JP2009278399A - Piezoelectric device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To attain thickness reduction and cost reduction in a piezoelectric device in which electronic components such as a semiconductor circuit element are joined to a piezoelectric vibrator via a relay board. <P>SOLUTION: An IC chip 30 is joined to the piezoelectric vibrator sealed by joining a crystal vibration chip 20 in a package 10 via the relay board 50. The relay board 50 includes: IC connection terminals 55a, 55b provided on an insulating base material 51; first through-holes 63a, 63b for connection pierced through the insulating base material 51 directly under the IC connection terminals; and external terminals 57a, 57b on the side of the relay board. The IC chip 30 is connected to the IC connection terminals 55a, 55b exposed from the first through-holes 63a, 63b for connection of the relay board 50 via a bump 95. Then, external terminals 15a, 15b on the side of the vibrator provided on the bottom surface side of the package 10, and the external terminals 57a, 57b on the side of the relay board of the relay board 50 are joined to each other via a joining member 91. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a configuration for realizing a reduction in thickness and cost in a piezoelectric device in which an electronic component such as a semiconductor circuit element is bonded to a piezoelectric vibrator via a relay substrate.

  Conventionally, using a characteristic that a thin plate obtained by cutting a piezoelectric substrate such as quartz crystal at a predetermined angle and thickness has a specific resonance frequency, a voltage is applied to the electrodes provided on opposite surfaces of the thin plate, and the voltage is applied. 2. Description of the Related Art Piezoelectric devices in which a piezoelectric vibrating piece that vibrates due to the piezoelectric effect is bonded in a package and hermetically sealed are widely used. As the piezoelectric vibrating piece, for example, an AT-cut quartz vibrating piece that performs thickness-shear vibration using a thin plate obtained by cutting a piezoelectric substrate at a cut angle called an AT cut is used. As a piezoelectric device including such a piezoelectric vibrating piece, an electronic component such as a semiconductor circuit element having an oscillation circuit is bonded to a piezoelectric vibrator in which a piezoelectric vibrating piece is bonded and sealed in a package. Piezoelectric oscillators are widely used as a reference source for frequency or time.

  In recent years, there has been a strong demand for further downsizing of small-sized information communication devices such as mobile phones and other personal digital assistants (PDAs) that are widely used. Along with this, there is a growing demand for further miniaturization of piezoelectric devices mounted in information communication equipment. As a piezoelectric device that meets such demands, a piezoelectric device is proposed that is configured by joining an electronic component such as a semiconductor circuit element to a piezoelectric vibrator via a relay substrate (for example, Patent Document 1).

The piezoelectric device (crystal oscillator) described in Patent Document 1 includes a piezoelectric vibrator (a crystal vibrator with a case) in which a piezoelectric vibrating piece is bonded and sealed in a package, and an electronic device such as a semiconductor circuit element (integrated circuit). It is configured by joining components to each other via a relay substrate (flexible substrate).
On the outer bottom surface of the package, vibrator-side external terminals (connection terminals) for connection to the relay substrate are provided. In addition, a double-sided wiring board in which circuit wiring is formed on both sides of the insulating base material is used as the relay board, and the relay board side provided at a position corresponding to the vibrator-side external terminal of the package on one side An external terminal (connection terminal) is provided, and electronic component connection terminals such as circuit element connection terminals are provided on the other surface. An electronic component such as a semiconductor circuit element is bonded to a corresponding electronic component connection terminal of the relay substrate via a bonding member such as a conductive adhesive. The vibrator-side external terminal of the package and the relay board-side external terminal of the relay board are joined. A frame body made of a rigid rigid board is provided under the relay board so as to surround an electronic component such as a semiconductor circuit element. On the bottom side of the frame portion of the frame body, mounting terminals (external connection terminals) used when mounting the piezoelectric device on the external mounting substrate are provided, and the mounting terminals and the relay substrate are formed on the end surface of the frame body. The connection electrodes (end face external electrode portions) are connected.

JP 2000-252747 A

However, in the piezoelectric device described in Patent Document 1, since the double-sided wiring board is used as the relay substrate, the thickness is large, and the cost is high, which is disadvantageous for making the piezoelectric device thinner and lower in cost. there were.
Further, since the mounting terminals are formed on the frame provided below the relay substrate, there is a problem that the number of parts increases and the piezoelectric device is further disadvantageous in thickness.

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

  Application Example 1 A piezoelectric device according to this application example includes a piezoelectric vibration member having a vibrator-side external terminal that is sealed in a package and electrically connected to the piezoelectric vibration member on an outer bottom surface of the package. A piezoelectric device in which a child and a semiconductor circuit element having an electrode pad formed on a main surface are joined via a relay substrate, the relay substrate having an insulating base, and the insulating base Circuit wiring is formed on one surface facing the piezoelectric vibrator, the vibrator-side external terminal of the piezoelectric vibrator is joined on the circuit wiring, and the insulating base is the other facing the semiconductor circuit element A connection through hole penetrating from the surface to the one surface, the opening on the one surface side of the connection through hole is closed by the circuit wiring, and the electrode pad of the semiconductor circuit element is The opening of the circuit wiring The tool portion, characterized in that it is joined by a joining member via the connecting through hole.

According to the above configuration, even when the arrangement of the electrode pads of the semiconductor circuit element and the arrangement of the package-side external terminals of the package are different, the relay in which the connection through hole and the circuit wiring are formed in accordance with the arrangement. A substrate is used. Thus, the piezoelectric device can be configured by connecting the piezoelectric vibrator and the semiconductor circuit element without changing the arrangement of the vibrator-side external terminal of the package or the electrode pad of the semiconductor circuit element.
In addition, the electrode pads of the semiconductor circuit element are joined to a portion that closes the opening of the circuit wiring by a joining member via a connection through hole. Thereby, compared with the case where a double-sided wiring board is used, the mounting height of the semiconductor circuit element mounted on the relay board can be reduced by the thickness of the insulating base material. Therefore, it is possible to reduce the thickness of the piezoelectric device.
In addition, the relay board can be a single-sided wiring board. In this case, the manufacturing process of the relay board is simplified and can be manufactured at a lower cost than when using a double-sided wiring board, for example. A piezoelectric device in which a child and a semiconductor circuit element are connected by a relay substrate can be provided at low cost.

  Application Example 2 In the piezoelectric device according to the application example described above, the bonding member is a bump provided on the electrode pad.

  According to this configuration, when the semiconductor circuit element is mounted on the relay board, the bump is inserted from the connection through hole of the relay board and bonded to the circuit wiring, thereby mounting the relay board and the semiconductor circuit element. Can be made thinner and contribute to the thinning of the piezoelectric device.

  Application Example 3 In the piezoelectric device according to the application example, the joining member includes a metal via embedded in the connection through hole.

  According to this configuration, when the semiconductor circuit element is mounted on the relay substrate, the bump formed on the electrode pad of the semiconductor circuit element may be thin, or a conductive adhesive, an anisotropic conductive film, etc. If this bonding member is used in combination, it is possible to directly bond to the electrode pad. As a result, the bump forming process on the semiconductor circuit element can be simplified or omitted, so that the manufacturing cost of the semiconductor circuit element can be reduced and the cost of the piezoelectric device can be reduced.

  Application Example 4 In the piezoelectric device according to the application example, the insulating base material further includes a mounting terminal through hole penetrating from the one surface to the other surface, and the circuit wiring includes the mounting terminal. The mounting through hole is formed so as to close the opening on the one surface side, and an external mounting bump is provided in the mounting terminal through hole and is joined to the circuit wiring.

  According to this configuration, the piezoelectric device can be configured by connecting the piezoelectric vibrator and the semiconductor circuit element via the relay substrate in the same manner as the piezoelectric device of the above application example, and for the mounting terminal of the relay substrate. By forming the through hole and the circuit wiring in accordance with the electrode arrangement of the external mounting board on which the piezoelectric device is mounted, a piezoelectric device having mounting terminals corresponding to the electrode arrangement of the external mounting board can be provided.

Hereinafter, an embodiment of a piezoelectric device will be described with reference to the drawings.
1A and 1B illustrate a piezoelectric device according to this embodiment. FIG. 1A is a schematic plan view viewed from the piezoelectric vibrator side (upper surface side), FIG. 1B is a schematic cross-sectional view, and FIG. It is the model top view seen from the lower surface side. Note that, in the schematic plan view of (a), the lid arranged on the upper portion of the piezoelectric device is cut out and illustrated for convenience of explanation of the internal configuration of the crystal resonator. Also, in the schematic cross-sectional view of (b), the upper surface side of the package 10 from the first layer substrate 11 shows the cross section along the line AA of (a), and the lower surface side thereof is the BB line of (c). A line section is shown.
2A and 2B are schematic plan views of the crystal resonator package as seen from the bottom surface side (lower surface side). FIG. 2A shows the resonator-side external terminal and the upper side thereof. (B) illustrates the positional relationship between the vibrator-side external terminal and the relay board-side external terminal of the relay board disposed below. It is.

  As shown in FIG. 1, the piezoelectric device 1 includes a crystal resonator as a piezoelectric resonator in which a crystal resonator element 20 as a piezoelectric resonator element is joined inside a package 10, and a relay substrate 50 on the bottom side of the package 10. And an IC chip 30 as a semiconductor circuit element joined via the IC chip. In addition, a plurality of mounting bumps 59 a to 59 d as mounting terminals are provided at the corner portion of the relay substrate 50 that is the outer bottom portion of the package 10. A lid 19 is bonded to the upper surface of the package 10, and the crystal vibrating piece 20 is hermetically sealed inside the package 10.

〔Crystal oscillator〕
As shown in FIG. 1B, the package 10 includes a substantially rectangular flat plate-like first layer substrate 11, and a substantially rectangular frame-shaped second layer substrate 12 and a seal ring 18 on the first layer substrate 11. It is configured by sequentially laminating, whereby a recess is formed substantially in the center. Further, on the first layer substrate 11 serving as a concave bottom portion of the concave portion of the package 10, a plurality of vibration piece joint terminals 16a and 16b to which the crystal vibration piece 20 is joined are provided (see FIG. 1A). See also).

  As shown in FIG. 2, a plurality of transducer-side external terminals 15 a and 15 b to which the relay substrate 50 on which the IC chip 30 is mounted are bonded are provided on the bottom side of the package 10. The vibrator-side external terminals 15a and 15b are connected to the relay terminal portions 15c and 15d provided immediately below the above-described vibrating piece joining terminals 16a and 16b by inter-terminal wirings 17, respectively. The relay terminal portions 15c and 15d are connected to the corresponding resonator element joining terminals 16a and 16b by an in-layer wiring 45 such as a through hole. As a result, the vibrator-side external terminal 15 a is connected to the resonator element joining terminal 16 a via the intra-layer wiring 45, the relay terminal portion 15 c, and the inter-terminal wiring 17, and the vibrator-side external terminal 15 b is connected to the intra-layer wiring 45. Further, the resonator element connecting terminal 16 b is connected to the resonator element connecting terminal 16 b through the relay terminal portion 15 d and the inter-terminal wiring 17.

  The first layer substrate 11 and the second layer substrate 12 of the package 10 described above are made of a ceramic insulating material or the like. Further, the resonator element joining terminals 16a and 16b, the vibrator side external terminals 15a and 15b, the relay terminal portions 15c and 15d provided on the first layer substrate 11, and the inter-terminal wiring 17 connecting them or the intra-layer wiring In general, the wiring pattern such as 45 is formed by screen-printing and baking a metal wiring material such as tungsten (W) or molybdenum (Mo) on a ceramic insulating material, and nickel (Ni), gold (Au), or the like thereon. It is formed by plating.

  In FIG. 1, as the crystal vibrating piece 20 bonded to the concave bottom portion of the concave portion of the package 10 in FIG. An example using an AT-cut quartz crystal vibrating piece made up of the AT-cut quartz plate 21 will be described. An excitation electrode 25 is provided on one main surface of the AT-cut quartz plate 21 and is connected to a connection electrode 26 a provided near one end of the AT-cut quartz plate 21. Although not shown, the other main surface of the AT-cut quartz plate 21 is provided with an excitation electrode which is a counter electrode of the excitation electrode 25, and the excitation electrode is provided in the vicinity of the connection electrode 26a. It is connected to the electrode 26b. Such an electrode or wiring is formed, for example, by depositing an AT-cut quartz plate 21 cut out from a quartz substrate and then using, for example, nickel (Ni) or chromium (Cr) as an underlayer, and depositing, for example, gold on the substrate by vapor deposition or sputtering. An electrode layer made of (Au) can be formed, followed by patterning using photolithography.

  The crystal vibrating piece 20 has connection electrodes 26 a and 26 b formed at one end thereof aligned with the corresponding vibrating piece joining terminals 16 a and 16 b of the package 10 and joined by a joining member such as a conductive adhesive 96. . Thus, the quartz crystal vibrating piece 20 is cantilevered with a gap so that the other end side where the excitation electrode 25 is formed does not come into contact with the first layer substrate 11. In general, the conductive adhesive 96 is made of a resin such as polyimide, silicon, or epoxy mixed with silver (Ag) filament or nickel (Ni) powder.

  On the second layer substrate 12 of the package 10, for example, a metal lid 19 is seam welded via a seal ring 18 formed by punching an iron-nickel (Fe—Ni) alloy or the like into a frame shape. The crystal vibrating piece 20 bonded in the package 10 is hermetically sealed.

〔Relay board〕
Here, the relay substrate 50 that relays the connection between the crystal resonator and the IC chip 30 will be described with reference to the drawings. 3A and 3B are diagrams for explaining the relay substrate. FIG. 3A is a schematic plan view seen from the upper surface side to which the crystal resonator is joined, and FIG. 3B is a schematic plan view seen from the lower surface side to which the IC chip is joined. FIG. FIG. 4 illustrates two forms for efficiently manufacturing the relay board 50. FIG. 4A is a schematic plan view illustrating the sheet-like relay board sheet as viewed from the lower surface side. b) is a schematic plan view illustrating a hoop-shaped relay board tape as viewed from the lower surface side.

  In FIG. 3, a relay substrate 50 is a circuit such as a connection terminal or wiring between terminals made of a wiring metal material such as copper on one main surface (upper surface) of an insulating base material 51 having heat resistance such as polyimide resin. This is a single-sided wiring board on which wiring is formed. The relay board 50 according to the present embodiment includes, as connection terminals, IC connection terminals 55a to 55f as semiconductor circuit element connection terminals used for connection to the IC chip 30, and relay board side external terminals used for connection to the crystal resonator. 57a and 57b, and output side connection terminals 56a to 56d connected to the plurality of mounting bumps 59a to 59d of the piezoelectric device 1.

  The IC connection terminals 55a to 55f are provided at positions corresponding to the plurality of electrode pads 35a to 35f (see FIG. 1C) provided on the upper surface of the IC chip 30. In the present embodiment, among the IC connection terminals 55a to 55f, the IC connection terminals 55a and 55b connected to the electrode pads 35a and 35b drawn from the circuit for driving the crystal resonator of the IC chip 30 are inter-terminal wirings, respectively. To the relay board side external terminals 57a and 57b. Further, the IC connection terminals 55c to 55f connected to the electrode pads 35c to 35f drawn from the circuit in the IC chip 30 that generates an external output signal of the piezoelectric device 1 are output side connection terminals 56a via inter-terminal wirings. To 56d, respectively.

As described above, each circuit wiring provided on the relay substrate 50 is aligned and bonded to the bottom surface side of the package 10 in the arrangement shown in FIG. 2B in the piezoelectric device 1. That is, the relay board side external terminals 57a and 57b connected to the IC connection terminals 55a and 55b are arranged to be joined to the corresponding vibrator side external terminals 15a and 15b of the package 10, respectively. As a result, the resonator element joining terminals 16a and 16b (see FIG. 2A) of the package 10 correspond to the corresponding electrode pads 35a and 35b (see FIG. 2A) of the IC chip 30 via the IC connection terminals 55a and 55b of the relay substrate 50. 1 (see FIG. 1C).
Note that the relay substrate 50 may be formed with an insulating film on the surface on which the crystal resonator is disposed so that the relay substrate side external terminals 57a and 57b are exposed. Thereby, it is possible to prevent the transducer-side external terminals 15a and 15b and the circuit wiring other than the relay board-side external terminals 57a and 57b of the relay board 50 from being short-circuited.

  As shown in FIG. 3, first connection through holes 63 a to 63 f that are provided for connection to the IC chip 30 are provided through the insulating base material 51 immediately below the IC connection terminals 55 a to 55 f. Each of the first connection through holes 63a to 63f is formed in a size smaller than the corresponding IC connection terminals 55a to 55f, and one opening (the opening on the upper side of the insulating base 51) is formed. The IC connection terminals 55a to 55f are closed. As a result, the back surfaces of the corresponding IC connection terminals 55a to 55f are exposed from the other openings of the first connection through holes 63a to 63f (the openings on the lower side of the insulating base 51). .

  Similarly, second insulating through holes 53a to 53d, which are portions where the mounting terminals of the piezoelectric device 1 are provided, are provided in the insulating base material 51 immediately below the output side connection terminals 56a to 56d. . Each of the second connection through holes 53a to 53d is formed in a size smaller than the corresponding output side connection terminals 56a to 56d, and one opening (the opening on the upper side of the insulating base 51) is formed. The output side connection terminals 56a to 56d are closed. As a result, the back surfaces of the corresponding output side connection terminals 56a to 56d are exposed from the other openings of the second connection through holes 53a to 53d (the openings on the lower side of the insulating base 51). Yes.

Each of the second connection through holes 53a to 53d is provided so that one end portion is connected to the output side connection terminals 56a to 56d and the other end side protrudes outward from the second connection through holes 53a to 53d. Mounting bumps 59a to 59d are formed as mounting terminals. The mounting bumps 59a to 59d have a height for preventing the IC chip 30 bonded to the outer bottom surface side of the piezoelectric device 1 from coming into contact with the external mounting substrate when the piezoelectric device 1 is bonded to the external mounting substrate. (See FIG. 1B).
As a material for the mounting bumps 59a to 59d, for example, a conventional metal bump material such as gold or solder can be used. In addition to this, the surface of the core member made of metal or resin is made of gold or solder. A material in which a metal film for bonding such as the above is formed can be used.

The relay substrate 50 having the above-described configuration can be manufactured by the steps described below.
First, a metal foil for electrode formation such as a copper foil having a predetermined thickness is bonded onto one main surface of the insulating base 51, and then the IC connection terminals 55a to 55f and the relay board side external terminal 57a. 57b, output side connection terminals 56a to 56d, and circuit wirings such as inter-terminal wirings for connecting these terminals are formed by photolithography. In addition, as a formation method of circuit wiring, after laminating | stacking the metal for electrode formation by plating or vapor deposition on the insulating base material 51, this is patterned by photolithography, sputtering method etc. on the insulating base material 51 etc. It is also possible to use a so-called additive method in which a thin metal layer is formed and then patterned, and only a necessary portion is plated to form a circuit wiring pattern.

Next, the first connection through holes 63a to 63f and the second connection through holes are irradiated by irradiating laser light adjusted to a predetermined wavelength, output, or spot diameter from the lower surface side of the insulating base 51. 53a to 53d are formed. Thus, by adjusting the wavelength, output, and the like of the laser light to be irradiated to a predetermined range according to the insulating base material 51 and the circuit wiring forming material, the IC connection terminals 55a to 55f and the output side connection terminals 56a to 56d. The first connection through-holes 63a to 63f and the second connection through-holes 53a to 53d can be formed by selectively removing only the insulating base 51 without substantially invading the back surface side of the first connection through-hole. .
Next, mounting bumps 59a to 59d are formed on the second connection through holes 53a to 53d side of the output side connection terminals 56a to 56d. As the mounting bumps 59a to 59d, a metal ball such as gold or solder having a predetermined size, or a spherical bump material in which a bonding metal film is formed on the surface of a spherical core such as metal or resin is used for the second connection. It can form by joining to the output side connection terminals 56a-56d from the through-holes 53a-53d side for use.
Note that the mounting bumps 59a to 59b can be provided after the relay substrate 50 on which the IC chip 30 is mounted is bonded to the crystal resonator.
The relay substrate 50 can be manufactured by the steps described above.

In the manufacturing process of the relay substrate 50 described above, a plurality of relay substrates 50 are continuously formed at equal intervals on a large base sheet made of the material of the insulating base 51 or a hoop-shaped tape base. Can be efficiently manufactured by cutting the substrate into individual relay boards 50.
FIG. 4A shows a relay substrate sheet 351 manufactured by continuously connecting a relay substrate 50 vertically and horizontally to a large base sheet 352 in a matrix. As described above, a plurality of relay boards 50 can be obtained by forming the plurality of relay boards 50 on the base sheet 352 and then cutting along the cutting lines 359.
FIG. 4B shows a relay substrate tape 451 formed by continuously connecting the relay substrate 50 to a hoop-shaped tape base material 452. By cutting the relay substrate tape 451 along the cutting line 459, a plurality of individual relay substrates 50 can be obtained.
In FIG. 4B, an example in which a single row of relay substrates 50 is continuously formed on the tape base material 452 has been described. However, two or more rows of relay substrates 50 are continuously formed on a wide tape base material. In this case, the relay substrate 50 can be manufactured more efficiently.

[Piezoelectric device]
Next, the piezoelectric device 1 of this embodiment configured by bonding the IC chip 30 to a crystal resonator using the above-described relay substrate 50 will be described in detail.
In FIG. 1B, the IC chip 30 is bonded to the lower surface side of the relay substrate 50 via a plurality of bumps 95 as bonding members.
More specifically, the back surfaces of the IC connection terminals 55a and 55b so that the plurality of bumps 95 provided on the IC chip 30 are inserted into the corresponding first connection through holes 63a and 63b of the relay substrate 50. It is joined to the side. The bumps 95 are provided in advance on the plurality of electrode pads 35a to 35f of the IC chip 30 shown in FIG. 1C, and among these, the electrode pads 35a and 35b are shown in the cross-sectional view of FIG. The state in which the bumps 95 provided on the IC are connected to the IC connection terminals 55a and 55b is shown. Similarly to these, the bumps provided on the other electrode pads 35c to 35f are IC connection terminals 55c to 55f exposed from the corresponding first connection through holes 63c to 63f (see FIG. 3). Are respectively joined to the back surface side (not shown). The plurality of bumps 95 are made of, for example, gold or solder. After the bumps 95 and the corresponding IC connection terminals 55a to 55f of the relay substrate 50 are aligned, a thermocompression bonding tool having a predetermined temperature and pressure is used. Bonding can be performed by so-called face-down bonding in which the IC chip 30 is pressed from the back side and heated and pressed.
Although not shown, the bonding strength between the relay substrate 50 and the IC chip 30 is obtained by filling the gap between the relay substrate 50 and the IC chip 30 bonded as described above with an underfill material and solidifying the gap. It is good also as a structure which secures and improves impact resistance and reliability.
The bump 95 is not limited to a metal bump made of gold, solder, or the like, and may be a resin core bump or a metal core bump in which a conductive film is formed on the surface of a resin or metal core. The IC chip 30 may be bonded to the relay substrate 50 using another bonding member such as a conductive adhesive.

The relay board side external terminals 57a and 57b of the relay board 50 to which the IC chip 30 is bonded are aligned with the corresponding vibrator side external terminals 15a and 15b provided on the bottom surface of the crystal oscillator package 10, for example, conductive They are joined via joining members 91 such as adhesive. As the bonding member 91, solder or the like may be used in addition to the conductive adhesive. Furthermore, in this embodiment, in order to reinforce the bonding between the relay substrate 50 and the crystal resonator, the thermosetting type or ultraviolet curing type non-conductive adhesive 81 is bonded and fixed. The adhesive 81 connects the relay board 50 and the package 10 after connecting the relay board side external terminals 57a and 57b of the relay board 50 and the vibrator side external terminals 15a and 15b of the package 10 via the joining members 91, respectively. And then solidified by heating or irradiation with ultraviolet rays.
With the configuration described above, the IC chip 30 is bonded to the crystal resonator via the relay substrate 50, and the piezoelectric device 1 having the mounting bumps 59a to 59d as mounting terminals on the outer bottom portion is formed.

  According to the piezoelectric device 1 of the above embodiment, even when the arrangement of the plurality of electrode pads 35a to 35f of the IC chip 30 and the arrangement of the vibrator-side external terminals 15a and 15b of the package 10 are different, the arrangement is not limited. A relay board 50 having the combined first connection through holes 63a to 63f and IC connection terminals 55a to 55f and relay board side external terminals 57a and 57b is used. Thus, the piezoelectric device 1 is configured by connecting the crystal resonator and the IC chip 30 without changing the arrangement of the vibrator-side external terminals 15a and 15b of the package 10 or the electrode pads 35a to 35f of the IC chip 30. can do.

  Further, in the piezoelectric device 1 of the above embodiment, mounting bumps 59a to 59d provided on the relay substrate 50 are used as mounting terminals used when mounting on the external mounting substrate. The arrangement of the mounting bumps 59a to 59d can be determined by the output side connection terminals 56a to 56d and the second connection through holes 53a to 53d of the relay board 50 provided in accordance with the electrode arrangement of the external mounting board. Therefore, only the arrangement of the output side connection terminals 56a to 56d and the second connection through holes 53a to 53d of the relay board 50 is changed according to the arrangement of the connection electrodes of the external mounting board on which the piezoelectric device 1 is mounted. Can respond.

  In addition, since the relay board 50 can be formed of a single-sided wiring board by including the first connecting through holes 63a to 63f and the second connecting through holes 53a to 53d, for example, when using a double-sided wiring board As compared with the above, the manufacturing process of the relay substrate 50 can be simplified and manufactured at a low cost, and the cost of the piezoelectric device 1 can be reduced.

Moreover, in the said embodiment, the bump 95 previously provided on the electrode pads 35a-35f of IC chip 30 is used as a joining member which connects the relay substrate 50 and IC chip 30. FIG.
Thus, when the IC chip 30 is mounted on the relay substrate 50, the bump 95 is inserted into the first connection through holes 63a to 63f of the relay substrate 50 and bonded to the IC connection terminals 55a to 55f. The structure can be reduced in thickness.

  The piezoelectric device described in the above embodiment can be implemented as the following modifications.

(Modification 1)
In the above-described embodiment, the example in which the mounting bumps 59 a to 59 d are provided on the relay substrate 50 and are used as the mounting terminals of the piezoelectric device 1 has been described. However, the present invention is not limited to this, and the mounting terminal of the piezoelectric device may be provided in a crystal resonator package.

  5 to 7 illustrate a modification of the piezoelectric device in which a mounting terminal is provided in a crystal resonator package. FIG. 5A is a schematic cross-sectional view, and FIG. 5B is a schematic view viewed from the bottom side. It is a top view. FIG. 6 is a schematic plan view of the relay substrate used in the piezoelectric device of the present modification as viewed from the upper surface side, and FIG. 7 is a schematic plan view of the package used in the piezoelectric device of the present modification as viewed from the bottom surface side. It is. 5A, the section above the first layer substrate 111 of the package 110 shows the same section as the section along the line AA of FIG. 1A, and is below the first layer substrate 111. FIG. 5 shows a cross section taken along the line CC of FIG. Moreover, the same code | symbol is attached | subjected about the structure same as the piezoelectric device 1 of the said embodiment among the structures of the piezoelectric device of this modification, and description is abbreviate | omitted.

  As shown in FIG. 5, the piezoelectric device 100 is bonded to a quartz crystal resonator unit 20 in which a crystal vibrating piece 20 is bonded and hermetically sealed, and to an outer bottom portion of the package 110 via a relay substrate 150. IC chip 30 as a semiconductor circuit element. In addition, a plurality of mounting terminals 159 a to 159 d used for connecting the piezoelectric device 100 and an external mounting substrate are provided on the outer bottom portion of the package 110.

  In FIG. 5, a package 110 has a substantially rectangular flat first layer substrate 111, and a substantially rectangular frame-shaped second layer substrate 12 and a seal ring 18 are sequentially stacked on the first layer substrate 111. Further, a bottom substrate 113 having a substantially rectangular frame shape is laminated on the surface (lower surface side) opposite to the surface on which the second layer substrate 12 is laminated of the first layer substrate 111. Thus, two recesses are formed in the package 110 at approximately the center on the upper surface side and the lower surface side of the first layer substrate 111, respectively.

The concave portion on the upper side of the package 110 has the same configuration as that of the package 10 of the above-described embodiment. , 16b are provided.
A first vibrator-side external terminal 115a to which the IC chip 30 is connected via a relay substrate 150 (to be described later) on the lower surface side of the first layer substrate 111, which is a concave bottom portion of the lower recess of the package 110. , 115f are provided. The first vibrator-side external terminals 115 a and 115 f are connected to the corresponding resonator element joining terminals 16 a and 16 b by the in-layer wiring 45 penetrating in the first layer substrate 111. A plurality of mounting terminals 159 a to 159 d for mounting the piezoelectric device 100 on the external mounting substrate are provided on the frame portion of the bottom substrate 113 that forms the bottom surface of the package 110.

  As shown in FIG. 7, on the bottom surface side of the first layer substrate 111, the first vibrator-side external terminals 115a and 115f, the first vibrator-side external terminals 115a and 115f, and the resonator element joining terminal 16a are provided. 16b (see FIG. 1A and FIG. 5A), the first relay terminal portions 115c and 115d that relay the connection, and the output side connection terminals 158a to 158d corresponding to the mounting terminals 159a to 159d described above. And second vibrator side external terminals 115e and 115f connected to the output side connection terminals 158a to 158d.

Next, the relay substrate 150 that relays the connection between the crystal resonator and the IC chip 30 in the piezoelectric device 100 of the present modification will be described.
As shown in FIG. 6, the relay substrate 150 includes a plurality of ICs used for connection to the IC chip 30 provided on one main surface (upper surface) of the insulating base material 151 in the same manner as the relay substrate 50 of the above embodiment. First relay board side external terminals 157a and 157b used for connection between the connection terminals 55a to 55f and the crystal resonator, and second relay board side external terminals 157c to 157f connected to the mounting terminals 159a to 159d. Is provided. In this modified example, among the IC connection terminals 55a to 55f, the IC connection terminals 55a and 55b connected to the electrode pads corresponding to the circuit for driving the crystal resonator of the IC chip 30 correspond to each other through the inter-terminal wiring. IC connection terminals 55c connected to the electrode pads 35c to 35f connected to the first relay board side external terminals 157a and 157b, respectively, and drawn from the circuit in the IC chip 30 that generates the external output signal of the piezoelectric device 100. To 55d are connected to corresponding second relay board side external terminals 157c to 157f through inter-terminal wirings, respectively.
In addition, first insulating through holes 63a to 63f are formed in the insulating base material 151 immediately below the IC connection terminals 55a to 55f of the relay board 150 in the same manner as the relay board 50 of the above embodiment. Yes. Thereby, it is possible to connect the electrode pads 35 a to 35 f of the IC chip 30 and the corresponding IC connection terminals 55 a to 55 f of the relay substrate 50 from the lower surface side of the relay substrate 150.

In FIG. 7, a substantially rectangular frame-shaped bottom substrate 113 stacked on the lower surface side of the package 110, and a lower surface side of the first layer substrate 111 that becomes a concave bottom portion of a recess formed by the bottom substrate 113. Each relay substrate 150 on which the IC chip 30 to be bonded is mounted is illustrated by a virtual line (two-dot chain line).
On the lower surface side of the first layer substrate 111 of the package 110, the first relay substrate side external terminals 157 a and 157 b drawn from the IC connection terminals 55 a and 55 b of the relay substrate 150 correspond to the first layers corresponding to the first layer substrate 111. The vibrator-side external terminals 115a and 115b are arranged so as to be joined respectively. The second relay board side external terminals 157c to 157f drawn out from the IC connection terminals 55c to 55f of the relay board 150 are respectively corresponding to the first relay terminal portions 115c and 115d and the second relay terminal portions 115c and 115d of the first layer board 111. The transducer-side external terminals 115e and 115f are arranged so as to be joined respectively. The first relay terminal portions 115c and 115d and the second vibrator-side external terminals 115e and 115f are output-side connection terminals 158a provided at positions overlapping the corresponding mounting terminals 159a to 159d of the bottom substrate 113 in plan view. To 158d and inter-terminal wirings. Then, the output side connection terminals 158 a to 158 d of the first layer substrate 111 and the corresponding mounting terminals 159 a to 159 d of the bottom side substrate 113 are connected to the inner layer wirings 145 a to 155 a through holes or the like penetrating the bottom side substrate 113. 145d, respectively.

Next, the piezoelectric device 100 of the present modification example configured using the package 110 and the relay substrate 150 described above will be described in detail.
In FIG. 5, similarly to the piezoelectric device 1 of the above-described embodiment, the crystal vibrating piece 20 is joined to the concave bottom portion of the upper concave portion of the package 110 in a cantilevered state, and the second layer substrate of the package 110. The crystal resonator element 20 is hermetically sealed in the package 110 by the lid 19 being joined to the top 12 via the seal ring 18.

  In FIG. 5, the IC chip 30 is bonded to the back surface side (lower surface side) of the relay substrate 150 via a plurality of bumps 95. Specifically, the bumps 95 provided on the plurality of electrode pads 35 a and 35 f of the IC chip 30 are exposed from the corresponding first connection through holes 63 a and 63 b of the relay substrate 150. It is joined to the back side. Similarly, the bumps provided on the electrode pads 35c to 35f of the IC chip 30 are respectively joined to the IC connection terminals 55c to 55f exposed from the first connection through holes 63c to 63f shown in FIG. (Not shown).

In FIG. 5, the first relay board side external terminal 157a and the second relay board side external terminal 157f of the relay board 150 to which the IC chip 30 is bonded are provided on the bottom surface of the package 110 of the crystal resonator. The first vibrator-side external terminal 115a and the second vibrator-side external terminal 115f are aligned with each other and connected via a joining member 91 such as a conductive adhesive. Similarly, the other vibrator side external terminals of the package 110 described above with reference to FIG. 7 and the corresponding relay board side external terminals of the relay board 150 are respectively connected via the joining members 91. (Not shown).
Further, in this modification, the gap between the relay substrate 150 and the crystal resonator is filled with a non-conductive adhesive 81 and solidified, thereby reinforcing the bonding between the relay substrate 150 and the crystal resonator. ing.

With the configuration described above, the IC chip 30 is bonded to the crystal resonator via the relay substrate 150, and the piezoelectric device 100 including the mounting terminals 159a to 159d on the outer bottom portion is formed.
In the configuration of the piezoelectric device 100 of this modification, a sealing material made of an insulating resin so as to cover part or all of the relay substrate 150 and the IC chip 30 bonded in the recess on the lower surface side of the package 110. It is good also as a structure which applies and fills and seals. In this way, each connection portion between the IC chip 30 and the relay substrate 150 or between the relay substrate 150 and the package 110 can be reinforced and protected from external stresses such as impact and heat. The impact resistance and reliability of the device 100 can be improved.

  According to the piezoelectric device 100 of the first modified example, similarly to the piezoelectric device 1 of the above-described embodiment, by using the relay substrate 150 that can be changed in design relatively easily, the outside of the package 110 on the first vibrator side Without changing the arrangement of the terminals 115a and 115b or the electrode pads 35a to 35f of the IC chip 30, the crystal device and the IC chip 30 can be connected to constitute the piezoelectric device 100.

(Modification 2)
In the piezoelectric devices 1 and 100 of the above-described embodiment and the first modification, the bump 95 as a bonding member is provided on the electrode pad 35 of the IC chip 30, and the first through holes 63 a to 63 f of the relay boards 50 and 150 are connected. Each bump 95 is joined to the back surface of the exposed IC connection terminals 55a to 55f. Not limited to this, a metal material is buried in each connection through hole of the relay substrate to form a so-called metal via (via hole), and this metal via is used as a connection member to the IC chip 30 as at least a part thereof. It is good also as a structure.
FIG. 8 is a partial cross-sectional view illustrating, in an enlarged manner, a portion where an IC chip is bonded using a relay substrate in which metal vias are provided in connection through holes in a piezoelectric device.

  As shown in FIG. 8, the relay substrate 250 of the present modified example penetrates the plurality of IC connection terminals 255a and 255b provided on the insulating base 251 and the insulating base 251 of these IC connection terminals 255a and 255b. Connection through-holes 263a and 263b. The connection through holes 263a and 263b include metal vias 245a and 245b, which are formed by filling a metal via material such as copper with a plating method, for example, and corresponding IC connection terminals 255a and 255b. It is provided in a connected state.

  The IC chip 30 is bonded to the metal vias 245a and 245b of the relay substrate 250 via bonding members 195 provided on the corresponding electrode pads 35a and 35b. At this time, the bonding member 195 may be a bump provided in advance on each electrode pad of the IC chip 30, or may be a conductive adhesive or the like.

  According to the relay substrate 250 of the second modification, the bonding member 195 such as a bump formed on each electrode pad 35a, 35b of the IC chip 30 when the IC chip 30 is mounted on the relay substrate 250 is thin. In addition, by using joint members such as a conductive adhesive and an anisotropic conductive film, it is possible to directly join the electrode pads 35a and 35b without providing bumps. As a result, the bump forming process of the IC chip 30 can be simplified or omitted, so that the manufacturing cost of the IC chip 30 can be reduced and the cost of the piezoelectric device can be reduced.

  Although the embodiments of the present invention made by the inventor have been specifically described above, the present invention is not limited to the above-described embodiments and modifications thereof, and various modifications can be made without departing from the spirit of the present invention. It is possible to make changes.

For example, in the piezoelectric devices 1 and 100 of the above-described embodiment and the modification, the example in which the crystal vibrating piece 20 including the substantially rectangular AT-cut quartz plate 21 is used as the piezoelectric vibrating piece has been described. However, the present invention is not limited to this, and other types of crystal resonator elements such as a crystal resonator element made of a crystal plate cut at another cut angle, a tuning fork type crystal oscillator element, or another piezoelectric resonator element such as a SAW resonator are used. Even if it is used, the same effects as those described in the piezoelectric devices of the embodiment and the modified example are obtained.
In addition to quartz, materials for the piezoelectric resonator element include aluminum nitride (AlN), lithium niobate (LiNbO ₃ ), lithium tantalate (LiTaO ₃ ), lead zirconate titanate (PZT), lithium tetraborate (Li ₂ B ₄ O ₇ ) or a piezoelectric vibrating piece made of a piezoelectric material formed by laminating a thin film piezoelectric material such as aluminum nitride or tantalum pentoxide (Ta ₂ O ₅ ) on a glass substrate. You can also.

In the embodiment and the modification, the crystal vibrating piece 20 as the piezoelectric vibrating piece is bonded onto the vibrating piece connecting terminals 16 a and 16 b provided at the concave bottom portions of the concave portions formed in the packages 10 and 110. Explained. However, the present invention is not limited to this, and a configuration may be adopted in which a plurality of steps are provided in the concave portion of the package, and a vibrating piece joining terminal is provided on the step to join the piezoelectric vibrating piece. In this way, the free end side on which the excitation electrode of the piezoelectric resonator element is provided can be floated by the height of the step provided with the resonator element joint terminal. It is possible to avoid problems such as the piece colliding with the package and being damaged, and the impact resistance of the piezoelectric device can be improved.
Further, the packages 10 and 110 do not have the laminated structure described in the above-described embodiment and modifications, but may be formed in an integrated form from the beginning.

  In the embodiment and the modification, nickel (Ni) or chromium (Cr) is deposited or deposited on the base layer as a metal material for forming the electrodes of the crystal vibrating piece 20, the inter-electrode wiring, or the routing wiring. An example in which an electrode layer made of, for example, gold (Au) is formed by sputtering has been described. For example, a metal material such as titanium (Ti), tantalum (Ta), tungsten (W), or aluminum (Al) can be used. Magnesium (Mg) or the like can also be used.

  In the above-described embodiment and modification, the example in which the IC chip 30 as a semiconductor circuit element is bonded to the relay boards 50, 150, and 250 has been described. However, the present invention is not limited to this, and other electronic components such as a chip capacitor and a chip resistor may be joined and mounted on the relay boards 50, 150 and 250 in addition to the IC chip 30.

  In the above-described embodiment and modification, the use of the piezoelectric devices 1 and 100 is not particularly described. However, it is of course possible to use both the oscillator that oscillates the reference frequency of the signal and the oscillator that oscillates the reference signal of time. Alternatively, it can be used alone as an oscillator that oscillates a reference frequency, or can be used alone as an oscillator that oscillates a reference signal of time.

(A) is a schematic plan view of the piezoelectric device viewed from the piezoelectric vibrator side (upper surface side), (b) is a schematic cross-sectional view, and (c) is a schematic plan view viewed from the bottom surface side (lower surface side). (A), (b) is the model top view which looked at the package from the bottom face side (lower surface side). (A) is a schematic top view which looked at the relay board | substrate from the upper surface side, (b) is a schematic top view which looked at the lower surface side. (A) is a schematic plan view of a sheet-like relay board sheet as seen from the lower surface side, and (b) is a schematic plan view of a hoop-like relay board tape as seen from the lower surface side. (A) is a schematic cross-sectional view of the piezoelectric device of Modification 1, and (b) is a schematic plan view seen from the bottom surface side (lower surface side). The schematic plan view which looked at the relay substrate used for the piezoelectric device of the modification 1 from the upper surface side. The schematic plan view which looked at the package used for the piezoelectric device of the modification 1 from the bottom face side. The fragmentary sectional view which expands and demonstrates the part which joined the semiconductor circuit element using the relay substrate provided with the metal via in the piezoelectric device of the modification 2.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1,100 ... Piezoelectric device 10, 110 ... Package, 11, 111 ... 1st layer board | substrate, 12 ... 2nd layer board | substrate, 15a, 15b, 115a, 115b ... Vibrator side external terminal, 16a, 16b ... Vibrating piece joining Terminals, 18 ... Seal ring, 19 ... Lid, 20 ... Quartz vibrating piece as piezoelectric vibrating piece, 21 ... AT cut quartz plate, 25 ... Excitation electrode, 26a, 26b ... Connection electrode, 30 ... IC chip as semiconductor circuit element , 35a to 35f ... electrode pads, 45, 145a to 145d ... intra-layer wiring, 50, 150, 250 ... relay boards, 51, 151, 251 ... insulating base materials, 53a to 53d ... second connection through holes, 55a 55f, 255a, 255b ... IC connection terminals as semiconductor circuit element connection terminals, 56a-56d ... output side connection terminals, 57a, 57b ... relay board side external ends , 59a to 59d: mounting bumps as mounting terminals, 63a to 63f ... first connection through holes, 91, 195 ... bonding members, 95 ... bumps as bonding members, 96 ... conductive adhesive as bonding members , 113 ... bottom substrate, 115a, 115b ... first vibrator side external terminal, 115e, 115f ... second vibrator side external terminal, 157c to 157f ... second relay board side external terminal, 158a to 158d ... Output side connection terminals, 159a to 159d, mounting terminals, 245a, 245b, metal vias as bonding members, 263a, 263b, through holes for connection, 351, relay board sheet, 451, relay board tape.

Claims (4)

A semiconductor circuit having a piezoelectric vibrator having a vibrator-side external terminal sealed in a package and electrically connected to the piezoelectric vibrator on the outer bottom surface of the package, and an electrode pad formed on the main surface A piezoelectric device in which an element is bonded via a relay substrate,
The relay substrate has an insulating base;
The insulating base is formed with circuit wiring on one surface facing the piezoelectric vibrator, and the vibrator-side external terminal of the piezoelectric vibrator is joined on the circuit wiring,
The insulating base is formed with a connection through-hole penetrating from the other surface facing the semiconductor circuit element to the one surface, and the opening on the one surface side of the connection through-hole is formed by the circuit wiring. Blocked,
The piezoelectric device, wherein the electrode pad of the semiconductor circuit element is bonded to a portion that closes the opening of the circuit wiring by a bonding member through the connection through hole. The piezoelectric device according to claim 1,
The piezoelectric device, wherein the bonding member is a bump provided on the electrode pad. The piezoelectric device according to claim 1,
The piezoelectric device, wherein the joining member includes a metal via embedded in the connection through hole. The piezoelectric device according to any one of claims 1 to 3,
The insulating substrate further has a mounting terminal through-hole penetrating from the one surface to the other surface;
The circuit wiring is formed so as to block the opening on the one surface side of the mounting terminal through-hole,
An external mounting bump is provided in the mounting terminal through-hole, and is bonded to the circuit wiring.

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