Crystal oscillator and crystal device using the same

Abstract

The present invention provides a 32MHz frequency AT-cut quartz crystal diaphragm with a novel structure that can be housed in a package with an outer diameter of approximately 1.0mm on the long side and approximately 0.8mm on the short side. [Solution] The quartz crystal vibrator 10 comprises a vibrating portion 10a and a peripheral portion 10b that is thinner than the vibrating portion. When the dimension of the quartz crystal vibrator along the X-axis of the quartz crystal is denoted as Lx, the dimension of the quartz crystal vibrator along the Z'-axis of the quartz crystal vibrator as Lz, the dimension of the vibrating portion along the X-axis of the quartz crystal as MSx, and the dimension of the vibrating portion along the Z'-axis of the quartz crystal as MSz, then Lx is in the range of 720 to 736 μm, Lz is in the range of 536 to 552 μm, MSx is in the range of 440 to 460 μm, and MSz is in the range of 438 to 480 μm.

Description

Technical Field

[0001] The present invention relates to a crystal vibrator having a so-called mesa structure in which a vibrating portion is convex, and a crystal device using the same.

Background Art

[0002] As a kind of crystal vibrator that vibrates in a thickness-shear vibration mode, there is a structure in which the vibrating portion of the crystal vibrator is convex compared to other portions. It is a crystal vibrator having a so-called mesa structure. According to this structure, the vibration energy can be efficiently confined in the vibrating portion compared to the case where it is not, so that the characteristics of the crystal vibrator can be improved. As this kind of crystal vibrator, for example, there is one disclosed in Patent Document 1. This crystal vibrator is square in plan view, and includes a vibrating portion, a peripheral portion thinner than this vibrating portion, and excitation electrodes provided on the front and back of the vibrating portion.

[0003] When the dimension along the vibration direction of the thickness-shear vibration of this crystal vibrator is x, the thickness dimension of the vibrating portion is t, the dimension of the vibrating portion along the vibration direction is Mx, the dimension of the excitation electrode along the vibration direction is Ex, and the wavelength of the bending vibration generated along the vibration direction is λ, these x, t, Mx, Ex, and λ are in a predetermined relationship (Claim 1 etc. of Patent Document 1).

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] Quartz crystal vibrators that vibrate in thickness-slip mode come in various frequencies and sizes depending on the application. Moreover, because quartz has delicate physical properties, the structure of a quartz crystal vibrator that can obtain the desired characteristics often differs depending on the frequency and size of the crystal vibrator. Therefore, it is necessary to optimize the structure of each quartz crystal vibrator with different frequencies and sizes. For example, there is a need for a structure that exhibits practical electrical characteristics even for AT-cut quartz crystals used in the frequency band around 32 MHz, which can be housed in a small package with an outer diameter of, for example, a long side dimension of approximately 1.0 mm and a short side dimension of approximately 0.8 mm. This is because AT-cut quartz crystals in the frequency band around 32 MHz are important as reference signal sources for various communication terminal devices such as mobile phones. This application has been made in view of the above points, and therefore the object of this invention is to provide a 32MHz frequency AT-cut quartz diaphragm with a novel structure that can be housed in a small package with an outer diameter of, for example, 1.0mm on the long side and 0.8mm on the short side, and has excellent characteristics, as well as a quartz device using the same. [Means for solving the problem]

[0006] To achieve this objective, according to the first invention of this application, an AT-cut quartz crystal oscillating element having an oscillation frequency of 32 MHz and a rectangular planar shape, comprising a vibrating portion that is square in shape in plan view and a peripheral portion that is thinner than the vibrating portion, When the dimension of the quartz vibrating element along the X-axis is denoted as Lx, the dimension of the quartz vibrating element along the Z'-axis is denoted as Lz, the dimension of the vibrating part along the X-axis is denoted as MSx, and the dimension of the vibrating part along the Z'-axis is denoted as MSz, Lx is 720-736 μm. Lz is 536-552 μm. MSx is 440-460 μm. It is characterized by having an MSz in the range of 438 to 480 μm. In carrying out this first invention, more preferably, Lx is 721-733 μm. Lz is 536-548 μm. MSx is 442-460 μm. A MSz in the range of 438 to 460 μm is preferable. In this invention, 32MHz refers not only to 32MHz itself, but also to frequencies in the vicinity, including frequencies such as 30.32MHz, which are used as reference signal sources for various electronic devices.

[0007] Furthermore, the crystal device, which is the second invention of this application, is characterized by comprising the crystal vibrator of the first invention described above and a container for mounting the crystal vibrator. Furthermore, the term "crystal device" in this second invention includes various types such as a crystal oscillator equipped with the crystal oscillating element of the first invention, a so-called crystal oscillator with a temperature sensor including the crystal oscillating element of the first invention and a temperature sensor (e.g., a thermistor), a crystal oscillator including the crystal oscillating element of the first invention and an oscillation circuit for this crystal oscillating element, and a temperature-compensated crystal oscillator including the crystal oscillating element of the first invention, an oscillation circuit for this crystal oscillating element, a temperature sensor for temperature compensation, and a temperature compensation circuit.

[0008] In carrying out this invention of a crystal device, it is preferable that the container has an outer diameter of 1.0 mm on the long side and 0.8 mm on the short side. This is because it allows for the provision of a small crystal device that meets market demands. The values ​​of 1.0 mm for the long side and 0.8 mm for the short side represent the manufacturing tolerance range of the container, for example, a range of ±0.1 mm for each dimension. Of course, the first and second inventions may also be applied to containers with an outer diameter of larger than 1.0 mm on the long side and 0.8 mm on the short side, such as a container with a long side of 1.2 mm and a short side of 1.0 mm, a container with a long side of 1.6 mm and a short side of 1.2 mm, a container with a long side of 2.0 mm and a short side of 1.6 mm, etc. [Effects of the Invention]

[0009] According to the quartz crystal oscillator and quartz device of this invention, the dimensions Lx along the X-axis of the quartz crystal oscillator, Lz along the Z'-axis of the quartz crystal oscillator, MSx along the X-axis of the quartz crystal in the vibrating part, and MSz along the Z'-axis of the quartz crystal in the vibrating part are set to predetermined ranges. As a result, the variation in the characteristics of the quartz crystal oscillator in response to ambient temperature fluctuations, such as the variation in crystal impedance (CI), can be suppressed to a desired range. Furthermore, a quartz crystal oscillator and quartz device can be realized that can be housed in a small package with an outer diameter of approximately 1.0 mm on the long side and approximately 0.8 mm on the short side. Therefore, it is possible to provide a quartz oscillator with a novel structure that can be housed in a small package and has excellent characteristics, as well as a quartz device using the same. [Brief explanation of the drawing]

[0010] [Figure 1] This is an explanatory diagram of the quartz crystal oscillator 10 and quartz device 30 according to the embodiment. [Figure 2] This figure illustrates a preferred range for the dimensions Lx and Lz of the quartz crystal vibrator of the present invention. [Figure 3] This figure illustrates the preferred ranges for the dimensions MSx and MSz of the vibrating portion (mesa portion) of the quartz crystal vibrator of the present invention. [Figure 4] This figure shows an example of experimental results for determining the optimal range of dimensions Lx and Lz. [Figure 5] This figure follows Figure 4, which shows an example of experimental results for determining the optimal range of dimensions Lx and Lz. [Figure 6] This figure follows Figure 5, which shows an example of experimental results for determining the optimal range of dimensions Lx and Lz. [Figure 7] This figure follows Figure 6, which shows an example of experimental results for determining the optimal range of dimensions Lx and Lz. [Figure 8] Figure 7 is a continuation of Figure 7, illustrating another preferred example of the quartz crystal vibrator of the present invention. [Figure 9] This figure shows an example of experimental results for determining the optimal range of dimensions MSx and MSz. [Figure 10] This figure follows Figure 9, which shows an example of experimental results for determining the optimal range of dimensions MSx and MSz. [Figure 11] It is a diagram for explaining the relationship between the ratio d / t of the step d between the vibrating part and the peripheral part and the thickness t of the vibrating part, and CI. [Figure 12] It is a diagram for explaining another example of the crystal device of the present invention. [Figure 13] It is a diagram for explaining still another example of the crystal device of the present invention.

Embodiments for Carrying Out the Invention

[0011] Hereinafter, embodiments of the crystal vibrating piece and the crystal device of this invention will be described with reference to the drawings. Note that each drawing used in the description only schematically shows the extent to which these inventions can be understood. Also, in each drawing used in the description, the same components are denoted by the same numbers, and the description thereof may be omitted. Further, the shapes, dimensions, materials, etc. described in the following description are merely preferred examples within the scope of this invention. Therefore, the present invention is not limited only to the following embodiments.

[0012] 1. Embodiments of the Crystal Vibrating Piece and the Crystal Device First, the crystal vibrating piece 10 of the embodiment will be described with reference to FIGS. 1(A) and (B). FIG. 1(A) is a plan view of the crystal vibrating piece 10 of the embodiment, and FIG. 1(B) is a cross-sectional view taken along the line P-P in FIG. 1(A) of the crystal vibrating piece 10. The coordinate axes X, Y′, Z′ in FIG. 1 respectively correspond to the crystal axes X, Y′, Z′ of the crystal. Note that Y′ and Z′ mean that they are shifted by a predetermined angle from the Y-axis and Z-axis of the crystal due to the cutting angle of the AT-cut crystal vibrating piece 10.

[0013] The crystal vibrating piece 10 of the embodiment is an AT-cut crystal vibrating piece having an oscillation frequency of 32 MHz and a rectangular planar shape, and includes a vibrating part 10a having a square planar shape, a peripheral part 10b having a thickness thinner than that of the vibrating part 10a, and steps 10c generated on each of the front and back surfaces of the crystal vibrating piece 10 due to the difference in thickness between the vibrating part 10a and the peripheral part 10b. Furthermore, when the dimension of the quartz vibrating element 10 along the X-axis of the quartz is denoted as Lx, the dimension of the quartz vibrating element along the Z'-axis of the quartz is denoted as Lz, the dimension of the vibrating part 10a along the X-axis of the quartz is denoted as MSx, and the dimension of the vibrating part 10a along the Z'-axis of the quartz is denoted as MSz, Lx is 720-736 μm. Lz is 536-552 μm. MSx is 440-460 μm. The MSz is given as 438-480 μm. The reason for specifying this numerical range will be explained later. Furthermore, in the embodiment, the quartz crystal vibrator 10 is defined as having a thickness of t of the vibrating portion 10a, a height of the step between the vibrating portion 10a and the peripheral portion 10b as d, and a ratio of d / t between the two as d / t, where d / t is in the range of 0.06 ≤ d / t ≤ 0.123. The reason for adhering to this numerical range will be explained later. When the heights of the steps on the front and back of the quartz crystal vibrator are defined as d1 and d2 (see Figure 1(B)), d1 and d2 are typically substantially the same and are equal to d. However, d1 and d2 may be different as long as they do not impair the purpose of the present invention. Furthermore, if we define the short side of the crystal oscillating element 10 that is fixed to the container 31 (see Figure 1(C)) housing the crystal oscillating element 1 as the fixed short side 10d, and the short side on the opposite side as the tip short side 10e, then both corners of the tip short side 10e may be rounded or they may be approximately right angles. Approximately right angles are preferable because they allow for a larger surface area of ​​the crystal oscillating element compared to rounded corners.

[0014] The vibrating part 10a has a square shape in plan view, and in this embodiment, it is rectangular. However, the vibrating part 10a may also have a square shape in plan view. The size of the vibrating part 10a and its position relative to the quartz crystal vibrator 10 can be set arbitrarily according to the design of the quartz crystal vibrator 10, and one example will be explained in the experimental results section below. The quartz crystal oscillator 10 is equipped with an excitation electrode 11 and a lead electrode 11a on each of its front and back sides. In this embodiment, the excitation electrode 11 is positioned to fit within the area of ​​the vibrating section 10a and is square in plan view, or rectangular in this embodiment. However, the excitation electrode 11 may be circular or elliptical depending on the design required for the quartz crystal oscillator. The excitation electrode 11 may be larger in plan view than the vibrating section 10a. The size of the excitation electrode 11 and its position relative to the vibrating section 10a can be set arbitrarily according to the design of the quartz crystal oscillator 10, and one example will be explained in the experimental results section below. The lead-out electrode 11a is drawn out from a part of the excitation electrode 11 to the fixed short side 10d of the quartz crystal vibrator 10. The excitation electrode 11 and the lead-out electrode 11a can be made of any suitable metal film. In Figure 1, the convex portion 10x extending downward from the fixed short side 10d of the quartz crystal vibrator 10 is due to the fact that the quartz crystal vibrator 10 is formed in large numbers on a quartz wafer (not shown) using photolithography technology, and is the portion remaining when each quartz crystal vibrator 10 is broken off from the quartz wafer. The convex portion 10x is not essential, but it can contribute to improving the adhesive strength when fixing the quartz crystal vibrator 10 to the container 31 with conductive adhesive 33.

[0015] Next, the crystal device 30 of the embodiment will be described, mainly with reference to Figures 1(C) and (D). Figure 1(C) is a plan view of the crystal device 30 of the embodiment, and Figure 1(D) is a side view of the crystal device 30. The crystal device 30 of this embodiment is an example of a crystal oscillator 30 comprising a container 31, a conductive adhesive 33, a lid member 35, and the crystal vibrator 10 described above. The container 31 comprises a rectangular recess 31a in plan view that can enclose the quartz crystal oscillator 10, a rim 31b surrounding the recess 31a, a connection pad 31c provided on a part of the bottom surface of the recess 31a, and an external connection terminal 31d provided on the outer bottom surface of the container 31. The quartz crystal oscillator 10 is connected and fixed to the connection pad 31c by a conductive adhesive 33. The connection pad 31c is connected to the external connection terminal 31d by via wiring or the like (not shown). This container 31 can be made of, for example, a known ceramic package.

[0016] The quartz crystal oscillator 10 is mounted in the recess 31a of the container 31. Specifically, the quartz crystal oscillator 10 is connected and fixed to the connection pad 31c of the container 31 by conductive adhesive 33 at the position of the lead electrode 11a on the fixed short side 10d. Therefore, the quartz crystal oscillator 10 is fixed to the container 31 in a so-called cantilever support structure. A lid member 35 is attached to the bank portion 31b of the container 31 by an arbitrary suitable sealing method. As a result, the quartz crystal vibrator 10 is sealed in an airtight state inside the container 31. The recess 31a of the container 31 is in a reduced-pressure atmosphere, a nitrogen atmosphere, or an inert gas atmosphere.

[0017] 2. Experiments and Simulations 2-1. About Lx and Lz Next, we will explain the dimensions Lx and Lz of the quartz crystal oscillator 10 as asserted in this invention. The inventor of this application fabricated multiple levels of quartz vibrating elements by varying the dimension Lx along the X-axis of the quartz crystal in multiple levels within the range of 720 to 740 μm, and the dimension Lz along the Z'-axis of the quartz crystal in multiple levels within the range of 536 to 559 μm (see Figure 2). However, during these multiple prototypes, the dimensions MSx and MSz of the vibrating part 10a were set to MSx = 455 μm and MSz = 441 μm. The reason for setting MSx and MSz to these dimensions is that they are values ​​near the center of the preferred range for MSx and MSz, as determined in experiments described later in which the dimensions MSx and MSz were varied (see Figure 3). Furthermore, the positions of the vibrating section 10a and the excitation electrode 11 relative to the quartz crystal vibrator 10 were such that the planar center point α of the vibrating section 10a and the excitation electrode 11 (see Figure 1(C)) were offset by approximately 47 μm in the direction toward the tip of the quartz crystal vibrator 10 relative to the planar center point β of the quartz crystal vibrator 10 (see Figure 1(C)). Note that the distance between point α and point β (the so-called offset value) was set to approximately 47 μm, but this is just an example and can be changed according to the design.

[0018] Using the quartz crystal oscillator fabricated under these conditions, a quartz crystal oscillator 30 with the structure shown in Figure 1(C), which is an example of a quartz device, was prototyped. Next, the degree of variation in crystal impedance (CI) of each of the fabricated quartz oscillators 30 with respect to ambient temperature, i.e., the temperature characteristics of CI, were measured. The measurement temperature range was -40 to 125°C, and the measurement temperature step was set to 1°C. Based on these measurement results, we investigated the preferred ranges for Lx and Lz. Figure 2 summarizes the results, with the horizontal axis representing dimension Lz and the vertical axis representing dimension Lx. A "○" indicates that the temperature characteristics of the prototype quartz oscillator CI were good and met the standard R (see Figure 4 onwards), a "△" indicates that it was partially outside the standard R but still within a practical range, and a "×" indicates that it was outside the standard R.

[0019] Furthermore, Figures 4, 5, 6, and 7 show the specific CI temperature characteristics of several prototypes with different dimensions Lx and Lz, as shown in Figure 2. In all of Figures 4 through 7, the horizontal axis represents temperature and the vertical axis represents CI (normalized value). In Figures 4 through 7, the dashed box labeled R represents the preferred CI standard. In Figures 4 through 7, there are multiple samples (specifically 30) for each level, and the temperature characteristics of these multiple CIs were actually measured. However, the worst (labeled Max) and best (labeled Min) CI temperature characteristics within each group are shown as representative examples to illustrate the general trend of each prototype's quality. Specifically, the relationship between Figure 2 and Figures 4-7 is as follows: The characteristics shown in Figure 4(A) correspond to the upper left region of the distribution shown in Figure 2, the characteristics shown in Figure 4(B) correspond to the upper right region of the distribution shown in Figure 2, the characteristics shown in Figure 5(A) correspond to the central left region of the distribution shown in Figure 2, the characteristics shown in Figure 5(B) correspond to the central right region of the distribution shown in Figure 2, the characteristics shown in Figure 6(A) correspond to the central region of the distribution shown in Figure 2, the characteristics shown in Figure 6(B) correspond to the slightly lower right region of the distribution shown in Figure 2, the characteristics shown in Figure 7(A) correspond to the lower left region of the distribution shown in Figure 2, and the characteristics shown in Figure 7(B) correspond to the lower right region of the distribution shown in Figure 2. Based on the characteristics illustrated in Figures 4 to 7 and the evaluations of ○, △, and × shown in Figure 2, it can be said that the dimensions Lx and Lz of the quartz crystal oscillator are good when Lx is 720 to 736 μm and Lz is 536 to 552 μm, and more preferably when Lx is 721 to 733 μm and Lz is 536 to 548 μm.

[0020] 2-2. About MSx and MSz Next, we will explain the dimensions MSx and MSz of the vibrating part 10a as claimed in this invention. The inventor of this application fabricated several quartz vibrating pieces by varying the dimension MSx along the X-axis of the quartz crystal in the vibrating part 10a at multiple levels in the range of 440 to 525 μm, and the dimension MSz along the Z'-axis of the quartz crystal at multiple levels in the range of 420 to 500 μm (see Figure 3). However, during the fabrication of these multiple prototypes, the dimensions Lx and Lz of the quartz vibrating piece 10 were set to Lx = 727 μm and Lz = 542 μm. The reason for setting Lx and Lz to these dimensions is that they are values ​​near the center of the preferred range of dimensions Lx and Lz (see Figure 2) that was found in the above-mentioned experiments in which dimensions Lx and Lz were varied. Furthermore, the positions of the vibrating section 10a and the excitation electrode 11 relative to the quartz crystal vibrator 10 were such that the planar center points α (see Figure 1(C)) of the vibrating section 10a and the excitation electrode 11, respectively, were offset by 47 μm in the direction of the tip of the quartz crystal vibrator 10 relative to the planar center point β (see Figure 1(C)) of the quartz crystal vibrator 10. Of course, the offset value of 47 μm is just an example and can be changed according to the design.

[0021] Using the quartz crystal oscillator fabricated under these conditions, a quartz crystal oscillator 30 with the structure shown in Figure 1(C), which is an example of a quartz device, was prototyped. Next, the degree of variation in crystal impedance (CI) of each of the fabricated quartz oscillators 30 with respect to ambient temperature, i.e., the temperature characteristics of CI, were measured. The measurement temperature range was -40 to 125°C, and the measurement temperature step was set to 1°C. Based on these measurement results, we examined the preferred ranges for MSx and MSz. Figure 3 summarizes the results, with the horizontal axis representing dimension MSz and the vertical axis representing dimension MSx. A "○" indicates that the temperature characteristics of the prototype quartz oscillator CI were good and met the standard R (see Figure 4 onwards), a "△" indicates that it was partially outside the standard R but still within a practical range, and a "×" indicates that it was outside the standard R.

[0022] Furthermore, Figures 8, 9, and 10 show the specific CI temperature characteristics of some of the prototypes with dimensions MSx and MSz shown in Figure 3. In all of Figures 8 to 10, the horizontal axis represents temperature and the vertical axis represents CI (normalized value). In Figures 8 to 10, the dashed box labeled R represents the preferred CI standard. In Figures 8 to 10, there are multiple samples (specifically 30) for each level, and the temperature characteristics of multiple CIs have actually been measured. However, the worst (labeled Max) and best (labeled Min) CI temperature characteristics within each prototype group are shown as representative examples to illustrate the general trend of each prototype's quality. Furthermore, the relationship between Figure 3 and Figures 8 to 10 is as follows: The characteristics shown in Figure 8(A) correspond to the leftmost region of the distribution shown in Figure 3, the characteristics shown in Figure 8(B) correspond to the upwardly protruding region of the distribution shown in Figure 3, the characteristics shown in Figure 9(A) correspond to the central region of the distribution shown in Figure 3, the characteristics shown in Figure 9(B) correspond to the central right region of the distribution shown in Figure 3, and the characteristics shown in Figure 10 correspond to the rightmost region of the distribution shown in Figure 3. Based on the characteristics illustrated in Figures 8 to 10 and the evaluations of ○, △, and × shown in Figure 3, it can be said that the dimensions MSx and MSz are preferably in the range of MSx 440 to 460 μm and MSz 438 to 480 μm, and more preferably in the range of MSx 442 to 460 μm and MSz 438 to 460 μm.

[0023] 2-3. Regarding the height d of the step and the thickness t of the quartz crystal vibrator The preferred range of d / t was analyzed using the finite element method. The analysis was performed by creating multiple analysis models in which the step height d was varied in 1 μm steps between 2 μm and 8 μm, using a model of the quartz crystal oscillator 10 shown in Figure 1(A) with Lx=727 μm, Lz=542 μm, MSx=455 μm, and MSz=441 μm, and extracting the CI (crystal impedance) for each model. In this case, the oscillating frequency of the quartz crystal oscillator 10 is 32 MHz, so the thickness of the vibrating part 10a is 48.4 μm. Therefore, the d / t values ​​for each model are approximately 0.041, 0.061, 0.082, 0.103, 0.123, 0.144, and 0.165. Figure 11 shows the relationship between d / t on the horizontal axis and the relative CI value of each model with respect to a reference value on the vertical axis. From Figure 11, it can be seen that CI decreases as the step size increases, and that CI reaches its lowest value between d / t of approximately 0.06 and 0.12. However, as the step size increases further (d / t increases), CI begins to increase. The reason why CI increases when d / t exceeds 0.12 is presumed to be due to the influence of unwanted vibrations. If we set the upper limit of the CI standard to 0.9 in terms of the relative CI value, then from Figure 11, we can see that a d / t of 0.06 ≤ d / t ≤ 0.123 is preferable.

[0024] In the above-described embodiments, the X dimension, Z' dimension of each of the vibrating portion and the exciting electrode, and the positions of the vibrating portion and the exciting electrode with respect to the crystal vibrating piece are shown in one example. However, even if they are not the above examples, the effects of the present invention can be obtained. That is, the X dimension, Z' dimension of each of the vibrating portion and the exciting electrode, and the positions of the vibrating portion and the exciting electrode with respect to the crystal vibrating piece can be changed within a range that does not impair the object of the present invention. Also, in the above-described embodiments, an example using a container having a recess as the container is shown. However, the container may be a container composed of a flat base and a cap-shaped lid member capable of enclosing the crystal vibrating piece.

[0025] Also, in the above, an example of the crystal oscillator 30 as the crystal device has been described. However, as shown in the plan view of FIG. 12(A) and the side view of FIG. 12(B), a crystal device 37 including the crystal vibrating piece 10 and further other functional components 39 may be used. Specifically, it may be a so-called crystal oscillator with a temperature sensor including the crystal vibrating piece 10 of the present invention and a temperature sensor (for example, a thermistor) as the other functional component 39. Further, the other functional component 39 may be a crystal oscillator in which an oscillation circuit for the crystal vibrating piece 10 is provided. Further, the other functional component 39 may be a temperature-compensated crystal oscillator or the like in which an oscillation circuit for the crystal vibrating piece of the present invention, a temperature sensor for temperature compensation, and a temperature compensation circuit are included as an IC or the like. Also, FIG. 12 shows an example of a structure in which the crystal vibrating piece 10 and the functional component 39 are mounted in one room. However, as shown in the cross-sectional view of FIG. 13, a structure in which the crystal vibrating piece 10 and the functional component 39 are mounted in separate rooms, which has a so-called H-shaped structure when viewed in cross-section, may also be used.

Explanation of Reference Numerals

[0026] 10: Crystal vibrating piece of the embodiment 10a: Vibrating portion 10b: Peripheral portion 10c: Step 10d: Fixed-side short side 10e: Tip-side short side 10x: Convex portion 11: Exciting electrode 11a: Lead-out electrode 30: Crystal device of the embodiment 31: Container 31a: recess 31b: embankment 31c: Adhesive pad 31d: External connection terminal 33: Conductive adhesive 35: Lid material 37: Crystal devices of other embodiments 39: Functional components

Claims

1. A quartz crystal oscillator with an oscillation frequency of 32 MHz and a rectangular planar shape, comprising a square vibrating portion in plan view and a peripheral portion that is thinner than the vibrating portion, When the dimension of the quartz vibrating element along the X-axis is denoted as Lx, the dimension of the quartz vibrating element along the Z'-axis is denoted as Lz, the dimension of the vibrating part along the X-axis is denoted as MSx, and the dimension of the vibrating part along the Z'-axis is denoted as MSz, Lx is 720-736 μm. Lz is 536-552 μm. MSx is 440-460 μm. A quartz crystal oscillator characterized by having an MSz in the range of 438 to 480 μm.

2. A quartz crystal oscillator with an oscillation frequency of 32 MHz and a rectangular planar shape, comprising a square vibrating portion in plan view and a peripheral portion that is thinner than the vibrating portion, When the dimension of the quartz vibrating element along the X-axis is denoted as Lx, the dimension of the quartz vibrating element along the Z'-axis is denoted as Lz, the dimension of the vibrating part along the X-axis is denoted as MSx, and the dimension of the vibrating part along the Z'-axis is denoted as MSz, Lx is 721-733 μm. Lz is 536-548 μm. MSx is 442-460 μm. A quartz crystal oscillator characterized by having an MSz in the range of 438 to 460 μm. That's good.

3. The crystal vibrating piece according to claim 1 or 2, characterized in that when the thickness of the vibrating part is defined as t and the height of the step difference between the vibrating part and the peripheral part is defined as d, d / t is in the range of 0.06 ≤ d / t ≤ 0.

123.

4. A quartz device comprising a quartz crystal vibrator as described in claim 1 and a container enclosing the quartz crystal vibrator.

5. A crystal device characterized by comprising a crystal vibrator as described in claim 1, a temperature sensor, and a container enclosing these.

6. A crystal device characterized by comprising a crystal oscillator according to claim 1, an oscillation circuit thereof, a temperature sensor, a temperature compensation circuit, and a container containing these.

7. A quartz device comprising a quartz crystal vibrator as described in claim 3 and a container enclosing the quartz crystal vibrator.

8. A crystal device comprising a crystal vibrator as described in claim 3, a temperature sensor, and a container enclosing these.

9. A crystal device characterized by comprising a crystal oscillator according to claim 3, an oscillation circuit thereof, a temperature sensor, a temperature compensation circuit, and a container containing these.

10. The crystal device according to any one of claims 4 to 6, characterized in that the container is rectangular in shape when viewed from above, and its external dimensions are such that the long side dimension is 1.0 mm and the short side dimension is 0.8 mm.

11. The crystal device according to any one of claims 4 to 6, characterized in that the container is rectangular in shape when viewed from above, and its external dimensions are such that the long side dimension is 1.2 mm and the short side dimension is 1.0 mm.

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