JP2016086381A - Piezoelectric device and manufacturing method of piezoelectric device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a piezoelectric oscillator which is suitably packaged.SOLUTION: An oscillator 1 includes: a wiring board 7 including a pad 41 for a vibrator provided on a first main surface 37a and an external terminal 43 provided on a second main surface 37b and connected to the pad 41 for a vibrator; a vibrator 3 mounted on the pad 41 for a vibrator so as to cover an opening 37h of the wiring board 7; an integrated circuit element 5 located within the opening 37h and mounted to the vibrator 3; and a surrounding part 8 comprising an insulation material in close contact with an outer peripheral surface of the vibrator 3 and a peripheral part of the vibrator 3 in the first main surface 37a.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a piezoelectric device such as a crystal oscillator and a method for manufacturing the piezoelectric device.

  As a crystal oscillator having a crystal resonator element and an oscillation circuit (integrated circuit element) that generates an oscillation signal by applying a voltage to the crystal resonator element, for example, a first recess in which the crystal resonator element is accommodated in a first main surface Is formed, and has a so-called H-type package in which a second concave portion for accommodating an integrated circuit element is formed on a second main surface on the back surface thereof (for example, Patent Document 1). In this crystal oscillator, for example, the second main surface is opposed to the circuit board, and the pad formed around the second concave portion of the second main surface and the pad of the circuit board are joined by the bump, Mounted on a circuit board.

  A crystal resonator that includes a crystal resonator element and a package that accommodates the crystal resonator element and does not include an oscillation circuit (integrated circuit element) is also well known. There is also known a crystal oscillator configured by mounting such a crystal resonator and an integrated circuit element having an oscillation circuit on the same wiring board having external terminals and sealing with resin (for example, Patent Document 2). 3)

JP 2000-49560 A Japanese Patent Application Laid-Open No. 2005-244639 JP 2006-340035 A

  The crystal oscillator having the H-type package described above is reduced in size because, for example, the package is integrated as a whole as compared with a configuration in which a crystal resonator is mounted on a wiring board on which an integrated circuit element is mounted. Etc. are advantageous. On the other hand, for example, when changing the joint (pad or the like) between the crystal oscillator and the circuit board on which the crystal oscillator is mounted, there arises a disadvantage that the design of the entire package needs to be changed. The techniques disclosed in Patent Documents 2 and 3 are disadvantageous for miniaturization because the crystal resonator and the integrated circuit element are mounted in parallel, resulting in a large wiring board.

  Accordingly, it is desirable to provide a suitably packaged piezoelectric device and method for manufacturing the same.

  A piezoelectric device according to an aspect of the present invention includes a vibrator pad provided on one main surface, an external terminal provided on the other main surface and connected to the vibrator pad, and penetrating in a thickness direction. A wiring substrate having an opening to be covered; a piezoelectric vibrator mounted on the vibrator pad so as to cover the opening; an electronic element located in the opening and mounted on the piezoelectric vibrator; An outer peripheral surface of the piezoelectric vibrator, and an enclosing portion made of an insulating material that is in close contact with a peripheral portion of the one main surface of the piezoelectric vibrator.

  Preferably, the surface of the piezoelectric vibrator opposite to the wiring board is exposed from the surrounding portion.

  Preferably, the surface of the piezoelectric vibrator opposite to the wiring substrate and the surface of the surrounding portion opposite to the wiring substrate are flush with each other.

  Preferably, the wiring board is provided outside the piezoelectric vibrator in a plan view, the through-hole penetrating the wiring board in the thickness direction, the through-hole, and the vibrator pad and the external terminal And the surrounding portion covers the through hole.

  The method for manufacturing a piezoelectric device according to one aspect of the present invention includes a vibrator pad provided on one main surface, an external terminal provided on the other main surface and connected to the vibrator pad, and a thickness. A piezoelectric substrate mounted on the one main surface so as to cover the opening on a mother board on which a large number of wiring boards having openings that penetrate in the direction are taken; A step of providing an electronic element mounted on a vibrator; and in the mother substrate provided with the piezoelectric vibrator, supplying a solid insulating material to the one main surface to solidify the one main surface Forming an insulating layer in close contact with a peripheral portion of the piezoelectric vibrator and an outer peripheral surface of the piezoelectric vibrator, and cutting the mother substrate and the insulating layer with a blade from the other main surface side. Step to divide It has.

  Preferably, in the step of forming the insulating layer, the surface of the piezoelectric vibrator opposite to the wiring substrate and the surface of the insulating layer opposite to the wiring substrate are flush with each other. The insulating layer is formed.

  According to said structure, the packaged piezoelectric device is implement | achieved suitably.

1 is an exploded perspective view showing a schematic configuration of a crystal oscillator according to a first embodiment of the present invention. Sectional drawing in the II-II line of FIG. 3A and 3B are plan views of the front and back of the substrate portion of the crystal oscillator of FIG. 4 (a) to 4 (d) are plan views for explaining a method of manufacturing the crystal oscillator of FIG. The disassembled perspective view which shows schematic structure of the crystal oscillator which concerns on 2nd Embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the drawings used in the following description are schematic, and the dimensional ratios and the like on the drawings do not necessarily match the actual ones.

  Further, for the purpose of clarifying the relationship between the drawings, the rectangular coordinate system xyz may be attached to the drawings for the sake of convenience. The x-axis, y-axis, and z-axis are defined for convenience based on the shape of the member and the like, and do not mean the electric axis, mechanical axis, and optical axis of the piezoelectric body (quartz).

<First Embodiment>
(Configuration of crystal oscillator)
FIG. 1 is an exploded perspective view showing a schematic configuration of a crystal oscillator 1 (hereinafter, “crystal” is omitted) according to an embodiment of the present invention. 2 is a cross-sectional view taken along line II-II in FIG.

  The oscillator 1 is, for example, an electronic component that is generally thin and has a thin rectangular parallelepiped shape as a whole, and the dimensions thereof may be set as appropriate. For example, in a comparatively small thing, the length of a long side or a short side is 1-2 mm, and thickness is 0.2-0.4 mm.

  The oscillator 1 includes, for example, a crystal resonator 3 (hereinafter, “crystal” is omitted), an integrated circuit element 5 mounted on the resonator 3, a wiring board 7 on which the resonator 3 is mounted, and the resonator 3. It has the surrounding part 8 for sealing the circumference | surroundings. The surrounding portion 8 is not a part to be assembled and is a member that cannot be removed without breaking, but is also shown in FIG. 1 for convenience.

  When an alternating voltage is applied, the vibrator 3 generates a natural vibration therein. The integrated circuit element 5 includes an oscillation circuit, applies a voltage to the vibrator 3, and generates an oscillation signal using the natural vibration in the vibrator 3. The wiring board 7 is connected to a circuit board (not shown) or the like, and mediates an electrical signal between the circuit board and the integrated circuit element 5 through the package of the vibrator 3. These specific configurations are, for example, as follows.

  The vibrator 3 includes, for example, a crystal vibration element 9 (hereinafter, “crystal” is omitted), an element mounting member 11 that houses the vibration element 9, and a lid member 13 that seals the element mounting member 11. . The element mounting member 11 and the lid member 13 constitute a package of the vibrator 3.

  The vibration element 9 includes, for example, a crystal piece 15, a pair of excitation electrodes 17 for applying a voltage to the crystal piece 15, and a pair of extraction electrodes 19 for mounting the vibration element 9 on the element mounting member 11. have.

  The crystal piece 15 is formed in a substantially rectangular plate shape, for example. The crystal piece 15 is made of, for example, an AT cut crystal piece. The pair of excitation electrodes 17 is provided in a layered manner on the center side of both main surfaces of the crystal piece 15, for example. For example, the pair of extraction electrodes 19 are extracted from the pair of excitation electrodes 17 and provided at one end side portion in the longitudinal direction of the crystal piece 15. The pair of excitation electrodes 17 and the pair of extraction electrodes 19 are, for example, center lines (not shown) extending in the longitudinal direction of the crystal piece 15 so that either of the main surfaces of the vibration element 9 may be the mounting side. Is formed in a 180 ° rotationally symmetric shape.

  The element mounting member 11 includes, for example, an insulating base 21 and various conductors (for example, metal) provided on the base 21. The various conductors include, for example, a pair of element mounting pads 23 for mounting the vibration element 9 on the element mounting member 11 and a plurality of (four in this embodiment) for mounting the vibrator 3 on the wiring board 7. The vibrator terminals 25 and a plurality (six in this embodiment) of IC pads 26 (FIG. 2) for mounting the integrated circuit element 5 on the vibrator 3.

  The base 21 is made of, for example, ceramic and has a concave portion 21r that accommodates the vibration element 9. The base 21 includes, for example, a flat plate-like substrate portion 21a and a frame portion 21b overlapped with the substrate portion 21a, thereby forming a recess 21r.

  For example, the pair of element mounting pads 23 are provided in a layered manner on the bottom surface of the recess 21r (the main surface of the substrate portion 21a on the frame portion 21b side). The plurality of transducer terminals 25 are provided in a layered manner at, for example, the four corners of the main surface of the substrate portion 21a opposite to the frame portion 21b (see FIG. 3B). The plurality of IC pads 26 are arranged in, for example, two rows in a region surrounded by the plurality of transducer terminals 25 on the main surface of the substrate portion 21a opposite to the frame portion 21b (FIG. 3 ( b)).

  The vibration element 9 is fixed to the element mounting member 11 like a cantilever by joining a pair of extraction electrodes 19 and a pair of element mounting pads 23 by a pair of bumps 27 (FIG. 2). And electrically connected to the element mounting member 11. The bump 27 is made of, for example, a conductive adhesive.

  The lid member 13 is made of metal, for example. The lid member 13 is joined to the frame portion 21b of the element mounting member 11, whereby the concave portion 21r is sealed. The inside of the recess 21r is, for example, a vacuum or an appropriate gas (for example, nitrogen) is sealed.

  The lid member 13 and the element mounting member 11 may be joined by an appropriate method. For example, a frame-shaped first bonding pattern 29 made of metal is formed on the surface of the frame portion 21b on the lid member 13 side. On the other hand, a frame-shaped second bonding pattern 31 made of metal is formed on the surface of the lid member 13 on the frame portion 21b side. And the cover member 13 and the element mounting member 11 are mutually joined by joining both by seam welding.

  The integrated circuit element 5 is formed in, for example, a substantially thin rectangular parallelepiped shape, and has a plurality (six in this embodiment) of IC terminals 33 on one main surface. The integrated circuit element 5 is fixed to the element mounting member 11 by bonding the IC terminal 33 and the aforementioned IC pad 26 provided on the element mounting member 11 by the bump 35 (FIG. 2). The element mounting member 11 is electrically connected.

  The number and role of the IC terminals 33 may be set as appropriate according to functions required for the oscillator 1. For example, one of the six IC terminals 33 is for supplying a reference potential to the integrated circuit element 5, and one supplies a power supply voltage (potential different from the reference potential) to the integrated circuit element 5. 2 for applying a voltage from the integrated circuit element 5 to the vibration element 9, and 1 for outputting an oscillation signal generated by the integrated circuit element 5. One is to input a control signal for adjusting the frequency of the oscillation signal to the integrated circuit element 5 or an enable / disable signal that instructs the integrated circuit element 5 to generate or stop the oscillation signal. This is for inputting to the element 5.

  As already described, the integrated circuit element 5 includes an oscillation circuit. The oscillation circuit is, for example, a feedback type. The integrated circuit element 5 may include a temperature sensor and a temperature compensation circuit that compensates for a temperature change of the oscillation signal based on the temperature detected by the temperature sensor. The integrated circuit element 5 may be packaged or a bare chip.

  For example, the wiring board 7 may have the same configuration as a rigid printed wiring board. For example, the wiring substrate 7 includes an insulating substrate 37, various conductors (for example, metal) provided on the insulating substrate 37, and a solder resist 39 that appropriately covers the insulating substrate 37. The various conductors include, for example, a plurality (four in this embodiment) of vibrator pads 41 for mounting the vibrator 3 on the wiring board 7 and a plurality of parts for mounting the wiring board 7 on a circuit board (not shown). These are four (in this embodiment) external terminals 43 and a plurality (four in this embodiment) of connecting conductors 45 that connect the plurality of transducer pads 41 and the plurality of external terminals 43.

  The insulating substrate 37 is made of, for example, a glass epoxy material. The insulating substrate 37 (wiring substrate 7) has an opening that penetrates the first main surface 37a, the second main surface 37b on the back surface, and the thickness direction (z direction; from the first main surface 37a to the second main surface 37b). 37h and a plurality of (four in this embodiment) through-holes 37e penetrating in the thickness direction around the opening 37h. Hereinafter, the main surface of the wiring board 7 may be referred to by reference numerals 37a and 37b.

  The planar shape of the outer edge of the insulating substrate 37, the opening 37h and the through hole 37e may be set as appropriate. For example, the planar shape of the outer edge of the insulating substrate 37 is a rectangle. The planar shape of the opening 37h is, for example, a rectangular shape (including one with chamfered corners; an example in FIG. 1), an oval shape, an elliptical shape, or a circular shape in which a rectangular short side is an arc shape. The planar shape of the through hole 37e is, for example, a circle. The through hole 37e is preferably separated from the side surface of the insulating substrate 37 inward.

  The plurality of vibrator pads 41 are provided in a layered manner on the four corners of the first main surface 37a, for example, and surround the opening 37h. The plurality of external terminals 43 are, for example, provided in layers at the four corners of the second main surface 37b and surround the opening 37h. The plurality of connection conductors 45 are provided in layers on the inner peripheral surfaces of the plurality of through holes 37e, for example. The plurality of connection conductors 45 (the plurality of through holes 37e) are provided, for example, on the four corners of the main surface of the insulating substrate 37 and surround the opening 37h.

  For example, the solder resist 39 is provided over the entire first main surface 37a so as to surround the vibrator pad 41 and the connection conductor 45 on the first main surface 37a. Thereby, the possibility that the vibrator pads 41 are short-circuited by the bumps 47 (FIG. 2) arranged on the vibrator pad 41 is reduced.

  The plurality of through holes 37e are located on the opposite side of the opening 37h with respect to the vibrator pad 41, for example. The connection conductor 45 has, for example, a flange portion around the through hole 37e of the first main surface 37a, and the flange portion is directly connected to the vibrator pad 41 without a wiring. The through hole 37e does not overlap with the vibrator pad 41 or overlaps with the vibrator pad 41 in a relatively small amount. Further, the plurality of through holes 37 e are provided at positions overlapping the external terminals 43, for example. For example, a portion of the connection conductor 45 provided on the inner peripheral surface of the through hole 37 e is directly connected to the external terminal 43.

  The vibrator 3 is bonded to the wiring substrate 7 by bonding the plurality of vibrator terminals 25 provided on the element mounting member 11 and the vibrator pad 41 with bumps 47 (FIG. 2). It is fixed and electrically connected. Since the vibrator pad 41 is disposed so as to surround the opening 37h, the vibrator 3 is mounted on the wiring board 7 so as to cover the opening 37h from the first main surface 37a side. The area of the vibrator 3 is larger than the area of the opening 37h, for example, and the opening 37h fits in the vibrator 3 in plan view.

  Further, the integrated circuit element 5 mounted on the vibrator 3 is accommodated in the opening 37h. In FIG. 2, the top surface of the integrated circuit element 5 (z-direction negative surface) is located on the inner side (z-direction positive side) than the second main surface 37 b. It may be substantially flush with the second main surface 37b.

  In plan view, the wiring board 7 is larger than the vibrator 3. Then, in the first main surface 37a, the insulating material in a molten state is supplied around the vibrator 3, and the insulating material is then solidified, whereby the surrounding portion 8 is formed. Accordingly, the surrounding portion 8 is in close contact with the first main surface 37 a (strictly speaking, the solder resist 39 in the present embodiment) and the side surface of the vibrator 3.

The material of the surrounding portion 8 may be appropriately selected. For example, the surrounding portion 8 is made of a resin or a resin containing an appropriate filler. The resin is, for example, a thermosetting resin (for example, an epoxy resin). The filler is made of, for example, an inorganic material (for example, SiO ₂ ) having a lower coefficient of thermal expansion than the resin. Moreover, the surrounding part 8 may be comprised with the inorganic material of the amorphous state.

  The top surface (surface opposite to the wiring substrate 7) of the vibrator 3 is exposed from, for example, the top surface (surface opposite to the wiring substrate 7) of the surrounding portion 8, and these top surfaces are also exposed. They are flush with each other. Further, the side surface of the surrounding portion 8 and the side surface of the wiring substrate 7 are flush with each other, for example. For example, at least a part of the connection conductor 45 and the through hole 37e are located outside the vibrator 3 in plan view, and the surrounding portion 8 covers the connection conductor 45 and the through hole 37e. In addition, the surrounding part 8 may be filled in the through-hole 37e, and does not need to be filled.

An underfill 49 (FIG. 2) is filled between the integrated circuit element 5 and the vibrator 3. The underfill 49 is made of, for example, a thermosetting resin (for example, an epoxy resin). The underfill 49 may include a filler (for example, made of SiO ₂ ) having a lower thermal expansion coefficient than that of the resin. The underfill 49 may be provided so as to cover the side surface of the integrated circuit element 5 to an appropriate height, or may be provided so as to cover not only the side surface but also the top surface of the integrated circuit element 5.

  The base 21 of the element mounting member 11 (vibrator 3) faces the insulating substrate 37 of the wiring substrate 7 with a gap corresponding to the thickness of the transducer terminal 25, the bump 47, and the transducer pad 41. The outside of this gap is closed by the surrounding portion 8. The surrounding portion 8 or the underfill 49 may or may not extend to the gap between the base 21 and the insulating substrate 37.

  In the element mounting member 11, two of the six IC pads 26 and a pair of element mounting pads 23 are connected. Thus, the integrated circuit element 5 mounted on the IC pad 26 and the vibration element 9 mounted on the element mounting pad 23 are electrically connected. As a result, the integrated circuit element 5 can apply a voltage to the vibration element 9 to generate an oscillation signal.

  In the element mounting member 11, the remaining four of the six IC pads 26 and the four transducer terminals 25 are connected. Thereby, the integrated circuit element 5 mounted on the IC pad 26 and the wiring board 7 having the vibrator pad 41 to which the vibrator terminal 25 is bonded are electrically connected. As a result, it is possible to input / output electric signals to / from the integrated circuit element 5 by inputting / outputting electric signals to / from the four external terminals 43 of the wiring board 7 connected to the vibrator pads 41 via the connection conductors 45. It has become.

  FIG. 3A and FIG. 3B are diagrams for explaining an example of connection in the element mounting member 11 as described above. Specifically, FIG. 3A is a plan view of the substrate portion 21a viewed from the vibration element 9, and FIG. 3B is a plan view of the substrate portion 21a viewed from the integrated circuit element 5 side. .

  As shown in FIG. 3A, a pair of first connection patterns 51 extend from a pair of element mounting pads 23 and are connected to a pair of first via conductors 53. As shown in FIG. 3B, the pair of first via conductors 53 penetrates the substrate portion 21 a in the thickness direction and is connected to the pair of second connection patterns 55. The pair of second connection patterns 55 are connected to the two IC pads 26. Further, as shown in FIG. 3B, the remaining four IC pads 26 are connected to the four transducer terminals 25 via the four third connection patterns 57.

  The first connection pattern 51, the second connection pattern 55, and the third connection pattern 57 are formed in layers. The first connection pattern 51 may partially overlap the frame portion 21b. The reason why the middle of the pair of second connection patterns 55 is wide is to make a probe of an inspection apparatus that inspects characteristics of the vibration element 9 abut in the manufacturing process of the oscillator 1. The second via conductor 59 is for connecting the vibrator terminal 25 to which the reference potential is applied and the lid member 13 made of a conductor, and the frame portion 21b also penetrates in the thickness direction.

(Manufacturing method of crystal oscillator)
4A to 4D are schematic views for explaining a method for manufacturing the oscillator 1.

  First, as shown in FIG. 4A, a mother board 101 on which a large number of wiring boards 7 are taken is prepared. In FIG. 4A, illustrations other than the opening 37h are omitted, but at this point, for example, the wiring board 7 is substantially formed. That is, at this time, the opening 37h, the through hole 37e, the solder resist 39, the vibrator pad 41, the external terminal 43, and the connection conductor 45 are provided. The formation method of the mother substrate 101 may be the same as a known method except for a specific shape and the like. The opening 37h may be formed by punching, cutting, or etching, for example. Moreover, the through-hole 37e may be formed by cutting with a drill etc., for example.

  Next, as shown in FIG. 4B, the vibrator 3 and the integrated circuit element 5 are provided on the mother substrate 101. That is, the bonding of the vibration element 9 to the element mounting member 11, the bonding of the lid member 13 to the element mounting member 11, the bonding of the integrated circuit element 5 to the element mounting member 11, and the wiring substrate 7 (mother substrate 101) of the element mounting member 11. ).

  As long as the joining of the lid member 13 to the element mounting member 11 is after the joining of the vibration element 9 to the element mounting member 11, any joining order is possible. Further, the characteristics of the vibration element 9 are inspected through a measurement pad (in this embodiment, the integrated circuit element 5 overlaps) formed by expanding a part of the second connection pattern 55, and the excitation electrode 17 of the excitation electrode 17 is responded accordingly. When adjusting the weight, the bonding of the integrated circuit element 5 to the element mounting member 11 is after the bonding of the vibration element 9 to the element mounting member 11.

  Next, as illustrated in FIG. 4C, the insulating layer 103 to be the surrounding portion 8 is formed. Specifically, for example, a molten insulating material is supplied, and then the insulating material is solidified by heating or drying. The supply method and the solidification method may be the same as known methods. For example, the thermosetting resin may be cured by supplying the thermosetting resin by screen printing and then passing through a reflow furnace or the like.

  The surface of the insulating layer 103 opposite to the mother substrate 101 is flush with the surface of the vibrator 3 opposite to the mother substrate 101. The flushing method may be realized by appropriately adjusting the supply amount of the insulating material in the molten state, or may be realized by performing polishing or the like after supplying a relatively large amount of the insulating material. Good.

  Next, as shown in FIG. 4D, the mother substrate 101 and the insulating layer 103 are cut into pieces. Thereby, the wiring board 7 and the surrounding part 8 are comprised, and by extension, the oscillator 1 is comprised. The cutting is performed by, for example, a dicing blade 109 that rotates about a rotation axis (not shown) parallel to the left-right direction in FIG. More specifically, for example, the surface of the insulating layer 103 and the vibrator 3 opposite to the mother substrate 101 is attached to the table 107 with the dicing tape 105 and cut from the second main surface 37b side.

  As described above, in the present embodiment, the oscillator 1 includes the vibrator pad 41 provided on the first main surface 37a and the external terminal provided on the second main surface 37b and connected to the vibrator pad 41. The wiring board 7 having the wiring 43, the vibrator 3 mounted on the vibrator pad 41 so as to cover the opening 37 h of the wiring board 7, and the integrated circuit mounted on the vibrator 3 that is located in the opening 37 h. The element 5 and the surrounding part 8 which consists of an insulating material closely_contact | adhered to the peripheral part of the vibrator | oscillator 3 among the outer peripheral surfaces of the vibrator | oscillator 3, and the 1st main surface 37a are included.

  Therefore, for example, the package of the oscillator 1 can be configured by a combination of the package of the vibrator 3 (the element mounting member 11 and the lid member 13), the wiring substrate 7, and the surrounding portion 8. As a result, for example, the arrangement and size of the external terminals 43 can be easily changed by changing or replacing the wiring board 7. Further, for example, the integrated circuit element 5 is accommodated in the opening 37h as compared with the case where both the vibrator and the integrated circuit element are mounted on the wiring board to constitute the oscillator, and thus the size can be reduced.

  Furthermore, since the surrounding portion 8 is in close contact with (covers) the vibrator 3 and the wiring board 7 around the vibrator 3, for example, the rigidity of the oscillator 1 can be increased. As a result, for example, when a stress is applied to the oscillator 1 from the outside, the stress applied to the joint portion between the wiring board 7 and the vibrator 3 can be reduced. As a result, the possibility that the output signal changes due to the change in the bonding state between the wiring board 7 and the vibrator 3 can be reduced. That is, the oscillation signal is stabilized. In addition, since the joint portion between the wiring board 7 and the vibrator 3 is covered with the surrounding portion 8 and is not exposed, adhesion of dust and other foreign matters to the joint portion is reduced. The output signal from becomes stable. The integrated circuit element 5 is accommodated in the opening 37 h, and the second main surface 37 b side where the external terminal 43 is provided is not covered by the surrounding portion 8. That is, the integrated circuit element 5 is not covered by the surrounding portion 8. Therefore, for example, the heat of the integrated circuit element 5 is dissipated to the second main surface 37b side without entering the surrounding portion 8. As a result, for example, it is expected that the heat of the integrated circuit element 5 is suppressed from affecting the frequency characteristics of the vibrator 3.

  In the present embodiment, the surface of the vibrator 3 opposite to the wiring board 7 is exposed from the surrounding portion 8.

  Therefore, a part of the vibrator 3 (the lid member 13) can be used as it is as a part of the package of the oscillator 1 to reduce the thickness. Further, while the surrounding portion 8 improves the strength around the vibrator 3, the heat in the vibrator 3 is released from the lid member 13 or the ground is connected to the lid member 13 to stabilize the potential. Can do. The vibrator 3 is easy to dissipate heat or heat because the cover member 13 is exposed and the opposite side faces the opening 37h. On the other hand, the surrounding part 8 can absorb heat from surrounding electronic components. Not easily affected. Therefore, temperature control is easy.

  In the present embodiment, the surface of the vibrator 3 opposite to the wiring substrate 7 and the surface of the surrounding portion 8 opposite to the wiring substrate 7 are flush with each other.

  Therefore, while obtaining the maximum strength improvement effect by the surrounding portion 8, the above-described effects of the thinning, the heat radiation from the lid member 13, the stabilization of the potential of the lid member 13 due to the exposure of the lid member 13 are obtained. Can be obtained. Moreover, since the surrounding part 8 will contact | adhere to the outer peripheral surface of the cover member 13 and the outer peripheral surface of the element mounting member 11, these joint strengths also improve. As in the present embodiment, when the lid member 13 is positioned inside the outer edge of the frame portion 21b of the element mounting member 11, the surrounding portion 8 engages with the frame portion 21b toward the wiring board 7 side. The bonding state between the vibrator 3 and the wiring board 7 is more preferably improved.

  Further, in the present embodiment, the wiring board 7 is provided outside the vibrator 3 in a plan view, the through-hole 37e penetrating the wiring board 7 in the thickness direction, and the through-hole 37e. And a connection conductor 45 for connecting to the external terminal 43. And the surrounding part 8 has covered the through-hole 37e.

  Therefore, for example, the connection conductor 45 is provided on the outer peripheral portion of the wiring board 7 which is a precondition for providing the surrounding portion 8 (the portion located outside the vibrator 3). There is no need to secure a dedicated space, and the size can be reduced. Further, for example, when the connection conductor 45 is covered by the surrounding portion 8, dust and dirt are prevented from adhering to the connection conductor 45, and the signal output from the oscillator 1 is stabilized.

  In the present embodiment, since the connecting conductor 45 overlaps the surrounding portion 8, the insulating material constituting the surrounding portion 8 enters the through hole 37 e, and as a result, the surrounding portion 8 is formed on the surface of the connecting conductor 45. Thus, the connection strength between the connection conductor 45 and the through hole 37e can be increased. If the crystal oscillator according to the present embodiment is mounted on a mounting substrate such as an electronic device, even if stress is applied to the wiring substrate 7 and the wiring substrate 7 is warped, the insulating material that constitutes the surrounding portion 8 Thus, since the connection strength between the connection conductor 45 and the through hole 37e is increased, it is possible to prevent the connection conductor 45 from being peeled off from the inner surface of the through hole 37e. Therefore, in this embodiment, poor conduction between the vibrator pad 41 and the external terminal 43 can be reduced.

  In addition, the manufacturing method of the oscillator 1 according to the present embodiment includes a vibrator pad 41 provided on the first main surface 37a, an external terminal 43 provided on the second main surface 37b and connected to the vibrator pad 41, In addition, the vibrator 3 mounted on the first main surface 37a so as to cover the openings 37h on the mother board 101 on which a large number of wiring boards 7 having openings 37h penetrating in the thickness direction are taken, and the openings 37h. In the step of providing the integrated circuit element 5 mounted on the vibrator 3 (FIG. 4B) and the mother substrate 101 provided with the vibrator 3, the first main surface 37a is in a molten state. Supplying and solidifying an insulating material to form an insulating layer 103 in close contact with the peripheral portion of the vibrator 3 and the outer peripheral surface of the vibrator 3 in the first main surface 37a (FIG. 4C); The mother substrate 101 and the insulating layer 103 on the second main surface 37b side And a step (FIG. 4 (d)) into individual pieces by cutting with a dicing blade 109.

  Here, unlike the present embodiment, when the insulating layer 103 is not provided, the surface of the vibrator 3 opposite to the wiring substrate 7 is supported by the table 107, and the dicing blade 109 from the second main surface 37b side. When the mother board 101 is cut, the wiring board 7 is bent. For this reason, when the insulating layer 103 is not provided, the mother substrate 101 must be cut from the first main surface 37a side. When the mother substrate 101 is cut from the first main surface 37a side by the dicing blade 109, there is a possibility that a burr protruding to the second main surface 37b side is generated at the time of cutting. Since this burr protrudes to the outside of the oscillator, for example, when the oscillator 1 is arranged in a socket for inspection, it causes a contact failure, which leads to a decrease in productivity.

  However, in this embodiment, since the insulating layer 103 (enclosure 8) is provided, the side opposite to the wiring substrate 7 of the vibrator 3 is supported by the table 107 and cut from the second main surface 37b side. However, the bending of the wiring board 7 is suppressed. That is, cutting in such a direction can be realized. As a result, the occurrence of burrs protruding toward the second main surface 37b is also suppressed, and the productivity is improved.

  In the present embodiment, in the step of forming the insulating layer 103, the surface of the vibrator 3 opposite to the wiring substrate 7 and the surface of the insulating layer 103 opposite to the wiring substrate 7 are flush with each other. Thus, the insulating layer 103 is formed. Therefore, the effect of suppressing the bending of the wiring board 7 during the above-described cutting is more remarkably exhibited.

Second Embodiment
FIG. 5 is an exploded perspective view corresponding to FIG. 1 and showing the oscillator 201 according to the second embodiment. The configuration of the oscillator according to the second embodiment is the same as the configuration of the oscillator 1 according to the first embodiment except for the configuration of the wiring board 207. Also, the wiring board 207 according to the second embodiment is the same as the wiring board 7 of the first embodiment, unless otherwise specified.

  Similar to the wiring substrate 7 of the first embodiment, the wiring substrate 207 according to the second embodiment is provided on the insulating substrate 237 having the opening 237h and the plurality of through holes 237e, and the first main surface 237a of the insulating substrate 237. The vibrator pad 241 on which the vibrator 3 is mounted, the second main surface 237b of the insulating substrate 237, the external terminal 243 connected to a circuit board (not shown), and the through hole 237e, A connection conductor 245 that connects the vibrator pad 241 and the external terminal 243 is provided.

  However, the wiring board 207 is different from the wiring board 7 of the first embodiment in the following points, for example. First, the through-hole 237e is located on the opening 237h side with respect to the vibrator pad 241 in a plan view, and is connected to the opening 237h. Further, the through hole 237e overlaps with the vibrator pad 241 and the connection conductor 245 is directly connected to the vibrator pad 241 at a portion formed on the inner peripheral surface of the through hole 237e.

  Also in the second embodiment described above, the same effects as in the first embodiment are achieved. For example, since the package of the oscillator 201 is configured by the combination of the package of the vibrator 3 (the element mounting member 11 and the lid member 13), the wiring board 207, and the surrounding portion 8, the package is small. Easy design change. By the surrounding portion 8, the bonding state between the vibrator 3 and the wiring board 207 is stabilized, and as a result, the signal output from the oscillator 201 is stabilized.

  In the second embodiment, since the connecting conductor 245 overlaps the surrounding portion 8, the insulating material constituting the surrounding portion 8 enters the through hole 237e. As a result, the surrounding portion is formed on the surface of the connecting conductor 245. 8 can be provided, and the connection strength between the connection conductor 245 and the through hole 237e can be increased. Temporarily, when the crystal oscillator of the second embodiment is mounted on a mounting substrate such as an electronic device, even if stress is applied to the wiring substrate 207 and the wiring substrate 207 is warped, the insulating material that constitutes the surrounding portion 8 Thus, since the connection strength of the connection conductor 245 with the through hole 237e is increased, the connection conductor 245 can be prevented from being peeled off from the inner surface of the through hole 237e. Therefore, in the second embodiment, poor conduction between the vibrator pad 241 and the external terminal 243 can be reduced.

  In the second embodiment, since the thermosetting resin constituting the underfill 49 and the insulating member constituting the surrounding portion 8 are joined via the vibrator 3 and the wiring board 207, the integration is performed. The bonding strength between the circuit element 5 and the vibrator 3 can be improved.

  In the above embodiment, the crystal oscillator 1 is an example of a piezoelectric device, the crystal resonator 3 is an example of a piezoelectric resonator, and the integrated circuit element 5 is an example of an electronic element.

  The present invention is not limited to the above embodiment, and may be implemented in various aspects.

  The piezoelectric device is not limited to an oscillator having a vibrator and an oscillation circuit. In another aspect, the electronic element mounted on the vibrator and accommodated in the opening of the wiring board is not limited to the integrated circuit element including the oscillation circuit. For example, the piezoelectric device does not have an oscillation circuit, and may be a broad-sense vibrator having a narrow-sense vibrator 3 and appropriate electronic elements. In this case, in the element mounting member 11, the pair of element mounting pads 23 on which the vibration element 9 is mounted is not an electronic element pad (IC pad 26 in the embodiment) but any of the vibrator terminals 25. Or two. In addition, for example, a thermistor and / or a heater may be mounted in the opening and connected to the vibrator terminal 25 via the element mounting member 11. Further, the piezoelectric device is not limited to the one using crystal, and for example, ceramic may be used.

  When the piezoelectric device is an oscillator, its use or function may be set as appropriate. For example, the piezoelectric oscillator may be a clock oscillator, a voltage controlled oscillator (for example, VCXO), a temperature compensated oscillator (for example, TCXO), or a thermostatic oscillator. It may be an oscillator in a constant temperature bath (for example, OCXO). The number and arrangement of external terminals, vibrator pads, vibrator terminals, IC pads, and IC terminals may be appropriately set according to functions required for the piezoelectric oscillator.

  The specific configuration of the piezoelectric vibrator may be changed as appropriate. For example, the piezoelectric vibrating element may be of a tuning fork type having two vibrating arms, or a pair of extraction electrodes formed on a rectangular flat plate diagonal. For example, the element mounting member may have a frame portion made of metal.

  The wiring board may have not only the main surface but also a conductor layer parallel to the main surface inside. Further, the wiring board is not limited to a configuration having a size approximately equal to that of the vibrator in plan view. In other words, the wiring board is not limited to one that forms a shape like a so-called H-type package with the vibrator package. For example, the wiring board may have a relatively large area, and an appropriate electronic element may be mounted on the first main surface in parallel with the vibrator. For example, the wiring board may be one in which an electronic component such as a heater is mounted on the second main surface so as to cover the opening.

  The configuration of the connection conductor that connects the vibrator pad and the external terminal is not limited to that shown in the embodiment. For example, the connection conductor may be a conductor layer provided on the inner surface of a castellation (a recess in plan view) formed on the outside of the wiring board, or a metal filled in a through-hole penetrating the wiring board. There may be.

  The configuration of the surrounding portion is not limited to the configuration illustrated in the embodiment. For example, the surrounding portion may cover the surface on the opposite side of the wiring substrate of the vibrator, or the surface on the opposite side of the surrounding portion from the wiring substrate is more than the surface on the opposite side of the wiring substrate of the vibrator. The side surface of the surrounding part may be located inside the side surface of the wiring board 7.

  The method for manufacturing the piezoelectric device is not limited to the method exemplified in the embodiment. For example, the cutting may be performed from the surface side opposite to the wiring substrate of the surrounding portion, and is not limited to using a dicing blade, and may be performed using, for example, a laser.

  DESCRIPTION OF SYMBOLS 1 ... Crystal oscillator (piezoelectric device), 3 ... Crystal oscillator (piezoelectric vibrator), 5 ... Integrated circuit element (electronic element), 7 ... Wiring board, 8 ... Surrounding part, 37a ... 1st main surface, 37b ... 1st 2 principal surface, 37h ... opening, 37e ... through hole, 41 ... vibrator pad, 43 ... external terminal.

Claims (6)

A vibrator pad provided on one main surface, an external terminal provided on the other main surface connected to the vibrator pad, and a wiring board having an opening penetrating in the thickness direction;
A piezoelectric vibrator mounted on the vibrator pad so as to cover the opening;
An electronic element located in the opening and mounted on the piezoelectric vibrator;
An outer peripheral surface of the piezoelectric vibrator, and an enclosure portion made of an insulating material in close contact with a peripheral portion of the piezoelectric vibrator of the one main surface;
A piezoelectric device having The piezoelectric device according to claim 1, wherein a surface of the piezoelectric vibrator opposite to the wiring board is exposed from the surrounding portion. The piezoelectric device according to claim 2, wherein a surface of the piezoelectric vibrator opposite to the wiring substrate and a surface of the surrounding portion opposite to the wiring substrate are flush with each other. The wiring board is provided on the outer side of the piezoelectric vibrator in a plan view through the wiring board in the thickness direction, and is provided in the through hole to connect the vibrator pad and the external terminal. A connection conductor, and
The piezoelectric device according to claim 1, wherein the surrounding portion covers the through hole. A large number of wiring boards having a vibrator pad provided on one main surface, an external terminal connected to the vibrator pad provided on the other main surface, and an opening penetrating in the thickness direction are obtained. A step of providing, on the mother board, a piezoelectric vibrator mounted on the one main surface so as to cover the opening, and an electronic element located in the opening and mounted on the piezoelectric vibrator;
In the mother substrate provided with the piezoelectric vibrator, a molten insulating material is supplied to the one main surface to be solidified, and the peripheral portion of the one main surface of the piezoelectric vibrator, and Forming an insulating layer in close contact with the outer peripheral surface of the piezoelectric vibrator;
Cutting the mother substrate and the insulating layer into pieces by cutting from the other main surface side with a blade;
Manufacturing method of piezoelectric device having In the step of forming the insulating layer, the surface of the piezoelectric vibrator opposite to the wiring board and the surface of the insulating layer opposite to the wiring board are flush with each other. The method for manufacturing a piezoelectric device according to claim 5.

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