Hereinafter, an embodiment of this invention will be described based on the drawings. Figures 1 and 2 show the results of this invention. FIG. 2 is a diagram showing the front and back surfaces of a piezoelectric element used in a piezoelectric resonant component of an example. 3 to 6 are diagrams showing the manufacturing process of the piezoelectric resonant component of this example, respectively. . As shown in FIGS. 1 and 2, the piezoelectric element 5 of the piezoelectric resonant component of this embodiment is based on a piezoelectric base. A vibrating electrode section 3 consisting of a pair of opposing electrodes 2a and 2b and a counter electrode are provided on one surface of the plate 1. Extracting electrodes 12a and 12b are provided that are electrically connected to the poles 2a and 2b, and the above-mentioned vibration on the other surface is It is formed by providing a common electrode 4 at a position opposite to the electrode part 3, as shown in the figure. It has an equivalent circuit as shown in 9.

[0008] Next, a process for manufacturing a piezoelectric resonant component using the piezoelectric element 5 configured as described above will be described. explain about. First, the piezoelectric element 5 is sandwiched between the sealing substrates 7a and 7b from both sides. (Figure 3). An electrode (common electrode) is provided on the surface of the lower sealing substrate 7b facing the common electrode 4. A lead-out electrode (for conducting electrode) 8 is formed. This electrode 8 is a piezoelectric member of the sealing substrate 7b. It is formed from the surface facing the element 5 to its side surfaces (in some cases, it is sealed). (It may be formed all the way to the bottom surface of the stop substrate 7b). And as shown in Figure 4 , for the lower surface of the piezoelectric element 5 (the surface on which the common electrode 4 is formed) and the common electrode of the sealing substrate 7b. For example, between the extraction electrode 8 and the elastic material such as silicone rubber, metal powder or the like is used. A conductive elastic body 9 made of a mixture of conductive particles is filled with the conductive elastic body 9. The common electrode 4 and the common electrode extraction electrode 8 are electrically connected by the body 9 . This guidance The electro-elastic body 9 holds the piezoelectric element 5 together before sandwiching the piezoelectric element 5 between the sealing substrates 7a and 7b. It may be applied to the conductive electrode 4 or the common electrode extraction electrode 8 on the sealing substrate 7b, Further, after being sandwiched between the sealing substrates 7a and 7b, a shape is formed between the piezoelectric element 5 and the sealing substrate 7b. It is also possible to fill the created space (vibration space). Then, the sealing substrate 7 After sealing both ends of the element held by a and 7b with sealing plates 10a and 10b (Fig. 5) , the leads extending from the counter electrodes 2a, 2b and exposed from the ends of the sealing substrates 7a, 7b. The external electrodes 11a and 11b that are electrically connected to the output electrodes 12a and 12b are connected to the sealing plate 10a. , 10b are formed on both ends where the external electrodes 11a, 10b are not attached. A center electrode 11c is formed between the electrodes 11b. Note that the center electrode 11c is a sealing group. Connects to the common electrode extraction electrode 8 drawn out from the sides of the plates 7a and 7b to the bottom. It continues.

[0009] In the piezoelectric resonant component configured as described above, the common electrode 4 of the piezoelectric element 5 is , a common electrode extraction electrode 8 formed on the sealing substrate 7b via a conductive elastic body 9 Since the piezoelectric element 5 (the surface on which the common electrode is formed) has a common electrode It is no longer necessary to secure space for the extraction electrode, and the piezoelectric element can be made smaller. Since the piezoelectric resonant component is molded, the entire piezoelectric resonant component can be miniaturized. In addition, conductive elastic Since the elastic body 9 also functions as a damping material, it can also improve the characteristics of piezoelectric resonant components. At the same time, it eliminates the need to apply a separate damping material to the vibrating part of the piezoelectric element. As a result, manufacturing costs can be reduced.

0010 In the above embodiment, a conductive elastic material is used throughout the space between the piezoelectric element 5 and the sealing substrate 7b. 9 was explained, but it is also possible to partially apply (fill) the conductive elastic material. It may be configured so that Further, in the above embodiment, only one vibrating electrode portion is formed. We have explained piezoelectric resonant components using piezoelectric elements, but the multi-stage vibrating electrode section This also applies to piezoelectric resonant components that use formed piezoelectric elements (with multiple common electrodes). Can apply ideas.

[0011] Furthermore, when using a piezoelectric element with common electrodes formed on both sides, It is also possible to apply a conductive elastic material to both sides of the piezoelectric element. .

0012

[Effect of the idea]

As mentioned above, the piezoelectric resonant component of this invention has a common electrode formed on the piezoelectric element. A common electrode lead electrode is formed on the sealing substrate on the side opposite to the common electrode. is configured to be connected to the common electrode extraction electrode via a conductive elastic body. Therefore, in order to form a common electrode lead electrode on the surface of the piezoelectric element where the common electrode is formed, No additional space is required. Therefore, a piezoelectric element and a sealing substrate for sealing it This makes it possible to reduce the size of the piezoelectric resonant component as a whole. be able to.

[0013] In addition, the conductive elastic material also functions as a damping material, improving piezoelectric properties. It also eliminates the need to apply a separate damping material to the vibrating part of the piezoelectric element. This can simplify the manufacturing process and improve productivity.

[Brief explanation of drawings]

FIG. 1 is a plan view showing one surface of a piezoelectric element used in a piezoelectric resonant component according to an embodiment of the invention.

FIG. 2 is a plan view showing the other side of the piezoelectric element used in the piezoelectric resonant component of the embodiment of the invention.

FIG. 3 is an exploded perspective view showing a manufacturing process of a piezoelectric resonant component according to an embodiment of the invention.

FIG. 4 is a perspective view showing a manufacturing process of a piezoelectric resonant component according to an embodiment of the invention.

FIG. 5 is a perspective view showing a manufacturing process of a piezoelectric resonant component according to an embodiment of the invention.

FIG. 6 is a perspective view showing a piezoelectric resonant component according to an embodiment of the invention.

FIG. 7 is a plan view showing one surface of a piezoelectric element used in a conventional piezoelectric resonant component.

FIG. 8 is a plan view showing the other side of a piezoelectric element used in a conventional piezoelectric resonant component.

FIG. 9 is a diagram showing an equivalent circuit of a piezoelectric element used in the piezoelectric component of this invention and a conventional example.

[Explanation of symbols]

1 Piezoelectric substrate 2a, 2b counter electrode 3 Vibrating electrode section 4 Common electrode 5 Piezoelectric element 7a, 7b sealing substrate 8 Common electrode extraction electrode 9 Conductive elastic body

Claims (1)

[Scope of utility model registration request] 1. A piezoelectric resonant component comprising a piezoelectric element formed by providing a vibrating electrode portion on one surface of a piezoelectric substrate and a common electrode facing the vibrating electrode portion on the other surface, sandwiched between sealing substrates. A piezoelectric device characterized in that a common electrode lead electrode is formed on the sealing substrate on the side facing the common electrode, and the common electrode is connected to the common electrode lead electrode via a conductive elastic body. Resonant parts.