Piezoelectric devices

Abstract

To provide a piezoelectric device that expands the design range of piezoelectric vibrators and electrodes while ensuring sufficient bonding area, thereby enabling miniaturization and improved performance. [Solution] The piezoelectric vibrator has an excitation electrode and a lead electrode extending from the excitation electrode toward the outer periphery formed on its front and back surfaces; a package comprising a rectangular bottom plate in plan view, a wall portion provided along the edge of the bottom plate, and a fixing terminal and a connecting terminal provided in the inner region surrounded by the wall portion; an adhesive for fixing the piezoelectric vibrator to the fixing terminal; and a wire for connecting the lead electrode to the connecting terminal, wherein the piezoelectric vibrator has a notch near the connecting terminal when the fixing terminal is fixed by the adhesive.

Description

Technical Field

[0001] The present disclosure relates to a piezoelectric device, which is a passive element utilizing the piezoelectric effect.

Background Art

[0002] Piezoelectric devices are widely used in various electronic devices such as mobile phones and personal computers, mainly for frequency selection and control. Piezoelectric devices can be classified into piezoelectric vibrators, piezoelectric oscillators, SAW devices, optical devices, etc. according to their functions. Among them, crystal devices such as crystal oscillators and crystal oscillators using crystals as piezoelectric elements, which are passive elements utilizing the piezoelectric effect, are widely known and commonly used.

[0003] As an example of such a crystal device, a crystal oscillator generally has a structure in which a crystal vibrating piece, which is a piezoelectric vibrating piece, is held by a conductive adhesive connected to each of the electrodes formed on its front and back surfaces. Also, different from such a structure, a conductive adhesive for holding is connected to the electrode formed on the back surface of the crystal vibrating piece, and an electrical connection is made to the electrode formed on the front surface of the crystal vibrating piece by wire bonding.

[0004] Patent Document 1 and Patent Document 2 disclose crystal oscillators in which electrical connection is made by such wire bonding. In particular, Patent Document 1 discloses a structure in which a crystal vibrating piece is held by two bumps and electrical connection is made to the surface electrode by wire bonding. Also, Patent Document 2 discloses a structure in which a crystal vibrating piece is held by one bump and electrical connection is made to the surface electrode by wire bonding.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

[0006] To perform wire bonding as described above, it is important to secure an area for wire bonding, and in particular, it is necessary to secure a bonding area for the terminals on the package side. However, in order to secure a bonding area for the terminals on the package side, it is necessary to reduce the dimensions of the quartz crystal and electrodes to take the bonding area into consideration, which limits the design range of the quartz crystal and electrodes, and presents a problem in that it is not possible to adequately meet the demands for miniaturization and performance improvement of the quartz crystal oscillator.

[0007] This disclosure has been made in view of these challenges, and its purpose is to provide a piezoelectric device that can expand the design range of piezoelectric vibrators and electrodes while ensuring bonding area, thereby enabling miniaturization and improved characteristics. [Means for solving the problem]

[0008] According to one aspect of the present disclosure, a piezoelectric device is provided, comprising: a piezoelectric vibrator having an excitation electrode and a lead electrode extending from the excitation electrode toward the outer periphery formed on its front and back surfaces; a package having a rectangular bottom plate in plan view, a wall portion provided along the edge of the bottom plate, and a fixing terminal and a connecting terminal provided in an inner region surrounded by the wall portion; an adhesive for fixing the piezoelectric vibrator to the fixing terminal; and a wire for connecting the lead electrode to the connecting terminal, wherein the piezoelectric vibrator has a notch near the connecting terminal when the fixing terminal is fixed by the adhesive. [Effects of the Invention]

[0009] According to this disclosure, it is possible to provide a piezoelectric device that can expand the design range of piezoelectric vibrators and electrodes while securing bonding area, thereby enabling miniaturization and improved characteristics.

[0010] The effects described above are merely illustrative for the sake of explanation, and the effects relating to this disclosure are not limited to those described above. In addition to the effects described above, any other effects described herein may be achieved. [Brief explanation of the drawing]

[0011] [Figure 1] This is a perspective view of a quartz crystal oscillator according to an embodiment. [Figure 2] Figure 2(a) is a top view showing the internal structure of the quartz crystal oscillator according to the embodiment, and Figure 2(b) is a top view of the package of the quartz crystal oscillator according to the embodiment. [Figure 3] Figure 3(a) is an end view along the dashed line AA in Figure 1, Figure 3(b) is an end view along the dashed line BB in Figure 1, and Figure 3(c) is an end view along the dashed line CC in Figure 3(a). [Figure 4] Figure 4(a) is a surface view of the quartz crystal resonator included in the embodiment, Figure 4(b) is a back view of the quartz crystal resonator included in the embodiment, and Figure 4(c) is a front view of the quartz crystal resonator included in the embodiment. [Figure 5] Figure 5(a) is a plan view of a quartz wafer according to the embodiment, Figure 5(b) is an enlarged view of region R1 in Figure 5(a), and Figure 5(c) is a plan view of the quartz wafer according to the embodiment with electrodes formed on each quartz vibrator. [Figure 6] Figure 6(a) is a surface view showing a modified example of the quartz crystal oscillating element of the quartz crystal oscillator according to the embodiment, Figure 6(b) is a surface view showing another modified example of the quartz crystal oscillating element of the quartz crystal oscillator according to the embodiment, and Figure 6(c) is a surface view showing another modified example of the quartz crystal oscillating element of the quartz crystal oscillator according to the embodiment. [Modes for carrying out the invention]

[0012] Hereinafter, with reference to the drawings, a quartz oscillator, a quartz diaphragm contained therein, and a quartz wafer having a plurality of quartz diaphragms, which are examples of piezoelectric devices of this disclosure, will be described in detail. Note that this disclosure is not limited to the content described below, and can be modified and implemented as such without altering its essence. Furthermore, the drawings used in the embodiments are schematic representations of the quartz oscillator, quartz diaphragm, and quartz wafer related to this disclosure, and have been partially emphasized, enlarged, reduced, or omitted to enhance understanding, and may not accurately represent the scale or shape of each component. In addition, some of the numerical values ​​used in the embodiments are examples only and can be changed as needed. Common components in the drawings are denoted by the same reference numerals.

[0013] <Structure of a quartz crystal oscillator> First, the basic structure of the quartz oscillator and quartz crystal diaphragm according to this disclosure will be described with reference to Figures 1 to 4. Figure 1 is a perspective view of the quartz oscillator according to this embodiment. Figure 2(a) is a top view showing the internal structure of the quartz oscillator according to this embodiment, and Figure 2(b) is a top view of the package of the quartz oscillator according to this embodiment. In particular, Figure 2(a) shows the quartz oscillator with the cover removed, and Figure 2(b) shows the quartz oscillator with both the cover and the quartz crystal diaphragm removed. Furthermore, Figure 3(a) is an end view along the dashed line AA in Figure 1, Figure 3(b) is an end view along the dashed line BB in Figure 1, and Figure 3(c) is an end view along the dashed line CC in Figure 3(a). Finally, Figure 4(a) is a surface view of the quartz crystal diaphragm of the quartz oscillator according to this embodiment, Figure 4(b) is a back view of the quartz crystal diaphragm of the quartz oscillator according to this embodiment, and Figure 4(c) is a front view of the quartz crystal diaphragm of the quartz oscillator according to this embodiment.

[0014] As can be seen from Figures 1, 2(a), and 3(a)-(c), the quartz oscillator 1, an example of a piezoelectric device, has a quartz oscillator package 2 (hereinafter simply referred to as package 2), a quartz crystal 3 mounted in the concave mounting space 2a of package 2, and a metal cover (lid) 4 for sealing the mounting space 2a. The quartz oscillator 1 is a piezoelectric element that can generate a constant frequency due to the piezoelectric phenomenon when a voltage is applied to the quartz crystal 3, which is an example of a piezoelectric crystal.

[0015] Package 2 is a ceramic package formed by stacking multiple ceramics on which a desired metal pattern is formed on the surface. Specifically, Package 2 has a laminated structure in which a bank-shaped wall portion 11 with an opening of a predetermined size and a rectangular bottom plate 12 in plan view are stacked. In particular, the wall portion 11 is provided along the edge of the bottom plate 12. Due to this laminated structure, Package 2 has a mounting space 2a with a recess for mounting the quartz crystal oscillator 3. Furthermore, a region for mounting the quartz crystal oscillator 3 is formed on the surface of the bottom plate 12 in the mounting space 2a, and fixing terminals, which will be described later, are provided inside this region, and connection terminals, which will be described later, are provided around this region.

[0016] Here, the shape of package 2 is a rectangular parallelepiped, and in top view (Figure 2(a)), it is rectangular. In the following, the thickness direction of the crystal oscillator 1 and package 2 is defined as the vertical direction, and the direction perpendicular to this vertical direction is defined as the horizontal direction. Furthermore, the horizontal direction may be distinguished as the long side direction (long side direction) and the short side direction (short side direction) of the crystal oscillator 1 and package 2. In addition, for each component, the surface located on the upper side in the vertical direction may be called the front surface, and the surface located on the lower side may be called the back surface.

[0017] On the exposed surface (the surface located on the upper side in the vertical direction) of the wall portion 11 of the package 2, a conductor pattern 13 for sealing is formed. The planar shape of the conductor pattern 13 is frame-shaped, similar to the wall portion 11. And a cover 4 is joined to the conductor pattern 13 by known metal bonding. Thereby, the mounting space 2a of the package is sealed, and the mounting space 2a is sealed using a gas such as vacuum or nitrogen.

[0018] As shown in FIG. 2(b), on the exposed surface (the surface located on the upper side in the vertical direction) of the bottom plate 12 of the package 2, an adhesive pattern 16 for fixing and power supply of the crystal oscillator 3 and connection terminals 17 for wire bonding are formed. More specifically, the adhesive pattern 16 is composed of a fixing terminal 16a located near one end in the long side direction of the bottom plate 12 and at the central portion in the short side direction, and a wiring pattern 16b extending from the fixing terminal 16a toward the other end in the long side direction. On the other hand, the connection terminals 17 are located at the corners of the bottom plate 12 near the fixing terminal 16a.

[0019] As shown in FIGS. 3(a) and (c), the crystal oscillator 3 is mounted on the fixing terminal 16a via a conductive adhesive 18. That is, the crystal oscillator 3 is fixed at one point by the conductive adhesive 18 applied to the fixing terminal 16a. For this reason, considering the mounting strength and balance of the crystal oscillator 3, etc., the position of the fixing terminal 16a is preferably near one end in the long side direction of the bottom plate 12 and at the central portion in the short side direction, but is not limited thereto as long as the crystal oscillator 3 can be stably fixed. For example, the fixing terminal 16a may be located at the end on the opposite side of the position of the connection terminal 17 in the short side direction. Also, the fixing terminal 16a may be located closer to the central portion of the bottom plate 12 in the long side direction.

[0020] As shown in FIGS. 2(a) and 3(b), (c), a wire 20 is connected to the connection terminal 17 by wire bonding. More specifically, a wedge bond portion 21 formed at one end of the wire 20 is located on the connection terminal 17, and a ball bond portion 22 formed at the other end of the wire 20 is located on the surface side of the crystal oscillator 3. In particular, as shown in FIG. 3(c), the ball bond portion 22 is located above the fixed terminal 16a and the conductive adhesive 18. In other words, the ball bond portion 22 is provided at a position overlapping the fixed terminal 16a, the conductive adhesive 18, and a lead-out electrode to be described later. Thereby, even when a capillary is pressed against the crystal oscillator 3 during ball formation of wire bonding, the crystal oscillator 3 is prevented from being displaced, tilted, or damaged.

[0021] From the viewpoint of making the length of the wire 20 as short as possible, the position of the connection terminal 17 is preferably at a corner of the bottom plate 12 near the fixed terminal 16a, but is not limited thereto. For example, the position of the connection terminal 17 may be closer to the center of the bottom plate 12 in the long side direction and the short side direction. Also, the position of the connection terminal 17 may be at other corners of the bottom plate 12.

[0022] As can be seen from FIGS. 1 and 3(a) to (c), four external connection terminals 25a, 25b, 25c, 25d are formed at the four corners of the back surface of the bottom plate 1 of the package 2. Also, the fixed terminal 16a and the connection terminal 17 are electrically connected to the external connection terminals 25a, 25b, 25c, 25d via a connection wiring (not shown) provided inside the package 2.

[0023] As can be seen from Figures 4(a) to 4(c), the crystal oscillator 3 is formed in a rectangular shape when viewed from above. Furthermore, the crystal oscillator 3 has a notch 3a at one of its four corners. In other words, the crystal oscillator 3 has a shape in which one of its four corners is chamfered when viewed from above. Moreover, as shown in Figure 2(a), the crystal oscillator 3 is mounted so that its long and short sides are aligned with the long and short sides of the crystal oscillator 1. In other words, the long side of the crystal oscillator 3 coincides with the long side of the crystal oscillator 1, and the short side of the crystal oscillator 3 also coincides with the short side of the crystal oscillator 1.

[0024] The crystal oscillator 3 is mounted in the package 2 such that, when the fixing terminal 16a is secured by the conductive adhesive 18, the notch 3a is located near the connection terminal 17. Due to the position of the notch 3a in the mounting space 2a of the package 2, the connection terminal 17 is exposed when the fixing terminal 16a is secured by the conductive adhesive 18. As a result, the capillary is pressed against the exposed connection terminal 17, forming the wedge bond portion 21, which is the connection portion of the wire 20. In other words, the notch 3a exposes the connection portion of the wire 20 at the connection terminal 17.

[0025] For example, if the diameter of the capillary used during wire bonding is 25 μm, and a rectangular quartz crystal without a notch 3a is to be mounted, the dimension required for wire bonding in the long-side direction (i.e., the distance from the inner wall of the wall portion 11 to one end of the short side of the quartz crystal) will be approximately 0.3 mm or more. In contrast, with the quartz crystal 3 according to this embodiment, since wire bonding is performed at the notch 3a, the required dimension can be made smaller than approximately 0.3 mm. In other words, when using a package 2 of the same dimensions, the quartz crystal 3 according to this embodiment can have a larger dimension in the long-side direction compared to a conventional rectangular quartz crystal. Therefore, in order to further reduce the dimension that needs to be secured, a notch 3a is provided to expose the connection terminal 17. That is, the dimensions of the notch 3a can be changed according to the capillary used and adjusted to enable high-precision wire bonding.

[0026] Furthermore, as can be seen from Figures 4(a) to 4(c), electrodes (front electrode 30, back electrode 40) are formed on the front and back surfaces of the quartz crystal vibrator 3, making it possible to apply a voltage to the quartz crystal vibrator 3. Specifically, as can be seen from Figures 4(a) and 4(c), a front electrode 30 is formed on the front surface of the quartz crystal vibrator 3, consisting of an excitation electrode 31 and a lead electrode 32 extending from the excitation electrode 31 toward the outer periphery. On the other hand, as can be seen from Figures 4(b) and 4(c), a back electrode 40 is formed on the back surface of the quartz crystal vibrator 3, consisting of an excitation electrode 41 and a lead electrode 42 extending from the excitation electrode 41 toward the outer periphery.

[0027] Here, the excitation electrode 31 of the surface electrode 30 and the excitation electrode 41 of the back electrode 40 have approximately the same area and are formed to face each other, but this can be appropriately changed to correspond to the electrical characteristics of the quartz oscillator 1. On the other hand, the lead electrode 32 of the surface electrode 30 and the lead electrode 42 of the back electrode 40 are formed to face each other at the ends opposite to the connection portion with the excitation electrodes 31 and 41.

[0028] As can be seen from Figures 2(a) and 4(a), a ball bond portion 22 is placed at the end of the lead electrode 32 of the surface electrode 30, and the wire 20 is connected to it. On the other hand, as can be seen from Figures 3(c) and 4(b), a conductive adhesive 18 is provided at the end of the lead electrode 42 of the back electrode 40, ensuring an electrical connection between the fixed terminal 16a and the lead electrode 42, and the crystal vibrator 3 is fixed to the fixed terminal 16a.

[0029] <Manufacturing method> Next, with reference to Figures 5(a) to 5(c), a method for manufacturing a quartz wafer W consisting of a plurality of quartz resonators 3 and a quartz resonator 1 used in the present disclosure will be described. Here, Figure 5(a) is a plan view of the quartz wafer W according to this embodiment. Figure 5(b) is an enlarged view of region R1 in Figure 5(a). Furthermore, Figure 5(c) is a plan view of the quartz wafer W according to this embodiment with electrodes formed on each quartz resonator 3.

[0030] First, a quartz wafer W with a roughly circular planar shape is prepared, as shown in Figure 5(a). For example, it is a wafer that has been cut from a quartz crystal using the AT cut method. However, the planar shape is not limited to a circle; it may also be square, and the cutting method is not limited to an AT cut; other cuts such as Z cut or SC cut (two-turn cut) may also be used.

[0031] Next, a metal film for forming an etching-resistant mask is formed on both the front and back surfaces of the quartz wafer W. Subsequently, the metal film is processed using a well-known photolithography technique to form an etching-resistant mask on both the front and back surfaces of the quartz wafer W to form the outline of the quartz diaphragm 3. In this embodiment, the etching-resistant mask has a structure that corresponds to a portion corresponding to the outline of the quartz diaphragm 3 including a notch 3a, a frame portion 51 (see Figure 5(b)) formed to surround the multiple quartz diaphragms 3, and a plurality of connecting portions 52 (see Figure 5(b)) that connect the frame portion 51 to each of the quartz diaphragms 3. After that, the quartz wafer W, with the etching-resistant mask formed, is immersed in an etching solution mainly composed of hydrofluoric acid for a predetermined time. Through this process, the portions of the quartz wafer W not covered by the etching-resistant mask are dissolved, and the rough outline of the quartz diaphragm 3 is obtained, as shown in Figure 5(b). Furthermore, the number of connection points 52 to each of the crystal oscillator pieces 3 is not limited to four as shown in Figure 5(b), but may be two, three, five or more, or even just one.

[0032] Next, the etching-resistant mask is removed from the quartz wafer W. At this time, the portions corresponding to the frame 51 and connecting portion 52 of the quartz wafer W are left. This makes it possible to form the outer shape of the quartz diaphragm 3 and to ensure the strength of the frame 51 and connecting portion 52. After that, the quartz wafer W, with a portion of the etching-resistant mask removed, is immersed again in an etching solution mainly composed of hydrofluoric acid for a predetermined time. Here, the predetermined time is the time until the thickness of the area to be formed on the quartz diaphragm 3 reaches a thickness that can meet the required oscillation frequency specifications.

[0033] Next, the etching-resistant mask is removed from the quartz wafer W after the etching described above is completed, exposing the entire surface of the quartz wafer W. Subsequently, metal films for each electrode of the quartz diaphragm 3 are formed on the entire surface (front and back) of the quartz wafer W using a well-known film deposition method. Subsequently, the metal films are patterned into electrode shapes using well-known photolithography and metal etching techniques, and electrodes are formed on the front and back surfaces of the quartz wafer W as shown in Figures 4(a), 4(b), and 5(c). After that, each quartz diaphragm 3 is separated from the frame 51 and individualized by cutting or removing the connection portion 52. This completes the formation of the quartz diaphragm 3 with the electrodes formed.

[0034] The cutting and removal of the connection portion 52 may be performed by etching or mechanically. If performed mechanically, the crystal oscillating element 3 may be subjected to finishing such as etching to remove unnecessary parts.

[0035] (Modified version of the embodiment) In the above embodiment, the shape of the notch 3a was described as having a chamfered corner on the quartz crystal oscillator 3. However, it is not limited to this as long as the connection terminal 17 can be exposed to enable wire bonding. For example, as shown in Figure 6(a), the quartz crystal oscillator 103 may have a shape in which the corner of the quartz crystal oscillator 103 is rounded off as the shape of the notch 103a. By using such rounded chamfering, the cut-out area toward the extraction electrode 32 can be enlarged, making it possible to perform wire bonding with high precision even when using a large-diameter capillary.

[0036] As another modification, as shown in Figure 6(b), the quartz crystal oscillator 203 may have a shape in which the corners of the quartz crystal oscillator 203 are removed in a rectangular shape when viewed from above, as the shape of the notch 203a. This rectangular shape with the corners removed allows for proper exposure of the connection terminal 17, corresponding to the planar shape and position of the lead electrode 32. In other words, it becomes possible to easily expose the connection terminal 17 without being affected by the lead electrode 32.

[0037] As a further modification, as shown in Figure 6(c), the crystal oscillator 303 may have a shape in which a through-hole, which is a rectangular opening in plan view, is formed at the corner of the crystal oscillator 303 as the shape of the notch 303a. Note that the planar shape of the opening is not limited to a rectangle, but may be a circle, an ellipse, or other polygon. By forming the notch 303a with such an opening, the position of the connection terminal 17 can be set at various positions on the bottom plate 12. In other words, the design range of the package 2 can be expanded, the crystal oscillator 1 can be adapted to various designs, and the electrical characteristics can be improved.

[0038] In addition, although in the above embodiment only one wire 20 was used for electrical connection with the surface electrode, multiple wires may be used. In this case, multiple connection terminals 17 may be provided, and the number of notches in the quartz crystal vibrator may also be multiple.

[0039] (Embodiments of this disclosure) A first embodiment of the present disclosure is a piezoelectric device comprising: a piezoelectric vibrator having an excitation electrode and a lead electrode extending from the excitation electrode toward the outer periphery formed on its front and back surfaces; a package having a rectangular bottom plate in plan view, a wall portion provided along the edge of the bottom plate, and a fixing terminal and a connecting terminal provided in an inner region surrounded by the wall portion; an adhesive for fixing the piezoelectric vibrator to the fixing terminal; and a wire for connecting the lead electrode to the connecting terminal, wherein the piezoelectric vibrator has a notch near the connecting terminal when the fixing terminal is fixed by the adhesive. In such a piezoelectric device, the design range of the piezoelectric vibrator and electrodes is expanded while ensuring a bonding area, enabling miniaturization and improved characteristics.

[0040] A second embodiment of the present disclosure is, in the first embodiment, that the notch exposes the wire connection portion of the connecting terminal when the fixing terminal is fixed by the adhesive. This facilitates the wire connection between the connecting terminal and the lead electrode, thereby improving the accuracy of wire bonding.

[0041] A third embodiment of this disclosure is that, in the first or second embodiment, the wire connection portion in the extraction electrode is provided in a position that overlaps with the fixed terminal. This prevents displacement, tilting, and damage to the quartz crystal oscillating element due to wire bonding.

[0042] A fourth embodiment of the present disclosure is that, in any of the first to third embodiments, the fixed terminal is located at one end of the long side and in the center of the short side of the bottom plate, and the connecting terminal is located near the fixed terminal and at a corner of the bottom plate. This improves the mounting accuracy and mounting strength of the crystal diaphragm on the package, and also improves the accuracy of the connection by wire bonding.

[0043] A fifth embodiment of this disclosure is to have only one wire in any of the first to fourth embodiments. This prevents complexity of the wiring inside the crystal oscillator and reduces costs.

[0044] A sixth embodiment of the present disclosure is that, in any of the first to fifth embodiments, the notch has a shape in which the corners of the piezoelectric vibrator are chamfered in plan view. This allows for a larger cutout area toward the lead electrode, making it possible to perform wire bonding with high precision even when using a large-diameter capillary.

[0045] A seventh embodiment of the present disclosure is that, in any of the first to fifth embodiments, the notch has a shape in which the corners of the piezoelectric vibrator are rounded in plan view. This allows for a larger cutout area toward the lead electrode, making it possible to perform wire bonding with high precision even when using a large diameter capillary.

[0046] An eighth embodiment of the present disclosure is that, in any of the first to fifth embodiments, the notch is an opening provided at the corner of the piezoelectric vibrator in a plan view. This allows the position of the connection terminal to be set at various positions on the base plate. In other words, the design range of the package can be broadened, various designs of the quartz oscillator can be accommodated, and the electrical characteristics can be improved. [Explanation of Symbols]

[0047] 1 crystal oscillator 2. Package for crystal oscillator (package) 2a Implementation space 3 Crystal vibrating piece 3a Notch 4 Cover (Lid) 11 Wall 12 Bottom plate 16 bonding patterns 16a fixed terminal 16b Wiring Pattern 17 Connection terminals 18 Conductive adhesive 20 wires 21 Wedge bond section 22 Ball bond section 30 surface electrode 31 Excitation electrode 32 Extraction electrode 40 Backside electrode 41 Excitation electrode 42 Extraction electrode 51 Frame section 52 Connection part W Quartz wafer

Claims

1. A piezoelectric vibrating piece having an excitation electrode and a lead electrode extending from the excitation electrode toward the outer periphery formed on its front and back surfaces, A package comprising a rectangular base plate in plan view, a wall portion provided along the edge of the base plate, and fixing terminals and connection terminals provided in the inner region enclosed by the wall portion, An adhesive for fixing the piezoelectric vibrator to the fixing terminal, The system includes a wire that connects the lead electrode to the connection terminal, The piezoelectric vibrating piece is characterized by having a notch near the connection terminal when the fixing terminal is fixed by the adhesive.

2. The piezoelectric device according to claim 1, characterized in that the notch exposes the wire connection portion of the connection terminal when the fixing terminal is fixed by the adhesive.

3. The piezoelectric device according to claim 1, characterized in that the wire connection portion in the lead electrode is provided at a position that overlaps with the fixed terminal.

4. The aforementioned fixing terminal is located at one end in the long direction and in the center in the short direction of the bottom plate. The piezoelectric device according to claim 1, characterized in that the connection terminal is located near the fixing terminal and at the corner of the bottom plate.

5. The piezoelectric device according to claim 1, characterized in that it has only one of the aforementioned wires.

6. The piezoelectric device according to claim 1, characterized in that the notch portion has a shape in which the corner of the piezoelectric vibrating piece is chamfered in a plan view.

7. The piezoelectric device according to claim 1, characterized in that the notch portion has a shape in which the corners of the piezoelectric vibrating piece are rounded in a plan view.

8. The piezoelectric device according to claim 1, characterized in that the notch is an opening provided at the corner of the piezoelectric vibrator in a plan view.

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