JP2011250226A - Piezoelectric device and method for adjusting its frequency - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a frequency adjustment method for a piezoelectric wafer composed of plural piezoelectric vibration pieces of tuning-fork type with a pair of vibration arms extending from a base section which are coupled into an integral body, to adjust the frequency of the piezoelectric vibration pieces of tuning-fork type therein to a target frequency.SOLUTION: The frequency adjustment method comprises a step (S11) of forming a first metal (24) in at least part of a frequency adjustment section formed at the tip of vibration arms, a step (S12) of measuring the frequency of piezoelectric vibration pieces of tuning-fork type attached to a piezoelectric wafer (200), and steps (S13-S15) which, when the measured frequency of the piezoelectric vibration pieces of tuning-fork type is lower than a target frequency, shave off the first metal (24) formed in the frequency adjustment section and, when the measured frequency of the piezoelectric vibration pieces of tuning-fork type is higher than a target frequency, sublime a second metal (302) disposed apart from the piezoelectric vibration pieces of tuning-fork type to deposit a sublimate on the frequency adjustment section.

Description

  The present invention relates to a piezoelectric device including a tuning-fork type piezoelectric vibrating piece having a pair of vibrating arms, and a frequency adjusting method thereof.

  The manufacturing process of a piezoelectric device generally includes a process of adjusting two oscillation frequencies. The step of adjusting one oscillation frequency is a step of roughly adjusting the oscillation frequency in a state where the tuning fork type piezoelectric vibrating piece is connected to the wafer, that is, a coarse adjustment step. The other is a step of finely adjusting the oscillation frequency, that is, a fine adjustment step, with the tuning-fork type piezoelectric vibrating piece separated from the wafer being placed on the package. In these adjustment steps of the oscillation frequency, the conventional tuning-fork type piezoelectric vibrating piece is formed with an oscillation frequency lower than the target frequency, and the metal formed at the tip of the vibrating arm is sublimated with laser light or the like. The oscillation frequency is increased to approach the target frequency.

  For example, as shown by the dotted line in FIG. 6, most of the tuning fork type piezoelectric vibrating reeds are formed at an oscillation frequency lower than the lower limit value TH1 before the oscillation frequency adjustment step. For this reason, it is necessary to adjust the frequency of most tuning-fork type piezoelectric vibrating pieces. Although FIG. 6 will be described later, FIG. 6 is a graph showing variations in individual oscillation frequencies when a tuning fork type piezoelectric vibrating piece is formed. The horizontal axis represents the oscillation frequency of the tuning fork type piezoelectric vibrating piece. Yes, the vertical axis indicates the number of tuning-fork type piezoelectric vibrating pieces.

  For example, in Patent Document 1, in both the coarse adjustment process and the fine adjustment process, the metal at the tip of the vibrating arm of the tuning fork type piezoelectric vibrating piece in the package is sublimated, and the tuning fork type piezoelectric lower than the target frequency. A method for increasing the frequency of the resonator element is disclosed.

JP 2002-164759 A

  However, when a tuning fork type piezoelectric vibrating piece exceeding the upper limit value TH2 of the target frequency shown in FIG. 6 is formed when the tuning fork type piezoelectric vibrating piece is formed, the upper limit value TH2 particularly in the conventional coarse adjustment process. The tuning-fork type piezoelectric vibrating piece exceeding the limit was impossible to adjust and had to be discarded. In addition, since most tuning fork type piezoelectric vibrating reeds are formed lower than the lower limit value TH1, the tuning frequency must be adjusted to be higher than that of most tuning fork type piezoelectric vibrating reeds on a wafer basis. However, the adjustment process of the oscillation frequency takes time, and the productivity of the tuning-fork type piezoelectric vibrating piece has been reduced.

  According to the present invention, when a tuning fork type piezoelectric vibrating piece is formed on a wafer basis, the tuning fork type piezoelectric vibrating piece designed at a target frequency is formed. Further, due to variations in the shape of the tuning fork type piezoelectric vibrating piece or the thickness of the excitation electrode, the tuning fork type piezoelectric vibrating piece formed lower than the lower limit value TH1 of the target frequency or higher than the upper limit value TH2 of the target frequency is formed. A tuning fork type piezoelectric vibrating piece adjustment method is provided that adjusts the tuning fork type piezoelectric vibrating piece to a target frequency for each wafer. That is, by forming a plurality of tuning-fork type piezoelectric vibrating pieces formed on a wafer basis at a target frequency, a large number of tuning-fork type piezoelectric vibrating pieces that substantially match the target frequency are formed. Therefore, it is possible to reduce the number of tuning-fork type piezoelectric vibrating pieces that require frequency adjustment. Further, the frequency can be adjusted on a wafer basis even for a tuning-fork type piezoelectric vibrating piece that exceeds the lower limit value TH1 or the upper limit value TH2 of the target frequency.

  According to a first aspect of the frequency adjustment method, the frequency of a tuning fork type piezoelectric vibrating piece is adjusted to a target frequency with respect to a piezoelectric wafer in which a plurality of tuning fork type piezoelectric vibrating pieces having a pair of vibrating arms extending from a base portion are integrally connected. This is a frequency adjustment method. This method includes a step of forming a first metal on at least a part of a frequency adjusting portion formed at a tip of a vibrating arm, a step of measuring a frequency of a tuning fork type piezoelectric vibrating piece coupled to a piezoelectric wafer, and a measurement When the frequency of the tuning fork type piezoelectric vibrating piece is lower than the target frequency, the first metal formed in the frequency adjusting unit is scraped, and the measured frequency of the tuning fork type piezoelectric vibrating piece is higher than the target frequency. In some cases, the method includes a frequency adjustment step of sublimating a second metal disposed away from the tuning-fork type piezoelectric vibrating piece and attaching the second metal to the frequency adjustment unit.

  The frequency adjustment method according to the second aspect is the frequency adjustment method according to the first aspect, in which the frequency adjustment is performed when the measured frequency of the tuning-fork type piezoelectric vibrating piece falls within the threshold value of the target frequency. Skip the process.

  A frequency adjusting method according to a third aspect is the frequency adjusting method according to the first aspect or the second aspect, wherein the step of measuring the frequency measures the frequency of a plurality of tuning-fork type piezoelectric vibrating pieces coupled to the piezoelectric wafer. At the same time, the address and frequency of the tuning fork type piezoelectric vibrating piece are stored, and the frequency adjusting step adjusts the frequency of the tuning fork type piezoelectric vibrating piece to the target frequency based on the stored address and frequency.

  A frequency adjustment method according to a fourth aspect is the frequency adjustment method according to any one of the first aspect to the third aspect, wherein the frequency adjustment step is to irradiate the first metal formed in the frequency adjustment unit with laser light. The first metal is scraped off and the second metal is irradiated with laser light to sublimate the second metal.

  A frequency adjustment method according to a fifth aspect is the frequency adjustment method according to the fourth aspect, wherein the first metal is formed on at least one surface of the frequency adjustment unit, and the frequency adjustment step is performed on the first surface of the first surface. The metal is irradiated with laser light, and the second metal is attached to the other surface opposite to the one surface.

The frequency adjustment method according to the sixth aspect is a frequency adjustment step in the frequency adjustment method according to the fifth aspect. On the other surface side, a length equal to or shorter than the length of the metal wafer having the second metal formed on one side and the extending direction of the vibrating arm of the frequency adjusting unit disposed between the metal wafer and the piezoelectric wafer. A mask formed with an opening having
When the second metal is attached to the other surface, the laser light moves relative to the piezoelectric wafer and the metal wafer, and the second metal on the metal wafer is irradiated with the laser light. Adheres to the other surface of the frequency adjusting unit through the opening.

  A frequency adjustment method according to a seventh aspect is the frequency adjustment method according to the fourth aspect, wherein the first metal is formed on at least one surface of the frequency adjustment unit, and the frequency adjustment step is performed on the first surface of the first surface. The metal is irradiated with laser light, and the second metal is attached to one surface.

  The frequency adjustment method according to the eighth aspect is a frequency adjustment step in the frequency adjustment method according to the seventh aspect. On one surface side, a metal wafer in which the second metal is formed on one side of the transparent plate through which the laser beam passes, and a direction in which the vibrating arm of the frequency adjusting unit extends between the metal wafer and the piezoelectric wafer. And a mask formed with an opening having a length equal to or shorter than the length of the first metal, the second metal is retracted when the first metal is irradiated with laser light, and the second metal is disposed on one surface. When the laser beam is attached, the laser beam moves relative to the piezoelectric wafer and the metal wafer, and the laser beam is irradiated onto the metal wafer, so that the second metal passes through the opening on one surface of the frequency adjusting unit. Adhere to.

  According to the present invention, when tuning fork type piezoelectric vibrating pieces are formed on a wafer basis, most tuning fork type piezoelectric vibrating pieces are formed at a target frequency. There are fewer piezoelectric vibrating pieces. Therefore, considering the adjustment time of the oscillation frequency in units of wafers, the time required for adjustment of the oscillation frequency can be shortened, and the throughput is improved. Further, since the oscillation frequency can be adjusted even for a tuning fork type piezoelectric vibrating piece higher than the upper limit value TH2 of the oscillation frequency, an unusable tuning fork type piezoelectric vibrating piece is not generated.

It is the whole structure of the frequency adjusting device 100a. 2 is a top view of a crystal wafer 200. FIG. FIG. 4A is a perspective view of the first metal wafer 300. FIG. (B) is an expanded sectional view in the AA cross section of (a). 3 is a top view of a mask wafer 400. FIG. 3 is a plan view showing one tuning-fork type crystal vibrating piece 20a formed on a quartz wafer 200. FIG. It is a graph which showed the dispersion | variation in frequency. (A) is the top view seen from the upper side which expanded and showed the vibrating arm 21 of the tuning fork type | mold crystal vibrating piece 20a at the time of arrange | positioning each wafer close. (B) is BB sectional drawing of (a). It is the figure which showed control of the frequency adjusting device 100a. It is a flowchart of the frequency adjustment process of the frequency adjustment apparatus 100a. It is the figure which showed the frequency adjusting device 100b. FIG. 4A is a bottom view of the second metal wafer 310. FIG. (B) is CC sectional drawing of (a). 3 is a plan view showing one tuning-fork type crystal vibrating piece 20b formed on a quartz wafer 200. FIG. (A) is an enlarged view of the tip portion of the vibrating arm 21 of the tuning-fork type crystal vibrating piece 20b when the wafers are stacked. (B) is DD sectional drawing of (a). This is an overall configuration when a third metal wafer 320 is used in the frequency adjusting device 100a. (A) is a layout view of the tip portion of the vibrating arm 21 of the tuning-fork type crystal vibrating piece 20b as viewed from the top of the third metal wafer 320 when the respective wafers are stacked. (B) is EE sectional drawing of (a).

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following embodiments, the direction in which the vibrating arm extends is the Y-axis direction, the arm width direction of the vibrating arm is the X-axis direction, and the direction perpendicular to the Y-axis and the X-axis direction is the Z-axis direction.

(First embodiment)
<Overall Configuration of Frequency Adjustment Device 100a>
FIG. 1 shows the overall configuration of a frequency adjusting apparatus 100a according to the present invention. The frequency adjusting device 100a of the present invention is a device that adjusts the oscillation frequency for hundreds to thousands of individual tuning-fork type crystal vibrating pieces 20a formed on the crystal wafer 200.

  The frequency adjustment device 100a includes a laser generation device 70 that generates laser light LA, a first XY table 80 on which a wafer is placed, a control unit 90, and a frequency measurement unit 95 that measures the oscillation frequency of the tuning-fork type crystal vibrating piece 20a. The The first metal wafer 300 is placed on the first XY table 80, and the mask wafer 400 is placed on the upper side (+ Z axis side). The crystal wafer 200 is placed on the upper side of the mask wafer 400. In FIG. 1, the wafers are illustrated so as to be separated from each other for easy understanding, but in actuality, the wafers are arranged in a state where the wafers are in contact with each other or close to each other.

  The laser generator 70 uses a femtosecond laser or the like that is easy to finely control. The laser generator 70 irradiates the laser beam LA according to an instruction from the control unit 90. Further, the control unit 90 rotates the galvanometer mirror 71 to change the irradiation position of the laser beam LA directed toward the first XY table 80 within a predetermined range. Instead of the galvanometer mirror 71, the laser generator 70 itself may be moved to change the irradiation position of the laser beam LA within a predetermined range.

  The first XY table 80 includes a table and a drive unit. The table is movable in the X-axis direction and the Y-axis direction as indicated by the arrows, and the drive unit (not shown) moves the table in the X-axis direction and the Y-axis direction by a signal from the control unit 90.

  The control unit 90 of the frequency adjusting device 100a controls the laser generator 70, the galvanometer mirror 71, and the first XY table 80, and adjusts the oscillation frequency by irradiating a predetermined position with the laser beam LA having a predetermined irradiation amount. . The controller 90 will be described later.

  The frequency measuring unit 95 individually measures the tuning fork type crystal vibrating piece 20 a formed on the crystal wafer 200. An excitation electrode is formed on the tuning-fork type crystal vibrating piece 20a, and the probe of the frequency measuring unit 95 can be in contact with the extraction electrode extracted from the excitation electrode. The frequency measuring unit 95 measures the oscillation frequency of each tuning-fork type crystal vibrating piece 20 a connected to the crystal wafer 200 and sends the measured oscillation frequency to the control unit 90.

  Since the crystal wafer 200 and the mask wafer 400 need an accurate positional relationship, they are adjusted based on the orientation flat formed on each wafer. Note that although the orientation flat is used as the reference position in the present embodiment, the reference position may be determined using another method such as a notch. In addition, the first metal wafer 300 according to the present embodiment does not need to identify the reference position, and therefore does not need to form an orientation flat, but has the same shape as the crystal wafer 200 and the mask wafer 400 so as to be easily transported and fixed. It is formed with.

Hereinafter, the crystal wafer 200, the first metal wafer 300, and the mask wafer 400 placed on the first XY table 80 will be described with reference to FIGS.
<Configuration of Quartz Wafer 200>
FIG. 2 is a top view of the crystal wafer 200 with the tuning fork type crystal vibrating piece 20a. The quartz wafer 200 is composed of a uniform flat plate Z-cut artificial quartz. The circular crystal wafer 200 has a thickness of, for example, 0.12 mm, and the crystal direction of the crystal is specified in a part of the peripheral portion of the crystal wafer 200 so that the axial direction of the circular crystal wafer 200 can be specified. An orientation flat OF is formed. The quartz fork crystal vibrating piece 20a is formed on the quartz wafer 200 by using a known etching technique and sputtering technique.

  The quartz wafer 200 is provided with a plurality of windows 210 in relation to process management and wafer strength, and a plurality of tuning fork type crystal vibrating pieces 20 a are formed in the windows 210. In each window part 210, a connecting part 28 is formed to connect the crystal wafer 200 and the tuning-fork type crystal vibrating piece 20a. The position of each tuning fork type crystal vibrating piece 20a and the position of each window part 210 are defined with reference to the orientation flat OF. The tuning fork type crystal vibrating piece 20a will be described later.

<Configuration of First Metal Wafer 300>
FIG. 3A is a perspective view of the first metal wafer 300. FIG. 3B is an enlarged cross-sectional view taken along the line AA in FIG. The first metal wafer 300 is used to sublimate metal particles to the tuning-fork type crystal vibrating piece 20a of the crystal wafer 200 by irradiation with laser light LA (see FIG. 1).

  The first metal wafer 300 includes a transparent or opaque uniform flat base 301 and a second metal film 302. The first metal wafer 300 is formed in the same size as the outer shape of the quartz wafer 200. A second metal film 302 is formed on the entire surface of the base 301.

  As shown in FIG. 3B, the first metal wafer 300 has a second metal film 302 formed on the upper surface side (mask wafer 400 side) of the base 301. The second metal film 302 is made of a material that can be sublimated by the laser beam LA and adhere to a predetermined portion, for example, gold (Au) or silver (Ag). The base 301 is formed of a transparent or opaque metal plate.

<Configuration of Mask Wafer 400>
FIG. 4 is a top view of the mask wafer 400. The mask wafer 400 is composed of a uniform flat plate. The mask wafer 400 is formed in the same size as the outer shape of the crystal wafer 200, and an opening 401 is formed at a predetermined position. In FIG. 4, the window 210 and the tuning-fork type crystal vibrating piece 20a of the crystal wafer 200 are indicated by broken lines in order to facilitate understanding of the position where the opening 401 is formed.

  The mask wafer 400 prevents the second metal film 302 of the first metal wafer 300 from scattering outside the opening 401. Further, the mask wafer 400 can prevent unnecessary metal particles from being scattered with respect to the adjacent tuning-fork type crystal vibrating piece 20a. On the other hand, the opening 401 allows the sublimating metal particles to pass therethrough and adhere the metal particles to the target portion of the tuning fork type crystal vibrating piece 20a. Note that the material constituting the mask wafer 400 is not particularly defined.

<Configuration of tuning fork type crystal vibrating piece 20a>
FIG. 5 is a plan view showing one tuning-fork type crystal vibrating piece 20 a formed on the crystal wafer 200. The tuning-fork type crystal vibrating piece 20a shown in the first embodiment includes a base portion 29 and a pair of vibrating arms 21 extending in parallel from one end of the base portion 29 in the Y-axis direction. The tuning fork type crystal vibrating piece 20a is designed with a target frequency THz of 32.768 kHz, for example.

  Grooves 22 are formed on both front and back surfaces of the vibrating arm 21 of the tuning fork type crystal vibrating piece 20a. Two grooves 22 are formed on the surface of one vibrating arm 21, and two grooves 22 are similarly formed on the back side of the vibrating arm 21. That is, four groove portions 22 are formed in the pair of vibrating arms 21. The groove portion 22 is provided to suppress an increase in the CI value of the tuning fork type crystal vibrating piece 20a.

  One connecting portion 28 is provided at the other end of the base 29 of the tuning fork type crystal vibrating piece 20a (the opposite side of the pair of vibrating arms 21). The connecting portion 28 is a portion that connects the crystal wafer 200 and the tuning-fork type crystal vibrating piece 20a.

  Excitation electrodes 23 are formed on the vibrating arm 21 and the base 29 of the tuning fork type crystal vibrating piece 20a. As the excitation electrode 23, a gold (Au) layer is formed on a chromium (Cr) layer by using a known sputtering technique or the like.

  A first metal film 24 (241, 242) is formed at the tip of the vibrating arm 21. The first metal film 24 (241, 242) is formed separately at two locations with respect to one vibrating arm 21. The first metal film 24 has a role of a weight and a role of a frequency adjustment unit for the purpose of increasing the oscillation frequency. The role of the weight is to make the vibrating arm 21 easy to vibrate and to maintain stable vibration when an alternating voltage is applied to the tuning fork type crystal vibrating piece 20a.

  The first metal film 24 may be formed of the same material as the excitation electrode 23 at the same time. Further, since the first metal film 24 functions as a weight, it may be formed thicker than the excitation electrode 23. A region sandwiched between the first metal film 241 and the second metal film 241 is a second metal formation region 25 to which the second metal film 302 (see FIG. 3) is attached.

  By separating the first metal film 24 into the first metal film 241 and the first metal film 242, the coarse adjustment and the fine adjustment are performed. For example, the first metal film 242 on the distal end side of the vibrating arm 21 can be used for coarse adjustment, and the first metal film 241 on the base side can be used for fine adjustment. In order to increase the oscillation frequency of the tuning fork type crystal vibrating piece 20a, the first metal film 24 formed on the vibrating arm 21 of the tuning fork type crystal vibrating piece 20a is removed.

  The second metal formation region 25 serves as a frequency adjustment unit for the purpose of lowering the oscillation frequency. The second metal formation region 25 is a region where the first metal film 24, the excitation electrode 23, and the like are not formed, and is simply a region where the base crystal is exposed. For this reason, the second metal formation region 25 is transparent and has a structure in which the laser beam LA (see FIG. 1) and the like easily pass.

  By irradiation with the laser beam LA or the like, the second metal film 302 disposed below the second metal formation region 25 is sublimated as metal particles, and is sublimated to one surface of the second metal formation region 25 (the vibrating arm 21 on the −Z axis side). ). By forming metal particles as the sublimation metal film 303 (see FIG. 7B) in the second metal formation region 25, the weight of the tip of the vibrating arm 21 is increased, and the oscillation frequency of the tuning fork type crystal vibrating piece 20a is increased. Descend.

<Frequency adjustment method>
The tuning fork type crystal vibrating piece 20a of the first embodiment is designed to have a target frequency THz. FIG. 6 is a graph showing variations in individual oscillation frequencies when the tuning-fork type crystal vibrating piece 20a is formed on one crystal wafer 200. FIG. The horizontal axis represents the oscillation frequency of the tuning fork type crystal vibrating piece 20a, and the vertical axis represents the number of tuning fork type crystal vibrating pieces 20a that vibrate at the oscillation frequency. The target frequency THz is, for example, 32.768 kHz, and the allowable range as the tuning fork type crystal vibrating piece 20a is from the lower limit value TH1 to the upper limit value TH2.

  Hundreds to thousands of tuning-fork type crystal vibrating pieces 20 a are formed on the crystal wafer 200. Due to variations in crystal etching when forming the outer shape of the tuning fork type crystal vibrating piece 20a and variations in the sputtering process for forming the excitation electrode, the oscillation frequency of the actually formed tuning fork type crystal vibrating piece 20a varies. End up.

  In the present embodiment (not only the first embodiment but also the second embodiment and the third embodiment described below), the tuning fork type crystal vibrating piece 20a is designed to have a target frequency THz. In the present embodiment, as shown by the solid line in FIG. 6, the tuning fork type crystal vibrating piece 20a before the coarse adjustment of the oscillation frequency is formed with many tuning fork type crystal vibrating pieces 20a excited around the target frequency THz. For this reason, many tuning-fork type crystal vibrating pieces 20a formed on the quartz wafer 200 do not need to be subjected to coarse frequency adjustment. It should be noted that the tuning fork type crystal vibrating piece 20a formed at a low oscillation frequency exceeding the lower limit TH1 of the allowable range is increased, and the tuning fork type crystal formed at a high oscillation frequency exceeding the upper limit TH2. The oscillation frequency is lowered with respect to the vibrating piece 20a. In this embodiment, since the oscillation frequency can be adjusted for the tuning fork type crystal vibrating piece 20a, the number of tuning fork type crystal vibrating pieces that are wasted can be reduced.

  The frequency adjustment device 100a according to the present embodiment performs adjustment to increase the oscillation frequency for the tuning fork type crystal vibrating piece 20a that is lower than the lower limit value TH1 of the target frequency THz, and the tuning fork type crystal vibration that exceeds the upper limit value TH2 of the target frequency THz. Adjustment is made to lower the oscillation frequency with respect to the piece 20a. The oscillation frequency can be lowered by simply making a simple change to the conventional frequency adjustment device.

  In this embodiment, it is necessary to adjust the frequency to lower the oscillation frequency. However, as can be understood from the solid line in FIG. 6, most of the tuning-fork type crystal vibrating pieces 20a are within the allowable range, and the frequency adjustment for the crystal wafer 200 is performed. Such time is shortened. Therefore, the throughput for producing one tuning fork type crystal vibrating piece 20a is improved.

  FIG. 7 shows a state in which the quartz wafer 200, the mask wafer 400 and the first metal wafer 300 are stacked close to each other, and is an enlarged view of the tip portion of the vibrating arm 21 of the tuning-fork type quartz vibrating piece 20a. FIG. 7A is a top view, and FIG. 7B is a sectional view taken along line BB in FIG.

  As shown in FIG. 7A, in the frequency adjustment step, the first metal wafer 300, the mask wafer 400, and the crystal wafer 200 are arranged in close proximity in order from the bottom. When viewed from the quartz wafer 200 side, the vibrating arm 21 of the tuning fork type quartz vibrating piece 20a can be seen. The mask wafer 400 and its opening 401 can be seen around the vibrating arm 21. The second metal film 302 of the first metal wafer 300 can be seen from the opening 401.

  As shown in FIGS. 5 and 7B, the first metal film 242, the second metal formation region 25, and the first metal film 241 are formed in this order from the tip on the vibrating arm 21 of the tuning-fork type crystal vibrating piece 20 a. Has been. An opening 401 of the mask wafer 400 is provided below the second metal formation region 25, and a first metal wafer 300 on which a second metal film 302 is formed is disposed below the opening 401.

  When the laser beam LA is irradiated onto the position of the first metal film 241 and the first metal film 242 from above the tuning fork type crystal vibrating piece 20a, the first metal film 24 is sublimated. When the laser beam LA is irradiated onto the position of the second metal formation region 25 from above the tuning-fork type crystal vibrating piece 20a, the laser beam LA passes through the crystal of the transparent second metal formation region 25, and further the mask wafer. It passes through 400 openings 401. Then, the laser beam LA sublimates the second metal film 302. The sublimated metal particles adhere to the second metal formation region 25 and form a sublimation metal film 303.

  This will be described more specifically. When increasing the frequency, the irradiation position of the laser beam LA is relatively disposed on the first metal film 24. For example, the irradiation position is adjusted by shaking the galvanometer mirror 71 (see FIG. 1).

  For example, the first metal film 242 is sublimated by irradiating the first irradiation position L1 with the laser beam LA. In FIG. 7B, the first metal film 242 at the first irradiation position L1 is sublimated to form a predetermined removal area. A removal area having a diameter of, for example, about 20 μm can be formed on the first metal film 24 by one irradiation with the laser beam LA. By forming the predetermined removal area of the first metal film 242, the oscillation frequency of the tuning fork type crystal vibrating piece 20a is increased by about 2 to 4 ppm, for example.

  By irradiating the second irradiation position L2 with the laser beam LA, the first metal film 241 near the base 29 (see FIG. 5) is sublimated. By forming the predetermined removal area of the first metal film 241, the oscillation frequency of the tuning fork type crystal vibrating piece 20a is increased by about 1 to 2 ppm, for example.

  That is, the tuning-fork type crystal vibrating piece 20a below the lower limit value TH1 shown in FIG. 6 removes the first metal film 241 and the first metal film 242 by measuring the deviation amount from the target frequency THz in advance. The position of the area and the number of times of irradiation with the laser beam LA can be obtained, and the frequency can be adjusted within the allowable range of the target frequency THz.

  When the frequency is lowered, the irradiation position of the laser beam LA is relatively arranged on the upper part of the second metal formation region 25. For example, when the laser beam LA is irradiated to the third irradiation position L 3, the laser beam LA passes through the transparent second metal formation region 25, and further passes through the opening 401 of the mask wafer 400. Is sublimated. The sublimated metal particles pass through the opening 401 of the mask wafer 400 and adhere to the second metal formation region 25 to form a sublimation metal film 303. With one irradiation of the laser beam LA, the oscillation frequency of the tuning fork type crystal vibrating piece 20a is lowered by, for example, about 1 to 2 ppm.

  That is, the tuning-fork type crystal vibrating piece 20a exceeding the upper limit value TH2 shown in FIG. 6 measures the deviation amount with respect to the target frequency THz in advance, so that the laser beam LA irradiated to the second metal formation region 25 is measured. The number of irradiations and the position can be obtained, and the frequency can be adjusted within the allowable range of the target frequency THz.

  The opening 401 of the mask wafer 400 prevents the metal particles from scattering outside the second metal formation region 25. This is because if the sublimated metal particles adhere to the excitation electrode 23, the tuning fork type crystal vibrating piece 20a may be short-circuited or the CI value may be increased. The size of the opening 401 may be a large area including the first metal film 241 and the first metal film 242. If the metal particles sublimated from the second metal film 302 do not adhere to the excitation electrode 23, the mask wafer 400 may be omitted.

<Control of frequency adjusting device 100a>
FIG. 8 is a diagram showing the control of the frequency adjusting device 100a. The control unit 90 of the frequency adjustment device 100a includes a control device 91 and a storage device 92.

  The control unit 90 moves the first XY table 80 in the X-axis direction or the Y-axis direction, and moves each tuning fork type crystal vibrating piece 20 a directly below the frequency measurement unit 95. Then, the frequency measuring unit 95 presses the probe against each tuning-fork type crystal vibrating piece 20a and measures their oscillation frequency. The measured oscillation frequency is recorded in the storage device 92 of the control unit 90 together with the position information of the tuning fork type crystal vibrating piece 20a. The controller 90 extracts the tuning-fork type crystal vibrating piece 20a that is outside the allowable range of the target frequency THz based on the information in the storage device 92. Further, in order to bring the oscillation frequency of the tuning-fork type crystal vibrating piece 20a close to the target frequency, the position of the first metal film 24 or the second metal film 302 to be irradiated with the laser light LA is determined.

  Further, the control unit 90 controls the laser generator 70 to irradiate the laser beam LA with a predetermined output for a predetermined time. In addition, the control unit 90 controls the galvanometer mirror 71 so as to irradiate the laser beam LA to a predetermined location. In the first embodiment, the laser beam LA is irradiated from a position perpendicular to the first metal wafer 300. By irradiating the laser beam LA from an oblique direction, the vibration of the tuning-fork type crystal vibrating piece 20a is vibrated. The second metal film 302 may be irradiated with the laser beam LA without passing through the arm 21.

<Frequency adjustment process>
The tuning fork type crystal vibrating piece 20a of the first embodiment is designed to have a target frequency THz, and the oscillation frequency is adjusted with respect to the tuning fork type crystal vibrating piece 20a outside the allowable range of the target frequency THz.

  In order to adjust the frequency in the frequency adjusting step, the frequency measuring unit 95 measures the frequencies of all the tuning fork type crystal vibrating pieces 20a formed on the crystal wafer 200 in advance. The frequency measuring unit 95 measures the oscillation frequency of each tuning-fork type crystal vibrating piece 20a by applying an alternating voltage while the probe of the frequency measuring unit 95 is in contact with the extraction electrode extracted from the excitation electrode.

  The measured value of the frequency of each tuning fork type crystal vibrating piece 20a is recorded together with the position information of the tuning fork type crystal vibrating piece 20a on the crystal wafer 200 and stored in the storage device 92 of the frequency adjusting device 100a. The position information of the tuning fork type crystal vibrating piece 20a is, for example, the position information of the window 210 of the crystal wafer 200 with reference to the orientation flat, the position information of the tuning fork type crystal vibrating piece 20a therein, and the tuning fork type crystal vibrating piece. The position information of the first metal film 24 formed on the vibrating arm 21 of 20a, the position information of the second metal formation region 25, and the like are included.

  The frequency adjustment device 100a adjusts the oscillation frequency for the tuning-fork type crystal vibrating piece 20a outside the allowable range of the target frequency THz from the measurement value of the frequency measurement unit 95. The frequency adjusting device 100a is arranged so that the target first metal film 24 falls within the irradiation range of the laser beam LA with respect to the tuning-fork type crystal vibrating piece 20a that is lower than the lower limit value TH1 (see FIG. 6) of the target frequency THz. Let The laser sending device 70 irradiates the first metal film 24 with a predetermined number of laser beams LA. Then, the oscillation frequency is increased to fall within the allowable range of the target frequency THz.

  In addition, the frequency adjusting device 100a applies the second metal formation region 25 to the irradiation range of the laser beam LA with respect to the tuning-fork type crystal vibrating piece 20a exceeding the upper limit value TH2 (see FIG. 6) of the target frequency THz. Arrange to be. The second metal film 302 of the first metal wafer 300 is irradiated with the laser beam LA a predetermined number of times. Then, the oscillation frequency is lowered to fall within the allowable range of the target frequency THz.

FIG. 9 is a flowchart of the frequency adjustment process of the frequency adjustment device 100a.
In step S11, a quartz wafer 200 having a plurality of tuning fork type quartz vibrating pieces 20a in which the first metal film 24 is formed on the vibrating arm 21 serving as a frequency adjusting unit is prepared.
In step S12, the control unit 90 of the frequency adjusting device 100a measures the oscillation frequency of each tuning-fork type crystal vibrating piece 20a by the frequency measuring unit 95, and acquires the frequency information and position information. The oscillation frequency and position information of each tuning fork type crystal vibrating piece 20a is stored in the storage device 92 of the control unit 90 of the frequency adjusting device 100a.

  In step S13, the control unit 90 determines whether the acquired frequency of the tuning-fork type crystal vibrating piece 20a is within an allowable range of the target frequency THz. If the frequency of the tuning fork type crystal vibrating piece 20a is within the allowable range of the target frequency THz, the process proceeds to step S16. If the frequency of the tuning fork type crystal vibrating piece 20a is below the lower limit value TH1 of the allowable range of the target frequency THz, the process proceeds to step S14. If the frequency of the tuning fork type crystal vibrating piece 20a exceeds the upper limit value TH2 of the allowable range of the target frequency THz, the process proceeds to step S15.

  In step S14, the control unit 90 moves the target tuning fork type crystal vibrating piece 20a to the target tuning fork type crystal vibrating piece 20a by the first XY table 80 so that the first metal film 24 of the tuning fork type crystal vibrating piece 20a enters the irradiation range of the laser beam LA. . Then, the laser generator 70 irradiates the predetermined portion of the first metal film 24 with the laser beam LA, thereby sublimating the first metal film 24 and adjusting the oscillation frequency.

  In step S15, the control unit 90 moves the target tuning fork type crystal vibrating piece 20a to the target XY table 80 so that the second metal forming region 25 falls within the irradiation range of the laser beam LA. The laser generator 70 irradiates a predetermined portion of the second metal formation region 25 with the laser beam LA. The laser beam LA passes through the second metal formation region 25, sublimates the second metal film 302, and forms a sublimation metal film 303 in the second metal formation region 25, thereby adjusting the oscillation frequency.

  In step S16, the control unit 90 of the frequency adjusting device 100a determines whether all the oscillation frequencies of the tuning-fork type crystal vibrating piece 20a that require frequency adjustment have been adjusted. If there is an unadjusted tuning fork type crystal vibrating piece 20a, the control unit 90 of the frequency adjusting device 100a returns to Step S12, and if not, ends the frequency adjusting process.

  Although not shown in the flowchart, the oscillation frequency of the tuning-fork type crystal vibrating piece 20a whose frequency is adjusted may be measured again to determine whether it is within the allowable range.

(Second Embodiment)
In the first embodiment, the laser beam LA is irradiated from the upper side (+ Z axis side) of the quartz wafer 200, and the first metal film 24 (first metal films 241 and 242) on the upper surface (+ Z axis side) is removed. On the other hand, the sublimation metal film 303 was formed on the lower surface (−Z side) of the second metal formation region 25. A second metal formation region 25 is disposed between the first metal film 241 and the first metal film 242.

In the frequency adjusting device 100b of the second embodiment, the first metal film 24 on the upper surface (+ Z axis side) is removed, and the sublimation metal film 303 is also formed on the upper side (−Z side) of the second metal formation region 25. Further, it is not necessary for the laser beam LA to pass through the tuning fork type crystal vibrating piece. For this reason, all the tips of the vibrating arms 21 may be covered with the first metal film 24. That is, in the second embodiment, the first metal film 24 and the second metal formation region 25 may overlap.
Hereinafter, a different point from 1st Embodiment is demonstrated and the description is abbreviate | omitted using the same code | symbol about the same point.

  FIG. 10 is a diagram showing the frequency adjusting device 100b. As shown in FIG. 10, in the frequency adjusting device 100b, the crystal wafer 200 is placed on the first XY table 80, and the mask wafer 400 is placed thereon. A second metal wafer 310 is disposed on the second XY table 85 that can be driven in the X-axis direction.

  The second XY table 85 includes a circular opening 86 and a moving mechanism. As shown in FIG. 10, the second XY table 85 has a circular opening 86 and is configured to hold the outer periphery of the second metal wafer 310.

  The moving mechanism of the second XY table 85 has a drive unit (not shown) that can move in the X-axis direction, and the movement amount in the X-axis direction is controlled by the control unit 90.

<Configuration of Mask Wafer 400>
The configuration of the mask wafer 400 is the same as that of the first embodiment, but the opening 401 is formed with a size equivalent to the width of the first metal film 24 in the Y-axis direction.

<Configuration of Second Metal Wafer 310>
The second metal wafer 310 is composed of a transparent uniform flat base 301 and a second metal film 302. In addition, the second metal wafer 310 is formed to have approximately the same size as the outer shape of the crystal wafer 200. The base 301 is made of a transparent material such as glass or plastic film. The second metal wafer 310 has an outer shape equivalent to that of the crystal wafer 200, but is fixed to the second XY table 85 and is movable, so that the shape or size of the outer shape is not limited. When the base 301 is made of glass or the like, gold (Au) or silver (Ag) may not be directly attached. In such a case, a second metal film 302 of gold (Au) or silver (Ag) may be formed on a base layer having high adhesion to glass such as nickel (Ni) or chromium (Cr). .

  The second metal wafer 310 is held at the outer periphery by a circular opening 86 formed in the outer shape of the second metal wafer 310, and can be moved in the X-axis direction and the Y-axis direction by a moving mechanism installed on the second XY table 85. It has become.

  FIG. 11 is a view showing the second metal wafer 310. FIG. 11A is a bottom view of the second metal wafer 310, and FIG. 11B is a cross-sectional view taken along the line C-C in FIG. The second metal wafer 310 is formed of a uniform flat plate, and the second metal film 302 is formed on the lower surface side (−Z axis direction).

  As shown in FIG. 11A, a second metal film 302 is formed on the second metal wafer 310 in a strip shape parallel to the Y-axis direction. The width (X-axis direction) of the band-shaped second metal film 302 is formed substantially the same as the width (X-axis direction) of the tuning-fork type crystal vibrating piece 20b (see FIG. 13A). Further, as shown in FIG. 11B, the second metal wafer 310 has a second metal film 302 formed on the base 301. The base 301 is made of a transparent material such as glass and film. For example, gold (Au) or silver (Ag) is used for the metal film of the second metal wafer 310. Further, the second metal film 302 is formed to have a width approximately equal to the width of the two vibrating arms 21 of the tuning fork type crystal vibrating piece 20b.

<Configuration of tuning fork type crystal vibrating piece 20b>
The tuning-fork type crystal vibrating piece 20b of the second embodiment has the same configuration as the tuning-fork type crystal vibrating piece 20a shown in the first embodiment, but the shape of the tip of the vibrating arm 21 has a certain width (X-axis direction). The tuning fork type crystal vibrating piece 20b of the vibrating arm 21 that is formed wide and has a so-called hammer-type wide portion will be described.

  FIG. 12 is a plan view showing one tuning-fork type crystal vibrating piece 20 b formed on the crystal wafer 200. The shape of the tip of the vibrating arm 21 of the tuning fork type crystal vibrating piece 20b is formed wider than the width (X-axis direction) of the vibrating arm 21 on the base side. The tuning fork type crystal vibrating piece 20b can reduce the length of the vibrating arm 21 by forming the tip of the vibrating arm 21 wide.

  A first metal film 24 is formed in the wide portion. The second metal formation region 25 of the second embodiment is the same as the region where the first metal film 24 is formed because the laser beam LA does not need to pass through the tuning fork type crystal vibrating piece. The structure of the other tuning fork type crystal vibrating piece 20b is the same as that of the tuning fork type crystal vibrating piece 20a shown in the first embodiment.

  FIG. 13 is a view in which the quartz wafer 200, the mask wafer 400, and the second metal wafer 310 are overlaid, and particularly an enlarged view of the tip portion of the vibrating arm 21 of the tuning fork type quartz vibrating piece 20a. FIG. 13A is a top view showing the positional relationship between the first metal film 24, the opening 401 of the mask wafer 400, and the second metal wafer 310. Originally, the lower side (−Z axis side) of the second metal film 302 is not visible, but a part of the vibrating arm 21 is indicated by a dotted line to help understanding. FIG.13 (b) is DD sectional drawing of (a). However, the drawing on the right side of the broken line of the second metal wafer 310 depicted in FIG. 13B shows the state after the second metal wafer 310 is moved in the X-axis direction.

  The tuning fork type crystal vibrating piece 20b has a wider frequency adjustment range because the formation region of the first metal film 24 and the second metal formation region 25 are wider than those of the first embodiment. That is, it is possible to cope with the case where the range from the lower limit value TH1 to the upper limit value TH2 of the target frequency THz shown in FIG. 6 is narrowed.

<Frequency adjustment method>
The frequency adjustment method is the same as in the first embodiment. To increase the frequency, the first metal film 24 formed on the vibrating arm 21 of the tuning-fork type crystal vibrating piece 20b is removed, and to decrease the frequency, A sublimation metal film 303 is formed in the two metal formation region 25 (overlapping with the region of the first metal film 24).

  As shown in FIG. 13A, the crystal wafer 200, the mask wafer 400, and the second metal wafer 310 are arranged in close proximity from the bottom. When these wafers are viewed from the second metal wafer 310 side (+ Z-axis side), the tip of the vibrating arm 21 of the tuning fork type crystal vibrating piece 20b is disposed below the metal film formed on the second metal wafer 310. The opening 401 of the mask wafer 400 is disposed so as to surround the region of the one metal film 24.

  In order to lower the frequency, the sublimation metal film 303 is formed in the region of the first metal film 24. For example, as shown in the drawing on the left side of the broken line in FIG. 13B, the first irradiation position L1 is irradiated with the laser beam LA, and the second metal film 302 of the second metal wafer 310 is sublimated. The sublimated metal particles of the second metal film 302 pass through the opening 401 of the mask wafer 400 and adhere to the first metal film 24 of the tuning-fork type crystal vibrating piece 20b. Then, a sublimation metal film 303 is formed.

  Further, when it is desired to increase the frequency, the first metal film 24 is sublimated. Specifically, first, the second metal wafer 310 is moved in the X-axis direction, and the second metal film 302 is retracted from the irradiation range of the laser light LA. For example, as shown in the drawing on the right side of the broken line in FIG. 13B, the second metal wafer 310 moves and the second metal film 302 is retracted from the irradiation path of the laser beam LA. As shown in FIG. 13A, the second metal film 302 is not disposed at the second irradiation position L2 of the laser beam LA.

  When the laser beam LA is irradiated at the second irradiation position L2, the laser beam LA passes through the transparent region of the second metal wafer 310 (the region where the second metal film 302 is not formed), and the opening of the mask wafer 400 The first metal film 24 is irradiated through 401. The first metal film 24 is sublimated by irradiation with the laser beam LA.

  The frequency adjustment step and the control unit 90 of the frequency adjustment device 100b are the same as those in the first embodiment. Further, the distance for moving the second metal wafer 310 in the X-axis direction can be short because the second metal film 302 is the tuning-fork type crystal vibrating piece 20b.

(Third embodiment)
Also in the third embodiment, the first metal film 24 on the upper surface (+ Z axis side) is removed, and the sublimation metal film 303 is also formed on the upper side (−Z side) of the second metal formation region 25. However, the third embodiment uses a third metal wafer 320 having a different second metal film 302 formed on the second metal wafer 310 shown in the second embodiment.

  In the third embodiment, the frequency adjustment device 100a shown in the first embodiment is used, and the tuning-fork type crystal vibrating piece 20b shown in the second embodiment is used. Hereinafter, differences from the second embodiment will be described, and the same reference numerals will be used for the same points and the description thereof will be omitted. The second metal formation region 25 of the third embodiment is also a region overlapping with the first metal film 24.

  FIG. 14 shows the overall configuration when the third metal wafer 320 is used in the frequency adjusting device 100a. As shown in FIG. 14, in the frequency adjusting device 100a of the third embodiment, a crystal wafer 200 is placed on a first XY table 80, a mask wafer 400 is placed thereon, and a third portion is placed thereon. A metal wafer 320 is disposed.

  The third metal wafer 320 is composed of a transparent uniform flat base 301 and a second metal film 302. The third metal wafer 320 is formed with the same size as the outer shape of the crystal wafer 200.

  The second metal film 302 formed on the third metal wafer 320 is formed in a strip shape as shown in FIG. Unlike the second embodiment, the second metal film 302 formed on the third metal wafer 320 is formed in parallel with the X-axis direction. The second metal film 302 parallel to the X-axis direction is arranged orthogonal to the vibrating arm 21 of the tuning fork type crystal vibrating piece 20b, and is arranged as shown in FIG.

  FIG. 15 is a view showing the arrangement of the second metal film 302 formed on the third metal wafer 320. FIG. 15A is a diagram in which the quartz wafer 200, the mask wafer 400, and the third metal wafer 320 are stacked, and is an enlarged view of the tip portion of the vibrating arm 21 of the tuning-fork type quartz vibrating piece 20a. FIG.15 (b) is EE sectional drawing of (a). As shown in FIG. 15A, the crystal wafer 200, the mask wafer 400, and the third metal wafer 320 are arranged in this order from the bottom.

  As shown in FIG. 15A, the second metal film 302 formed on the third metal wafer 320 is orthogonal to the vibrating arm 21 of the tuning-fork type crystal vibrating piece 20b, and the first metal formed on the vibrating arm 21. The film 24 is formed so as to cover and form a part of the film 24. The opening 401 of the mask wafer 400 is formed to have a size about the width of the first metal film 24 formed on the vibrating arm 21 in the Y-axis direction.

  In the frequency adjustment, the oscillation frequency can be increased or decreased at the position where the laser beam LA is irradiated. When it is desired to decrease the frequency, for example, as shown in FIG. 15B, the laser beam LA is irradiated to the first irradiation position L1, and the second metal film 302 of the third metal wafer 320 is irradiated with the laser beam LA. Sublimated. The sublimated metal particles of the second metal film 302 pass through the opening 401 of the mask wafer 400 and adhere to the first metal film 24 of the tuning-fork type crystal vibrating piece 20b.

Further, when it is desired to increase the frequency, the laser beam LA is irradiated to the second irradiation position L2. The second metal film 302 is not formed at this position. The laser beam LA can pass through the transparent region of the third metal wafer 320, pass through the opening 401 of the mask wafer 400, and sublimate the first metal film 24 formed on the tuning fork type crystal vibrating piece 20b. Become. The first metal film 24 is sublimated by irradiation with the laser beam LA, so that the removal area of the first metal film 24 can be formed and the frequency can be increased.
The other frequency adjustment steps and the control unit 90 of the frequency adjustment device 100a are the same as those in the first embodiment.

  As described above, the optimal embodiment of the present invention has been described in detail. However, as will be apparent to those skilled in the art, the present invention can be implemented with various modifications and variations within the technical scope thereof. For example, in the above-described embodiment, the frequency measuring unit 95 is arranged inside the frequency adjusting device 100. However, in another place, the frequency of the tuning-fork type crystal vibrating piece 20 in the crystal wafer 200 is measured in advance, The frequency information and position information of the tuning fork type crystal vibrating piece 20 may be transmitted to the storage device 92 of the frequency adjusting device 100.

20a, 20b ... tuning-fork type crystal vibrating piece 21 ... vibrating arm 22 ... groove 23 ... excitation electrode 24 (241, 242) ... first metal film 25 ... second metal forming region 28 ... coupling portion 29 ... base 70 ... laser generator 71 ... Galvano mirror 80 ... 1st XY table 85 ... 2nd XY table 86 ... Circular opening 90 ... Control part 91 ... Control apparatus 92 ... Memory | storage device 95 ... Frequency measurement part 100a, 100b ... Frequency adjustment apparatus 200 ... Quartz wafer 210 ... Window Part 300: first metal wafer 301: base (opaque or transparent)
302 ... 2nd metal film 303 ... Sublimation metal film 310 ... 2nd metal wafer 320 ... 3rd metal wafer 400 ... Mask wafer 401 ... Opening OF ... Orientation flat L1 ... 1st irradiation position L2 ... 2nd irradiation position LA ... Laser Light TH1 ... Lower limit value TH2 ... Upper limit value THz ... Target frequency

Claims (8)

In a frequency adjustment method for adjusting a frequency of the tuning fork type piezoelectric vibrating piece to a target frequency with respect to a piezoelectric wafer integrally connecting a plurality of tuning fork type piezoelectric vibrating pieces having a pair of vibrating arms extending from a base,
Forming a first metal on at least a part of the frequency adjusting portion formed at the tip of the vibrating arm;
Measuring the frequency of the tuning-fork-type piezoelectric vibrating piece coupled to the piezoelectric wafer;
When the measured frequency of the tuning-fork type piezoelectric vibrating piece is lower than the target frequency, the first metal formed on the frequency adjusting unit is scraped, and the measured frequency of the tuning-fork type piezoelectric vibrating piece is When the frequency is higher than the target frequency, a frequency adjustment step of sublimating the second metal disposed away from the tuning-fork type piezoelectric vibrating piece and attaching it to the frequency adjustment unit;
For adjusting the frequency of a tuning-fork-type piezoelectric vibrating piece comprising   The frequency of the tuning fork type piezoelectric vibrating piece according to claim 1, wherein the frequency adjustment step is skipped when the measured frequency of the tuning fork type piezoelectric vibrating piece falls within the threshold value of the target frequency. Adjustment method. The step of measuring the frequency measures the frequency of the plurality of tuning fork type piezoelectric vibrating pieces coupled to the piezoelectric wafer and stores the address and frequency of the tuning fork type piezoelectric vibrating piece,
The tuning fork type piezoelectric vibrating piece according to claim 1 or 2, wherein the frequency adjusting step adjusts the frequency of the tuning fork type piezoelectric vibrating piece to the target frequency based on the stored address and frequency. Frequency adjustment method.   In the frequency adjustment step, the first metal formed in the frequency adjustment unit is irradiated with laser light to scrape the first metal, and the second metal is irradiated with laser light to sublimate the second metal. The frequency adjustment method for a tuning-fork type piezoelectric vibrating piece according to any one of claims 1 to 3. The first metal is formed on at least one surface of the frequency adjustment unit,
The said frequency adjustment process irradiates the said laser beam with respect to the said 1st metal of said one surface, and adheres the said 2nd metal to the other surface on the opposite side of the said one surface. A method for adjusting the frequency of a tuning-fork type piezoelectric vibrating piece. In the frequency adjustment step, on the other surface side, the metal wafer having the second metal formed on one side thereof, and the vibration arm of the frequency adjustment unit disposed between the metal wafer and the piezoelectric wafer are disposed. A mask in which an opening having a length equal to or shorter than the length in the extending direction is formed,
When the second metal is attached to the other surface, the laser light moves relative to the piezoelectric wafer and the metal wafer, and the laser light irradiates the second metal on the metal wafer. The frequency adjusting method for a tuning-fork type piezoelectric vibrating piece according to claim 5, wherein the second metal adheres to the other surface of the frequency adjusting unit through the opening. The first metal is formed on at least one surface of the frequency adjustment unit,
5. The tuning-fork type piezoelectric vibrating piece according to claim 4, wherein the frequency adjusting step irradiates the first metal on the one surface with the laser light and attaches the second metal to the one surface. Frequency adjustment method. In the frequency adjustment step, the one surface side is disposed between the metal wafer having the second metal formed on one side of the transparent plate through which the laser beam passes, and the metal wafer and the piezoelectric wafer. A mask formed with an opening having a length equal to or shorter than the length of the vibrating arm of the frequency adjusting unit in the extending direction; and
When irradiating the laser beam to the first metal, the second metal is retracted,
When the second metal is attached to the one surface, the laser light moves relative to the piezoelectric wafer and the metal wafer, and the laser light is applied to the metal wafer, The frequency adjusting method for a tuning-fork type piezoelectric vibrating piece according to claim 7, wherein the second metal adheres to one surface of the frequency adjusting unit through the opening.