Vibration devices, electronic devices and mobile devices

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

[Technical Field]

[0001] The present invention relates to a vibration device, and an electronic device and a mobile object that are equipped with the vibration device. [Background technology]

[0002] Conventionally, as an example of a vibration device, a piezoelectric device is known which includes a piezoelectric vibration element, a temperature-sensitive component, and a container having a first storage section for storing the piezoelectric vibration element and a second storage section for storing the temperature-sensitive component, wherein the container includes a first insulating substrate having a through hole that forms the second storage section and a plurality of mounting terminals on its bottom, a second insulating substrate that is laminated and fixed to the first insulating substrate and has a first electrode pad for mounting the piezoelectric vibration element on its front surface and a second electrode pad for mounting the temperature-sensitive component on its back surface, and a third substrate that is laminated and fixed to the surface of the second insulating substrate and forms the first storage section (see, for example, Patent Document 1).

[0003] This piezoelectric device has at least one mounting terminal and a first electrode pad electrically connected by a first heat conduction portion and a first wiring pattern, and at least another mounting terminal and a second electrode pad electrically connected by a second heat conduction portion and a second wiring pattern, which makes it possible to reduce the temperature difference between the temperature of the piezoelectric vibration element and the temperature detected by the temperature-sensing component, and is said to achieve good frequency-temperature characteristics. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2013-102315 Summary of the Invention [Problem to be solved by the invention]

[0005] However, when the piezoelectric device is mounted on an external component such as an electronic device, depending on the thickness distance from the mounting terminal of the first insulating substrate to the temperature-sensing component in the second accommodating section, the insulating effect of the air that is warmed when the temperature rises and remains in the second accommodating section may increase the temperature difference between the temperature of the piezoelectric vibration element when the temperature drops and the temperature detected by the temperature-sensing component, for example. As a result, the frequency temperature characteristics of the piezoelectric device may deteriorate. [Means for solving the problem]

[0006] The present invention has been made to solve at least part of the above problems, and can be realized as the following aspects or application examples.

[0007] [Application Example 1] The vibration device of this application example comprises a vibration element, an electronic element, and a substrate having a first main surface and a second main surface that are opposite each other, the vibration element 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 vibration element or the electronic element are provided on the second main surface side of the substrate, and the distance from the mounting surface of the electrode terminal to the electronic element in a first direction perpendicular to the first main surface is 0.05 mm or more.

[0008] According to this, since the distance 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 of the vibration device is 0.05 mm or more, when the device is mounted on an external component such as an electronic device, the flow of air within the recess is promoted, thereby reducing the delay in the temperature drop of the electronic element caused by stagnation of air within the recess. As a result, in the case where the electronic element of the resonator device is a temperature-sensitive element (temperature-sensitive component), for example, the temperature difference between the temperature of the resonator element and the temperature detected by the temperature-sensitive element can be reduced. This allows the vibration device to have good frequency temperature characteristics.

[0009] [Application Example 2] In the resonation device according to the above application example, it is preferable that the distance in the first direction from the mounting surface of the electrode terminal to the bottom surface of the recess be less than 0.3 mm.

[0010] As a result, the vibration device has a distance in the first direction from the mounting surface of the electrode terminal to the bottom surface of the recess of less than 0.3 mm, so that the temperature difference between the temperature of the vibration element and the temperature detected by the temperature-sensing element can be reduced while making the device thinner. This allows the resonator device to have good frequency-temperature characteristics while being made thinner.

[0011] [Application Example 3] In the vibrating device according to the above application example, it is preferable that the distance in the first direction between a first virtual center line that passes through the center of the electronic element in the first direction and extends along the first main surface and a second virtual center line that passes through the center of the vibrating element in the first direction and extends along the first main surface is within the range of 0.18 mm or more and 0.32 mm or less.

[0012] According to this, the distance in the first direction between the first virtual center line of the electronic element and the second virtual center line of the vibrating bar is within the range of 0.18 mm or more and 0.32 mm or less.Therefore, for example, if the electronic element is a thermosensitive element, the temperature difference between the temperature of the vibrating bar and the temperature detected by the thermosensitive element can be reduced, while the vibrating device can be made even thinner.

[0013] [Application Example 4] In the vibration device according to the above application example, it is preferable that one of the electrode terminals has a protrusion that has a larger area than the other electrode terminals in a planar view, and that the contour of the protrusion includes a curve.

[0014] According to this, one of the electrode terminals of the vibration device has a protrusion that makes it larger in area than the other electrode terminals when viewed in a plane, and the contour of the protrusion includes a curve.In addition to the function of identifying the electrode terminal, this electrode terminal can serve as a base point to easily bring out the self-alignment effect of the vibration device (the autonomous position repair phenomenon that occurs during reflow mounting when the vibration device is attached to an external board via solder).

[0015] [Application Example 5] In the vibration device according to the above application example, the electronic element is preferably a temperature-sensitive element.

[0016] According to this, since the electronic element of the resonator device is a temperature-sensitive element, it is possible to reduce the temperature difference between the temperature of the resonator element and the temperature detected by the temperature-sensitive element.

[0017] [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.

[0018] According to this, since the temperature-sensing element of the vibration device is a thermistor or a temperature-measuring semiconductor, the ambient temperature can be accurately detected by the characteristics of the thermistor and the temperature-measuring semiconductor.

[0019] [Application Example 7] An electronic device according to this application example is characterized by including the vibration device according to any one of the above application examples.

[0020] As a result, since the electronic device of this configuration is equipped with the vibration device described in any one of the above application examples, the effects described in any one of the above application examples are achieved, and an electronic device with excellent performance can be provided.

[0021] [Application Example 8] A moving object according to this application example is characterized by including the vibration device according to any one of the application examples above.

[0022] As a result, since the moving body of this configuration is equipped with a vibration device described in any one of the above application examples, the effects described in any one of the above application examples are achieved, and a moving body with excellent performance can be provided.

[0023] [Application Example 9] The vibration device of this application example comprises a vibration element, a temperature-sensing element, and a container in which the vibration element and the temperature-sensing element are housed, and is characterized in that the temperature difference dT between the temperature of the vibration element and the temperature detected by the temperature-sensing element satisfies |dT|≦0.1 (°C).

[0024] As a result, the vibration device can reduce the temperature difference between the temperature of the vibration element and the temperature detected by the temperature sensitive element. This allows the vibration device to have good frequency temperature characteristics.

[0025] [Application Example 10] In the resonation device according to the above-mentioned application example 9, the temperature-sensing element is preferably a thermistor or a temperature-measuring semiconductor.

[0026] According to this, since the temperature-sensing element of the vibration device is a thermistor or a temperature-measuring semiconductor, the ambient temperature can be accurately detected by the characteristics of the thermistor and the temperature-measuring semiconductor.

[0027] [Application Example 11] An electronic device according to this application example is characterized by including the vibration device according to application example 9 or 10 above.

[0028] As a result, since the electronic device of this configuration is equipped with the vibration device described in Application Example 9 or Application Example 10 above, the effects described in Application Example 9 or Application Example 10 above are achieved, and an electronic device with excellent performance can be provided.

[0029] [Application Example 12] A moving object according to this application example is characterized by including the vibration device according to application example 9 or 10 above.

[0030] As a result, since the moving body of this configuration is equipped with the vibration device described in Application Example 9 or Application Example 10 above, the effects described in Application Example 9 or Application Example 10 above are achieved, and a moving body with excellent performance can be provided. [Brief explanation of the drawings]

[0031] [Figure 1] 2A and 2B are schematic diagrams showing the general configuration of a quartz crystal resonator according to a first embodiment, in which (a) is a plan view seen from the lid (cover) side, (b) is a cross-sectional view taken along line AA in (a), and (c) is a plan view seen from the bottom side. [Figure 2] FIG. 2 is a circuit diagram related to driving the quartz crystal resonator including a temperature-sensing element as an electronic element housed in the quartz crystal resonator according to the first embodiment. [Figure 3] 10 is a graph illustrating the relationship between the distance L1 and the temperature change followability of the thermistor when the temperature of the quartz crystal resonator element changes. [Figure 4] 10 is a graph illustrating the relationship between the distance L1 and the temperature hysteresis yield of a crystal unit. [Figure 5] 6 is a graph showing the temperature difference between the temperature detected by the thermistor and the temperature of the vibrating element. [Figure 6] 5A and 5B are schematic diagrams showing the general configuration of a quartz crystal resonator according to a modified example of the first embodiment, in which (a) is a plan view seen from the lid side, (b) is a cross-sectional view taken along line AA in (a), and (c) is a plan view seen from the bottom side. [Figure 7] 5A and 5B are schematic diagrams showing the general configuration of a quartz crystal resonator according to a second embodiment, in which (a) is a plan view seen from the lid side, (b) is a cross-sectional view taken along line AA in (a), and (c) is a plan view seen from the bottom side. [Figure 8] FIG. 1 is a schematic perspective view showing a mobile phone as an electronic device. [Figure 9] FIG. 1 is a schematic perspective view showing an automobile as a moving object. DETAILED DESCRIPTION OF THE INVENTION

[0032] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings.

[0033] (First embodiment) First, a crystal resonator will be described as an example of a resonator device. FIG. 1 is a schematic diagram showing the general configuration of a quartz crystal resonator according to a first embodiment. FIG. 1(a) is a plan view seen from the lid side, FIG. 1(b) is a cross-sectional view taken along line AA in FIG. 1(a), and FIG. 1(c) is a plan view seen from the bottom side. Note that the lid is omitted from the following plan views seen from the lid side, including FIG. 1(a). Also, for ease of understanding, the dimensional proportions of the components are different from the actual proportions. FIG. 2 is a circuit diagram relating to driving of the crystal resonator including a temperature sensitive element as an electronic element housed in the crystal resonator of the first embodiment.

[0034] As shown in FIG. 1, the quartz crystal resonator 1 includes a quartz crystal resonator piece 10 as a vibrating piece, a thermistor 20 as an example of a temperature-sensing element as an electronic element, and a package 30 in which the quartz crystal resonator piece 10 and the thermistor 20 are housed.

[0035] The quartz crystal vibrating piece 10 is, for example, an AT-cut quartz crystal substrate cut at a predetermined angle from a quartz raw stone or the like, and has a roughly rectangular planar shape and integrally comprises a vibrating portion 11 in which thickness-shear vibration is excited and a base portion 12 connected to the vibrating portion 11. The crystal vibrating piece 10 has extraction electrodes 15a and 16a formed on the base 12, which are extracted from substantially rectangular excitation electrodes 15 and 16 formed on one main surface 13 and the other main surface 14 of the vibrating portion 11.

[0036] The extraction electrode 15a is drawn from the excitation electrode 15 on one of the main surfaces 13 to the base 12 along the longitudinal direction of the quartz vibrating piece 10 (left-right direction on the paper), wraps around to the other main surface 14 along the side of the base 12, and extends to the other main surface 14 of the base 12. The extraction electrode 16a is drawn from the excitation electrode 16 on the other main surface 14 to the base 12 along the longitudinal direction of the quartz vibrating piece 10, wraps around to one main surface 13 along the side of the base 12, and extends to one main surface 13 of the base 12. The excitation electrodes 15, 16 and the extraction electrodes 15a, 16a are made of a metal coating having, for example, a Cr (chromium) base layer on which Au (gold) or a metal containing Au as a main component is laminated.

[0037] The thermistor 20 is, for example, a chip-type (rectangular parallelepiped) temperature-sensitive element (temperature-sensitive resistance element) that has electrodes 21 and 22 at both ends and is a resistor whose electrical resistance changes greatly with temperature changes. For example, a thermistor called an NTC (Negative Temperature Coefficient) thermistor, whose resistance decreases as the temperature rises, is used as the thermistor 20. NTC thermistors are widely used as temperature sensors because the relationship between temperature and change in resistance value is linear. The thermistor 20 is housed in a package 30 and serves as a temperature sensor by detecting the temperature in the vicinity of the quartz crystal resonator element 10, thereby contributing to the correction of frequency fluctuations that accompany temperature changes in the quartz crystal resonator element 10.

[0038] The package 30 has a roughly rectangular, flat planar shape and includes a package base 31 as a substrate having a first main surface 33 and a second main surface 34 that are opposite each other, and a flat lid 32 that covers the first main surface 33 side of the package base 31, and is configured in a roughly rectangular parallelepiped shape. The package base 31 comprises a flat first layer 31a, one of whose surfaces is the first main surface 33; a second layer 31b, which has an opening in the center and is stacked on the side opposite the first main surface 33 of the first layer 31a, with the surface opposite to this stacked surface being the second main surface 34; and a frame-shaped third layer 31c, which is stacked on the first main surface 33 side of the first layer 31a. The first layer 31a and the second layer 31b of the package base 31 are made of ceramic insulating materials such as aluminum oxide sintered body, mullite sintered body, aluminum nitride sintered body, silicon carbide sintered body, and glass ceramic sintered body, which are formed by molding, stacking, and firing ceramic green sheets, or quartz crystal, glass, silicon (high resistance silicon), etc. The third layer 31c of the package base 31 and the lid 32 are made of the same material as the package base 31, or a metal such as Kovar or 42 alloy.

[0039] The first main surface 33 of the package base 31 is provided with internal terminals 33a and 33b at positions facing the extraction electrodes 15a and 16a of the quartz crystal vibrating piece . The extraction electrodes 15a and 16a of the quartz-crystal vibrating piece 10 are bonded to the internal terminals 33a and 33b via a conductive adhesive 40, such as an epoxy, silicone, or polyimide adhesive, that contains a conductive material such as a metal filler. This allows the quartz-crystal vibrating piece 10 to be mounted on the first main surface 33.

[0040] In the quartz crystal resonator 1, the quartz crystal resonator piece 10 is bonded to the internal terminals 33a, 33b of the package base 31, and the third layer 31c of the package base 31 is covered with the lid 32. The package base 31 and the lid 32 are bonded together by seam welding or with a bonding material such as low-melting-point glass or adhesive, thereby hermetically sealing the internal space S formed by the first layer 31a, the third layer 31c of the package base 31, and the lid 32. 1 shows, as an example, a configuration in which the metallic third layer 31c and the metallic 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 hermetically sealed internal space S of the package 30 is in a reduced pressure vacuum state (high degree of vacuum state) or is filled with an inert gas such as nitrogen, helium, or argon.

[0041] A recess 35 is provided on the second main surface 34 side of the package base 31 by the opening of the second layer 31b and the stacking surface of the first layer 31a. The planar shape of the recess 35 is formed, for example, in the shape of a track. Electrode pads 36a and 36b are provided on the bottom surface 36 of the recess 35 (the lamination surface of the first layer 31a) at positions facing the electrodes 21 and 22 of the thermistor 20. The electrodes 21 and 22 of the thermistor 20 are joined to the electrode pads 36a and 36b via a joining member 41 such as a conductive adhesive or solder. The thermistor 20 is disposed in the approximate center of the recess 35 with its longitudinal direction (the direction connecting the electrodes 21 and 22) aligned with the longitudinal direction of the package base 31 (the left-right direction on the paper).

[0042] 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, the two electrode terminals 37b and 37d located at one diagonal corner are connected to internal terminals 33a and 33b connected to extraction electrodes 15a and 16a of the quartz vibrating piece 10, and the remaining two electrode terminals 37a and 37c located at the other diagonal corner are connected to electrode pads 36a and 36b connected to electrodes 21 and 22 of the thermistor 20.

[0043] The four electrode terminals 37a to 37d are formed into a rectangular shape in plan view with a portion cut out on the side of the recess 35. Electrode terminal 37c has a protrusion 38 that extends toward electrode terminal 37b so as to have a larger area than the other electrode terminals 37a, 37b, and 37d in plan view, and the tip of protrusion 38 is formed into a substantially semicircular shape (in other words, the outline of protrusion 38 includes a curve).

[0044] 1(b), when the lid 32 and the third layer 31c of the package base 31 are made of metal, it is preferable from the viewpoint of improving shielding properties that the electrode terminal 37c be electrically connected to the lid 32 via the third layer 31c by either a conductive via (a conductive electrode in which a through-hole is filled with a metal or a conductive material) and internal wiring penetrating the first layer 31a and the second layer 31b of the package base 31, or a conductive film formed in a castellation (recess) (not shown) provided in an outer corner of the package base 31. When the third layer 31c is made of an insulating material, a conductive via is also provided in the third layer 31c. Furthermore, the crystal unit 1 can further improve its shielding properties by grounding the electrode terminal 37c as an earth terminal (GND terminal).

[0045] The internal terminals 33a, 33b, electrode pads 36a, 36b, and electrode terminals 37a to 37d are made of a metal coating formed by laminating coatings of Ni (nickel), Au, etc., on a metallized layer of W (tungsten), Mo (molybdenum), etc., by plating or the like.

[0046] The crystal unit 1 is specified such that the distance L1 in a first direction (thickness direction of the package base 31) perpendicular to the first main surface 33 from the mounting surface (surface for attaching to an external member) of the electrode terminals 37a to 37d to the thermistor 20 is 0.05 mm or more. Furthermore, the crystal unit 1 is specified such that 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 is less than 0.3 mm.

[0047] As an example, the quartz crystal unit 1 uses a material with 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, the thickness of the electrode terminals 37a to 37d is controlled to 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 controlled to 0.02 mm ± 0.01 mm (0.01 mm or more and 0.03 mm or less), the thickness of the bonding member 41 is controlled to 0.01 mm ± 0.005 mm (0.005 mm or more and 0.015 mm or less), and a thin product with a thickness of 0.12 mm ± 0.015 mm (0.105 mm or more and 0.135 mm or less) is used for the thermistor 20. As a result, the distance L1 of the crystal unit 1 is 0.12 mm±0.05 mm (0.07 mm or more and 0.17 mm or less), which is at least 0.07 mm, and therefore fully satisfies the requirement of 0.05 mm or more. Furthermore, the distance L2 of the crystal unit 1 is 0.27 mm±0.02 mm (0.25 mm or more and 0.29 mm or less), and is 0.29 mm at most, so it fully satisfies the regulation of less than 0.3 mm. From these facts, it can be said that the crystal unit 1 satisfies the regulations for the distances L1 and L2 even when tolerances (variations) are taken into consideration, and is therefore fully suitable for mass production.

[0048] Furthermore, the quartz crystal vibrator 1 has a distance L3 in the first direction between a first virtual center line O1 that passes through the center of the thermistor 20 in the first direction and extends along the first main surface 33, and a second virtual center line O2 that passes through the center of the quartz crystal vibrating piece 10 in the first direction and extends along the first main surface 33, which is within the range of 0.18 mm or more and 0.32 mm or less.

[0049] As an example, the quartz crystal resonator 1 uses a material with a thickness of 0.09 mm to 0.11 mm for the first layer 31a of the package base 31, the thickness of the internal terminals 33a and 33b is 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 quartz crystal resonator piece 10 (with the resonant frequency range of approximately 19 to 52 MHz) is 0.032 mm to 0.087 mm, the thickness of the electrode pads 36a and 36b is 0.01 mm to 0.03 mm, the thickness of the bonding member 41 is controlled within the range of 0.005 mm to 0.015 mm, and a thin product is used for the thermistor 20 with a thickness controlled within the range of 0.105 mm to 0.135 mm. As a result, the distance L3 of the crystal unit 1 falls within the range of 0.187 mm to 0.309 mm, which fully satisfies the requirement of 0.18 mm or more and 0.32 mm or less, and even when tolerances are taken into account, the distance L3 requirement is cleared and mass production is possible. In addition, when the quartz crystal vibrating piece 10 is inclined (the closer it is to the first main surface 33 as it moves from the base 12 to the tip on the opposite side), the distance L3 is the distance between the first imaginary center line O1 and the second imaginary center line O2 within the range of the internal terminal 33a (33b) in Figure 1(b) in the left-right direction of the paper.

[0050] As shown in FIG. 2, in the crystal resonator 1, for example, a drive signal is applied from an oscillator circuit 61 integrated in an IC chip 70 of an electronic device via electrode terminals 37b, 37d, causing the crystal resonator piece 10 to excite thickness-shear vibration, causing it to resonate (oscillate) at a predetermined frequency, and outputting a resonance signal (oscillation signal) from the electrode terminals 37b, 37d. At this time, the thermistor 20 of the quartz crystal resonator 1 detects the temperature near the quartz crystal resonator piece 10 as a temperature sensor, converts it into a change in the voltage value supplied from the power supply 62, and outputs it as a detection signal from the electrode terminal 37a.

[0051] The output detection signal is A / D converted by, for example, an A / D conversion circuit 63 integrated in an IC chip 70 of the electronic device, and input to a temperature compensation circuit 64 also integrated in the IC chip 70. Then, the temperature compensation circuit 64 outputs a correction signal based on temperature compensation data to the oscillation circuit 61 in accordance with the input detection signal. The oscillation circuit 61 applies a drive signal corrected based on the input correction signal to the quartz crystal vibrating piece 10, correcting the resonant frequency of the quartz crystal vibrating piece 10, which fluctuates with temperature changes, to a predetermined frequency. The oscillation circuit 61 amplifies the oscillation signal of this corrected frequency and outputs it to the outside.

[0052] As described above, in the crystal resonator 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. In this way, by using a thin thermistor 20 and setting the distance L1 from the mounting surface of the electrode terminals 37a to 37d to the thermistor 20 to 0.05 mm or more, the quartz crystal resonator 1 can promote the flow of air within the recess 35 when mounted on an external component such as an electronic device, thereby reducing the delay in the temperature drop of the thermistor 20 caused by stagnation of air within the recess 35.

[0053] Here, the above content will be described in detail. Fig. 3 is a graph illustrating the relationship between the distance L1 and the temperature change tracking ability of the thermistor when the temperature of the quartz crystal resonator piece changes, and Fig. 4 is a graph illustrating the relationship between the distance L1 and the temperature hysteresis yield of the quartz crystal resonator. The graph in Fig. 3 is based on the analysis results of simulations and experiments by the inventors of the present application. The horizontal axis of Figure 3 represents elapsed time, and the vertical axis represents temperature. The horizontal axis of Figure 4 represents distance L1, and the vertical axis represents the yield of temperature hysteresis of the crystal unit.

[0054] 3, when the distance L1 from the mounting surface of the electrode terminals 37a-37d to the thermistor 20 is 0.05 mm, the temperature change detected by the thermistor 20 follows the temperature change of the quartz crystal vibrating piece 10 with almost no delay, both when the temperature rises and falls. In other words, when the distance L1 is 0.05 mm, there is almost no temperature difference between the temperature of the quartz crystal vibrating piece 10 and the temperature detected by the thermistor 20. In contrast, when the distance L1 is less than 0.05 mm, as the distance L1 decreases to 0.04 mm and 0.03 mm, a delay occurs in the temperature change (temperature drop) detected by the thermistor 20 when the temperature of the quartz crystal vibrating piece 10 drops, and the temperature difference between the temperature of the quartz crystal vibrating piece 10 and the temperature detected by the thermistor 20 increases. This is thought to be because the air stagnates in the recess 35 due to the reduced distance L1, and the insulating effect of the air heated when the temperature rises prevents the temperature of the thermistor 20 from decreasing.

[0055] As a result, as shown in Figure 4, when the distance L1 is 0.05 mm or more, the yield of temperature hysteresis (the difference between the frequency shift when the temperature rises and the frequency shift when the temperature falls) of the crystal unit 1 is 100%. On the other hand, when the distance L1 is less than 0.05 mm, the yield of the thermal hysteresis of the crystal resonator 1 does not reach 100%, and the yield decreases as the distance L1 decreases to 0.04 mm and 0.03 mm. These results show that the temperature difference between the temperature of the quartz crystal vibrating piece 10 and the temperature detected by the thermistor 20 can be reduced by setting the distance L1 to 0.05 mm or more. This allows the crystal unit 1 to have good frequency temperature characteristics.

[0056] Next, the inventors of the present application conducted verification experiments on the ability of the thermistor 20 to follow temperature changes when the temperature of the quartz crystal vibrating piece 10 changes, and the results thereof will be described below. Based on the analysis results of Figures 3 and 4 described above, an experiment was conducted to examine the responsiveness of the temperature detected by the thermistor 20 to the temperature of the quartz crystal vibrating piece 10 at a distance L1 of 0.05 mm, where there was almost no difference in temperature between the temperature of the quartz crystal vibrating piece 10 and the temperature detected by the thermistor 20.

[0057] The quartz crystal resonator 1 according to the first embodiment was mounted on an external substrate, and heat was applied to the external substrate. The temperature detected by the thermistor 20 was compared with the temperature of the quartz crystal resonator piece 10 at that time, and the temperature difference was evaluated. First, the temperature of the external substrate was raised from 29.0°C to 32.0°C. At this time, the thermistor 20 detected the frequency of the quartz crystal vibrating piece 10 at each temperature from 29.5°C to 31.5°C in 0.1°C increments, and the frequency deviation was calculated based on the frequency of the quartz crystal vibrating piece 10 at 29.5°C detected by the thermistor 20 as the reference temperature. Next, the temperature of the external substrate was decreased from 32.0°C to 29.0°C. The frequency of the quartz crystal vibrating piece 10 was measured at each temperature detected by the thermistor 20 in 0.1°C increments from 31.5°C to 29.5°C, and the frequency deviation was calculated based on the frequency of the quartz crystal vibrating piece 10 at 29.5°C detected by the thermistor 20 during temperature increase. These are shown in Table 1 below.

[0058] [Table 1]

[0059] Since the quartz crystal vibrating piece 10 is an AT-cut quartz crystal vibrating piece, its frequency-temperature characteristics exhibit a cubic curve. Based on data on the frequency-temperature characteristics of the quartz crystal vibrating piece 10 that was measured in advance, the inventors calculated the temperature of the quartz crystal vibrating piece 10 from the frequency deviation of the quartz crystal vibrating piece 10 at each temperature detected by the thermistor 20. These are shown in Table 2 below.

[0060] [Table 2]

[0061] Next, the temperature difference between the temperature detected by the thermistor 20 and the temperature of the quartz crystal vibrating piece 10 at each temperature detected by the thermistor 20 was calculated from Table 2. These are shown in Table 3 below.

[0062] [Table 3]

[0063] Figure 5 is a graph showing the temperature difference between the temperature detected by the thermistor and the temperature of the quartz crystal resonator element, 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 quartz crystal resonator element. It was found that the temperature difference dT between the temperature detected by the thermistor 20 and the temperature of the quartz crystal vibrating piece 10 was between -0.07°C and 0.00°C. In other words, from this verification experiment, the tracking ability of the temperature detected by the thermistor 20 to the temperature of the quartz crystal vibrating piece 10 was as follows: It was found that if |dT|≦0.1 (° C.) is satisfied, a resonator device (quartz crystal resonator 1) with good frequency-temperature characteristics can be obtained. Furthermore, the temperature tracking capability |dT|≦0.1 (°C) detected by the thermistor 20 is not limited to the schematic configuration of the quartz crystal resonator 1 of the first embodiment as shown in FIG. 1, but can also be applied to a resonator device equipped with a so-called single-seal type package in which the resonator element and the temperature-sensing element are housed together in a single housing.

[0064] Furthermore, 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 quartz crystal vibrator 1 is less than 0.3 mm, the temperature difference between the temperature of the quartz crystal vibrating piece 10 and the temperature detected by the thermistor 20 can be reduced while also achieving a thinner design. This allows the crystal unit 1 to be thin and have good frequency temperature characteristics.

[0065] Furthermore, since the distance L3 in the first direction between the first imaginary center line O1 of the thermistor 20 and the second imaginary center line O2 of the quartz crystal vibrating piece 10 is within the range of 0.18 mm or more and 0.32 mm or less, the quartz crystal vibrator 1 can be made even thinner while reducing the temperature difference between the temperature of the quartz crystal vibrating piece 10 and the temperature detected by the thermistor 20. If the distance L3 is less than 0.18 mm, the thickness of the first layer 31a of the package base 31 will be thinner than 0.09 mm (assuming that further thinning of the thermistor 20 will be difficult for the time being), and the strength of the package base 31 will become an issue. Furthermore, if the distance L3 exceeds 0.32 mm, the temperature difference between the temperature of the quartz crystal vibrating piece 10 and the temperature detected by the thermistor 20 will increase, deteriorating the frequency-temperature characteristics, which may make it difficult to achieve high accuracy in the quartz crystal vibrator 1.

[0066] Furthermore, of the four electrode terminals 37a to 37d of the quartz crystal resonator 1, the electrode terminal 37c has a protrusion 38 that has a larger area than the other electrode terminals 37a, 37b, and 37d in a planar view, and the tip of the protrusion 38 is formed in an approximately semicircular shape (in other words, the outline of the protrusion 38 includes a curve). As a result, the protrusion 38 of the crystal unit 1 functions as an identification mark for the electrode terminal 37c, and the large area of ​​the electrode terminal 37c serves as a base point, making it easy to bring out the self-alignment effect of the crystal unit 1 (the autonomous positional repair phenomenon that occurs during reflow mounting when the crystal unit 1 is attached to an external substrate via solder).

[0067] Furthermore, since the electronic element of the quartz crystal resonator 1 is a temperature sensitive element, the temperature difference between the temperature of the quartz crystal resonator piece 10 and the temperature detected by the temperature sensitive element can be reduced, while also achieving a thinner design.

[0068] Furthermore, since the temperature-sensing element of the quartz crystal unit 1 is the thermistor 20, the ambient temperature can be accurately detected due to the characteristics of the thermistor 20. Note that a temperature-sensing semiconductor may be used as the temperature-sensing element instead of the thermistor 20, and the ambient temperature can be accurately detected due to the characteristics of the temperature-sensing semiconductor. Examples of the temperature-sensing semiconductor include a diode or a transistor. More specifically, in the case of a diode, the temperature can be 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. In the case of a transistor, the temperature can be detected in the same way as above by shorting the base and collector and making the collector and emitter function as a diode. The crystal unit 1 can reduce noise superposition by using a diode or a transistor as the temperature sensor.

[0069] (Variation) Next, a modification of the first embodiment will be described. Fig. 6 is a schematic diagram showing the general configuration of a quartz crystal resonator according to a modified example of the first embodiment, in which Fig. 6(a) is a plan view seen from the lid side, Fig. 6(b) is a cross-sectional view taken along line AA in Fig. 6(a), and Fig. 6(c) is a plan view seen from the bottom side. The same reference numerals are used to designate parts common to the first embodiment, and detailed explanations thereof will be omitted. The following description will focus on parts that are different from the first embodiment.

[0070] As shown in FIG. 6, the crystal unit 2 of the modified example differs from the first embodiment in the arrangement direction of the thermistor 20. The crystal oscillator 2 is arranged so that the longitudinal direction of the thermistor 20 (the direction connecting the electrodes 21 and 22) intersects (here, perpendicular to) the longitudinal direction of the package base 31 (the left-right direction on the paper).

[0071] As a result, in addition to the effects of the first embodiment, the quartz crystal resonator 2 can reduce the decrease in the fixing strength (bonding strength) of the thermistor 20 that occurs due to warping of the package base 31, which tends to warp significantly in the longitudinal direction. The configuration of the above modified example can also be applied to the following embodiments.

[0072] (Second embodiment) Next, other configurations of the crystal resonator as a resonator device will be described. 7A and 7B are schematic diagrams showing the general configuration of a crystal resonator according to a second embodiment, in which Fig. 7A is a plan view seen from the lid side, Fig. 7B is a cross-sectional view taken along line AA in Fig. 7A, and Fig. 7C is a plan view seen from the bottom side. The same reference numerals are used to designate parts common to the first embodiment, and detailed explanations thereof will be omitted. The following description will focus on parts that are different from the first embodiment.

[0073] As shown in FIG. 7, the crystal unit 3 of the second embodiment differs from the first embodiment in the configuration of the package base 31 and the lid 32. The crystal unit 3 has the third layer 31c of the package base 31 removed, and instead a bonding member 39 for bonding to the lid 32 is disposed. The lid 32 is made of a metal such as Kovar or 42 alloy and is formed in the shape of a cap with a flange 32a provided around the entire periphery. The quartz crystal resonator 3 has an internal space S for accommodating the quartz crystal resonator piece 10 due to the bulge of the cap portion of the lid 32.

[0074] The lid 32 has a flange 32a joined to the first main surface 33 of the package base 31 via a conductive joining member 39 such as a seam ring, brazing material, or conductive adhesive. As a result, the lid 32 is electrically connected to the electrode terminals 37c through the conductive vias and internal wiring in the package base 31, thereby providing a shielding effect. The lid 32 may be electrically connected to the electrode terminal 37c via the bonding member 39 and a conductive film formed on a castellation (not shown) provided on the outer corner of the package base 31.

[0075] As described above, in the crystal resonator 3 of the second embodiment, the third layer 31c of the package base 31 is removed, which makes it easier to manufacture the package base 31 compared to the first embodiment. In addition, as long as there is no problem with shielding, the lid 32 of the crystal unit 3 does not need to be electrically connected to the electrode terminal 37c, and therefore the joining member 39 may be insulating.

[0076] (electronic equipment) Next, a mobile phone will be described as an example of an electronic device equipped with the above-described vibration device. FIG. 8 is a schematic perspective view showing a mobile phone as an electronic device. The mobile phone 700 includes a quartz crystal resonator as a vibration device described in each of the above embodiments and modifications. 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 comprises a liquid crystal display device 701, a plurality of operation buttons 702, an earpiece 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.

[0077] The vibration devices such as the above-mentioned quartz crystal resonators can be suitably used as timing devices for electronic devices including not only the above-mentioned mobile phones, but also e-books, personal computers, televisions, digital still cameras, video cameras, video recorders, navigation devices, pagers, electronic organizers, calculators, word processors, workstations, videophones, POS terminals, game machines, medical devices (e.g., electronic thermometers, blood pressure monitors, blood glucose meters, electrocardiogram measuring devices, ultrasound diagnostic devices, electronic endoscopes), fish finders, various measuring devices, instruments, flight simulators, etc. In any case, the effects described in each of the above embodiments and modified examples can be achieved, and electronic devices with excellent performance can be provided.

[0078] (Mobile) Next, an automobile will be described as an example of a moving object equipped with the above-described vibration device. FIG. 9 is a schematic perspective view showing an automobile as a moving body. The automobile 800 is equipped with a quartz crystal resonator as a vibration device described in each of the above embodiments and modifications. The automobile 800 uses the above-mentioned crystal oscillator (any of 1 to 3) as a timing device such as a reference clock oscillation source for various electronically controlled devices (e.g., an electronically controlled fuel injection device, an electronically controlled ABS device, an electronically controlled constant speed driving device, etc.) installed therein. According to this, the automobile 800 includes the above-mentioned crystal resonator, and therefore the effects explained in the above-mentioned embodiments and modifications are achieved, and excellent performance can be exhibited.

[0079] The above-mentioned vibration devices such as the quartz crystal oscillators can be suitably used as timing devices such as reference clock oscillation sources for moving bodies including not only the above-mentioned automobile 800, but also self-propelled robots, self-propelled conveying equipment, trains, ships, airplanes, artificial satellites, etc. In any case, the effects described in each of the above embodiments and modified examples can be achieved, and a moving body with excellent performance can be provided.

[0080] The shape of the vibrating piece of the quartz crystal resonator is not limited to the flat type shown in the figure, but may be a type that is thick in the center and thin in the periphery (for example, a convex type, a bevel type, or a mesa type), or conversely, a type that is thin in the center and thick in the periphery (for example, an inverted mesa type), or may be a tuning fork shape.

[0081] The material of the vibrating element is not limited to quartz crystal, but may be a piezoelectric material such as lithium tantalate (LiTaO3), lithium tetraborate (Li2B4O7), lithium niobate (LiNbO3), lead zirconate titanate (PZT), zinc oxide (ZnO), or aluminum nitride (AlN), or a semiconductor such as silicon (Si). Furthermore, the thickness-shear vibration may be driven by electrostatic driving using Coulomb force in addition to the piezoelectric effect of the piezoelectric body. [Explanation of symbols]

[0082] 1, 2, 3... quartz crystal resonator as a resonator device, 10... quartz crystal resonator element as a resonator element, 11... vibrating portion, 12... base portion, 13... one main surface, 14... other main surface, 15, 16... excitation electrodes, 15a, 16a... extraction electrodes, 20... thermistor as an example of a temperature-sensitive element as an electronic element, 21, 22... electrodes, 30... package, 31... package base as a substrate, 31a... first layer, 31b... second layer, 31c... third layer, 32... lid, 32a... flange portion, 33... first main surface, 33a, 33b ...internal terminal, 34...second main surface, 35...recess, 36...bottom surface, 36a, 36b...electrode pad, 37a, 37b, 37c, 37d...electrode terminal, 38...protrusion, 39...bonding member, 40...conductive adhesive, 41...bonding member, 61...oscillating circuit, 62...power supply, 63...A / D conversion circuit, 64...temperature compensation circuit, 70...IC chip, 700...mobile phone as electronic device, 701...liquid crystal display device, 702...operation button, 703...earpiece, 704...mouthpiece, 800...automobile as mobile object, S...internal space.

Claims

1. a vibrating element having a central portion with a different thickness from a peripheral portion; a thermistor having electrodes on both ends; The insulating material is made of a ceramic material, and has a first main surface and a second main surface which are opposite each other. and a recessed portion having an opening on the second main surface side and recessed toward the first main surface side, an insulating substrate that is substantially rectangular in plan view; the resonator element is mounted on the first main surface side of the insulating substrate, the recessed portion has a bottom surface and a side surface connecting the opening and the bottom surface, A pair of electrode pads is provided on the bottom surface, The thermistor is disposed in the recess, separated from the side surface, and is located between the both sides in a plan view. One of the electrodes at the end and one of the pair of electrode pads overlap, and the other of the electrodes at both ends the other of the pair of electrode pads is arranged to overlap the other of the pair of electrode pads, The electrodes at both ends and the pair of electrode pads are joined via a joining member, The insulating substrate is provided with electrode terminals at corners of the substantially rectangular shape when viewed from the second main surface side. It is being In a first direction perpendicular to the first main surface from the mounting surface of the electrode terminal to the thermistor The distance between the first and second electrodes is 0.05 mm or more, and a distance in the first direction from the mounting surface of the electrode terminal to the bottom surface of the recess , a vibration device characterized in that the vibration width is less than 0.3 mm.

2. In claim 1, The vibrating element is characterized in that the thickness of the central portion is smaller than the thickness of the peripheral portion. Operating device.

3. In claim 1, The vibrating element is characterized in that the thickness of the peripheral portion is smaller than the thickness of the central portion. Operating device.

4. In claim 1, a first electrode passing through the center of the thermistor in the first direction and extending along the first main surface; a virtual center line passing through the center of the vibrating element in the first direction and extending along the first main surface; The distance in the first direction to the second imaginary center line extending from the first imaginary center line is 0.18 mm or more and 0.32 mm or less. A vibration device characterized by being within the following range.

5. In claim 1, The insulating substrate includes a first substrate portion having the first main surface and the second main surface, and a a frame-shaped second substrate portion disposed on the first main surface and forming a recess having a bottom surface on the first main surface; a hole portion that is disposed on the second main surface side and that forms the recess portion and has the second main surface as a bottom surface; a third substrate portion, The first substrate portion, the second substrate portion, and the third substrate portion are made of the ceramic insulating material. It consists of materials, A vibration device, characterized in that the vibration element is mounted in the recess.

6. In claim 5, The recess has a dimension in a second direction along a long side of the substantially rectangular shape larger than that of the recess. A vibration device characterized by:

7. In claim 1, The opening of the recess has a dimension in a second direction along a long side of the approximately rectangular shape. The vibration device is characterized in that the dimension in the third direction along the short side of the shape is larger than the dimension in the third direction along the short side of the shape. Vice.

8. In claim 1, The opening of the recess has a dimension in a second direction along a long side of the approximately rectangular shape. The vibration device is characterized in that the dimension in the third direction along the short side of the shape is smaller than the dimension in the third direction along the short side of the shape. Vice.

9. A vibration device according to any one of claims 1 to 8, Electronic devices.

10. A vibration device according to any one of claims 1 to 8, A moving object.

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