JP7363180B2 - Container and piezoelectric device using the container - Google Patents

Description

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

A surface-mounted crystal resonator, which is a small and thin piezoelectric device, has the following configuration, for example. That is, one short side of the crystal vibrating piece, which is rectangular in plan view, is cantilever-bonded via a conductive adhesive to a pair of electrode pads provided on the inner bottom surface of the recess of the container, and then surrounds the recess. The lid is connected to the upper surface of the side wall via a sealing material. Crystal resonators having such a configuration are disclosed, for example, in Patent Documents 1 and 2.

JP2001-77656 Utility Model Publication No. 5-25827

In the crystal resonator configured as described above, the crystal vibrating piece is cantilevered onto a pair of electrode pads at both ends of one short side of the crystal vibrating piece, that is, at two points. In automotive and other applications where bonding reliability is required, it is necessary to improve the bonding strength by bonding the free end side of the crystal vibrating piece with a conductive adhesive.

When the free end side of the crystal vibrating piece is also bonded to the container with a conductive adhesive, there is a method of fixing the center part of the side of the free end side with a conductive adhesive. That is, when the crystal vibrating piece is joined to the container at three points as a whole, as in the conventional example shown in FIG. A pillow 16 is formed at the position by tungsten metallization, and a conductive adhesive S1 is applied to the upper surface of the pillow 16. In addition, in FIG. 6, for convenience of explanation, the lid is removed so that the inside can be viewed.

A pair of electrode pads 5a and 5b are formed by metallization, and a pair of bumps 6a and 6b are laminated on the upper surface of each of them by metallization. This is to ensure a vertical distance (gap) between the lower surface of the crystal vibrating piece 2 processed into a biconvex lens shape and the inner bottom surface of the recess 17. In order to support the crystal vibrating piece 2 horizontally with respect to the inner bottom surface of the recess 17, the pillow 16 is placed on the lower layer 16a so that the thickness approaches the sum of the thickness of the pair of electrode pads 5a, 5b and the pair of bumps 6a, 6b. It is composed of two metallized layers: and an upper layer 16b. Note that the surface of the upper layer 16b of the pillow is not plated with gold or the like.

In the container 30 shown in FIG. 6, before the crystal vibrating piece 2 is mounted on the container 30, a conductive adhesive (S, S1) is applied in advance to the pair of bumps 6a, 6b and the upper layer 16b of the pillow 16. It is necessary to keep it. However, since the outermost layer of the pillow 16 is tungsten, the conductive adhesive S1 applied to the upper layer 16b of the pillow 16 becomes the same color as tungsten during the binarization process in image recognition. There is a problem in that it becomes difficult to inspect the state of application of S1 to the pillow 16 (application diameter, application position). Furthermore, depending on variations in the application of the conductive adhesive S1 to the upper layer 16b of the pillow 16, there is a possibility that the conductive adhesive S1 may be applied at a position shifted from the position corresponding to the free end side of the crystal vibrating piece 2. There is,
There is a possibility that it will be difficult to reliably join the free end side of the crystal vibrating piece 2. This also applies when both ends of the free end side of the crystal vibrating piece 2 are fixed with the conductive adhesive S1 (when the crystal vibrating piece is joined to the container at four points in total).

The present invention has been made in view of these points, and provides a container and a container that can reliably inspect the applied state of conductive adhesive by image recognition and improve the bonding strength between the crystal vibrating piece and the container. The object of the present invention is to provide a piezoelectric device using the container.

To achieve the above object, the invention of claim 1 provides electrode pads at the four corners of a substantially rectangular mounting section in a plan view in which a piezoelectric vibrating piece is accommodated, and the electrode pads are connected to a set of short sections of the mounting section. It consists of a first electrode pad and a second electrode pad provided on one side of the side, and a third electrode pad and a fourth electrode pad provided on the other side of the pair of short sides of the mounting part, The first electrode pad is electrically connected to the third electrode pad via a first wiring extending from the first electrode pad in the long side direction of the mounting part, and the third electrode pad is electrically connected to the third electrode pad. three electrode pads , the first electrode pad, the third electrode pad, and the fourth electrode pad; The container is characterized in that the outermost layer of the container is plated .

According to the above invention, the first electrode pad is electrically connected to the third electrode pad via the first wiring extending from the first electrode pad in the long side direction of the mounting portion. The third electrode pad is electrically connected to the fourth electrode pad via a second wiring extending from the third electrode pad in the short side direction of the mounting portion. That is, among the four electrode pads, three electrode pads, the first electrode pad, the third electrode pad, and the fourth electrode pad, are electrically connected by one pole. Since the three electrode pads of the same polarity are electrically connected in succession in this way, the outermost layer of these three electrode pads can be plated (for example, gold plated). As a result, for example, the third electrode pad and/or the fourth electrode pad and the conductive adhesive applied to the electrode pad do not become the same color during image recognition, and the application state of the conductive adhesive can be checked. It can be reliably inspected by image recognition means.

Further, according to the above invention, in addition to the first electrode pad and the second electrode pad, one or both of the third electrode pad and the fourth electrode pad are mechanically connected via the piezoelectric vibrating piece and the conductive adhesive. can be connected to. Thereby, the bonding strength between the piezoelectric vibrating piece and the container can be improved.

In order to achieve the above object, the invention of claim 2 provides that the first to fourth electrode pads of the container according to claim 1 are arranged evenly at the four corners of the mounting portion which is substantially rectangular in plan view, and has a rectangular shape in plan view. In a state in which the piezoelectric vibrating piece is bonded to at least the first to third electrode pads via a conductive adhesive, a center point of the piezoelectric vibrating piece in a plan view and a center point of the mounting portion in a plan view are This piezoelectric device is characterized by substantially matching.

According to the above invention, when the first to fourth electrode pads are evenly arranged at the four corners of the mounting portion which is substantially rectangular in plan view, and the piezoelectric vibrating piece is joined to the container, the piezoelectric vibrating piece is The center point in , and the center point in a plan view of the mounting section substantially coincide with each other. Due to this positional relationship, when stress is propagated to the piezoelectric device bonded to the external substrate with solder or the like, the first to fourth electrode pads are evenly arranged at the four corners of the mounting section, which is approximately rectangular in plan view. This can alleviate the imbalance in stress transmitted to the container. Furthermore, since the center point of the piezoelectric vibrating piece in plan view and the center point of the mounting portion in plan view substantially match, the piezoelectric vibrating piece and the container are joined to each other in a symmetrical state. The stress propagating from the aforementioned external substrate to the container can be made uniform.

Further, in order to achieve the above object, the invention of claim 3 provides a piezoelectric vibrating piece having a pair of excitation electrodes formed facing each other on its front and back main surfaces, which is electrically bonded to the electrode pad of the container according to claim 1. In the state where they are bonded via a bonding agent, the second wiring and the second electrode pad extend in the long side direction of the mounting section, and the length in the long side direction is equal to the length of the long side of the mounting section. Further, the third wiring, which is less than half the length of each of the second electrode pad and the fourth electrode pad, excluding the length in the long side direction of the mounting portion, is exposed to the piezoelectric vibration in a transparent plan view. The piezoelectric device is characterized in that it is formed in a region of the piece at a position that does not overlap with the pair of excitation electrodes.

According to the above invention, the second wiring and the third wiring are formed in a transparent area of the piezoelectric vibrating piece in a plan view and at a position that does not overlap with the pair of excitation electrodes, thereby making it possible to generate piezoelectric vibrations. In a state where the piece is joined to the container via the conductive adhesive, the second wiring and the third wiring do not protrude from the periphery of the piezoelectric vibrating piece when viewed from above. Further, the third wiring extends from the second electrode pad in the long side direction of the mounting section, and the length in the long side direction is equal to the length of the long side of the mounting section. By being less than half the length of each of the fourth electrode pads excluding the length in the long side direction of the mounting portion, for example, the base material of the inner bottom surface of the recess of the container is sufficiently exposed from the periphery of the piezoelectric vibrating piece. Therefore, during the binarization process in image recognition, the piezoelectric vibrating piece and the second wiring and the third wiring do not become the same color, and the boundary between the piezoelectric vibrating piece and the base material of the inner bottom surface of the recess can be clearly recognized. be able to. Thereby, the outline of the piezoelectric vibrating piece joined to the container can be reliably recognized by the image recognition means. As a result, the mounting state of the piezoelectric vibrating piece can be reliably inspected.

Further, according to the above invention, since the second wiring and the third wiring are formed at positions that do not overlap with the pair of excitation electrodes, there is a gap between the excitation electrode and the second wiring and between the excitation electrode and the third wiring. It is possible to prevent stray capacitance from occurring. This makes it possible to prevent fluctuations in the oscillation frequency due to changes in capacitance.

As described above, according to the present invention, there is provided a container capable of reliably inspecting the applied state of conductive adhesive by image recognition and improving the bonding strength between the crystal vibrating piece and the container, and the container. A piezoelectric device using the present invention can be provided.

A schematic cross-sectional diagram of a crystal resonator according to an embodiment of the present invention A schematic top view of a crystal resonator according to an embodiment of the present invention with the lid removed A schematic top view of a container according to an embodiment of the present invention A schematic bottom view of a container according to an embodiment of the present invention A schematic top view of a crystal resonator according to another example of the embodiment of the present invention, excluding the lid Schematic top view of a conventional crystal resonator with the lid removed

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a crystal resonator will be exemplified as a piezoelectric device according to an embodiment of the present invention, and a description will be given with reference to the drawings. FIG. 1 is a schematic cross-sectional view taken along line AA in FIG. 2 of a crystal resonator according to an embodiment of the present invention. FIG. 2 is a schematic top view of the crystal resonator according to the embodiment of the present invention with the lid removed.

As shown in FIGS. 1 and 2, the crystal resonator 1 in this embodiment is a surface-mounted piezoelectric device consisting of a substantially rectangular parallelepiped package, and its shape in plan view is substantially rectangular. The external dimensions of the crystal resonator 1 in this embodiment in a plan view are approximately 2.5 mm on the long side and approximately 2.0 mm on the short side. Note that the external dimensions of the crystal resonator described above in plan view are merely examples, and the present invention is applicable to other external dimensions.

The main components of the crystal resonator 1 are a container 3 in which the crystal resonator piece 2 is housed, and a lid 4 joined to the container 3. Specifically, three of the electrode pads (5a, 5b, 5c) provided at the four corners of the mounting portion 10 of the container 3, which is substantially rectangular in plan view, are provided with crystal vibrating pieces 2 that are rectangular in plan view. After being bonded via a conductive adhesive S, the lid 4 is bonded to the upper surface 320 of the frame portion 32 of the container 3 via a sealing material G.

The crystal vibrating piece 2 is an AT-cut crystal vibrating plate, and has a substantially rectangular shape when viewed from above. As shown in FIGS. 1 and 2, the crystal diaphragm is machined so that its thickness gradually decreases from the central portion toward the outer peripheral edge (so-called bevel processing). Note that the shape of the crystal vibrating piece is not limited to such a beveled shape, but may be a flat plate or a shape consisting of a vibrating part and an outer peripheral part that is thicker than the vibrating part. It may be a "reverse mesa shape" or a "mesa shape" consisting of a vibrating part and an outer peripheral part formed thinner than the vibrating part. Further, in this embodiment, an example is given in which an AT-cut crystal diaphragm is used as the crystal vibrating piece, but the invention is not limited to this, and a crystal diaphragm having a cutting angle other than the AT-cut crystal may be used. .

A pair of excitation electrodes 22a and 22b for driving the crystal diaphragm are formed facing each other on the center side of one main surface of the quartz diaphragm and the other main surface opposite to the one main surface. In addition, in FIGS. 1 and 2, a is added to the end of the code for various electrodes on one main surface side of the crystal diaphragm, and b is added to the end of the code for various electrodes on the other main surface side. Differentiate between electrodes.

Extracting electrodes 23a, 23b are formed from each of the pair of excitation electrodes 22a, 22b, which are pulled out in the same direction. A pair of connection electrodes 241 and 242 are formed on one end of the crystal diaphragm to be connected to the terminal ends of the extraction electrodes 23a and 23b and to be conductively joined to electrode pads (described later) of the container 3, respectively.

One of the connection electrodes 241 has a part extending from the connection electrode 241b (the reference numeral is omitted in FIG. 2) on the other main surface of the crystal diaphragm to the short side surface on one end side of the crystal diaphragm (the left side in FIGS. 1 and 2). It is connected to the connection electrode 241a on one principal surface via. Similarly, a part of the other connection electrode 242 passes from the connection electrode 242a on one main surface of the crystal diaphragm to the short side surface on the one end side of the crystal diaphragm, and the connection electrode 242b on the other main surface ( (see Figure 1).

The container 3 is a rectangular container body in plan view made of an insulating material as a base material, and is provided with a recess 11 that opens upward. The container 3 is a laminate of a plurality of ceramic green sheets. Specifically, as shown in FIG. 1, the container 3 is a fired body of ceramic green sheets consisting of two layers, a bottom plate part 31 and a frame part 32. Note that the number of laminated ceramic green sheets constituting the container may be two or more. The upper surface 320 of the frame portion 32 is a flat surface. The lid 4 is bonded to the upper surface 320 of this frame portion 32 via a sealing material G made of a glass material.

As shown in FIG. 3, the mounting portion 10 of the container 3 is approximately rectangular in plan view, and electrode pads 5a, 5b, 5c, and 5d are formed at its four corners. Specifically, a first electrode pad 5a and a second electrode pad 5b are formed on one side (left side in FIG. 2) of a pair of short sides of the mounting section 10, which is approximately rectangular in plan view. A third electrode pad 5c and a fourth electrode pad 5d are formed on the other short side of the pair (right side in FIG. 2). These four electrode pads 5a, 5b, 5c, and 5d are equally arranged at the four corners of the mounting portion 10, which is substantially rectangular in plan view. The first electrode pad 5a, the second electrode pad 5b, the third electrode pad 5c, and the fourth electrode pad 5d are connected to a virtual center line that passes through the center point O1 of the mounting section 10 in a plan view and extends in the short side direction of the container 3. It is line symmetrical with respect to CL1. Further, the first electrode pad 5a and the third electrode pad 5c, the second electrode pad 5b and the fourth electrode pad 5d are located at a virtual center extending in the long side direction of the container 3 through the center point O1 in a plan view of the mounting section 10. It is also symmetrical with respect to line CL2. Furthermore, the first electrode pad 5a and the fourth electrode pad 5d have a point-symmetrical positional relationship with respect to the center point O1 of the mounting section 10 in a plan view. Similarly, the second electrode pad 5b and the third electrode pad 5c have a point-symmetrical positional relationship with respect to the center point O1 of the mounting section 10 in a plan view. In addition, in this embodiment, the center point of the container 3 in plan view also substantially coincides with the above-mentioned O1.

The first electrode pad 5a is electrically connected to one excitation electrode (22b) of the pair of excitation electrodes 22a, 22b of the crystal vibrating piece 2. On the other hand, the second electrode pad 5b is electrically connected to the other excitation electrode (22a) of the pair of excitation electrodes 22a, 22b of the crystal vibrating piece 2 (see FIG. 2).

The first electrode pad 5a is electrically connected to the third electrode pad 5c via a first wiring 7 extending from the first electrode pad 5a in the long side direction (left-right direction in FIG. 3) of the mounting section 10. . The third electrode pad 5c is electrically connected to the fourth electrode pad 5d via a second wiring 8 extending from the third electrode pad 5c in the short side direction (vertical direction in FIG. 3) of the mounting section 10. There is. On the other hand, the second electrode pad 5b is electrically connected to the third wiring 9.

According to the above configuration, among the four electrode pads, three electrode pads, the first electrode pad 5a, the third electrode pad 5c, and the fourth electrode pad 5d, are electrically connected by one pole. Since the three electrode pads (5a, 5c, 5d) of the same polarity are electrically connected in succession in this way, the outermost layer of these three electrode pads (5a, 5c, 5d) is plated ( For example, gold plating) can be applied. As a result, for example, the third electrode pad 5c and/or the fourth electrode pad 5d and the conductive adhesive S applied to the electrode pad do not become the same color during image recognition, and the conductive adhesive S The application state of the coating can be reliably inspected by image recognition means.

Further, according to the above configuration, in addition to the first electrode pad 5a and the second electrode pad 5b, the third electrode pad 5c can also be mechanically connected to the crystal vibrating piece 2 via the conductive adhesive S. . Thereby, the bonding strength between the crystal vibrating piece 2 and the container 3 can be improved. In this embodiment, the crystal vibrating piece 2 is joined to the container 3 at three points: the first electrode pad 5a, the second electrode pad 5b, and the third electrode pad 5c. The crystal vibrating piece 2 may be joined to the container 3 at four points including the fourth electrode pad 5d.

In this embodiment, the first to fourth electrode pads 5a to 5d are metalized layers of tungsten. Bumps 6a to 6d made of tungsten are formed on each of the first to fourth electrode pads 5a to 5d. The bumps 6a to 6d are formed to be one size smaller than the first to fourth electrode pads 5a to 5d in plan view, and are arranged evenly on each of the first to fourth electrode pads 5a to 5d in plan view. It is located in The bumps 6a to 6d are arranged between the crystal vibrating piece 2 and the inner bottom surface of the recess 11 so that the thick portion of the beveled crystal vibrating piece 2 (approximately the center of the crystal vibrating piece) does not come into contact with the inner bottom surface of the recess 11. The pads are stacked on each of the first to fourth electrode pads 5a to 5d to ensure a gap between them.

In this embodiment, an electrolytic nickel plating layer is formed to cover the surfaces of the first to fourth electrode pads 5a to 5d and the bumps 6a to 6d laminated on these electrode pads, and an electrolytic nickel plating layer is further formed on the surface of the bumps 6a to 6d stacked on these electrode pads. Plating layers are laminated. Note that, depending on the frequency of the crystal vibrating piece, the crystal vibrating piece may not be beveled, so the bumps 6a to 6d do not necessarily need to be formed on the electrode pads.

The third wiring 9 electrically connected to the second electrode pad 5b extends from the second electrode pad 5b in the long side direction of the mounting section 10 (the left-right direction in FIG. 3), and its tip is connected to the frame 3 of the container 3. It is bent at right angles in the direction toward the long side (downward in FIG. 3). Here, the length L1 of the third wiring 9 in the long side direction (horizontal direction in FIG. 3) of the mounting section 10 is calculated from the length L of the long side of the mounting section 10 between the second electrode pad 5b and the fourth electrode pad 5d. It is less than half of the length L2 excluding the length (W, W) in the long side direction of each mounting portion 10. A part of the bent portion of the third wiring 9 (internal wiring 90) is hidden between the laminated layers of the bottom plate part 31 and the frame part 32, and the castellation CA2 ( (described later).

The first wiring 7 extending from the first electrode pad 5a in the long side direction of the mounting section 10 (the left-right direction in FIG. ) branches at right angles. A part of the branched first wiring 7 (internal wiring 70) is inserted between the laminated layers of the bottom plate part 31 and the frame part 32, and a castellation CA1 (described later) is provided on the side wall of the long side of the frame part 32. ) is electrically connected to the

The first electrode pad 5a is electrically connected to an internal wiring 71 extending in a direction toward the short side portion of the frame portion 32 (leftward in FIG. 3). The third electrode pad 5c is electrically connected to an internal wiring 72 extending in a direction toward the short side portion of the frame portion 32 (rightward in FIG. 3).

The internal wirings 70, 71, 72, and 90 described above are electrically connected to internal wirings 70, 71, 72, and 90 of other containers adjacent in a matrix. Specifically, in two vertically and horizontally adjacent containers, internal wiring 71 and internal wiring 72 are electrically connected, and internal wiring 70 and internal wiring 90 are electrically connected via castellations CA1 and CA2. be done. In this way, a large number of containers 3, 3, . . . , 3 are electrically connected vertically and horizontally. In other words, the internal wirings 70, 71, 72, and 90 are wirings (plating lines) used for electrolytic plating.

As shown in FIG. 4, a pair of external connection terminals 12a and 12b are formed on one main surface (the inner bottom surface of the recess 11) of the bottom plate 31 of the container 3 and the other main surface on the opposite side (the lower surface of the bottom plate 31). has been done. In the embodiment of the present invention, the external connection terminals 12a and 12b are substantially rectangular in plan view, and their longitudinal direction is arranged along the long side direction of the outer bottom surface (lower surface of the bottom plate portion 31) of the substantially rectangular container 3 in plan view. has been done. A pair of bumps 13a and 13b are formed on each of the pair of external connection terminals 12a and 12b. The bumps 13a, 13b are formed to be one size smaller than the external connection terminals 12a, 12b in plan view.

The pair of external connection terminals 12a, 12b are electrically connected to castellations CA1, CA2 formed on the outer surface of a pair of long sides of the container 3, which is substantially rectangular in plan view. Specifically, the external connection terminal 12a is electrically connected to the castellation CA1, and the external connection terminal 12b is electrically connected to the castellation CA2. Here, the castellation is a metal film coated on the inner wall surface of a through hole formed in a semi-elliptical shape in a plan view through a part of the outer surface of the bottom plate part 31 and the frame part 32.

In the embodiment of the present invention, the external connection terminals 12a and 12b have a structure in which a nickel plating layer and a gold plating layer are laminated in this order on a tungsten metallized layer. In addition to tungsten, molybdenum (Mo) or titanium (Ti) may be used for the metallized layer.

The lid 4 is a flat lid made of ceramic. On the main surface of the lid 4 on the side to be joined to the container 3, a frame-shaped sealing material G made of a glass material is formed along the periphery thereof. When the sealing material G and the upper surface 320 of the frame 32 of the container 3 are heated to a predetermined temperature while in contact with each other, the sealing material G melts and spreads over the upper surface 320 of the frame 32 . Thereby, the container 3 and the lid 4 are joined.

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

As shown in FIG. 2, in this embodiment, the crystal vibrating piece 2 is electrically connected to three electrode pads, a first electrode pad 5a, a second electrode pad 5b, and a third electrode pad 5c, via a conductive adhesive S. is joined to. Specifically, the three corners of the crystal vibrating piece 2, which is rectangular in plan view, are coated with conductive adhesives S, S, They are electrically connected via S. In the state in which the crystal vibrating piece 2 is joined to the container 3 in this way, the center point O2 of the crystal vibrating piece 2 in plan view and the center point O1 of the mounting section 10 in plan view (see FIG. 3) substantially coincide with each other. It is in a state.

According to the above configuration, the first to fourth electrode pads 5a to 5d are evenly arranged at the four corners of the mounting portion 10, which is substantially rectangular in plan view, and when the crystal vibrating piece 2 is joined to the container 3, The center point O2 of the crystal vibrating piece 2 in a plan view and the center point O1 of the mounting section 10 in a plan view substantially match. Due to this positional relationship, the first to fourth electrode pads 5a to 5d are evenly arranged at the four corners of the mounting section 10 when stress is propagated to the crystal resonator bonded to the external board by soldering or the like. This makes it possible to alleviate the imbalance in stress transmitted to the container 3. Further, in the embodiment of the present invention, the center point O2 of the crystal vibrating piece 2 in a plan view and the center point O1 of the mounting section 10 in a plan view substantially match. That is, the crystal vibrating piece 2 and the container 3 are line symmetrical with respect to the virtual center line CL1, and are also line symmetrical with respect to the virtual center line CL2. As a result, the crystal vibrating piece 2 and the container 3 are joined to each other in a symmetrical state, so that the stress propagating from the external substrate to the container 3 can be made uniform. As a result, the stress propagating to the crystal resonator piece through the container can be reduced, so that changes in the characteristics of the crystal resonator can be suppressed.

In the crystal resonator according to the embodiment of the present invention, the crystal resonator piece 2 is connected to the second wiring 8 while being bonded to the first to third electrode pads 5a to 5c of the container 3 via the conductive adhesive S. , extends from the second electrode pad 5b in the long side direction of the mounting section 10, and the length L1 in the long side direction is from the length L of the long side of the mounting section 10, the second electrode pad 5b and the fourth electrode pad The third wiring 9, which is less than half of the length L2 excluding the length (W, W) in the long side direction of each mounting portion 10 of 5d, is within the area of the crystal vibrating piece 2 in a plan view. It is formed at a position that does not overlap with the pair of excitation electrodes 22a and 22b.

As shown in the example shown in FIG. If the second wiring 14 overlaps in plan view, it becomes difficult to recognize the outline of the crystal vibrating piece 2 in the binarized image for shape recognition of the crystal vibrating piece 2 after being bonded to the container 33. I end up. Further, in a state where the crystal vibrating piece 2 is bonded to the first to third electrode pads 5a to 5c of the container 33 via the conductive adhesive S, the length L3 of the third wiring 15 in the long side direction of the mounting portion 10 is is the length L2 obtained by subtracting the length (W, W) of each of the second electrode pad 5b and fourth electrode pad 5d in the long side direction of the mounting portion 10 from the length (L) of the long side of the mounting portion. If it occupies most of the area, the exposed area of the substrate on the inner bottom surface of the recess 11 becomes minute, making it difficult to recognize the outline of the crystal vibrating piece 2. Please note that the mounting condition of the crystal vibrating piece bonded to the container via conductive adhesive (specifically, the mounting angle of the crystal vibrating piece on the mounting part, and the distance between the side of the crystal vibrating piece and the inner wall of the frame) When inspecting the distance), at least one long side and at least one short side of the crystal vibrating piece, which is rectangular in plan view, are used as references.

On the other hand, in the configuration shown in FIG. 2, the second wiring 8 and the third wiring 9 are within the area of the crystal vibrating piece 2 in a plan view and do not overlap with the pair of excitation electrodes 22a and 22b. By forming the crystal vibrating piece 2 at the position shown in FIG. It never sticks out. Further, in this embodiment, the third wiring 9 extends from the second electrode pad 5b in the long side direction of the mounting section 10, and the length L1 in the long side direction is from the length L of the long side of the mounting section 10. , the length W of each of the second electrode pad 5b and the fourth electrode pad 5d in the long side direction of the mounting portion 10 is less than half of the length L2 excluding W. In other words, the portion of the third wiring 9 extending in the long side direction of the mounting portion 10 does not extend beyond the virtual center line CL1 to the fourth electrode pad 5d side. With this configuration, the base material of the inner bottom surface of the recess 11 of the container 3 is sufficiently exposed from the periphery of the crystal vibrating piece 2, so that the crystal vibrating piece 2 and the second wiring 8 are exposed during the binarization process in image recognition. The boundary between the crystal vibrating piece 2 and the substrate of the inner bottom surface of the recess 11 can be clearly recognized without the third wiring 9 becoming the same color. Thereby, the outline of the crystal vibrating piece 2 joined to the container 3 can be reliably recognized by the image recognition means. As a result, the mounting state of the crystal vibrating piece 2 can be reliably inspected.

Further, according to the configuration shown in FIG. 2, since the second wiring 8 and the third wiring 9 are formed at positions that do not overlap with one of the excitation electrodes 22b, there is a gap between one of the excitation electrodes 22b and the second wiring 8. Furthermore, generation of stray capacitance between one excitation electrode 22b and the third wiring 9 can be prevented. This makes it possible to prevent fluctuations in the oscillation frequency due to changes in capacitance.

In the embodiment of the present invention described above, a crystal resonator was used as an example of a piezoelectric device, but the present invention is not limited to a crystal resonator, but is applicable to a crystal resonator with a built-in temperature sensor in which a crystal resonator piece and a temperature sensor are housed in a container. It can also be applied to oscillators and crystal oscillators.

The invention may be embodied in other forms without departing from its spirit or essential characteristics. Therefore, the above-described embodiments are merely illustrative in every respect, and should not be interpreted in a limiting manner. The scope of the present invention is indicated by the claims, and is not restricted in any way by the main text of the specification. Furthermore, all modifications and changes that come within the scope of equivalents of the claims are intended to be within the scope of the present invention.

It can be applied to mass production of piezoelectric devices.

1 Crystal resonator 2 Crystal resonator piece 3 Container 4 Lid 5a, 5b, 5c, 5d Electrode pads 6a, 6b, 6c, 6d Bump 7 First wiring 8 Second wiring 9 Third wiring 10 Mounting part 11 Recessed parts 12a, 12b External Connection terminals 13a, 13b bump

Claims (3)

Electrode pads are provided at the four corners of the mounting section, which is approximately rectangular in plan view and accommodates the piezoelectric vibrating piece.
The electrode pads include a first electrode pad and a second electrode pad provided on one side of the set of short sides of the mounting section, and a third electrode pad provided on the other side of the set of short sides of the mounting section. Consisting of an electrode pad and a fourth electrode pad,
The first electrode pad is electrically connected to the third electrode pad via a first wiring extending from the first electrode pad in the long side direction of the mounting part,
The third electrode pad is electrically connected to the fourth electrode pad via a second wiring extending from the third electrode pad in the short side direction of the mounting portion ,
A container characterized in that the outermost layer of three electrode pads, the first electrode pad, the third electrode pad, and the fourth electrode pad, is plated. The first to fourth electrode pads of the container according to claim 1 are arranged evenly at the four corners of the mounting portion, which is substantially rectangular in plan view, and the piezoelectric vibrating piece, which is rectangular in plan view, is arranged on at least the first to third electrode pads. A piezoelectric device, wherein a center point of the piezoelectric vibrating piece in a plan view and a center point of the mounting portion in a plan view substantially coincide with each other in a state where they are bonded via a conductive adhesive. In a state in which a piezoelectric vibrating piece having a pair of excitation electrodes facing each other on its front and back main surfaces is joined to the electrode pad of the container according to claim 1 via a conductive adhesive,
the second wiring;
Each of the second electrode pad and the fourth electrode pad extends from the second electrode pad in the long side direction of the mounting part, and the length in the long side direction is from the length of the long side of the mounting part. A third wiring whose length is less than half of the length excluding the length in the long side direction of the mounting part,
A piezoelectric device, characterized in that it is formed in a transparent area of the piezoelectric vibrating piece in a plan view and at a position that does not overlap with the pair of excitation electrodes.

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