JP7290062B2 - Container for piezoelectric vibration device and piezoelectric vibration device using the container - Google Patents

Description

The present invention relates to a container constituting a piezoelectric vibration device used as a timing device for various electronic devices, and a piezoelectric vibration device using the container.

In recent years, piezoelectric vibrating devices have become ultra-compact. For example, in the case of a surface-mounted crystal resonator that is substantially rectangular in plan view, the outer dimensions in plan view have become as small as 1.0 mm or less in the long side and 0.8 mm or less in the short side.

For example, as shown in FIG. 8, the above-described surface-mounted crystal oscillator has a container 18 having a concave portion 19 opening upward, and a pair of projections 5, 5 projecting from the inner bottom surface of the concave portion 19. A crystal vibrating piece 2 is bonded onto a pair of mounting pads 6, 6 provided via conductive adhesives S, S, and a lid 4 is bonded to the open end of a container 18 so as to cover a recess 19. It is composed by In the crystal oscillator 17 shown in FIG. 8, the container 18 is a laminate of two ceramic green sheets in order to cope with miniaturization and thinning of the crystal oscillator. , and an upper plate portion 181 on the upper layer of the bottom plate portion 180 . A depression is formed in the upper plate portion 181 by punching, and the depression serves as the recess 19 . Crystal oscillators using such a container are disclosed in, for example, Patent Documents 1 and 2.

Patent No. 6368597 JP 2017-5673

In the crystal resonator 17 shown in FIG. 8 described above, internal wiring is formed between the layers between the upper plate portion 181 and the bottom plate portion 180 of the container 18 . Specifically, internal wirings 26 and internal wirings 27 are formed on an upper surface 1801 of the bottom plate portion 180 as shown in a schematic top view of the bottom plate portion 180 shown in FIG.

One of the pair of mounting pads 6, 6 described above is connected to the internal wiring 26 via a via V8 (not shown in FIG. 8) in which a conductor is filled in a through hole penetrating through the upper plate portion 181 in its thickness direction. It is The one mounting pad 6 is electrically connected to an external connection terminal 25d located below the via V10 via the via V10 connected to the internal wiring 26 (see FIG. 10).

Similarly, the other of the pair of mounting pads 6, 6 described above is connected to the internal wiring 27 via a via V9 (not shown in FIG. 8) provided in the upper plate portion 181. As shown in FIG. The other mounting pad 6 is electrically connected to the external connection terminal 25b located below the via V11 via the via V11 connected to the internal wiring 27. As shown in FIG. In FIG. 9, the portions where the via V8 (the same applies to the via V9) described above are connected to the internal wiring 26 (27) are shown hatched as V8 and V9 for the sake of convenience.

As shown in FIG. 10, the four external connection terminals (25a, 25b, 25c, 25d) include the four corners of the bottom surface 1802 (rectangular in plan view) of the bottom plate portion 180, and the bottom surface 1802 of the bottom plate portion 180 It is formed along each peripheral edge of two opposing long sides and two opposing short sides without leaving a gap in the direction toward the center.

Both ends 26 a and 26 b of the internal wiring 26 are exposed to the outside (corners) of the container 17 from between the lamination of the upper plate portion 181 and the bottom plate portion 180 . Similarly, one end 27a of the internal wiring 27 (to be described later) and one end 29a of the plating line 29 (to be described later) are also exposed to the outside (corner) of the container 17 from between the lamination of the upper plate portion 181 and the bottom plate portion 180. The other end portion 27b of the internal wiring 27, which will be described later, and the one end portion 28a of the plating line 28, which will be described later, are exposed to the outside (side portion) of the container 17 from between the layers of the upper plate portion 181 and the bottom plate portion 180. . The reason why the internal wirings 26, 27 and the plating lines 28, 29 extend so as to be exposed to the outside of the container 17 is that a large number of containers 18, 18, . This is because the internal wirings 26, 27 and the plating lines 28, 29 are collectively formed by plating in the state of a collective board aligned in parallel, so it is necessary to connect the internal wirings and the plating lines between adjacent containers.

The pair of mounting pads 6, 6 are pads connected to a pair of excitation electrodes (reference numerals omitted in FIG. 8) formed on the front and back main surfaces of the vibrating portion of the crystal vibrating piece 2, and have different polarities. . That is, one pole of the pair of mounting pads 6, 6 is electrically connected to the external connection terminal 25d via the internal wiring 26, and the other pole of the pair of mounting pads 6, 6 connects the internal wiring 27. It is electrically connected to the external connection terminal 25b via.

On the other hand, as shown in FIG. 9, on the upper surface 1801 of the bottom plate portion 180, two plating lines 28, 29 which are not electrically connected to the pair of mounting pads 6, 6 are formed apart from each other. One end portion 28 a of the plating line 28 is exposed to the outside (side portion) of the container 17 from between the layers of the upper plate portion 181 and the bottom plate portion 180 . A via V12 is connected in the vicinity of the other end (reference numeral omitted) of the plating line 28, and the lower end of the via V12 is electrically connected to the external connection terminal 25a. The external connection terminal 25a is a non-connection terminal (so-called no-connect (NC) terminal) that is not connected to any pole.

One end portion 29 a of the plating line 29 is exposed to the outside (corner portion) of the container 17 from between the lamination of the upper plate portion 181 and the bottom plate portion 180 . A via V13 is connected in the vicinity of the other end (reference numeral omitted) of the plating line 29, and the lower end of the via V13 is electrically connected to the external connection terminal 25c. The external connection terminal 25c is connected via vias (not shown in FIG. 8 and reference numerals omitted in FIG. 9) provided in the upper plate portion 181 and electrodes provided on the inner wall surface of the frame-shaped wall portion surrounding the recess 19. and is electrically connected to the metal lid 4 . This external connection terminal 25c serves as a ground terminal (so-called earth terminal) that is grounded to a ground potential.

For example, the crystal unit 17 described above has a long side of 1.0 mm or less, a short side of 0.8 mm or less, and an ultra-thin bottom plate portion for low profile. When it comes down to it, the following problems arise: That is, as shown in FIG. 11, the four external connection terminals 25a to 25d of the crystal oscillator 17 are connected to lands (L, L, L, L) provided on one main surface side of the external substrate P (PCB substrate). When the solder 33 is used for bonding, if the amount of the solder 33 exceeds a predetermined amount, both ends 26a, 26b, 27a, and 27b of the internal wirings 26 and 27 exposed on the outer surface of the container 18, and The solder 33 may crawl up and come into contact with the one ends 28a, 29a of the plating patterns 28, 29. As shown in FIG. In particular, if the one end 26a of the internal wiring 26 is contacted by the solder 33 crawling up from the land that is joined to the external connection terminal 25a, the external connection terminal 25a will move from the internal wiring 26 to the external connection terminal 25d through the via V10. It will be conductive. Thus, when the external connection terminal 25a and the external connection terminal 25d are electrically connected, the electrical characteristics of the crystal oscillator 17 may change. Such a phenomenon is particularly likely to occur in a container having a configuration (flush) in which the bottom plate portion 180 is very thin and the outer peripheral edge of the external connection terminal extends to the peripheral edge of the bottom plate portion.

The present invention has been made in view of this point, and provides a container capable of preventing changes in electrical characteristics of a piezoelectric vibration device even when it is ultra-compact and thin, and a piezoelectric vibration device using the container. It is intended to provide

In order to achieve the above object, the invention of claim 1 provides a container which is substantially rectangular in plan view and in which a piezoelectric vibrating piece is housed, wherein one side of a pair of opposing sides of one main surface of the container is provided with the piezoelectric vibrating piece. A pair of mounting pads to be joined to the vibrating reed is provided, and the pair of mounting pads are provided at the four corners of the other principal surface of the container opposite to the one principal surface via the internal wiring of the container. Each of the four external connection terminals is connected to two obliquely opposed external connection terminals. A routed wiring is routed to an external connection terminal corresponding to the other side of a pair of opposing sides and has an end exposed on the outer surface of the container, and at least one end of the routed wiring is a bottom plate portion that does not overlap with the four external connection terminals in plan view transmission, the container is a laminate of a plurality of layers made of an insulating material, and at least the internal wiring is the lowest layer of the container; The container is arranged between the upper layer of the bottom plate portion and the thickness of the bottom plate portion is 0.035 mm or more and 0.055 mm or less .

According to the above invention, even if the amount of solder is larger than the predetermined amount because at least one end of the lead-out wiring does not overlap the four external connection terminals in plan view transmission. Also, it is possible to prevent the contact of the solder with the end of the routed wiring exposed on the outer surface of the container. In particular, among the ends of the routing wiring, the solder creeps up to the end that does not overlap with the external connection terminal electrically connected to the routing wiring in a plan view, and is electrically connected to the routing wiring. It is possible to prevent electrical continuity between the external connection terminal and the external connection terminal joined by the solder creeping up to the end. This makes it possible to prevent changes in the electrical characteristics of the piezoelectric vibration device.

According to the above invention, the bottom plate portion has a thickness of 0.035 mm or more and 0.055 mm or less, which is very thin, and the internal wiring is provided between at least the bottom plate portion serving as the lowest layer of the container and the upper layer of the bottom plate portion. In a low-profile container with an arranged configuration, it is suitable for preventing contact of solder with the end of the lead-out wiring exposed on the outer surface of the container. In addition, when the thickness of the bottom plate portion is 0.035 mm or less, it is not preferable because it becomes difficult to handle in manufacturing the container. On the other hand, when the thickness of the bottom plate portion is 0.055 mm or more, the risk of the solder creeping up and coming into contact with the end portion of the routing wiring is reduced.

In order to achieve the above object, the invention according to claim 2 is characterized in that a region of the routing wiring excluding a region overlapping an external connection terminal corresponding to the other side of the pair of opposing sides in plan view is It is located in a region between two external connection terminals adjacent to each other.

According to the above invention, the area of the routing wiring excluding the area overlapping in plan view with the external connection terminal corresponding to the other side of the pair of opposing sides is two external connection terminals that are adjacent to each other in plan view transmission. located in the area between As a result, even when the amount of solder is greater than the predetermined amount, the end portion of the lead-out wiring exposed on the outer surface of the container can be kept away from the outer peripheral edge of the external connection terminal. It is possible to prevent solder from contacting the part.

Further, in order to achieve the above object, the invention of claim 3 is configured such that the piezoelectric vibrating piece is housed in the container according to claim 1 or 2, and the piezoelectric vibrating piece is hermetically sealed by joining a lid to the container. It is a piezoelectric vibration device sealed in the

According to the above invention, it is possible to obtain a piezoelectric vibration device in which solder is prevented from contacting the end portion of the routing wiring exposed on the outer surface of the container. In particular, among the ends of the routing wiring, the solder creeps up to the end that does not overlap with the external connection terminal electrically connected to the routing wiring in a plan view, and is electrically connected to the routing wiring. It is possible to obtain a piezoelectric vibration device that prevents electrical continuity between the external connection terminal and the external connection terminal joined by the solder that crawls up to the end.

As described above, according to the present invention, it is possible to provide a container capable of preventing changes in the electrical characteristics of a piezoelectric vibration device even when it is ultra-compact and thin, and a piezoelectric vibration device using the container. can be done.

Schematic cross-sectional view of a crystal oscillator according to an embodiment of the present invention FIG. 2 is a schematic top view of the quartz oscillator according to the embodiment of the present invention, excluding the lid; A schematic top view of the upper plate portion of the container according to the embodiment of the present invention. Schematic top view of a bottom plate portion of a container according to an embodiment of the present invention A schematic bottom view of the bottom plate portion of the container according to the embodiment of the present invention. The perspective view seen from the upper surface side of the bottom plate portion of the container according to the embodiment of the present invention. The perspective view seen from the upper surface side of the bottom plate portion of the container according to the modification of the embodiment of the present invention. Schematic cross-sectional view of a conventional crystal oscillator Schematic top view of bottom plate of conventional container Schematic diagram of the underside of the bottom plate of a conventional container Schematic side view showing how a conventional crystal unit is mounted on an external board

Hereinafter, a crystal oscillator will be taken as an example of a piezoelectric vibration device according to an embodiment of the present invention, and will be described with reference to the drawings. FIG. 1 is a schematic cross-sectional view of a crystal resonator according to an embodiment of the present invention, taken along line AA in FIG. FIG. 2 is a schematic top view of the crystal resonator according to the embodiment of the present invention, excluding the lid. FIG. 3 is a schematic top view of the upper plate portion of the container according to the embodiment of the present invention.

As shown in FIGS. 1 and 2, the crystal resonator 1 in this embodiment is a surface-mounted piezoelectric vibration device made up of a substantially rectangular parallelepiped package, and its plan view shape is rectangular. The external dimensions of the crystal oscillator 1 in the present embodiment in a plan view are approximately 1.0 mm in long side and approximately 0.8 mm in short side. It should be noted that the outer dimensions of the crystal resonator in plan view described above are merely examples, and the present invention can be applied to other outer dimensions.

The crystal vibrator 1 is mainly composed of a crystal vibrating piece 2 , a container 3 in which the crystal vibrating piece 2 is housed, and a lid 4 joined to the container 3 . As a specific configuration of the crystal resonator 1, a crystal resonator element is mounted on a pair of mounting pads 6, 6 provided on the upper surfaces of a pair of projections 5, 5 projecting from the inner bottom surface 310 of the recess 7 of the container 3. 2 are cantilevered via conductive adhesives S, S, and then the lid 4 is bonded to the upper surface 320 of the frame-shaped side wall 32 of the container 3 via a sealing material (not shown). ing. By bonding the lid 4 to the container 3, the crystal vibrating piece 2 is hermetically sealed inside the package.

The crystal vibrating piece 2 is an AT-cut crystal vibrating plate, and is rectangular in plan view. As shown in FIGS. 1 and 2, the crystal plate includes a vibrating portion 20 which is a thick region in which an excitation electrode (described later) is formed, and a thin portion 21 which is a region thinner than the vibrating portion 20 around the vibrating portion 20 . It is composed of That is, the cross-sectional shape of the crystal vibrating piece 2 is a "bi-mesa shape" in which the center portions of the front and back main surfaces of the crystal plate protrude. As shown in FIG. 2, the vibrating portion 20 is formed one size smaller than the thin portion 21 in plan view. The external shape of such a crystal plate is formed by using photolithography and wet etching on an AT-cut crystal wafer. The shape of the crystal vibrating piece is not limited to the "bi-mesa shape", and may be, for example, a flat plate shape or an "inverted mesa shape" consisting of a vibrating portion and an outer peripheral portion that is thicker than the vibrating portion. may be In addition, in the present embodiment, an example of using an AT-cut crystal diaphragm as the crystal vibrating piece has been given, but it is not limited to this, and a crystal diaphragm other than an AT-cut crystal diaphragm (for example, a tuning-fork type crystal vibrating plate) is used. A plate or a crystal diaphragm with a cut angle other than AT cut) may be used.

A pair of excitation electrodes 22a and 22b for driving the crystal diaphragm are formed facing each other on the central sides of one main surface of the crystal diaphragm and the other principal surface opposite to the one principal surface. In FIGS. 1 and 2, various electrodes on one main surface side of the crystal diaphragm are denoted by a at the end of the reference numerals, and various electrodes on the other main surface are denoted by b at the end of the reference numerals. The electrodes are distinguished.

Extraction electrodes 23a, 23b are extracted in the same direction from each of the pair of excitation electrodes 22a, 22b. A pair of connection electrodes 241 and 242 are formed on one end side of the quartz plate, which are connected to the ends of the extraction electrodes 23a and 23b and electrically connected to the pair of mounting pads 6 and 6 of the container 3, respectively. .

One of the connection electrodes 241 is partially connected to the connection electrode 241b (see FIG. 1) on the other main surface of the crystal diaphragm via the short-side side surface of the crystal diaphragm on the fixed end side. It is connected to the connection electrode 241a. Similarly, a part of the other connection electrode 242 extends from the connection electrode 242a on one principal surface of the crystal diaphragm to the connection electrode on the other principal surface via the short-side side surface of the quartz crystal diaphragm on the fixed end side. 242b (reference numerals are omitted in FIGS. 1 and 2).

The container 3 is a rectangular container body made of an insulating material as a base material and has a concave portion 7 opening upward. The container 3 is a laminate of a plurality of ceramic green sheets made of an insulating material. Specifically, the container 3 is a sintered ceramic green sheet comprising two layers of a bottom plate portion 30 and an upper plate portion 31 . Incidentally, the number of laminated ceramic green sheets constituting the container may be two or more. The upper plate portion 31 has a frame-shaped side wall 32, and the upper surface 320 of the side wall 32 is a flat surface. A metal film (not shown) is formed in a frame shape on the upper surface 320 of the side wall 32 . The container 3 and the lid 4 are welded via this sealing material.

Internal wiring, which will be described later, is arranged between the lamination of the bottom plate portion 30 and the upper plate portion 31 that constitute the container 3 . In the embodiment of the present invention, the thickness of the bottom plate portion 30 is 0.035 mm or more and 0.055 mm or less. The overall thickness (total height) of the container 3 is 0.18 mm to 0.24 mm.

According to the container according to the embodiment of the present invention, the bottom plate portion has a thickness of 0.035 mm or more and 0.055 mm or less, which is very thin, and the bottom plate portion that is the lowest layer of the container and the upper layer of the bottom plate portion In a low-profile container having an internal wiring disposed therebetween, it is suitable for preventing contact of solder with the end of the lead-out wiring exposed on the outer surface of the container. In addition, when the thickness of the bottom plate portion is 0.035 mm or less, it is not preferable because it becomes difficult to handle in manufacturing the container. On the other hand, when the thickness of the bottom plate portion is 0.055 mm or more, the risk of the solder creeping up and coming into contact with the end portion of the routing wiring is reduced. The thickness of the bottom plate portion is preferably 0.040 mm or more and 0.055 mm or less for application of the present invention.

As shown in FIG. 3, on the inner bottom surface 310 of the recess 7 of the container 3, a pair of protrusions 5, 5 projecting upward from the inner bottom surface 310 are formed at positions spaced inward from the inner wall surface of the side wall 32. It is The pair of protrusions 5, 5 are rectangular in plan view, and are aligned and spaced apart from each other so that their long sides are parallel to the short side direction of the container 3, which is rectangular in plan view. . In addition, in the area of the inner bottom surface 310 of the concave portion 7 of the container 3, a pillow portion 8 having the same height as the pair of protrusions 5, 5 is formed at a position corresponding to the lower side of the free end of the crystal vibrating piece 2. ing.

The projecting portion 5 is made of the same insulating material as the base material of the container 3, and a conductor film is formed on the upper surface thereof. This conductor film serves as a mounting pad 6 and is electrically connected to the crystal vibrating piece 2 via a conductive adhesive S. As shown in FIG. The mounting pads 6 are formed as a pair, and are provided on one side of a pair of opposing sides of the inner bottom surface 310 of the recess 7 of the container 3 . In this embodiment, the mounting pad 6 has a layer structure in which an electrolytic nickel plating layer is formed on a molybdenum metallized layer, and an electrolytic gold plating layer is further laminated thereon. The pillow portion 8 is also made of an insulating material like the protruding portion 5, but no conductive film is formed on the upper surface thereof.

The projecting portion 5 and the pillow portion 8 are molded by pressing a sheet-like molded body before baking with a mold having a predetermined shape. The mold used has a shape in which the portion forming the frame-shaped side wall 32 is recessed and the portion corresponding to the protrusion 5 and the pillow portion 8 is recessed. The container 3 is obtained by sintering the compact after pressurization at a predetermined temperature.

Four external connection terminals 9a, 9b, 9c, and 9d are formed at the four corners of one main surface of the container 3 (the inner bottom surface 310 of the recess 7) and the other main surface (the lower surface 302 of the bottom plate portion 30) on the opposite side. (See Figure 5). In the embodiment of the present invention, the outer peripheral edges of the external connection terminals 9a to 9d extend to the peripheral edge of the outer bottom surface of the container 3 (the lower surface 302 of the bottom plate portion 30), and the outer bottom surface of the container 3 is rectangular in plan view. along each of the long sides and a pair of short sides of the . In other words, the external connection terminals 9 a to 9 d are not formed downward from the peripheral edge of the bottom surface 302 of the bottom plate portion 30 toward the center of the bottom surface 302 of the bottom plate portion 30 .

The external connection terminals 9a to 9d in the embodiment of the present invention are formed by recessing into the base material (bottom plate portion 30) side of the container 3 without protruding downward from the lower surface 302 of the bottom plate portion 30 due to the manufacturing process of the container 3. It is Since the external connection terminals 9a to 9d are recessed into the base material side of the bottom plate portion 30 in this manner, the container is more flexible than a conventional container in which the external connection terminals are formed so as to protrude downward from the bottom surface of the bottom plate portion. The upper end portion of the external connection terminal is positioned above the .

The pair of mounting pads 6, 6 described above includes vias (described later) filled with a conductor in through-holes penetrating through the inside of the pair of protrusions 5, 5 in the thickness direction, and internal wiring between layers (described later). of the four external connection terminals 9a, 9b, 9c, and 9d on the outer bottom surface of the container 3 are electrically connected to obliquely facing two (9b, 9d) respectively. Specifically, the external connection terminal 9b is electrically connected to the other of the pair of mounting pads 6, 6 (lower side in FIG. 3). On the other hand, the external connection terminal 9d is electrically connected to one of the pair of mounting pads 6, 6 (upper side in FIG. 3).

The external connection terminal 9a is a non-connection terminal (NC terminal) that is not connected to any pole. Note that the external connection terminal 9a may be a ground terminal. The external connection terminal 9c is an external connection terminal for grounding, and connects the conductor M on the inner wall surface of one long side of the frame-shaped side wall 32 via the internal wiring (described later) and vias (described later) of the container 3. It is electrically connected to the metal film on the upper surface 320 of the side wall 32 (see FIG. 3). By joining the container 3 to the metal lid 4 via a sealing material, the external connection terminal 9c for grounding is connected to the ground.

In the embodiment of the present invention, the external connection terminals 9a to 9d and the metal film on the upper surface 320 of the side wall 32 also have a configuration in which a nickel plating layer and a gold plating layer are laminated in this order on the molybdenum metallization layer. there is In addition to molybdenum, tungsten (W) or titanium (Ti) may be used for the metallized layer.

The internal wiring and vias of container 3 will now be described in detail with reference to FIGS. FIG. 4 is a schematic top view of the bottom plate portion of the container according to the embodiment of the present invention, and FIG. 5 is a schematic bottom view of the bottom plate portion of the container according to the embodiment of the present invention. FIG. 6 is a perspective view of the bottom plate portion of the container according to the embodiment of the present invention as seen from the upper surface side, and the contours of four external connection terminals are indicated by dashed lines.

As shown in FIG. 3, the pair of mounting pads 6, 6 are connected to the upper surface of the bottom plate portion 30 via a pair of vias V1, V2 (represented by broken lines in FIG. 3) extending downward from each of the mounting pads 6, 6. It is electrically connected to internal wiring (first wiring 11 and second wiring 12) of 301, which will be described later.

The upper end of the via V3 (indicated by a dashed line in FIG. 3) is located on the inner bottom surface 310 of the recess 7 of the container 3. As shown in FIG. The via V3 is finally electrically connected to the external connection terminal 9c through an internal wiring (fourth wiring 14) and a via V7, which will be described later. A metal film (reference numerals are omitted in FIG. 3 and indicated by broken lines) is drawn out horizontally toward the conductor M on the inner wall surface of one long side of the frame-shaped side wall 32 so as to cover the upper end of the via V3. ing. This metal film is connected to the conductor M, and the metal film and the conductor M are covered with an insulating film 10 (alumina coat).

As shown in FIG. 4, the internal wiring in the embodiment of the present invention is composed of four wirings, ie, a first wiring 11, a second wiring 12, a third wiring 13, and a fourth wiring . Hereinafter, the first wiring 11 will be described in order.

The first wiring 11 is electrically connected to the lower end of the via V1 connected to one of the pair of mounting pads 6, 6 (upper side in FIG. 3). The first wiring 11 is connected to the upper end portion of the via V4, and the lower end portion of the via V4 is electrically connected to the external connection terminal 9d on the lower surface 302 of the bottom plate portion 30. As shown in FIG. That is, the first wiring 11 serves as a routing wiring for routing one of the pair of mounting pads 6, 6 provided on one short side of the container 3 to the external connection terminal 9d on the other short side of the container 3. ing.

The first wiring 11 has a portion (first straight line portion 110) extending along the length direction of the long side of the bottom plate portion 30, which is rectangular in plan view, and a portion (first straight line portion 110) branched from the middle of the first straight line portion 110. and a portion (first branch portion 111) extending along the length direction of the side. Both ends 11a and 11b of the first straight portion 110 are exposed on the outer surfaces of each of the pair of short sides of the container 3 which is rectangular in plan view. The terminal end 11c of the first branched portion 111 is exposed on the outer surface of one of the long sides of the container 3 which is rectangular in plan view.

The second wiring 12 is electrically connected to the lower end of the via V2 connected to the other of the pair of mounting pads 6, 6 (lower side in FIG. 3). The second wiring 12 is connected to the upper end portion of the via V5, and the lower end portion of the via V5 is electrically connected to the external connection terminal 9b on the lower surface 302 of the bottom plate portion 30. As shown in FIG. That is, the second wiring 12 is wiring for connecting the other of the pair of mounting pads 6, 6 provided on one short side of the container 3 to the external connection terminal 9b located on the same short side of the container 3. It has become.

The second wiring 12 includes a portion (second straight portion 120) extending along the length direction of the long side of the bottom plate portion 30, which is rectangular in plan view, and a set of portions extending from the end portion of the second straight portion 120 to the bottom plate portion 30. and a portion (first bent portion 121) that bends toward the other long side of the long side. One end portion 12a (one end portion of the second straight portion 120) of the second wiring 12 is exposed on the outer surface of one of the pair of short sides of the container 3 which is rectangular in plan view. The other end portion 12b of the second wiring 12 (terminal end of the first bent portion 121) is exposed on the outer surface of the other long side of the pair of long sides of the container 3 which is rectangular in plan view. The second linear portion 120 and the first linear portion 110 are arranged parallel to each other, and are also arranged parallel to a pair of long sides of the bottom plate portion 30 which is rectangular in plan view.

The third wiring 13 is a wiring connected to an electrically independent external connection terminal 9a that is not connected to any pole. Specifically, the third wiring 13 has a portion (third straight line portion 130) extending along the length direction of the long side of the bottom plate portion 30, which is rectangular in plan view, and the bottom plate portion 30 extending from the end portion of the third straight line portion 130. A portion (second bent portion 131) that bends toward one long side of a pair of long sides. One end portion 13a of the third wiring 13 (terminal end of the second bent portion 131) is exposed to the outer surface of one of the long sides of the container 3 which is rectangular in plan view.

The upper end of the via V6 is connected to the vicinity of the other end of the third wiring 13 . The bottom end of the via V6 is electrically connected to the external connection terminal 9a positioned directly below. In addition, the second bent portion 131 and the first bent portion 121 are positioned on the same straight line in the short side direction of the bottom plate portion 30 .

The fourth wiring 14 is connected to the lower end of the via V3. The lid 4 is ground-connected to the external connection terminal 9c via the via V7 connected to the fourth wiring 14 by bonding the container 3 to the metallic lid 4 via the sealing material. .

The fourth wiring 14 has a portion (fourth linear portion 140 ) extending along the length direction of the long side of the bottom plate portion 30 , which is rectangular in plan view, and a portion (fourth straight portion 140 ) branched from the middle of the fourth straight portion 140 to and a portion (second branch portion 141) extending along the length direction of the side. One end portion 14a (one end portion of the fourth straight portion 140) of the fourth wiring 14 is exposed on the outer surface of the other short side of the pair of short sides of the container 3 which is rectangular in plan view. In addition, the terminal end 14b of the second branch portion 141 is exposed on the outer surface of the other long side of the pair of long sides of the container 3 which is rectangular in plan view. The vicinity of the other end of the fourth linear portion 140 is connected to the lower end of the via V3 described above. Further, the branch point between the fourth straight portion 140 and the second branch portion 141 is connected to the upper end portion of the via V7 electrically connected to the external connection terminal 9c positioned directly below.

The fourth straight portion 140 and the second straight portion 120 are positioned on the same straight line in the longitudinal direction of the container 3 . That is, the fourth straight portion 140 is also arranged parallel to the first straight portion 110 . Also, the first branched portion 111 and the second branched portion 141 are positioned on the same straight line in the short side direction of the container 3 .

As shown in FIG. 4 , in the embodiment of the present invention, the first linear portion 110 is positioned so as to include an imaginary straight line HL passing through the centers of the pair of short sides of the bottom plate portion 30 . That is, the first straight portion 110 is positioned on the virtual straight line HL. Furthermore, the spacing W1 in the short side direction of the bottom plate portion 30 between the first wiring 11 and the third wiring 13 and the spacing W2 in the short side direction of the bottom plate portion 30 between the first wiring and the second wiring are substantially the same. It has become.

In the embodiment of the present invention, the area where the substrate (ceramic) of the bottom plate portion 30 and the substrate (ceramic) of the upper plate portion 31 thereon is in contact with each center of the pair of short sides of the bottom plate portion 30 The positional relationship is substantially symmetrical with respect to the virtual straight line HL passing through. With such a configuration, the joining force between the upper plate portion 31 and the bottom plate portion 30 is made uniform. As a result, warping of the container in the short side direction of the container 3 can be suppressed. Furthermore, in the embodiment of the present invention, the first bent portion 121 and the second bent portion 131 have a substantially line-symmetrical positional relationship with respect to an imaginary straight line VL passing through the centers of the pair of long sides of the bottom plate portion 30. ing. Such a configuration is also effective in suppressing warping of the container 3 in the long side direction.

The lid 4 has a configuration in which a nickel plating layer and a gold plating layer are laminated in this order on the outer peripheral surface of a Kovar base material. A gold-tin alloy (AuSn) is coated in a frame shape on the outer peripheral portion of the surface of the lid 4 that is to be joined to the container 3 . This gold-tin alloy serves as a sealing material, and the container 3 and the lid 4 are welded by heating to a predetermined temperature while the gold-tin alloy and the metal film on the upper surface of the side wall 320 of the container 3 are in contact with each other. be done.

In this embodiment, as the conductive adhesive S, a silicone-based resin adhesive is used. The conductive adhesive S is an adhesive in which a metal filler is contained in a silicone resin, and after application, a curing process is performed in a drying oven controlled to a predetermined temperature profile. As a result, the solvent contained in the adhesive is volatilized, and a conductive path is formed by the metal filler. The application of the present invention is not limited to silicone-based resin adhesives, and other types of resin adhesives may be used.

In the embodiment of the present invention, as shown in FIG. 6, two ends (both ends 11a and 11b of the first straight portion 110) of the routing wiring (first wiring 11) are connected to four external connection terminals 9a to 9d. and do not overlap in planar view transmission. In this way, since both ends 11a and 11b of the first straight portion 110 do not overlap the four external connection terminals 9a to 9d in plan view, even if the amount of solder is larger than the predetermined amount, Even if there is, it is possible to prevent contact of the solder with both ends 11 a and 11 b of the first straight portion 110 exposed on the outer surface of the container 3 . In particular, the solder creeps up to both end portions 11a and 11b of the first straight portion 110, which are end portions of the first wiring 11 that do not overlap the external connection terminal 9d in a plan view, thereby It is possible to prevent electrical continuity between the external connection terminal 9d and the connection terminal 9d. can). As a result, changes in the electrical characteristics of the crystal oscillator 1 can be prevented. It should be noted that the application of the present invention, like the container according to the present embodiment, is such that the external connection terminal is embedded in the base material side of the bottom plate portion, and the thickness of the bottom plate portion is very thin (0.035 mm or more, 0.5 mm). 0.055 mm or less) in the container.

Further, as shown in FIG. 6, according to the container according to the present embodiment, the external wiring corresponding to the other side (the right side in FIG. 6) of the set of opposing sides of the bottom plate portion 30 of the routing wiring (first wiring 11) The area excluding the area overlapping with the connection terminal 9d in plan view is the area between two external connection terminals (between the external connection terminal 9a and the external connection terminal 9b, between the external connection terminal 9c and the external connection terminal 9c) in transmission in plan view. between the connection terminals 9d).

According to the above configuration, even when the amount of solder exceeds the predetermined amount, the ends (11a, 11b) of the lead-out wiring exposed on the outer surface of the container 3 can be connected to the external connection terminals (9a, 9a, 9b). 9b, 9c), it is possible to prevent the solder from contacting the ends (11a, 11b).

-Modified example of the embodiment of the present invention-
Next, a modification of the embodiment of the invention will be described with reference to FIG. FIG. 7 is a perspective view of the bottom plate portion of a container according to a modification of the embodiment of the present invention as seen from the upper surface side, in which outlines of four external connection terminals are indicated by dashed lines. In addition, the same code|symbol is used about the structure similar to embodiment of this invention mentioned above, and the description is omitted. The following description focuses on differences from the above-described embodiment of the present invention.

In the modified example of the embodiment of the present invention, the formation positions of the bent portions of the second wiring and the third wiring are different from the above-described embodiment of the present invention. Specifically, the formation positions of the first bent portion (151) of the second wiring 15 and the second bent portion 161 of the third wiring 16 in the modified example of the embodiment of the present invention are different from those of the above-described present invention. It is shifted to the left with respect to the first bent portion (121) and the second bent portion (131) in the embodiment.

On the upper surface 331 of the bottom plate portion 33 , the second wiring 15 has a portion (second straight portion 150 ) extending along the length direction of the long side of the bottom plate portion 33 which is rectangular in plan view, and an end portion of the second straight portion 150 . and a portion (first bent portion 151) that bends toward the other long side of the pair of long sides of the bottom plate portion 33. As shown in FIG. One end portion 15a of the second wiring 15 (one end portion of the second linear portion 150) is exposed on the outer surface of one of the short sides of the pair of short sides of the bottom plate portion 33 which is rectangular in plan view. The other end portion 15b of the second wiring 15 (terminal end of the first bent portion 151) is exposed on the outer surface of the other long side of the pair of long sides of the bottom plate portion 33 which is rectangular in plan view.

The third wiring 16 is a wiring connected to an electrically independent external connection terminal 9a that is not connected to any pole. One end portion 16a of the third wiring 16 (terminal end of the second bent portion 161) is exposed on the outer surface of one long side of a pair of long sides of the bottom plate portion which is rectangular in plan view. The first bent portion 151 and the second bent portion 161 are positioned on the same straight line in the short-side direction of the bottom plate portion 33, and an imaginary straight line VL passing through the centers of the pair of long sides of the bottom plate portion 33. On the other hand, it is positioned on one of the short sides of the pair of short sides of the bottom plate portion 33 (on the left side in FIG. 7). That is, the first bent portion 151 and the second bent portion 161 are sandwiched between the external connection terminal 9a and the external connection terminal 9d and between the external connection terminal 9b and the external connection terminal 9c in plan view transmission. This region is formed in a state shifted to one side (left side) with respect to the center of the bottom plate portion 33 in the long side direction.

Since the first bent portion 151 is formed at such a position, the other end portion 15b of the second wiring 15 exposed on the outer surface of the container will not be exposed when the amount of solder exceeds the predetermined amount. It is possible to further reduce the risk of a short circuit between the external connection terminals 9b and 9c caused by solder creeping up and contacting the external connection terminals 9c. Similarly, because the second bent portion 161 is formed at such a position, one end of the third wiring 16 exposed on the outer surface of the container is bent when the amount of solder exceeds the predetermined amount. It is possible to further reduce the risk of a short circuit between the external connection terminals 9a and 9d caused by solder creeping up to the portion 16a and contacting the external connection terminals 9d.

In the above-described embodiments and modifications of the present invention, the crystal vibrating piece is conductively bonded to the mounting pad provided on the upper surface of the projection projecting upward from the inner bottom surface of the recess of the container. It may be conductively bonded to a mounting pad that is not provided with a . That is, the container may have a pair of mounting pads formed directly on the inner bottom surface of the concave portion of the container.

In the above-described embodiments and modifications of the present invention, a crystal oscillator was used as an example of a piezoelectric vibration device, but the present invention is not limited to a crystal oscillator, and is a temperature sensor in which a crystal oscillator piece and a temperature sensor are accommodated in a container. It can also be applied to a sensor-embedded crystal unit.

The invention can be embodied in many other forms without departing from its spirit or essential characteristics. Therefore, the above-described embodiments are merely examples in every respect and should not be construed in a restrictive manner. The scope of the present invention is indicated by the claims, and is not restricted by the text of the specification. Furthermore, all modifications and changes within the equivalent scope of claims are within the scope of the present invention.

It can be applied to mass production of piezoelectric vibration devices.

1 crystal oscillator
2 crystal vibrating piece
3 container
4 Lid
6 Mounted pad
9a, 9b, 9c, 9d External connection terminals
11 first wiring
12, 15 second wiring
13, 16 Third wiring
14 fourth wiring

Claims (3)

A container having a substantially rectangular shape in a plan view and containing the piezoelectric vibrating piece,
A pair of mounting pads bonded to the piezoelectric vibrating reed is provided on one side of a pair of opposing sides of one main surface of the container,
The pair of mounting pads are connected to two external connection terminals obliquely opposed among four external connection terminals provided at the four corners of the other main surface of the container on the opposite side of the one main surface via the internal wiring of the container. are connected to the connection terminals,
The internal wiring is routed from one of the pair of mounting pads to an external connection terminal corresponding to the other side of the pair of opposing sides of the two obliquely opposed external connection terminals, and the end of the external connection terminal includes a lead wiring that exposes the part to the outer surface of the container,
at least one end of the routing wiring does not overlap the four external connection terminals in plan view,
The container is a laminate of a plurality of layers made of an insulating material, and at least the internal wiring is arranged between a bottom plate portion that is the lowest layer of the container and an upper layer of the bottom plate portion, and the thickness of the bottom plate portion is is 0.035 mm or more and 0.055 mm or less . A region of the routing wiring excluding a region overlapping in plan view with the external connection terminal corresponding to the other side of the pair of opposing sides is located in a region between two external connection terminals adjacent to each other in plan view transmission. 2. A container according to claim 1, characterized in that: 3. A piezoelectric vibration device in which a piezoelectric vibrating piece is accommodated in the container according to claim 1 or 2, and the piezoelectric vibrating piece is hermetically sealed by bonding a lid to the container.

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