JP2013055572A - Piezoelectric device and electronic apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a small size piezoelectric device which is connected with an external circuit and is excellent in both frequency temperature characteristics and frequency drift characteristics (short term stability).SOLUTION: A piezoelectric device comprises: a piezoelectric vibration element 10; a temperature-sensitive component 30; and a container 20. The container 20 comprises: a first insulating substrate 20a which has first electrode pads 28a and 28b on a front surface, second electrode pads 29a and 29b on a rear surface and mounting terminals 22; an annular second insulating substrate 20b; and mounting conductive members 36 conductively fixed to the mounting terminals 22. The mounting terminals 22 and the first electrode pads 28a and 28b are electrically and thermally connected to one another through first heat conductive members and the mounting terminals 22 and the second electrode pads 29a and 29b are electrically and thermally connected to one another through second heat conductive members, respectively.

Description

  The present invention relates to a piezoelectric device including a temperature-sensitive component and a piezoelectric vibration element. The present piezoelectric device and an IC component mounted on a main circuit board (motherboard) together constitute an accurate temperature compensated piezoelectric oscillator, and also relates to a piezoelectric module and an electronic apparatus using the piezoelectric device.

  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 that uses a circuit having a fourth or higher-order component related to temperature as a temperature compensation circuit to reduce frequency drift after power-on. 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 the conductive film (castellation electrode) is used as a means for electrical conduction between a mounting terminal and an element mounting pad. Is disclosed. Note that the castellation extending vertically in the four corners of the insulating container is used when cutting a plurality of containers into a separate container 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 disposed 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 part is divided in half and the first IC part with the temperature sensor is accommodated in the same cavity as the piezoelectric vibration element is low in cost and not feasible, and goes against the downsizing of the entire oscillator. There is a problem of doing.
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.

However, in the structure disclosed in Patent Document 10, although the thermistor is connected to the container of the piezoelectric vibrator, since the container is an insulating ceramic, the actual piezoelectric vibrating element in the container is actually in view of thermal conductivity. There is a problem that a temperature difference is generated between the temperature and the temperature detected by the thermistor. Further, since the thermistor is fixed so as to protrude to the outside of the container, there is a problem that it may be broken or dropped due to handling or contact with other parts.
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.

Patent Document 12 discloses a crystal oscillator in which a crystal resonator is mounted on a flexible wiring board via a metal ball. In the crystal oscillator, electronic components are mounted directly on the land pattern on one side of the flexible wiring board, and metal balls are mounted on the land pattern provided on the outer peripheral edge of the flexible wiring board. A crystal resonator having the same planar shape is mounted so as to cover the upper surface of the electronic component and to make the land-mount terminals and the land pattern provided on the bottom surface of the ceramic package of the crystal resonator conductive through metal balls.
Patent Document 13 discloses a method for manufacturing a piezoelectric oscillator in which a solder ball is bonded to a mounting terminal of a container of a piezoelectric vibrator, and a semiconductor component is accommodated in a space formed by the container bottom and the solder ball. Solder balls are used when a piezoelectric oscillator is mounted on a motherboard.

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 Japanese Patent No. 3956614 Japanese Patent Laid-Open No. 2007-235483

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 insulating ceramic, from the viewpoint of thermal conductivity, the temperature 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. There was a problem that a temperature difference occurred. Further, in the structure disclosed in Patent Document 10, there is a problem that a temperature difference occurs between the actual temperature of the piezoelectric vibration element and a temperature detected by the thermistor, and there is a problem that damage or dropout may occur during handling. . Further, in the structure disclosed in Patent Document 11, if the piezoelectric vibrating element has poor characteristics, the thermistor must be discarded, resulting in a high cost.
Patent Documents 12 and 13 do not mention the temperature difference between the temperature of the piezoelectric vibrator and the temperature sensitive element that senses the temperature.
In other words, the disclosed structure is not sufficient to satisfy the GPS standard mounted on the mobile phone, and the further improvement is required from the results verified by the present inventors. It was.
The present invention has been made in view of the above, makes it possible to detect the temperature of a piezoelectric vibration element with high accuracy, and is highly stable by combining with a compensation circuit mounted on a main circuit board (motherboard). An object of the present invention is to provide a small surface-mount type piezoelectric device that enables an oscillator with high-accuracy frequency temperature characteristics.

  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 piezoelectric device according to the present invention includes a piezoelectric vibration element, an electronic element having a pair of electrodes at both ends, and the piezoelectric vibration element mounted on a first main surface. An insulating substrate on which the electronic element is mounted on the second main surface on the opposite side, and the insulating substrate has a first electrode pad for mounting the piezoelectric vibration element on the first main surface side, 2 has a second electrode pad for mounting the electronic element and a plurality of mounting terminals on the main surface side, and the second main surface side is conductively fixed to the mounting terminal. A conductive member for mounting that is taller than the electronic element mounted on the electrode pad, wherein at least one of the mounting terminal and the first electrode pad are electrically and thermally heated by the first heat conductive member. The at least one other mounting terminal and the second electrode pad are connected to each other. A piezoelectric device which is characterized in that it is electrically and thermally connected by a thermal conduction member.

  According to this configuration, the piezoelectric device is effective in reducing the height and cost, and the flow of heat transmitted from the mounting terminal (heat conduction) by appropriately setting the first and second heat conducting members. This speed is high, and the temperature difference between the temperature of the piezoelectric vibration element and the temperature detected by the temperature-sensitive component can be reduced in a short time.

  [Application Example 2] The piezoelectric device according to Application Example 1, wherein the piezoelectric device is provided with a seal ring at a peripheral edge on the first main surface side of the insulating substrate.

  According to this configuration, there is an advantage that the piezoelectric device has a low profile, a cost reduction, a reduction in temperature difference between the piezoelectric vibration element and the electronic element, and a shielding effect by grounding the lid member. .

  Application Example 3 In addition, the piezoelectric device is a piezoelectric device including a piezoelectric vibration element, a temperature-sensitive component that detects temperature, and a container having a housing portion that houses the piezoelectric vibration element, A first electrode pad for mounting the piezoelectric vibration element on the first main surface side, a second electrode pad for mounting the temperature sensitive component on the second main surface side, and a plurality of mounting terminals. A first insulating substrate having an annular second insulating substrate having a bottom portion laminated and fixed to the first main surface side of the first insulating substrate to form the housing portion; and conductive to the mounting terminal A mounting conductive member that is fixed and taller than the temperature-sensitive component mounted on the second electrode pad, wherein at least one of the mounting terminals and the first electrode pad includes a first It is electrically and thermally connected by a heat conducting member, and at least one other said actual From said terminal second electrode pad, a piezoelectric device which is characterized in that it is electrically and thermally connected by a second heat conducting member.

  According to the above configuration, the diameter and length of the first heat conducting member that electrically connects the mounting terminal and the first electrode pad, and the second heat conduction that electrically connects the mounting terminal and the second electrode pad. By appropriately setting the length width of the member, the temperature difference between the temperature of the piezoelectric vibration element and the temperature detected by the temperature-sensitive component can be reduced. As a result, the temperature difference between the temperature of the piezoelectric vibration element and the temperature detected by the temperature-sensitive component can be reduced in a short time, and it is connected to an external circuit to provide excellent frequency drift characteristics (short-term stability). Since the temperature compensated piezoelectric oscillator can be realized, the performance of GPS and the like can be improved.

  Application Example 4 In the piezoelectric device, the first main surface side is hermetically sealed by a concave lid member so as to cover the piezoelectric vibration element, and the lid member passes through the interior of the container. The piezoelectric device according to Application Example 2, wherein the piezoelectric device is electrically and thermally connected to a mounting terminal connected to the temperature-sensitive component by a conductive member.

  According to said structure, there exists an advantage that a shielding effect arises by carrying out conductive connection with the cover member and the mounting terminal by the 3rd heat conductive member, and being earth | grounded.

  Application Example 5 In addition, the piezoelectric device includes a lid member that hermetically seals the housing portion, and the lid member is connected to the temperature-sensitive component by a third heat conductive member that penetrates the inside of the container. The piezoelectric device according to Application Example 3, wherein the piezoelectric device is electrically and thermally connected to a terminal.

  According to the above configuration, the effect that the temperature difference between the piezoelectric vibration element and the temperature-sensitive component is reduced, and the lid member and the mounting terminal are conductively connected by the third heat conducting member and grounded, thereby shielding There is an advantage that an effect is produced.

  Application Example 6 In the piezoelectric device, application examples 2 to 5 are characterized in that at least a part of the first and third heat conducting members are disposed through the first insulating substrate. It is a piezoelectric device as described in any one of these.

  According to the above configuration, since the heat transmitted from the mounting terminal passes through the first and third heat conducting members, the speed of the heat flow (heat conduction) is high, and the temperature of the piezoelectric vibration element can be measured in a very short time. There is an effect that the temperature difference from the temperature detected by the temperature sensitive component can be reduced.

  Application Example 7 In the piezoelectric device, the insulating substrate includes a castellation on a side surface, a metal layer is provided on the surface of the castellation, and at least one of the first and third heat conducting members. The piezoelectric device according to any one of application examples 2 to 5, wherein at least a part of the piezoelectric device is arranged and connected to a castellation provided on an outer surface of the metal layer container. .

  According to the above configuration, by providing at least one of the first and third heat conducting members in the castellation, the speed of the heat flow (heat conduction) transmitted from the mounting terminal is fast, and in an extremely short time. There is an effect that the temperature difference between the temperature of the piezoelectric vibration element and the temperature detected by the temperature-sensitive component can be reduced.

  Application Example 8 In the piezoelectric device, at least a part of one of the first and third heat conducting members is disposed through the inside of the first insulating substrate, and at least a part of the other is the above-described one. 6. The piezoelectric device according to any one of application examples 2 to 5, wherein the piezoelectric device is disposed in a castellation provided on an outer surface of the container.

  According to said structure, the flow (heat conduction) of the heat transmitted from a mounting terminal is the caster provided in the 1st and 3rd heat conductive member provided in the thick part of the 1st insulated substrate, and the container side surface. Therefore, there is an effect that the temperature difference between the temperature of the piezoelectric vibration element and the temperature detected by the temperature-sensitive component can be reduced in a very short time.

  Application Example 9 In place of the second insulating substrate, an annular metal substrate is employed, and a lid member that hermetically seals the opening of the annular metal substrate is provided, and the lid member includes the container It is electrically and thermally connected to a mounting terminal connected to the temperature-sensitive component by the third heat conducting member penetrating the inside of the metal plate or the metal layer provided on the surface of the castellation. The piezoelectric device according to any one of Application Examples 1 to 8.

  According to said structure, since the cyclic | annular metal board | substrate is used, it is effective in the shortening and cost reduction of a piezoelectric device.

  Application Example 10 In the piezoelectric device, the piezoelectric substrate of the piezoelectric vibration element includes an X axis as an electric axis that is a crystal axis of crystal, 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 with the X axis of the orthogonal coordinate system as a center is defined as a Z ′ axis, and the Y axis is in the + Z direction of the Z axis. The quartz substrate is formed by a plane parallel to the X-axis and the Z′-axis, the axis tilted by this angle being the Y′-axis, and the direction parallel to the Y′-axis is the thickness, and is parallel to the X-axis. 10. An AT-cut quartz crystal resonator element using a quartz substrate having a long side as a long side and a side parallel to the Z ′ axis as a short side, according to any one of application examples 1 to 9. This is a piezoelectric device.

  According to the above configuration, for example, by using an AT-cut quartz substrate for the piezoelectric substrate, the frequency temperature characteristic of the piezoelectric device becomes an excellent third-order characteristic, and the temperature compensation technology accumulated for a long time is utilized. A frequency-temperature characteristic is obtained. In addition, the AT-cut quartz substrate etching method has a long experience, has a good yield, and can mass-produce a small piezoelectric substrate at a high frequency, which has the advantage of reducing the cost of the piezoelectric device.

  [Application Example 11] The piezoelectric device according to any one of Application Examples 1 to 9, wherein the piezoelectric vibration element is a tuning-fork type crystal vibration element.

  According to said structure, there exists an advantage that the required reference | standard low frequency excellent in the temperature characteristic can be obtained, without dividing a high frequency by using a tuning fork type crystal vibration element for a piezoelectric vibration element.

  Application Example 12 In the piezoelectric device, the piezoelectric vibration element is characterized in that an AT-cut crystal vibration element and a tuning fork type crystal vibration element are juxtaposed in the housing portion.

  According to the above configuration, when used in combination with an external circuit, two frequencies of high frequency and low frequency are temperature-compensated, and two reference frequencies having high stability and excellent short-term stability are obtained.

  Application Example 13 An electronic apparatus according to the present invention is an electronic apparatus including the piezoelectric device according to any one of Application Examples 1 to 12 incorporated therein.

  When an electronic apparatus is manufactured using the above-described piezoelectric device, a reference frequency source having high stability and excellent short-term stability can be easily configured.

It is the schematic which shows the structure of the piezoelectric device 1 which concerns on this invention, (a) is a top view except the cover member, (b) is QQ sectional drawing, (c) is a bottom view. (A) of a 1st insulated substrate is a top view (front view), (b) is a back view. (A) of the 1st insulated substrate which concerns on other embodiment is a top view (front view), (b) is a back view. (A) of the 1st insulated substrate which concerns on other embodiment is a top view (front view), (b) is a back view. (A) of the 1st insulated substrate which concerns on other embodiment is a top view (front view), (b) is a back 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 sectional drawing explaining the conduction of heat of the piezoelectric device 1, (b) is a figure explaining the thermal conductivity of a member. FIG. 3 is a cross-sectional view illustrating heat conduction of the piezoelectric device 2. (A) is a top view which abbreviate | omitted the cover member which shows the structure of the piezoelectric device 3, (b) is QQ sectional drawing of (a), (c) is a bottom view. FIG. 3 is a cross-sectional view showing a configuration of a piezoelectric device 4. The structure of the piezoelectric device 5 is shown, (a) is a sectional view, (b) is a surface view of a first insulating substrate, and (c) is a QQ sectional view 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 6. 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 7, (a) is a top view except the cover member, (b) is QQ sectional drawing of (a). (a) is sectional drawing which shows the structure of the piezoelectric device 8, (b) is sectional drawing which shows the structure of piezoelectric device 8 '. FIG. 3 is a cross-sectional view showing a configuration of a piezoelectric device 9.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a schematic diagram showing a configuration of a piezoelectric device 1 according to an embodiment of the present invention. FIG. 1A is a plan view in which the lid member is omitted, FIG. 1B is a cross-sectional view taken along the line QQ of FIG. 1A, and FIG. 1C is a bottom view. As shown in FIG. 1B, the piezoelectric device 1 is connected to an external oscillation circuit and compensation circuit (oscillation circuit component and compensation circuit component mounted on the main circuit board) and outputs a desired frequency. The piezoelectric vibration element 10, a temperature sensitive component 30 that detects the temperature of the piezoelectric vibration element 10, and a housing portion 27 that houses the piezoelectric vibration element 10 in the front portion (upper portion in FIG. 1B) are provided on the bottom surface side. A container (package main body) 20 having a pair of electrode pads to which the temperature-sensitive component 30 is fixed, and a lid member 38 for sealing the accommodating portion 27 are provided.
As shown in FIG. 1B, an example of the container 20 is formed by laminating and firing a rectangular flat plate-like first insulating substrate 20a and a flat plate-like second insulating substrate 20b. A housing portion for housing the piezoelectric vibration element 10 by the front portion of the first insulating substrate 20a and the second insulating substrate 20b having an annular body whose bottom is laminated and fixed to the front portion of the first insulating substrate 20a. A (cavity) 27 is formed.
Note that castellations C1, C2, C3, and C4 are formed on the side wall surfaces at the corners of the first insulating substrate 20a and the second insulating substrate 20b.

FIG. 2 is a schematic plan view showing the configuration of the surface of the first insulating substrate 20a used in the container 20 shown in FIG. A pair of first electrode pads 28a and 28b on which the piezoelectric vibration element 10 is mounted are juxtaposed in the short direction near one end in the longitudinal direction (lateral direction in the figure) of the surface of the first insulating substrate 20a. . FIG. 2B is a back view showing the configuration of the back surface of the first insulating substrate 20a, and mounting terminals 22 (22a, 22b, 22c, 22d) are formed at four corners of the back surface, respectively. Further, a pair of second electrode pads 29a and 29b are arranged in the center of the back surface of the first insulating substrate 20a so as to be orthogonal to the longitudinal direction (lateral direction in the figure), and the mounting terminals 22c and 22d and The second electrode pads 29b and 29a are conductively connected by the second wiring patterns 26b and 26b, respectively. Here, the front portion (front surface) of the first insulating substrate 20a is also referred to as a first main surface, and the bottom portion (bottom surface) is also referred to as a second main surface.
As shown in FIG. 1B, the second insulating substrate 20b is an annular body having a hollow central portion, and an insulating substrate in which a seal ring (not shown) is fired around the upper periphery of the annular body. It is.

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 first insulating substrate 20a. The embodiment shown in FIG. 1 will be described with reference to FIGS. Inside the thickness of the first insulating substrate 20a, there are mounting terminals 22a and 22b formed on the back surface and a pair of first electrode pads 28a and 28b for the piezoelectric vibration element 10 formed on the front surface, respectively. Via electrodes 23a and 23b are formed to be conductively connected.
That is, the mounting terminals 22a and 22b are electrically and thermally connected to the pair of first electrode pads 28a and 28b for mounting the piezoelectric vibration element 10 provided on the surface portion via the via electrodes 23a and 23b, respectively. The mounting terminals 22c and 22d are electrically and thermally connected to the pair of second electrode pads 29b and 29a for mounting the temperature sensitive component 30 provided on the back surface via the second wiring patterns 26b and 26b, respectively. Conducted.
Here, the via electrodes 23a and 23b connected to the pair of first electrode pads 28a and 28b are referred to as first heat conductive members, and the second wiring pattern 26b connected to the pair of second electrode pads 29a and 29b. , 26b is referred to as a second heat conducting member. Note that castellations C1 to C4 are formed on the side wall surfaces of the corners of the first insulating substrate 20a shown in FIGS. 2A and 2B and the second insulating substrate 20b shown in FIG. Is formed.

As shown in FIGS. 1B and 1C, the piezoelectric device 1 according to the present invention is taller than the temperature-sensitive component 30 mounted on the pair of second electrode pads 29a and 29b (first A mounting conductive member 36 (for example, a spherical, cubic or rectangular parallelepiped conductive member having a large protrusion length from the back surface of the insulating substrate 20a) is fixed to the mounting terminals 22 (22a, 22b, 22c, 22d). The height (thickness) of the mounting conductive member 36 mounted on the mounting terminal is higher (thicker) than the height (thickness) of the temperature-sensitive component 30 mounted on the mounting terminal, and the piezoelectric device 1 is mounted on the motherboard. When mounted on the board, the height (thickness) is set so that a gap is formed between the front surface of the motherboard and the back surface of the temperature-sensitive component 30 (the lower surface in FIG. 1B). It is desirable that the mounting conductive members 36 have the same height (thickness), and the container 20 is parallel (parallel) to the motherboard surface when mounted.
The mounting conductive member 36 may be formed of a metal member, or may be a conductive electrode member obtained by plating a resin member.

Predetermined terminals on the mother board are electrically connected to the mounting terminals 22a and 22b of the container 20 via the mounting conductive member 36, and are electrically connected to the pair of first electrode pads 28a and 28b via the via electrodes 23a and 23b. Connected. Further, predetermined terminals on the mother board are electrically connected to the mounting terminals 22c and 22d of the container 20 through the mounting conductive member 36, and a pair of second electrode pads through the second wiring patterns 26b and 26. 29a and 29b are conductively connected.
In the configuration procedure of the piezoelectric device 1, first, the conductive adhesive 35 is applied to the first electrode pads 28 a and 28 b of the container 20, and the piezoelectric vibration element 10 is placed thereon and lightly pressed. This is put in a drying furnace and heated at a predetermined temperature for a predetermined time, and then the upper peripheral edge of the container 20 is seam welded with a lid member 38 in a vacuum or in an inert gas atmosphere to be hermetically sealed. Configure the vibrator. Next, the temperature sensitive component 30 is mounted on the second electrode pad on the bottom surface of the container 20 of the piezoelectric vibrator and fixed with solder or the like, and the mounting conductive member 36 is fixed to the mounting terminal 22 with solder or the like, for example. The piezoelectric device 1 is configured.
If the accommodation location of the temperature-sensitive component 30 is configured on the bottom surface side of the container 20 with the bottom surface of the container 20 and the mounting conductive member 36, the configuration of the container 20 can be simplified and the cost can be reduced. Since only the child 10 is accommodated, the effects of degassing can be greatly reduced and the frequency aging characteristics are improved as compared with the case where the temperature sensitive component 30 is accommodated in the accommodating portion 27. Moreover, the height of the mounting conductive member 36 may be appropriately selected according to the thickness of the temperature-sensitive component 30, and there is an advantage that the dimensions of the container 20 need not be changed.

FIG. 3A is a plan (front) view of the first insulating substrate 20a1 used in the piezoelectric device 1 according to another example, and FIG. 3B is a back view. The difference between the first insulating substrate 20a shown in FIG. 2 and the first insulating substrate 20a1 according to another example shown in FIG. 3 is that the side surfaces of the castellations C1 to C4 are different in the insulating substrate 20a1 shown in FIG. The metal film is fired to form castellation electrodes Ce1 to Ce4. Further, on the surface of the first insulating substrate 20a1, there are formed first wiring patterns 26a and 26a for electrically connecting the pair of first electrode pads 28a and 28b and the castellation electrodes Ce1 and Ce2, respectively. On the back side, the mounting terminals 22a, 22b, 22c, 22d and the castellation electrodes Ce1, Ce2, CE3, Ce4 are different from each other. That is, the mounting terminals 22a and 22b are conductively connected to the first electrode pads 28a and 28b via the via electrodes 23a and 23b, and are also connected to the castellation electrodes Ce1 and Ce2 and the first wiring patterns 26a and 26a. This is the point of conducting connection. The mounting terminals 22c and 22d are conductively connected to the second electrode pads 29b and 29a through the second wiring pattern. The first wiring patterns 26a and 26a that are conductively connected to the pair of first electrode pads 28a and 28b are also referred to as first heat conducting members.
In other words, the heat conduction path from the mounting terminals 22a and 22b to the first electrode pads 28a and 28b includes a path that conducts via the via electrodes 23a and 23b (first heat conduction member), and a castellation electrode. There is a path that conducts via the first wiring patterns 26a and 26a (first heat conducting member) via Ce1 and Ce2.

  4A is a front view of the first insulating substrate 20a2 used in the piezoelectric device 1 according to another example, and FIG. 4B is a rear view. On the side surface of the castellation shown in FIG. 4, a metal film is baked to form castellation electrodes Ce1 to Ce4. However, the via electrode penetrating through the thick portion of the first insulating substrate 20a2 is not provided. Therefore, the electrical continuity and thermal conduction between the mounting terminals 22a and 22b and the first electrode pads 28a and 28b are performed from the mounting terminals 22a and 22b to the castellation electrodes Ce1 and Ce2 and the first wiring pattern 26a. 26a. Further, the electrical conduction and thermal conduction between the mounting terminals 22c and 22d and the second electrode pads 29b and 29a are conducted and conducted via the second wiring patterns 26b and 26b.

FIG. 5A is a front view of the first insulating substrate 20a3 used in the piezoelectric device 1 according to another example, and FIG. 5B is a rear view. A feature of the first insulating substrate 20a3 is that mounting terminals 22a and 22c for the piezoelectric vibration element 10 are diagonally arranged on the back surface of the first insulating substrate 20a3. The mounting terminals 22b and 22d for the temperature sensitive component 30 are also arranged diagonally on the back surface of the first insulating substrate 20a3. That is, the mounting terminal 22a is electrically connected to one electrode pad 28a of the first electrode pad on the surface by the via electrode 23a that penetrates the thick insulator, and the mounting terminal 22c connects the via electrode 23b that penetrates the insulator. Then, it is connected to the relay pad 40 on the surface, and is electrically connected to the other electrode pad 28b of the first electrode pad via the first wiring pattern 26a. The mounting terminals 22b and 22d are conductively connected to the second electrode pads 29b and 29a via the second wiring patterns 26b and 26b on the back surface, respectively.
Mounting terminal 22 (22a, 22b, 22c, 22d) of container 20, first heat conductive member (via electrodes 23a, 23b, first wiring pattern 26a), and second heat conductive member (second wiring) As a metal material used for the pattern 26b), for example, a tungsten material can be exemplified. Tungsten material can also be used as the metallized portion formed on the periphery of the upper surface of the second insulating substrate 20b.

In the configuration example of the piezoelectric device 1 shown in FIGS. 1 and 2, the mounting terminals 22a and 22b and the piezoelectric vibration element 10 are electrically connected via via electrodes (first heat conducting members) 23a and 23b. The mounting terminals 22c and 22d and the temperature-sensitive component 30 achieve electrical conduction and thermal conduction via the second wiring pattern (second thermal conduction member) 26b.
In the piezoelectric device 1 using the first insulating substrate 20a1 shown in FIG. 3 as the container 20, the mounting terminals 22a and 22b and the piezoelectric vibration element 10 are routed via via electrodes (first heat conducting members) 23a and 23b. Electrical conduction and thermal conduction are achieved through two paths, namely, a path that passes through the first wiring pattern via the castellation electrodes Ce1 and Ce2. The mounting terminals 22c and 22d and the temperature-sensitive component 30 achieve electrical continuity and thermal conduction via the second wiring pattern (second thermal conduction member) 26b.
Further, in the piezoelectric device 1 using the first insulating substrate 20a2 shown in FIG. 4 as the container 20, the mounting terminals 22a and 22b and the piezoelectric vibration element 10 include the castellation electrodes Ce1 and Ce2 and the first wiring pattern 26a, The electric conduction and the thermal conduction are achieved through the terminal 26a. The mounting terminals 22c and 22d and the temperature-sensitive component 30 achieve electrical continuity and thermal conduction via the second wiring pattern (second thermal conduction member) 26b.
Further, in the piezoelectric device 1 using the first insulating substrate 20a2 shown in FIG. 5 as a container, the mounting terminals 22a and 22c arranged diagonally on the back surface are via the via electrodes 23a, and the latter are vias. Through the electrode 23b, the relay pad 40, and the first wiring pattern 26a, electrical continuity and thermal conduction with the first electrode pads 28a and 28b are achieved. The mounting terminals 22b and 22d are electrically and thermally conductive by the second wiring patterns 26b and 26b.

The piezoelectric vibration element 10 used in the embodiment shown in FIG. 1 includes, for example, an AT cut crystal vibration element. 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 substrate 12 is a flat plate cut from the quartz along a plane obtained by rotating the XZ plane about 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.
That is, an example of the piezoelectric substrate 12 shown in FIG. 1 is centered on the X axis of an orthogonal coordinate system composed of an X axis (electric axis), a Y axis (mechanical axis), and a Z axis (optical axis) as shown in FIG. The Z axis is tilted in the -Y direction of the Y axis is the Z 'axis, the Y axis is tilted in the + Z direction of the Z axis is the Y' axis, and the plane is parallel to the X and Z 'axes. And 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. When the frequency is high and the X-side ratio (X / t, X is the length in the X-axis direction, t is the thickness) or the Z-side ratio (Z / t, Z is the length in the Z′-axis direction) is large In this case, a flat crystal substrate 12 is used. 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. 7 shows an example of a mesa-type crystal resonator element. FIG. 7A is a plan view and FIG. 7B is a QQ cross-sectional view.
The mesa-type quartz substrate 12 includes an excitation unit 13 that is located at the center and serves as a main vibration region, and a peripheral portion 15 that is thinner than the excitation unit 13 and that is formed along the periphery of the excitation unit 13. ,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. 7, 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. 6 (b). This is an example of the piezoelectric vibration element 10 using a mesa-type piezoelectric substrate in which a step is formed.

Excitation electrodes 14a and 14b are formed on the front and back of the excitation portion 13 of the quartz substrate 12, and lead electrodes 16a extending from the excitation electrodes 14a and 14b toward terminal electrodes 18a and 18b provided at the ends of the quartz substrate 12, 16b is formed.
When an alternating voltage is applied to the excitation electrodes 14a and 14b, the crystal resonator element 10 is excited at a specific vibration frequency (resonance frequency).
Moreover, the temperature sensitive component 30 used for the piezoelectric device 1 shown in FIG. 1 uses a thermistor or the like whose physical quantity, for example, electric resistance changes according to temperature change. The electrical resistance of the thermistor 30 can be detected by an external circuit, and the temperature detected by the thermistor 30 can be measured.

The piezoelectric device 1 according to the present invention is characterized by considering the heat capacities of the piezoelectric vibration element 10 and the temperature sensitive component 30 so that the temperature of the piezoelectric vibration element 10 and the temperature detected by the temperature sensitive component 30 are substantially equal. Each length, thickness, etc. of 1 heat conductive member (via electrode) 23a, 23b and 2nd heat conductive member (2nd wiring pattern) 26b are set appropriately. For example, the total heat capacity A including the piezoelectric vibration element 10, the conductive adhesive 35, the pair of first electrode pads 28 a and 28 b, and the first heat conductive members (via electrodes) 23 a and 23 b, the temperature sensitive component 30, The total heat capacity B including the second electrode pads 29a and 29b and the second wiring patterns 26b and 26b is set to have the same heat capacity. Since the piezoelectric vibration element 10 and the temperature-sensitive component 30 generally have different heat capacities in general, the thermal conductivity, diameter and length of the first heat conducting member and the thermal conductivity, length of the second heat conducting member are long. The thickness and width are appropriately set so that the total heat capacities A and B are equal. In other words, the types and dimensions of the members are appropriately set so that the temperature of the piezoelectric vibration element 10 and the temperature of the temperature-sensitive component 30 are substantially equal, that is, the thermal equilibrium between the two is quickly achieved. It is to be.
However, if the total heat capacity A and the total heat capacity B cannot be equal, the thermal resistance of the heat conduction path with the smaller heat capacity is increased, and the temperature of the piezoelectric vibration element 10 and the temperature of the temperature-sensitive component 30 are almost equal. It is necessary to appropriately set the thermal resistance of the heat conducting member so as to be equal.

FIG. 8A is a cross-sectional view showing a main conduction path of heat of the piezoelectric device 1, and FIG. 8B is a table showing the thermal conductivity of members used in the piezoelectric device 1. The thermal conductivity of air in the atmosphere surrounding the piezoelectric device 1 is extremely small. Further, the thermal conductivity of the ceramic material (Al ₂ O ₃ ) that mainly constitutes the container 20 is, for example, tungsten used for the first and second thermal conductive members (via electrodes 23a and 23b, second wiring pattern 26b). Compared to the thermal conductivity of (W), it is about 1/10. Therefore, most of the heat H generated from various amplifiers on the main circuit board (motherboard) is conducted from the mounting terminal 22 to the piezoelectric vibration element 10 and the temperature sensitive component 30 via the first and second heat conducting members. To do.

As a path related to the temperature rise of the piezoelectric vibration element 10, heat generated from an amplifier or the like of the main circuit board (motherboard) is transmitted to the mounting terminals 22a and 22b via the mounting conductive member 36, and the via electrodes 23a and 23b. Via the pair of first electrode pads 28a and 28b and the conductive adhesive 35, via the terminal electrodes 18b and 18a of the piezoelectric vibration element 10 and the lead electrodes 16b and 16a to the excitation electrodes 14b and 14a. The temperature of the substrate 12 is raised.
Further, as a path related to the temperature rise of the temperature sensitive component 30, the heat of the main circuit board is transmitted to the mounting terminals 22c and 22d via the mounting conductive member 36, and the second wiring pattern (second heat conduction). Member) 26b and 26b to reach the pair of second electrode pads 29b and 29a, and are conducted to the temperature-sensitive component 30 through the solder layer to increase the temperature of the temperature-sensitive component 30.
However, even if the same amount of heat is conducted to each of the piezoelectric vibration element 10 and the temperature-sensitive component 30, a difference in temperature rise occurs due to the heat capacity of both, so that the amount of heat flowing into each is set in consideration of the heat capacity of both. .
After setting the shape and size of the container 20 and the metallized materials of the first and second heat conducting members, the required heat from the mounting terminals 22 is generated according to the respective heat capacities of the piezoelectric vibration element 10 and the temperature-sensitive component 30. The diameter of the first heat conductive members (via electrodes) 23a and 23b of the first insulating substrate 20a and the second heat conductive member (second wiring pattern) 26b are It sets so that the temperature with the temperature sensitive component 30 may become substantially equal, respectively. That is, the diameter φ of the via electrodes 23a and 23b, the thickness and width of the second wiring pattern, etc. are appropriately set so that the temperature of the piezoelectric vibration element 10 and the temperature sensitive component 30 becomes substantially equal in a short time. To do.

The piezoelectric device shown in the embodiment of FIG. 1 is a first heat conducting member that conducts and connects the mounting terminal 22 and the first electrode pads 28a and 28b in consideration of the heat capacity of the piezoelectric vibration element 10 and the temperature sensitive component 30. The diameter and length of the (via electrodes 23a and 23b) and the length and width of the second heat conductive member (second wiring pattern 26b) that electrically connect the mounting terminal 22 and the second electrode pads 29a and 29b. By appropriately setting, the temperature difference between the temperature of the piezoelectric vibration element 10 and the temperature detected by the temperature-sensitive component 30 can be reduced. Further, by operating the piezoelectric vibration element 10 and the temperature-sensitive component 30 by connecting them to an external circuit, a temperature compensated piezoelectric oscillator having excellent frequency temperature characteristics and excellent frequency drift characteristics (short-term stability). There is an effect that can be realized. Moreover, there is an effect that the GPS performance of the mobile phone can be improved by improving the frequency drift characteristic (short-term stability).
In addition, for example, by using an AT-cut quartz substrate as the piezoelectric substrate, the frequency temperature characteristic of the piezoelectric device becomes an excellent third-order characteristic, and since the temperature compensation technology accumulated for a long time is utilized, a good frequency temperature characteristic can be obtained. It is done. Further, the AT-cut quartz substrate etching method has a long experience, has a good yield, and can mass-produce a small piezoelectric substrate at a high frequency.

FIG. 9 is a cross-sectional view of the piezoelectric device 2 according to the second embodiment using the first insulating substrate 20a1 shown in FIG. 3, and a heat conduction path is indicated by a white arrow on the drawing. FIG. 1 differs from the piezoelectric device 1 of FIG. 1 in addition to the first and second heat conductive members (via electrodes 23a and 23b and the second wiring pattern 26b) as shown in the first insulating substrate 20a1 of FIG. The castellation electrodes Ce1 to Ce4 are used together. That is, separately from the first and second heat conducting members, conduction from the mounting terminals 22a and 22b to the piezoelectric vibration element 10 via the castellation electrodes Ce1 and Ce2 and the first wiring patterns 26a and 26a. The heat that is taken into account. In consideration of the respective heat capacities of the piezoelectric vibration element 10 and the temperature sensitive component 30, the diameter φ of the via electrodes 23a and 23b, the first temperature so that the temperatures of the piezoelectric vibration element 10 and the temperature sensitive component 30 are substantially the same. The widths W1, W2 and the respective widths of the first and second wiring patterns 26a, 26b are appropriately set.
As a modification of the piezoelectric device 2 shown in FIG. 9, the castellation electrodes Ce <b> 1 to Ce <b> 4 and a seal ring (not shown) fired on the upper peripheral edge of the container 20 are configured to be conductively connected. In this configuration, heat conduction is conducted to the lid member 38 via the castellation electrodes Ce <b> 1 to Ce <b> 4, and the temperature of the piezoelectric vibration element 10 increases due to the radiant heat of the lid member 38. That is, the temperature equilibrium state between the piezoelectric vibration element 10 and the temperature-sensitive component 30 is accelerated.

Since there are a path through the first and second heat conducting members and a path through the castellation electrodes Ce1 and Ce2 in the path of heat transmitted from the mounting terminal 22, the flow of heat (heat conduction) The speed is high, and the temperature difference between the temperature of the piezoelectric vibration element and the temperature detected by the temperature-sensitive component can be reduced in a very short time.
By providing at least one of the first heat conducting members in the castellation, the flow of heat (heat conduction) transmitted from the mounting terminal is adjusted, and the temperature of the piezoelectric vibration element and the temperature detected by the temperature sensitive component There is an effect that the difference can be reduced.
Further, by connecting the castellation electrodes Ce1 to Ce4 and the seal ring, heat is conducted from the castellation electrodes Ce1 to Ce4 to the lid member 38, and the temperature rise of the piezoelectric vibration element 10 can be accelerated. is there.

FIG. 10A is a plan view in which the lid member of the piezoelectric device 3 of the third embodiment is omitted, FIG. 10B is a QQ sectional view, and FIG. 10C is a bottom view. It is. In the piezoelectric device 1 shown in FIG. 1, the mounting terminals 22a and 22b that are electrically connected to the piezoelectric vibration element 10 are arranged along the short side direction (vertical direction in the drawing) of the back surface of the first insulating substrate 20a. . In the piezoelectric device 3 of the embodiment shown in FIG. 10, the mounting terminals 22 a and 22 c for the piezoelectric vibration element 10 are diagonally arranged on the back surface of the first insulating substrate 20 a 3, and the mounting for the temperature sensitive component 30 is performed. The terminals 22b and 22d are different in that they are diagonally arranged on the back surface of the first insulating substrate 203.
A front view of the first insulating substrate 20a used in the piezoelectric device 3 is shown in FIG. 5A, and a rear view is shown in FIG. 5B. As shown in FIGS. 5A and 5B and FIG. 10C, the mounting terminal 22a is electrically and thermally connected to one electrode pad 28a of the first electrode pad via the via electrode 23a. Connected. The mounting terminal 22c is connected to the surface relay pad 40 via the via electrode 23b, and electrically and thermally to the other electrode pad 28b of the first electrode pad via the first wiring pattern 26a. Conductive connection. The mounting terminals 22b and 22d are electrically and thermally conductively connected to the pair of second electrode pads 29b and 29a via the second wiring patterns 26b and 26b.

In the piezoelectric device 1 of the embodiment shown in FIG. 1, the mounting terminals 22a (22b) are connected to the pair of first electrode pads 28a (28b) via the via electrodes 23a (23b), and the first electrode pads 28a are connected. Conductive connection is made to the piezoelectric vibration element 10 mounted on (28b). Further, the mounting terminal 22c (22d) is connected to the pair of second electrode pads 29b (29a) via the second wiring patterns 26b and 26b, and the mounting feeling is mounted on the second electrode pad 29b (29a). Conductive connection is made to the warm component 30.
On the other hand, in the piezoelectric device 3 of the embodiment shown in FIG. 10, the mounting terminal 22a (22c) passes through the via electrode 23a (23b) penetrating the first insulating substrate 20a3, and the via electrode 23a is directly connected to the first electrode. Connected to the electrode pad 28a, the via electrode 23b is electrically and thermally connected to the first electrode pad 28b via the relay pad 40 and the first wiring pattern 26a. The mounting terminals 22b (22d) are electrically and thermally connected to the pair of second electrode pads 29b and 29a via the second wiring pattern 26b (26b) provided on the back surface of the first insulating substrate 20a3. Conductive connection.

  FIG. 11 is a cross-sectional view showing the configuration of the piezoelectric device 4 according to the fourth embodiment. The piezoelectric device 4 is different from the piezoelectric device 1 of the embodiment shown in FIG. 1 in that a via electrode 25 (a third electrode) penetrating inside the first insulating substrate 20a4 and the second insulating substrate 20b4 is provided. A heat conducting member). As shown in FIG. 11, by connecting one end of the via electrode 25 and the mounting terminal 22c (for grounding) and connecting the other end to a seal ring (not shown), a seal ring is obtained. The lid member 38 that is resistance-welded to the ground is grounded via the mounting terminal 22c. In many cases, one terminal electrode of the temperature-sensitive component 30 is used while being grounded, and the mounting terminal 22c and the second electrode pad 29b are connected to one terminal of the temperature-sensitive component 30 by grounding the mounting terminal 22c. The electrode is grounded. Since the lid member 38 is grounded by the via electrode 25, the high frequency noise from the piezoelectric device 4 can be prevented from being emitted.

  The advantages of connecting the temperature sensitive component (thermistor) 30 and the lid member 38 in the piezoelectric device (vibrator incorporating the temperature sensitive component) are as follows. That is, since the lid member 38 and the piezoelectric vibration element 10 are close to each other, the temperature is close to the temperature distribution. The mounting terminal 22c and the temperature-sensitive component 30 are conductively connected, and the temperature of the piezoelectric vibration element 10 is determined by conductively connecting the mounting terminal 22c and the lid member 38 with the third heat conductive member (via electrode 25). It can be expected that the temperature difference with the temperature-sensitive component 30 is reduced. That is, it is estimated that the piezoelectric vibration element 10 and the temperature-sensitive component 30 approach the thermal equilibrium state in a short time. Further, when the mounting terminal to which one of the terminal electrodes of the temperature-sensitive component 30 is connected is grounded, a large amount of heat from the main circuit board is conducted from the grounded mounting terminal, so the temperature-sensitive component 30 and the lid are connected via this mounting terminal. Heat is conducted to the member 38 and the thermal equilibrium state is accelerated. Further, the shielding effect can be obtained at the same time by grounding the lid member 38. If the mounting terminal 22c connected to one terminal is connected to the temperature-sensitive component 30 with a total of four mounting terminals 22 including two mounting terminals for the temperature-sensitive component (thermistor) 30 and two mounting terminals for the piezoelectric vibration element 10. In addition, it is not necessary to provide an independent mounting terminal for grounding.

In the piezoelectric device 4 of the embodiment of FIG. 11, via electrodes 23 a and 23 b (first heat conduction member), first heat conduction paths from the mounting terminals 22 to the piezoelectric vibration element 10 and the temperature-sensitive component 30. The second wiring pattern 26b (second heat conductive member) and the via electrode 25 (third heat conductive member). As another embodiment, a piezoelectric device in which the first electrode pads 28a and 28b and the lid member 38 are conductively connected via the castellation electrodes Ce1 to Ce4 in addition to the via electrode 25 of FIG. Good. In this case, the width of the second wiring pattern connected to the second electrode pad is widened to reduce the thermal resistance. In this embodiment, the temperature equilibrium state between the piezoelectric vibrator 10 and the temperature sensitive element 30 can be expected to be faster than in the case of FIG.
In the piezoelectric device 4 of the embodiment shown in FIG. 11, the heat transmitted from the mounting terminal 22 passes through the first and third heat conducting members 23a, 23b, and 25, so the speed of the heat flow (heat conduction) is There is an effect that the temperature difference between the temperature of the piezoelectric vibration element 10 and the temperature detected by the temperature-sensitive component 30 can be reduced quickly and in an extremely short time. Also, by providing at least one of the first and third heat conducting members in the castellation as the heat conduction path, the speed of the heat flow (heat conduction) transmitted from the mounting terminal is high, and the time is extremely short. Thus, the temperature difference between the temperature of the piezoelectric vibration element and the temperature detected by the temperature sensitive component can be reduced.
In addition, the heat flow (heat conduction) transmitted from the mounting terminal 22 is provided on the first and third heat conducting members 23a, 23b and 25 provided in the thick portion of the first insulating substrate, and on the side surface of the container. Since it passes through the castellation electrode, the heat conduction speed is high, and the temperature difference between the temperature of the piezoelectric vibration element and the temperature detected by the temperature-sensitive component can be reduced in a very short time.

  12A is a cross-sectional view showing the configuration of the piezoelectric device 5 of the fifth embodiment, and FIG. 12B is a plan view of the first insulating substrate 20a5 of the container 20, and FIG. (C) is QQ sectional drawing of (b). The configuration of the piezoelectric device 5 is different from the configuration of the piezoelectric device 1 shown in FIG. 1 in that the surface of the first insulating substrate 20a5 is used as shown in FIG. 12 without using the second insulating substrate 20b shown in FIG. The thick-walled annular seal ring 42 is fired on the peripheral edge of the plate. The housing portion 27 is configured by the surface of the first insulating substrate 20a5 and the thick annular seal ring. 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. After the airtight sealing, the temperature-sensitive component 30 and the mounting conductive member 36 are fixed to the bottom of the container 20 in the same manner as in the piezoelectric device 1. The piezoelectric device 5 can be made shorter than the piezoelectric device 1.

FIG. 13 is a schematic block diagram illustrating a configuration of a digital mobile phone 100 using the piezoelectric device 6 according to the sixth embodiment. The piezoelectric device 6 uses the container 20 already described with reference to FIG. 1. The tuning fork type crystal resonator element 50 is accommodated in the accommodating portion 27, and the accommodating portion 27 is vacuumed and sealed with the lid member 38. The piezoelectric device 6 is configured by mounting the second conductive pads 36 on the second electrode pads 29 a and 29 formed on the bottom of the mounting pads 22 and fixing the mounting conductive members 36 to the mounting terminals 22.
When a user transmits his / her voice to the microphone when the user transmits voice using the digital mobile phone 100 shown in FIG. 13, the signal passes through a pulse width modulation / coding circuit and a modulator / demodulator circuit, and then 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 requirement, the piezoelectric device 6 shown in FIG. 14 is a piezoelectric device in which the tuning fork type crystal resonator element 10 is accommodated in the accommodating portion 27 of the container 20 and the temperature sensitive component 30 is mounted on the bottom of the container 20.
That is, the difference between the piezoelectric device 6 of the sixth embodiment and the piezoelectric device 1 shown in FIG. 1 is that, in the piezoelectric device 1, the piezoelectric vibration element 10 uses a thickness shear vibration element. However, the difference is that a tuning-fork type crystal vibrating element that performs bending vibration is used. The piezoelectric device 1 is suitable when a high frequency reference frequency is required, and the piezoelectric device 6 is suitable when a low frequency reference frequency is required.
By using a tuning-fork type crystal vibrating element for the piezoelectric vibrating element 10, there is an advantage that a desired low frequency can be obtained without frequency division. Further, when an electrode device is manufactured using the piezoelectric device 8, there is an effect that a reference frequency source having high stability and excellent short-term stability can be easily configured.
When an electronic device is manufactured using the piezoelectric devices 1 to 6, there is an effect that a reference frequency source having high stability and excellent short-term stability can be easily configured.

  A tuning fork type piezoelectric vibration element will be briefly described. FIG. 15A is a plan view of the tuning fork type piezoelectric vibration element 50, and FIG. 15B 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. 15 (a), the tuning fork type piezoelectric vibration element 50 includes a plurality of narrow belt-shaped vibrating arms 55a and 55b extending in parallel (parallel) to each other 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. 15B is a cross-sectional view taken along the line P-P in FIG. 15A, and is a cross-sectional view illustrating the arrangement of the excitation electrodes 60, 62, 64, and 66 formed on the vibrating arms 55 a and 55 b, respectively. 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. 16 is a diagram illustrating a configuration of the piezoelectric device 7 according to the seventh embodiment. FIG. 16A is a plan view, and FIG. 16B is a QQ cross-sectional view of FIG. The piezoelectric device 7 is different from the piezoelectric device 1 shown in FIG. 1 in that a piezoelectric material with thickness-shear vibration is formed on the surface of the first insulating substrate 20a6 and the accommodating portion 27 formed of the annular body of the second insulating substrate 20b6. The vibration element 10a and the tuning-fork type piezoelectric vibration element 10b for flexural vibration are accommodated side by side. 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 7 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.
When the piezoelectric device 9 is used, the use of an external circuit has an effect that two high-frequency and low-frequency piezoelectric oscillators are temperature-compensated and two excellent reference frequencies of high stability and short-term stability are obtained.

  FIG. 17A is a cross-sectional view showing the configuration of the piezoelectric device 8 according to the eighth embodiment. The piezoelectric device 8 includes a piezoelectric vibration element 10 for determining a frequency, an electronic element 30a having a pair of electrodes at both ends, for example, a thermistor for detecting temperature, and the piezoelectric vibration element 10 on a first main surface (front portion). And an insulating substrate 20a7 on which the electronic element 30a is mounted on the second main surface (bottom surface) opposite to the first main surface (front portion). Furthermore, the insulating substrate 20a7 has a pair of first electrode pads 28a, 28b for mounting the piezoelectric vibration element 10 on the first main surface (front portion) side, and electrons on the second main surface (bottom surface) side. A pair of second electrode pads 29a and 29b for mounting the element 30a and a plurality of mounting terminals 22 (22a, 22b, 22c and 22d) are provided. The second main surface side (bottom surface) includes a mounting conductive member 36 that is conductively fixed to the mounting terminal 22 and is taller than the electronic element 30a mounted on the second electrode pads 29a and 29b. . The mounting terminals 22a and 22b and the first electrode pads 28a and 28b are electrically and thermally connected by first heat conductive members (via electrodes) 23a and 23b. Further, the mounting terminals 22c and 22d and the second electrode pads 29a and 29b are electrically and thermally connected by a second heat conductive member (wiring pattern 26b). The lid member 38 has a metal plate pressed into a concave shape (bathtub shape). For example, the lid member 38 is bonded and fixed to a low-melting glass applied to the periphery of the first main surface (front portion) of the insulating substrate 20a7. The piezoelectric vibration element 10 is hermetically sealed.

FIG. 17B is a modified example of the piezoelectric device 8 shown in FIG. 17A, and a seal ring 42 is formed on the periphery of the first main surface (front portion), and a concave portion is formed in the seal ring 42. The lid member 38 is welded to hermetically seal the piezoelectric vibration element. Furthermore, the mounting terminal 22c, which is conductively connected to one terminal of the electronic element 30a, for example, a thermistor, and the seal ring 42 are conductively connected by the third heat conducting member 25, and the mounting terminal 22c is grounded, thereby shielding Has an effect function.
FIG. 18 is a cross-sectional view showing a configuration of the piezoelectric device 9 according to the ninth embodiment. The difference from the piezoelectric device 8 ′ of FIG. 17B is the configuration of the lid member 38. The lid member 38 in FIG. 18 is formed of an insulating material such as ceramic or glass, and the inner wall surface is metalized. The metallized surface and the mounting terminal 22c are conductively connected by the third heat conducting member 25.
17A, 17B, or 18 is effective in reducing the height and cost of the piezoelectric device, as well as the first and second heat conducting members, By appropriately setting the heat conduction member, the speed of the heat flow (heat conduction) transmitted from the mounting terminal is fast, and the temperature difference between the temperature of the piezoelectric vibration element and the temperature detected by the temperature sensitive component can be reduced in a short time. There is an effect.

1, 2, 3, 4, 5, 6, 7, 8, 8 ', 9 ... 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 ... container, 20a, 20a1, 20a2, 20a3, 20a4, 20a5, 20a6 ... first insulating substrate, 20b, 20b1, 20b2, 20b3, 20b4, 20b5, 20b6 ... second insulating substrate, 22, 22a, 22b, 22c, 22d ... mounting terminals, 23a, 23b ... first heat conducting member (via electrode), 25 ... third heat conducting member (Via electrode), 26a ... first heat conducting member (first wiring pattern), 26b ... second heat conducting member (second wiring pattern), 27 ... housing portion, 28a, 28b ... first electrode Pack 29a, 29b ... second electrode pad, 30 ... temperature sensitive part, 30a ... electronic element, 35 ... conductive adhesive, 36 ... conductive member, 38 ... lid member, 40 ... relay pad, 42 ... sealing ring, C1 , C2, C3, C4 ... Castellation, Ce1, Ce2, Ce3, Ce4 ... Castellation electrode

Claims (13)

A piezoelectric vibration element;
An electronic device having a pair of electrodes at both ends;
The piezoelectric vibration element is mounted on the first main surface,
An insulating substrate on which the electronic element is mounted on a second main surface opposite to the first main surface;
With
The insulating substrate is
A first electrode pad for mounting the piezoelectric vibration element on the first main surface side;
A second electrode pad for mounting the electronic element on the second main surface side, and a plurality of mounting terminals;
Have
The second main surface side is
A conductive member for mounting which is conductively fixed to the mounting terminal and is taller than the electronic element mounted on the second electrode pad;
With
At least one mounting terminal and the first electrode pad are electrically and thermally connected by a first heat conducting member,
The other at least one mounting terminal and the second electrode pad are electrically and thermally connected by a second heat conducting member.   The piezoelectric device according to claim 1, wherein a seal ring is provided on a peripheral edge on the first main surface side of the insulating substrate. A piezoelectric vibration element;
A temperature sensitive component that detects the temperature,
A container having an accommodating portion for accommodating the piezoelectric vibration element;
A piezoelectric device comprising:
The container is
A first electrode pad for mounting the piezoelectric vibration element on the first main surface side;
A first insulating substrate having a second electrode pad for mounting the temperature sensitive component on the second main surface side, and a plurality of mounting terminals;
An annular second insulating substrate having a bottom portion stacked and fixed to the first main surface side of the first insulating substrate to form the accommodating portion;
A conductive member for mounting that is conductively fixed to the mounting terminal and taller than the temperature-sensitive component mounted on the second electrode pad;
With
At least one mounting terminal and the first electrode pad are electrically and thermally connected by a first heat conducting member,
The other at least one mounting terminal and the second electrode pad are electrically and thermally connected by a second heat conducting member. The first main surface side is sealed by a concave lid member so as to cover the piezoelectric vibration element,
The said cover member is electrically and thermally connected with the mounting terminal connected with the said temperature sensitive component by the 3rd heat conductive member which penetrates the inside of the said container, The Claim 2 characterized by the above-mentioned. Piezoelectric device. A lid member for hermetically sealing the storage portion;
The said cover member is electrically and thermally connected with the mounting terminal connected with the said temperature-sensitive component by the 3rd heat conductive member which penetrates the inside of the said container, The Claim 3 characterized by the above-mentioned. Piezoelectric device.   6. The piezoelectric device according to claim 2, wherein at least a part of each of the first and third heat conducting members is disposed through the first insulating substrate. 7. device. The insulating substrate is
With a castellation on the side,
A metal layer is provided on the surface of the castellation,
3. At least a part of at least one of the first and third heat conducting members is connected to an arrangement in a castellation provided on an outer surface of the metal layer container. The piezoelectric device as described in any one of thru | or 5.   At least a part of one of the first and third heat conducting members is disposed through the first insulating substrate, and at least a part of the other is a castellation provided on the outer surface of the container. The piezoelectric device according to claim 2, wherein the piezoelectric device is disposed inside the piezoelectric device. Instead of the second insulating substrate, an annular metal substrate is adopted,
A lid member that hermetically seals the opening of the annular metal substrate;
The lid member is electrically and thermally connected to a mounting terminal connected to the temperature sensitive component by a third heat conducting member penetrating the inside of the container or the metal layer provided on the surface of the castellation. The piezoelectric device according to claim 1, wherein the piezoelectric device is connected. The piezoelectric substrate of the piezoelectric vibration element is centered on the X axis of an orthogonal coordinate system including an X axis as an electric axis which is a crystal axis of quartz, a Y axis as a mechanical axis, and a Z axis as an optical axis. As
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,
10. The piezoelectric device according to claim 1, wherein the piezoelectric device is an AT-cut quartz crystal resonator element using a quartz substrate having a side parallel to the Z ′ axis as a short side.   The piezoelectric device according to claim 1, wherein the piezoelectric vibration element is a tuning fork type crystal vibration element.   The piezoelectric vibration element is characterized in that an AT-cut crystal vibration element and a tuning-fork type crystal vibration element are juxtaposed in the housing portion.   An electronic apparatus comprising the piezoelectric device according to any one of claims 1 to 12.

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