JP2010263530A - Electronic component and piezoelectric vibrator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electronic component and a piezoelectric vibrator which reliably connects a lead-out electrode and a through electrode. <P>SOLUTION: The piezoelectric vibrator 10 is formed by mounting a piezoelectric vibration chip 14 having excitation electrodes (first and second excitation electrodes 26, 28) on a base substrate 42. The base substrate 42 includes through holes (first and second through holes 44, 46) formed on positions facing the piezoelectric vibration chip 14 and through electrodes (first and second through electrodes 52, 54) for sealing the through holes 44, 46. The piezoelectric vibration chip 14 includes projections (first and second projections 36, 38) and conductive films (first and second metal films 48a, 50a, etc.) formed on the surfaces of the projections 36, 38 and electrically connected to the excitation electrodes 26, 28 on the main surface of the piezoelectric vibration chip 14, which faces the through holes 44, 46, and is configured so that the conductive films formed on the surfaces of the projections 36, 38 penetrate through the aperture surfaces of the through holes 44, 46, which face the piezoelectric vibration chip 14. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an electronic component such as a piezoelectric vibrator or a force detection element having a laminated structure that is bonded by direct bonding, and particularly in connection of an electrical connection between a terminal electrode of an intermediate layer and a through electrode that penetrates a base substrate. It is related with the technology which improves the nature.

As mobile communication devices and mobile phones represented in recent years have become smaller, lighter and higher in frequency for personal mobile phones, piezoelectric vibrators and filters used in them have been required to be further reduced in size and frequency. ing. In order to meet this demand, conventional piezoelectric parts have been rapidly demanded to be applied to smaller and thinner packages.
On the other hand, piezoelectric elements such as crystal resonators, crystal filters, and SAW filters may be damaged by changes in ambient temperature and humidity, or by fine foreign substances, and may be damaged by mechanical vibration or impact. Cheap. For this reason, the above-mentioned element is sealed for use in a package.

  In the conventional package, a package is formed for each element. On the other hand, after a plurality of elements are cut out at the same time, the package is sealed and then cut into individual elements (chips). There is also proposed a technology for making a packaged chip. In this case, the package is manufactured by the laminated structure of the wafers, but it is necessary to perform electrical connection between electrodes existing in different wafers with high reliability.

  FIG. 12 shows a piezoelectric vibrator according to the first prior art. As shown in FIG. 12, Patent Document 1 discloses a crystal piece 203 having an excitation electrode 205 (ab) and an extraction electrode 207 (ab) connected to the excitation electrode 205 (ab), and a surface facing the crystal piece 203. And a lid body 202 (ab) having a through hole 206 (ab) penetrating through the recess 204 (ab), and the crystal piece 203 is directly bonded by a siloxane bond to the lid body 202. In the three-layer All Quartz Package stacked in a manner sandwiched between (ab), the through-hole 206 (ab) is sealed, and the mounting electrodes 209 (ab) connected to the conductive bonding material 208 by, for example, vapor deposition are disposed on both ends. It is disclosed to form on the side surface and both main surfaces.

  FIG. 13 shows a piezoelectric vibrator according to the second prior art. FIG. 13A is a general view, and FIG. 13B is a diagram showing a process of forming the external terminal of FIG. 13A. As shown in FIG. 13, Patent Document 2 discloses a three-layer All Quartz Package in which a base sheet-like wafer 303, a crystal wafer 305, and a lid sheet-like wafer 301 are laminated in this order from the bottom. The metal powder 308 is sprayed on the through-holes 302 formed in advance on the base sheet-like wafer 303 of the formed crystal resonator 306, and the metal powder 308 is deposited therein, while the surface of the crystal resonator element 304 and the through-holes are deposited. In addition to filling the gap with 302, metal powder 308 is deposited inside the through hole 302, and reaches the surface of the base sheet-like wafer 303 through the inside of the through hole 302 from the crystal resonator element 304 inside the crystal resonator 306. It is disclosed that the electrical conduction path 307 is formed by packing up and down. When the metal powder 308 is sprayed on the through hole 302, the metal powder 308 is melted by frictional heat generated by friction with the inner wall of the through hole 302, filling the gap between the surface of the crystal resonator element 304 and the through hole 302. Then, the metal powder 308 is closely attached and deposited inside the through-hole 302, and is packed and adhered from the crystal resonator element 304 inside the crystal resonator 306 to the surface of the base sheet-like wafer 303 through the inside of the through-hole 302. .

  As the metal powder 308, powdery aluminum (Al), copper (Cu), silver (Ag), gold (Au), etc. having a particle size of about 10 μm can be used, and the size of the through hole 302 is the diameter. However, it is disclosed that the external terminal shape is not substantially rectangular, and the through hole 302 as shown in FIG. Yes.

  FIG. 14 shows a piezoelectric vibrator according to the third prior art. FIG. 14A is an overall view, and FIG. 14B is a diagram showing a process of forming the external terminal of FIG. As shown in FIG. 14, Patent Document 3 also discloses a metal foil fine particle in a three-layer All Quartz Package in which base sheet-like wafer 403, crystal wafer 405, and lid sheet-like wafer 401 are laminated in this order from below. The metal foil 409 disposed between the through holes 402 of the base sheet-like wafer 403 of the crystal resonator 406 in which the 411 is formed in a wafer shape is irradiated with the laser light 410 emitted from the laser irradiation device 408 and melted. The metal foil fine particles 411 are deposited in the previous through-holes 402 to deposit the metal foil fine particles 411 inside the through-holes 402, and the gap between the surface of the quartz crystal vibrating element 404 and the through-holes 402 is filled with the metal fine particles 411. It is deposited inside the through hole 402, and passes through the inside of the through hole 402 from the crystal vibrating element 404 inside the crystal resonator 406. An electrical conduction path forming method is disclosed in which metal fine particles 411 are deposited up to the surface of the base sheet-like wafer 403 to form an electrical conduction path 407.

JP 2000-269775 A JP 2008-113378 A JP 2008-167302 A

However, in the prior art documents 1 to 3, there is originally a gap (gap) between the opening surface of the through hole and the routing electrode. In the prior art document 1, the wax material (or dissolved metal fine particles) due to the surface tension. Is pulled toward the inner wall surface of the through-hole with a large contact area, so that the wax material does not reach the electrode, and as a result, there is a risk that the electrical connection between the wax material in the through-hole and the routing electrode may not be secured. was there.
Further, in the prior art document 2 and the prior art document 3, the metal powder or metal foil fine particles are deposited while being dissolved in the through-holes, but the heat capacity of the metal powder or metal foil fine particles previously deposited and the irradiated metal The difference in heat capacity between the powder or metal foil fine particles gradually increases, the dissolution quality (swelling property) of the irradiated metal powder or metal foil fine particles gradually decreases, the resistance increases, and the connection reliability decreases. There was a problem of fear.

  Therefore, the present invention pays attention to the above problem, and an electronic component having a structure in which connection reliability is improved in electrical connection via a through electrode between an extraction electrode of the intermediate layer and an external electrode formed on the base substrate, And a piezoelectric vibrator.

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 application examples.
Application Example 1 An electronic component formed by mounting an electronic element piece on a base substrate, the base substrate including a through hole formed at a position facing the electronic element piece, and the through hole A sealing member for sealing, and the electronic element piece has a convex portion on a main surface facing the through hole of the electronic element piece, and a conductive film formed on a surface of the convex portion. An electronic component characterized by passing through an opening surface of the through hole facing the electronic element piece.

  With the above configuration, the conductive film formed on the convex portion can enter the through hole. Therefore, the electronic component can be easily connected between the through electrode formed in the through hole and the conductive film.

Application Example 2 The electronic component according to claim 1, wherein the convex portion penetrates the opening surface.
Thereby, since a convex part will be engage | inserted by a through-hole, alignment at the time of lamination | stacking with an electronic element piece and a base substrate becomes easy, and it can improve working efficiency.

Application Example 3 A piezoelectric vibrator formed by mounting a piezoelectric vibrating piece having an excitation electrode on a base substrate, the base substrate having a through hole formed at a position facing the piezoelectric vibrating piece The piezoelectric vibrating piece is formed on the main surface of the piezoelectric vibrating piece facing the through hole and on the surface of the protruding portion. A conductive film electrically connected to the excitation electrode, and the conductive film formed on the surface of the convex portion passes through the opening surface of the through hole facing the piezoelectric vibrating piece. A piezoelectric vibrator characterized by comprising:

  With the above configuration, the conductive film formed on the convex portion can enter the through hole. Accordingly, the piezoelectric vibrator can be easily connected between the through electrode formed in the through hole and the conductive film.

Application Example 4 A piezoelectric vibrator formed by laminating a piezoelectric vibrating piece layer on a base substrate, wherein the base substrate includes a through hole formed at a position facing the convex portion, and the through hole The piezoelectric vibrating piece layer includes a piezoelectric vibrating piece having an excitation electrode, a support frame that supports the piezoelectric vibrating piece and is bonded to the base substrate, and the piezoelectric vibration. A lead portion connected to the strip; a convex portion formed on a surface of the lead portion facing the base substrate; and a conductive member formed on the surface of the convex portion and electrically connected to the excitation electrode. And a conductive film formed on the surface of the convex portion passes through the opening surface of the through hole facing the piezoelectric vibrating piece.

  Even in a piezoelectric vibrator having a laminated structure, a piezoelectric vibrating piece can be obtained by providing a protruding portion and a conductive film connected to the excitation electrode and covering the surface of the protruding portion on the piezoelectric vibrating piece layer including the piezoelectric vibrating piece. Can be easily connected to the base substrate, and the electrical connection between the conductive film formed in the convex portion and entering the through-hole and the through-electrode can be easily performed, so that the yield can be improved. .

Application Example 5 The piezoelectric vibrator according to Application Example 4, wherein the support frame is bonded to the base substrate by solid phase bonding. As a result, the support frame and the base substrate are firmly bonded without forming an adhesive layer, and variation in the relative position between the convex portion and the through hole is suppressed, so that the electrical connection between the conductive film and the through electrode can be prevented. It is possible to suppress variations in characteristics of the piezoelectric vibrator by suppressing variations.

Application Example 6 In the application example 4 or 4, the convex portion is formed to protrude toward the substrate side from the surface of the support frame facing the base substrate, and the convex portion penetrates the opening surface. 5. The piezoelectric vibrator according to 5.
Thereby, since a convex part will be engage | inserted by a through-hole, the alignment at the time of lamination | stacking with a piezoelectric vibrating reed layer and a board | substrate becomes easy, and it can improve working efficiency.

It is a schematic diagram of the piezoelectric vibrator according to the first embodiment. 1 is an exploded perspective view of a piezoelectric vibrator according to a first embodiment. It is a figure which shows the manufacturing process of the piezoelectric vibrator which concerns on 1st Embodiment. It is a figure which shows the manufacturing process of the piezoelectric vibrator which concerns on 1st Embodiment. It is a figure which shows the manufacturing process of the piezoelectric vibrator which concerns on 1st Embodiment. It is a schematic diagram of a piezoelectric vibrator according to a second embodiment. It is a figure which shows the manufacturing process of the piezoelectric vibrating reed layer which concerns on 2nd Embodiment. It is a schematic diagram of the force detection element which concerns on 3rd Embodiment. It is a disassembled perspective view of the force detection element which concerns on 3rd Embodiment. It is a disassembled perspective view of the force detection element which concerns on 3rd Embodiment. It is a schematic diagram of the modification of the force detection element which concerns on 3rd Embodiment. It is a schematic diagram of the piezoelectric vibrator according to the first prior art. It is a schematic diagram of the piezoelectric vibrator which concerns on a 2nd prior art. It is a schematic diagram of the piezoelectric vibrator according to the third prior art.

  Hereinafter, the present invention will be described in detail with reference to embodiments shown in the drawings. However, the components, types, combinations, shapes, relative arrangements, and the like described in this embodiment are merely illustrative examples and not intended to limit the scope of the present invention only unless otherwise specified. .

  FIG. 1 shows a piezoelectric vibrator which is a first embodiment of an electronic component according to the present invention, and FIG. 1 (b), FIG. 1 (b) is a plan view of the piezoelectric vibrating reed layer constituting the piezoelectric vibrator, FIG. 1 (c) is a bottom view of the piezoelectric vibrating reed layer, and FIG. 2 (a) is an exploded perspective view seen from the lid side. FIG. 2 and FIG. 2B are exploded perspective views seen from the base substrate side. In the drawings and the following description, an orthogonal coordinate system (X axis, Y axis, Z axis) is used.

  The piezoelectric vibrator according to the first embodiment is a piezoelectric vibrator formed by mounting a piezoelectric vibrating piece having an excitation electrode on a main surface of a base substrate, and the base substrate faces the piezoelectric vibrating piece. A through hole formed at a position where the through hole is formed, and a through electrode that seals the through hole. The piezoelectric vibrating piece includes a convex portion on a main surface of the piezoelectric vibrating piece facing the through hole, and the convex And a lead electrode formed on the surface of the convex portion and electrically connected to the excitation electrode, and the lead electrode formed on the surface of the convex portion faces the piezoelectric vibrating piece of the through hole It has the structure which has penetrated the opening surface of the side to do.

  More specifically, the piezoelectric vibrating piece is formed by laminating a piezoelectric vibrating piece layer on the main surface of the base substrate, the base substrate having a through hole formed at a position facing the convex portion, A through-electrode that seals the through-hole, and the piezoelectric vibrating piece layer includes a piezoelectric vibrating piece having an excitation electrode, a support frame that supports the piezoelectric vibrating piece and is bonded to the base substrate, A lead portion connected to the piezoelectric vibrating piece, a convex portion formed on a surface of the lead portion facing the base substrate, and formed on the surface of the convex portion and electrically connected to the excitation electrode And the conductive film formed on the surface of the convex part passes through the opening surface of the through hole facing the piezoelectric vibrating piece. The piezoelectric vibrator 10 is obtained by dividing the laminated structure of the base substrate, the piezoelectric vibrating piece layer, and the lid wafer into individual pieces.

  The piezoelectric vibrating reed layer 12 is formed of a piezoelectric substrate such as quartz, and includes the piezoelectric vibrating reed 14, a connecting portion (first connecting portion 16, second connecting portion 18), and a leading portion (first leading portion 20, second leading portion). 22), convex portions (first convex portion 36, second convex portion 38) and the support frame 24, and the outer shape of the piezoelectric vibrating reed layer 12 is a photolithographic technique and etching as shown in the manufacturing process described later. It can be formed using a combination of techniques.

  The piezoelectric vibrating piece 14 is formed as a tuning fork type vibrating piece, a thickness sliding vibrating piece, or the like, but in this embodiment, an inverted mesa type thickness sliding vibrating piece formed thinner than the support frame 24 is used. . The piezoelectric vibrating reed 14 is connected to the lead-out portions 20a and 20b provided at the two corners on the −X direction side in the support frame 24 at both ends of one end in the longitudinal direction (± X direction). Connected to the connecting portion 16 and the second connecting portion 18, the piezoelectric vibrating piece 14 is supported by the support frame 24 with one end in the longitudinal direction (one end in the −X direction) being cantilevered.

  Excitation electrodes (first excitation electrode 26 and second excitation electrode 28) are formed on both surfaces of the piezoelectric vibrating piece 14 by sputtering, and the first excitation electrode 26 facing the main surface of the lid 40 is similarly sputtered. The first extraction electrode 30 formed by the above is connected, and the second extraction electrode 32 is also connected to the second excitation electrode 28 facing the main surface of the base substrate 42 by sputtering or the like.

  In the piezoelectric vibrating reed layer 12, the lead portions 20 a and 20 b are formed at the two corners on the −X direction side in the support frame 24 as described above, and of the two corners on the + X direction side, A second lead portion 22 is formed on the diagonal line. The drawer portion 22 and the drawer portion 20 a are connected by an extending portion 34 connected to the support frame 24. Therefore, the lead portion 22 is connected to the piezoelectric vibrating piece 14 via the extending portion 34, the lead portion 20 b, and the second connecting portion 18. Hereinafter, the drawer portion 20a is referred to as a first drawer portion 20, and the drawer portion 20b is referred to as a second drawer portion 2.

  A first convex portion 36 is formed on the surface of the first lead portion 20 facing the base substrate 42 side, and similarly, a second convex portion 38 is formed on the main surface side of the base substrate 42 of the second lead portion 22. Has been.

  The first lead electrode 30 connected to the first excitation electrode 26 extends to the main surface side of the base substrate 42 in the first connecting portion 16 and faces the main surface of the base substrate 42 of the first lead portion 20. It is drawn out to the side and is formed so as to cover the surface of the first convex portion 36 formed in the first lead portion 20. On the other hand, the second lead electrode 32 connected to the second excitation electrode 28 extends to the side of the second connecting portion 18 and the extending portion 34 facing the main surface of the base substrate 42, and It is drawn out to the side facing the main surface of the base substrate 42 and is formed so as to cover the surface of the second convex portion 38 formed in the second lead portion 22.

  The base substrate 42 is a rectangular member made of a piezoelectric material such as quartz, and the peripheral portion thereof is joined to the support frame 24 of the piezoelectric vibrating reed layer 12. The base substrate 42 has a tapered through hole (first hole) in which the inner diameter gradually decreases from the second surface 42b, which is the other main surface opposite to the first surface 42a, toward the first surface 42a. 1 through hole 44 and second through hole 46) are formed, and each through hole faces the first convex portion 36 and the second convex portion 38 when the piezoelectric vibrating reed layer 12 is laminated on the base substrate 42. Formed in position. The through hole can be formed by etching or sand blasting before lamination, but when the through hole is formed in a tapered shape as described above, it is preferable to perform sand blasting. Sand blasting is performed by masking the ground surface while leaving a ground portion, and spraying grinding particles such as SiC having a diameter of about 20 μm onto the ground portion together with high-speed air. Moreover, it is preferable to perform etching treatment (light etching) on the inner wall of the through hole after the through hole is formed by sandblasting. Thereby, residual stress on the inner wall of the through hole is reduced to prevent adverse effects on the piezoelectric vibrator 10, and the inner wall of the through hole is smoothed to thereby described later metal films (first metal film 48, second metal). The film 50) can be easily formed.

  A metal film (first metal films 48 and 48a) is formed on the inner wall of the first through hole 44 and the first extraction electrode 30 formed on the first protrusion 36, respectively. Metal films (second metal films 50 and 50a) are formed on the second extraction electrodes 32 formed on the protrusions 38 by sputtering or the like. This metal film is formed by laminating the piezoelectric vibrating reed layer 12 on the base substrate 42, and then introducing metal particles constituting the metal film from the second surface 42b of the base substrate 42 by sputtering or the like to the inner wall and the convex portion of the through hole. It is formed by depositing on the formed extraction electrode. The first metal films 48 and 48a and the second metal films 50 and 50a are formed, and at the same time, the first external electrode 56 and the second metal film 50 connected to the first metal film 48 are formed on the second surface 42b of the base substrate 42. A second external electrode 58 to be connected can be formed. By forming these metal films, through-electrodes (first through-electrode 52 and second through-electrode 54) described later can be easily formed. Thus, the first metal film 48a (and the first extraction electrode 30) formed so as to cover the surface of the first convex portion 36 forms a conductive film that enters the first through hole 44, and the second convex portion 38 is formed. The second metal film 50a (and the second lead electrode 32) formed so as to cover the surface of the metal film forms a conductive film that enters the second through hole 46, and each of the through holes has openings on the side facing the piezoelectric vibrating piece 14. Will penetrate the surface.

  Then, through electrodes (first through electrode 52 and second through electrode 54) for vacuum-sealing the through hole are formed inside the through hole. Each through electrode is formed, for example, by dissolving and solidifying a solder ball 51 (see FIGS. 2 and 5) in the through hole, as shown in the manufacturing process described later. The first through electrode 52 is connected to the first metal film 48 formed on the inner wall of the first through hole 44 and the first metal film 48 a formed on the first extraction electrode 30. Therefore, the first lead electrode 30 is electrically connected to the first external electrode 56 through the first metal film 48 a, the first through electrode 52, and the first metal film 48. The second through electrode 54 is connected to the second metal film 50 formed on the inner wall of the second through hole 46 and the second metal film 50 a formed on the second lead electrode 32. Therefore, the second lead electrode 32 is electrically connected to the second external electrode 58 through the second metal film 50 a, the second through electrode 54, and the second metal film 50.

  Therefore, the excitation electrode (first excitation electrode 26, second excitation electrode 28) for exciting the piezoelectric vibrating piece 14 is driven via the external electrode (first external electrode 56, second external electrode 58). By connecting to a drive circuit (not shown), the piezoelectric vibrating piece 14 can be vibrated at a specific resonance frequency.

  By the way, in this embodiment, as shown in the partial enlarged view of FIG. 1A, the main surface of the first convex portion 36, the main surface of the second convex portion 38, and the main surface of the support frame 24 are the same plane. The first metal film 48a formed on at least the main surface of the first convex portion 36 penetrates the same plane, that is, penetrates the opening surface of the first through hole 44. The second metal film 50a that enters the inside of the first through hole 44 and is similarly formed on the main surface of the second convex portion 38 penetrates the same plane, that is, penetrates the opening surface of the second through hole 46. Thus, it enters the inside of the second through hole 46. On the other hand, a first metal film 48 is formed on the entire inner wall of the first through hole 44, and a second metal film 50 is formed on the entire inner wall of the second through hole 46. Since the first metal films 48 and 48a and the second metal films 50 and 50a have wettability with respect to the molten metal formed by melting the solder balls 51 (see FIG. 2B and FIG. 5), The first through electrode 52 is bonded to the first metal films 48 and 48a, and the second through electrode 54 is bonded to the second metal films 50 and 50a, and the entire first through hole 44 and the entire second through hole 46 are sealed. It can be formed to stop. Accordingly, it is possible to prevent a gap from being formed between the through electrode and the lead electrode (metal film), and to achieve a stable electrical connection between the lead electrode and the through electrode. A stable electrical connection can be achieved between the electrodes.

  The lid 40 is formed of a piezoelectric base substrate such as quartz, and its periphery is joined to the main surface of the support frame of the piezoelectric vibrating piece layer.

  The bonding between the base substrate 42 and the piezoelectric vibrating piece layer 12 and the bonding between the piezoelectric vibrating piece layer 12 and the lid 40 are preferably performed by solid phase bonding. Here, solid phase bonding refers to a method of bonding solid phases to each other without using an adhesive, and examples include direct bonding, metal bonding, and anodic bonding. In this embodiment, it is preferable to perform direct bonding. It is. Direct bonding to a quartz substrate includes a method of irradiating plasma to a bonding surface of a quartz substrate that is ensured to be flat, activating the bonding portion, and bringing the bonding surface into contact with each other. A new bonding film is not formed by bonding. In direct bonding, sufficient bonding strength is obtained with a bonding area far smaller than that of a wax material such as eutectic metal, and in this embodiment, the bonding width is about 50 μm to 200 μm and wafers can be bonded with sufficient bonding strength. .

  Further, by performing direct bonding, variations in relative position between wafers are suppressed. More specifically, since the variation in the relative position between the base substrate 42 and the support frame 24 is suppressed, the first protrusion 36 and the first through hole 44, and the second protrusion 38 and the second through hole 46 ± Variation in the relative position in the Z direction is suppressed. Therefore, there is no variation in the formation of the metal film, and further, there is no variation in the connection state of the first through electrode 52 and the second through electrode 54 that are formed thereafter, so that variation in the characteristics of the piezoelectric vibrator 10 is suppressed. be able to.

  By laminating the base substrate 42, the piezoelectric vibrating reed layer 12, and the lid 40 as the same material (piezoelectric material such as quartz crystal), the linear expansion coefficients of the layers coincide with each other. Generation of stress can be suppressed, and an error in the oscillation frequency of the piezoelectric vibrating piece 14 can be suppressed.

  3, 4 and 5 show the manufacturing process of the piezoelectric vibrator 10 according to the first embodiment. First, as shown in FIG. 3A, a rectangular base substrate 42 is prepared, and the first through hole 44 and the second through hole 46 are etched at positions facing the first convex portion 36 and the second convex portion 38, respectively. Alternatively, it is formed by sand blasting (FIG. 3B).

  Next, as shown in FIG. 4A, a crystal element plate 60 for the piezoelectric vibrating piece layer 12 is prepared, and the support frame 24, the first connecting portion 16 (not shown), and the second connecting portion are provided on the crystal element plate 60. 18 (not shown), the first lead portion 20, the second lead portion 22, the extending portion 34 (not shown in FIG. 4), the first convex portion 36, and the second convex portion 38, leaving the outer shape of the piezoelectric vibrating piece 14. Etching is performed from both sides until the thickness is reached (FIG. 4B), leaving the region etched to the outer shape of the support frame 24 and the thickness of the piezoelectric vibrating piece 14, and further, the first convex portion 36 and the second convex portion 38. Etching is performed until the first lead portion 20, the second lead portion 22, and the extending portion 34 have a predetermined thickness on the surface of the quartz substrate 60 facing the base substrate 42, leaving the outer shape (FIG. 4C). , Support frame 24, first connecting portion 16, second connecting portion 18, first drawer portion 20. By etching until the second lead portion 22, the extending portion 34 (not shown in FIG. 4), the first convex portion 36, the second convex portion 38, and the piezoelectric vibrating piece 14 pass through the quartz crystal substrate 60, The outer shape of the piezoelectric vibrating reed layer 12 is formed (FIG. 4D). Then, the first excitation electrode 26, the second excitation electrode 28, the first extraction electrode 30, and the second extraction electrode 32 are formed at predetermined positions (FIG. 4E).

  In this state, since the piezoelectric vibrating piece 14 can oscillate at a specific oscillation frequency, a driving circuit (not shown) is connected to the first extraction electrode 30 and the second extraction electrode 32 to drive the piezoelectric vibrating piece 14. As shown in FIG. 4 (f), the frequency is adjusted by thickening a part of the first excitation electrode 26 by vapor deposition or thinning it by dry etching using argon plasma irradiation.

Next, the following steps are performed in a vacuum chamber (not shown). As shown in FIG. 5A, the base substrate 42, the piezoelectric vibrating reed layer 12, and the lid 40 are laminated.
That is, the peripheral edge of the base substrate 42 and the support frame 24 of the piezoelectric vibrating piece layer 12 are bonded by solid phase bonding (direct bonding), and similarly, the support frame 24 and the lid 40 are bonded by solid phase bonding (direct bonding). .

  Next, as shown in FIG. 5B, first metal films 48 and 48a are formed in the first through hole 44 by sputtering or the like, and second metal films 50 and 50a are formed in the second through hole 46 (partial). Further, a first external electrode 56 is formed around the first through hole 44 of the second surface 42b of the base substrate 42, and a second external electrode 58 is similarly formed around the second through hole 46. .

  Then, as shown in FIG. 5C, the solder ball 51 is inserted into the first through hole 44 and the second through hole 46, and the gas generated and staying in the internal space 10a of the piezoelectric vibrating piece 14 is transferred to the first through hole. 44 and the second through hole 46, the solder ball 51 is irradiated with a laser beam (not shown) to melt and solidify the solder ball 51, whereby the first through hole is formed as shown in FIG. The piezoelectric element 10 is formed by forming the first through electrode 52 for sealing 44 and the second through electrode 54 for sealing the second through hole 46. Thereby, an internal space 10a is formed inside the piezoelectric vibrator 10, and the piezoelectric vibrating piece 14 is vacuum-sealed in the internal space 10a.

  A piezoelectric vibrator according to the second embodiment is shown in FIG. 6A is a side sectional view (with a partially enlarged view) viewed from the side direction, FIG. 6B is a plan view of a piezoelectric vibrating piece constituting the piezoelectric vibrator, and FIG. 6C is a piezoelectric vibrating piece layer. FIG. The piezoelectric vibrator 70 according to the second embodiment is basically similar in configuration to the piezoelectric vibrator 10 of the first embodiment. However, in the piezoelectric vibrating piece layer 72, the convex portions (the first convex portion and the second convex portion). ) Protrudes toward the base substrate from the surface of the support frame facing the base substrate, so that the convex portion penetrates the opening surface of the through-hole when stacked.

  Thus, by forming the 1st convex part and the 2nd convex part, each convex part enters a penetration hole (the 1st penetration hole, the 2nd penetration hole), and each convex part and a penetration hole interfere in plane. Therefore, the alignment property at the time of laminating the piezoelectric vibrating reed layer on the base substrate is improved, and displacement at the time of lamination can be prevented. In addition, the contact area of the through electrode in the convex portion and the area of the inner wall of the through hole are balanced, and the surface tension of the molten metal formed by melting the solder balls is made uniform. Connection reliability is improved. Further, the junction area between the first lead electrode (and the first metal film) formed on the first convex portion and the first through electrode, the second lead electrode (and the second metal film) formed on the second convex portion, and Since the junction area with the second through electrode increases, the reliability of the electrical connection between the extraction electrode and the through electrode is further improved as compared with the case of the first embodiment.

FIG. 7 shows a manufacturing process of the piezoelectric vibrating piece layer constituting the piezoelectric vibrator of the second embodiment.
First, as shown in FIG. 7A, a crystal element plate 100 for the piezoelectric vibrating reed layer 12 is prepared, and a first connecting portion 76 (see FIG. 6) and a second connecting portion 78 (see FIG. 6) are provided on the crystal element plate 100. 6), etching is performed from both sides until the thickness of the piezoelectric vibrating piece 74 is reached, leaving the outer shapes of the first lead portion 80, the second lead portion 82, the support frame 84, and the extending portion 86 (FIG. 7B), On the base substrate 42 of the first lead portion 80, the second lead portion 82, and the extending portion 84, leaving the regions etched up to the outer shape of the first convex portion 88, the outer shape of the second convex portion 90, and the thickness of the piezoelectric vibrating piece 74. The quartz substrate 100 is etched from the facing surface to the thickness of the support frame 84 (FIG. 7C), the outer shape of the support frame 84, the outer shape of the first convex portion 88, the outer shape of the second convex portion 90, and the piezoelectricity. The base substrate leaving the outer shape of the region etched to the thickness of the vibrating piece 14 2, the first connecting portion 76, the second connecting portion 78, the first drawing portion 80, the second drawing portion 82, and the extending portion 86 (etching is performed on the crystal substrate 100 until the thickness is not shown in FIG. 7. (FIG. 7D), the support frame 84, the first convex portion 88, the second convex portion 90, the first connecting portion 76, the second connecting portion 78, the first leading portion 88, the second leading portion 90, and the piezoelectric. The outer shape of the piezoelectric vibrating piece layer 74 is formed by etching until the quartz crystal substrate 100 is penetrated while leaving the outer shape of the vibrating piece 74 (FIG. 7E), and the first excitation electrode 92 and the second excitation electrode 94. Then, the first lead-out electricity 96 and the second lead-out electrode 98 are formed at predetermined positions (FIG. 7F).

  In this state, the piezoelectric vibrating piece can oscillate at a specific oscillation frequency. Therefore, a driving circuit (not shown) is connected to the first extraction electrode 96 and the second extraction electrode 98 to drive the piezoelectric vibrating piece 74, and FIG. As shown in (g), the frequency is adjusted by thickening part of the first excitation electrode 92 by vapor deposition or thinning by dry etching using argon plasma irradiation. Since the lamination of the base substrate 42, the piezoelectric vibrating reed layer 72, and the lid 40 is the same as that in the first embodiment (see FIG. 5), the description is omitted.

  The first metal films 48 and 48a and the second metal films 50 and 50a have been described as being formed after the piezoelectric vibrating reed layer is laminated on the base substrate. However, before the lamination, the first through holes 44 and the second through holes are formed. The first metal film 48 and the second metal film 50 may be formed only on the inner wall of the hole 46, respectively.

8, 9, and 10 are force detection elements that are the third embodiment of the electronic component according to the present invention, and FIG. 8A is a side cross-sectional view of the force detection element as viewed from the side. FIG. 8B is a partial detail view of FIG. 8A, FIG. 8C is a bottom view of the pressure-sensitive element piece constituting the force detection element, FIG. 9 is an exploded perspective view seen from the base substrate side, and FIG. The exploded perspective view seen from the side is shown.
For example, a piezoelectric vibrator mounted on a diaphragm having a flexible portion that bends by receiving a force directly, for example, by receiving a pressure to be measured via a support portion, has an electrode pattern on a plate-like piezoelectric substrate, for example. Formed, the detection axis is set in the direction of detecting the force, and when the pressure to be measured is received by the pressure receiving portion of the diaphragm from the direction orthogonal to the direction of the detection axis, the flexible portion bends, and via the support portion When a force is applied to the piezoelectric vibrator, a tensile stress is generated in the direction of the detection axis, so that the resonance frequency of the piezoelectric vibrator changes, and the pressure value of the pressure to be measured is determined from the change in the resonance frequency. To detect. It has a pressure sensor, a diaphragm as a pressure receiving means, and a pressure sensitive element (double tuning fork vibrator) mounted on a support portion formed on the diaphragm, and the pressure receiving surface of the diaphragm faces the outer surface while accommodating these in a container. Thus, the structure is vacuum-sealed.

  A force detection element 700 according to the third embodiment includes an excitation electrode 701 formed on two columnar beams of a double tuning fork vibrator 705 as a pressure sensitive element, and an extraction electrode (first extraction) connected to the excitation electrode 701. A double tuning fork vibrator having a pressure sensitive element 772 having an electrode 702 and a second lead electrode 703) mounted on a support portion 706 formed on an inner main surface 704 b opposite to the pressure receiving surface 704 a of the diaphragm 704. 705, and the double tuning fork vibrator 705 is formed on a convex portion (first convex portion 736, second convex portion 738) formed on a main surface facing the base substrate 742, and on the surface of the convex portion. The base substrate 742 has through holes (first through holes 744) formed at positions facing the protrusions. The base electrode 742 has a lead electrode (first lead electrode 702, second lead electrode 703) formed. 2nd through-hole 746) and through-electrodes (first through-electrode 752 and second through-electrode 754) that seal the through-hole, and includes a base substrate 742, a pressure-sensitive element piece layer 772, and a diaphragm 704. Thus, a three-layer structure having an internal space 700a is formed.

The diaphragm 704 has a flexible portion 704c and a thick portion 704d surrounding the outer edge of the flexible portion 704c.
The pressure-sensitive element piece 772 includes a double tuning fork vibrator 705 composed of a vibrating portion 705a composed of two columnar beams and base portions 705b located at both ends of the vibrating portion 705a, and a rectangle surrounding the double tuning fork vibrator 705. Support frame portion 773, and a beam 707 connecting the support frame portion 773 and the base portion 705b. The main surface of the support frame portion 773 that faces the base substrate 742 includes an outer frame 773a and an inner frame 773b that is formed on the inner side of the outer frame and is thinner than the outer frame. 707 is connected. Further, a first convex portion 736 is formed at a position of the inner frame 773b facing a first through hole 744 described later, and a second convex portion 738 is formed at a position facing the second through hole 746 described later. A first extraction electrode 702 and a second extraction electrode 703 connected to the excitation electrode 701 are formed on the inner frame 773b. In FIG. 12, the excitation electrode 701 is depicted as being formed only on the base substrate 742 side, but it is assumed that it is actually formed on both sides.

As in the first embodiment, the thick portion 704d of the diaphragm 704 and the outer edge portion 742c of the base substrate 742 are directly bonded to both surfaces of the outer frame 773a of the support frame 773 of the pressure-sensitive element layer 712, respectively. Are joined. Similarly, the pair of base portions 705b are joined to the pair of support portions 706 using direct joining (see FIG. 8A).
On the other hand, as in the first embodiment, the through-hole (first through-hole 744) has a tapered shape that gradually decreases the inner diameter from the second surface 742b opposite to the first surface 742a of the base substrate 742 toward the first surface 742a. , A second through hole 746) is formed.

  Metal films (first metal films 748 and 748a) are respectively formed on the inner wall of the first through hole 744 and the first extraction electrode 730 formed on the first protrusion 736, and the inner wall of the second through hole 746 and Metal films (second metal films 750 and 750a) are formed on the second extraction electrodes 732 formed on the second protrusions 738 by sputtering or the like. The first metal films 748 and 748a and the second metal films 750 and 750a are formed, and at the same time, the first external electrode 756 and the second metal film 750 connected to the first metal film 748 are formed on the second surface 742b of the base substrate 742. A second external electrode 758 to be connected can be formed. As in the first embodiment, through electrodes (first through electrode 752 and second through electrode 754) that seal the through hole are formed inside the through hole. The first through electrode 752 is connected to the first metal film 748 formed on the inner wall of the first through hole 744 and the first metal film 748a formed on the first extraction electrode 730 (see FIG. 8B). . Therefore, the first lead electrode 730 is electrically connected to the first external electrode 756 via the first metal film 748 a, the first through electrode 752, and the first metal film 748. The second through electrode 754 is connected to the second metal film 750 formed on the inner wall of the second through hole 746 and the second metal film 750a formed on the second lead electrode 732 (see FIG. 8B). ). Therefore, the second lead electrode 732 is electrically connected to the second external electrode 758 via the second metal film 750a, the second through electrode 754, and the second metal film 750.

  Therefore, the excitation electrode 701 for exciting the double tuning fork vibrator 705 is connected to a drive circuit (not shown) for driving the double tuning fork vibrator 705 via the external electrodes (first external electrode 756 and second external electrode 758). Thus, the double tuning fork vibrator 705 can be vibrated at a specific resonance frequency. By the way, when the diaphragm 704 is bent by pressure, the pair of support portions 706 are separated from each other, and the pair of base portions 705b connected thereto are also separated from each other, so that the resonance frequency of the double tuning fork vibrator 705 varies. . Therefore, the pressure value in the pressure measurement region received by the diaphragm 704 can be obtained by using the fluctuation of the resonance frequency. Note that the manufacturing method of the pressure-sensitive element layer 772 is the same as that of the piezoelectric vibrating reed layer 12 in the first embodiment, and a description thereof will be omitted. Further, as in the second embodiment, the first convex portion 736 and the second convex portion 738 can be formed to protrude from the outer frame 773a of the support frame 773 toward the base substrate 742.

  As described above, the embodiment has been described on the assumption of the piezoelectric vibrator and the force detection element, but is not limited thereto. That is, in an electronic component having a laminated structure, the electronic component is formed by mounting an electronic element piece constituting an electronic component and having an electrode on a base substrate, and the base substrate is located at a position facing the electronic element piece. And the electronic element piece has a convex portion on a main surface thereof opposed to the through hole of the electronic element piece, and the electronic element piece By forming the conductive film formed on the surface of the convex portion through the opening surface of the through hole facing the electronic element piece, the electrode of the electronic element piece and the electrode on the substrate side Electrical connection can be realized with high reliability.

  Further, as shown in FIGS. 1 (a), 6 (a), and 8 (b), in any of the embodiments, a gap 10b is formed between the surface of the extraction electrode at the vibrating piece corner and the opening surface of the through hole. , 70b, 700b, and when forming a through electrode with solder balls, the gas in the internal space is discharged to the outside through the gaps 10b, 70b, 700b, and the internal space is evacuated before forming the through electrode. To do. The through electrode has a function of electrically connecting the electrode film (extraction electrode, metal film) on the surface of the convex portion and the external electrode. Since the gaps 10b, 70b, and 700b have a function of evacuating the internal space, the through hole is hermetically sealed with a solder material such as a solder ball in order to electrically connect the extraction electrode and the external electrode. In the conventional structure, since there is a gap between the opening surface of the through hole and the extraction electrode, there was a problem in the reliability of hermetic sealing and reliability in ensuring electrical conduction. In any of the embodiments, since the convex portion is provided at the portion facing the through hole of the piezoelectric vibrating piece and the extraction electrode is formed on the surface of the convex portion, the convex surface of the extraction electrode penetrates the opening surface of the through hole. Since the penetration electrode penetrates into the through hole, the penetration electrode formed by melting the solder ball can securely connect the extraction electrode and the external electrode and hermetically seal the penetration hole. certainly It can be emptied.

  FIG. 11 shows a modification of the force detection element of the third embodiment. In FIG. 11, the detailed view of the area surrounded by the broken line is the same as that on the right side of FIG. In the present embodiment, since only one part may be vacuum-sealed, as in the modification shown in FIG. 11, any one of the through holes has the same surface of the vibrating piece and the opening surface of the through hole. It is sufficient that the other through-hole has the above-described structure. Such a structure can be similarly applied to the first and second embodiments. That is, in the electronic component according to the present invention, at least one of the plurality of through electrodes has gaps 10b, 70b, and 700b between the surface of the lead portion of the vibrating piece corner and the opening surface of the through hole, When the through electrode is formed with a ball, the internal space gas is discharged to the outside through the gaps 10b, 70b, and 700b to evacuate the internal space, and then the through electrode is formed. Pulling can be performed only at the one location.

DESCRIPTION OF SYMBOLS 10 ......... Piezoelectric vibrator, 12 ......... Piezoelectric vibrating piece layer, 14 ......... Piezoelectric vibrating piece, 16 ......... First connecting portion, 18 ......... Second connecting portion, 20 ......... First drawer , 22... Second extraction part, 24... Support frame, 26... First excitation electrode, 28... Second excitation electrode, 30. 2 lead electrode 34... Extension portion 36... First protrusion 38... Second protrusion 40... Lid 42... Substrate 44. 46 ......... Second through hole, 48 ......... First metal film, 48a ......... First metal film, 50 ......... Second metal film, 50a ......... Second metal film, 51 ......... Solder Ball 52... First through electrode 54 54 Second through electrode 56 First external electrode 58 Second external electrode 60 Quartz substrate 70 Piezoelectric Rotating element 72... Piezoelectric vibrating piece layer 74... Piezoelectric vibrating piece 76... First connecting portion 78... Second connecting portion 80. ... second lead part, 84 ......... support frame, 86 ......... extension part, 88 ......... first convex part, 90 ...... second convex part, 92 ......... first excitation electrode, 94 ... ... Second excitation electrode, 96 ......... First extraction electrode, 98 ......... Second extraction electrode, 100 ......... Quartz substrate, 202 (ab) ......... Cover body, 203 ......... Crystal piece, 204 ( ab) ......... concave, 205 (ab) ... excitation electrode, 206 (ab) ... through-hole, 207 (ab) ... extraction electrode, 208 ... conductive adhesive, 209 (ab) ……… Mounting electrode, 301 ……… Sheet wafer for lid, 302 ……… Through hole, 303 ……… Sheet wafer for base, 30 ............ Quartz vibrating element, 305... Quartz wafer, 306... Quartz crystal oscillator, 307... Electrical conduction path, 308. …… Through hole, 403... Base sheet wafer, 404... Quartz vibrating element, 405... Quartz wafer, 406... Quartz vibrator, 407. Laser irradiation device, 409... Metal foil, 410... Laser light, 411... Metal foil fine particle, 700... Force detection element, 701... Excitation electrode, 702. 703 ......... Second extraction electrode, 704 ......... Diaphragm, 705 ......... Double tuning fork vibrator, 706 ......... Supporting part, 707 ......... Beam, 736 ......... First convex part, 738 ......... Second convex part, 742... Base substrate, 74 4 ......... first through hole, 746 ......... second through hole, 748 ......... first metal film, 750 ......... second metal film, 752 ......... first through electrode, 754 ......... first Two through electrodes, 756... First external electrode, 758... Second external electrode, 772... Pressure-sensitive element layer, 773.

Claims (6)

An electronic component formed by mounting an electronic element piece on a base substrate,
The base substrate has a through hole formed at a position facing the electronic element piece, and a sealing member for sealing the through hole,
The electronic element piece has a convex portion on a main surface facing the through hole of the electronic element piece, and a conductive film formed on a surface of the convex portion faces the electronic element piece of the through hole. An electronic component characterized by penetrating through the opening on the side.   The electronic component according to claim 1, wherein the convex portion penetrates the opening surface. A piezoelectric vibrator formed by mounting a piezoelectric vibrating piece having an excitation electrode on a base substrate,
The base substrate has a through hole formed at a position facing the piezoelectric vibrating piece, and a through electrode that seals the through hole,
The piezoelectric vibrating piece includes a convex portion on a main surface of the piezoelectric vibrating piece facing the through hole, and a conductive film formed on the surface of the convex portion and electrically connected to the excitation electrode. Have
The piezoelectric vibrator, wherein the conductive film formed on the surface of the convex part passes through the opening surface of the through hole facing the piezoelectric vibrating piece. A piezoelectric vibrating piece formed by laminating a piezoelectric vibrating piece layer on a base substrate,
The base substrate is
A through-hole formed at a position facing the convex portion;
A through electrode for sealing the through hole,
The piezoelectric vibrating reed layer is
A piezoelectric vibrating piece having an excitation electrode;
A support frame that supports the piezoelectric vibrating piece and is bonded to the base substrate;
A drawer connected to the piezoelectric vibrating piece;
A convex portion formed on a surface of the drawer portion facing the base substrate;
A conductive film formed on the surface of the convex portion and electrically connected to the excitation electrode;
The piezoelectric vibrator, wherein the conductive film formed on the surface of the convex part passes through the opening surface of the through hole facing the piezoelectric vibrating piece.   The piezoelectric vibrator according to claim 4, wherein the support frame is bonded to the base substrate by solid phase bonding.   6. The piezoelectric device according to claim 4, wherein the convex portion is formed to project from the surface of the support frame facing the base substrate toward the substrate, and the convex portion penetrates the opening surface. Vibrator.

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