CN106160692B

CN106160692B - Crystal oscillator and crystal oscillator package including the same

Info

Publication number: CN106160692B
Application number: CN201510166329.XA
Authority: CN
Inventors: 李承燮; 李在祥
Original assignee: Samsung Electro Mechanics Co Ltd
Current assignee: Samsung Electro Mechanics Co Ltd
Priority date: 2014-09-23
Filing date: 2015-04-09
Publication date: 2021-04-09
Anticipated expiration: 2035-04-09
Also published as: CN106160692A; KR20160035352A; KR101616632B1

Abstract

A crystal oscillator and a crystal oscillator package including the same are provided. The crystal oscillator includes a crystal member, excitation electrodes formed on both surfaces of the crystal member, respectively, and at least one bending vibration suppression portion formed on the excitation electrodes. The plurality of bending vibration suppression portions are formed in the form of a pattern or in the form of steps, and are disposed to be spaced apart from each other by a distance equal to the wavelength distance of the bending vibration generated in the crystal member or are disposed to be non-periodically spaced apart from each other.

Description

Crystal oscillator and crystal oscillator package including the same

This application claims priority and benefit from korean patent application No. 10-2014-0126830, filed by the korean intellectual property office at 23/9/2014, the disclosure of which is incorporated herein by reference.

Technical Field

The present disclosure relates to a crystal oscillator and a crystal oscillator package including the same.

Background

In general, crystal oscillators have various applications such as frequency oscillators, frequency adjusters, and frequency converters. Such a crystal oscillator generally uses a crystal having good piezoelectric characteristics as a piezoelectric material. Here, the crystal serves as a stable mechanical vibration generator.

Such crystals are grown manually in an autoclave and cut based on the crystal axis, and the size and shape of the crystal can be tailored to provide the desired characteristics to produce the crystal in wafer form. Here, the crystal should be formed to have low phase noise, high quality (Q) value, and low frequency change rate with respect to time and environmental changes. Here, the Q value indicates a band selection characteristic in a resonator, a filter, an oscillator, or the like, and the higher the Q value, the better the frequency selection characteristic of the oscillator.

Meanwhile, the crystal oscillator has a problem that unnecessary vibration such as bending vibration may occur. In this case, the Q value may decrease and the Crystal Impedance (CI) may increase, thereby deteriorating the characteristics of the oscillator.

Disclosure of Invention

An aspect of the present disclosure may provide a crystal oscillator having improved vibration characteristics by significantly reducing bending vibration or shifting a bending vibration resonance frequency from an operating frequency range to outside the operating frequency range, and a crystal oscillator package including the crystal oscillator.

According to an aspect of the present disclosure, a crystal oscillator may include a crystal member, excitation electrodes formed on both surfaces of the crystal member, respectively, and at least one bending vibration suppression portion formed on the excitation electrodes.

The bending vibration suppressing portion may be provided as a plurality of bending vibration suppressing portions that are provided so as to be spaced apart from each other by a distance equal to a wavelength distance of the bending vibration generated in the crystal member.

According to another aspect of the present disclosure, a crystal oscillator may include a crystal member, an excitation electrode formed on the crystal member, and a bending vibration suppression portion formed on the excitation electrode spaced apart from each other by a predetermined distance.

According to another aspect of the present disclosure, a crystal oscillator may include a crystal member and excitation electrodes respectively formed on both surfaces of the crystal member, at least a portion of the excitation electrodes having a thickness different from that of other portions due to a step.

According to another aspect of the present disclosure, a crystal oscillator package may include: a base substrate; a crystal member having excitation electrodes formed on both surfaces thereof, respectively, and one side of which is bonded to the base substrate; at least one bending vibration suppression portion formed on the excitation electrode; a support part formed on an edge of the base substrate; and a cover disposed on the support part to seal a space in which the crystal member is accommodated.

The bending vibration suppressing portions may be disposed to be spaced apart from each other by a distance equal to a wavelength distance of the bending vibration generated in the crystal member.

Drawings

The above and other aspects, features and other advantages of the present disclosure will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, in which:

fig. 1 is a side cross-sectional view of a crystal oscillator package according to an exemplary embodiment of the present disclosure;

FIG. 2 is a plan view taken along line A-A' in FIG. 1;

fig. 3 and 4 are sectional views for describing flexural vibration of the crystal oscillator shown in fig. 2;

FIG. 5 is a side cross-sectional view of a crystal oscillator according to another exemplary embodiment of the present disclosure;

FIG. 6 is a plan view of FIG. 5;

FIG. 7 is a side cross-sectional view of a crystal oscillator according to another exemplary embodiment of the present disclosure;

FIG. 8 is a plan view of FIG. 7;

FIG. 9 is a side cross-sectional view of a crystal oscillator according to another exemplary embodiment of the present disclosure;

FIG. 10 is a plan view of FIG. 9;

FIG. 11 is a side cross-sectional view of a crystal oscillator according to another exemplary embodiment of the present disclosure;

FIG. 12 is a plan view of FIG. 11;

FIG. 13 is a side cross-sectional view of a crystal oscillator according to another exemplary embodiment of the present disclosure;

FIG. 14 is a plan view of FIG. 13;

fig. 15 to 17 are plan views of a crystal oscillator according to another exemplary embodiment of the present disclosure; and

fig. 18 is a side sectional view schematically showing a crystal oscillator according to the related art.

Detailed Description

Exemplary embodiments of the present disclosure will now be described in detail with reference to the accompanying drawings.

This disclosure may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.

In the drawings, the shapes and sizes of elements may be exaggerated for clarity, and the same reference numerals will be used throughout to designate the same or similar elements.

Fig. 1 is a side cross-sectional view of a crystal oscillator package showing a mesa shaped crystal oscillator cross-sectional view taken along a length direction of the mesa shaped crystal oscillator using a rectangular AT cut crystal substrate according to an exemplary embodiment of the present disclosure. In addition, fig. 2 is a plan view taken along line a-a' of fig. 1.

Referring to fig. 1 and 2, a crystal oscillator package according to an exemplary embodiment of the present disclosure may include: a base substrate 26 a; a first electrode pad 24a and a second electrode pad 24b formed on an upper surface of the base substrate 26 a; a crystal member 21 having one side fixedly mounted on the first and

second electrode pads

24a and 24b and having

excitation electrodes

22a and 22b formed on upper and lower surfaces thereof, respectively, to vibrate the crystal member 21 by an electrical signal, the

excitation electrodes

22a and 22b being electrically connected to the first and

second electrode pads

24a and 24 b; a support portion 26b formed on an edge of the base substrate 26a and forming an inner space in which the crystal member 21 is accommodated; and a cover 27 disposed on the support portion 26b to seal the inner space.

The base substrate 26a may form the bottom of the crystal oscillator package 100, and the base substrate 26a may be formed of an insulating ceramic material. For example, a sintered body (e.g., alumina or the like) formed by molding, stacking, and then sintering ceramic green sheets may be used as the base substrate 26 a.

The first and

second electrode pads

24a and 24b may be formed at one side on the upper surface of the base substrate 26 a. In addition, the supporting portion 26b may be formed along the edge of the base substrate 26 a.

The base substrate 26a may include a plurality of

external electrode pads

24c and 24d formed on a lower surface thereof to receive an electrical signal from the outside, wherein one of the plurality of

external electrode pads

24c and 24d may be electrically connected to the first electrode pad 24a and the other of the plurality of

external electrode pads

24c and 24d may be electrically connected to the second electrode pad 24 b.

The first and

second electrode pads

24a and 24b and the

outer electrode pads

24c and 24d may be connected to each other through conductive vias (not shown) formed in the base substrate 26 a. In addition, some of the plurality of

external electrode pads

24c and 24d may be used as ground electrodes.

The first and

second electrode pads

24a and 24b may be electrically connected to the

excitation electrodes

22a and 22b formed on the upper and lower surfaces of the crystal member 21, respectively, and thus may be used as paths for supplying electrical signals to the crystal member 21. A piezoelectric effect can be generated in the crystal member 21 by the above-described electric signal.

The first and

second electrode pads

24a and 24b may be formed of, for example, a conductive metal of at least one selected from the group consisting of gold (Au), silver (Ag), tungsten (W), copper (Cu), and molybdenum (Mo).

The support portion 26b may be formed along an edge of the base substrate 26a, and the support portion 26b may form an inner space in which the crystal oscillator according to the present exemplary embodiment is to be accommodated together with the base substrate 26 a.

The support portion 26b may be formed of an insulating ceramic material of the same material as that of the base substrate 26a or a conductive metal alloy of the same material as that of the cover 27.

The crystal member 21 can be manufactured by cutting and processing a crystal wafer using a photolithography technique or the like, wherein the crystal member 21 is a piezoelectric substrate ground at a predetermined thickness according to a vibration frequency or the like.

The crystal member 21 may have a substantially rectangular shape, and may be formed in a mesa shape including therein a vibrating portion 21a provided at a central portion thereof and an outer edge portion 21b provided at an edge portion of the vibrating portion 21a and formed in a thickness thinner than that of the vibrating portion 21 a.

The crystal member 21 according to the present exemplary embodiment may be cut in AT-cut so that the thickness slip vibration is excited as the main vibration.

Since the frequency variation according to the temperature variation in the vicinity of room temperature is small, the AT-cut crystal piece has been widely used as a crystal oscillator having thickness sliding vibration as the main vibration.

It is known that when a crystal member (or a piezoelectric vibrating piece) in a thickness shear vibration mode is formed such that its thickness becomes gradually thinner from the middle portion thereof toward the end portion thereof, the damping amount of vibration displacement at the end portion is increased, thereby improving the effect of trapping vibration energy in the middle portion of the piezoelectric vibrating piece and improving frequency characteristics such as CI value and Q value.

Therefore, even if the thickness of the piezoelectric vibrating piece is increased to reduce the frequency, the oscillation can be efficiently performed with small energy. In contrast, even at a relatively high frequency, the size of the piezoelectric vibrating piece can be smaller than that of a general piezoelectric vibrating piece, so that the piezoelectric vibrating piece can be minimized.

Examples of the shape of the piezoelectric vibrating piece that can achieve the vibration energy trapping effect may include: the convex curved surface is formed in a convex shape of the main surface, a space between the flat and thick middle portion and the edge of the end portion is formed in a slant surface shape of a slant surface, a thin mesa surface shape formed around a portion of the flat and thick middle portion, and the like. The crystal member 21 according to the present exemplary embodiment may have a mesa shape among the above-described shapes. However, the configuration of the present disclosure is not limited thereto.

The mesa-shaped crystal member 21 may be more advantageous than a convex-shaped crystal member or a slant-shaped crystal member because the mesa-shaped crystal member 21 may be simply processed by wet etching using a photolithography technique and may have a small deviation so as to be suitable for mass production. However, since the mesa-shaped crystal member 21 has a step between the thick middle portion and the thin outer edge portion 21b, it has a disadvantage of generating unnecessary vibrations such as bending vibrations superimposed on the main vibration in the thickness-shear vibration mode.

For this reason, the crystal oscillator according to the exemplary embodiment of the present disclosure may include a bending vibration suppression portion 25 (which will be described below).

Since the crystal member 21 according to the present exemplary embodiment is formed in a mesa shape, the crystal member 21 may include the thick portion 21a (i.e., the vibrating portion), the outer edge portion 21b, and the

excitation electrodes

22a and 22 b.

The vibrating portion 21a may be provided in the middle of the crystal member 21 and formed in a thickness thicker than that of the outer edge portion 21 b. Accordingly, the outer edge portion 21b may be formed at the periphery of the vibration portion 21a and at a relatively thinner thickness than that of the vibration portion 21 a.

The crystal member 21 may have

excitation electrodes

22a and 22b formed on the upper and lower surfaces, respectively. In addition, the crystal member may have

connection electrodes

22c and 22d formed at one side thereof, wherein the

connection electrodes

22c and 22d are connected to the

excitation electrodes

22a and 22 b.

The

excitation electrodes

22a and 22b may apply an electrical signal to the crystal member 21 to vibrate the crystal member. For this, the

excitation electrodes

22a and 22b may be formed in the same shape on both surfaces of the crystal member 21, respectively.

In the present exemplary embodiment, the

excitation electrodes

22a and 22b may be formed throughout the vibrating portion 21a of the crystal member 21. However, the configuration of the present disclosure is not limited thereto, but various modifications may be made. For example, the

excitation electrodes

22a and 22b may be formed in a size smaller than that of the vibration part 21a, if necessary.

One side of the

connection electrodes

22c and 22d may be connected to the

excitation electrodes

22a and 22b, and the other side may be electrically connected to the first and

second electrode pads

24a and 24b through the conductive adhesive 23.

The

respective connection electrodes

22c and 22d may be formed on both surfaces of one side of the crystal member 21, respectively. In this case, since both surfaces of the crystal member 21 can be formed in the same shape, it is possible to bond it to the base substrate 26a without distinguishing both surfaces of the crystal member 21 from each other.

The

excitation electrodes

22a and 22b and the

connection electrodes

22c and 22d may be formed of a metal plating layer, wherein the metal plating layer may be formed by performing a method such as a sputtering method or a deposition method on a material such as chromium, nickel, gold, or silver. However, the present disclosure is not limited thereto.

One side of the crystal member 21 as described above may be fixed within the internal space formed by the base substrate 26a and the support portion 26 b. In detail, the crystal member 21 may be bonded to the base substrate 26a by the conductive adhesive 23, so that the first and

second electrode pads

24a and 24b formed on the base substrate 26a and the

excitation electrodes

22a and 22b formed on the upper and lower surfaces of the crystal member 21, respectively, may be electrically connected to each other, respectively.

Here, the

excitation electrodes

22a and 22b may be electrically connected to the first and

second electrode pads

24a and 24b through the

connection electrodes

22c and 22d described above.

The cover 27 may be provided in a form of being seated on an upper end of the support portion 26b to seal an inner space in which the crystal member 21 is mounted, thereby completing the inner space, and the cover 27 may be fixed and joined to the support portion 26b by a conductive adhesive (not shown) or the like.

Since the operating efficiency and quality of the crystal oscillator are significantly affected by the external environment and contaminants, etc., it is necessary to seal the crystal oscillator package 100 so that the leak rate thereof is very low to protect the crystal member 21 from the external environment and contaminants of the crystal oscillator package 100.

For this reason, the inside of the crystal oscillator package 100 may be hermetically sealed by the cover 27. In addition, the internal space of the crystal oscillator package 100 may be sealed by an inert gas such as nitrogen, helium, argon, or the like, or a vacuum state.

In addition, the crystal oscillator according to the present exemplary embodiment may have at least one bending vibration suppression portion 25.

Fig. 18 is a side sectional view schematically showing a crystal oscillator according to the related art. Referring to fig. 18, in the crystal oscillator according to the related art, as described above, parasitic vibration (unnecessary vibration) such as bending vibration P or the like is generated. In this case, since energy is consumed by the bending vibration, the Q value decreases, the Crystal Impedance (CI) increases, and the characteristics of the oscillator deteriorate.

Therefore, in the crystal oscillator according to the present exemplary embodiment, the flexural vibration suppression section 25 may be used to suppress generation of the flexural vibration P (see fig. 18) in the crystal oscillator, or may be used as a dynamic vibration absorber that converts the resonance frequency in the flexural vibration mode to another frequency.

The bending vibration suppression portion 25 according to the present exemplary embodiment may be formed on the

excitation electrodes

22a and 22b formed on the crystal member 21. In more detail, the bending vibration suppression section 25 may be formed in the form of a reinforcing pattern protruding from the

excitation electrodes

22a and 22b to the outside, or may be formed substantially in the form of a lattice pattern by engraving the

excitation electrodes

22a and 22 b.

However, the bending vibration suppressing portion 25 according to the present exemplary embodiment is not limited to being formed in the form of a reinforcing pattern, and various modifications may be made.

For example, the bending vibration suppressing portion 25 may be formed in a stepped form in one step. In detail, the bending vibration suppression portion 25 may be defined as a step where the thickness of the

excitation electrodes

22a and 22b becomes thick or thin. Meanwhile, the bending vibration suppression portion 25 may be defined in the form of a pattern: the rigidity of the crystal oscillator changes sharply with a step change in the thickness of the crystal oscillator itself.

Fig. 3 and 4 are sectional views for describing flexural vibration of the crystal oscillator shown in fig. 2, wherein fig. 3 shows a sectional view taken along line B-B' of fig. 2; fig. 4 shows a cross-sectional view taken along line C-C' of fig. 2.

The bending vibration suppressing portion 25 according to the present exemplary embodiment may be mounted in the form of a pattern located at the maximum displacement point of the parasitic bending vibration. The distance D between the patterns of the bending vibration suppression portions 25 may have the following relationship.

(expression 1)

D ═ λ × m (m ═ 1, 2, 3, … … n, integer)

Here, D denotes a distance between patterns of the bending vibration suppression portion 25 formed on one

excitation electrode

22a or 22b, and λ denotes a wavelength of the bending vibration P (see fig. 18, unnecessary vibration) generated in the crystal member 21.

Referring to expression 1, the distance D between the bending vibration suppression portions may be set to an integral multiple of λ. For example, D may be set to be one time λ, i.e., the distance is equal to λ.

Meanwhile, in the case where the maximum displacement point of the flexural vibration is not set at a position corresponding to an integral multiple of λ due to the nonlinear characteristic of the crystal vibrator, the distance D may be defined as a real number that is not constant. In addition, in the case where the number of unnecessary bending vibration modes is one or more, the number of distances D between the patterns of the bending vibration suppression portions may be one or more.

In addition, for example, the bending vibration suppression portion 25 may be formed along the wavelength λ (maximum displacement point) of the bending vibration P. That is, in the crystal oscillator according to the present exemplary embodiment, the bending vibration suppression portion 25 can be designed and manufactured on the

excitation electrodes

22a and 22b in the maximum point of the maximum amplitude of the parasitic bending vibration.

The bending vibration suppression portion 25 may function as a mass body or a rigid body that cancels the bending vibration P (see fig. 18). Therefore, when the bending vibration P is generated in the crystal member 21, the bending vibration suppression portion 25 formed at the wavelength distance of the bending vibration P can serve as a resistance to the bending vibration P.

Therefore, as shown in fig. 3, the bending vibration suppression portion 25 may reduce the magnitude of the bending vibration P1, or vary the frequency of the bending vibration to suppress the generation of the bending vibration.

As a result, the crystal resistance (CI) can be reduced.

As described above, in the crystal oscillator according to the present exemplary embodiment, since the loss of energy caused by bending vibration generated in a certain operating frequency is significantly reduced and energy can be transferred only in a desired thickness sliding vibration mode, the overall vibration efficiency can be improved.

Meanwhile, the bending vibration suppression section 25 can be realized by forming the

excitation electrodes

22a and 22b thick locally in the process of forming the

excitation electrodes

22a and 22b on the crystal member 21. For example, the bending vibration suppression portion 25 may be formed by: forming

excitation electrodes

22a and 22b on the crystal member 21; a mask having a partially opened portion corresponding to the bending vibration suppression portion 25; the process of forming the

excitation electrodes

22a and 22b is performed.

In this case, since the bending vibration suppression portion 25 is formed of the same material as that of the

excitation electrodes

22a and 22b, the bending vibration suppression portion 25 may be formed integrally with the

excitation electrodes

22a and 22 b. Therefore, the bending vibration suppression portion 25 may be formed in such a manner that the

excitation electrodes

22a and 22b partially protrude.

In another case, the bending vibration suppression portion 25 may be formed of a material different from that of the

excitation electrodes

22a and 22 b. In this case, the bending vibration suppression portion 25 may be bonded to the interface of the

excitation electrodes

22a and 22b by chemical bonding or physical bonding.

In addition, the height (thickness) and length of the bending vibration suppression portion 25 may be set in various forms depending on the form of the bending vibration.

The pattern width and thickness of the bending vibration suppression portion 25 can be adjusted up to several micrometers using a micro-mechanical technique. Therefore, since the bending vibration suppression portion 25 can be provided at the position of the maximum displacement of the bending vibration P (see fig. 18), the bending vibration suppression portion 25 can suppress the bending vibration very effectively.

Meanwhile, the configuration of the present disclosure is not limited to the above-described exemplary embodiments.

The crystal oscillator according to the following exemplary embodiment may be similar to the crystal oscillator according to the above-described exemplary embodiment except for the shape of the bending vibration suppression portion 25. Therefore, detailed description of components similar to those of the crystal oscillator according to the above-described exemplary embodiment will be omitted, and the bending vibration suppressing portion 25 different from the bending vibration suppressing portion 25 of the crystal oscillator according to the above-described exemplary embodiment will be mainly described.

FIG. 5 is a side cross-sectional view of a crystal oscillator according to another exemplary embodiment of the present disclosure; fig. 6 is a plan view of fig. 5. Here, fig. 5 shows a sectional view taken along line B-B' of fig. 6.

Referring to fig. 5 and 6, in the crystal oscillator according to the present exemplary embodiment, the bending vibration suppressing portions 25 do not protrude in a lattice form, but protrude in a dot form, and the bending vibration suppressing portions 25 having the dot form may substantially form a lattice pattern. Here, similar to the above-described exemplary embodiment, the internal distance D of the lattice pattern may be equal to the wavelength λ of the bending vibration P (see fig. 18).

In addition, in the crystal oscillator according to the present exemplary embodiment, the excitation electrode 22a and the bending vibration suppression portion 25 of the crystal member 21 may be formed of different materials.

For example, the excitation electrode 22a may be formed of a metal plating layer made of chromium, nickel, gold, silver, copper, or the like, and the bending vibration suppression portion 25 may be formed of a metal different from the metal of the excitation electrode 22 a.

However, the present disclosure is not limited thereto, but various modifications may be made. For example, the bending vibration suppression portion 25 may be formed of a solder resist, a resin material such as an epoxy resin, or a ceramic material or the like.

In addition, such a configuration can also be easily applied to the above-described exemplary embodiments.

FIG. 7 is a side cross-sectional view of a crystal oscillator according to another exemplary embodiment of the present disclosure; fig. 8 is a plan view of fig. 7. Here, fig. 7 shows a sectional view taken along line B-B' of fig. 8.

Referring to fig. 7 and 8, in the crystal oscillator according to the present exemplary embodiment, the bending vibration suppression section 25 does not protrude in a lattice form, but in a straight line form. Here, the patterns of the bending vibration suppression portions 25 may be disposed in parallel to each other in a state of being spaced apart from each other by a predetermined distance D in the form of stripes, and the distance D between the patterns of the bending vibration suppression portions 25 may be equal to the wavelength λ of the bending vibration P (see fig. 18), similar to the above-described exemplary embodiment.

FIG. 9 is a side cross-sectional view of a crystal oscillator according to another exemplary embodiment of the present disclosure; fig. 10 is a plan view of fig. 9. Here, fig. 9 shows a sectional view taken along line B-B' of fig. 10.

Referring to fig. 9 and 10, in the crystal oscillator according to the present exemplary embodiment, the bending vibration suppression section 25 may be formed in the form of a broken-line lattice.

Here, the pattern of the bending vibration suppressing portions 25 does not protrude in a lattice form but protrudes in a broken line form, the bending vibration suppressing portions 25 having the broken line form may substantially form a lattice pattern, and the distance D between the patterns of the bending vibration suppressing portions 25 may be equal to the wavelength λ of the bending vibration P (see fig. 18), similar to the above-described exemplary embodiment.

FIG. 11 is a side cross-sectional view of a crystal oscillator according to another exemplary embodiment of the present disclosure; fig. 12 is a plan view of fig. 11. Here, fig. 11 shows a sectional view taken along line B-B' of fig. 12.

In addition, fig. 13 is a side cross-sectional view of a crystal oscillator according to another exemplary embodiment of the present disclosure; fig. 14 is a plan view of fig. 13. Here, fig. 13 shows a sectional view taken along line B-B' of fig. 14.

Referring to fig. 11 to 14, in the crystal oscillator, the bending vibration suppression portion 25 may be formed in a broken line form. The bending vibration suppressing portion 25 shown in fig. 11 and the bending vibration suppressing portion 25 shown in fig. 13 may be different from each other only in the direction of the line (pattern).

The patterns of the bending vibration suppression portions 25 may be disposed in parallel with each other in a state of being spaced apart from each other by a predetermined distance D, and the distance D between the patterns of the bending vibration suppression portions 25 may be the same as the wavelength λ of the bending vibration P (see fig. 18), similar to the above-described exemplary embodiment.

Fig. 15 to 17 are plan views of a crystal oscillator according to another exemplary embodiment of the present disclosure.

Fig. 15 to 17 show a case where the pattern of the bending vibration suppression portion 25 is formed in the form of an oblique line inclined from the outline of the crystal member 21.

In more detail, fig. 15 shows an example in which the bending vibration suppressing portions 25 shown in fig. 2 are provided in the form of oblique lines, and fig. 16 shows an example in which the bending vibration suppressing portions 25 shown in fig. 6 are provided in the form of oblique lines. In addition, fig. 17 shows an example in which the bending vibration suppression portions 25 shown in fig. 12 are provided in the form of oblique lines.

As set forth above, with the crystal oscillator and the crystal oscillator package including the same according to the exemplary embodiments of the present disclosure, since the coupling between the thickness sliding vibration and the bending vibration can be prevented by the bending vibration suppression portion, the vibration loss can be reduced.

In addition, since the vibration loss is reduced, a crystal oscillator having a high Q value and a low CI can be provided. Therefore, low vibration loss and stable frequency characteristics can be obtained.

While exemplary embodiments have been shown and described above, it will be apparent to those skilled in the art that modifications and variations can be made without departing from the scope of the invention defined by the claims.

Claims

1. A crystal oscillator, comprising:

a crystal member;

excitation electrodes formed respectively over both surfaces of the vibrating portion of the crystal member; and

at least one bending vibration suppressing portion formed on the excitation electrode in a pattern form or a step form, wherein,

the bending vibration suppression portion is provided as a plurality of bending vibration suppression portions that are provided so as to be spaced apart from each other by a distance equal to a wavelength distance of one or more bending vibrations generated in the crystal member, or are provided so as to be spaced apart from each other by a plurality of distances equal to a plurality of different wavelength distances of the plurality of bending vibrations generated in the crystal member.

2. The crystal oscillator according to claim 1, wherein the bending vibration suppression section protrudes in a lattice form from the excitation electrode or is formed in a lattice shape by engraving the excitation electrode.

3. The crystal oscillator according to claim 1, wherein the bending vibration suppression section protrudes from the excitation electrode periodically or non-periodically in the form of a plurality of dots.

4. The crystal oscillator according to claim 3, wherein the bending vibration suppression portions formed in the form of a plurality of dots are provided to form a lattice pattern.

5. The crystal oscillator according to claim 1, wherein the bending vibration suppression portions are formed by patterns having a form of stripes, and are periodically or non-periodically disposed to be spaced apart from each other.

6. The crystal oscillator according to claim 1, wherein the bending vibration suppression portion is formed of the same material as that of the excitation electrode.

7. The crystal oscillator according to claim 1, wherein the bending vibration suppression portion is formed of a material different from a material of the excitation electrode.

8. The crystal oscillator according to claim 1, wherein the crystal member has thickness sliding vibration as main vibration, and a thickness of a central portion of the crystal member is thicker than a thickness of an outer peripheral region of the crystal member.

9. A crystal oscillator, comprising:

a crystal member;

bending vibration suppression portions spaced apart from each other by a predetermined distance and formed on the excitation electrode in the form of a pattern or a step, wherein,

the bending vibration suppression portions are provided to be spaced apart from each other by a distance equal to a wavelength distance of one or more bending vibrations generated in the crystal member, or are provided to be spaced apart from each other by a plurality of distances equal to a plurality of different wavelength distances of a plurality of bending vibrations generated in the crystal member.

10. The crystal oscillator according to claim 9, wherein the bending vibration suppression section is provided at a point corresponding to a wavelength of the bending vibration generated in the crystal member, wherein the point corresponds to a maximum displacement point of the bending vibration.

11. The crystal oscillator according to claim 9, wherein the bending vibration suppression portion is formed by partially protruding the excitation electrode.

12. A crystal oscillator, comprising:

a crystal member; and

excitation electrodes respectively formed over both surfaces of the vibrating portion of the crystal member, at least a portion of the excitation electrodes having a thickness different from that of other portions due to the step, wherein,

the steps are disposed to be spaced apart from each other by a distance equal to a wavelength distance of one or more bending vibrations generated in the crystal member, or disposed to be spaced apart from each other by a plurality of distances equal to a plurality of different wavelength distances of a plurality of bending vibrations generated in the crystal member.

13. A crystal oscillator package comprising:

a base substrate;

a crystal member having excitation electrodes formed respectively throughout both surfaces of a vibration portion of the crystal member, and one side of the crystal member being bonded to a base substrate;

at least one bending vibration suppression portion formed on the excitation electrode in a pattern form or a step form;

a support part formed on an edge of the base substrate; and

a cover provided on the support part to seal a space in which the crystal member is accommodated,

14. The crystal oscillator package according to claim 13, wherein the bending vibration suppression portion is provided at a point corresponding to a wavelength of the bending vibration generated in the crystal member, wherein the point corresponds to a maximum displacement point of the bending vibration.

15. The crystal oscillator package of claim 13, wherein the plurality of bending vibration suppression portions are disposed to be non-periodically spaced apart from each other.