JP2011211441A - Manufacturing method of piezoelectric oscillator, piezoelectric oscillator, oscillator, electronic device, and electric wave clock - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing method of a piezoelectric oscillator that can shorten a frequency adjustment time, a piezoelectric oscillator, an oscillator, an electronic device and an electric wave clock.SOLUTION: The manufacturing method of the piezoelectric oscillator has a fine adjustment step (S80). In the step, a piezoelectric oscillation piece formed of a layered metallic film that has a coarse and fine adjustment film and a fine adjustment film for frequency adjustment at an oscillation arm is sealed in a package, the coarse and fine adjustment film and the fine adjustment film are partially removed by being irradiated with laser light, and the frequency of the piezoelectric oscillation piece is adjusted so as to be a target frequency. The fine adjustment step (S80) has a frequency measurement step (S81) which measures a frequency of the piezoelectric oscillation piece, and a pattern processing step (S83) which radiates laser light with a preset processing pattern and removes at least the coarse and fine adjustment film at a time in accordance with a difference between the frequency measured by the frequency measurement step (S81) and the target frequency.

Description

  The present invention relates to a method for manufacturing a piezoelectric vibrator, a piezoelectric vibrator, an oscillator, an electronic device, and a radio timepiece.

  For example, a cellular phone or a portable information terminal often uses a piezoelectric vibrator using quartz or the like as a time source, a timing source such as a control signal, or a reference signal source. As this type of piezoelectric vibrator, there is one in which a tuning fork type crystal vibrating piece is vacuum-sealed in a package in which a cavity (sealed chamber) is formed. The package has a structure in which the concave portion functions as a cavity by overlapping each other in a state where the concave portion is formed on one of the pair of glass substrates and directly bonding the two.

As a frequency adjustment method in the case of manufacturing the piezoelectric vibrator configured as described above, a weight part such as Cr, Au, Ag or the like is formed in advance on the arm tip of the tuning-fork type crystal vibrating piece, and laser light is irradiated to this weight part. Then, there is a method of partially removing (trimming) (for example, see Patent Document 1).
More specifically, before vacuum-sealing the tuning fork type crystal vibrating piece in the package, the weight part is irradiated with a laser beam to remove the tuning fork type crystal resonator, and the tuning fork type quartz crystal in the package is adjusted. There is a fine adjustment process in which the vibrator is vacuum-sealed, and is removed by irradiating the weight portion with laser light from the outside of the package, and adjusted to a target frequency.

In the coarse adjustment step and the fine adjustment step, the frequency of the tuning fork type quartz vibrating piece is measured, and the weight portion is irradiated with laser light based on the measurement result and removed. Then, these operations are repeated several times in the coarse adjustment step, and then further several times in the fine adjustment step, so that the frequency of the tuning fork type crystal vibrating piece gradually falls within the target frequency range.
In the coarse adjustment process and the fine adjustment process, a plurality of piezoelectric vibrators are arranged on the production line from the viewpoint of production efficiency, and the frequency is often adjusted collectively. In this case, since the laser beam scans the production line, there is a limit to the amount of the weight part that can be removed at one time. For this reason, in the coarse adjustment process and the fine adjustment process, frequency measurement and removal work (trimming work) using laser light are repeated.

JP 2009-207186 A

However, in the above-described prior art, the tuning fork type crystal resonator is vacuum-sealed in the package after the coarse adjustment process, and the fine adjustment process is performed, so the number of processes for adjusting the frequency However, there is a problem that it takes time.
In addition to this, in the coarse adjustment process and the fine adjustment process, the frequency measurement and the removal work (trimming work) using laser light are repeated, so that it takes more time to adjust to the target frequency.

  Accordingly, the present invention has been made in view of the above-described circumstances, and provides a method of manufacturing a piezoelectric vibrator, a piezoelectric vibrator, an oscillator, an electronic device, and a radio timepiece that can shorten the time for adjusting the frequency. Is.

  In order to solve the above problems, a piezoelectric vibrator manufacturing method according to the present invention includes a tuning fork type piezoelectric vibration in which a coarse and fine tuning film for frequency adjustment and a weight metal film made of a fine tuning film are formed on a vibrating arm. The tuning fork type piezoelectric vibrating piece is formed by sealing a piece in a package and partially removing the coarse / fine adjustment film and the fine adjustment film by irradiating the coarse / fine adjustment film with laser light. A method of manufacturing a piezoelectric vibrator having a fine tuning step of adjusting the frequency of the tuning fork to have a target frequency, wherein the fine tuning step includes a frequency measuring step of measuring a frequency of the tuning fork type piezoelectric vibrating piece, and the frequency measuring step. A pattern processing step of irradiating the laser beam with a preset processing pattern in accordance with a difference between the frequency measured by the above and the target frequency, and removing at least the rough and fine-tuning film at one time. To.

  With this configuration, it is possible to remove a desired amount of the coarse / fine adjustment film and the fine adjustment film at a time according to the difference between the measured frequency and the target frequency. For this reason, the number of processes can be reduced, and the time for adjusting the frequency can be shortened.

  The method for manufacturing a piezoelectric vibrator according to the present invention is characterized in that the processing pattern is set so as to remove the coarse and fine adjustment film and the fine adjustment film at the same processing timing by the laser beam.

  With this configuration, the amount of film to be removed based on the processing pattern can be set with high accuracy. For this reason, it can be approximated to a target frequency at a stretch in one process, and also the time for adjusting the frequency can be shortened.

  In the method of manufacturing a piezoelectric vibrator according to the present invention, the processing pattern is set so that the rough fine-tuning film and a portion of the fine-tuning film removed by the laser beam have at least one spot. Features.

  By comprising in this way, each film | membrane can be removed with high precision compared with the case where each film | membrane is removed in a line form. For this reason, the frequency | count of the frequency measurement process in a fine adjustment process can be reduced, and also it becomes possible to shorten the time which adjusts a frequency.

  In the method for manufacturing a piezoelectric vibrator according to the present invention, the processing pattern includes a plurality of spots in which the coarse / fine adjustment film and portions of the fine adjustment film removed by the laser beam are spaced apart from each other. It is set so that it may form.

  With such a configuration, each film can be removed with higher accuracy, so that the time for adjusting the frequency can be further shortened.

  In the piezoelectric vibrator manufacturing method according to the present invention, the pattern processing step includes a rough adjustment step performed in a previous step of sealing a tuning fork type piezoelectric vibrating piece in the package, and the rough adjustment step includes: The step of removing the coarse / fine adjustment film by the laser light, wherein the rough adjustment pattern of the coarse / fine adjustment film in the coarse adjustment step is set in the processing pattern.

  By comprising in this way, the rough adjustment process performed at the front process which seals a tuning fork type piezoelectric vibrating piece in a package can be deleted. For this reason, it is possible to further reduce the time for adjusting the frequency.

In the piezoelectric vibrator according to the present invention, a tuning fork type piezoelectric vibrating piece is sealed in a package, and a coarse metal film for frequency adjustment and a weight metal film made of a fine tuning film are formed on a vibrating arm portion of the tuning fork type piezoelectric vibrating piece. In the piezoelectric vibrator in which a removal portion is partially formed by irradiating the coarse and fine adjustment film and the fine adjustment film with a laser beam, a spot is formed on at least a part of the removal portion. It is characterized by.
In this case, it is desirable that the removal portion is composed of a plurality of spots formed at intervals.

  With this configuration, it is possible to provide a piezoelectric vibrator capable of shortening the time for adjusting the frequency.

  An oscillator according to the present invention is characterized in that the piezoelectric vibrator according to claim 6 or 7 is electrically connected to an integrated circuit as an oscillator.

  With this configuration, it is possible to provide an oscillator that has excellent vibration characteristics and can reduce the number of assembly steps.

  An electronic apparatus according to the present invention is characterized in that the piezoelectric vibrator according to claim 6 or 7 is electrically connected to a timer unit.

  By comprising in this way, the electronic device which is excellent in a vibration characteristic and can shorten an assembly man-hour can be provided.

  A radio timepiece according to the present invention is characterized in that the piezoelectric vibrator according to claim 6 or 7 is electrically connected to a filter portion.

  By comprising in this way, the radio timepiece which is excellent in a vibration characteristic and can shorten an assembly man-hour can be provided.

  According to the present invention, it is possible to remove a desired amount of the coarse / fine adjustment film and the fine adjustment film in one step at a time according to the difference between the measured frequency and the target frequency. For this reason, the number of processes can be reduced, and the time for adjusting the frequency can be shortened.

1 is an external perspective view of a piezoelectric vibrator in an embodiment of the present invention. It is an internal block diagram of the piezoelectric vibrator in embodiment of this invention, Comprising: The state which removed the lid board | substrate is shown. It is sectional drawing which follows the AA line of FIG. It is a disassembled perspective view of the piezoelectric vibrator in the embodiment of the present invention. It is a top view of the piezoelectric vibrating piece in the embodiment of the present invention. It is a bottom view of the piezoelectric vibrating piece in the embodiment of the present invention. It is sectional drawing which follows the BB line of FIG. 3 is a flowchart showing a method for manufacturing a piezoelectric vibrator in an embodiment of the present invention. It is a flowchart which shows the piezoelectric vibrating reed manufacturing process in embodiment of this invention. It is a disassembled perspective view of the wafer bonded body in the embodiment of the present invention. It is process drawing which shows the manufacturing method of the piezoelectric vibrator in embodiment of this invention. It is process drawing which shows the manufacturing method of the piezoelectric vibrator in embodiment of this invention. It is process drawing which shows the manufacturing method of the piezoelectric vibrator in embodiment of this invention. It is process drawing which shows the manufacturing method of the piezoelectric vibrator in the modification of embodiment of this invention. It is a schematic block diagram of the oscillator in embodiment of this invention. It is a schematic block diagram of the portable information device in embodiment of this invention. It is a schematic block diagram of the radio timepiece in the embodiment of the present invention.

(Piezoelectric vibrator)
Next, an embodiment of the present invention will be described with reference to FIGS.
FIG. 1 is an external perspective view of a piezoelectric vibrator 1 according to an embodiment of the present invention. FIG. 2 is an internal configuration diagram of the piezoelectric vibrator 1 and shows a state where a lid substrate 3 is removed. 3 is a cross-sectional view taken along line AA in FIG. 2, and FIG. 4 is an exploded perspective view of the piezoelectric vibrator 1. As shown in FIG.

  As shown in FIGS. 1 to 4, the piezoelectric vibrator 1 of the present embodiment has a box-shaped package 5 that is laminated in two layers of a base substrate 2 and a lid substrate 3, and a cavity inside the package 5. A surface mount type piezoelectric vibrator in which a piezoelectric vibrating piece 4 is sealed in C. In FIG. 4, the excitation electrode 15, the extraction electrodes 19 and 20, the mount electrodes 16 and 17, and the weight metal film 21, which will be described later, are omitted for easy understanding of the drawing.

5 is a top view of the piezoelectric vibrating piece 4 constituting the piezoelectric vibrator 1, FIG. 6 is a bottom view of the piezoelectric vibrating piece 4, and FIG. 7 is a cross-sectional view taken along line BB in FIG.
As shown in FIGS. 5 to 7, the piezoelectric vibrating reed 4 vibrates when a predetermined voltage is applied, and is a tuning fork type formed of a piezoelectric material such as quartz, lithium tantalate, or lithium niobate. The piezoelectric plate 24 is provided.

The piezoelectric plate 24 includes a pair of vibrating arm portions 10 and 11 arranged in parallel, and a base portion 12 that integrally fixes the base end sides of the pair of vibrating arm portions 10 and 11. Further, on the outer surface of the pair of vibrating arm portions 10 and 11, an excitation electrode 15 including a first excitation electrode 13 and a second excitation electrode 14 that vibrate the pair of vibrating arm portions 10 and 11, Mount electrodes 16 and 17 electrically connected to the first excitation electrode 13 and the second excitation electrode 14 are provided.
The piezoelectric plate 24 has grooves 18 formed on both main surfaces of the pair of vibrating arm portions 10 and 11 along the longitudinal direction of the vibrating arm portions 10 and 11. The groove portion 18 is formed from the proximal end side of the vibrating arm portions 10 and 11 to approximately the middle vicinity.

The excitation electrode 15 including the first excitation electrode 13 and the second excitation electrode 14 is an electrode that vibrates the pair of vibrating arm portions 10 and 11 at a predetermined frequency in a direction approaching or separating from each other. Patterned on the outer surfaces of the arms 10 and 11 while being electrically separated from each other.
Specifically, the first excitation electrode 13 is mainly formed on the groove portion 18 of one vibrating arm portion 10 and on both side surfaces of the other vibrating arm portion 11. Further, the second excitation electrode 14 is mainly formed on both side surfaces of the one vibrating arm portion 10 and on the groove portion 18 of the other vibrating arm portion 11.

Further, the first excitation electrode 13 and the second excitation electrode 14 are electrically connected to the mount electrodes 16 and 17 via the extraction electrodes 19 and 20, respectively, on both main surfaces of the base portion 12. The piezoelectric vibrating reed 4 is applied with a voltage via the mount electrodes 16 and 17.
The excitation electrode 15, the mount electrodes 16 and 17, and the extraction electrodes 19 and 20 described above are, for example, conductive films such as chromium (Cr), nickel (Ni), aluminum (Al), and titanium (Ti). It is formed by.

Further, a weight metal film 21 for frequency adjustment is coated on the tips of the pair of vibrating arm portions 10 and 11 so as to vibrate its own vibration state within a predetermined frequency range.
Here, the weight metal film 21 is made of, for example, silver (Ag) or gold (Au). The weight metal film 21 is a coarse / fine-tuning film 21a used when the frequency is coarsely adjusted. It is divided into the fine-tuning film 21b used. By adjusting the frequency using the weight of the coarse / fine adjustment film 21a and the fine adjustment film 21b, the frequency of the pair of vibrating arm portions 10 and 11 can be within the range of the target frequency of the device (details will be described later). To do).

  As shown in FIGS. 3 and 4, the piezoelectric vibrating reed 4 configured in this way is bump-bonded to the upper surface of the base substrate 2 using bumps B such as gold. More specifically, bump bonding is performed with a pair of mount electrodes 16 and 17 in contact with two bumps B formed on lead electrodes 36 and 37 (described later) patterned on the upper surface of the base substrate 2. ing. As a result, the piezoelectric vibrating reed 4 is supported in a state where it floats from the upper surface of the base substrate 2, and the mount electrodes 16 and 17 and the routing electrodes 36 and 37 are electrically connected to each other.

  As shown in FIGS. 1, 3, and 4, the lid substrate 3 is a transparent insulating substrate made of a glass material, for example, soda-lime glass, and is formed in a plate shape. A rectangular recess 3a in which the piezoelectric vibrating reed 4 is accommodated is formed on the bonding surface side to which the base substrate 2 is bonded. The recess 3 a is a cavity recess that becomes a cavity C that accommodates the piezoelectric vibrating reed 4 when the substrates 2 and 3 are overlapped. The lid substrate 3 is anodically bonded to the base substrate 2 with the recess 3a facing the base substrate 2 side.

  As shown in FIGS. 1 to 4, the base substrate 2 is a transparent insulating substrate made of a glass material, for example, soda-lime glass, like the lid substrate 3, and has a size that can be superimposed on the lid substrate 3. It is formed in a plate shape. The base substrate 2 is formed with a pair of through holes 30 and 31 penetrating the base substrate 2. At this time, the pair of through holes 30 and 31 are formed so as to be accommodated in the cavity C.

More specifically, one of the through holes 30 and 31 of the present embodiment is formed at a position corresponding to the base 12 side of the mounted piezoelectric vibrating reed 4. The other through hole 31 is formed at a position corresponding to the distal end side of the vibrating arm portions 10 and 11. In addition, the through holes 30 and 31 are formed in a tapered shape with a gradually decreasing diameter from the lower surface to the upper surface of the base substrate 2.
In the present embodiment, the case where each of the through holes 30 and 31 is formed in a tapered shape has been described. However, the present invention is not limited to this, and may be a through hole that passes straight through the base substrate 2. In any case, it only needs to penetrate the base substrate 2.

The pair of through holes 30 and 31 are formed with a pair of through electrodes 32 and 33 formed so as to fill the through holes 30 and 31.
As shown in FIG. 3, the through electrodes 32 and 33 are formed by the cylindrical body 6 and the core member 7 that are integrally fixed to the through holes 30 and 31 by firing. The through electrodes 32 and 33 completely close the through holes 30 and 31 to maintain the airtightness in the cavity C, and also have a role of conducting the external electrodes 38 and 39 described later and the lead electrodes 36 and 37. ing.

  The cylinder 6 is obtained by baking paste-like glass frit. The cylindrical body 6 is formed in a cylindrical shape having flat ends and substantially the same thickness as the base substrate 2. And the core part 7 is distribute | arranged to the center of the cylinder 6 so that the cylinder 6 may be penetrated. In the present embodiment, the outer shape of the cylindrical body 6 is formed in a conical shape (tapered cross section) according to the shape of the through holes 30 and 31. The cylindrical body 6 is fired in a state of being embedded in the through holes 30 and 31, and is firmly fixed to the through holes 30 and 31.

The core material portion 7 is a conductive core material formed in a cylindrical shape from a metal material, and is formed so that both ends are flat and substantially the same thickness as the thickness of the base substrate 2, similar to the cylindrical body 6. ing.
As shown in FIG. 3, when the through electrodes 32 and 33 are formed as finished products, the core member 7 is formed so as to have substantially the same thickness as the base substrate 2. However, in the manufacturing process, the length of the core member 7 is set to be 0.02 mm shorter than the initial thickness of the base substrate 2 in the manufacturing process. The core member 7 is located in the center hole 6 c of the cylinder 6 and is firmly fixed to the cylinder 6 by firing the cylinder 6.
In addition, the through electrodes 32 and 33 are ensured to have electrical conductivity through the conductive core portion 7.

  As shown in FIGS. 1 to 4, a bonding material 35 made of Al for anodic bonding is formed on the upper surface side of the base substrate 2 (the bonding surface side to which the lid substrate 3 is bonded) with a conductive material (for example, aluminum). The pair of lead-out electrodes 36 and 37 are patterned. Among these, the bonding material 35 is formed along the periphery of the base substrate 2 so as to surround the periphery of the recess 3 a formed in the lid substrate 3.

The pair of lead-out electrodes 36 and 37 electrically connect one of the through electrodes 32 and 33 to the one mount electrode 16 of the piezoelectric vibrating piece 4 and the other through electrode. 33 and the other mount electrode 17 of the piezoelectric vibrating reed 4 are patterned so as to be electrically connected.
More specifically, the one lead-out electrode 36 is formed directly above the one through electrode 32 so as to be positioned directly below the base 12 of the piezoelectric vibrating piece 4. The other routing electrode 37 is routed from the position adjacent to the one routing electrode 36 along the vibrating arm portions 10 and 11 to the distal end side of the vibrating arm portions 10 and 11, and then the other through electrode 33. It is formed so that it may be located just above.

  Bumps B are formed on the pair of lead-out electrodes 36 and 37, and the piezoelectric vibrating reed 4 is mounted using the bumps B. As a result, the one mount electrode 16 of the piezoelectric vibrating reed 4 is electrically connected to the one through electrode 32 via the one lead-out electrode 36. The other mount electrode 17 is electrically connected to the other through electrode 33 via the other lead-out electrode 37.

As shown in FIGS. 1, 3, and 4, external electrodes 38 and 39 that are electrically connected to the pair of through electrodes 32 and 33 are formed on the lower surface of the base substrate 2. That is, one external electrode 38 is electrically connected to the first excitation electrode 13 of the piezoelectric vibrating reed 4 through one through electrode 32 and one routing electrode 36.
The other external electrode 39 is electrically connected to the second excitation electrode 14 of the piezoelectric vibrating reed 4 via the other through electrode 33 and the other routing electrode 37.

  When the piezoelectric vibrator 1 configured in this way is operated, a predetermined drive voltage is applied to the external electrodes 38 and 39 formed on the base substrate 2. As a result, a current can be passed through the excitation electrode 15 including the first excitation electrode 13 and the second excitation electrode 14 of the piezoelectric vibrating reed 4 in a direction in which the pair of vibrating arm portions 10 and 11 are approached and separated. It can be vibrated at a predetermined frequency. The vibration of the pair of vibrating arm portions 10 and 11 can be used as a time source, a control signal timing source, a reference signal source, and the like.

(Piezoelectric vibrator manufacturing method)
Next, a method for manufacturing the piezoelectric vibrator 1 will be described with reference to FIGS. FIG. 8 is a flowchart showing a method for manufacturing a piezoelectric vibrator, FIG. 9 is a flowchart showing a piezoelectric vibrating piece manufacturing process, and FIG. 10 is an exploded perspective view of the wafer bonded body 60. 11 to 13 are process diagrams showing a method of manufacturing a piezoelectric vibrator. In FIGS. 11 to 13, the scale of each part is appropriately changed to make each part recognizable.

  Here, as shown in FIGS. 8 and 10, in the method of manufacturing the piezoelectric vibrator 1, a base substrate wafer 40 in which a plurality of base substrates 2 are connected and a lid substrate wafer 50 in which a plurality of lid substrates 3 are connected. A method of simultaneously manufacturing a plurality of piezoelectric vibrators 1 by enclosing a plurality of piezoelectric vibrating pieces 4 to form a wafer bonded body 60 and cutting the wafer bonded body 60 will be described. A broken line M shown in FIG. 13 illustrates a cutting line that is cut in the cutting process.

  The manufacturing method of the piezoelectric vibrator 1 in this embodiment mainly includes a piezoelectric vibrating piece manufacturing step (S10), a lid substrate wafer manufacturing step (S20), a base substrate wafer manufacturing step (S30), and an assembly step. (S40 and below). Among these, the piezoelectric vibrating reed manufacturing step (S10), the lid substrate wafer manufacturing step (S20), and the base substrate wafer manufacturing step (S30) can be performed in parallel.

(Piezoelectric vibrating piece manufacturing process)
First, as shown in FIGS. 8 and 9, the piezoelectric vibrating reed manufacturing step (S10) is performed to manufacture the piezoelectric vibrating reed 4 (see FIGS. 5 and 6). More specifically, a quartz Lambert rough is sliced at a predetermined angle to obtain a wafer (not shown) having a constant thickness. Subsequently, the wafer is lapped and roughly processed, and then the work-affected layer is removed by etching, and then mirror processing such as polishing is performed to obtain a predetermined thickness (S110).

  Next, an outer pattern (not shown) for patterning the outer shapes of the plurality of piezoelectric plates 24 is formed from the wafer (outer pattern forming step, S120). The outer shape pattern is formed by patterning a metal film in accordance with the outer shape of the pair of vibrating arm portions 10 and 11 and the base portion 5 on both surfaces of the polished wafer. At this time, patterning is performed collectively for the plurality of piezoelectric vibrating reeds 4 formed on the wafer.

Next, using the patterned outer pattern as a mask, etching is performed from both sides of the wafer (S130). As a result, the region not masked with the outer shape pattern is selectively removed. As a result, the wafer patterned by the outer shape pattern is formed in the outer shape of the piezoelectric plate 24.
Subsequently, a groove portion forming step is performed in which the groove portion 18 is formed on both main surfaces of the pair of vibrating arm portions 10 and 11 (see FIGS. 5 and 6) (S140). The groove portion 18 can be formed by etching the vibrating arm portions 10 and 11.

  Next, the electrode film is patterned on the outer surfaces of the plurality of piezoelectric plates 24 to perform an electrode formation step of forming the excitation electrodes 13 and 14, the extraction electrodes 19 and 20, and the mount electrodes 16 and 17, respectively (S150). Specifically, an electrode film is formed on the outer surface of the piezoelectric plate 24 in which the groove 18 is formed by a vapor deposition method, a sputtering method, or the like, and thereafter, the electrode film is formed by etching.

  After the electrode formation step (S150) is completed, the weight metal film 21 including the frequency adjustment coarse / fine adjustment film 21a and the fine adjustment film 21b is formed at the tips of the pair of vibrating arms 10 and 11 (weight metal film formation step). , S160). The weight metal film 21 has a laminated structure in which a fine adjustment film 21b is first formed and then a coarse adjustment film 21a is formed thereon. The fine adjustment film 21b has a film thickness of about 1500 mm, for example, while the coarse / fine adjustment film 21a has a film thickness of about 3 μm, for example.

Subsequently, as shown in FIGS. 9 and 11, a coarse adjustment process for coarsely adjusting the frequency is performed on all the vibrating arm portions 10 and 11 formed on the wafer using a trimming device (not shown) (S170). ).
Here, the trimming device includes a frequency measuring device that measures the frequency of the vibrating arm portions 10 and 11, a trimming amount calculator that calculates a trimming amount based on the measurement result of the frequency measuring device, and a calculation result of the trimming amount calculator. And a laser control device for irradiating the weight metal film 21 of the vibrating arm portions 10 and 11 with laser light (both not shown).

More specifically, the rough adjustment step (S170) will be described. First, the frequencies of all the vibrating arm portions 10 and 11 are collectively measured using a frequency measuring device (frequency measuring step, S171).
Thereafter, the trimming amount is calculated by the trimming amount calculator according to the difference between the measured frequency and the predetermined target frequency (trimming amount calculating step, S172). In this coarse adjustment step, the amount of deviation between the measured frequency and a predetermined target frequency is set to, for example, 800 ppm to 450 ppm. In this case, the trimming amount is calculated as a trimming amount capable of keeping the shift amount within 800 ppm to 450 ppm.

Thereafter, based on the calculation result of the trimming amount, the laser control device irradiates the tip of the coarse / fine adjustment film 21a of the weight metal film 21 with laser light to remove (trim) the coarse / fine adjustment film 21a, thereby removing the line-shaped removal. A portion 71 is formed (trimming step, S173).
Here, when it is not possible to fit within a predetermined shift amount (for example, 800 ppm to 450 ppm) simply by forming the removal portion 71 for one line at the tip of the coarse / fine adjustment film 21a, the vibrating arm portion is again used by using the frequency measuring device. 10 and 11 frequencies are measured.

  Thereafter, the trimming amount is recalculated by the trimming amount calculator again according to the difference between the measured frequency and a predetermined target frequency, and the coarse / fine-tuning film 21a of the weight metal film 21 is irradiated with laser light to be rough. The fine adjustment film 21a is removed in a line shape. Then, by repeating this, the deviation amount between the measured frequency and a predetermined target frequency is set to, for example, 800 ppm to 450 ppm.

Note that, as shown in FIG. 11, in this embodiment, two lines of removal portions 71 are formed. That is, the rough fine adjustment film 21a removal operation (trimming operation) in the rough adjustment step (S170) is performed twice. In this way, the coarse adjustment step (S170) ends.
Here, the fine adjustment step of adjusting the frequencies of the vibrating arm portions 10 and 11 with higher accuracy is performed after the piezoelectric vibrating reed 4 is sealed in the package 5.

As shown in FIG. 9, after the coarse adjustment step (S170) is completed, the connecting portion that finally connected the wafer and the piezoelectric plate 24 is cut, and the plurality of piezoelectric plates 24 are separated from the wafer to be separated into individual pieces. A cutting step is performed (S180). As a result, a plurality of tuning-fork type piezoelectric vibrating reeds 4 can be manufactured from a single wafer at a time.
At this point, the manufacturing process of the piezoelectric vibrating piece 4 is finished, and the piezoelectric vibrating piece 4 shown in FIG. 5 can be obtained.

(Wad production process for lid substrate)
Next, as shown in FIGS. 8 and 10, a lid substrate wafer manufacturing process is performed in which a lid substrate wafer 50 to be the lid substrate 3 later is manufactured up to a state just before anodic bonding (S20).
Specifically, after polishing and cleaning soda-lime glass to a predetermined thickness, a disk-shaped lid substrate wafer 50 is formed by removing the outermost work-affected layer by etching or the like (S21).

Next, a recess forming step is performed in which a plurality of recesses 3a for the cavity C are formed in the matrix direction by etching or the like on the back surface 50a (the lower surface in FIG. 6) of the lid substrate wafer 50 (S22).
Subsequently, in order to ensure airtightness with the base substrate wafer 40, which will be described later, a polishing step (S23) for polishing at least the back surface 50a side of the lid substrate wafer 50 to be a bonding surface with the base substrate wafer 40 (S23). ) To mirror-finish the back surface 50a. The lid substrate wafer creation step (S20) is thus completed.

(Base substrate wafer creation process)
Next, a base substrate wafer manufacturing step is performed in which the base substrate wafer 40 to be the base substrate 2 later is manufactured up to the state immediately before anodic bonding at the same time as before or after the above-described step (S30).
First, after polishing and washing soda-lime glass to a predetermined thickness, a disk-shaped base substrate wafer 40 is formed by removing the outermost work-affected layer by etching or the like (S31).

Next, a through hole forming step is performed in which a plurality of through holes 30 and 32 for arranging the pair of through electrodes 32 and 33 are formed in the base substrate wafer by, for example, pressing (S32).
Specifically, after forming a concave portion from the back surface 40b of the base substrate wafer 40 by pressing or the like, the concave portion is penetrated by polishing at least from the front surface 40a side of the base substrate wafer 40, and the through holes 30, 31 are formed. Can be formed.

Subsequently, a through electrode forming step (S33) for forming the through electrodes 32 and 33 in the through holes 30 and 31 formed in the through hole forming step (S32) is performed.
As a result, in the through holes 30 and 31, the core portion 7 is held in a state of being flush with both surfaces 40a and 40b (upper and lower surfaces in FIG. 6) of the base substrate wafer 40. Thus, the through electrodes 32 and 33 can be formed.

Next, a conductive material is patterned on the surface 40a of the base substrate wafer 40 to perform a bonding material forming step for forming the bonding material 35 (S34), and a routing electrode forming step is performed (S35).
The bonding material 35 is formed over the entire region of the base substrate wafer 40 other than the region where the cavity C is formed, that is, the entire bonding region with the back surface 50a of the lid substrate wafer 50. In this way, the base substrate wafer manufacturing step (S30) is completed.

Subsequently, the piezoelectric vibrating reed 4 created in the piezoelectric vibrating reed creating step (S10) is respectively formed on the routing electrodes 36 and 37 of the base substrate wafer 40 created in the base substrate wafer creating step (S30). Mounting is performed via a bump B such as gold (mounting step, S40).
Then, a superimposition process is performed in which the base substrate wafer 40 and the lid substrate wafer 50 created in the above-described production processes of the wafers 40 and 50 are superposed (superposition process, S50).
Specifically, both wafers 40 and 50 are aligned at the correct positions while using a reference mark (not shown) as an index. As a result, the mounted piezoelectric vibrating reed 4 is housed in the cavity C surrounded by the recess 3 a formed in the lid substrate wafer 50 and the base substrate wafer 40.

After the superposition process, the two superposed wafers 40 and 50 are put into an anodic bonding apparatus (not shown), and a predetermined voltage is applied in a predetermined temperature atmosphere with the outer peripheral portion of the wafer clamped by a holding mechanism (not shown). Then, a bonding step for anodic bonding is performed (S60).
Specifically, a predetermined voltage is applied between the bonding material 35 and the lid substrate wafer 50. As a result, an electrochemical reaction occurs at the interface between the bonding material 35 and the lid substrate wafer 50, and the two are firmly adhered to each other and anodic bonded. Thereby, the piezoelectric vibrating reed 4 can be sealed in the cavity C, and the wafer bonded body 60 in which the base substrate wafer 40 and the lid substrate wafer 50 are bonded can be obtained.

Then, the two wafers 40 and 50 are anodically bonded as in the present embodiment, so that compared with the case where the two wafers 40 and 50 are bonded with an adhesive or the like, a shift due to deterioration with time, impact, etc. Thus, both wafers 40 and 50 can be bonded more firmly.
In this case, in the present embodiment, since Al having a relatively low resistance value is used for the bonding material 35, a voltage can be uniformly applied to the entire surface of the bonding material 35, and the bonding surfaces of both wafers 40, 50 It is possible to easily form the wafer bonded body 60 in which the two are firmly anodically bonded. In addition, since anodic bonding can be performed at a relatively low voltage, energy consumption can be reduced and manufacturing costs can be reduced.

Subsequently, as shown in FIGS. 8 and 11, a trimming device (not shown) performs a fine adjustment step of finely adjusting the frequency of each piezoelectric vibrating piece 4 sealed in the package 5 to be within the target frequency range. (S80).
Note that the trimming apparatus used in the fine adjustment process is also the same as or similar in configuration to the trimming apparatus used in the coarse adjustment process (S170 in FIG. 9), and thus the description of the trimming apparatus is omitted.

The fine adjustment step will be described in detail. First, a voltage is applied to the external electrodes 38 and 39, and the frequencies of all the vibrating arm portions 10 and 11 are collectively measured using a frequency measuring device (frequency measurement step, S81).
Thereafter, the trimming amount is calculated by the trimming amount calculator in accordance with the difference between the measured frequency and a predetermined target frequency (trimming amount calculating step, S82).

Here, a plurality of trimming patterns 72 corresponding to the trimming amount calculated by the trimming amount calculator are preset in the trimming apparatus. Then, a desired trimming pattern 72 is selected according to the calculated trimming amount, and the coarse / fine adjustment film 21a and the fine adjustment film 21b are removed using the trimming pattern 72 (pattern processing step, S83).
Specifically, using the selected trimming pattern 72, the laser control device irradiates the coarse / fine-adjusted film 21a and the fine-adjusted film 21b with laser light to form spots 73, that is, removal portions 74.

  In the pattern processing step (S83), the removal unit 74 is formed so that the amount of deviation between the frequency measured in the frequency measurement step (S81) and a predetermined target frequency falls within, for example, about 50 ppm. For this reason, the trimming pattern 72 selected according to the trimming amount formed in the trimming amount calculation step (S82) is different.

For example, as shown in FIG. 11, one of the plurality of trimming patterns 72 has five spots 73 formed on the coarse / fine adjustment film 21a and two spots 73 formed on the fine adjustment film 21b. Yes.
In other words, the trimming pattern 72 shown in FIG. 11 is formed so as to form a plurality of spots 73 which are formed across the coarse / fine adjustment film 21a and the fine adjustment film 21b of the weight metal film 21 and are spaced apart from each other. Has been. The coarse / fine adjustment film 21a and the fine adjustment film 21b are removed in one pattern processing step (S83).

In addition to the trimming pattern 72 as shown in FIG. 11, there are patterns as shown in FIGS. For example, when the amount of deviation in the pattern processing step (S83) is about 50 ppm, the amount of deviation between the frequency measured in the frequency measurement step (S81) and a predetermined target frequency is 800 ppm. In this case, in the trimming amount calculation step (S82), a trimming amount of about 750 ppm is calculated in order to keep the deviation amount to about 50 ppm.
In this case, as shown in FIG. 12, a trimming pattern 72 ′ that forms nine spots 73 on the coarse / fine adjustment film 21a is selected.

On the other hand, for example, when the shift amount of the pattern processing step (S83) is about 50 ppm, the shift amount between the frequency measured in the frequency measurement step (S81) and the predetermined target frequency is 450 ppm. In this case, in the trimming amount calculation step (S82), a trimming amount of about 400 ppm is calculated in order to keep the deviation amount to about 50 ppm.
In this case, as shown in FIG. 13, a trimming pattern 72 ″ that forms five spots 73 on the coarse / fine adjustment film 21a and three spots 73 on the fine adjustment film 21b is selected.

As shown in FIGS. 8 and 11, after the pattern processing step (S83) is completed, a final adjustment step is performed so that the frequency of the piezoelectric vibrating reed 4 falls within the target frequency (S84).
Specifically, the frequencies of all the vibrating arm portions 10 and 11 are again measured together using a frequency measuring device. Thereafter, the trimming amount is calculated again according to the difference between the measured frequency and a predetermined target frequency by the trimming amount calculator, and the fine adjustment film 21b is irradiated with laser light to remove the fine adjustment film 21b in a spot shape. Part 75 is formed (see part C in FIG. 11).
In the final adjustment step (S84), if the target frequency cannot be achieved by one tring operation, the final adjustment step (S84) can be repeated several times. And the frequency of all the vibrating arm parts 10 and 11 is made into the target frequency, and a fine adjustment process (S80) is complete | finished.

After the fine adjustment step (S80) is completed, an individualization step for cutting the bonded wafer bonded body 60 into individual pieces is performed (S90).
In the singulation step (S90), the wafer bonded body 60 is held by a magazine (not shown), the surface layer portion of the surface 50b of the lid substrate wafer 50 is irradiated with laser light along the cutting line M, and the wafer A scribe line is formed in the joined body 60.

  Then, braking is performed on the wafer bonded body 60 on which the scribe line is formed, and cleaving stress is applied to the wafer bonded body 60. Then, a crack is generated in the wafer bonded body 60 along the thickness direction, and the wafer bonded body 60 is cut so as to be folded along a scribe line formed on the lid substrate wafer 50. Then, by pressing a cutting blade (not shown) for each scribe line, the wafer bonded body 60 is collectively separated into the package 5 (piezoelectric vibrator 1) for each cutting line M.

Subsequently, an electrical characteristic inspection inside the separated piezoelectric vibrator 1 is performed (S100).
In the electrical characteristic inspection (S100), the frequency, resistance value, drive level characteristic (frequency and resistance value dependency of excitation power) of the piezoelectric vibrating piece 4 are measured and checked. In addition, the insulation resistance characteristics and the like are also checked. Then, an external appearance inspection of the piezoelectric vibrator 1 is performed to finally check dimensions and quality. This completes the manufacture of the piezoelectric vibrator 1.

  Therefore, according to the above-described embodiment, in the fine adjustment step (S80), it is possible to selectively use the plurality of trimming processing patterns 72 and perform the pattern processing step (S83 in FIG. 8) only once. A predetermined amount of the 21a and the fine-tuning film 21b can be removed. For this reason, it is not necessary to repeat the measurement of the frequencies of the vibrating arm portions 10 and 11 and the removal work of the respective films 21a and 21b as in the prior art, and the number of steps in the fine adjustment step (S80) can be reduced. Therefore, it is possible to shorten the time until the piezoelectric vibrator 1 falls within the target frequency range.

Further, as shown in FIGS. 11 to 13, the trimming pattern 72 is set so as to form a plurality of spots 73 that are spaced apart from each other, so that the rough fine-tuning film 21 a and the fine-tuning film 21 b are formed. The amount of the films 21a and 21b to be removed can be adjusted with high accuracy as compared with the case of removing them in a line shape as in the prior art.
That is, when removing the coarse / fine adjustment film 21a and the fine adjustment film 21b in a line shape, the processing error becomes larger than when the spot 73 is formed. This is because the diameter of the spot 73 is determined by the spot diameter of the laser beam, which is easy to control. On the other hand, when removing the coarse / fine adjustment film 21a or the fine adjustment film 21b in a line shape, the laser beam or the piezoelectric vibrating piece 4 is scanned. This is because the distance needs to be controlled, and the error increases accordingly.
For this reason, the frequency adjustment in the pattern processing step (S83) can be performed with high accuracy, and the number of work steps in the final adjustment step (S84) can be reduced. As a result, the time until the piezoelectric vibrator 1 falls within the target frequency range can be shortened more reliably.

(Modification of the embodiment)
In the method of manufacturing the piezoelectric vibrator 1 according to the above-described embodiment, the case where the coarse adjustment step of coarsely adjusting the frequency of the piezoelectric vibrating reed 4 is first performed in the piezoelectric vibrating reed manufacturing step (S10) (S170) has been described. However, the present invention is not limited to this, and the coarse adjustment step (S170) may be included in the pattern processing step (S83) of the fine adjustment step (S80).

More specifically, a description will be given based on FIG. FIG. 14 is a process diagram showing a method for manufacturing a piezoelectric vibrator in a modification of the present embodiment. In FIG. 14, the same aspects as those of the above-described embodiment are denoted by the same reference numerals and description thereof is omitted.
As shown in the figure, a plurality of trimming patterns 76 set in advance in a trimming apparatus (not shown) also form a spot 73 at the tip of the coarse / fine adjustment film 21a removed in the coarse adjustment step (S170). Is set to That is, the three spots 73 formed at the tips of the coarse / fine adjustment films 21a of the vibrating arm portions 10 and 11 in FIG. 14 are configured as coarse adjustment patterns 77 for coarse adjustment.

  In such a case, the rough adjustment step (S170) of the piezoelectric vibrating piece manufacturing step (S10) is deleted, and after the frequency measurement step (S81) and the trimming amount calculation step (S82) in the fine adjustment step (S80), trimming processing is performed. Based on the pattern 76, the coarse and fine adjustment film 21a and the fine adjustment film 21b are irradiated with laser light, and a plurality of spots 73 (removal portions 74) are formed on the respective films 21a and 21b at a stretch.

  Therefore, according to the above-described modification, the trimming pattern 76 includes the coarse adjustment pattern 77 for coarse adjustment, and in the fine adjustment step (S80), it is possible to perform the rough adjustment step and the fine adjustment step all at once. Become. For this reason, the rough adjustment step (S170) in the piezoelectric vibrating piece manufacturing step (S10) can be eliminated, and the manufacturing time of the piezoelectric vibrator 1 can be further shortened.

(Oscillator)
Next, an embodiment of an oscillator according to the present invention will be described with reference to FIG.
FIG. 15 is a schematic configuration diagram of the oscillator 100.
As shown in the figure, the oscillator 100 is configured as an oscillator in which the piezoelectric vibrator 1 is electrically connected to the integrated circuit 101. The oscillator 100 includes a substrate 103 on which an electronic component 102 such as a capacitor is mounted. An integrated circuit 101 for an oscillator is mounted on the substrate 103, and the piezoelectric vibrator 1 is mounted in the vicinity of the integrated circuit 101.
The electronic component 102, the integrated circuit 101, and the piezoelectric vibrator 1 are electrically connected by a wiring pattern (not shown). Each component is molded with a resin (not shown).

In the oscillator 100 configured as described above, when a voltage is applied to the piezoelectric vibrator 1, the piezoelectric vibrating reed 4 in the piezoelectric vibrator 1 vibrates. This vibration is converted into an electric signal by the piezoelectric characteristics of the piezoelectric vibrating piece 4 and input to the integrated circuit 101 as an electric signal. The input electrical signal is subjected to various processes by the integrated circuit 101 and is output as a frequency signal. Thereby, the piezoelectric vibrator 1 functions as an oscillator.
Further, by selectively setting the configuration of the integrated circuit 101, for example, an RTC (real-time clock) module or the like according to a request, the operation date and time of the device and the external device in addition to a single-function oscillator for a clock, etc. A function for controlling the time, providing a time, a calendar, and the like can be added.

  Therefore, according to the oscillator 100 of the present embodiment, since the piezoelectric vibrator 1 in which the airtightness in the cavity C is ensured is provided, the high-quality oscillator 100 having excellent characteristics and reliability can be provided. In addition to this, a stable and highly accurate frequency signal can be obtained over a long period of time.

(Electronics)
Next, one embodiment of the electronic apparatus of the present invention will be described with reference to FIG. Note that the portable information device 110 having the above-described piezoelectric vibrator 1 will be described as an example of the electronic device.
FIG. 16 is a schematic configuration diagram of the portable information device 110.
Here, the portable information device 110 is typified by a mobile phone, for example, and is a development and improvement of a wrist watch in the prior art. The appearance is similar to that of a wristwatch, and a liquid crystal display is arranged in a portion corresponding to a dial so that the current time and the like can be displayed on this screen. Further, when used as a communication device, it is possible to perform communication similar to that of a conventional mobile phone by using a speaker and a microphone which are removed from the wrist and incorporated in the inner portion of the band. However, it is much smaller and lighter than conventional mobile phones.

  As shown in FIG. 16, the portable information device 110 includes the piezoelectric vibrator 1 and a power supply unit 111 for supplying power. The power supply unit 111 is made of, for example, a lithium secondary battery. The power supply unit 111 includes a control unit 112 that performs various controls, a clock unit 113 that counts time, a communication unit 114 that communicates with the outside, a display unit 115 that displays various types of information, A voltage detection unit 116 that detects the voltage of the functional unit is connected in parallel. The power unit 111 supplies power to each functional unit.

  The control unit 112 controls each function unit to perform operation control of the entire system such as transmission and reception of audio data, measurement and display of the current time, and the like. The control unit 112 includes a ROM in which a program is written in advance, a CPU that reads and executes the program written in the ROM, and a RAM that is used as a work area of the CPU.

The timer unit 113 includes an integrated circuit including an oscillation circuit, a register circuit, a counter circuit, an interface circuit, and the like, and the piezoelectric vibrator 1. When a voltage is applied to the piezoelectric vibrator 1, the piezoelectric vibrating piece 4 vibrates, and the vibration is converted into an electric signal by the piezoelectric characteristics of the crystal, and is input to the oscillation circuit as an electric signal.
The output of the oscillation circuit is binarized and counted by a register circuit and a counter circuit. Then, signals are transmitted to and received from the control unit 112 via the interface circuit, and the current time, current date, calendar information, or the like is displayed on the display unit 115.

The communication unit 114 has functions similar to those of a conventional mobile phone, and includes a radio unit 117, a voice processing unit 118, a switching unit 119, an amplification unit 120, a voice input / output unit 121, a telephone number input unit 122, and a ring tone generation unit. 123, and a call control memory unit 124.
The wireless unit 117 exchanges various data such as audio data with the base station via the antenna 125. The audio processing unit 118 encodes and decodes the audio signal input from the radio unit 117 or the amplification unit 120. The amplifying unit 120 amplifies the signal input from the audio processing unit 118 or the audio input / output unit 121 to a predetermined level. The voice input / output unit 121 includes a speaker, a microphone, and the like, and amplifies a ringtone and a received voice or collects a voice.

In addition, the ring tone generator 123 generates a ring tone in response to a call from the base station. The switching unit 119 switches the amplifying unit 120 connected to the voice processing unit 118 to the ringing tone generating unit 123 only when an incoming call is received. To the audio input / output unit 121.
The call control memory unit 124 stores a program related to incoming / outgoing call control of communication. The telephone number input unit 122 includes, for example, number keys from 0 to 9 and other keys, and a telephone number of a call destination is input by pressing these number keys.

When the voltage applied to each functional unit such as the control unit 112 by the power supply unit 111 falls below a predetermined value, the voltage detection unit 116 detects the voltage drop and notifies the control unit 112 of the voltage drop. . The predetermined voltage value at this time is a value set in advance as a minimum voltage necessary for stably operating the communication unit 114, and is, for example, about 3V.
Upon receiving the voltage drop notification from the voltage detection unit 116, the control unit 112 prohibits the operations of the radio unit 117, the voice processing unit 118, the switching unit 119, and the ring tone generation unit 123. In particular, it is essential to stop the operation of the wireless unit 117 with high power consumption. Further, the display unit 115 displays that the communication unit 114 has become unusable due to insufficient battery power.

That is, the operation of the communication unit 114 can be prohibited by the voltage detection unit 116 and the control unit 112, and that effect can be displayed on the display unit 115. This display may be a text message, but as a more intuitive display, a x (X) mark may be attached to the telephone icon displayed at the top of the display surface of the display unit 115.
In addition, the function of the communication part 114 can be stopped more reliably by providing the power supply cutoff part 126 that can selectively cut off the power of the part related to the function of the communication part 114.

  Therefore, according to the portable information device 110 of this embodiment, since the piezoelectric vibrator 1 in which the airtightness in the cavity C is ensured is provided, the high-quality portable information device 110 having excellent characteristics and reliability can be provided. . In addition to this, it is possible to display highly accurate clock information that is stable over a long period of time.

(Radio watch)
Next, an embodiment of the radio timepiece of the present invention will be described with reference to FIG.
FIG. 17 is a schematic configuration diagram of the radio timepiece 130.
Here, the radio timepiece 130 includes the piezoelectric vibrator 1 electrically connected to the filter unit 131, receives a standard radio wave including timepiece information, and automatically corrects and displays it at an accurate time. It is a watch with the function to do.
In Japan, there are transmitting stations (transmitting stations) that transmit standard radio waves in Fukushima Prefecture (40 kHz) and Saga Prefecture (60 kHz), each transmitting standard radio waves. Long waves such as 40 kHz or 60 kHz have the property of propagating the surface of the earth and the property of propagating while reflecting the ionosphere and the surface of the earth, so the propagation range is wide and the above two transmitting stations cover all of Japan is doing.

As shown in FIG. 17, the antenna 132 of the radio timepiece 130 receives a long standard wave of 40 kHz or 60 kHz. The long-wave standard radio wave is obtained by subjecting time information called a time code to AM modulation on a 40 kHz or 60 kHz carrier wave. The received long standard wave is amplified by the amplifier 133 and filtered and tuned by the filter unit 131 having the plurality of piezoelectric vibrators 1.
The piezoelectric vibrator 1 according to this embodiment includes crystal vibrator portions 138 and 139 having resonance frequencies of 40 kHz and 60 kHz, which are the same as the carrier frequency.

Further, the filtered signal having a predetermined frequency is detected and demodulated by the detection and rectification circuit 134.
Subsequently, the time code is taken out via the waveform shaping circuit 135 and counted by the CPU 136. The CPU 136 reads information such as the current year, accumulated date, day of the week, and time. The read information is reflected in the RTC 137, and accurate time information is displayed.
Since the carrier wave is 40 kHz or 60 kHz, the crystal vibrator units 138 and 139 are preferably vibrators having the tuning fork type structure described above.

  In addition, although the above-mentioned description was shown in the example in Japan, the frequency of the long standard wave is different overseas. For example, in Germany, a standard radio wave of 77.5 KHz is used. Accordingly, when the radio timepiece 130 that can be used overseas is incorporated in a portable device, the piezoelectric vibrator 1 having a frequency different from that in Japan is required.

  Therefore, according to the radio timepiece 130 of this embodiment, since the piezoelectric vibrator 1 in which the airtightness in the cavity C is ensured is provided, a high quality radio timepiece 130 having excellent characteristics and reliability can be provided. In addition to this, it is possible to count the time with high accuracy and stability over a long period of time.

The present invention is not limited to the above-described embodiment, and includes various modifications made to the above-described embodiment without departing from the spirit of the present invention.
For example, in the fine tuning step (S80, see FIG. 8) in the method of manufacturing the piezoelectric vibrator 1, a plurality of trimming patterns 72 and 76 are set in advance in a trimming apparatus (not shown). In the above description, a case is described in which a plurality of spots 73 (removal portions 74) are formed on the coarse / fine adjustment film 21a and the fine adjustment film 21b. However, the present invention is not limited to this, and the trimming patterns 72 and 76 may be configured to form at least one spot 73.
Moreover, you may comprise the trimming process patterns 72 and 76 by the spot 73 and the removal part 71 (refer FIG. 11) formed in a line form.

  Furthermore, in the above-described embodiment, in the bonding step (S60), a bonding auxiliary material serving as an anode is disposed on the back surface 40b of the base substrate wafer 40, and a cathode is disposed on the front surface 50b of the lid substrate wafer 50 (see FIG. A so-called counter electrode method) may be employed, or the bonding material 23 is connected to the anode, a cathode is disposed on the surface 50b of the lid substrate wafer 50, and a voltage is directly applied to the bonding material 23. (So-called direct electrode method) may be adopted.

By adopting the counter electrode method, an anodic bonding reaction occurs between the bonding auxiliary material and the back surface 40b of the base substrate wafer 40 by applying a voltage between the bonding auxiliary material and the cathode during anodic bonding. In conjunction with this, the bonding material 23 and the back surface 50a of the lid substrate wafer 50 are anodically bonded. Thereby, it becomes possible to apply a voltage more uniformly to the entire surface of the bonding material 23, and the anodic bonding can be reliably performed between the bonding material 23 and the back surface 50 a of the lid substrate wafer 50.
In contrast, the direct electrode method eliminates the need to remove the bonding auxiliary material after the bonding process required by the counter electrode method, thus reducing the number of manufacturing steps and improving the manufacturing efficiency. Can be achieved.

  DESCRIPTION OF SYMBOLS 1 ... Piezoelectric vibrator 2 ... Base board | substrate 3 ... Lid board | substrate 4 ... Piezoelectric vibrating piece (tuning fork type piezoelectric vibrating piece) 5 ... Package 10, 11 ... Vibrating arm part 21 ... Weight metal film 21a ... Coarse fine adjustment film 21b ... Fine adjustment film 24 ... Piezoelectric plates 71, 74, 75 ... Removal portions 72, 76 ... Trimming pattern (processing pattern) 73 ... Spot 77 ... Coarse tone pattern 100 ... Oscillator 101 ... Oscillator integrated circuit 110 ... Portable information device (electronic device) 113 ... Timekeeping unit of electronic device 130 ... Radio clock 131 ... Filter unit of radio clock C ... Cavity S80 ... Fine adjustment process S81 ... Frequency measurement process S83 ... Pattern processing process S170 ... Coarse adjustment process

Claims (10)

A tuning fork-type piezoelectric vibrating piece in which a weight metal film made of a fine adjustment film and a fine adjustment film for frequency adjustment is formed in a vibrating arm is sealed in a package,
The coarse and fine tuning film and the fine tuning film are irradiated with laser light to partially remove the coarse and fine tuning film and the fine tuning film, thereby adjusting the frequency of the tuning fork type piezoelectric vibrating piece to a target frequency. A method of manufacturing a piezoelectric vibrator having a fine tuning process,
The fine tuning step includes
A frequency measuring step of measuring the frequency of the tuning fork type piezoelectric vibrating piece;
A pattern processing step of irradiating the laser beam with a preset processing pattern in accordance with a difference between the frequency measured by the frequency measurement step and the target frequency, and removing at least the coarse and fine adjustment film at a time. A method of manufacturing a piezoelectric vibrator.   2. The method of manufacturing a piezoelectric vibrator according to claim 1, wherein the processing pattern is set so that the coarse and fine adjustment film and the fine adjustment film are removed by the laser light at the same processing timing.   The said processing pattern is set so that the part removed by the said laser beam of the said rough fine-tuning film and the said fine-tuning film may have at least 1 spot, The Claim 1 or Claim 2 characterized by the above-mentioned. Manufacturing method of the piezoelectric vibrator.   The processing pattern is set so as to form a plurality of spots scattered in a state where the rough fine-tuning film and the portions of the fine-tuning film removed by the laser beam are spaced apart from each other. A method for manufacturing a piezoelectric vibrator according to any one of claims 1 to 3. The pattern processing step includes a rough adjustment step performed in a previous step of sealing the tuning fork type piezoelectric vibrating piece in the package,
The coarse adjustment step is a step of removing the coarse / fine adjustment film by the laser beam,
5. The method for manufacturing a piezoelectric vibrator according to claim 1, wherein a rough adjustment pattern of the coarse / fine adjustment film in the rough adjustment step is set in the processing pattern. A tuning fork type piezoelectric vibrating piece is sealed in the package,
On the vibrating arm portion of this tuning fork type piezoelectric vibrating piece, a coarse / fine adjustment film for frequency adjustment and a weight metal film made of a fine adjustment film are formed,
In the piezoelectric vibrator in which the removal portion is partially formed by irradiating the rough fine-tuning film and the fine-tuning film with laser light,
A piezoelectric vibrator, wherein a spot is formed on at least a part of the removal portion.   The piezoelectric vibrator according to claim 6, wherein the removing unit is configured by a plurality of spots formed at intervals.   8. An oscillator, wherein the piezoelectric vibrator according to claim 6 or 7 is electrically connected to an integrated circuit as an oscillator.   8. An electronic apparatus, wherein the piezoelectric vibrator according to claim 6 or 7 is electrically connected to a timer unit.   A radio-controlled timepiece, wherein the piezoelectric vibrator according to claim 6 or 7 is electrically connected to a filter portion.

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