Piezoelectric vibration device and manufacturing method thereof

Abstract

In the present invention, since the first and second mounting terminals connected to the first and second mounting terminal metal films formed on the two end portions of the piezoelectric vibration plate sandwiching the vibration portion are formed on the outer surface of the film bonded to the piezoelectric vibration plate, even if the size of the first and second mounting terminal metal films on both sides of the vibration portion is reduced in order to enlarge the vibration portion, the bonding area for mounting the first and second mounting terminals to be formed on the outer surface of the resin film can be ensured.

Description

Technical Field

[0001] The present invention relates to a piezoelectric vibration device such as a piezoelectric vibrator and a manufacturing method thereof. Background Art

[0002] Surface-mounted crystal oscillators are widely used as piezoelectric resonator devices, such as piezoelectric vibrators. For example, as described in Patent Document 1, these surface-mounted crystal oscillators utilize electrodes extending from excitation electrodes on both sides of a crystal resonator plate to holding electrodes within a box-shaped base made of ceramic with an open top surface, using a conductive adhesive. The crystal resonator plate is then mounted on the base. A lid is bonded to the opening of the base, where the crystal resonator plate is mounted, creating an airtight seal. Furthermore, mounting terminals for surface-mounting the crystal resonator are formed on the outer bottom surface of the base.

[0003] Patent Document 1: Japanese Patent Application Laid-Open No. 2005-184325

[0004] As described above, most piezoelectric vibrators are packaged in a ceramic base with a metal or glass lid bonded to the base. This makes the package expensive, and the piezoelectric vibrator expensive.

[0005] In addition, it is desired that the vibration characteristics of the piezoelectric vibrator be improved without increasing the size. Summary of the Invention

[0006] The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to provide a piezoelectric vibration device that is inexpensive and has improved vibration characteristics without increasing the size.

[0007] In order to achieve the above-mentioned object, the present invention is constructed as follows.

[0008] (1) A piezoelectric vibration device according to the present invention comprises: a piezoelectric vibration plate having a vibration portion including first and second excitation electrodes and first and second mounting terminal metal films connected to the first and second excitation electrodes, respectively; and first and second sealing members bonded to the two main surfaces of the piezoelectric vibration plate so as to cover the first and second excitation electrodes formed on the two main surfaces of the piezoelectric vibration plate, respectively; at least one of the first and second sealing members is a resin film; the first mounting terminal metal film is formed at one end portion of the piezoelectric vibration plate sandwiching the vibration portion; the second mounting terminal metal film is formed at the other end portion of the two ends; both ends of the film are bonded to the two end portions of the piezoelectric vibration plate sandwiching the vibration portion; a first mounting terminal connected to the first mounting terminal metal film is formed so as to cover the outer surface of one of the two ends of the film; and a second mounting terminal connected to the second mounting terminal metal film is formed so as to cover the outer surface of the other end portion of the film.

[0009] According to the piezoelectric vibration device involved in the present invention, since the first and second mounting terminal metal films respectively connected to the first and second excitation electrodes of the vibration part are respectively formed on the two end parts of the piezoelectric vibration plate sandwiching the vibration part, and the first and second mounting terminals respectively connected to the first and second mounting terminal metal films are formed in a manner covering the outer surface of the resin film constituting at least one of the first and second sealing parts joined to the piezoelectric vibration plate, even if the size of the first and second mounting terminal metal films sandwiching the vibration part is reduced in order to enlarge the vibration part, the size of the first and second mounting terminals formed on the outer surface of the film joined to the piezoelectric vibration plate can be made into the size required for mounting.

[0010] Thus, without increasing the size of the piezoelectric vibration device, the vibration portion can be enlarged to improve vibration characteristics, and the bonding area of ​​the first and second mounting terminals required for mounting the piezoelectric vibration device can be ensured.

[0011] In addition, since the piezoelectric vibration device has first and second mounting terminals connected to the first and second excitation electrodes respectively on the outer surface of the resin film bonded to the piezoelectric vibration plate, there is no need to accommodate the piezoelectric vibration plate in a box-shaped base with mounting terminals and an open top surface as in the past, and an expensive base is not required.

[0012] Furthermore, since a resin film is bonded to at least one of the two main surfaces of the piezoelectric vibration plate to seal at least one of the first and second excitation electrodes, costs can be reduced compared to a structure sealed with a metal, ceramic, or glass cover.

[0013] (2) In a preferred embodiment of the present invention, the first and second sealing components are the first and second films made of the resin, and both ends of the first and second films are respectively joined to the two end portions of the piezoelectric vibration plate that clamp the vibration portion, and a first mounting terminal connected to the metal film for the first mounting terminal is formed in a manner that covers the outer surface of one of the two ends of the first and second films, and a second mounting terminal connected to the metal film for the second mounting terminal is formed in a manner that covers the outer surface of the other of the two ends of the first and second films.

[0014] According to this embodiment, since the first mounting terminal is formed in a manner that covers the outer surface of one of the two end portions of the first and second films respectively bonded to the two main surfaces of the piezoelectric vibration plate, and the second mounting terminal is formed in a manner that covers the outer surface of the other of the two end portions of the first and second films, that is, the first and second mounting terminals are respectively formed at both ends of the film on the side of either main surface of the two main surfaces of the piezoelectric vibration plate, when the piezoelectric vibration device is mounted on a circuit substrate, etc., it can be mounted on either main surface.

[0015] Furthermore, since the first and second thin films made of resin are bonded to both main surfaces of the piezoelectric vibration plate and sealed so as to cover the first and second excitation electrodes, a metal, ceramic, or glass cover for sealing is unnecessary, further reducing costs.

[0016] (3) In one embodiment of the present invention, the first mounting terminal is formed in a manner that covers the entire outer surface of one end portion of the first and second films and the outer surface of one of the two end portions of the piezoelectric vibration plate that clamps the vibration portion, and the second mounting terminal is formed in a manner that covers the entire outer surface of the other end portion of the first and second films and the outer surface of the other of the two end portions of the piezoelectric vibration plate that clamps the vibration portion.

[0017] According to this embodiment, the first and second mounting terminals are formed so as to cover the entire outer surfaces of the first and second thin films and the ends of the piezoelectric diaphragm. Therefore, for example, by dipping the ends of the piezoelectric diaphragm to which the first and second thin films are bonded into a conductive paste and then thermally curing it, the first and second mounting terminals can be formed so as to cover the entire outer surfaces of the ends of the piezoelectric diaphragm to which the first and second thin films are bonded. This can reduce manufacturing costs compared to forming the first and second mounting terminals by sputtering or vapor deposition, for example.

[0018] (4) In another embodiment of the present invention, the piezoelectric vibration plate has an outer frame portion connected to the vibration portion by a connecting portion, the outer frame portion surrounds the outer periphery of the vibration portion which is thinner than the outer frame portion at a distance, the first and second mounting terminals are respectively formed on the outer frame portion with metal films, and the first and second films are respectively bonded to the outer frame portion to seal the first and second excitation electrodes of the vibration portion.

[0019] According to this embodiment, by bonding the peripheral ends of the first and second films to the outer frame surrounding the outer periphery of the vibrating portion, the first and second films do not come into contact with the vibrating portion thinner than the outer frame, thereby sealing the vibrating portion.

[0020] (5) In one embodiment of the present invention, the first and second mounting terminal metal films are formed across the two main surfaces and end surfaces of the outer frame portion, and the first and second thin films are bonded to the first and second mounting terminal metal films formed on the two main surfaces of the outer frame portion.

[0021] According to this embodiment, since the first and second mounting terminal metal films are formed not only on the two main surfaces of the outer frame portion of the piezoelectric diaphragm to which the first and second thin films are bonded, but also on the end surfaces of the outer frame portion, the first and second mounting terminal metal films on these end surfaces can be electrically connected to the first and second mounting terminals, respectively. Furthermore, since the first and second thin films are bonded to the first and second mounting terminal metal films formed on the two main surfaces of the outer frame portion, a more secure bond is achieved compared to bonding the first and second thin films to the outer frame portion of the piezoelectric substrate itself that constitutes the piezoelectric diaphragm.

[0022] (6) In another embodiment of the present invention, a first sealing pattern is formed on one of the two main surfaces of the outer frame portion, the first sealing pattern is connected to the metal film for the first mounting terminal, surrounds the vibration portion together with the metal film for the first mounting terminal, and is bonded to the first film, and a second sealing pattern is formed on the other of the two main surfaces of the outer frame portion, the second sealing pattern is connected to the metal film for the second mounting terminal, surrounds the vibration portion together with the metal film for the second mounting terminal, and is bonded to the second film.

[0023] According to this embodiment, since the first and second sealing patterns on the two main surfaces of the outer frame portion to which the first and second films are bonded are formed in a manner that respectively surrounds the vibration portion together with the first and second mounting terminal metal films, the peripheral end portions of the first and second films can be firmly bonded to the first and second sealing patterns formed in a manner that surrounds the vibration portion and the first and second mounting terminal metal films to seal the vibration portion.

[0024] (7) In still another embodiment of the present invention, the first and second mounting terminals are formed by thermally curing a conductive paste.

[0025] According to this embodiment, since the first and second mounting terminals are formed by immersing each of the two end portions of a piezoelectric vibration plate bonded with a thin film serving as a sealing component in a conductive paste and thermally curing it, the manufacturing cost can be reduced compared to forming the first and second mounting terminals by, for example, sputtering or evaporation.

[0026] (8) In another embodiment of the present invention, the film or the first and second films are films made of a heat-resistant resin.

[0027] According to this embodiment, since the film sealed so as to cover the exciting electrode of the piezoelectric vibration plate is made of a heat-resistant resin film, the film does not deform during the solder reflow process for mounting the piezoelectric vibration device.

[0028] (9) In one embodiment of the present invention, the film or the first and second films include a thermoplastic adhesive layer on at least one surface.

[0029] According to this embodiment, the film can be bonded to the piezoelectric vibration plate by overlapping the surface of the film having the thermoplastic adhesive layer on the piezoelectric vibration plate and performing heat and pressure bonding.

[0030] (10) In another embodiment of the present invention, the piezoelectric vibration plate is a crystal vibration plate.

[0031] According to this embodiment, since a crystal vibration plate is used as a piezoelectric vibration plate, a piezoelectric vibration device having excellent frequency-temperature characteristics is obtained.

[0032] (11) The manufacturing method of the piezoelectric vibration device involved in the present invention is to prepare a piezoelectric wafer in advance in order to manufacture a piezoelectric vibration plate, and the piezoelectric vibration plate has: a vibration portion including first and second excitation electrodes and a metal film for first and second mounting terminals respectively connected to the first and second excitation electrodes, and the manufacturing method of the piezoelectric vibration device includes: an outer shape forming step, forming the outer shapes of a plurality of piezoelectric substrates on the piezoelectric wafer; a piezoelectric vibration plate forming step, forming the first and second excitation electrodes on the two main surfaces of the plurality of piezoelectric substrates formed in the outer shape forming step, and forming a metal film on the piezoelectric substrate. The piezoelectric vibration plate is constructed by using a metal film to form the first and second mounting terminals connected to the first and second excitation electrodes respectively; a bonding step is to bond first and second sealing components to the two main surfaces of the piezoelectric vibration plate respectively to cover the first and second excitation electrodes on the two main surfaces of the plurality of piezoelectric vibration plates formed in the piezoelectric vibration plate forming step, wherein at least one of the first and second sealing components is a resin film; a splitting step is to split the plurality of piezoelectric vibration plates to which the first and second sealing components are bonded in the bonding step along one direction; mounting terminal forming a step of immersing both ends of the plurality of piezoelectric diaphragms divided in the dividing step in a conductive paste to form first and second mounting terminals connected to the first and second mounting terminal metal films, respectively; and a singulation step of singulating the piezoelectric diaphragms on which the first and second mounting terminals were formed in the mounting terminal forming step, wherein in the piezoelectric diaphragm forming step, the first mounting terminal metal film is formed on one end of the piezoelectric substrate sandwiching the vibration portion, and the second mounting terminal metal film is formed on the other end of the piezoelectric substrate sandwiching the vibration portion. In the bonding step, both ends of the film are bonded to the ends of the piezoelectric diaphragm sandwiching the vibration portion. In the mounting terminal forming step, the first mounting terminal is formed so as to cover the outer surface of one end of the film and the outer surface of one end of the piezoelectric diaphragm sandwiching the vibration portion, and the second mounting terminal is formed so as to cover the outer surface of the other end of the film and the outer surface of the other end of the piezoelectric diaphragm sandwiching the vibration portion.

[0033] According to the manufacturing method of the piezoelectric vibration device involved in the present invention, since in the piezoelectric vibration plate forming process, the first and second mounting terminal metal films respectively connected to the first and second excitation electrodes are formed on the two end portions of the piezoelectric substrate sandwiching the vibration portion, and in the mounting terminal forming process, the first and second mounting terminals respectively connected to the first and second mounting terminal metal films are formed in a manner covering the outer surfaces of the two end portions of the film bonded to at least one of the two main surfaces of the piezoelectric vibration plate in the bonding process and the outer surfaces of the two end portions of the piezoelectric vibration plate, even if the size of the first and second mounting terminal metal films sandwiching the vibration portion is reduced in order to enlarge the vibration portion, the size of the first and second mounting terminals formed on the outer surface of the film bonded to the piezoelectric vibration plate can be made into the size required for mounting.

[0034] Thus, without increasing the size of the piezoelectric vibration device, the vibration portion can be enlarged to improve vibration characteristics, and the bonding area of ​​the first and second mounting terminals required for mounting the piezoelectric vibration device can be ensured.

[0035] In addition, since the piezoelectric vibration device has first and second mounting terminals connected to the first and second excitation electrodes respectively on the outer surface of the resin film bonded to the piezoelectric vibration plate, there is no need to accommodate the piezoelectric vibration plate in a box-shaped base with mounting terminals and an open top surface as in the past, and an expensive base is not required.

[0036] Furthermore, since a resin film is bonded to at least one of the two main surfaces of the piezoelectric vibration plate to seal at least one of the first and second excitation electrodes, costs can be reduced compared to a structure sealed with a metal, ceramic, or glass cover.

[0037] Furthermore, in the segmentation step, the plurality of piezoelectric diaphragms, which were formed into a matrix wafer prior to the singulation step, are segmented along a single direction, such as the column direction, thereby enabling separation into the plurality of piezoelectric vibrators in each column and processing them as columns. Consequently, in the mounting terminal formation step, each of the ends of the plurality of piezoelectric diaphragms in each column, to which the thin film is bonded, can be dipped into a conductive paste to form the first and second mounting terminals connected to the first and second mounting terminal metal films, respectively. This reduces costs compared to forming the mounting terminals by, for example, sputtering or vapor deposition.

[0038] (12) In a preferred embodiment of the present invention, in the bonding process, the first and second sealing components are set as the first and second films made of the resin, and the two ends of the first and second films are bonded to the two ends of the piezoelectric vibration plate that clamp the vibration part. In the mounting terminal forming process, the first mounting terminal is formed in a manner that covers the outer surface of one of the two ends of the first and second films and the outer surface of one of the two ends of the piezoelectric vibration plate that clamp the vibration part, and the second mounting terminal is formed in a manner that covers the outer surface of the other of the two ends of the first and second films and the outer surface of the other of the two ends of the piezoelectric vibration plate that clamp the vibration part.

[0039] According to this embodiment, since the first and second mounting terminals are formed in a manner covering the outer surfaces of the two end portions of the first and second films bonded to the two main surfaces of the piezoelectric vibration plate, that is, formed on the outer surfaces of the first and second films on both the front and back surfaces, when the piezoelectric vibration device is mounted on a circuit substrate, etc., it can be mounted on either the front or back surface.

[0040] Furthermore, since the first and second thin films made of resin are bonded to both main surfaces of the piezoelectric vibration plate to seal the first and second excitation electrodes, a metal, ceramic, or glass cover for sealing is unnecessary, further reducing costs.

[0041] According to the piezoelectric vibration device involved in the present invention, the first and second mounting terminals respectively connected to the first and second mounting terminal metal films formed on the two end parts of the piezoelectric vibration plate sandwiching the vibration part are formed in a manner covering the outer surface of the resin film, and the resin film constitutes at least one of the first and second sealing parts joined to the piezoelectric vibration plate. Therefore, even if the size of the first and second mounting terminal metal films sandwiching the vibration part is reduced in order to enlarge the vibration part, the size of the first and second mounting terminals formed on the outer surface of the film joined to the piezoelectric vibration plate can be made into the size required for mounting.

[0042] Thus, without increasing the size of the piezoelectric vibration device, the vibration portion can be enlarged to improve vibration characteristics, and the bonding area of ​​the first and second mounting terminals required for mounting the piezoelectric vibration device can be ensured.

[0043] In addition, since the piezoelectric vibration device has first and second mounting terminals connected to the first and second excitation electrodes respectively on the outer surface of the resin film bonded to the piezoelectric vibration plate, there is no need to accommodate the piezoelectric vibration plate in a box-shaped base with mounting terminals and an open top surface as in the past, and an expensive base is not required.

[0044] Furthermore, since a resin film is bonded to at least one of the two main surfaces of the piezoelectric vibration plate to seal at least one of the first and second excitation electrodes, costs can be reduced compared to a structure sealed with a metal, ceramic, or glass cover. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 This is a schematic perspective view of a crystal oscillator according to one embodiment of the present invention.

[0046] Figure 2 It is composed Figure 1 A schematic three-dimensional diagram of the crystal vibration plate of a crystal oscillator.

[0047] Figure 3 yes Figure 2 Schematic top view of the crystal oscillating plate.

[0048] Figure 4 It is along Figure 3 A schematic cross-sectional view of line AA.

[0049] Figure 5 yes Figure 2 Schematic bottom view of the crystal oscillating plate.

[0050] Figure 6 yes Figure 1 A schematic top view of a crystal oscillator.

[0051] Figure 7 It is along Figure 6 BB line schematic cross-sectional view.

[0052] Figure 8 yes Figure 1 A schematic bottom view of a crystal oscillator.

[0053] Figure 9 This is a schematic perspective view showing another crystal oscillator.

[0054] Figure 10 yes Figure 9 A schematic top view of a crystal oscillator.

[0055] Figure 11 It is along Figure 10 A schematic cross-sectional view of line AA.

[0056] Figure 12 yes Figure 9 A schematic bottom view of a crystal oscillator.

[0057] Figure 13A It is schematically represented Figure 1 A schematic cross-sectional view of the manufacturing process of a crystal oscillator.

[0058] Figure 13B It is schematically represented Figure 1 A schematic cross-sectional view of the manufacturing process of a crystal oscillator.

[0059] Figure 13C It is schematically represented Figure 1 A schematic cross-sectional view of the manufacturing process of a crystal oscillator.

[0060] Figure 13D It is schematically represented Figure 1 A schematic cross-sectional view of the manufacturing process of a crystal oscillator.

[0061] Figure 13E It is schematically represented Figure 1 A schematic cross-sectional view of the manufacturing process of a crystal oscillator.

[0062] Figure 13F It is schematically represented Figure 1 A schematic cross-sectional view of the manufacturing process of a crystal oscillator.

[0063] Figure 14 It is a top view for explaining the dividing step.

[0064] Figure 15 This is a schematic perspective view of a crystal oscillator according to another embodiment of the present invention.

[0065] Figure 16 This is a schematic plan view of a crystal vibrating plate constituting a crystal oscillator according to still another embodiment of the present invention.

[0066] Figure 17 yes Figure 16 Schematic bottom view of the crystal oscillating plate.

[0067] Figure 18 Another embodiment of the present invention is Figure 7 Corresponding schematic cross-sectional view. DETAILED DESCRIPTION

[0068] Hereinafter, one embodiment of the present invention will be described in detail with reference to the accompanying drawings. In this embodiment, the invention will be described as being applied to a crystal oscillator as a piezoelectric vibration device.

[0069] Figure 1 This is a schematic perspective view of a crystal oscillator according to one embodiment of the present invention.

[0070] The crystal oscillator 1 of this embodiment includes an AT-cut crystal oscillating plate 2 and first and second resin films 3 and 4 as first and second sealing members respectively bonded to the entire surfaces of both principal surfaces of the crystal oscillating plate 2. The first and second resin films 3 and 4 of this embodiment are transparent.

[0071] First, the crystal vibrating plate 2 constituting the crystal vibrator 1 will be described.

[0072] Figure 2 yes Figure 1 A schematic perspective view of the crystal vibration plate 2, Figure 3 This is a schematic top view. Figure 4 It is along Figure 3 A schematic cross-sectional view of line AA, Figure 5 This is a rough top view.

[0073] The crystal oscillating plate 2 in this embodiment is an AT-cut crystal plate, manufactured by rotating a rectangular crystal plate 35° 15' around the X-axis, the crystal's crystal axis. The new axes after rotation are referred to as the Y' and Z' axes. The front and back principal surfaces of the AT-cut crystal plate define the XZ' plane. In this XZ' plane, the short side of the rectangular crystal oscillating plate 2, viewed from above, is oriented along the X-axis, while the long side of the crystal oscillating plate 2 is oriented along the Z' axis.

[0074] The crystal vibrating plate 2 includes a vibrating portion 21 having a generally rectangular shape when viewed from above, an outer frame portion 23 surrounding the vibrating portion 21 with a through portion 22 interposed therebetween, and a connecting portion 24 connecting the vibrating portion 21 and the outer frame portion 23. The vibrating portion 21, the outer frame portion 23, and the connecting portion 24 are integrally formed. The vibrating portion 21 and the connecting portion 24 are thinner than the outer frame portion 23. In other words, the vibrating portion 21 is thinner than the outer frame portion 23.

[0075] A pair of first and second excitation electrodes 25 and 26 are formed on the front and back principal surfaces of the vibrating portion 21, respectively. First and second mounting terminal metal films 17 and 18, electrically connected to the first and second excitation electrodes 25 and 26, are formed along the short sides of the crystal vibrating plate 2 on the outer frame portion 23 at both ends of the long side of the rectangular crystal vibrating plate 2 when viewed from above. These first and second mounting terminal metal films 17 and 18 are formed at both ends of the long side of the crystal vibrating plate 2, sandwiching the vibrating portion 21.

[0076] Furthermore, the two ends of the long side of the crystal oscillating plate 2 refer to the portions extending from one end to the other end of the long side of the crystal oscillating plate 2 to 1 / 4 of the length thereof, preferably, the portions extending from one end to the other end to 1 / 6 of the length thereof, respectively. The first and second mounting terminal metal films 17 and 18 may be formed on at least a portion of each of these portions.

[0077] Furthermore, both end portions of the first and second resin films 3 and 4 bonded to both main surfaces of the crystal vibrating plate 2 are bonded to the both end portions in the longitudinal direction of the crystal vibrating plate 2 .

[0078] like Figure 3 As shown, the first mounting terminal metal film 17 on one of the two main surfaces of the crystal oscillating plate 2 is provided in contact with a first seal pattern 201 described later and is wider in the width direction ( Figure 3 is formed wider in the left and right directions).

[0079] Compared with the first mounting terminal metal film 17, the width ( Figure 3 The second mounting terminal metal film 18 is narrow in the left-right direction along one ( Figure 3 The second mounting terminal metal film 18 is formed so as to surround a second extension portion 201b of the first seal pattern 201, which will be described later.

[0080] like Figure 5 As shown, the second mounting terminal metal film 18 on the other of the two main surfaces of the crystal oscillating plate 2 is provided in contact with the second seal pattern 202 described later and is wider in the width direction ( Figure 5 is formed wider in the left and right directions).

[0081] Compared with the second mounting terminal metal film 18, the width ( Figure 5 The first mounting terminal metal film 17 is narrow in the left and right directions along the other side of the crystal oscillating plate 2 ( Figure 5 The first mounting terminal metal film 17 is formed so as to surround a second extension portion 202b of the second seal pattern 202, which will be described later.

[0082] The first mounting terminal metal film 17 and the second mounting terminal metal film 18 of the crystal oscillating plate 2 are formed across both main surfaces of the crystal oscillating plate 2 , the end surfaces on the opposing long sides of the crystal oscillating plate 2 , and the end surfaces on the opposing short sides of the crystal oscillating plate 2 .

[0083] As will be described later, the first and second mounting terminal metal films 17 and 18 are formed on the Figure 1 First and second mounting terminals 27 and 28 are electrically connected to the outer surfaces of both ends of the long side of the rectangular crystal oscillator 1 in plan view. The first and second mounting terminals 27 and 28 are terminals for mounting the crystal oscillator 1 on a circuit board or the like.

[0084] In this embodiment, the vibration part 21 having a substantially rectangular shape in plan view is connected to the outer frame part 23 via a connection portion 24 provided at one corner thereof. Therefore, the stress acting on the vibration part 21 can be reduced compared to a structure in which the vibration part 21 is connected at two or more locations.

[0085] In this embodiment, the connection portion 24 protrudes from one side of the inner periphery of the outer frame portion 23 in the X-axis direction and is formed along the Z′-axis direction. Figure 1 The first and second mounting terminals 27 and 28 are directly bonded to a circuit board or the like by solder or the like. Therefore, it is conceivable that contraction stress acts in the longitudinal direction (Z′-axis direction) of the crystal oscillator, and this stress propagates to the vibrating portion, causing the oscillation frequency of the crystal oscillator to change easily.

[0086] In contrast, in this embodiment, since the connection portion 24 is formed along the direction of the contraction stress, the contraction stress can be prevented from propagating to the vibrating portion 21. Consequently, changes in the oscillation frequency when the crystal resonator 1 is mounted on a circuit board can be suppressed.

[0087] like Figure 3 As shown, on one of the two principal surfaces of the crystal oscillating plate 2, to which the first resin film 3 is bonded, a first seal pattern 201 is formed in a rectangular ring shape, surrounding the substantially rectangular vibrating portion 21 together with the first mounting terminal metal film 17. This first seal pattern 201 includes first extensions 201a, 201a, connected to the first mounting terminal metal film 17 and extending along the longitudinal direction (Z′-axis) of the crystal oscillating plate 2, and second extensions 201b, extending along the transverse direction (X-axis) of the crystal oscillating plate 2 and connecting the extended ends of each first extension 201a, 201a. The outer periphery of the connection between each first extension 201a, 201a and the second extension 201b is formed to maintain a predetermined distance from the second mounting terminal metal film 18, which extends along a portion of the circumference of each opposing longitudinal side of the crystal oscillating plate 2. The second extension 201b is connected to the first extraction electrode 203, which is drawn from the first excitation electrode 25.

[0088] Therefore, the first mounting terminal metal film 17 at one of the two longitudinal ends of the crystal vibrating plate 2 is electrically connected to the first excitation electrode 25 via the first seal pattern 201 and the first extraction electrode 203 .

[0089] Since the first mounting terminal metal film 17, which is wider than the second mounting terminal metal film 18, is formed into a rectangular ring shape on one of the two main surfaces of the crystal vibration plate 2 to which the first resin film 3 is bonded, so as to surround the vibration part 21 together with the first sealing pattern 201, the first resin film 3 can be firmly bonded in the rectangular ring area.

[0090] Furthermore, the second mounting terminal metal film 18 extends along one (1) of the crystal oscillating plate 2 which is rectangular in plan view so as to surround the second extension 201b of the first seal pattern 201 as described above. Figure 3 Since the first resin film 3 is formed along the periphery of the short side (to the right of the quartz crystal oscillating plate 2) and a portion of the periphery of each long side, the first resin film 3 is firmly bonded to the periphery of the short side and a portion of the periphery of each long side. As described later, when the end portion of the crystal oscillating plate 2 on the short side thereof bonded with the first resin film 3 is immersed in a conductive paste, the conductive paste is blocked by the second mounting terminal metal film 18, thereby preventing the conductive paste from penetrating into the second extension 201b of the first seal pattern 201.

[0091] An electrodeless region where no electrodes are formed is provided between the second extension portion 201 b extending along the short side of the crystal vibrating plate 2 and the second mounting terminal metal film 18 , thereby achieving insulation between the first seal pattern 201 and the second mounting terminal metal film 18 .

[0092] like Figure 5 As shown, on the other of the two principal surfaces of the crystal oscillating plate 2, to which the second resin film 4 is bonded, a second seal pattern 202 is formed in a rectangular ring shape, surrounding the substantially rectangular vibrating portion 21 together with the second mounting terminal metal film 18. This second seal pattern 202 includes first extensions 202a, 202a, connected to the second mounting terminal metal film 18 and extending along the longitudinal direction of the crystal oscillating plate 2, and second extensions 202b, extending along the transverse direction of the crystal oscillating plate 2 and connecting the extended ends of the first extensions 202a, 202a. The outer periphery of the connection between each first extension 202a, 202a and the second extension 202b is formed to maintain a predetermined distance from the first mounting terminal metal film 17, which extends along a portion of the circumference of each opposing longitudinal side of the crystal oscillating plate 2.

[0093] The second mounting terminal metal film 18 at the other of the two longitudinal ends of the crystal vibrating plate 2 is connected to the second extraction electrode 204 extracted from the second excitation electrode 26 . That is, the second mounting terminal metal film 18 and the second excitation electrode 26 are electrically connected.

[0094] Since the second mounting terminal metal film 18, which is wider than the first mounting terminal metal film 17, is formed into a rectangular ring shape on the other of the two main surfaces of the crystal vibration plate 2 to which the second resin film 4 is bonded, so as to surround the vibration part 21 together with the second sealing pattern 202, the second resin film 4 can be firmly bonded in the rectangular ring area.

[0095] Furthermore, the first mounting terminal metal film 17 extends along the other (102 mm) of the rectangular crystal vibrating plate 2 in a plan view so as to surround the second extension 202b of the second seal pattern 202 as described above. Figure 5 Since the second resin film 4 is formed along the periphery of the short side (to the left of the quartz crystal oscillating plate 2) and a portion of the periphery of each long side, the second resin film 4 is firmly bonded to the periphery of the short side and a portion of the periphery of each long side. Therefore, as described later, when the end portion of the crystal oscillating plate 2 on the short side thereof bonded with the second resin film 4 is immersed in a conductive paste, the conductive paste is blocked by the first mounting terminal metal film 17, thereby preventing the conductive paste from penetrating into the second extension portion 202b of the second seal pattern 202.

[0096] An electrodeless region where no electrodes are formed is provided between the second extension portion 202 b extending along the short side of the crystal vibrating plate 2 and the first mounting terminal metal film 17 , thereby achieving insulation between the second seal pattern 202 and the first mounting terminal metal film 17 .

[0097] like Figure 3 As shown, the widths of the first extensions 201a, 201a of the first seal pattern 201, which extend along the longitudinal direction of the crystal vibrating plate 2, are narrower than the width of the outer frame portion 23 extending along the longitudinal direction. Figure 3 Electrode-free areas where no electrodes are formed are provided on both sides (in the up and down directions).

[0098] The outermost electrodeless region of the electrodeless regions on either side of the first extensions 201a, 201a extends to the first mounting terminal metal film 17 and is connected to the electrodeless region between the second mounting terminal metal film 18 and the second extension 201b. Thus, the outer sides of the first extensions 201a, 201a, and the second extension 201b of the first seal pattern 201 are surrounded by electrodeless regions of substantially equal width. This electrodeless region extends along one first extension 201a, extending from the first mounting terminal metal film 17 side along the longitudinal direction of the crystal oscillating plate 2. It also extends from the end of the first extension 201a along the second extension 201b, and from the end of the second extension 201b along the other first extension 201a to the first mounting terminal metal film 17 side.

[0099] An electrodeless region is formed on the inner side of the first mounting terminal metal film 17 in the width direction. This electrodeless region is connected to the electrodeless region on the inner side of the first extensions 201a and 201a. An electrodeless region is formed on the inner side of the second extension 201b in the width direction, excluding the first extraction electrode 203 of the connecting portion 24. This electrodeless region is connected to the electrodeless region on the inner side of the first extensions 201a and 201a. As a result, the inner side of the first mounting terminal metal film 17, the first extensions 201a and 201b in the width direction, excluding the first extraction electrode 203 of the connecting portion 24, forms a rectangular ring-shaped electrodeless region when viewed from above.

[0100] like Figure 5 As shown, the widths of the first extensions 202a, 202a of the second seal pattern 202, which extend along the longitudinal direction of the crystal vibrating plate 2, are narrower than the width of the outer frame portion 23 extending along the longitudinal direction. Figure 5 Electrode-free areas where no electrodes are formed are provided on both sides (in the up and down directions).

[0101] The outermost electrodeless region of the electrodeless regions on either side of the first extensions 202a and 202b extends to the second mounting terminal metal film 18 and is connected to the electrodeless region between the first mounting terminal metal film 17 and the second extension 202b. Thus, the outer sides of the first extensions 202a and 202a and the second extension 202b of the second seal pattern 202 are surrounded by electrodeless regions of substantially equal width. This electrodeless region extends along one first extension 202a extending from the second mounting terminal metal film 18 side along the longitudinal direction of the crystal oscillating plate 2, extends from the extending end of the first extension 202a along the second extension 202b, and extends from the extending end of the second extension 202b along the other first extension 202a to the second mounting terminal metal film 18 side.

[0102] An electrodeless region is formed on the inner side of the second mounting terminal metal film 18 in the width direction, excluding the second extraction electrode 204 of the connecting portion 24. This electrodeless region is connected to the electrodeless region on the inner side of the first extensions 202a and 202a. An electrodeless region is formed on the inner side of the second extension 202b in the width direction, connecting to the electrodeless region on the inner side of the first extensions 202a and 202a. Thus, the inner side of the second mounting terminal metal film 18, the first extensions 202a and 202b in the width direction, excluding the second extraction electrode 204 of the connecting portion 24, forms a rectangular ring-shaped electrodeless region when viewed from above.

[0103] As described above, the first extensions 201a, 201a; 202a, 202a of the first and second sealing patterns 201, 202 are narrower than the width of the outer frame portion 23, and electrode-free regions are provided on both sides of the width direction of the first extensions 201a, 201a; 202a, 202a, and an electrode-free region is provided on the inner side of the width direction of the first and second mounting terminal metal films 17, 18 and the second extensions 201b, 202b. The electrode-free region is formed as follows: that is, the first and second sealing patterns 201, 202 that are wrapped around the side of the outer frame portion 23 during sputtering are patterned using photolithography technology and the first and second sealing patterns 201, 202 are removed by metal etching. In this way, short circuits caused by the first and second sealing patterns 201, 202 wrapping around the side of the outer frame portion 23 can be prevented.

[0104] The first and second resin films 3 and 4 are bonded to both main surfaces of the crystal oscillating plate 2 having the above structure, and the first and second mounting terminals 27 and 28 are formed as described later to obtain the above structure. Figure 1 Crystal oscillator 1.

[0105] Then, Figure 1 The crystal oscillator 1 shown will be described.

[0106] Figure 6 yes Figure 1 A schematic top view of the crystal oscillator 1 is shown in FIG. Figure 7 It is along Figure 6 A schematic cross-sectional view of line BB, Figure 8 1 is a schematic bottom view of the crystal oscillator 1. Figure 7 and the following Figures 13D to 13F In the figures, for convenience of explanation, the thickness of the resin film and the like is exaggerated.

[0107] The crystal oscillator 1 is a rectangular parallelepiped similar to the above-mentioned crystal oscillating plate 2 and has a rectangular shape in plan view. The crystal oscillator 1 of this embodiment has a size of, for example, 1.2 mm x 1.0 mm in plan view and a thickness of 0.2 mm, achieving miniaturization and low profile.

[0108] The size of the crystal oscillator 1 is not limited to the above, and a size different from this may be applied.

[0109] The first and second resin films 3 and 4, which are respectively bonded to the two main surfaces of the crystal oscillating plate 2 and sealed to cover the vibrating portion 21 of the crystal oscillating plate 2, are rectangular films. In this embodiment, the first and second resin films 3 and 4 have the same dimensions as the rectangular crystal oscillating plate 2 when viewed from above, and are bonded to the outer frame 23 of the crystal oscillating plate 2 to cover the thin vibrating portion 21 of the crystal oscillating plate 2.

[0110] In this manner, in order to cover the thin vibrating portion 21 , the first and second resin films 3 and 4 are bonded to the outer frame portion 23 , thereby sealing the internal space of the vibrating portion 21 .

[0111] In this embodiment, after the first and second resin films 3 and 4 are respectively bonded to the two main surfaces of the crystal vibration plate 2 which is rectangular when viewed from above, a conductive paste is applied to the two end portions in the long side direction of the crystal vibration plate 2 to which the first and second resin films 3 and 4 are bonded so as to cover the first and second resin films 3 and 4 and substantially the entire outer surface of the crystal vibration plate 2 and is thermally cured to form the first and second mounting terminals 27 and 28.

[0112] That is, the first mounting terminal 27 is formed on the surface opposite to the bonding surface of the first resin film 3 bonded to one of the two end portions in the longitudinal direction of the crystal vibrating plate 2 ( Figure 7 The upper surface in the middle) and the end surface of the thin first resin film 3, and formed on the surface opposite to the bonding surface of the second resin film 4 ( Figure 7 the lower surface in the middle) and the end surface of the thin second resin film 4.

[0113] Furthermore, the first mounting terminals 27 are formed on each of the opposing long-side end surfaces and one of the opposing short-side end surfaces of one of the two long-side end surfaces of the crystal oscillating plate 2. Since the first mounting terminal metal film 17 is formed on one of the two long-side end surfaces of the crystal oscillating plate 2, spanning both principal surfaces, each of the opposing long-side end surfaces, and one of the opposing short-side end surfaces, as described above, the first mounting terminals 27 are formed on and electrically connected to the first mounting terminal metal film 17 formed on each of the opposing long-side end surfaces and one of the opposing short-side end surfaces of the crystal oscillating plate 2.

[0114] Similarly, the second mounting terminal 28 is formed on the surface opposite to the bonding surface of the first resin film 3 bonded to the other of the two end portions in the longitudinal direction of the crystal vibrating plate 2 ( Figure 7 The upper surface in the middle) and the end surface of the thin first resin film 3, and formed on the surface opposite to the bonding surface of the second resin film 4 ( Figure 7 the lower surface in the middle) and the end surface of the thin second resin film 4.

[0115] Furthermore, the second mounting terminals 28 are formed on the other of the two end portions in the longitudinal direction of the crystal oscillating plate 2, on each of the opposing end surfaces of the long sides and on the other of the opposing end surfaces of the short sides. Since the second mounting terminal metal film 18 is formed at the other of the two end portions in the longitudinal direction of the crystal oscillating plate 2, spanning both principal surfaces, each of the opposing end surfaces of the long sides, and the other of the opposing end surfaces of the short sides, as described above, the second mounting terminals 28 are formed on and electrically connected to the second mounting terminal metal film 18 formed on each of the opposing end surfaces of the long sides and on the other of the opposing end surfaces of the short sides of the crystal oscillating plate 2.

[0116] In this way, since the first and second mounting terminals 27 and 28 electrically connected to the first and second mounting terminals of the crystal vibration plate 2 are formed on the outer surfaces of the first and second resin films 3 and 4 bonded to the crystal vibration plate 2, the size of the vibration part can be increased compared to a structure in which the first and second mounting terminals are formed on the crystal vibration plate.

[0117] Figure 9 This is a schematic perspective view of a crystal oscillator 1' in which first and second mounting terminals 27' and 28' are formed on a crystal oscillator plate 2'. Figure 10 yes Figure 9 A schematic top view of the crystal oscillator 1′ is shown in FIG. Figure 11 It is along Figure 10 A schematic cross-sectional view of line AA, Figure 12 yes Figure 9 A schematic bottom view of the crystal oscillator 1′.

[0118] These Figure 9 、 Figure 10 、 Figure 11 、 Figure 12 Corresponding to the present embodiment Figure 1 、 Figure 6 、 Figure 7 、 Figure 8 The outer dimensions of the crystal oscillator 1 ′ are the same as those of the crystal oscillator 1 of this embodiment.

[0119] Figures 9 to 12 The crystal oscillator 1' shown in FIG. 1 shows a crystal oscillator plate 2', similar to the present embodiment, comprising a vibrating portion 21'; an outer frame portion 23' surrounding the vibrating portion 21' with a through portion 22' interposed therebetween; and a connecting portion 24' connecting the vibrating portion 21' and the outer frame portion 23'. A pair of first and second excitation electrodes 25' and 26' are formed on the front and back principal surfaces of the vibrating portion 21', respectively. First and second seal patterns 201' and 202' are formed on the front and back principal surfaces of the crystal oscillator plate 2'.

[0120] In this crystal oscillator 1′, first and second mounting terminals 27′ ​​and 28′ are formed at either end of the crystal oscillating plate 2′ in the longitudinal direction. To expose the bonding areas required for mounting these first and second mounting terminals 27′ ​​and 28′, the first and second resin films 3′ and 4′ are formed to be relatively short along the longitudinal direction of the crystal oscillating plate 2′. Furthermore, the vibrating portion 21′, sealed by the first and second resin films 3′ and 4′, is relatively short along the longitudinal direction.

[0121] In contrast, in this embodiment, the first and second mounting terminals 27 and 28 are formed on the outer surfaces of the first and second resin films 3 and 4 bonded to the crystal oscillating plate 2, rather than being formed on the crystal oscillating plate 2. Figure 7 As shown, Figure 11 Compared with the first and second mounting terminals 27' and 28', the length of the first and second mounting terminal metal films 17 and 18 formed on the crystal vibration plate 2 along the long side direction of the crystal vibration plate 2 can be shortened, and Figure 11 Compared with the vibrating portion 21 ′, the length of the vibrating portion 21 sandwiched between the first and second mounting terminal metal films 17 and 18 along the longitudinal direction can be extended accordingly.

[0122] Thus, without increasing the size of the crystal oscillator 1 , the vibration portion 21 can be extended along the longitudinal direction of the crystal oscillator plate 2 to improve vibration characteristics, and the bonding area of ​​the first and second mounting terminals 27 and 28 required for mounting the crystal oscillator 1 can be ensured.

[0123] In this embodiment, the first and second resin films 3 and 4 are heat-resistant resin films, such as polyimide resin films, having a heat resistance of approximately 300°C. The polyimide resin first and second resin films 3 and 4 are transparent, but may become opaque depending on the heat and pressure bonding conditions described below. Alternatively, the first and second resin films 3 and 4 may be transparent, opaque, or translucent.

[0124] The first and second resin films 3 and 4 are not limited to polyimide resins, and resins classified as super engineering plastics, such as polyamide resins and polyetheretherketone resins, may also be used.

[0125] The first and second resin films 3 and 4 have thermoplastic adhesive layers formed entirely on their front and back surfaces. The rectangular perimeter edges of the first and second resin films 3 and 4 are heat-pressed, for example, onto the outer frame portions 23 of the two main surfaces of the crystal oscillating plate 2 to seal the oscillating portion 21.

[0126] Thus, since the first and second resin films 3 and 4 are heat-resistant resin films, they can withstand the high temperature of solder reflow processing when the crystal oscillator 1 is soldered and mounted on a circuit board, etc., without deformation.

[0127] The first and second excitation electrodes 25 and 26, the first and second extraction electrodes 203 and 204, the first and second seal patterns 201 and 202, and the first and second mounting terminal metal films 17 and 18 of the crystal vibrating plate 2 are formed by laminating Au, for example, on a base layer composed of Ti or Cr, and further laminating Ti, Cr, or Ni, for example.

[0128] In this embodiment, the base layer is Ti, and Au and Ti are stacked thereon. Thus, the uppermost layer being Ti improves the bonding strength with the polyimide resin compared to the case where Au is the uppermost layer.

[0129] Since the upper layers of the first and second mounting terminal metal films 17 and 18 and the first and second sealing patterns 201 and 202 bonded with the rectangular first and second resin films 3 and 4 are composed of Ti, Cr or Ni (or their oxides) as described above, the bonding strength with the first and second resin films 3 and 4 can be improved compared with Au and the like.

[0130] Next, a method for manufacturing the crystal oscillator 1 according to this embodiment will be described.

[0131] Figures 13A to 13F It is a schematic cross-sectional view showing the steps of manufacturing the crystal oscillator 1 .

[0132] First, prepare Figure 13A The crystal wafer (AT cut crystal plate) 5 before processing is shown. For the crystal wafer 5, photolithography technology and etching technology, such as wet etching, are used. Figure 13B As shown, the outer shapes of multiple crystal substrate parts 2a and the frame parts (not shown) supporting them are formed, and then the outer shapes of the outer frame part 23a and the vibration part 21a thinner than the outer frame part 23a are formed in the crystal substrate part 2a, that is, the outer shape forming process is performed.

[0133] In addition, the plurality of crystal substrate portions 2a are connected along the frame portion and the like. Figure 13B The direction perpendicular to the paper is the column direction and Figure 13B The left and right directions, i.e. the row directions, are connected and supported in a matrix shape.

[0134] Then, if Figure 13CThe crystal oscillating plate forming step is performed as shown, i.e., the first and second excitation electrodes 25a, 26a and the first and second mounting terminal metal films 17a, 18a are formed at predetermined positions on the crystal substrate portion 2a by sputtering technology, vapor deposition technology, and photolithography technology to construct the crystal oscillating plate 2b.

[0135] Then, if Figure 13D The bonding process is performed as shown, that is, the resin films 3a and 4a are heated and pressed so that the entire surfaces of the two main surfaces of the plurality of crystal vibrating plates 2b connected and supported in a matrix are covered with continuous resin films 3a and 4a, thereby sealing the vibration parts 21a of each crystal vibrating plate 2b.

[0136] The sealing of each vibration portion 21 a by the resin films 3 a and 4 a is performed in an inert gas atmosphere such as nitrogen.

[0137] Next, a dividing step is performed to separate the plurality of crystal oscillating plates 2b in a matrix with the resin films 3a and 4a bonded thereto. Figure 13E As shown, only the column direction ( Figure 13E In this dividing step, the continuous resin films 3a, 4a and the crystal oscillating plate 2b are cut in the column direction and unnecessary portions are removed.

[0138] Figure 14 This is a top view showing an example of division of the crystal oscillating plate 2b in the column direction. Figure 14 In FIG. 1 , a portion of six crystal vibrating plates 2 b arranged in three rows and two columns is simplified.

[0139] Along the Figure 14 The crystal oscillating plates 2b are divided in the vertical direction, that is, the column direction, and separated into a plurality of, for example, three, crystal oscillating plates 2b in a column unit surrounded by a dotted line L. Thus, a plurality of crystal oscillating plates 2b can be processed in a column unit.

[0140] Furthermore, as another embodiment of the present invention, a plurality of crystal oscillating plates may be divided in the row direction and processed in row units instead of being divided in the column direction.

[0141] Next, a mounting terminal forming step is performed, i.e., each end portion of the plurality of crystal oscillating plates 2b of each divided row is immersed in a conductive paste such as silver paste or copper paste and thermally cured to form first and second mounting terminals 27 and 28, respectively. Then, a singulation step is performed, i.e., each crystal oscillating plate 2b having the first and second mounting terminals 27 and 28 formed thereon is singulated, thereby forming a plurality of crystal oscillating plates 2b. Figure 13FAs shown, multiple crystal resonators 1 are obtained. In this embodiment, silver paste is used as the conductive paste. The silver paste contains silver (Ag), nickel (Ni), palladium (Pd), etc. as conductive fillers. Examples of binder resins for the silver paste include epoxy resins, imide resins, polyurethane resins, and silicone resins.

[0142] In the mounting terminal forming process, Figure 13E 、 Figure 13F As shown, each of the two ends of the crystal oscillating plate 2b is immersed in a conductive paste and then thermally cured to form the first and second mounting terminals 27 and 28, respectively. As described above, the first and second mounting terminals 27 and 28 are electrically connected to the first and second mounting terminal metal films 17 and 18 of the crystal oscillating plate 2. Thus, the longitudinal ends of the crystal oscillating plate 2b, to which the first and second resin films 3 and 4 are bonded, are covered by the first and second mounting terminals 27 and 28, which are formed from a mixed layer of conductive filler and binder resin.

[0143] In this way, since the first and second mounting terminals 27 and 28 can be formed by immersing the respective ends in the long side direction of the crystal vibration plate 2b bonded with the first and second resin films 3 and 4 in a conductive paste and thermally curing it, the manufacturing cost can be reduced compared to forming the first and second mounting terminals 27 and 28 by, for example, sputtering or evaporation.

[0144] Furthermore, in the above-mentioned dividing step, dividing is performed along one direction. However, as another embodiment of the present invention, in the dividing step, dividing may be performed along two directions, one direction and another direction orthogonal to the one direction, that is, singulation may be performed.

[0145] As described above, according to this embodiment, the vibration portion 21 can be extended in the longitudinal direction of the crystal vibrating plate 2 to improve vibration characteristics without increasing the size of the crystal vibrator 1 , and the bonding area of ​​the first and second mounting terminals 27 and 28 required for mounting the crystal vibrator 1 can be ensured.

[0146] In addition, since the crystal oscillator 1 has first and second mounting terminals 27 and 28 connected to the first and second excitation electrodes 25 and 26 respectively on the outer surfaces of the first and second resin films 3 and 4 bonded to the crystal vibration plate 2, it is not necessary to accommodate the piezoelectric vibration piece in a box-shaped base made of an insulating material such as ceramic with mounting terminals and an open upper surface as in the past, and an expensive base is not required.

[0147] Furthermore, since the first and second resin films 3 and 4 are bonded to both main surfaces of the crystal vibrating plate 2 to seal the first and second excitation electrodes 25 and 26 , a metal, ceramic, or glass cover for sealing is unnecessary.

[0148] This makes it possible to reduce the cost of the crystal oscillator 1 and provide the crystal oscillator 1 at low cost.

[0149] Furthermore, compared with the conventional example in which a piezoelectric vibrating reed is mounted in a box-shaped base and sealed with a lid, a thinner (lower) configuration can be achieved.

[0150] In the crystal oscillator 1 of this embodiment, since the vibration part 21 is sealed by the first and second resin films 3 and 4, the airtightness is poorer than the existing example in which a metal, ceramic or glass cover is bonded to a base for airtight sealing, and the resonance frequency of the crystal oscillator 1 is prone to change over time.

[0151] However, for example, in Bluetooth (registered trademark) Low Energy (BLE) for short-range wireless communication, since the standards for frequency deviation and the like are relatively loose, an inexpensive crystal resonator 1 sealed with a resin film can be used in such applications.

[0152] In the above embodiment, the length of the vibrating portion 21 is extended along the Z′ axis direction of the crystal vibrating plate 2. However, as another embodiment of the present invention, Figure 15 As shown, the length of the vibrating portion 21 can also be extended along the X-axis direction of the crystal vibrating plate 2. In this case, the first and second mounting terminals 27 and 28 are preferably formed at both ends of the crystal vibrating plate 2 in the X-axis direction. Furthermore, in the above embodiment, the connecting portion 24 is provided at one corner of the vibrating portion 21, which is substantially rectangular in plan view. However, the location and number of connecting portions 24 are not limited to this. Furthermore, the width of the connecting portion 24 does not need to be constant.

[0153] Alternatively, the invention may be applied to an inverted-concave crystal vibrating plate having a thin vibrating portion and a thick peripheral portion without the through portion.

[0154] In the above embodiment, the first and second resin films 3 and 4 are bonded to both main surfaces of the crystal vibrating plate 2 to seal the vibrating portion 21 . However, the resin film may be bonded to only one main surface of the crystal vibrating plate 2 , and a conventional cover may be bonded to the other main surface to seal the vibrating portion 21 .

[0155] In the above embodiment, the first and second mounting terminals are formed respectively by using metal films 17 and 18 to span the two main surfaces of the crystal vibration plate 2 and the end surfaces of the opposite long sides and short sides of the crystal vibration plate 2. However, the first and second mounting terminals can be electrically connected to the first and second mounting terminals 27 and 28 respectively, and can also be formed on at least any one of the two main surfaces of the crystal vibration plate 2, the end surfaces of the opposite long sides and the end surfaces of the short sides of the crystal vibration plate 2.

[0156] In the above embodiment, the first and second resin films 3 and 4 have a size that covers the entire two main surfaces of the crystal vibrating plate 2. However, the first and second resin films 3 and 4 only need to have a size that allows both ends to be bonded to both ends of the long side of the crystal vibrating plate 2.

[0157] In the above embodiment, if Figure 3 As shown, on one of the two main surfaces of the crystal vibrating plate 2, the first seal pattern 201 is formed in a rectangular ring shape so as to surround the substantially rectangular vibrating portion 21 together with the first mounting terminal metal film 17. Figure 5 As shown, on the other of the two main surfaces of the crystal vibrating plate 2, the second seal pattern 202 is formed in a rectangular ring shape so as to surround the substantially rectangular vibrating portion 21 together with the second mounting terminal metal film 18. However, the rectangular ring-shaped first and second seal patterns 201 and 202 may be omitted.

[0158] Figure 16 and Figure 17 The schematic top view and bottom view of the crystal vibration plate 21 with the first and second seal patterns 201 and 202 omitted are respectively corresponding to the above-mentioned embodiment. Figure 3 and Figure 5 Picture.

[0159] In the crystal vibrating plate 21 , the first and second mounting terminal metal films 171 and 181 are formed on a portion of the peripheral edge portions of the opposing short sides across both main surfaces of the crystal vibrating plate 21 .

[0160] The first mounting terminal metal film 171 is formed on a portion of the peripheral edge of one short side. Figure 16 As shown, it is electrically connected to the first excitation electrode 25 through the lead-out electrode 205 and the first lead-out electrode 203 .

[0161] The second mounting terminal metal film 181 is formed on a portion of the peripheral edge of the other short side. Figure 17 As shown, the second extraction electrode 204 is extended and electrically connected to the second excitation electrode 26 .

[0162] The other structures are the same as those in the above embodiment.

[0163] In the crystal vibrating plate 21 in which the rectangular ring-shaped first and second seal patterns 201 and 202 are omitted, a photosensitive resin film may be used as the resin film.

[0164] For example, as mentioned above Figure 13DAs shown, a crystal wafer can also be prepared in which multiple crystal oscillating plates 21 are arranged and supported in a matrix. A photosensitive resin film can be attached to each of the two main surfaces of the crystal wafer. The photosensitive resin film is exposed and developed to cover the first and second excitation electrodes of the crystal oscillating plates 21, and patterned to remove unnecessary portions and then cured. Subsequently, the multiple crystal oscillating plates 21 in the wafer form can be divided along the column direction as described above, immersed in a conductive paste, and thermally cured, thereby singulating the individual crystal oscillating plates 21.

[0165] As another embodiment of the present invention, Figure 18 As shown, for example, for the purpose of improving solderability, a metal film 29 may be formed on the first and second mounting terminals 27 and 28 .

[0166] The metal film 29 may be a single layer or multiple layers. A single layer metal film 29 is preferably made of nickel (Ni), tin (Sn), or gold (Au). A two-layer metal film 29 is preferably made of Ni-Sn, Ni-Au, or Ni-Cu. A three-layer metal film 29 is preferably made of Cu-Ni-Sn, Cu-Ni-Au, or the like.

[0167] The crystal vibration plate only needs to be roughly rectangular when viewed from above, and is not limited to the above-mentioned rectangular shape when viewed from above. For example, it can also be a shape in which the corners of the crystal vibration plate are chamfered, or a shape having a castle-shaped structure, etc., in which the peripheral edge of the crystal vibration plate is cut in the thickness direction and the cut portion is covered with an electrode.

[0168] The present invention is not limited to piezoelectric resonators such as crystal resonators, but can also be applied to other piezoelectric vibration devices such as piezoelectric oscillators.

[0169] Description of Reference Signs

[0170] 1.12 Quartz crystal oscillator

[0171] 2.21 Crystal Vibration Plate

[0172] 3. First resin film

[0173] 4 Second resin film

[0174] 5 crystal wafers

[0175] 17 Metal film for the first mounting terminal

[0176] 18 Metal film for second mounting terminal

[0177] 21 Vibration Department

[0178] 23 outer frame

[0179] 24 Connection

[0180] 25 First excitation electrode

[0181] 26 Second excitation electrode

[0182] 27 First mounting terminal

[0183] 28 Second mounting terminal

[0184] 201 First Seal Pattern

[0185] 202 Second sealing pattern

Claims

1. A piezoelectric vibration device comprising: a piezoelectric vibration plate having a vibration portion including first and second excitation electrodes and first and second mounting terminal metal films connected to the first and second excitation electrodes, respectively; and The first and second sealing members are bonded to the two main surfaces of the piezoelectric vibration plate so as to cover the first and second excitation electrodes formed on the two main surfaces of the piezoelectric vibration plate, respectively. At least one of the first and second sealing members is a resin film. The first mounting terminal metal film is formed on one of the two ends of the piezoelectric vibration plate sandwiching the vibration portion, and the second mounting terminal metal film is formed on the other of the two ends. Both ends of the film are joined to both ends of the piezoelectric vibration plate sandwiching the vibration portion. A first mounting terminal connected to the first mounting terminal metal film is formed so as to cover the outer surface of one of the two end portions of the film, and a second mounting terminal connected to the second mounting terminal metal film is formed so as to cover the outer surface of the other of the two end portions of the film. The piezoelectric vibration plate includes an outer frame portion connected to the vibration portion via a connecting portion, wherein the outer frame portion surrounds the outer periphery of the vibration portion which is thinner than the outer frame portion with a gap. The first and second mounting terminal metal films are respectively formed on the outer frame portion, The first and second sealing members are respectively bonded to the outer frame to seal the first and second excitation electrodes of the vibration part. A first sealing pattern is formed on one of the two main surfaces of the outer frame portion, the first sealing pattern being connected to the first mounting terminal metal film, surrounding the vibrating portion together with the first mounting terminal metal film, and being bonded to the first sealing component. A second sealing pattern is formed on the other of the two main surfaces of the outer frame portion, the second sealing pattern being connected to the second mounting terminal metal film, surrounding the vibrating portion together with the second mounting terminal metal film, and being bonded to the second sealing component. The width of the extension portion of each of the first seal pattern and the second seal pattern is smaller than the width of the outer frame portion, thereby forming electrode-free regions on both sides of the extension portion in the width direction.

2. The piezoelectric vibration device according to claim 1, wherein The first and second sealing members are the first and second films made of the resin. Both ends of the first and second films are bonded to both ends of the piezoelectric vibration plate sandwiching the vibration portion. A first mounting terminal connected to the first mounting terminal using a metal film is formed in a manner covering the outer surface of one of the two end portions of the first and second films, and a second mounting terminal connected to the second mounting terminal using a metal film is formed in a manner covering the outer surface of the other of the two end portions of the first and second films.

3. The piezoelectric vibration device according to claim 2, wherein The first mounting terminal is formed in a manner that covers the entire outer surface of one end portion of the first and second films and the outer surface of one of the two end portions of the piezoelectric vibration plate sandwiching the vibration portion, and the second mounting terminal is formed in a manner that covers the entire outer surface of the other end portion of the first and second films and the outer surface of the other of the two end portions of the piezoelectric vibration plate sandwiching the vibration portion.

4. The piezoelectric vibration device according to claim 2, wherein The first and second mounting terminals are formed by metal films spanning the two main surfaces and the end surface of the outer frame. The first and second films are bonded to the first and second mounting terminal metal films formed on the two main surfaces of the outer frame portion, respectively.

5. The piezoelectric vibration device according to claim 3, wherein The first and second mounting terminals are formed by metal films spanning the two main surfaces and the end surface of the outer frame. The first and second films are bonded to the first and second mounting terminal metal films formed on the two main surfaces of the outer frame portion, respectively.

6. The piezoelectric vibration device according to any one of claims 1 to 5, wherein The first and second mounting terminals are formed by thermally curing a conductive paste.

7. The piezoelectric vibration device according to any one of claims 1 to 5, wherein The film or the first and second films are films made of a heat-resistant resin.

8. The piezoelectric vibration device according to any one of claims 1 to 5, wherein The film or the first and second films may include a thermoplastic adhesive layer on at least one surface.

9. The piezoelectric vibration device according to any one of claims 1 to 5, wherein The piezoelectric vibration plate is a crystal vibration plate.

10. A method for manufacturing a piezoelectric vibration device, A piezoelectric wafer is prepared in advance for manufacturing a piezoelectric vibration plate having a vibration portion including first and second excitation electrodes and first and second mounting terminal metal films connected to the first and second excitation electrodes, respectively. The manufacturing method of the piezoelectric vibration device includes: an outer shape forming step of forming outer shapes of a plurality of piezoelectric substrates on the piezoelectric wafer; a piezoelectric diaphragm forming step of forming the first and second excitation electrodes on the two main surfaces of the plurality of piezoelectric substrates formed in the outer shape forming step, and forming metal films for the first and second mounting terminals connected to the first and second excitation electrodes, respectively, on the piezoelectric substrates to construct the piezoelectric diaphragm; a bonding step of bonding first and second sealing members to the two main surfaces of the piezoelectric vibration plate, respectively, so as to cover the first and second excitation electrodes on the two main surfaces of the plurality of piezoelectric vibration plates formed in the piezoelectric vibration plate forming step, wherein at least one of the first and second sealing members is a resin film; a dividing step of dividing the plurality of piezoelectric vibration plates to which the first and second sealing members are bonded in the bonding step along one direction; a mounting terminal forming step of immersing both end portions of the plurality of piezoelectric diaphragms divided in the dividing step into a conductive paste to form first and second mounting terminals connected to the first and second mounting terminal metal films, respectively; and a singulation step of singulating the piezoelectric vibration plates on which the first and second mounting terminals are formed in the mounting terminal forming step; In the piezoelectric diaphragm forming step, the first mounting terminal metal film is formed on one of the two ends of the piezoelectric substrate sandwiching the vibrating portion, and the second mounting terminal metal film is formed on the other of the two ends of the piezoelectric substrate sandwiching the vibrating portion. In the bonding step, both ends of the film are bonded to both ends of the piezoelectric vibration plate sandwiching the vibration portion. In the mounting terminal forming process, the first mounting terminal is formed in a manner that covers the outer surface of one of the two end portions of the film and the outer surface of one of the two end portions of the piezoelectric vibration plate that clamps the vibration part, and the second mounting terminal is formed in a manner that covers the outer surface of the other of the two end portions of the film and the outer surface of the other of the two end portions of the piezoelectric vibration plate that clamps the vibration part.

11. The method for manufacturing a piezoelectric vibration device according to claim 10, wherein: In the bonding step, the first and second sealing members are formed as first and second films made of the resin, and both ends of the first and second films are bonded to both ends of the piezoelectric vibration plate sandwiching the vibration portion. In the mounting terminal forming process, the first mounting terminal is formed in a manner that covers the outer surface of one of the two end portions of the first and second films and the outer surface of one of the two end portions of the piezoelectric vibration plate that clamps the vibration part, and the second mounting terminal is formed in a manner that covers the outer surface of the other of the two end portions of the first and second films and the outer surface of the other of the two end portions of the piezoelectric vibration plate that clamps the vibration part.

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