JP2021005897A - Vibration device, electronic apparatus and mobile body - Google Patents

Abstract

To provide a vibration device in which the temperature difference between the temperature of a vibration piece and the temperature detected by a temperature-sensitive element can be reduced.SOLUTION: A crystal oscillator 1 includes: a crystal vibration piece 10; a thermistor 20; and a package base 31 having a first principal surface 33 and a second principal surface 34 in the relationship of front and back with each other. The crystal vibration piece 10 is mounted on the first principal surface 33 side of the package base 31, and the thermistor 20 is housed in a recess 35 provided in the second principal surface 34 side of the package base 31. On the second principal surface 34 of the package base 31, a plurality of electrode terminals 37a-37d connected with the crystal vibration piece 10 or the thermistor 20 are provided, and the distance L1 from the mounting surface of the electrode terminals 37a-37d to the thermistor 20, in a first direction perpendicular to the first principal surface 33, is 0.05 mm or more.SELECTED DRAWING: Figure 1

Description

The present invention relates to a vibrating device, an electronic device including the vibrating device, and a mobile body.

Conventionally, as an example of a vibration device, a piezoelectric vibration element, a temperature-sensitive component, a first accommodating portion for accommodating the piezoelectric vibrating element, and a container having a second accommodating portion for accommodating the temperature-sensitive component are provided. , The container is laminated and fixed to the first insulating substrate having through holes forming the second accommodating portion and having a plurality of mounting terminals at the bottom and the first insulating substrate, and the piezoelectric vibrating element is mounted on the surface. A second insulating substrate provided with a first electrode pad for mounting a temperature-sensitive component and a second electrode pad for mounting a temperature-sensitive component on the back surface, and a first insulating substrate laminated and fixed to the surface of the second insulating substrate. A piezoelectric device including a third substrate constituting an accommodating portion is known (see, for example, Patent Document 1).

In this piezoelectric device, at least one mounting terminal and a first electrode pad are electrically connected by a first heat conductive portion and a first wiring pattern, and the other at least one mounting terminal and a second electrode are connected. By electrically connecting the pads with the second heat conductive portion and the second wiring pattern, it is possible to reduce the temperature difference between the temperature of the piezoelectric vibrating element and the temperature detected by the temperature sensitive component. , It is said that good frequency temperature characteristics can be obtained.

Japanese Unexamined Patent Publication No. 2013-102315

However, depending on the distance in the thickness direction from the mounting terminal of the first insulating substrate to the temperature-sensitive component in the second accommodating portion, the piezoelectric device may be mounted on an external member such as an electronic device. Due to the heat insulating effect of the air warmed when the temperature stays in the accommodating portion, for example, the temperature difference between the temperature of the piezoelectric vibrating element when the temperature drops and the temperature detected by the temperature-sensitive component may increase.
As a result, the frequency-temperature characteristics of the piezoelectric device may deteriorate.

The present invention has been made to solve at least a part of the above problems, and can be realized as the following forms or application examples.

[Application Example 1] The vibrating device according to the present application example includes a vibrating piece, an electronic element, and a substrate having a first main surface and a second main surface which are in a front-to-back relationship with each other. The electronic element is mounted on the first main surface side of the substrate, and the electronic element is housed in a recess provided on the second main surface side of the substrate, and is housed on the second main surface side of the substrate. A plurality of electrode terminals connected to the vibrating piece or the electronic element are provided, and the distance from the mounting surface of the electrode terminal to the electronic element in the first direction orthogonal to the first main surface is 0. It is characterized in that it is 05 mm or more.

According to this, the vibration device has a distance of 0.05 mm or more in the first direction (in other words, the thickness direction of the substrate) from the mounting surface of the electrode terminal to the electronic element. Therefore, for example, an electronic device or the like. When mounted on the external member of the above, the flow of air in the recess is promoted, and the delay in temperature drop of the electronic element due to the retention of air in the recess can be reduced.
As a result, the vibrating device can reduce the temperature difference between the temperature of the vibrating piece and the temperature detected by the temperature-sensitive element, for example, when the electronic element is a temperature-sensitive element (temperature-sensitive component).
As a result, the vibration device can obtain good frequency temperature characteristics.

[Application Example 2] In the vibration device according to the above application example, the distance of the electrode terminal from the mounting surface to the bottom surface of the recess in the first direction is preferably less than 0.3 mm.

According to this, in the vibrating device, the distance from the mounting surface of the electrode terminal to the bottom surface of the recess in the first direction is less than 0.3 mm, so that the temperature of the vibrating piece and the temperature detected by the temperature sensitive element are different. It is possible to reduce the thickness while reducing the temperature difference.
As a result, the vibration device can obtain good frequency temperature characteristics while reducing the thickness.

[Application Example 3] In the vibration device according to the application example, the first virtual center line extending through the center of the electronic element in the first direction and extending along the first main surface, and the first of the vibration pieces. The distance in the first direction from the second virtual center line that passes through the center in the direction and extends along the first main surface is preferably in the range of 0.18 mm or more and 0.32 mm or less.

According to this, in the vibrating device, the distance between the first virtual center line of the electronic element and the second virtual center line of the vibrating piece in the first direction is within the range of 0.18 mm or more and 0.32 mm or less. Therefore, for example, when the electronic element is a temperature-sensitive element, the temperature difference between the temperature of the vibrating piece and the temperature detected by the temperature-sensitive element can be reduced, and the thickness can be further reduced.

[Application Example 4] In the vibration device according to the above application example, one of the electrode terminals is provided with a protrusion so as to have a larger area than the other electrode terminals in a plan view, and the contour of the protrusion has a curved line. It is preferable that it is contained.

According to this, the vibration device is provided with a protrusion so that one of the electrode terminals has a larger area than the other electrode terminals in a plan view, and the contour of the protrusion includes a curved line. In addition to the terminal identification function, this electrode terminal serves as a base point to easily bring out the self-alignment effect of the vibrating device (autonomous position repair phenomenon during reflow mounting when the vibrating device is attached to the external substrate via solder). be able to.

[Application Example 5] In the vibration device according to the above application example, the electronic element is preferably a temperature sensitive element.

According to this, in the vibrating device, since the electronic element is a temperature-sensitive element, the temperature difference between the temperature of the vibrating piece and the temperature detected by the temperature-sensitive element can be reduced.

[Application Example 6] In the vibration device according to the above application example, the temperature sensing element is preferably a thermistor or a temperature measuring semiconductor.

According to this, since the temperature sensitive element is a thermistor or a temperature measuring semiconductor, the vibration device can accurately detect the ambient temperature by the characteristics of the thermistor and the temperature measuring semiconductor.

[Application Example 7] The electronic device according to this application example is characterized by including the vibration device described in any one of the above application examples.

According to this, since the electronic device of this configuration includes the vibration device described in any one of the above application examples, the effect described in any one of the above application examples is exhibited, and excellent performance is achieved. It is possible to provide an electronic device that demonstrates its performance.

[Application Example 8] The moving body according to the present application example is characterized by including the vibration device described in any one of the above application examples.

According to this, since the mobile body of the present configuration includes the vibration device described in any one of the above application examples, the effect described in any one of the above application examples is exhibited, and excellent performance is achieved. It is possible to provide a moving body to exert.

[Application Example 9] The vibration device according to the present application example includes a vibration piece, a temperature sensitive element, and a container in which the vibration piece and the temperature sensitive element are housed, and the temperature of the vibration piece and the feeling. The temperature difference dT from the temperature detected by the temperature element satisfies | dT | ≦ 0.1 (° C.).

As a result, the vibrating device can reduce the temperature difference between the temperature of the vibrating piece and the temperature detected by the temperature sensitive element.
As a result, the vibration device can obtain good frequency temperature characteristics.

[Application Example 10] In the vibration device according to the above application example 9, the temperature sensing element is preferably a thermistor or a temperature measuring semiconductor.

According to this, since the temperature sensitive element is a thermistor or a temperature measuring semiconductor, the vibration device can accurately detect the ambient temperature by the characteristics of the thermistor and the temperature measuring semiconductor.

[Application Example 11] The electronic device according to the present application example is characterized by including the vibration device according to the application example 9 or 10.

According to this, since the electronic device having this configuration includes the vibration device according to the application example 9 or the application example 10, the effect described in the application example 9 or the application example 10 is exhibited, which is excellent. It is possible to provide an electronic device that exhibits its performance.

[Application Example 12] The moving body according to the present application example is characterized by including the vibration device according to the application example 9 or 10.

According to this, since the moving body having this configuration includes the vibration device according to the application example 9 or the application example 10, the effect described in the application example 9 or the application example 10 is exhibited, which is excellent. It is possible to provide a mobile body that exhibits its performance.

It is a schematic diagram which shows the schematic structure of the crystal oscillator of 1st Embodiment, (a) is a plan view seen from the lid (lid body) side, (b) is a sectional view in line AA of (a). , (C) is a plan view seen from the bottom surface side. The circuit diagram concerning the drive of the crystal oscillator including the temperature sensitive element as an electronic element housed in the crystal oscillator of 1st Embodiment. The graph explaining the relationship between the distance L1 and the followability of the temperature change of the thermistor at the time of the temperature change of a crystal vibrating piece. The graph explaining the relationship between the distance L1 and the yield of the temperature hysteresis of a crystal oscillator. A graph showing the temperature difference between the detected temperature of the thermistor and the temperature of the vibrating piece. It is a schematic diagram which shows the schematic structure of the crystal oscillator of the modified example of 1st Embodiment, (a) is a plan view seen from the lid side, (b) is a sectional view in line AA of (a). (C) is a plan view seen from the bottom surface side. It is a schematic diagram which shows the schematic structure of the crystal oscillator of 2nd Embodiment, (a) is a plan view seen from the lid side, (b) is the sectional view in line AA of (a), (c). Is a plan view seen from the bottom side. The schematic perspective view which shows the mobile phone as an electronic device. The schematic perspective view which shows the automobile as a moving body.

Hereinafter, embodiments embodying the present invention will be described with reference to the drawings.

(First Embodiment)
First, a crystal oscillator as an example of a vibration device will be described.
FIG. 1 is a schematic view showing a schematic configuration of the crystal unit of the first embodiment. 1 (a) is a plan view seen from the lid (lid) side, and FIG. 1 (b) is a cross-sectional view taken along the line AA of FIG. 1 (a), FIG. 1 (c). Is a plan view seen from the bottom surface side. In the following plan view from the lid side including FIG. 1A, the lid is omitted. Also, for the sake of clarity, the dimensional ratio of each component is different from the actual one.
FIG. 2 is a circuit diagram related to driving a crystal oscillator including a temperature-sensitive element as an electronic element housed in the crystal oscillator of the first embodiment.

As shown in FIG. 1, the crystal oscillator 1 includes a crystal vibrating piece 10 as a vibrating piece, a thermistor 20 as an example of a temperature-sensitive element as an electronic element, a crystal vibrating piece 10 and a thermistor 20. The package 30 is provided.

The crystal vibrating piece 10 is, for example, an AT-cut type crystal substrate cut out from a rough crystal or the like at a predetermined angle, and has a substantially rectangular planar shape and a vibrating portion 11 in which thick sliding vibration is excited. It integrally has a base 12 connected to the vibrating portion 11.
In the crystal vibrating piece 10, the drawing electrodes 15a and 16a drawn from the substantially rectangular excitation electrodes 15 and 16 formed on one main surface 13 and the other main surface 14 of the vibrating portion 11 are formed on the base 12. There is.

The extraction electrode 15a is drawn from the excitation electrode 15 on one main surface 13 to the base 12 along the longitudinal direction (left-right direction of the paper surface) of the crystal vibrating piece 10 and to the other main surface 14 along the side surface of the base 12. It wraps around and extends to the other main surface 14 of the base 12.
The extraction electrode 16a is pulled out from the excitation electrode 16 of the other main surface 14 to the base 12 along the longitudinal direction of the crystal vibrating piece 10, wraps around the one main surface 13 along the side surface of the base 12, and is formed on the base 12. It extends to one of the main surfaces 13.
The excitation electrodes 15 and 16 and the extraction electrodes 15a and 16a form a metal film having, for example, Cr (chromium) as a base layer and a metal containing Au (gold) or Au as a main component laminated on the base layer. There is.

The thermistor 20 is, for example, a chip-type (square-shaped) temperature-sensitive element (temperature-sensitive resistance element), which has electrodes 21 and 22 at both ends and has a large change in electrical resistance with respect to temperature changes. The body.
As the thermistor 20, for example, a thermistor called an NTC (Negative Temperature Coefficient) thermistor whose resistance is reduced with respect to an increase in temperature is used. The NTC thermistor is often used as a temperature sensor because the relationship between the temperature and the change in resistance value is linear.
The thermistor 20 is housed in the package 30, and by detecting the temperature in the vicinity of the crystal vibrating piece 10, it functions as a temperature sensor to contribute to the correction of frequency fluctuations due to the temperature change of the crystal vibrating piece 10.

The package 30 has a substantially rectangular plane shape and a substantially flat plate shape, and has a package base 31 as a substrate having a first main surface 33 and a second main surface 34 which are in a front-to-back relationship with each other, and a first package base 31. 1 It has a flat lid 32 that covers the main surface 33 side, and is formed in a substantially rectangular parallelepiped shape.
The package base 31 has a flat plate-shaped first layer 31a whose one surface is the first main surface 33 and an opening in the center, and is laminated on the side opposite to the first main surface 33 of the first layer 31a. The second layer 31b whose surface opposite to the laminated surface is the second main surface 34, and the frame-shaped third layer 31c laminated on the first main surface 33 side of the first layer 31a. I have.
On the first layer 31a and the second layer 31b of the package base 31, a ceramic green sheet is molded, laminated and fired to form an aluminum oxide sintered body, a mulite sintered body, an aluminum nitride sintered body, and a silicon carbide. Sintered bodies, glass ceramics Ceramic-based insulating materials such as sintered bodies, crystals, glass, silicon (high resistance silicon), and the like are used.
The same material as the package base 31 or a metal such as Kovar or 42 alloy is used for the third layer 31c and the lid 32 of the package base 31.

Internal terminals 33a and 33b are provided on the first main surface 33 of the package base 31 at positions facing the lead-out electrodes 15a and 16a of the crystal vibrating piece 10.
In the crystal vibrating piece 10, the extraction electrodes 15a and 16a are joined to the internal terminals 33a and 33b via a conductive adhesive 40 such as an epoxy-based, silicone-based or polyimide-based material in which a conductive substance such as a metal filler is mixed. Has been done. As a result, the crystal vibrating piece 10 is mounted on the first main surface 33 side.

In the crystal transducer 1, the third layer 31c of the package base 31 is covered with the lid 32 in a state where the crystal vibrating piece 10 is joined to the internal terminals 33a and 33b of the package base 31, and the package base 31 and the lid 32 are connected. The internal space S including the first layer 31a, the third layer 31c, and the lid 32 of the package base 31 is airtightly sealed by seam welding or joining with a joining member such as low melting point glass or an adhesive. It has been stopped.
FIG. 1 shows, as an example, a form in which a metal third layer 31c and a metal lid 32 are joined by seam welding. In this case, the third layer 31c is brazed to the metallized layer (not shown) of the first layer 31a.
The airtightly sealed internal space S of the package 30 is in a reduced vacuum state (high degree of vacuum state) or in a state filled with an inert gas such as nitrogen, helium, or argon.

On the second main surface 34 side of the package base 31, a recess 35 is provided by the opening of the second layer 31b and the laminated surface of the first layer 31a. The planar shape of the recess 35 is formed, for example, in a track shape.
Electrode pads 36a and 36b are provided on the bottom surface 36 of the recess 35 (the laminated surface of the first layer 31a) at positions facing the electrodes 21 and 22 of the thermistor 20.
In the thermistor 20, the electrodes 21 and 22 are bonded to the electrode pads 36a and 36b via a bonding member 41 such as a conductive adhesive or solder. As a result, the thermistor 20 is housed in the recess 35.
The thermistor 20 is arranged in a substantially central portion of the recess 35 so that the longitudinal direction (the direction connecting the electrode 21 and the electrode 22) is along the longitudinal direction (the left-right direction of the paper surface) of the package base 31.

Electrode terminals 37a, 37b, 37c, and 37d are provided at the four corners of the second main surface 34 of the package base 31, respectively.
Of the four electrode terminals 37a to 37d, for example, two electrode terminals 37b, 37d located diagonally on one side are connected to internal terminals 33a, 33b connected to the extraction electrodes 15a, 16a of the crystal oscillator 10, and the other. The remaining two electrode terminals 37a and 37c located diagonally to the above are connected to the electrode pads 36a and 36b connected to the electrodes 21 and 22 of the thermistor 20.

The four electrode terminals 37a to 37d are formed so that the planar shape is rectangular and a part of the recess 35 side is cut out. The electrode terminal 37c includes a protrusion 38 extending toward the electrode terminal 37b so that the area is larger than that of the other electrode terminals 37a, 37b, 37d in a plan view, and the tip of the protrusion 38 has a substantially semicircular shape. It is formed (in other words, the contour of the protrusion 38 contains a curve).

When the lid 32 and the third layer 31c of the package base 31 are made of metal, the electrode terminals 37c include the first layer 31a and the second layer 31b of the package base 31, respectively, as shown by the broken lines in FIG. 1 (b). It was formed in a penetrating conductive via (a conductive electrode in which a through hole is filled with a metal or a conductive material) and an internal wiring, or a casting (concave) (not shown) provided at an outer corner of the package base 31. It is preferable that any of the conductive films is electrically connected to the lid 32 via the third layer 31c from the viewpoint of improving the shielding property. When the third layer 31c is an insulating material, a conductive via is also provided in the third layer 31c.
Further, the crystal oscillator 1 can be further improved in shielding property by grounding the electrode terminal 37c as a ground terminal (GND terminal).

The internal terminals 33a and 33b, the electrode pads 36a and 36b, and the electrode terminals 37a to 37d are obtained by plating a metallized layer such as W (tungsten) or Mo (molybdenum) with a coating film such as Ni (nickel) or Au. It consists of a metal film laminated by.

The crystal oscillator 1 is formed in a first direction (thickness direction of the package base 31) orthogonal to the first main surface 33 from the mounting surface (mounting surface to the external member) of the electrode terminals 37a to 37d to the thermistor 20. The distance L1 is specified to be 0.05 mm or more.
Further, the crystal oscillator 1 is defined to have a distance L2 in the first direction from the mounting surface of the electrode terminals 37a to 37d to the bottom surface 36 of the recess 35 of less than 0.3 mm.

As an example, the crystal transducer 1 uses a material having a thickness of 0.25 mm ± 0.01 mm (0.24 mm or more and 0.26 mm or less) for the second layer 31b of the package base 31, and has a thickness of electrode terminals 37a to 37d. 0.02 mm ± 0.01 mm (0.01 mm or more and 0.03 mm or less), the thickness of the electrode pads 36a and 36b is 0.02 mm ± 0.01 mm (0.01 mm or more and 0.03 mm or less), and the joining member 41 A thin product with a thickness of 0.01 mm ± 0.005 mm (0.005 mm or more and 0.015 mm or less) and a thickness of 0.12 mm ± 0.015 mm (0.105 mm or more and 0.135 mm or less) on the Thermister 20. Is used.
As a result, the distance L1 of the crystal oscillator 1 is 0.12 mm ± 0.05 mm (0.07 mm or more and 0.17 mm or less), and the minimum is 0.07 mm. Therefore, the specification of 0.05 mm or more is sufficiently specified. Will meet.
Further, since the distance L2 of the crystal oscillator 1 is 0.27 mm ± 0.02 mm (0.25 mm or more and 0.29 mm or less) and the maximum is 0.29 mm, the specification of less than 0.3 mm is sufficiently satisfied. It will be.
From these facts, it can be said that the crystal oscillator 1 can be sufficiently mass-produced by clearing the provisions of the distance L1 and the distance L2 even if the tolerance (variation) is taken into consideration.

Further, the crystal oscillator 1 passes through the center of the thermistor 20 in the first direction, passes through the first virtual center line O1 extending along the first main surface 33, and passes through the center of the crystal vibrating piece 10 in the first direction. The distance L3 in the first direction from the second virtual center line O2 extending along the first main surface 33 is within the range of 0.18 mm or more and 0.32 mm or less.

As an example, the crystal oscillator 1 uses a material having a thickness of 0.09 mm to 0.11 mm for the first layer 31a of the package base 31, and has internal terminals 33a and 33b having a thickness of 0.003 mm to 0.013 mm. The thickness of the conductive adhesive 40 is 0.01 mm to 0.03 mm, the thickness of the crystal oscillator 10 (assuming the resonance frequency range is about 19 to 52 MHz) is 0.032 mm to 0.087 mm, and the electrode pads 36a and 36b. The thickness of the joint member 41 is controlled in the range of 0.01 mm to 0.03 mm, the thickness of the joining member 41 is controlled in the range of 0.005 mm to 0.015 mm, and the thickness of the thermister 20 is controlled in the range of 0.105 mm to 0.135 mm. The thin product that is used is used.
As a result, since the distance L3 of the crystal oscillator 1 is in the range of 0.187 mm to 0.309 mm, the specification of 0.18 mm or more and 0.32 mm or less is sufficiently satisfied, and the distance L3 is long even when the tolerance is taken into consideration. It can be said that it can be mass-produced sufficiently by clearing the regulations.
When the crystal vibrating piece 10 is tilted (the distance L3 is closer to the first main surface 33 as it goes from the base 12 to the tip on the opposite side), the position of the distance L3 in the left-right direction of the paper surface is shown in FIG. The distance between the first virtual center line O1 and the second virtual center line O2 within the range of the internal terminals 33a (33b) of b).

As shown in FIG. 2, the crystal oscillator 1 vibrates, for example, by a drive signal applied from an oscillation circuit 61 integrated in an IC chip 70 of an electronic device via electrode terminals 37b and 37d. The piece 10 is excited by the thickness sliding vibration and resonates (oscillates) at a predetermined frequency, and outputs a resonance signal (oscillation signal) from the electrode terminals 37b and 37d.
At this time, in the crystal oscillator 1, the thermistor 20 detects the temperature in the vicinity of the crystal vibrating piece 10 as a temperature sensor, converts it into a change in the voltage value supplied from the power supply 62, and uses the electrode terminal 37a as a detection signal. Output.

The output detection signal is, for example, A / D converted by the A / D conversion circuit 63 integrated in the IC chip 70 of the electronic device, and input to the temperature compensation circuit 64 also integrated in the IC chip 70. Will be done. Then, the temperature compensation circuit 64 outputs a correction signal based on the temperature compensation data to the oscillation circuit 61 according to the input detection signal.
The oscillation circuit 61 applies a drive signal corrected based on the input correction signal to the crystal vibration piece 10 and corrects the resonance frequency of the crystal vibration piece 10 which fluctuates with a temperature change so as to be a predetermined frequency. To do. The oscillation circuit 61 amplifies the oscillation signal of the corrected frequency and outputs it to the outside.

As described above, in the crystal oscillator 1 of the first embodiment, the distance L1 in the first direction from the mounting surface of the electrode terminals 37a to 37d to the thermistor 20 is 0.05 mm or more.
As described above, the crystal oscillator 1 uses a thin thermistor 20 or the like to set the distance L1 from the mounting surface of the electrode terminals 37a to 37d to the thermistor 20 to 0.05 mm or more, so that the crystal oscillator 1 can be used in electronic devices and the like. When mounted on an external member, the flow of air in the recess 35 is promoted, and the delay in the temperature drop of the thermistor 20 due to the retention of air in the recess 35 can be reduced.

Here, the above contents will be described in detail.
FIG. 3 is a graph for explaining the relationship between the distance L1 and the followability of the temperature change of the thermistor when the temperature of the crystal vibrating piece changes, and FIG. 4 shows the yield of the temperature hysteresis of the crystal oscillator and the distance L1. It is a graph explaining the relationship. The graph in FIG. 3 is based on the analysis results of the inventor of the present application by simulation and experiment.
The horizontal axis of FIG. 3 represents the elapsed time, and the vertical axis represents the temperature. The horizontal axis of FIG. 4 represents the distance L1, and the vertical axis represents the yield of temperature hysteresis of the crystal unit.

As shown in FIG. 3, when the distance L1 from the mounting surface of the electrode terminals 37a to 37d to the thermistor 20 is 0.05 mm, the temperature change detected by the thermistor 20 is caused by the temperature change of the crystal vibrating piece 10. It follows with almost no delay both when the temperature rises and when the temperature drops. That is, when the distance L1 is 0.05 mm, there is almost no temperature difference between the temperature of the crystal vibrating piece 10 and the temperature detected by the thermistor 20.
On the other hand, when the distance L1 is less than 0.05 mm, the temperature change detected by the thermistor 20 when the temperature of the crystal vibrating piece 10 drops as the distance L1 decreases to 0.04 mm and 0.03 mm. (Temperature drop) is delayed, and the temperature difference between the temperature of the crystal oscillator 10 and the temperature detected by the thermistor 20 is large.
It is considered that this is because the air stays in the recess 35 due to the decrease in the distance L1 and the temperature decrease of the thermistor 20 is hindered by the heat insulating effect of the air warmed when the temperature rises.

As a result, as shown in FIG. 4, when the distance L1 is 0.05 mm or more, the yield of the temperature hysteresis of the crystal oscillator 1 (the difference between the frequency transition when the temperature rises and the frequency transition when the temperature falls) Is 100%.
On the other hand, when the distance L1 is less than 0.05 mm, the yield of temperature hysteresis of the crystal oscillator 1 does not reach 100%, and the smaller the distance L1 is to 0.04 mm and 0.03 mm, the worse the yield becomes.
From such a result, the crystal oscillator 1 can reduce the temperature difference between the temperature of the crystal vibrating piece 10 and the temperature detected by the thermistor 20 by setting the distance L1 to 0.05 mm or more.
As a result, the crystal unit 1 can obtain good frequency temperature characteristics.

Next, the inventor of the present application has conducted a verification experiment on the followability of the temperature change of the thermistor 20 when the temperature of the crystal vibrating piece 10 changes, and the results will be described below.
According to the analysis results of FIGS. 3 and 4 described above, the sir with respect to the temperature of the crystal vibrating piece 10 at a distance L1 = 0.05 mm where there was almost no temperature difference between the temperature of the crystal vibrating piece 10 and the temperature detected by the thermistor 20. An experiment was conducted on the temperature followability detected by Mr. 20.

The crystal oscillator 1 according to the first embodiment is mounted on an external substrate, heat is applied to the external substrate, the temperature detected by the thermistor 20 is compared with the temperature of the crystal vibrating piece 10 at that time, and the temperature is measured. We evaluated how much the difference was.
First, the temperature of the external substrate was raised from 29.0 ° C to 32.0 ° C. At that time, the frequency of the crystal vibrating piece 10 at each detection temperature from 29.5 ° C. to 31.5 ° C. detected by the thermistor 20 in 0.1 ° C. steps was measured, and the thermistor 20 measured the frequency. The frequency deviation was determined with reference to the detected frequency of the crystal vibrating piece 10 at 29.5 ° C.
Next, the temperature of the external substrate was lowered from 32.0 ° C to 29.0 ° C. At that time, the frequency of the crystal vibrating piece 10 at each detection temperature from 31.5 ° C. to 29.5 ° C. detected by the thermistor 20 in the 0.1 ° C. step was measured, and the thermistor 20 measured the frequency. The frequency deviation was determined with reference to the frequency of the crystal vibrating piece 10 at 29.5 ° C. detected when the temperature was raised.
They are shown in Table 1 below.

Here, since the crystal vibrating piece 10 is an AT-cut type crystal vibrating piece, its frequency temperature characteristic exhibits a cubic curve. The inventor of the present application calculates the temperature of the crystal vibrating piece 10 from the frequency deviation of the crystal vibrating piece 10 at each temperature detected by the thermistor 20 based on the frequency temperature characteristic data of the crystal vibrating piece 10 measured in advance. Calculated.
They are shown in Table 2 below.

Next, from Table 2, the temperature difference between the detected temperature of the thermistor 20 and the temperature of the crystal vibrating piece 10 at each temperature detected by the thermistor 20 was calculated.
They are shown in Table 3 below.

FIG. 5 is a graph showing the temperature difference between the detected temperature of the thermistor and the temperature of the crystal vibrating piece, and is a graph of the calculation results in Table 3. The horizontal axis represents the temperature (° C) detected by the thermistor, and the vertical axis represents the temperature difference (° C) between the temperature detected by the thermistor and the temperature of the crystal vibrating piece.
It was found that the temperature difference dT between the detected temperature of the thermistor 20 and the temperature of the crystal vibrating piece 10 was −0.07 ° C. or higher and 0.00 ° C. or lower. That is, the temperature followability detected by the thermistor 20 with respect to the temperature of the crystal vibrating piece 10 from this verification experiment is as follows.
| DT | ≤0.1 (° C)
It was found that a vibration device (crystal oscillator 1) having good frequency-temperature characteristics can be obtained if the above conditions are satisfied.
Further, | dT | ≤0.1 (° C.) as the temperature followability detected by the thermistor 20 is not limited to the schematic configuration of the crystal oscillator 1 of the first embodiment as shown in FIG. It can also be applied to a vibrating device having a so-called single-seal type package in which a vibrating piece and a temperature-sensitive element are housed together in one accommodating portion.

Further, since the distance L2 in the first direction from the mounting surface of the electrode terminals 37a to 37d to the bottom surface 36 of the recess 35 of the crystal oscillator 1 is less than 0.3 mm, the temperature of the crystal vibrating piece 10 and the thermistor It is possible to reduce the thickness while reducing the temperature difference from the temperature detected by 20.
As a result, the crystal unit 1 can obtain good frequency temperature characteristics while reducing the thickness.

Further, in the crystal oscillator 1, the distance L3 between the first virtual center line O1 of the thermistor 20 and the second virtual center line O2 of the crystal vibrating piece 10 in the first direction is 0.18 mm or more and 0.32 mm or less. Since it is within the range, the temperature difference between the temperature of the crystal oscillator 10 and the temperature detected by the thermistor 20 can be reduced, and the thickness can be further reduced.
When the distance L3 is less than 0.18 mm, the thickness of the first layer 31a of the package base 31 is less than 0.09 mm (assuming that it is difficult to further reduce the thickness of the thermistor 20 for the time being). Also becomes thinner, and the strength of the package base 31 becomes a problem.
Further, when the distance L3 exceeds 0.32 mm, the temperature difference between the temperature of the crystal vibrating piece 10 and the temperature detected by the thermistor 20 increases and the frequency temperature characteristics deteriorate, so that the crystal oscillator There is a risk that it will be difficult to deal with the high accuracy of 1.

Further, the crystal oscillator 1 is provided with a protruding portion 38 so that the electrode terminal 37c out of the four electrode terminals 37a to 37d has a larger area than the other electrode terminals 37a, 37b, 37d in a plan view. The tip of the portion 38 is formed in a substantially semicircular shape (in other words, the contour of the protruding portion 38 includes a curve).
From this, in the crystal oscillator 1, the protruding portion 38 functions as an identification mark of the electrode terminal 37c, and the electrode terminal 37c having a large area serves as a base point, and the self-alignment effect of the crystal oscillator 1 (the crystal oscillator 1). The autonomous position repair phenomenon at the time of reflow mounting when mounting to an external board via solder) can be easily drawn out.

Further, since the electronic element of the crystal oscillator 1 is a temperature-sensitive element, the thickness of the crystal oscillator 1 can be reduced while reducing the temperature difference between the temperature of the crystal vibrating piece 10 and the temperature detected by the temperature-sensitive element.

Further, since the temperature sensitive element of the crystal oscillator 1 is the thermistor 20, the ambient temperature can be accurately detected by the characteristics of the thermistor 20. As the temperature sensing element, a temperature measuring semiconductor may be used instead of the thermistor 20, and the ambient temperature can be accurately detected by the characteristics of the temperature measuring semiconductor. Examples of the temperature measuring semiconductor include a diode or a transistor.
More specifically, in the case of a diode, the temperature is detected by using the forward characteristics of the diode, passing a constant current from the anode terminal to the cathode terminal of the diode, and measuring the forward voltage that changes with temperature. can do. Further, in the case of a transistor, the temperature can be detected in the same manner as described above by short-circuiting the base and the collector and allowing the collector and the emitter to function as a diode.
The crystal oscillator 1 can reduce the superposition of noise by using a diode or a transistor as the temperature sensitive element.

(Modification example)
Next, a modified example of the first embodiment will be described.
FIG. 6 is a schematic view showing a schematic configuration of a crystal unit of a modified example of the first embodiment. 6 (a) is a plan view seen from the lid side, FIG. 6 (b) is a cross-sectional view taken along the line AA of FIG. 6 (a), and FIG. 6 (c) is a bottom surface side. It is a plan view seen from.
The common parts with the first embodiment are designated by the same reference numerals, detailed description thereof will be omitted, and the parts different from the first embodiment will be mainly described.

As shown in FIG. 6, the crystal oscillator 2 of the modified example has a different arrangement direction of the thermistor 20 as compared with the first embodiment.
In the crystal oscillator 2, the longitudinal direction of the thermistor 20 (the direction connecting the electrode 21 and the electrode 22) intersects the longitudinal direction of the package base 31 (the left-right direction on the paper surface) (here, orthogonal). The thermistor 20 is arranged.

As a result, in addition to the effect of the first embodiment, the crystal oscillator 2 has a fixed strength (bonding strength) of the thermistor 20 due to the warp of the package base 31, which is said to have a large warp in the longitudinal direction. The drop can be reduced.
The configuration of the above modification can also be applied to the following embodiments.

(Second Embodiment)
Next, another configuration of the crystal oscillator as a vibration device will be described.
FIG. 7 is a schematic view showing a schematic configuration of the crystal unit of the second embodiment. 7 (a) is a plan view seen from the lid side, FIG. 7 (b) is a cross-sectional view taken along the line AA of FIG. 7 (a), and FIG. 7 (c) is a bottom surface side. It is a plan view seen from.
The common parts with the first embodiment are designated by the same reference numerals, detailed description thereof will be omitted, and the parts different from the first embodiment will be mainly described.

As shown in FIG. 7, the crystal unit 3 of the second embodiment has different configurations of the package base 31 and the lid 32 as compared with the first embodiment.
In the crystal unit 3, the third layer 31c of the package base 31 is removed, and a joining member 39 with the lid 32 is arranged instead.
The lid 32 is formed in the shape of a cap having a brim portion 32a provided on the entire circumference by using a metal such as Kovar or 42 alloy.
In the crystal oscillator 3, the internal space S for accommodating the crystal vibrating piece 10 is secured by the bulge of the cap portion of the lid 32.

The lid 32 has a brim portion 32a joined to the first main surface 33 of the package base 31 via a joining member 39 having conductivity such as a seam ring, a brazing material, and a conductive adhesive.
As a result, the lid 32 is electrically connected to the electrode terminal 37c via the conductive via, the internal wiring, and the like in the package base 31, and the shielding effect is exhibited.
The lid 32 may be electrically connected to the electrode terminal 37c via a conductive film formed on a casting (not shown) provided at the outer corner of the joining member 39 and the package base 31.

As described above, in the crystal unit 3 of the second embodiment, since the third layer 31c of the package base 31 is removed, the package base 31 can be easily manufactured as compared with the first embodiment.
In the crystal oscillator 3, the lid 32 may not be electrically connected to the electrode terminal 37c as long as the shield is not hindered. As a result, the joining member 39 may be an insulating member.

(Electronics)
Next, as an electronic device provided with the above-mentioned vibration device, a mobile phone will be described as an example.
FIG. 8 is a schematic perspective view showing a mobile phone as an electronic device.
The mobile phone 700 includes a crystal oscillator as a vibration device described in each of the above embodiments and modifications.
The mobile phone 700 shown in FIG. 8 uses the above-mentioned crystal oscillator (any of 1 to 3) as a timing device such as a reference clock oscillation source, and further includes a liquid crystal display device 701, a plurality of operation buttons 702, and a receiver. It is configured to include a mouthpiece 703 and a mouthpiece 704. The form of the mobile phone is not limited to the type shown in the figure, and may be a so-called smartphone type.

The above-mentioned vibration devices such as crystal oscillators are not limited to the above-mentioned mobile phones, but are not limited to the above-mentioned mobile phones, but also electronic books, personal computers, televisions, digital still cameras, video cameras, video recorders, navigation devices, pagers, electronic organizers, calculators, word processors, workstations. , Videophone, POS terminal, game equipment, medical equipment (for example, electronic thermometer, sphygmomanometer, blood glucose meter, electrocardiogram measuring device, ultrasonic diagnostic device, electronic endoscope), fish finder, various measuring devices, instruments, flight It can be suitably used as a timing device for electronic devices including a simulator, etc., and in any case, it is possible to provide an electronic device that exhibits the effects described in the above embodiments and modifications and exhibits excellent performance. it can.

(Mobile)
Next, as a moving body equipped with the above-mentioned vibration device, an automobile will be described as an example.
FIG. 9 is a schematic perspective view showing an automobile as a moving body.
The automobile 800 includes a crystal oscillator as a vibration device described in each of the above embodiments and modifications.
The automobile 800 is equipped with the above-mentioned crystal oscillator (any of 1 to 3), for example, various electronically controlled devices (for example, an electronically controlled fuel injection device, an electronically controlled ABS device, and an electronically controlled constant). It is used as a timing device such as a reference clock oscillation source for speed traveling devices.
According to this, since the automobile 800 is provided with the crystal oscillator, the effects described in the above embodiments and modifications can be obtained, and excellent performance can be exhibited.

The vibration device such as the crystal oscillator described above is not limited to the automobile 800, and the timing of a reference clock oscillation source of a mobile body including a self-propelled robot, a self-propelled transport device, a train, a ship, an airplane, an artificial satellite, etc. It can be suitably used as a device, and in any case, it is possible to provide a moving body that exhibits the effects described in the above embodiments and modifications, and exhibits excellent performance.

The shape of the vibrating piece of the crystal oscillator is not limited to the flat plate type shown in the figure, but is a type with a thick central part and a thin peripheral part (for example, convex type, bevel type, mesa type), and conversely the center. A type having a thin portion and a thick peripheral portion (for example, an inverted mesa type) may be used, or a tuning fork type shape may be used.

The material of the vibrating piece is not limited to crystal, but lithium tantalate (LiTaO ₃ ), lithium tetraborate (Li ₂ B ₄ O ₇ ), lithium niobate (LiNbO ₃ ), and lead zirconate titanate. Piezoelectric materials such as lead acid (PZT), zinc oxide (ZnO) and aluminum nitride (AlN), or semiconductors such as silicon (Si) may be used.
Further, the driving method of the thickness sliding vibration may be electrostatic driving by Coulomb force in addition to the one by the piezoelectric effect of the piezoelectric body.

1, 2, 3 ... Crystal oscillator as a vibrating device, 10 ... Crystal vibrating piece as a vibrating piece, 11 ... Vibrating part, 12 ... Base, 13 ... One main surface, 14 ... The other main surface, 15, 16 ... Excitation electrode, 15a, 16a ... Extraction electrode, 20 ... Thermister as an example of a temperature sensitive element as an electronic element, 21,22 ... Electrode, 30 ... Package, 31 ... Package base as a substrate, 31a ... First layer , 31b ... 2nd layer, 31c ... 3rd layer, 32 ... lid, 32a ... brim, 33 ... 1st main surface, 33a, 33b ... internal terminal, 34 ... 2nd main surface, 35 ... concave, 36 ... bottom surface , 36a, 36b ... Electrode pads, 37a, 37b, 37c, 37d ... Electrode terminals, 38 ... Projections, 39 ... Joining members, 40 ... Conductive adhesives, 41 ... Joining members, 61 ... Oscillating circuits, 62 ... Power supplies, 63 ... A / D conversion circuit, 64 ... temperature compensation circuit, 70 ... IC chip, 700 ... mobile phone as an electronic device, 701 ... liquid crystal display device, 702 ... operation button, 703 ... earpiece, 704 ... mouthpiece, 800 ... Automobile as a moving body, S ... Internal space.

Claims (12)

Vibrating pieces and
With electronic devices
A substrate having a first main surface and a second main surface which are in a front-to-back relationship with each other is provided.
The vibrating piece is mounted on the first main surface side of the substrate.
The electronic element is housed in a recess provided on the second main surface side of the substrate.
A plurality of electrode terminals connected to the vibrating piece or the electronic element are provided on the second main surface side of the substrate.
A vibration device characterized in that the distance from the mounting surface of the electrode terminal to the electronic element in the first direction orthogonal to the first main surface is 0.05 mm or more. In claim 1,
A vibration device characterized in that the distance from the mounting surface of the electrode terminal to the bottom surface of the recess in the first direction is less than 0.3 mm. In claim 1 or 2,
Through the center of the electronic element in the first direction, the first virtual center line extending along the first main surface, and the center of the vibrating piece in the first direction, along the first main surface. A vibration device characterized in that the distance from the extending second virtual center line in the first direction is within the range of 0.18 mm or more and 0.32 mm or less. In any one of claims 1 to 3,
One of the electrode terminals is provided with a protrusion so as to have a larger area than the other electrode terminals in a plan view.
A vibration device characterized in that the contour of the protruding portion includes a curved line. In any one of claims 1 to 4,
The electronic element is a vibration device characterized by being a temperature sensitive element. In claim 5,
The temperature sensitive element is a vibration device characterized by being a thermistor or a temperature measuring semiconductor. An electronic device comprising the vibration device according to any one of claims 1 to 6. A mobile body including the vibration device according to any one of claims 1 to 6. Vibrating pieces and
With a temperature sensitive element
The vibrating piece and the container in which the temperature sensitive element is housed are provided.
The temperature difference dT between the temperature of the vibrating piece and the temperature detected by the temperature sensitive element is
A vibrating device characterized in that | dT | ≤0.1 (° C.) is satisfied. In claim 9.
The temperature sensitive element is a vibration device characterized by being a thermistor or a temperature measuring semiconductor. An electronic device comprising the vibration device according to claim 9 or 10. A mobile body comprising the vibration device according to claim 9 or 10.

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