JP2013070224A - Container, vibration device and electronic apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a small-sized piezoelectric device of a surface mounting type which enables a temperature compensation type oscillator having small frequency drift characteristics.SOLUTION: A container 20A comprises: an insulation substrate 20a having first electrode pads 28a and 28b for a piezoelectric vibration element and second electrode pads 29a and 29b for an electronic element on a front portion and a plurality of mounting terminals 22 on a rear portion; and a lid member 38 for hermetically sealing a space of the front portion. The mounting terminals 22 and the first and second electrode pads 28a, 28b, 29a and 29b are electrically connected by wiring conductors 23b and 23c, respectively. Thermal conductivity Tc of a material substantially constituting the insulation substrate 20a falls within a range satisfying an expression of 50[W/(m K)]≤Tc≤200[W/(m K)].

Description

  The present invention relates to an electronic component container and a piezoelectric device in which an electronic component and a piezoelectric vibration element are mounted on the container. The present invention also relates to a piezoelectric module using the piezoelectric device and an electronic apparatus.

  Patent Documents 1 to 4 disclose temperature compensated piezoelectric oscillators used for wireless communication devices such as mobile phones. Patent Document 4 discloses a temperature-compensated piezoelectric oscillator in which a frequency drift after power-on is reduced using a circuit having a temperature-related fourth-order component or more as a temperature compensation circuit. The IC component used for this has a temperature sensor for sensing temperature, a temperature compensation circuit for compensating for frequency fluctuations due to temperature changes of the piezoelectric vibration element, a variable capacitance element, an amplifier circuit, and the like. It is disclosed that the temperature of the piezoelectric vibration element can be compensated with high accuracy. In addition, the mounting terminals, the element mounting pads, and the IC mounting pads are provided between via electrodes (conductors in which through-holes (via holes) are filled with via electrode paste) provided in the insulating substrate of the container (package) and between the insulating substrates. It is electrically connected by the arranged wiring pattern or the like.

Patent Document 5 discloses an example in which a metal film or the like is fired on a castellation provided at a corner of an insulating container, and this conductive film (castellation electrode) is used as a means for electrical conduction between a mounting terminal and an element mounting pad. It is disclosed. The castellation extending vertically in the four corners of the insulating container is used when a large number of containers are divided into individual containers from a laminated mother wafer formed in a matrix.
An electromagnetic shielding effect can be obtained by connecting one end of a via electrode formed inside the container to a lid member (lid) and connecting the other end to a grounding mounting terminal. Further, by connecting the fired wiring pattern and the castellation electrode between the layers of the container, the mounting terminal and the wiring pattern can be electrically connected. An example is also disclosed in which the castellation electrodes are made conductive by a wiring pattern fired between layers. Tungsten or the like is used for an electrode material such as a wiring pattern.

  By the way, in the above temperature compensated piezoelectric oscillator, there is a slight temperature difference between the temperature of the piezoelectric vibration element in the package and the temperature detected by the temperature sensor built in the IC component provided outside the insulating container. If there is a temperature difference between the two, the frequency temperature characteristic of the piezoelectric vibrator is compensated based on the temperature having an error, so that there is a problem that high-precision temperature compensation cannot be performed and frequency drift occurs. Therefore, in order to deal with such problems, attempts have been made to accurately measure the temperature of the insulating substrate on which the piezoelectric vibration element is mounted.

  In Patent Documents 6 to 8, in order to improve the temperature detection accuracy and reduce the size, a piezoelectric vibration element is accommodated in the upper cavity of the container, and an oscillation circuit is disposed in the lower cavity on the opposite side. A surface mount piezoelectric oscillator having a structure containing a temperature compensation circuit and the like is disclosed. In Patent Document 6, a temperature sensor is disposed in the vicinity of a pad to which a piezoelectric vibration element is connected, and the temperature difference between the temperature of the piezoelectric vibration element and the temperature detected by the temperature sensor is reduced, whereby the frequency temperature characteristics, the frequency It is disclosed that the drift characteristic can be stabilized. However, since the terminal of the IC component connected to the pad for mounting the piezoelectric vibration element is disposed in the vicinity of the amplifier of the oscillation circuit, heat is generated with the operation of the amplifier. As a result, even if a temperature sensor built in the IC component is brought close to the piezoelectric vibration element side, the heat generation temperature of the IC component may be detected, and there is a problem that the frequency drift characteristic is deteriorated.

Next, in Patent Document 7, a piezoelectric vibration element, a first IC component including an oscillation circuit and a temperature sensor are accommodated in the upper cavity of the container, and a temperature compensation circuit is provided in the lower cavity. Further, it is disclosed that by accommodating the second IC component, the piezoelectric vibration element and the temperature sensor can be arranged in the same temperature environment, and the frequency temperature characteristic and the frequency drift characteristic can be stabilized. However, the structure in which the IC component is divided into two parts and the first IC component with the temperature sensor is accommodated in the same cavity as the piezoelectric vibration element is high in cost and low in feasibility, and goes against the downsizing of the entire oscillator. There is a problem.
Further, Patent Document 8 discloses a pillow member in which a piezoelectric vibration element is housed in a cantilever-supported state in an upper recess of a container, an IC component is housed in a lower recess, and a temperature sensor terminal of the IC component is provided in the upper recess. It is disclosed that the frequency temperature characteristic and the frequency drift characteristic can be stabilized by reducing the temperature difference between the temperature of the piezoelectric vibration element and the temperature detected by the temperature sensor.

  However, since any of the structures disclosed in Patent Documents 6 to 8 has a structure in which the piezoelectric vibration element is mounted on the ceramic substrate, the temperature of the ceramic substrate connected to the piezoelectric vibration element via the conductive adhesive is not limited. Is measured, it is estimated that the temperature of the piezoelectric vibration element can be accurately detected. However, in practice, the effect of improving the frequency drift characteristic has not been sufficient. As described above, in the conventional surface mount piezoelectric oscillator in which the IC component including the temperature sensor is arranged apart from the piezoelectric vibration element, the temperature of the piezoelectric vibration element cannot be accurately detected, and a stable frequency temperature characteristic is obtained. I can't get it. Further, there has been a problem that the frequency drift characteristic at the time of start-up is insufficient.

  Patent Document 9 discloses a surface-mount piezoelectric oscillator in which an IC chip is bonded to the main surface of a container of a piezoelectric vibrator. The IC chip incorporates a temperature sensor, and the piezoelectric vibration element is accommodated in the container. The frequency of the piezoelectric vibration element varies with a temperature change, and the output signal of the temperature sensor changes with a temperature change. A piezoelectric oscillator is constituted by the oscillation circuit built in the IC chip and the piezoelectric vibration element, and the frequency of the piezoelectric oscillator is compensated by the temperature compensation circuit built in the IC chip. In other words, the temperature compensated oscillation circuit outputs a voltage signal for temperature compensation based on the output signal from the temperature sensor, and changes the capacitance of the variable capacitance element by applying it to the variable capacitance element to compensate the frequency. To do. Although the vibration frequency of the piezoelectric vibration element fluctuates due to the change in temperature, the temperature compensation oscillation circuit operates by the output signal of the temperature sensor to compensate for the change in frequency. It is described that the temperature difference can be reduced by fixing the IC chip to the container of the piezoelectric vibrator to bring the positions of the two close together. It is disclosed that the temperature sensor is formed on the surface layer portion of the IC chip, and the frequency temperature characteristic and the frequency drift characteristic can be stabilized by configuring the oscillator in such a configuration.

  Recently, with respect to the main circuit boards of mobile phones, technological innovations such as integration and chipset advance have progressed, and the trend of miniaturization, low profile, and fewer parts is remarkable. That is, the temperature-compensated piezoelectric oscillator described in Patent Documents 1 to 9 is not necessarily required, and there is a tendency to add a temperature compensation circuit to an IC component mounted on the main circuit board (motherboard). is there. However, an attempt has been made to realize temperature compensation of the piezoelectric vibrator by using a piezoelectric vibrator as the reference frequency source and combining the piezoelectric vibrator with the IC component (chip set) as described above.

However, there is a problem that there is a temperature difference between the temperature of the piezoelectric vibrator mounted on the main circuit board and the output temperature of the temperature sensor that detects the temperature of the piezoelectric vibrator. This has been clarified by arranging a piezoelectric vibrator, a temperature sensor, and a heat source on a circuit board and obtaining a temperature distribution on the circuit board by simulation. A slight temperature difference between the piezoelectric vibrator and the temperature sensor affects the position measurement accuracy of the GPS mounted on the mobile phone. This is because the short-term stability of the reference frequency is an extremely important factor for GPS.
In Patent Document 10, a rectangular container having a recess made of a bottom plate and a frame wall, a crystal resonator element housed in the container, a metal cover joined to an opening of the container, and a temperature detector for the crystal resonator element And a thermistor attached to one end side in the longitudinal direction of the container. This is a crystal resonator with a temperature sensor in which the longitudinal direction of the thermistor is fixed to the outer surface of the container perpendicular to the height direction of the container.
In Patent Document 11, a container made of a concave laminated ceramic having a bottom plate layer and a frame wall layer, a crystal resonator element housed in the container and fixed at both ends at one end, and a container together with the crystal resonator element were housed in the container. A surface-mounted crystal resonator including a thermistor is disclosed. The main surface of the crystal resonator element faces the uppermost layer of the bottom plate layer, and the thermistor is a crystal resonator with a temperature sensor configured to be disposed in a recess provided in the bottom plate layer.

Japanese Patent Laid-Open No. 2005-217784 JP 2005-244925 A JP 2009-089437 A JP 2010-206443 A JP 2006-054314 A JP 2006-191517 A JP 2008-263564 A JP 2010-035078 A JP 2009-105199 A JP 2010-118979 A JP 2008-205938 A

However, in the above-described piezoelectric device, the first storage portion that stores the piezoelectric vibration element has a structure in which the temperature-sensitive component (thermistor) is mounted on the second storage portion on the opposite side via the bottom portion (made of ceramic). Since the container is made of an insulating ceramic, between the temperature of the piezoelectric vibration element in the first storage portion and the temperature detected by the temperature sensitive component in the second storage portion from the viewpoint of thermal conductivity. There was a problem that a temperature difference occurred.
In the structure disclosed in Patent Document 11, it is expected that the thermistor is mounted inside the container of the piezoelectric vibrator and the temperature of the piezoelectric vibration element can be detected. However, when some characteristic failure occurs in the piezoelectric vibration element accommodated in the container, the thermistor mounted in the same container must be discarded, and there is a problem that the cost increases accordingly.
Further, in the structure disclosed in Patent Document 10, the structure of the container is simplified and the cost can be reduced, but it is difficult to configure a piezoelectric oscillator having the performance required for the GPS function of the mobile phone in combination with an external circuit. . In other words, a temperature difference occurs between the actual temperature of the piezoelectric vibration element and the temperature detected by the thermistor (temperature-sensitive component) in a short time after the power is turned on, and the standard required by the GPS function cannot be satisfied. There was a problem.
The present invention has been made in view of the above, and by making the temperature difference between the temperature of the piezoelectric vibration element and the temperature sensitive element as small as possible, in combination with a compensation circuit mounted on the main circuit board (motherboard), It is an object of the present invention to provide a small surface-mount piezoelectric device that has a small frequency drift characteristic and enables a temperature compensated oscillator.

  SUMMARY An advantage of some aspects of the invention is to solve at least a part of the problems described above, and the invention can be implemented as the following forms or application examples.

  Application Example 1 A container according to the present invention includes a first electrode pad on which a vibration element is mounted on a first main surface side, and a second electrode pad on which an electronic element is mounted. An insulating substrate having a plurality of mounting terminals on the second main surface side opposite to the main surface, and the space on the first main surface side including the vibration element and the electronic element are hermetically sealed. A mounting member, and the mounting terminal and the first and second electrode pads are electrically connected to each other by a wiring conductor, and heat conduction of a material mainly constituting the insulating substrate. The container is characterized in that the rate Tc satisfies 50 [W / (m · K)] ≦ Tc ≦ 200 [W / (m · K)].

  According to this configuration, since the material constituting the insulating substrate has high thermal conductivity, the heat conducted from the mounting terminal is transmitted three-dimensionally through the insulating substrate at the same time as the wiring conductor, and the first and second There is an effect that the temperature rise curve with respect to the time of each electrode pad becomes almost the same curve. Moreover, since the structure of a container is simple, there exists an advantage that cost can be reduced.

  [Application Example 2] The container according to Application Example 1, wherein the container is provided with a seal ring at the periphery of the first main surface of the insulating substrate.

  According to this structure, since the lid member welded to the seal ring and the mounting terminal for grounding are conductively connected, there is an effect that the container has a shielding effect.

  Application Example 3 In addition, the container includes a first electrode pad on which a vibration element is mounted on the first main surface side, and a second electrode pad on which an electronic element is mounted. The first main surface A first insulating substrate having a plurality of mounting terminals on the second main surface side opposite to the first main surface of the first insulating substrate. And a lid member that hermetically seals the space including the electronic element and the vibration element positioned in the hollow portion of the second insulating substrate, the mounting terminal, The first and second electrode pads are electrically connected to each other by a wiring conductor, and the thermal conductivity Tc of a material mainly constituting the insulating substrate is 50 [W / (m · K)] ≦ Tc. ≦ 200 [W / (m · K)] is satisfied.

  According to this configuration, since the container is configured by laminating and firing the first and second insulating substrates having high thermal conductivity, heat conducted from the mounting terminal is transmitted through the wiring conductor and at the same time, the inside of the insulating substrate. There is an effect that the temperature rise curves with respect to the time of the first and second electrode pads are substantially similar curves.

  Application Example 4 In addition, the container includes a first electrode pad on which the vibration element is mounted on the first main surface side, and an electronic element on the second main surface side opposite to the first main surface side. A first insulating substrate having a second electrode pad on which the first insulating substrate is mounted, and a bottom portion is laminated and fixed to the first main surface of the first insulating substrate to form a first accommodating portion. An annular second insulating substrate and a second housing portion are formed by laminating and fixing a front portion to the second main surface side, and an annular third insulating member having a plurality of mounting terminals at the bottom. An insulating substrate; and a lid member that hermetically seals the space including the vibration element located in the hollow portion of the second insulating substrate, and the mounting terminal and the first and second electrode pads are: Thermal conduction of materials that are electrically connected by respective wiring conductors and that mainly constitute the first, second, and third insulating substrates. Tc is a container that satisfies the 50 [W / (m · K)] ≦ Tc ≦ 200 [W / (m · K)].

  According to this configuration, since the container is configured by laminating and firing the first, second, and third insulating substrates having high thermal conductivity, the heat conducted from the mounting terminal is transmitted through the wiring conductor and at the same time is insulated. There is an effect that the temperature rise curves with respect to the time of the first and second electrode pads become substantially similar curves in a three-dimensional manner in the substrate. Moreover, since the 1st accommodating part and the 2nd accommodating part are isolate | separated by the 1st insulating substrate, there exists an advantage that it is suitable for the vibration device etc. which require high precision and high stability.

  Application Example 5 In the application example 1, the container satisfies the thermal conductivity Tc of 120 [W / (m · K)] ≦ Tc ≦ 200 [W / (m · K)]. It is a container as described in any one of thru | or 4.

  According to this configuration, there is an effect that the temperature rise curves with respect to the respective times of the first and second electrode pads become closer curves.

  Application Example 6 Further, the container is the container according to any one of Application Examples 1 to 4, wherein the thermal conductivity Tc is equal to the thermal conductivity of the wiring conductor.

  According to this configuration, by arranging the first and second electrode pads so as to be equidistant from the mounting terminals, there is an effect that the temperature rise curves with respect to time become substantially similar curves.

  Application Example 7 A vibration device according to the present invention is a vibration device in which a vibration element and an electronic element are mounted on the container according to any one of Application Examples 1 to 6.

  According to this configuration, since the vibrating device is configured using the container according to the present invention, the temperature rise curves with respect to time of the vibrating element and the electronic element for detecting the temperature thereof are substantially the same, so that the external oscillator And a compensation circuit can be accurately compensated, and a reference oscillator having a small frequency drift characteristic can be configured.

  Application Example 8 In the vibration device, the lid member is electrically connected to the mounting terminal by a conductor penetrating the inside of the container or a castellation electrode provided on an outer surface of the container. It is a vibration device as described in application example 7 characterized by these.

  According to this configuration, since the grounding mounting terminal and the lid member are conductively connected, there is an effect that a vibrating device having a shielding effect can be configured.

  [Application Example 9] The vibration device according to Application Example 7 or 8, wherein the vibration element is a tuning fork type crystal vibration element.

  According to this configuration, since a tuning fork type crystal resonator element is used as the resonator element, there is an advantage that a desired low frequency reference oscillator can be obtained without requiring a circuit for dividing a high frequency.

  Application Example 10 Further, in the vibration device, the substrate of the vibration element includes an X axis as an electric axis that is a crystal axis of quartz, a Y axis as a mechanical axis, and a Z axis as an optical axis. Centering on the X axis of the coordinate system, the Z axis is inclined by a predetermined angle in the −Y direction of the Y axis as a Z ′ axis, and the Y axis is in the + Z direction of the Z axis. A quartz substrate that is formed by a plane parallel to the X-axis and the Z′-axis, with the axis tilted only by the Y′-axis and having a thickness in a direction parallel to the Y′-axis, and a side parallel to the X-axis The vibration device according to Application Example 7 or 8, wherein a quartz substrate having a long side and a short side parallel to the Z ′ axis is used.

According to this structure, there exists an effect that the temperature characteristic which a customer specification requires can be implement | achieved appropriately.

  Application Example 11 In the application example 7 or 8, the vibration device includes an AT-cut crystal vibration element and a tuning-fork crystal vibration element disposed in the housing portion as the vibration element. It is a vibration device.

  According to this configuration, an AT-cut crystal resonator element and a tuning-fork crystal resonator element are used, and two temperature compensated piezoelectric elements of high frequency and low frequency are used in combination with an external oscillation circuit and a compensation circuit. An oscillator is configured, and two reference frequencies having excellent frequency drift characteristics can be obtained.

  Application Example 12 An electronic apparatus according to the present invention is an electronic apparatus including the vibration device according to any one of Application Examples 7 to 11.

  When an electronic device is manufactured using the above-described vibration device, there is an effect that a reference frequency source having high stability and excellent frequency drift characteristics can be easily configured.

BRIEF DESCRIPTION OF THE DRAWINGS It is the schematic of the container which concerns on the 1st Embodiment of this invention, (a) is the perspective view which abbreviate | omitted the lid member, (b) is the top view which abbreviate | omitted the lid member, (c) is Q- of (b). Q sectional drawing, (d) is a bottom view. (A) And (b) is a figure which shows the modification of the electrode pattern of the surface of an insulating substrate, and a back surface. The container which concerns on the 2nd Embodiment of this invention, (a) is the perspective view which abbreviate | omitted the lid member, (b) is the top view which abbreviate | omitted the lid member, (c) is QQ sectional drawing of (b). , (D) is a bottom view. The container which concerns on the 3rd Embodiment of this invention, (a) is the top view which abbreviate | omitted the cover member, (b) is QQ sectional drawing of (a), (c) is a bottom view. BRIEF DESCRIPTION OF THE DRAWINGS It is the schematic of the piezoelectric device which concerns on the 1st Embodiment of this invention, (a) is the top view which abbreviate | omitted the cover member, (b) is QQ sectional drawing of (a), (c) is a bottom view. It is the schematic of the piezoelectric device 2, (a) is the top view which abbreviate | omitted the cover member, (b) is QQ sectional drawing of (a), (c) is a bottom view. The figure explaining a coordinate axis and a cutting angle. (A) is a top view of a piezoelectric vibration element, (b) is QQ sectional drawing. (A) is a figure explaining the heat conduction of the piezoelectric device 2, (b) is a table | surface explaining the heat conductivity of a member. (A) is a figure which shows the relationship between the elapsed time of the piezoelectric device 2 of this invention, and each temperature of a piezoelectric vibration element and a thermosensitive element, (b) is the elapsed time and piezoelectricity of the conventional piezoelectric device. It is a figure which shows the relationship with each temperature of a vibration element and a temperature sensing element, (c) is the thermal conductivity when the thermal conductivity of the container is changed, and the temperature difference between the piezoelectric vibration element and the temperature sensing element. FIG. It is the schematic of the piezoelectric device 3, (a) is the top view which abbreviate | omitted the cover member, (b) is QQ sectional drawing of (a), (c) is a bottom view. It is the schematic of the piezoelectric device 4, (a) is the top view which abbreviate | omitted the cover member, (b) is QQ sectional drawing of (a), (c) is a bottom view. It is the schematic of the piezoelectric device 5, (a) is the top view which abbreviate | omitted the cover member, (b) is QQ sectional drawing of (a), (c) is a bottom view. It is the schematic of the piezoelectric device 6, (a) is sectional drawing, (b) is a top view of the container which abbreviate | omitted the cover member, (c) is QQ sectional drawing of (b). The block diagram which shows the structure of a digital mobile telephone. FIG. 3 is a cross-sectional view showing a configuration of a piezoelectric device 7. The structure of a tuning fork type piezoelectric vibration element is shown, (a) is a top view, (b) is PP sectional drawing of (a). It is the schematic which shows the structure of the piezoelectric device 8, (a) is a top view except the cover member, (b) is QQ sectional drawing of (a).

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a schematic diagram showing the configuration of an electronic component container 20A according to an embodiment of the present invention. FIG. 1 (a) is a perspective view in which a lid member 38 is omitted, and FIG. It is the top view which omitted the cover member 38, the figure (c) is QQ sectional drawing of (b), and the figure (d) is a bottom view of container 20A.
The container 20 </ b> A of the present invention is configured by roughly including an insulating substrate 20 a and a lid member 38. As a material of the insulating substrate 20a, the thermal conductivity of ordinary alumina ceramic (Al ₂ O ₃ ) is larger than 17 [W / (m · K)], for example, 50 [W / (m · K)] ≦ Tc ≦ 200. The ceramic material is [W / (m · K)]. As an example, silicon carbide (SiC, 60 [W / (m · K)] to 200 [W / (m · K)]), aluminum nitride (AlN, 120 [W / (m · K)] to 160 [W / (M · K)]) and the like.
The lid member 38 may be a metal plate pressed into a bathtub shape (inverted bowl shape), or may be a ceramic, glass or the like formed into a concave shape.

As shown in FIG. 1 (b), a pair of piezoelectric vibration elements are mounted along the short direction near one end in the longitudinal direction of the first main surface (front portion) S1 of the insulating substrate 20a. First electrode pads 28a and 28b are provided, and a pair of second electrode pads 29a and 29b for mounting electronic elements along the short direction are provided near the other end. Further, as shown in FIG. 1D, a plurality of mounting terminals 22 (22a to 22d) are provided at the corners of the second main surface S2 opposite to the first main surface S1. Yes.
A via electrode (a conductor formed by filling a via hole (through hole) with a via electrode paste and firing) is formed inside the insulator of the insulating substrate 20a. As shown in FIGS. 1C and 1D, the mounting terminals 22a and 22b formed on the second main surface (back surface) S2 and the first main surface (front surface) are formed inside the thickness of the insulating substrate 20a. Part) Via electrodes 23a and 23b are formed to penetrate through the pair of first electrode pads 28a and 28b for the piezoelectric vibration element formed in S1. Also, mounting terminals 22c and 22d formed on the second main surface (back surface) S2, and a pair of second electrode pads 29a and 29b for electronic elements formed on the first main surface (front portion) S1. And via electrodes 24a and 24b are formed to pass through. In addition, castellations C1, C2, C3, and C4 are formed on the side wall surfaces at the corners of the insulating substrate 20a.

For example, a low-melting glass material is applied to the peripheral edge portion of the first main surface (front portion) S1 of the insulating substrate 20a, and the outer peripheral skirt portion of the concave cover member 38 made of metal or nonmetal on the glass material. The glass material is heated and welded to seal the space on the first main surface S1. Further, in the step of forming the first and second electrode pads 28a, 28b, 29a, 29b on the peripheral portion of the first main surface (front portion) S1 of the insulating substrate 20a, a seal ring is screen-printed. If it is fired, an insulating substrate 20a having a seal ring at the peripheral edge can be formed.
A metal lid member 38 is placed on the seal ring, and the space on the first main surface S1 can be sealed by resistance welding or the like. When a seal ring is provided on the peripheral edge of the first main surface S1, a via electrode is formed to electrically connect the seal ring and the grounding mounting terminal 22, and the metal lid member 38 is grounded. Can have a shielding effect.

  FIG. 2 is a diagram showing a configuration of an insulating substrate 20a1 that is a modification of the insulating substrate 20a shown in FIG. 1, and FIG. 2 (a) is a diagram showing an electrode pattern on the first main surface (front portion). FIG. 6B is a diagram showing an electrode pattern on the second main surface (back portion). A metal film is fired on the wall surfaces of castellations C1 to C4 provided at the corners of the insulating substrate 20a1 to form castellation electrodes Ce1 to Ce4. The castellation electrodes Ce1 and Ce2 are electrically connected to the mounting terminals 22a and 22b, respectively, and the first electrode pads 28a for mounting the piezoelectric vibration element are formed by the wiring patterns 26a and 26a formed on the first main surface S1. , 28b are electrically connected. Further, the castellation electrodes Ce3 and Ce4 are electrically connected to the mounting terminals 22c and 22d, respectively, and the second wiring patterns 26b and 26b formed on the first main surface S1 are used to mount second electronic elements. The electrode pads 29a and 29b are also conductively connected.

3A and 3B are views showing the configuration of the container 20B of the second embodiment. FIG. 3A is a perspective view in which the lid member 38 is omitted, and FIG. 3B is a plan view in which the lid member 38 is omitted. (C) is a cross-sectional view taken along the line Q-Q in (b), and (d) is a bottom view.
As shown in FIG. 3C, the container 20 </ b> B schematically includes a flat plate-like first insulating substrate 20 a 1, a rectangular annular second insulating substrate 20 b 1, and a flat plate-like lid member 38. The first insulating substrate 20a1 includes first electrode pads 28a and 28b on which piezoelectric vibration elements are mounted along the short side direction near one end in the longitudinal direction of the first main surface (front portion) S1. ing. Furthermore, the first insulating substrate 20a1 includes a pair of second electrode pads 29a and 29b for mounting electronic elements along the short direction near the other end, and the first main surface S1 is A plurality of mounting terminals 22 (22a, 22b, 22c, 22d) are provided on the opposite second main surface S2 side.

The second insulating substrate 20b1 is an annular insulating substrate whose bottom is stacked and fixed to the first main surface (front portion) S1 of the first insulating substrate 20a1. A recess formed by the annular hollow portion of the second insulating substrate 20b1 and the first main surface S1 of the first insulating substrate 20a1 is a housing portion 27 that houses the piezoelectric vibration element and the electronic element. An annular seal ring 42 is fired around the upper periphery of the second insulating substrate 20b1. A metal lid member 38 is welded to the seal ring 42 to hermetically seal the accommodating portion 27.
As shown in FIGS. 3C and 3D, the mounting terminals 22a and 22b formed on the second main surface (rear surface) S2 and the first main substrate are formed inside the thickness of the first insulating substrate 20a1. Via electrodes 23a and 23b are formed penetratingly connecting the pair of first electrode pads 28a and 28b for the piezoelectric vibration element formed on the surface (surface portion) S1. Also, mounting terminals 22c and 22d formed on the second main surface (back surface) S2, and a pair of second electrode pads 29a and 29b for electronic elements formed on the first main surface (front portion) S1. And via electrodes 24a and 24b are formed to pass through.

Castoration electrodes Ce1 to Ce4 are formed at corners of the container 20B. As in FIG. 2, the castellation electrodes Ce1 and Ce2 are electrically connected to the mounting terminals 22a and 22b, respectively, and the piezoelectric vibration element mounting is provided by the wiring patterns 26a and 26a formed on the first main surface S1. The first electrode pads 28a and 28b are also conductively connected to each other. The castellation electrodes Ce3 and Ce4 are electrically connected to the mounting terminals 22c and 22d, respectively, and the second wiring patterns 26b and 26b formed on the first main surface S1 are second electrodes for mounting electronic elements. The pads 29a and 29b are electrically connected to each other. Further, the seal ring 42 formed on the upper peripheral edge of the second insulating substrate 20b1 and the grounding mounting terminal 22c are electrically connected by the via electrode 25 penetrating the first insulating substrate 20a1 and the second insulating substrate 20b1. It is connected.
The first and second insulating substrates 20a1 and 20b1 of the container 20B have high thermal conductivity Tc (50 [W / (m · K)] ≦ Tc ≦ such as silicon carbide (SiC) and aluminum nitride (AlN). 200 [W / (m · K)]).

FIG. 4 is a diagram showing the configuration of the container 20C of the third embodiment, in which FIG. 4 (a) is a plan view in which the lid member 38 is omitted, and FIG. 4 (b) is a diagram of QQ in FIG. It is sectional drawing and the figure (c) is a bottom view. As shown in FIG. 4B, the container 20C is roughly provided with a first insulating substrate 20a2, a second insulating substrate 20b2, a third insulating substrate 20c2, and a flat lid member 38. . The first insulating substrate 20a2 has first electrode pads 28a, 28b on which piezoelectric vibration elements are mounted along the short direction, near one end in the longitudinal direction of the first main surface (front portion) S1. I have. Furthermore, a pair of second electrode pads 29a and 29b for mounting electronic elements are provided in the center of the second main surface S2 opposite to the first main surface S1.
The second insulating substrate 20b2 is an annular flat insulating substrate, the bottom of which is laminated and fixed to the first main surface S1 of the first insulating substrate 20a2, and the first accommodating portion 27a for the piezoelectric vibration element. Form. A seal ring 42 is formed on the upper peripheral edge of the second insulating substrate 20b2.
The third insulating substrate 20c2 is an annular flat insulating substrate, and a surface portion is laminated and fixed to the second main surface S2 of the first insulating substrate 20a2, so that a second accommodating portion 27b for an electronic element is formed. Form. A plurality of mounting terminals 22 (22a, 22b, 22c, 22d) are formed on the bottom of the third insulating substrate 20c2. The first accommodating portion 27 a is hermetically sealed by the lid member 38.

  As shown in FIG. 4, via electrodes 23 c and 23 d that are electrically connected to one end of the first electrode pads 28 a and 28 b on the first main surface S <b> 1 are formed inside the thickness of the first insulating substrate 20 a 2. ing. Furthermore, wiring patterns 26a and 26a that are conductively connected to the other ends of the via electrodes 23c and 23d are formed, and wiring patterns 26b and 26b that are conductively connected to the second electrode pads 29a and 29b of the second main surface S2 are formed. Is formed. Via electrodes 23a and 23b that are electrically connected to one end of the mounting terminals 22a and 22b are formed inside the third insulating substrate 20c2. The other ends of the via electrodes 23a and 23b are electrically connected to the other ends of the wiring patterns 26a and 26a, respectively. In addition, via electrodes 24b and 24a whose one ends are electrically connected to the mounting terminals 22c and 22d are formed inside the thickness of the third insulating substrate 20c2, and the other ends are the second main terminals of the first insulating substrate 20a2. The other ends of the wiring patterns 26b and 26b formed on the surface S2 are electrically connected. A via electrode 25 penetrating the first, second, and third insulating substrates 20a2, 20b2, and 20c2 is provided, and a seal ring 42 formed on the upper peripheral edge of the grounding mounting terminal 22c and the second insulating substrate 20b2. Are connected to each other. Castoration electrodes Ce1, Ce2, Ce3, and Ce4 are formed on the sidewalls of the corner portions of the first insulating substrate 20a2, the second insulating substrate 20b2, and the third insulating substrate 20c2, respectively. Patterns for conductively connecting 22a, 22b, 22c, and 22d are provided. The first, second, and third insulating substrates 20a2, 202, and 20c2 have high thermal conductivity (50 [W / (m · K)] ≦ Tc such as silicon carbide (SiC) and aluminum nitride (AlN). ≦ 200 [W / (m · K)]).

As shown in the embodiment of FIG. 1, the material constituting the insulating substrate 20a of the container 20A has a high thermal conductivity (50 [W / (m · K)] ≦ Tc ≦ 200 [W / (m · K)]). Therefore, the heat conducted from the mounting terminal 22 is transmitted through the wiring conductor (via electrodes 23a to 23d) and at the same time three-dimensionally in the insulating substrate, and the first and second electrode pads 28a, 28b, 29a, 29b. There is an effect that the temperature rise curve with respect to each time becomes substantially the same curve. Moreover, since the structure of a container is simple, there exists an advantage that cost can be reduced.
Since the seal ring is provided on the periphery of the first main surface of the insulating substrate 20a shown in FIG. 1, and the lid member 38 welded to the seal ring and the mounting terminal 22c for grounding are electrically connected, the container has a shielding effect. There is an effect of having.
As shown in the embodiment of FIG. 3, the container 20 </ b> B has a first and second containers having high thermal conductivity (50 [W / (m · K)] ≦ Tc ≦ 200 [W / (m · K)]). Since the insulating substrates 20a1 and 20b1 are laminated and fired, the heat conducted from the mounting terminal 22 is transmitted three-dimensionally through the first and second insulating substrates at the same time as being transmitted through the wiring conductors 23a to 23d. , And the second electrode pads 28a, 28b, 29a, 29b have an effect that the temperature rise curves with respect to the respective times become substantially similar curves.

As shown in the embodiment of FIG. 4, the container 20C has first, second, and high thermal conductivity (50 [W / (m · K)] ≦ Tc ≦ 200 [W / (m · K)]). Since the third insulating substrates 20a2, 20b2, and 20c2 are laminated and fired, the heat conducted from the mounting terminal 22 is transmitted through the wiring conductors 23a to 23d and at the same time three-dimensionally in the insulating substrate. Also, there is an effect that the temperature rise curves with respect to the respective times of the second electrode pads 28a, 28b, 29a, 29b become substantially similar curves. Moreover, since the 1st accommodating part 27a and the 2nd accommodating part 27b are isolate | separated by the 1st insulating substrate 20a2, it is suitable for the piezoelectric device etc. which request | require high precision and high stability.
1-4, the thermal conductivity Tc of the insulating substrate constituting the container is desirably set to 120 [W / (m · K)] ≦ Tc ≦ 200 [W / (m · K)]. There is an effect that the temperature rise curves with respect to the time of the first and second electrode pads 28a, 28b, 29a, 29b become curves closer to each other.
1 to 4, if the thermal conductivity Tc of the insulating substrate constituting the container and the thermal conductivity of the wiring conductor are set to the same level, the first electrode pads 28 a and 28 b and the second electrode pads 29 a and 29 Are arranged so as to be equidistant from the mounting terminals, respectively, so that there is an effect that the temperature rise curve with respect to time becomes substantially the same regardless of the arrangement and length of the wiring conductor.

FIG. 5 is a diagram showing a configuration of an embodiment of the piezoelectric device 1 according to the present invention, in which FIG. 5 (a) is a plan view in which the lid member 38 is omitted, and FIG. 5 (b) is a diagram of Q in FIG. It is -Q sectional drawing. The piezoelectric device 1 includes the container 20 </ b> A according to the present invention illustrated in FIG. 1, a piezoelectric vibration element 10, and a temperature sensitive element (electronic element) 30. Cream solder is applied to the second electrode pads 29a and 29b provided on the first main surface (front portion) of the insulating substrate 20a1, and the temperature sensing element 30 is placed thereon, and the temperature sensing element 30 is passed through a reflow furnace. Secure the connection. After washing and drying this, the conductive adhesive 35 is applied to the first electrode pads 28a, 28b provided on the first main surface (front portion), and the piezoelectric vibration element 10 is placed thereon, After lightly pressing, the conductive adhesive 35 is dried and cured in a drying furnace. Further, annealing is performed at a high temperature in a vacuum furnace as necessary, and the space of the first main surface is hermetically sealed with a lid member 38 in a vacuum or in an inert gas atmosphere to complete the piezoelectric device 1. To do. The temperature sensitive element 30 may be fixed using solder balls, gold bumps, or the like instead of cream solder.
The embodiment shown in FIG. 5B is an example in which a container having a seal ring 42 provided on the peripheral edge of the first main surface S1 of the insulating substrate 20a1 is used, and a metallic concave lid member 38 is used. Is welded to the seal ring 42, the grounding mounting terminal 22c and the lid member 38 are conductively connected to each other by the via electrode 25, thereby providing a shielding effect.
Note that it is preferable to use metal bumps for fixing the temperature sensitive element 30 in consideration of degassing.
FIG. 5C shows a non-metallic lid member 38 formed by using a material such as ceramic or glass instead of the reverse lid-like metallic lid member 38 of the piezoelectric device 1 shown in FIG. It is an example of piezoelectric device 1 'comprised using. The inner wall surface of the lid member 38 is metallized in consideration of the shielding effect.

  FIG. 6 is a diagram showing the configuration of the piezoelectric device 2 according to the second embodiment. FIG. 6A is a plan view in which the lid member 38 is omitted, and FIG. It is Q sectional drawing and the figure (c) is a bottom view. The piezoelectric device 1 includes the container 20 </ b> B according to the present invention illustrated in FIG. 3, the piezoelectric vibration element 10, and a temperature sensitive element (electronic element) 30. Cream solder is applied to the second electrode pads 29a and 29b provided on the first main surface (front portion) of the insulating substrate 20a1, and the temperature sensing element 30 is placed thereon, and the temperature sensing element 30 is passed through a reflow furnace. Secure the connection. After washing and drying this, the conductive adhesive 35 is applied to the first electrode pads 28a, 28b provided on the first main surface (front portion), and the piezoelectric vibration element 10 is placed thereon, After lightly pressing, the conductive adhesive 35 is dried and cured in a drying furnace. A housing in which a metal lid member 38 is mounted on a fired seal ring 42 on the peripheral edge of the upper portion of the second insulating substrate 20b1, and the piezoelectric vibration element 10 and the temperature sensing element 30 are housed by means of resistance welding or the like. The part 27 is hermetically sealed to complete the piezoelectric device 2. The seal ring 42 and the grounding mounting terminal 22c are electrically connected by the via electrode 25, and the piezoelectric device 2 can have a shielding effect by welding the metal lid member 38 to the seal ring 42. it can.

As the piezoelectric vibration element 10 used in the embodiment shown in FIGS. 5 and 6, for example, an AT cut crystal vibration element is used. A piezoelectric material such as quartz belongs to the trigonal system and has crystal axes X, Y, and Z orthogonal to each other as shown in FIG. The X axis, the Y axis, and the Z axis are referred to as an electric axis, a mechanical axis, and an optical axis, respectively. The AT-cut quartz crystal substrate 12 is a flat plate cut out from the quartz crystal along a plane obtained by rotating the XZ plane around the X axis by an angle θ. In the case of the AT cut quartz substrate 12, θ is approximately 35 ° 15 ′. Note that the Y-axis and the Z-axis are also rotated by θ around the X-axis to be the Y′-axis and the Z′-axis, respectively. Accordingly, the AT-cut quartz substrate 12 has orthogonal crystal axes X, Y ′, and Z ′. The AT-cut quartz substrate 12 has a thickness direction of the Y ′ axis, and an XZ ′ plane (a plane including the X axis and the Z ′ axis) orthogonal to the Y ′ axis is a main surface, and a thickness shear vibration is a main vibration. Excited. For example, a BT cut or the like can be used although the cut angle is different from the AT cut.
If this cutting angle is used, there is an effect that the temperature characteristics required by the customer specifications can be appropriately realized.

An example of the piezoelectric substrate 12 shown in FIGS. 5 and 6 is centered on the X axis of an orthogonal coordinate system composed of an X axis (electrical axis), a Y axis (mechanical axis), and a Z axis (optical axis) as shown in FIG. In the plane parallel to the X axis and the Z ′ axis, the axis tilted in the −Y direction of the Y axis is the Z ′ axis, the axis tilted in the + Z direction of the Z axis is the Y ′ axis. It consists of an AT-cut quartz substrate having a thickness in a direction parallel to the Y ′ axis.
The external shape of the AT-cut quartz substrate is generally a rectangular shape whose longitudinal direction is the X-axis direction, and the resonance frequency depends on the thickness in the Y′-axis direction. High frequency, X side ratio (X / t, X is length in X axis direction, t is thickness), or Z side ratio (Z / t, Z is length in Z ′ axis direction, t is thickness) ) Is large, a flat-plate crystal substrate 12 is used as shown in FIGS. Further, when the frequency is low and the X-side ratio (X / t) or the Z-side ratio (Z / t) is small, a mesa-type quartz substrate (a quartz substrate having a thicker central portion than the peripheral portion) 12 is used. It is done. FIG. 8 shows an example of a mesa-type crystal resonator element. FIG. 8A is a plan view and FIG. 8B is a QQ cross-sectional view.
The mesa-type quartz substrate 12 includes an excitation unit 13 that is located in the center and serves as a main vibration region, a peripheral portion 15 that is thinner than the excitation unit 13 and is formed along the periphery of the excitation unit 13, and a sub vibration region. have. That is, the vibration region extends over the excitation unit 13 and a part of the peripheral unit 15. In the example shown in FIG. 8, there are two steps in the longitudinal direction (lateral direction in the drawing) of the piezoelectric substrate 12, and one step in the short direction (vertical direction in the drawing) as shown in FIG. 8 (b). This is an example of the piezoelectric vibration element 10 using a mesa-type piezoelectric substrate in which a step is formed.

In the piezoelectric vibration element 10, excitation electrodes 14 a and 14 b are formed on the front and back of the excitation unit 13 of the quartz substrate 12, and toward the terminal electrodes 18 a and 18 b provided at the end of the quartz substrate 12 from the excitation electrodes 14 a and 14 b. Extending lead electrodes 16a and 16b are formed.
When an alternating voltage is applied to the excitation electrodes 14a and 14b, the crystal resonator element 10 is excited in a specific vibration mode, for example, in the case of an AT cut crystal, the thickness shear mode.
Moreover, the thermosensitive element 30 used for the piezoelectric devices 1 and 1 ′ shown in FIGS. 5 and 6 uses a thermistor whose physical quantity, for example, electric resistance changes according to temperature change. A change in the electrical resistance of the thermistor 30 is detected by an external circuit, and the temperature of the thermistor 30 is measured. By detecting the temperature of the thermistor 30, the temperature of the piezoelectric vibration element 10 can be estimated.
Metal used for mounting terminals 22 (22a, 22b, 22c, 22d) such as containers 20A to 20C, via electrodes 23a, 23b, 23c, 23d, 25, and first and second wiring patterns 26a, 26b) Examples of the material include a tungsten material. A tungsten material can also be used as the seal ring (metallized portion) 42 formed on the periphery of the upper part of the second insulating substrates 20b1 and 20b2.

The heat conduction of the piezoelectric device according to the present invention will be described with reference to the piezoelectric device 2 shown in FIG. FIG. 9A is a cross-sectional view of the piezoelectric device 2 shown in FIG. 6, and FIG. 9B shows the thermal conductivity of each member used in the piezoelectric device 2. The main constituent member of a general container is alumina ceramics (Al ₂ O ₃ ), and its thermal conductivity Tc is 17 [W / (m · K)]. Main constituent members of the container according to the present invention are silicon carbide (SiC), aluminum nitride (AlN,) and the like, and the thermal conductivity thereof is 50 [W / (m · K)] to 200 [W / (m ·). K)] and extremely high thermal conductivity. Heat generated by an amplifier or the like mounted on the motherboard is conducted to the mounting terminal 22 from the land pattern on which the piezoelectric device 2 is mounted via the wiring pattern of the motherboard. Via electrodes 23a, 23b electrically connected to the first electrode pads 28a, 28b for the piezoelectric vibration element 10, via electrodes 23a, 23b electrically connected to the second electrode pads 29a, 29b for the temperature sensitive element 30, and grounding It is assumed that the via electrode 25 that electrically connects the mounting terminal 22c and the lid member 38 is formed of tungsten (W) having an extremely high melting point. Tungsten (W) has a thermal conductivity of 167 [W / (m · K)]. Among metals, it has the second highest heat after silver (420), copper (398), gold (320), aluminum (236), etc. It has conductivity.

The main constituent material of the container of the present invention is silicon carbide (SiC), aluminum nitride (AlN, etc.), and the thermal conductivity Tc thereof is equal to or higher than that of tungsten (W). . Therefore, unlike the conventional container, heat is not conducted mainly via the mounting terminal 22 and the via electrode and the castellation electrode, but from the mounting terminal 22 from silicon carbide (SiC), aluminum nitride (AlN), or the like. Conducting to the first and second electrode pads 28a, 28b, 29a, 29b through the inside of the first and second insulating substrates 20a1, 20b1 in three dimensions, the piezoelectric vibrating element 10, the temperature sensitive The temperature of the element 30 is raised. Further, the heat conducted to the second insulating substrate 20b1 is transmitted to the lid member 38, and the piezoelectric vibration element 10 and the temperature sensitive are radiated from the lid member 38 and the first main surface (front portion) of the first insulating substrate 20a1. The temperature of the element 30 is raised.
Since the first electrode pads 28a and 28b and the second electrode pads 29a and 29b are disposed at substantially symmetrical positions with respect to the mounting terminal 22, the heat from the mounting terminal 22 causes the piezoelectric vibration element 10 to The temperature rise curve and the temperature rise curve of the temperature sensing element 30 are substantially similar curves. That is, when a temperature compensated oscillator is configured by using an external oscillation circuit and a compensation circuit together, the temperature sensing element 30 can accurately detect the temperature of the piezoelectric vibrator 10, and frequency drift characteristics and frequency An oscillator having excellent temperature characteristics can be configured.

FIG. 10A shows the piezoelectric vibration element 10 (broken line) and the temperature sensitive element 30 (after power-on of the piezoelectric device 2 configured by mounting the piezoelectric vibration element 10 and the temperature sensitive element 30 on the container 20B according to the present invention. A solid line) and a curve showing a temperature change. Since the heat conduction path is three-dimensional, the temperature rises of the piezoelectric vibration element 10 and the temperature sensitive element 30 are maintained at substantially the same temperature as shown in FIG. The temperature reached after elapses).
On the other hand, FIG. 10B shows the piezoelectric vibration element 10 in the piezoelectric device configured using a conventional container mainly composed of alumina ceramics (Al ₂ O ₃ ) and the temperature-sensitive element 30 after the power is turned on. It is an example of the curve which showed the temperature change. There is a temperature difference between the temperature of the piezoelectric vibration element 10 and the temperature of the temperature-sensitive element 30, and the temperature difference is not reduced unless time elapses.
FIG. 10C shows the temperature difference between the thermal conductivity Tc of the material constituting the container 20 and the temperature of the piezoelectric vibration element 10 and the temperature of the thermosensitive element 30 when measured at a predetermined time after the power is turned on. It is a curve which shows the relationship with (DELTA) T. As the thermal conductivity of the material increases, the temperature difference ΔT at a predetermined time decreases.
As described above, when the piezoelectric device of the present invention is mounted on a mother board and a reference oscillator is configured using an oscillation circuit and a temperature compensation circuit, an oscillator having excellent frequency drift characteristics can be configured.

FIG. 11 is a diagram illustrating the configuration of the piezoelectric device 3 according to the third embodiment. FIG. 11A is a plan view in which the lid member 38 is omitted, and FIG. 11B is a diagram of FIG. It is QQ sectional drawing and the figure (c) is a bottom view. The piezoelectric device 3 is different from the piezoelectric device 2 shown in FIG. 6 in the configuration of the container 20 </ b> D constituting the piezoelectric device 3 and the positional relationship between the piezoelectric vibration element 10 and the temperature sensitive element 30. In other words, the present embodiment is characterized in that the pair of first electrode pads 28a, 28b for the piezoelectric vibration element 10 and the pair of second electrode pads 29a, 29b for the temperature sensitive component 30 are arranged close to each other. Is. In the case of the piezoelectric device 3, as in the piezoelectric device 2, the temperature difference between the temperature of the piezoelectric vibration element 10 and the temperature of the thermosensitive element 30 is the temperature equilibrium point (time sufficiently The temperature reached after elapses).
Similar to the piezoelectric device 2 shown in FIG. 6, a shielding effect can be provided by electrically connecting the mounting terminal 22 c for grounding and the lid member to the via electrode 25. Note that the first and second insulating substrates 20a2 and 20b2 are made of a material having high thermal conductivity such as silicon carbide (SiC) or aluminum nitride (AlN).

  FIG. 12 is a diagram illustrating the configuration of the piezoelectric device 4 according to the fourth embodiment. FIG. 12A is a plan view in which the lid member is omitted, and FIG. It is sectional drawing and the figure (c) is a bottom view. The difference from the piezoelectric device 2 shown in FIG. 6 is the structure of the container 20E of the piezoelectric device 4. A container 20E of the piezoelectric device 4 is a container obtained by laminating and firing a first insulating substrate 20a3, a second insulating substrate 20b3, and a third insulating substrate 20c3. On the first main surface (front surface) of the first insulating substrate 20a3, a pair of second electrode pads 29a and 29b for mounting the temperature sensing element 30 and a second wiring pattern 26b are formed, and the second Mounting terminals 22 (22a to 22d) are formed at corners of the main surface (back surface). Further, via electrodes 23a and 23b and via electrodes 24a and 24b are formed inside the thickness of the first insulating substrate 20a3. The mounting terminals 22c and 22d are electrically connected to the second electrode pads 29a and 29b for mounting the temperature sensing element 30 via the via electrodes 24a and 24b and the second wiring patterns 26b and 26b.

  Further, the second insulating substrate 20b3 of the container 20E of the piezoelectric device 4 is an annular flat plate having a space portion at the center, and is a bottom portion with respect to the first main surface (front portion) of the first insulating substrate 20a3. The stack is fixed. A pair of first electrode pads 28a, 28b for mounting the piezoelectric vibration element 10 are juxtaposed along the short side direction near the end of the front portion of the second insulating substrate 20b3. A pair of first electrode pads 28a, 28b and via electrodes 23c, 23d, one end of which is electrically connected to each other, are formed in the thickness of the second insulating substrate 20b3, and the other ends are respectively formed in the first insulating substrate 20a3. The via electrodes 23a and 23b are electrically connected. The temperature sensitive element 30 is accommodated in the second accommodating portion 27b formed by the first main surface (front portion) of the first insulating substrate 20a3 and the space portion of the annular second insulating substrate 20b3. The third insulating substrate 20c3 is an annular body, and the bottom portion is laminated and fixed to the front portion of the second insulating substrate 20b3. The piezoelectric vibration element 10 is accommodated in the first accommodating portion 27a configured by the front portion of the second insulating substrate 20b3 and the hollow portion of the third insulating substrate 20c. A seam ring 42 made of tungsten (W) or the like is fired around the upper peripheral edge of the third insulating substrate 20c3, the lid member 38 is resistance-welded, and the first accommodating portion 27a is hermetically sealed. A via electrode 25 that electrically connects the mounting terminal 22c and the seam ring 42 is formed through the first, second, and third insulating substrates 20a3, 20b3, and 20c3. The first, second, and third insulating substrates 20a3, 20b3, and 20c3 are configured using a material having high thermal conductivity such as silicon carbide (SiC) and aluminum nitride (AlN).

  When manufacturing the piezoelectric device 4, cream solder or the like is applied to the electrode pads 29a and 29b in the second accommodation portion 27th second of the container 20E described above, and the temperature sensitive element 30 is placed thereon, The temperature sensitive element 30 is fixed by heating. Subsequently, after the first and second accommodating portions 27a and 27b are cleaned and dried, the conductive adhesive 35 is applied to the first electrode pads 28a and 28b of the first accommodating portion 27a, and the piezoelectric material is applied thereon. The vibrating element 10 is placed and pressed lightly, and held in a drying furnace at a predetermined temperature for a predetermined time, and the conductive adhesive 35 is dried and cured. Further, the piezoelectric vibration element 10 is annealed in a vacuum furnace as necessary. Thereafter, the first housing portion 27a is hermetically sealed with the lid member 38 in a vacuum or in an inert gas atmosphere to complete the piezoelectric device 4. The temperature sensitive element 30 may be fixed using solder balls, gold bumps, or the like instead of cream solder.

  FIG. 13 is a diagram illustrating the configuration of the piezoelectric device 5 according to the fifth embodiment. FIG. 13A is a plan view in which the lid member is omitted, and FIG. It is sectional drawing and the figure (c) is a bottom view. The piezoelectric device 5 is a piezoelectric device configured using the container 20C according to the present invention shown in FIG. As shown in FIG. 13B, the piezoelectric device 5 is connected to an oscillation circuit component and a compensation circuit component mounted on the main circuit board and outputs a desired frequency, and the piezoelectric vibration element 10. The temperature sensing element 30 for detecting the temperature of the first and the first accommodation portion 27a for accommodating the piezoelectric vibration element 10 are provided on the first main surface S1 side of the first insulating substrate 20a2, and the temperature sensing element 30 is accommodated. A container 20C having the second storage portion 27b on the second main surface S2 side and a lid member 38 for sealing the first storage portion 27a are provided.

  When the piezoelectric device 5 is manufactured, the conductive adhesive 35 is applied to the first electrode pads 28a and 28b of the container 20C shown in FIG. 4, and the piezoelectric vibration element 10 is placed on the first electrode pad 28a and 28b. The conductive adhesive 35 is dried and cured by holding for a predetermined time in a drying furnace at a temperature of 5 mm. If necessary, the piezoelectric vibrating element 10 is annealed in a vacuum furnace at a high temperature for a predetermined time. Thereafter, the first accommodating portion 27a is hermetically sealed with the lid member 38 in a vacuum or in an inert gas atmosphere. Subsequently, the container 20C is inverted, cream solder or the like is applied to the second electrode pads 29a and 29b, the temperature sensitive element 30 is placed thereon, and the temperature sensitive element 30 is fixed by heating, thereby the piezoelectric device. Complete 5. The temperature sensitive element 30 may be fixed using solder balls, gold bumps, or the like instead of cream solder.

  FIG. 14A is a cross-sectional view showing the configuration of the piezoelectric device 6 according to the sixth embodiment, FIG. 14B is a plan view of the container 20F, and FIG. It is QQ sectional drawing of). The configuration of the piezoelectric device 4 is different from the configuration of the piezoelectric device 2 shown in FIG. 6 in that, as shown in FIG. 14, a thick annular seal is formed on the peripheral portion of the first main surface (front surface) of the first insulating substrate 20a4. This is the point where the ring 42 is fired. The first main surface (front surface) of the first insulating substrate 20a4 and the thick annular seal ring 42 constitute the accommodating portion 27. The cover 27 can be hermetically sealed by seam welding a cover member 38 such as Kovar to the top of the seal ring 42. In the case of the piezoelectric device 6, a flat metal plate can be used as the lid member 38. The insulating substrate 20a4 is configured using a material having high thermal conductivity such as silicon carbide (SiC) or aluminum nitride (AlN).

  Since the piezoelectric devices 1 to 6 are configured using the container or the like shown in FIGS. 1 to 4 according to the present invention, the elapsed time between the piezoelectric vibration element 10 after power-on and the electronic element 30 for detecting temperature. As a result, the temperature oscillation curve with respect to the above can be made substantially the same, so that an external oscillation circuit component and a compensation circuit component can be used together to form a temperature compensated reference oscillator having a small frequency drift characteristic.

FIG. 15 is a schematic block diagram showing a configuration of a digital mobile phone 100 using the piezoelectric device 7 of the seventh embodiment. The piezoelectric device 7 uses the container 20B described with reference to FIG. 3. The tuning fork type crystal resonator element 10b is accommodated in the accommodating portion 27, and the accommodating portion 27 is vacuumed and sealed with the lid member 38. The piezoelectric device 7 is configured by being fixed to the side surface with an adhesive.
In the case of transmitting sound with the digital cellular phone 100 shown in FIG. 15, when the user inputs his / her own sound into the microphone, the signal passes through the pulse width modulation / coding circuit and the modulator / demodulator circuit to the transmitter and antenna. It is transmitted from the antenna through the switch. On the other hand, a signal transmitted from another person is received by an antenna, passes through an antenna switch, a reception filter + amplifier circuit, etc., enters a receiver circuit, and is input from this receiver circuit to a modulator / demodulator circuit. The signal demodulated by the demodulator circuit is output as a sound from a speaker via a pulse width modulation / coding circuit. A controller is provided to control the antenna switch, the modulator / demodulator circuit, and the like.

In addition to the functions described above, this controller controls the LCD, which is the display unit, the keys, which are input units for numbers, etc., and the RAM, ROM, etc. High stability is required. In order to meet this demand, the piezoelectric device 7 shown in FIG. 16 is a piezoelectric device configured by accommodating the tuning-fork type crystal vibrating element 10b and the temperature sensitive element 30 in the accommodating portion 27 of the container 20B.
That is, the difference between the piezoelectric device 7 of the seventh embodiment and the piezoelectric device 2 shown in FIG. 6 is that, in the piezoelectric device 2, the piezoelectric vibration element 10 uses a thickness shear vibration element, but the piezoelectric device 7. However, the difference is that a tuning fork type crystal vibrating element 10b that performs bending vibration is used. The piezoelectric device 2 is suitable when a high frequency reference frequency is required, and the piezoelectric device 7 is suitable when a low frequency reference frequency is required.
Since the tuning-fork type crystal resonator element 10b is used for the piezoelectric resonator element 10, there is an advantage that a desired low-frequency reference oscillator can be obtained without requiring a circuit for dividing a high frequency. In addition, when an electronic apparatus is manufactured using the above-described piezoelectric device, a reference frequency source having high stability and excellent frequency drift characteristics can be easily configured.

  A tuning fork type piezoelectric vibration element will be briefly described. FIG. 17A is a plan view of the tuning fork type piezoelectric vibration element 10b, and FIG. 17B is a cross-sectional view taken along the line P-P in FIG. The piezoelectric substrate 52 is formed using a photolithography technique and an etching technique. As shown in FIG. 17A, the tuning fork type piezoelectric vibration element 10b includes a plurality of narrow belt-shaped vibrating arms 55a and 55b that are parallel (parallel) to each other and extend linearly, and one of the vibrating arms 55a and 55b. A base portion 54 that connects the end portions (base end portions), and groove portions 57a, 57b, 58a, and 58b formed on the front and back surfaces of the vibrating arms 55a and 55b, respectively, along the vibration center line. Yes.

FIG. 17B is a cross-sectional view taken along the line P-P in FIG. 17A, and is a cross-sectional view showing the arrangement of the excitation electrodes 60, 62, 64, 66 formed on the respective vibrating arms 55 a, 55 b. Excitation electrodes 60 and 64 are formed on the surfaces and side surfaces of the respective groove portions 57a (57b) and 58a (8b), and excitation electrodes 62 and 66 are formed on both side surfaces of the respective vibrating arms 55a and 55b. The excitation electrodes 60 and 66 and the excitation electrodes 62 and 64 are configured such that voltages having different signs are applied to each other via an electrode pad (not shown) of the base 54. That is, when a positive voltage is applied to the excitation electrodes 60 and 66, a negative voltage is applied to the excitation electrodes 62 and 64, and an electric field as indicated by an arrow in FIG. A tuning fork vibration (bending vibration) that is symmetrical with respect to the center line passing through is excited.
In addition, by forming the grooves 57a (57b) and 58a (58b), the electric field strength is increased, and tuning fork vibration can be excited more efficiently. That is, the CI (crystal impedance) of the piezoelectric vibration element can be reduced.

FIG. 18 is a diagram illustrating a configuration of the piezoelectric device 8 according to the eighth embodiment. FIG. 18A is a plan view, and FIG. 18B is a QQ cross-sectional view of FIG. The piezoelectric device 8 is different from the piezoelectric device 2 shown in FIG. 6 in that it is formed by the first main surface (front surface) of the first insulating substrate 20a5 and the space portion of the second insulating substrate 20b5 which is an annular flat plate. This is because the piezoelectric vibration element 10a in the thickness-shear vibration mode and the tuning-fork type piezoelectric vibration element 10b in the bending vibration mode are accommodated in the accommodating portion 27. Since the two piezoelectric vibration elements 10a and 10b are juxtaposed, four first electrode pads 28a to 28d are required, and four corresponding via electrodes are also required. As the number of via electrodes increases, the number of mounting terminals also increases.
The piezoelectric device 8 is useful for an electronic apparatus that requires two reference frequencies, a low frequency and a high frequency, and two high-accuracy frequencies can be obtained with one temperature-sensitive component 30.
By using the piezoelectric device 8 in combination with an external circuit having an oscillation circuit component and a compensation circuit component, two high-frequency and low-frequency piezoelectric oscillators are configured, temperature compensated, highly stable, and excellent in frequency drift characteristics. There is an effect that two reference frequencies can be obtained.

DESCRIPTION OF SYMBOLS 1, 1'2, 3, 4, 5, 6, 7, 8 ... Piezoelectric device 10, 10a, 10b ... Piezoelectric vibration element, 12 ... Piezoelectric substrate, 13 ... Excitation part, 14a, 14b ... Excitation electrode, 15 ... Peripheral part, 16a, 16b ... lead electrode, 18a, 18b ... terminal electrode, 20, 20A, 20B, 20C, 20D, 20E, 20F, 20G ... container, 20a, 20a1, 20a2, 20a3, 20a4, 20a5 ... first Insulating substrate, 20b, 20b1, 20b2, 20b3, 20b5 ... Second insulating substrate, 20c2, 20c3 ... Third insulating substrate, 22, 22a, 22b, 22c, 22d ... Mounting terminals, 23a, 23b, 23c, 23d, 25 ... via electrode, 26a ... first wiring pattern, 26b ... second wiring pattern, 27 ... accommodating portion, 27a ... first accommodating portion, 27b ... second accommodating portion, 28 28b ... first electrode pad, 29a, 29b ... second electrode pad, 30 ... temperature sensitive element, 35 ... conductive adhesive, 38 ... lid member, 42 ... sealing ring, C1, C2, C3, C4 ... Castellation, Ce1, Ce2, Ce3, Ce4 ... castellation electrode, S1 ... first main surface, S2 ... second main surface

Claims (12)

A first electrode pad on which a vibration element is mounted on the first main surface side;
A second electrode pad on which the electronic element is mounted;
Have
An insulating substrate having a plurality of mounting terminals on the second main surface side opposite to the first main surface;
A lid member that hermetically seals the space on the first main surface side including the vibration element and the electronic element;
A container comprising
The mounting terminal and the first and second electrode pads are:
Each is electrically connected by a wiring conductor,
The thermal conductivity Tc of the material mainly constituting the insulating substrate is
50 [W / (m · K)] ≦ Tc ≦ 200 [W / (m · K)]
A container characterized by satisfying   The container according to claim 1, wherein a seal ring is provided on a peripheral edge of the first main surface of the insulating substrate. A first electrode pad on which a vibration element is mounted on the first main surface side;
A second electrode pad on which the electronic element is mounted;
Have
A first insulating substrate having a plurality of mounting terminals on the second main surface side opposite to the first main surface;
An annular second insulating substrate whose bottom is laminated and fixed to the first main surface of the first insulating substrate;
A lid member hermetically sealing a space including the vibration element and the electronic element located in the hollow portion of the second insulating substrate;
A container comprising
The mounting terminal and the first and second electrode pads are:
Each is electrically connected by a wiring conductor,
The thermal conductivity Tc of the material mainly constituting the insulating substrate is
50 [W / (m · K)] ≦ Tc ≦ 200 [W / (m · K)]
A container characterized by satisfying A first electrode pad on which a vibration element is mounted on the first main surface side;
A second electrode pad on which an electronic element is mounted on the second main surface side opposite to the first main surface;
A first insulating substrate having:
An annular second insulating substrate that forms a first housing portion by stacking and fixing a bottom portion to the first main surface of the first insulating substrate;
An annular third insulating substrate having a plurality of mounting terminals on the bottom, forming a second housing portion by stacking and fixing a front portion to the second main surface side,
A lid member that hermetically seals the space including the vibration element located in the hollow portion of the second insulating substrate;
The mounting terminal and the first and second electrode pads are electrically connected by wiring conductors, respectively.
The thermal conductivity Tc of the material mainly constituting the first, second and third insulating substrates is
50 [W / (m · K)] ≦ Tc ≦ 200 [W / (m · K)]
A container characterized by satisfaction. The thermal conductivity Tc is
120 [W / (m · K)] ≦ Tc ≦ 200 [W / (m · K)]
The container according to any one of claims 1 to 4, wherein:   The container according to any one of claims 1 to 4, wherein the thermal conductivity Tc is equal to the thermal conductivity of the wiring conductor.   A vibrating device comprising a vibrating element and an electronic element mounted on the container according to any one of claims 1 to 6.   The said lid member is electrically connected with the said mounting terminal by the conductor which penetrates the inside of the said container, or the castellation electrode provided in the outer surface of the said container. Vibration device.   The vibrating device according to claim 7, wherein the vibrating element is a tuning fork type quartz vibrating element. The substrate of the vibration element is centered on the X axis of an orthogonal coordinate system including an X axis as an electric axis that is a crystal axis of quartz, a Y axis as a mechanical axis, and a Z axis as an optical axis.
An axis obtained by inclining the Z axis by a predetermined angle in the −Y direction of the Y axis is defined as a Z ′ axis.
An axis obtained by inclining the Y axis by the predetermined angle in the + Z direction of the Z axis is a Y ′ axis,
It is composed of a plane parallel to the X axis and the Z ′ axis,
A quartz substrate having a thickness in a direction parallel to the Y ′ axis,
The side parallel to the X axis is the long side,
The vibration device according to claim 7 or 8, wherein a quartz substrate having a side parallel to the Z 'axis as a short side is used.   9. The vibration device according to claim 7, wherein an AT-cut crystal vibration element and a tuning fork type crystal vibration element are juxtaposed as the vibration element in the housing portion.   An electronic apparatus comprising the vibration device according to any one of claims 7 to 11.

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