JP2011160173A - Piezoelectric vibrator and piezoelectric oscillator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a piezoelectric vibrator, and a piezoelectric oscillator capable of sharply reducing amplitude of a free end of a piezoelectric vibration element by an impact to prevent collision with the lid without passing through such a complicated operation as to finely adjust a gap with a lid when the piezoelectric vibration element is mounted in order to solve a fault that the free end of the piezoelectric vibration element vibrates in the thickness direction, collides with the lid to be damaged by application of the impact. <P>SOLUTION: The piezoelectric vibrator includes: a circuit board 2 which has an element mounting pad 7 at an upper part and has a mounting electrode 10 at a lower part; the piezoelectric vibration element 20, one end of which is fixed on the element mounting pad; and the lid 11 which surrounds a space on the circuit board including the piezoelectric vibration element; and a wire 30, both ends of which are fixed to the circuit board so as to cross at least a part of an upper surface of the piezoelectric vibration element. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

The present invention relates to an improvement of a surface mount type piezoelectric device such as a piezoelectric vibrator having a structure in which a piezoelectric vibration element is cantilevered, and the free end portion of the piezoelectric vibrator vibrates due to an impact generated when dropped, etc. The present invention relates to a piezoelectric vibrator and a piezoelectric oscillator that can prevent collision with a lid to be closed.

A piezoelectric vibration element such as a crystal vibration element is used by being incorporated in a piezoelectric vibrator, a piezoelectric oscillator, or the like. The piezoelectric vibration element has a configuration in which a metal film that constitutes an excitation electrode, a lead terminal, and the like is formed on a piezoelectric substrate having a vibration part having a thickness suitable for obtaining a target resonance frequency by vapor deposition or the like.
A surface mount type piezoelectric vibrator is provided with an element mounting pad in a recessed portion of a package made of an insulating material such as ceramic, and one end portion of the piezoelectric vibration element by a thermosetting conductive adhesive applied on the element mounting pad. Is supported in a cantilever state, and then the recessed portion is hermetically sealed with a metal lid (lid).
The mounting of the piezoelectric vibration element on the element mounting pad is generally performed by an automatic mounter. The automounter is applied on the element mounting pad provided on the inner bottom surface of the recessed part of the package while adsorbing one side of the piezoelectric vibration element by negative pressure supplied from a plurality of air holes provided on the adsorption surface of the adsorption nozzle The negative pressure supply is stopped with the lower surface of one end of the piezoelectric vibration element approaching the position directly above the conductive adhesive, and the supply of positive pressure from each vent is started to drop the piezoelectric vibration element from the suction surface. . The piezoelectric vibration element is bonded by dropping from a close distance and seating on the conductive adhesive in a state where the lower surface of one end thereof is close to the position immediately above the conductive adhesive.

By the way, as the surface mount type piezoelectric vibrator is reduced in size and height, the storage space for the piezoelectric vibration element in the recessed portion of the package decreases, and one end of the piezoelectric vibration element connected and fixed on the element mounting pad The gap between the free end on the opposite side and the metal lid ceiling surface is easily narrowed.
In this way, when the volume of the package is advancing, if the piezoelectric vibration element surface is mounted in a horizontal posture parallel to the ceiling surface of the metal lid, piezoelectric vibration will occur when a drop impact is applied to the finished piezoelectric device. The element vibrates and bends in the thickness direction. At this time, if the free end portion of the piezoelectric vibration element collides with the metal lid, the vibration frequency may change at that moment, causing a shift or damage.
In order to deal with such problems, the posture when mounting the lower surface of one end of the piezoelectric vibration element on the conductive adhesive on the element mounting pad is mounted so that the free end of the piezoelectric vibration element is inclined upward A technique has been proposed in which the relative inclination angle between the nozzle suction surface and the mounting substrate surface (the bottom surface of the recessed portion) is adjusted. By narrowing the gap between the free end of the piezoelectric vibration element and the metal lid, vibration can be suppressed and buffered by bringing the metal lid into contact with the free end immediately after the free end vibration is generated by impact. It becomes possible.

In Patent Document 1, the distance between the piezoelectric vibrating element and the metal lid is defined to be narrow in order to reduce the impact by dropping and reduce the damage, There has been proposed a technique for reducing the impact by damping the contact.
However, since the piezoelectric vibration element is extremely lightweight, it is easily affected by air resistance when dropped, and even if it is dropped from a close distance in the mounting process by the automatic mounter, the process until the bottom surface of one end reaches the conductive adhesive surface The falling posture is not constant due to variations in air resistance applied to the entire lower surface of the piezoelectric vibration element. In other words, the orientation of the piezoelectric vibration element after fixing is likely to vary due to slight variations in mounting angle during mounting, the influence of stress during curing of the conductive adhesive, etc., and the free end of the piezoelectric vibration element and the metal lid It was extremely difficult to ensure a constant gap between the lower surface.
In addition, when it is necessary to conduct a conductive connection between the pad provided in the package recess and the lead terminal provided on the upper surface of the piezoelectric vibration element by a bonding wire, if the distance between the piezoelectric vibration element and the metal lid is too small It becomes impossible to wire the bonding wire.

In Patent Document 2, a piezoelectric vibration element is arranged by arranging a vibration control body as a buffer material on the free end of the piezoelectric vibration element in order to prevent the free end of the piezoelectric vibration element from colliding with the metal lid due to an impact. A technique for preventing a metal lid from directly colliding is disclosed. According to this, the bonding wire can be wired using the space between the metal lid formed by the vibration control body.
However, when the vibration control body is fixed on the piezoelectric vibration element, problems such as an increase in CI value and disturbance of temperature characteristics are likely to occur in the vibration of the piezoelectric vibration element. In addition, depending on the resin material used as the vibration control body, the aging characteristics may be adversely affected by the generation of outgas. Furthermore, when a resin material is applied to the upper surface of the piezoelectric vibration element that is difficult to keep the distance from the metal lid constant, it becomes more difficult to adjust the gap between the vibration control body and the metal lid, making it difficult to manufacture. Become.

Patent Document 3 discloses a technique for mitigating the impact at the time of dropping by indenting a part of the metal lid toward the concave portion of the package to shorten the distance from the piezoelectric vibration element. Yes.
According to this, it becomes possible to wire a bonding wire using the space between the piezoelectric vibration element formed in the non-dented portion of the metal lid.
However, this complicates the structure of the metal lid, which increases the number of processing steps and increases the cost, and it is necessary to uniquely determine the assembly direction of the metal lid to the package. When assembling the lid, it is necessary to align the direction and front and back of the metal lid, which increases the number of manufacturing steps.

JP 09-186545 A JP 2004-242112 A JP 2007-281572 A

As described above, in order to solve the problem that the piezoelectric vibration element that is cantilevered in the package is greatly shaken in the thickness direction and collides with the metal lid due to an impact at the time of dropping or the like, Although the impact at the time of contact was reduced by narrowing the distance between the element and the metal lid, it was difficult and ineffective to control the distance between the two in a stable manner.
In addition, the method of applying a resin material as a vibration control body on the piezoelectric vibration element may cause deterioration of the characteristics of the piezoelectric device due to the resin material. In addition, the method of reducing the distance between the piezoelectric vibrating element and the metal lid by providing a dent on the metal lid may increase the number of manufacturing steps.
The present invention has been made in view of the above, and on a circuit board including a piezoelectric vibration element in a state where one end of the piezoelectric vibration element is fixed and cantilevered on an element mounting pad provided on a circuit board such as a package. In order to solve the problem of the piezoelectric device having a structure in which the space of the piezoelectric device is enclosed by a lid, the free end of the piezoelectric vibration element vibrates in the thickness direction due to impact and collides with the lid and is damaged. Piezoelectric vibrator capable of preventing the collision with the lid by greatly reducing the amplitude of the free end of the piezoelectric vibration element due to impact without the need for fine adjustment of the gap with the lid when the element is mounted And a piezoelectric oscillator.

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

Application Example 1 This piezoelectric vibrator includes a circuit board having an element mounting pad at the top and a mounting electrode at the bottom, a piezoelectric vibration element having one end fixed on the element mounting pad, and the piezoelectric vibration. A lid that encloses a space on the circuit board including an element, and a wire having both ends fixed to the circuit board so as to straddle at least part of the upper surface of the piezoelectric vibration element; , Provided.

When the piezoelectric vibrator is configured in this manner, in the piezoelectric vibrator having a structure in which a space on the circuit board including the piezoelectric vibration element is surrounded by a lid in a state where one end portion of the piezoelectric vibration element is fixed and cantilevered on the circuit board. When the impact is applied, the problem that the free end portion of the piezoelectric vibration element vibrates in the thickness direction and collides with the lid and is damaged can be solved. The number of wires to be used and the wiring route are arbitrary.

[Application Example 2] In the application example 1, the piezoelectric vibrator has a single-site support structure in which one end of the piezoelectric vibration element is fixed on a single element mounting pad provided on the circuit board. Features.

In a piezoelectric vibrator having a single-site support structure in which one end of a piezoelectric vibration element is fixed, one of the lead terminals on the piezoelectric vibration element needs to be wire-bonded to an element connection pad provided on the circuit board side. However, it is necessary to ensure a sufficiently wide gap between the piezoelectric vibration element and the lid in order to route the wire. In this case, if the free end of the piezoelectric vibration element greatly shakes in the thickness direction due to an impact, there is a possibility that the lid collides with the lid and is damaged. Therefore, it is possible to prevent the piezoelectric vibration element from colliding with the lid by wiring the wire across the upper surface of the piezoelectric vibration element.

[Application Example 3] In this application example 1 or 2, the piezoelectric vibrator is characterized in that the wire is spaced apart from the piezoelectric vibration element at all times.

When there is concern about the deterioration of the characteristics of the piezoelectric vibration element due to the constant contact with the wire, it is preferable that the contact is not made.

Application Example 4 This piezoelectric vibrator is characterized in that, in any one of Application Examples 1 to 3, the wire is wired so as to straddle the upper surface on the free end portion side of the piezoelectric vibration element.

It is preferable that the path and position for wiring the wire are above the upper surface on the free end side of the piezoelectric vibration element. That is, it is possible to effectively prevent the free end from coming into contact with the lid by arranging a wire above the free end that avoids the excitation electrode of the piezoelectric vibration element.

Application Example 5 In this piezoelectric vibrator, in any one of Application Examples 1 to 3, the wire is wired so as to straddle the upper surfaces of the two corners on the free end side of the piezoelectric vibration element. It is characterized by that.

By wiring the wires above the upper surfaces of the two corner portions, the individual wires can be shortened, so that the support strength of the piezoelectric vibration element by the wires when an impact occurs can be increased. The wire breakage rate can also be greatly reduced.

Application Example 6 This piezoelectric oscillator has a circuit board having an element mounting pad and an IC component connection pad on the upper part and a mounting electrode on the lower part, and a piezoelectric vibration having one end fixed on the element mounting pad. A piezoelectric oscillator comprising: an element; an IC component mounted on the circuit board; and a lid surrounding the space on the circuit board including the piezoelectric vibration element and the IC component, wherein the piezoelectric vibration element And a wire fixed to the IC component connecting pad and the IC component at both ends so as to straddle at least a part of the upper surface of the IC component.

In a piezoelectric oscillator in which a piezoelectric vibration element and an IC component are mounted on a circuit board, an electrode on the IC component is wire-bonded to an IC component connection pad on the circuit board, but at least one of these wires is used. Thus, it can be used for damping a piezoelectric vibration element and preventing collision with a lid.

(A) (b) And (b) is the external appearance perspective view of the piezoelectric vibrator which concerns on one Embodiment of this invention, the top view of the state which removed the lid, and a longitudinal cross-sectional view. It is a top view in the state where a lid of a piezoelectric vibrator concerning other embodiments of the present invention was removed. It is a top view in the state where a lid of a piezoelectric vibrator concerning other embodiments of the present invention was removed. (A) And (b) is a principal part top view and longitudinal cross-sectional view which show the structure of the crystal resonator which concerns on other embodiment of this invention. It is a top view in the state where a lid of a piezoelectric vibrator concerning other embodiments of the present invention was removed. It is a top view in the state where a lid of a piezoelectric vibrator concerning other embodiments of the present invention was removed. (A) And (b) is a principal part top view and longitudinal cross-sectional view which show the structure of the piezoelectric oscillator (crystal oscillator) which concerns on one Embodiment of this invention, (c) is a longitudinal cross-sectional view of a modification. . It is a top view which shows the internal structure of the crystal oscillator (piezoelectric oscillator) which concerns on other embodiment of this invention.

Hereinafter, the present invention will be described in detail with reference to embodiments shown in the drawings.
1A, 1B, and 1B are an external perspective view, a plan view, and a longitudinal sectional view of a piezoelectric vibrator according to an embodiment of the present invention, with a lid removed.
A crystal resonator (piezoelectric resonator) 1 includes a package body (circuit board) 2 made of an insulating material such as ceramic and a lid that is fixed to the upper surface of the outer peripheral wall 5 of the package body 2 and hermetically seals the inside of the recessed portion 3. (Metal lid) 15 and a crystal resonator element (piezoelectric resonator element) 20 disposed in a cantilevered manner in the recessed portion 3. The package body 2 includes a ceramic bottom plate 4 and a bottom plate 4.
An annular outer wall (outer peripheral wall) 5 made of ceramic laminated at a required width along the peripheral edge of the upper surface, an annular seal ring (Kovar) 6 fixed along the upper surface of the outer peripheral wall 5, and the recessed portion 3 A single element mounting pad 7 that is exposed and arranged on the inner bottom surface of the quartz crystal and is connected and fixed to one lead terminal of the crystal vibrating element, and is formed on the other part of the inner bottom surface of the recessed portion and crystal vibration through the bonding wire 9 Connection is made between the element connection pad 8 connected to the other lead terminal of the element, the mounting electrode 10 exposed on the outer bottom surface of the bottom plate 4, and the mounting electrode 10, the element mounting pad 7, the element connection pad 8, and the like. And an inner conductor (not shown).

As shown in FIGS. 1B and 1C, the quartz resonator element 20 has a configuration in which excitation electrodes 22 are formed on both main surfaces of the quartz substrate 21, respectively, and when a required alternating current is passed through the excitation electrode 22. The quartz substrate portion (main vibration portion) sandwiched between the front and back excitation electrodes 22 causes a thickness slip and an energy confinement phenomenon, and the main vibration is excited at the excitation electrode attachment portion. The crystal resonator element 20 includes lead terminals 22a and 22b extending from the respective excitation electrodes 22 to the center of one end edge of the substrate.
The lower surface of the substrate end including the lead terminal 22a on the lower surface side is electrically and mechanically connected and fixed by a thermosetting conductive adhesive 25 on the element mounting pad 7. Also, the upper lead terminal 2
2 b is electrically connected to the element connection pad 8 by a bonding wire 9.
The crystal resonator 1 has a single-point support structure in which only the center portion of one end edge of the crystal resonator element 20 is fixed on a single element mounting pad 7 provided on the package body (circuit board) 2. Compared with the conventional type that supports two places on one end edge, the influence of the strain due to the stress from the conductive adhesive on the resonance frequency can be reduced.
Non-connected pads 15 are arranged on the inner bottom surface of the package body 2 and corresponding to both sides in the width direction of the crystal resonator element 20, and both ends of the wire 30 as a buffer member are disposed on each pad 15. It is fixed. The pad 15 may be formed by metallization on a flat surface of the inner bottom surface (ceramic surface) of the package body, or may be formed by metallization on a stepped surface projecting from the inner bottom surface.

The quartz crystal resonator 1 according to the present embodiment has a wire (a loop that forms a loop so as to straddle at least a part of the upper surface of the quartz crystal resonator element 20 and is not in contact with the quartz crystal resonator element at all times.
The structure in which the buffer member 30 is arranged is characteristic. The wire 30 is preferably an elastic or flexible bonding wire made of Al, Au or the like, and wiring is performed by fixing both ends of the wire 30 to each pad 15 by a wire bonding apparatus. When the quartz vibrating element 20 vibrates in the thickness direction due to an impact, the wire 30 is buffered by contact with an appropriate position near the free end (a portion where the excitation electrode 22 is avoided), and the free end is in contact with the bottom surface of the lid. It is a means to prevent. Further, the wire 30 as an elastic body suppresses the vibration by a cushioning action while limiting the swing width of the free end portion of the crystal resonator element upon impact to a short range, and prevents damage due to excessive deformation.
Accordingly, the wire 30 maintains a non-contact state with the crystal resonator element 20 at all times when no impact is applied, but when the crystal resonator element 20 swings in the lid direction due to the impact, the wire 30 is in contact with this to limit the swing width narrowly. In addition, the material, the wire diameter, and the wiring route (wiring shape) may be set so as to absorb and relax the amplitude energy by its elasticity and flexibility. Since the wiring accuracy of the wire by the wire bonding apparatus is high, stable wiring is possible while avoiding contact with the crystal resonator element.
Note that the wire 30 and the lid do not necessarily need to be non-contact, but by keeping the top height of the wire low enough not to contact the lid, the effect of suppressing the swing width of the free end of the crystal resonator element is exhibited. can do.

Further, when the wire 30 is bonded between the pads in a state where the free end of the crystal resonator element is fixed in a state of being tilted upward than usual, it is also expected that the wire contacts the crystal resonator element 20. . When the recessed portion 3 is hermetically sealed with the lid 11 in this contact state, since the characteristic deterioration is detected in the characteristic inspection before product shipment, there is no possibility that a defective product will be shipped.
That is, it is possible to improve the accuracy of detecting a product defect caused by the contact between the wire and the piezoelectric vibration element.
Even if the internal clearance of the package is widely secured, the vibration width of the crystal resonator element when an impact is applied can be limited to a narrow range by the wire, so that the crystal resonator element directly collides with the lid and causes damage. You can eliminate the situation of receiving or cracking.
In addition, instead of performing processing such as adding resin to the quartz resonator element side as in Patent Document 2,
Moreover, since the wire is made of metal, the aging characteristics are not adversely affected by outgas or the like.
Since a flat plate material having no direction can be used as the lid, and the material cost of the wire is small, it is advantageous in terms of cost.
In the embodiment of FIG. 1, an example in which only one wire 30 is used is shown. However, when sufficient strength and vibration control capability cannot be ensured with only one wire 30, two wires as shown in FIG. The above number may be used.

Next, in addition to disposing pads on both sides in the width direction of the bottom surface of the package with the crystal resonator element 20 sandwiched between them as in the embodiment of FIGS. 1 and 2, the crystal resonator element 2 as shown in FIG. Two pads 15 may be arranged so that the wires 30 can be routed across the two free end side corners (corners). That is, in the embodiment of FIG. 3, each wire 30 is wired in a loop shape so as to straddle the upper surface of the corner portion at the free end of the crystal resonator element and in a non-contact state with the crystal resonator element. When the vibrator swings in the thickness direction, the upper surface of each corner (outer edge)
Can be suppressed by each wire 30 to limit the swing width and to suppress vibration. For this reason, it is possible to prevent the occurrence of damage and cracking due to the collision between the crystal resonator element and the lid.
Since the wire 30 wired so as to straddle the upper surface of the corner is shorter than the example of FIGS. 1 and 2, the height of the loop can be easily controlled. The support strength of the crystal resonator element by the wire of the embodiment of FIG. 3 is stronger than the wire of the example of FIG.
If the number of wires used in this way increases, the load applied to each wire decreases, and it is possible to prevent disconnection, deformation, etc. of the wire when the free end portion of the quartz crystal vibration element shakes and contacts.
When a high-accuracy frequency is required, such as a crystal resonator used for GPS, it is necessary to avoid the constant contact between the crystal resonator element and the wire because it causes a significant deterioration in characteristics. . On the other hand, in the case of a crystal resonator as a clock source, the crystal resonator element may be in constant contact with the wire.

Next, FIGS. 4A and 4B are a main part plan view and a longitudinal sectional view showing a configuration of a crystal resonator according to another embodiment of the present invention.
A crystal resonator (piezoelectric resonator) 1 includes a package body (circuit board) 2 made of an insulating material such as ceramic and a lid that is fixed to the upper surface of the outer peripheral wall 5 of the package body 2 and hermetically seals the inside of the recessed portion 3. (Metal lid) 15 and a crystal vibration element (piezoelectric vibration element) 20 disposed in the recessed portion 3
And having. The package body 2 is fixed along a ceramic bottom plate 4, a ceramic annular outer wall (outer peripheral wall) 5 stacked at a required width along the peripheral edge of the upper surface of the bottom plate 4, and an upper surface of the outer peripheral wall 5. An annular seal ring (Kovar) 6, two element mounting pads 7 that are spaced and exposed on the inner bottom surface of the recessed portion 3, and a mounting electrode 10 that is exposed and disposed on the outer bottom surface of the bottom plate 4, And an internal conductor (not shown) for connecting the mounting electrode 10 and the element mounting pad 7 and the like.

As shown in the figure, the quartz resonator element 20 has a configuration in which excitation electrodes 22 are formed on both main surfaces of the quartz substrate 21, and the excitation electrodes 22 on the front and back sides when a required alternating current is passed through the excitation electrode 22.
The quartz crystal substrate portion (main vibration portion) sandwiched between the layers causes a thickness slip and an energy confinement phenomenon, so that the main vibration is excited in the excitation electrode attached portion. The crystal resonator element 20 includes lead terminals 22 a extending from the respective excitation electrodes 22 to one end edge of the substrate, and the lower surface of the substrate end including each lead terminal is formed by a thermosetting conductive adhesive 25 on each element mounting pad 7. Electrically and mechanically connected and fixed. In this example, the lead terminal on the upper surface side of each lead terminal 22a leads the tip to the lower surface side beyond the edge of the substrate, and the end portions of the lead terminals spaced apart on the substrate lower surface are respectively The conductive adhesive 25 on the element mounting pad 7 is connected on a one-to-one basis.
Pads 15 are disposed on the inner bottom surface of the package body and corresponding to both sides in the width direction of the crystal resonator element 20, and both ends of a wire 30 as a buffer member are fixed to each pad 15. The pad 15 may be formed by metallization on a flat surface of the inner bottom surface (ceramic surface) of the package body, or may be formed by metallization on a stepped surface projecting from the inner bottom surface.

In the crystal resonator 1 according to the present embodiment, a wire (buffer member) 30 that forms a loop is disposed so as to straddle at least a part of the upper surface of the crystal resonator element 20 and is not in contact with the crystal resonator element at all times. The configuration is characteristic. As the wire 30, a bonding wire made of Al, Au or the like is preferable, and the wire 30 is formed by a wire bonding apparatus.
Are fixed to each pad 15. The wire 30 is a means for preventing the free end portion from coming into contact with the bottom surface of the lid by buffering the quartz resonator element 20 by contacting with an appropriate position near the free end when the crystal vibrating element 20 vibrates in the thickness direction due to an impact.
Accordingly, the wire 30 maintains a non-contact state with the crystal resonator element 20 and the lid 11 at all times when no impact is applied. On the other hand, when the crystal resonator element 20 swings in the lid direction due to the impact, the wire 30 shakes. The material, the wire diameter, and the wiring path (wiring shape) may be set so that the width is narrowly limited and the amplitude energy is absorbed and relaxed by the elasticity. Since the wiring accuracy of the wire by the wire bonding apparatus is high, stable wiring is possible while avoiding contact with the crystal resonator element.
The effects obtained by providing the wire 30 having flexibility and elasticity are the same as those described in the embodiment of FIG.
In the embodiment of FIG. 4, an example in which only one wire 30 is used has been shown, but two or more wires may be used as shown in FIG.

Next, in addition to disposing pads on both sides in the width direction of the bottom surface of the package with the crystal resonator element 20 interposed therebetween as in the embodiment of FIGS. Two pads 15 may be arranged at each corner so that the wires 30 can be routed across the two corners (corner portions) on the free end side. That is, in the embodiment of FIG. 6, each wire 30 is wired in a loop shape so as to straddle the upper surface of the corner portion at the free end of the crystal resonator element and in a non-contact state with the crystal resonator element. When the vibrator swings in the thickness direction, the upper surface (outer peripheral edge) of each corner is suppressed by each wire 30 to limit the swing width and to control the vibration. For this reason, it is possible to prevent the occurrence of damage and cracking due to the collision between the crystal resonator element and the lid.

Next, FIGS. 7A and 7B are a main part plan view and a longitudinal sectional view showing a configuration of a piezoelectric oscillator (crystal oscillator) according to an embodiment of the present invention, and FIG. It is a longitudinal cross-sectional view. In addition,
The same parts as those of the crystal resonator according to the embodiment of FIG.
The crystal oscillator (piezoelectric oscillator) 50 according to the present embodiment has an element mounting pad 7 and an I
A package body (circuit board) 2 having a C component connection pad 51 and a mounting electrode 10 underneath, a crystal resonator element 20 having one end fixed on the element mounting pad 7, and mounted on the package body. The IC component 60, the lid 11 surrounding the space on the package body 2 including the crystal resonator element 20 and the IC component 60, and the IC component connecting pads at both ends so as to straddle at least part of the upper surface of the crystal resonator element 20. 51 and the wire fixed to the IC component 60 (
Bonding wire) 70.

7A and 7B, the IC component 60 constitutes an oscillation circuit and a temperature compensation circuit, and is mounted on the inner bottom surface of the package body 2 that does not interfere with the crystal resonator element 20. IC component 60
A plurality of electrodes 61 are exposed and disposed on the upper surface of the substrate, and a plurality of IC component connection pads 51 are disposed on the bottom surface of the package body including the side of the crystal resonator element 20. By connecting the IC component connection pads 51a respectively disposed on both sides of the crystal resonator element and the electrode 61a on the IC component by the wire 70a, the wire 70a straddles a part of the upper surface of the crystal resonator element. Wired. The wire 70a is normally spaced above the crystal resonator element so that it is not in contact with the crystal resonator element (especially the excitation electrode 22), but the impact is applied and the free end of the crystal resonator element is in the thickness direction. In the case of swinging, the buffering is performed so as to reduce the amplitude energy while preventing contact with the lid 11 while coming into contact therewith. For this reason, it is possible to prevent the crystal resonator element from being damaged by the collision between the crystal resonator element and the lid.

The wire 70a wired so as to straddle the upper surface of the crystal resonator element is not necessarily a conductive wire, and connects the non-connection IC component connection pad 51 and the non-connection IC component side electrode 61a. A wire may be used for vibration control of the crystal resonator element.
Depending on the application of the crystal oscillator, it may be assumed that the wire 70a is always in contact with the crystal resonator element 20.
In a thin crystal oscillator such as a TCXO, a crystal resonator element and an I
Since the C parts are arranged side by side, it is easy to route the wires along the upper surface of the crystal resonator element.
Next, FIG. 7C is an example in which the IC component 60 is arranged in the low place 4a provided on the inner bottom surface of the package body 2. By arranging the IC component 60 in the low place 4a, the IC component 60 is disposed above the IC component. Since the free end portion of the crystal resonator element is overhanged, and the lateral position of the IC component and the crystal resonator element is partially overlapped, the planar area of the package can be reduced. The configuration in which the wire 70a straddles part of the upper surface of the crystal resonator element is the same as that in the embodiment of FIGS. 7 (a) and 7 (b).

Next, FIG. 8 is a plan view showing an internal configuration of a crystal oscillator (piezoelectric oscillator) according to another embodiment of the present invention. In the embodiment of FIG. 7, the IC component 60 is placed on the inner bottom surface of the package body (circuit board) near the free end of the crystal resonator element 20, but the crystal oscillator 50 according to this embodiment is free of the crystal resonator element 20. The configuration in which the IC component 60 is mounted on the side avoiding the end side is different.
Thus, even when the IC component 60 is arranged on the side of the crystal resonator element 20, the IC component connection pad 51a and the IC can be reduced by devising the position of the IC component connection pad 51a.
It is possible to configure the wiring path of the wire 30 that connects the electrode 61a on the component so as to pass through the upper surface of the crystal resonator element.
In each of the embodiments described above, the package structure in which the plate-shaped lid is fixed on the package body (circuit board) having the recessed portion on the upper surface is exemplified, but the crystal resonator element (and the mounted on the upper surface of the flat circuit board (and The present invention can also be applied to a piezoelectric device (piezoelectric vibrator, piezoelectric oscillator) of a type using an inverted saddle-like lid that encloses a space on a circuit board including IC).

DESCRIPTION OF SYMBOLS 1 ... Crystal oscillator (piezoelectric vibrator), 2 ... Package main body, 3 ... Recessed part, 4 ... Bottom plate, 4a ... Low place, 5 ... Outer peripheral wall, 7 ... Element mounting pad, 8 ... Element connection pad, 9 ... Bonding Wire 10, Mounting electrode 11, Lid, 15 Pad, 20 Crystal oscillator, 21 Crystal substrate (piezoelectric substrate) 22 Excitation electrode, 22 a Lead terminal, 22 b Lead terminal, 25 Conductive bonding Agent, 30 ... wire, 50 ... crystal oscillator (piezoelectric oscillator), 51, 51a ... IC component connection pad, 60 ... IC component, 61, 61a ... IC component side electrode, 70a ... wire

Claims (6)

A circuit board having an element mounting pad at the top and a mounting electrode at the bottom, a piezoelectric vibration element having one end fixed on the element mounting pad, and a space on the circuit board including the piezoelectric vibration element A piezoelectric vibrator comprising:
A piezoelectric vibrator comprising: a wire having both ends fixed to the circuit board so as to straddle at least a part of an upper surface of the piezoelectric vibration element. 2. The piezoelectric vibrator according to claim 1, wherein the piezoelectric vibrator has a single-point support structure in which one end of the piezoelectric vibration element is fixed on a single element mounting pad provided on the circuit board. 3. The piezoelectric vibrator according to claim 1, wherein the wires are spaced apart so as to be in non-contact with the piezoelectric vibration element at all times. 4. The piezoelectric vibrator according to claim 1, wherein the wire is wired so as to straddle a free-end-side upper surface of the piezoelectric vibration element. 5. 4. The piezoelectric vibrator according to claim 1, wherein the wires are wired so as to straddle the upper surfaces of the two corners on the free end side of the piezoelectric vibration element. 5. A circuit board having an element mounting pad and an IC component connection pad on the upper side and a mounting electrode on the lower part, a piezoelectric vibration element having one end fixed on the element mounting pad, and mounted on the circuit board. A piezoelectric oscillator comprising: an IC component; and a lid surrounding a space on the circuit board including the piezoelectric vibration element and the IC component,
A piezoelectric oscillator comprising: a wire for fixing the IC component connection pad and the IC component at both ends so as to straddle at least a part of the upper surface of the piezoelectric vibration element.

Images