JP2010166346A - Temperature-controlled piezoelectric oscillator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a temperature-controlled piezoelectric oscillator for stabilizing a frequency to a change in ambient temperature by using a temperature sensitive element and a heating means. <P>SOLUTION: In the constant temperature type crystal oscillator 1, a crystal oscillator 30, a heating element 40 for heating the crystal oscillator 30 to keep it at predetermined temperature, and the temperature sensitive element 45 for detecting temperature in the vicinity of the crystal oscillator 30 are connected to a leadframe composed of a plurality of metal leads 51, and the crystal oscillator 30, the heating element 40 and the temperature sensitive element 45 are resin-sealed by a pat of mold resin 91 by using a transfer mold method. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

The present invention relates to a piezoelectric oscillator used as a frequency control device and the like, and in particular, a constant temperature device capable of stabilizing a frequency against a change in ambient temperature by using a temperature control element such as a temperature sensing element or a heating element. The present invention relates to a piezoelectric oscillator.

As a piezoelectric oscillator such as a crystal oscillator that is a frequency control device used in mobile communication equipment and transmission communication equipment, there is a constant temperature type piezoelectric oscillator that can output a highly stable frequency without being affected by temperature changes in the surrounding environment. Conventionally known. In recent years, in these fields,
Since various devices are required to be small and light, the thermostatic piezoelectric oscillator is also required to be small and light in the market.
As a small constant temperature type piezoelectric oscillator that meets such requirements, for example, Patent Document 1 discloses a package type in which a piezoelectric vibrator, a heating element, a temperature sensing element, and an oscillation circuit are arranged on a substrate provided in a package. Constant temperature type piezoelectric oscillator has been introduced.

The piezoelectric oscillator (crystal oscillator) described in Patent Document 1 is provided with a heating element (heating means) along, for example, a peripheral edge of a substrate provided in a package for the piezoelectric oscillator, and in a region surrounded by the heating element. In addition, an oscillation circuit unit including a piezoelectric vibrator, a temperature sensing element, and an integrated circuit is disposed.
Here, as the heating element, for example, a heater composed of a belt-like resistance heating layer is used,
Further, as a piezoelectric vibrator, a so-called S in which a piezoelectric vibrating piece is sealed in a package for a piezoelectric vibrator.
MD (Surface Mount Device) type piezoelectric vibrators (quartz crystal vibrators) are used, which are effective in reducing size and thickness, respectively. A thermostatic piezoelectric oscillator in which a piezoelectric vibrator is sealed in a package for a piezoelectric oscillator is configured by joining a lid (cover) made of metal to the upper side of the package for the piezoelectric oscillator.

JP 2006-14208 A

However, in the constant temperature piezoelectric oscillator described in Patent Document 1, a piezoelectric vibrator disposed on a substrate and a heating element that heats the piezoelectric vibrator so as to keep the temperature constant.
Since it is exposed to the surrounding atmosphere, it is easily affected by the surrounding temperature.
In addition, since heating is performed by transferring heat from the heating element to the piezoelectric vibrator through the substrate, heating efficiency is not good, so there is a possibility that power consumption increases or stable temperature control cannot be performed. It was.
In addition, since circuit elements such as an oscillation circuit section that generates heat during operation are arranged in the vicinity of the piezoelectric vibrator, heat generated from the circuit elements such as the oscillation circuit section adversely affects the temperature control of the piezoelectric vibrator, Conversely, the temperature of the piezoelectric vibrator and the heating body that heats the piezoelectric vibrator may adversely affect the operation of the oscillation circuit unit and the like.
Further, in a constant temperature type piezoelectric oscillator using a small SMD type crystal resonator, there is a possibility that a frequency shift due to thermal damage, which was not a problem with a large volume piezoelectric resonator, may become a problem.

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 constant temperature piezoelectric oscillator according to this application example includes a substrate, a piezoelectric vibrator bonded to the substrate, and a piezoelectric vibrating piece bonded and sealed in a package, and heating the piezoelectric vibrator. A heating element that is disposed in the vicinity of the piezoelectric vibrator, and the piezoelectric vibrator, the heating element, and the temperature sensitive element are encapsulated in a single mold resin. It is characterized by being.

According to this configuration, the piezoelectric vibrator, the heating element used to heat the piezoelectric vibrator to a certain temperature, and the temperature sensitive element are integrally heated by the mold resin. It is formed. Since the heating body covered with the mold resin has a large heat capacity as compared with the case where there is no mold resin, the heating of the piezoelectric vibrator can be performed efficiently and stably. Therefore, it is possible to provide a small-sized constant temperature type piezoelectric oscillator that can heat the piezoelectric vibrator with low power consumption and has stable frequency characteristics without being affected by ambient temperature changes.

Application Example 2 In the constant temperature piezoelectric oscillator according to the application example, a lead frame including a plurality of metal leads is used as the substrate, and the resin sealing is performed with the molding resin using a transfer mold. It is characterized by.

According to this configuration, it is possible to efficiently manufacture a large number of small constant temperature type piezoelectric oscillators having stable frequency characteristics without being influenced by the ambient temperature.

Application Example 3 The constant temperature piezoelectric oscillator according to the application example is characterized in that the piezoelectric vibrator and the heating element are respectively disposed on both surfaces of the same metal lead of the lead frame.

According to this configuration, since the piezoelectric vibrator and the heating element are vertically arranged via one metal lead of the lead frame, the heat from the heating element is easily conducted to the piezoelectric vibrator, thereby improving efficiency. Heating can be achieved, and the constant-temperature piezoelectric oscillator can be reduced particularly in the plane size.

Application Example 4 A constant temperature piezoelectric oscillator according to this application example includes a substrate, a piezoelectric vibrator bonded to the substrate, and a piezoelectric vibrating piece bonded and sealed in a package, and heating the piezoelectric vibrator. A heating element that performs heating, a temperature sensing element disposed in the vicinity of the piezoelectric vibrator, and a temperature control circuit unit that controls the heating of the piezoelectric vibrator to a desired temperature by controlling the heating element and the temperature sensing element And an oscillation circuit unit, wherein the base material of the substrate is made of a non-metallic material such as a resin, and the piezoelectric vibrator, the heating element, and the temperature sensitive element are provided on one surface side of the substrate. The temperature control circuit unit and the oscillation circuit unit are disposed on the other surface side of the substrate, and the piezoelectric vibrator, the heating element, and the temperature sensitive element are placed in a single mold resin. It is resin-sealed.

According to this configuration, the piezoelectric vibrator, the heating element, and the temperature sensing element are integrally covered with the mold resin, so that one heating body having a large heat capacity is formed, and the temperature control circuit unit and the oscillation circuit are formed. The part is disposed on the opposite side of the heating body via a substrate made of a non-metallic material such as resin. That is, the temperature control circuit unit and the oscillation circuit unit that generate heat during operation are disposed outside the mold of the heating body, and the substrate made of a nonmetallic material such as a resin has a relatively low thermal conductivity, so that the heat insulating material As a result, the heating body can perform stable temperature control without being affected by heat during operation of the temperature control circuit unit and the oscillation circuit unit.
Therefore, the temperature control circuit unit, the oscillation circuit unit, and the like are integrally incorporated, and the piezoelectric vibrator can be stably heated, so that it has a stable frequency characteristic without being affected by changes in the ambient temperature. A small-sized and highly functional constant temperature piezoelectric oscillator can be provided.

Application Example 5 In the constant temperature piezoelectric oscillator according to the application example, a package is formed on the other surface side of the substrate, and the temperature control circuit unit and the oscillation circuit unit are hermetically sealed in the package. It is characterized by.

According to this configuration, the heating element in which the piezoelectric vibrator, the heating element, and the temperature sensing element are arranged in a single mold, and the temperature control circuit unit and the oscillation circuit unit are arranged vertically via the substrate. Therefore, heat from the heating element is easily conducted to the piezoelectric vibrator, so that efficient heating can be achieved, and the constant temperature type piezoelectric oscillator can be reduced particularly in a plane size.

Application Example 6 The constant temperature type piezoelectric oscillator according to the application example described above is characterized in that resin molding is performed with the molding resin using a transfer mold.

According to this configuration, the temperature control circuit unit and the oscillation circuit unit are integrally incorporated, and a large number of small and high-performance constant-temperature piezoelectric oscillators having stable frequency characteristics without being affected by the surrounding temperature are collectively included. And can be manufactured efficiently.

Hereinafter, a constant temperature crystal oscillator as one embodiment of a constant temperature piezoelectric oscillator will be described with reference to the drawings.

(First embodiment)
1 to 4 schematically illustrate the constant temperature crystal oscillator according to the present embodiment.
1 is a plan view seen from the upper side, FIG. 2 is a sectional view taken along line AA in FIG. 1, FIG. 3 is a sectional view taken along line BB in FIG. 1, and FIG. In FIGS. 1 and 4, for convenience of explanation of the internal configuration of the constant-temperature crystal oscillator, a part of the mold resin that forms the external shape of the constant-temperature crystal oscillator is notched.
FIGS. 5A and 5B illustrate a crystal resonator as a piezoelectric resonator used in the constant temperature crystal oscillator according to the present embodiment. FIG. 5A is a plan view, and FIG. 5B is a CC view of FIG. It is line sectional drawing.
Note that, in (a), for the sake of convenience in explaining the internal configuration of the crystal resonator, a part of the lid 29 bonded to the upper portion of the crystal resonator is cut out.

〔Crystal oscillator〕
First, the crystal resonator 30 provided in the constant temperature crystal oscillator 1 will be described in detail.
As shown in FIG. 5, a so-called SMD type crystal resonator 30 in which a quartz crystal resonator element 10 as a piezoelectric resonator element is bonded and sealed in a package 20 is connected to the constant temperature crystal oscillator 1 of the present embodiment.
Is used.
Since the SMD type crystal resonator 30 is becoming smaller and thinner, the constant temperature crystal oscillator 1
This is advantageous for reducing the size and thickness. SM standardized as surface mount components
The D-type crystal unit 30 is connected to an external substrate with a lead wire for external connection like a crystal unit that is sealed by covering a crystal resonator element bonded to a substrate with a cylindrical cap, for example. There is no need to cut or mold to match the terminal shape, and it is easy to automate mounting on an external substrate, which is advantageous for simplification of the mounting process and cost reduction.

In FIG. 5A, the quartz crystal resonator element 10 of the present embodiment is provided with an excitation electrode 15 as a driving electrode at the approximate center of one main surface of a quartz substrate formed in a rectangular flat plate shape. It is connected to an external connection electrode 16a provided in the vicinity of one end side of the substrate. Similarly, the other main surface of the quartz base material is provided with an excitation electrode (not shown, hidden under the excitation electrode 15) that is the opposite electrode of the excitation electrode 15, near the one end side of the quartz substrate. It is connected to an external connection electrode 16b provided in a different area from the external connection electrode 16a.

The electrodes such as the excitation electrode 15 and the external connection electrodes 16a and 16b are formed by etching or crystal deposition on the quartz substrate (quartz wafer), and then, for example, nickel (Ni) or chromium by evaporation or sputtering. It can be formed by using (Cr) as a base layer, forming a metal film of, for example, gold (Au) thereon, and then patterning using photolithography.

The package 20 includes a substantially rectangular flat first layer substrate 21, a substantially rectangular frame-shaped second layer substrate 22, a third layer substrate 23, and a seal ring 2 that are sequentially stacked on the first layer substrate 21.
8. With such a configuration, the package 20 is formed with a recess that is open to the second layer substrate 22 and the third layer substrate 23 side with the upper surface side of the first layer substrate 21 as a recessed bottom portion.

A plurality of resonator element connecting terminals 26a and 26b to which the crystal resonator element 10 is bonded are provided on the shelf portion of the second layer substrate 22 that forms a step on the first layer substrate 21 that is the concave bottom portion of the recess of the package 20. Is provided. Further, as shown in FIG. 5B, a plurality of mounting terminals 25a and 25b to be mounted on the external mounting board are provided on the lower surface side of the first layer substrate 21 which is the outer bottom surface of the package 20. Each of the resonator element connecting terminals 26a and 26b and the mounting terminals 25a and 25b are connected to each other by an inner wiring such as a lead wiring or a through hole (not shown) formed on the first layer substrate 21. ing.

The first layer substrate 21, the second layer substrate 22, and the third layer substrate 23 of the package 20 are
Made of ceramic insulating material. Further, the resonator element connecting terminals 26a and 26b and the mounting terminals 25a and 25b provided in the package 20, or the wiring pattern or the wiring pattern in the layer connecting them are generally made of tungsten (W), molybdenum (Mo), or the like. Metal wiring material is screen printed on ceramic insulating material and fired.
It is formed by performing plating such as Ni) or gold (Au).

The quartz crystal vibrating piece 10 has an external connection electrode 16a provided in the vicinity of one end side of the quartz crystal vibrating piece 10.
16b and the corresponding resonator element connecting terminals 2 provided on the second layer substrate 22 of the package 20.
In a state where 6a and 26b are aligned with each other, they are joined by a joining member such as a conductive adhesive 95, for example. As a result, the quartz crystal resonator element 10 is cantilevered in a state where there is a gap so as not to contact the first layer substrate 21 with the opposite side of the external connection electrodes 16a and 16b joined to the package 20 as a free end. Yes.
In general, the conductive adhesive 95 is made of a resin such as polyimide, silicon, or epoxy mixed with silver (Ag) filament or nickel (Ni) powder. Further, the bonding member for bonding the quartz crystal vibrating piece 10 is not limited to the conductive adhesive 95, and other bonding members such as solder can be used.

On the third layer substrate 23 of the package 20 to which the crystal vibrating piece 10 is bonded, a lid 29 as a lid is bonded. In the present embodiment, the metal lid 29 is made of iron-nickel (F
e-Ni) is seam welded through a seal ring 28 formed by punching an alloy or the like into a frame shape. As a result, the crystal vibrating piece 10 bonded in the recess of the package 20 is hermetically sealed.

[Constant temperature crystal oscillator]
Next, the constant temperature crystal oscillator 1 including the crystal resonator 30 will be described.
As shown in FIGS. 1 to 4, the constant temperature crystal oscillator 1 of the present embodiment includes a plurality of metal leads 51.
A crystal frame 30 as a piezoelectric vibrator, a heating element 40 for heating the crystal vibrator 30 to a predetermined temperature, and a temperature sensing device for detecting the temperature in the vicinity of the crystal vibrator 30. The element 45 is bonded to each other, and the crystal unit 30, the heating element 40, and the temperature sensitive element 45 are resin-sealed in a lump of mold resin 91 using a transfer mold.

The plurality of metal leads 51 of the lead frame support an internal connection terminal 53 or an element connected to each element constituting the constant temperature crystal oscillator 1 on one end side disposed in the mold resin 91. The support terminal portion 52 is connected to the internal connection terminal 53 or the other end portion of the support terminal portion 52 and is molded into a predetermined shape outside the mold resin 91 and used for bonding to the external substrate of the constant temperature crystal oscillator 1. The mounting terminal portion 55 (details will be described later).

As shown in FIG. 1, on the upper surface of the lead frame, a crystal unit 30 and a temperature sensitive element 45 are provided.
Are joined. More specifically, in the state in which the mounting terminals 25a and 25b of the crystal resonator 30 and the internal connection terminals 53 of the corresponding metal leads 51 are aligned, the crystal vibration is provided on the support terminal portion 52 of another metal lead 51. It arrange | positions so that the child 30 may be supported and the mounting terminal 25a
, 25b and the corresponding internal connection terminal 53 are electrically connected. This mounting terminal 25a,
25b and the internal connection terminal 53 are joined through, for example, a not-shown joining member such as a conductive adhesive or solder. In the present embodiment, in order to position the crystal resonator 30 on the lead frame in the mounting step, as shown in FIG. 2, the support terminal portion 52 and the crystal resonator 30 are insulative adhesive 98. It is bonded and fixed by etc.

Further, in the vicinity of the crystal resonator 30, a temperature sensitive element 45 connected to the internal connection terminal 53 of the metal lead 51 different from the metal lead 51 connected to the crystal resonator 30 is arranged. As the temperature sensing element 45, the specific resistance changes relatively greatly as the temperature rises, for example, p
An SMD type thermistor element made of a type semiconductor oxide can be used.

The heating element 40 is disposed on the lower surface of the lead frame different from the surface on which the crystal resonator 30 and the temperature sensitive element 45 are disposed. In the present embodiment, the heating element 40 is in close contact with and bonded to the opposite surface of the support terminal portion 52 of the metal lead 51 on which the crystal resonator 30 is supported, and as shown in FIG. A plurality of electrode pads 41 provided on the surface opposite to the surface joined to the support terminal portion 52 and the internal connection terminals 53 of the corresponding metal leads 51 are connected by bonding wires 97.

The crystal resonator 30, the temperature sensitive element 45, and the heating element 40 bonded to the lead frame as described above are integrally sealed with the mold resin 91. In such resin sealing, a lead frame in which the crystal resonator 30, the temperature sensitive element 45, and the heating element 40 are joined is fixed inside a transfer mold cavity, and a thermosetting mold resin 91 is injection molded. Is performed by filling the mold resin 91 into the cavity,
Thereby, the constant temperature crystal oscillator 1 which is an integrated resin package is formed.

In the thermostat crystal oscillator 1 sealed with resin, a plurality of metal leads 51 of a lead frame are provided.
The portions exposed to the outside from the mold resin 91 are each formed into a predetermined shape to form a mounting terminal portion 55 for mounting on an external substrate. Specifically, each metal lead extending in the horizontal direction from the internal connection terminal 53 or the support terminal portion 52 inside the mold resin 91 to which the crystal resonator 30, the temperature sensitive element 45, and the heating element 40 are joined. 5
1 is bent in a substantially vertical direction at a slight length after coming out of the mold resin 91, and is bent substantially horizontally inward of the thermostatic crystal oscillator 1 below the bottom surface of the outer shape of the mold resin 91. Thus, the substantially horizontal other end portion of the metal lead 51 is a mounting terminal portion 55 (
(See FIG. 3).
In the constant temperature crystal oscillator 1 of the present embodiment, the other end side of each metal lead 51 of the lead frame is bent inwardly of the constant temperature crystal oscillator 1 to form the mounting terminal portion 55, thereby forming the constant temperature crystal. An example for reducing the size of the oscillator 1 has been described. However, the present invention is not limited to this, and a plurality of metal leads 51 may be bent horizontally in the outer direction of the constant temperature crystal oscillator 1 and used as a mounting terminal portion.

According to the constant temperature crystal oscillator 1 of the first embodiment, the crystal resonator 30, the temperature sensitive element 45, and the heating element 40 bonded to the lead frame are integrally encapsulated in a lump of mold resin 91. It has been stopped.
As a result, the crystal resonator 30 and the heating element 40 and the temperature sensitive element 45 used for heating the crystal resonator 30 to a certain temperature are integrally heated by the mold resin 91. A body is formed, and this heating body has a large heat capacity as compared with the case where there is no mold resin 91, so that it is possible to efficiently and stably heat and maintain the temperature. Accordingly, it is possible to provide a small-sized constant temperature crystal oscillator 1 that can efficiently heat the crystal unit 30 with low power consumption and has a stable frequency characteristic without being affected by a change in ambient temperature. it can.

The constant temperature crystal oscillator 1 of the first embodiment includes a crystal resonator 30 and a heating element 40.
In addition, a lead frame is used as a substrate to which the temperature sensitive element 45 is bonded, and the mold resin 9
1 was filled by a transfer molding method and resin molded.
As a result, a large number of small thermostatic crystal oscillators 1 having stable frequency characteristics without being affected by the ambient temperature can be efficiently manufactured collectively.

In the constant temperature crystal oscillator 1 of the first embodiment, the crystal resonator 30 and the heating element 4 are used.
0 were arranged on different surfaces of the support terminal portion 52 of the same metal lead 51 of the lead frame.
As a result, the crystal unit 30 and the heating element 40 are vertically arranged with the support terminal portion 52 made of metal interposed therebetween, so that the heat from the heating unit 40 is efficiently transmitted to the crystal unit 30 and the heating efficiency is increased. As a result, the constant-temperature crystal oscillator 1 can be reduced in size especially in a plane size.

(Second Embodiment)
The constant-temperature crystal oscillator 1 described in the first embodiment can also be provided as a higher-performance constant-temperature crystal oscillator by further incorporating an oscillation circuit unit or the like.
FIG. 6 schematically illustrates a high-performance constant-temperature crystal oscillator in which an oscillation circuit unit, a temperature control circuit unit, and the like are integrated, wherein (a) is a plan view seen from above, and (b) is a plan view. D- in (a)
D line sectional drawing, (c) is the top view seen from the bottom face side. In FIG. 6A, for convenience of explanation of the internal configuration of the constant-temperature crystal oscillator, a part of the mold resin that forms the outer shape of the constant-temperature crystal oscillator is cut out. In addition, among the configurations of the constant temperature crystal oscillator 101 of the present embodiment, the same components as those of the first embodiment are denoted by the same reference numerals and description thereof is omitted.

6B, the constant temperature crystal oscillator 101 has a package 120 in which a concave portion is formed with a first layer substrate 121 as a substrate having circuit wirings formed on both sides thereof as a bottom plate.
A temperature control circuit element 60 serving as a temperature control circuit unit and an oscillation circuit serving as an oscillation circuit unit are provided on one surface (the upper and lower surfaces of the sheet) of the first layer substrate 121 serving as a concave bottom portion of the recess of the package 120. The element 70 is joined.
Further, the SMD type crystal resonator 30, the heating element 40, and the temperature sensing element 45 are bonded to the other surface (the upper surface on the paper surface) of the first layer substrate 121. The heating element 40 and the temperature sensitive element 45 are resin-sealed by a lump of mold resin 91.

The package 120 includes a first layer substrate 121 in which circuit wiring is formed on both sides of a substantially rectangular flat substrate, and a substantially rectangular frame-shaped second layer substrate 122 laminated on the first layer substrate 121. As a result, a recess having one surface of the first layer substrate 121 as a recessed bottom portion is formed. A plurality of temperature control circuit element connection terminals 152a to which the temperature control circuit element 60 is bonded are formed on one surface of the first layer substrate 121, which is a concave bottom portion of the recess of the package 120, and for the oscillation circuit An element connection terminal 152b is provided. In addition, the first which becomes the outer bottom surface of the package 120
On the other surface of the layer substrate 121, the crystal unit 30, the heating element 40, and the temperature sensitive element 45 are provided.
An element internal connection terminal 153 is provided for connection to the.
In the package 120 of this embodiment, a material having a relatively low thermal conductivity such as a resin such as an epoxy resin or a ceramic material is used as a material of at least the first layer substrate 121. This is because, as described above, a heating body in which the crystal resonator 30, the heating element 40, and the temperature-sensitive element 45 disposed above and below the first layer substrate 121 are integrally sealed with the mold resin 91. And the heat insulating layer between the temperature control circuit element 60 and the oscillation circuit element 70 joined in the package 120.

6B and 6C, the temperature control circuit element 60 and the oscillation circuit element 70 are bonded to the surface of the first layer substrate 121 which is the bottom of the recess of the package 120. . Specifically, the plurality of connection electrodes 65 provided in the temperature control circuit element 60 and the corresponding temperature control circuit element connection terminal 152a are aligned, and the plurality of connections provided in the oscillation circuit element 70 are also aligned. The electrode 75 and the oscillation circuit element connection terminal 152b are aligned,
Each of them is joined via a joining member such as a conductive adhesive or solder (not shown).

Further, in the package 120, a lid 129 is joined to the opening side of the recess formed by the substantially rectangular frame-shaped second layer substrate 122. As a result, the temperature control circuit element 60 and the oscillation circuit element 70 joined in the package 120 are sealed.
The outer surface of the lid 129 (the lower surface in FIG. 6B) is the bottom surface of the constant temperature crystal oscillator 101 of the present embodiment, and the constant temperature crystal oscillator 101 is on the bottom surface side. A plurality of mounting terminals 155a to 155f used for bonding between the external mounting board and the external mounting board are provided (FIG. 6 (
See also c)). These mounting terminals 155a to 155f correspond to the plurality of element internal connection terminals 153, the temperature control circuit element connection terminal 152a, and the oscillation circuit element connection terminal 152b, respectively. The wirings are connected by an intra-layer wiring such as a routing wiring or a through hole (not shown) formed in the package 120.

As shown in FIGS. 6A and 6B, on the bottom surface of the first layer substrate 121 of the package 120, the crystal unit 30 and a temperature sensitive element disposed in the vicinity of the crystal unit 30. 45 is joined. Specifically, the mounting terminals 25a and 25b of the crystal unit 30 and the temperature sensitive element 4
5 electrodes (not shown) and the element internal connection terminals 15 of the first layer substrate 121 corresponding to the respective electrodes.
3 are aligned and joined via a joining member (not shown) such as a conductive adhesive or solder.
A heating element 40 is disposed above the crystal unit 30. In this embodiment,
A heating element 40 is fixed in close contact with the upper surface of the crystal resonator 30 via a non-conductive adhesive (not shown), and a plurality of electrode pads 41 provided on the main surface of the heating element 40; A corresponding element internal connection terminal 153 of the first layer substrate 121 is connected by a bonding wire 97.

As described above, the crystal resonator 30, the temperature sensitive element 45, and the heating element 40 bonded to the bottom surface of the first layer substrate 121 of the package 120 are integrated by the molding resin 91 by transfer molding. It is sealed with resin.

According to the constant temperature crystal oscillator 101 of the second embodiment, the heating element in which the crystal unit 30, the heating element 40, and the temperature sensing element 45 are integrally sealed with the mold resin 91, and the package 120 The temperature control circuit element 60 and the oscillation circuit element 70 joined to each other
They are arranged above and below the first layer substrate 121 made of a material having a relatively low thermal conductivity.
The piezoelectric vibrator, the heating element, and the temperature sensing element are integrally covered with the mold resin, so that one heating body having a large heat capacity is formed, and the temperature control circuit unit and the oscillation circuit unit are made of resin. It arrange | positions through the board | substrate on the opposite side of the said heating body. Thereby, the influence of the heat of the temperature control circuit element 60 and the oscillation circuit element 70 that generate heat during operation on the heating element can be suppressed. Conversely, the influence of the heat of the heating body on the circuit bodies such as the temperature control circuit element 60 and the oscillation circuit element 70 can be suppressed. Accordingly, it is possible to provide a small constant temperature crystal oscillator 101 having a built-in circuit body such as the temperature control circuit element 60 and the oscillation circuit element 70 and having stable frequency characteristics without being affected by ambient temperature changes. it can.

The embodiment of the present invention made by the inventor has been specifically described above, but the present invention is not limited to the above-described embodiment, and various modifications are made without departing from the scope of the present invention. Is possible.

For example, in the first and second embodiments, the resin sealing of the crystal resonator 30, the heating element 40, and the temperature sensitive element 45 is performed by the transfer molding method. However, the present invention is not limited to this, and by adjusting the viscosity or the like of the mold resin 91, the resin can be sealed by applying the mold resin by a so-called potting method.

In the first embodiment, an example in which a lead frame is used as a substrate has been described in view of the convenience of using resin sealing by transfer molding. However, the present invention is not limited to this, and the substrate may be a circuit board in which circuit wiring is formed on both surfaces of a base material such as resin.

Moreover, in the said 2nd Embodiment, the 1st layer board | substrate 121 as a board | substrate which functions as a heat insulation layer.
A heating body in which the crystal unit 30, the heating element 40, and the temperature sensing element 45 are integrally resin-sealed, a temperature control circuit element 60, and an oscillation circuit element 70.
The circuit body is configured to be thermally shielded. However, the present invention is not limited to this. For example, a double-sided wiring board other than the package may be used as long as the heating body and the circuit body can be thermally shielded via a substrate that can be a heat insulating layer.

In the above embodiment, the constant temperature crystal oscillators 1 and 101 having the crystal resonator 30 using the crystal resonator element 10 as the piezoelectric resonator element have been described. In addition to quartz, aluminum nitride (AlN), lithium niobate (LiNbO ₃ ), lithium tantalate (
LiTaO ₃ ), lead zirconate titanate (PZT), lithium tetraborate (Li ₂ B ₄ O ₇ ) and other oxide substrates, and glass substrates on aluminum nitride and tantalum pentoxide (Ta ₂ O ₅ ) thin films A piezoelectric vibrating piece made of a piezoelectric material formed by laminating piezoelectric materials can also be used.

Further, the crystal resonator 30 and the package 20 and the package 120 constituting the circuit body of the first and second embodiments are not limited to those having the laminated structure described in the above embodiment, and are integrated by machining or the like. You may use the thing of the shape.

The top view which illustrates typically the constant temperature type crystal oscillator as 1st Embodiment of a constant temperature type piezoelectric oscillator seeing from an upper side. FIG. 2 is a cross-sectional view taken along the line AA in FIG. 1 for schematically explaining the constant temperature crystal oscillator according to the first embodiment. The BB sectional drawing of FIG. 1 which illustrates the constant temperature type crystal oscillator of 1st Embodiment typically. The top view which illustrates typically the constant temperature type crystal oscillator of 1st Embodiment seeing from the bottom face side. (A) is a top view which illustrates typically the crystal oscillator as a piezoelectric vibrator, (b) is CC sectional view taken on the line of (a). (A) is a top view which illustrates typically the constant temperature crystal oscillator of 2nd Embodiment seeing from an upper side, (b) is the DD sectional view taken on the line of (a), (c) is a bottom face side. FIG.

DESCRIPTION OF SYMBOLS 1,101 ... Constant temperature crystal oscillator as a constant temperature type piezoelectric oscillator, 10 ... Quartz vibration piece as a piezoelectric vibration piece, 15 ... Excitation electrode, 16a, 16b ... External connection electrode, 20, 120 ... Package, 21, 121 ... First 1st layer substrate, 22, 122 ... 2nd layer substrate, 23 ... 3rd layer substrate, 25a
, 25b ... mounting terminals, 26a, 26b ... vibrating piece connection terminals, 28 ... seal ring, 29 ... lid as lid, 30 ... crystal resonator as piezoelectric vibrator, 40 ... heating element, 41 ... electrode pad, 45 ... temperature sensing element, 51 ... metal lead, 52 ... support terminal part, 53 ... internal connection terminal, 55 ... mounting terminal part, 60 ... temperature control circuit element as temperature control circuit part, 65 ... connection electrode, 70 ... Oscillation circuit element as an oscillation circuit unit, 91 ... Mold resin, 95 ... Conductive adhesive, 97 ... Bonding wire, 129 ... Lid, 152a ... Temperature control circuit element connection terminal, 152b ... Oscillation circuit element connection terminal , 153 ... Element internal connection terminals, 155a to 155
f: Mounting terminal.

Claims (6)

A substrate,
A piezoelectric vibrator bonded to the substrate and having a piezoelectric vibrating piece bonded and sealed in a package;
A heating element for heating the piezoelectric vibrator;
A temperature-sensitive element disposed in the vicinity of the piezoelectric vibrator,
A constant temperature piezoelectric oscillator, wherein the piezoelectric vibrator, the heating element, and the temperature sensitive element are sealed in a single mold resin. The constant temperature piezoelectric oscillator according to claim 1,
A lead frame made of a plurality of metal leads is used as the substrate,
A constant temperature piezoelectric oscillator, wherein a transfer mold is used to seal the resin with the mold resin. The constant temperature piezoelectric oscillator according to claim 2,
The constant temperature type piezoelectric oscillator, wherein the piezoelectric vibrator and the heating element are respectively disposed on both surfaces of the same metal lead of the lead frame. A substrate,
A piezoelectric vibrator bonded to the substrate and having a piezoelectric vibrating piece bonded and sealed in a package;
A heating element for heating the piezoelectric vibrator;
A temperature sensing element disposed in the vicinity of the piezoelectric vibrator;
A temperature control circuit unit for controlling the heating of the piezoelectric vibrator to a desired temperature by controlling the heating element and the temperature sensitive element;
An oscillation circuit unit,
The base material of the substrate is made of a non-metallic material such as a resin,
The piezoelectric vibrator, the heating element, and the temperature sensitive element are disposed on one surface side of the substrate,
The temperature control circuit unit and the oscillation circuit unit are disposed on the other surface side of the substrate,
A constant temperature piezoelectric oscillator, wherein the piezoelectric vibrator, the heating element, and the temperature sensitive element are sealed in a single mold resin. The constant temperature piezoelectric oscillator according to claim 4,
A package is formed on the other side of the substrate;
The thermostatic piezoelectric oscillator, wherein the temperature control circuit unit and the oscillation circuit unit are hermetically sealed in the package. The piezoelectric oscillator according to claim 4 or 5,
A constant temperature piezoelectric oscillator, wherein a transfer mold is used to seal the resin with the mold resin.

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