JP2014232965A - Crystal vibrator and manufacturing method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a crystal vibrator capable of reducing a crystal impedance value (CI value) and improving a vibration property, and to provide a crystal vibrator capable of improving rigidity of a vibration leg and also improving impulse resistance, the crystal vibrator comprising the vibration leg in which a plurality of grooves are formed.SOLUTION: In the crystal vibrator, an electrode is formed on a vibration piece including a base and a vibration leg protruding from the base. A plurality of grooves which are arranged side by side in a width direction of the vibration leg, are formed on a principal surface of the vibration leg and depths of the grooves are different. Further, the plurality of grooves arranged side by side in the width direction of the vibration groove on the principal surface of the vibration leg include three grooves of a center groove and outer grooves disposed at both sides of the center groove, and only the center groove is formed shallower than the outer grooves.

Description

The present invention relates to a crystal resonator having good vibration characteristics and high reliability used as a reference signal source for electronic devices such as mobile communication devices and smart meters and watches, and a method for manufacturing the same.
More specifically, the present invention relates to a tuning fork type crystal resonator in which grooves having different depths are formed in a vibrating leg and a method for manufacturing the same.

  Piezoelectric vibration devices such as vibrators, resonators, and oscillators are widely used as reference signal sources for watches and mobile communication devices. Among such piezoelectric vibration devices, crystal oscillators and crystal oscillators that use quartz as a piezoelectric material are in great demand because of their good temperature characteristics and high accuracy.

  Among crystal resonators, tuning fork type crystal resonators utilizing bending vibration and torsional vibration used in a low frequency band (several hundred kHz or less) are widely used in many products. Bending vibration is one of the vibration modes, and refers to a vibration mode in which the outer shape of the vibrating body is bent. On the other hand, torsional vibration is a vibration mode in which the outer shape of the vibrating body is twisted.

  Hereinafter, the structure of the most common tuning fork type crystal resonator will be described as a resonator using bending vibration or torsional vibration. FIG. 6 is a diagram showing the structure of a general tuning fork type crystal resonator.

  As shown in FIG. 6, a general tuning-fork type crystal resonator 11 is patterned in a desired shape on a vibrating piece 81 including a base 120 and two vibrating legs 113 and 114 protruding from the base 120. Electrodes 51 and 52 having different potentials are formed.

  Further, in recent years, a structure in which three grooves 130 are formed on the main surfaces of the vibrating legs 113 and 114 in order to keep the crystal impedance value (generally abbreviated as CI value for short) of the crystal unit 11 is widely known. (See, for example, Patent Document 1, Patent Document 2, and Patent Document 3). The CI value is a value that serves as an index of the ease of oscillation of the crystal resonator, and the smaller the value, the easier it is to oscillate.

  FIG. 7 is a cross-sectional view of a vibration leg of a conventional quartz resonator having three grooves. As shown in FIG. 7, the vibrating legs 113 and 114 are formed with three grooves 130 on one main surface and six in total on both sides. The groove depth d of the grooves 130 is generally formed with the same depth.

  Further, as shown in FIG. 7, an electrode 51 is formed on the inner wall of the groove 130 of the vibration leg 113, and an electrode 52 having a potential different from that of the electrode 51 is formed on the side wall of the vibration leg 113. On the other hand, an electrode 52 is formed on the inner wall of the groove 130 of the vibration leg 114, and an electrode 51 having a potential different from that of the electrode 52 is formed on the side wall of the vibration leg 114. In this way, by applying a voltage between the inner wall of the groove 130 and the side walls of the vibration legs 113 and 114 and alternately switching the potential, the vibration legs 113 and 114 made of quartz, which is a piezoelectric material, vibrate by electrostriction. To do.

  In addition, if the groove | channel 130 is deepened, the area of the inner wall of the groove | channel 130 will become large, and the electrode area can be enlarged correspondingly. As a result, since a larger electrostrictive effect can be obtained, the CI value can be lowered, and the vibrating legs 113 and 114 are likely to vibrate.

  FIG. 8 is a view showing a method of manufacturing a resonator element in which three grooves are formed on the main surface of a vibration leg used in a conventional crystal resonator. A conventional method for manufacturing a resonator element having the vibration legs 113 and 114 in which three grooves 130 are formed will be described below.

  First, as shown in FIG. 8A, a mask layer 30 is formed on both surfaces of a quartz wafer 20 having a predetermined thickness in a pattern that models the outer shape of the vibrating legs 113 and 114. In general, a laminated film in which the lower layer is made of chromium (Cr) and the upper layer is made of gold (Au) is often used as the mask layer 30. As a patterning method, a photolithography method capable of patterning a fine shape with high accuracy is often used.

  Next, as shown in FIG. 8B, a resist layer 42 in which three groove patterns for forming the grooves 130 are patterned on the mask layer 30 is formed. The three groove patterns patterned on the resist layer 42 are all formed with the same groove width a. In general, a photolithography method is often used as a patterning method for the resist layer 42.

  Thereafter, as shown in FIG. 8C, the crystal wafer 20 is etched with a chemical solution such as hydrofluoric acid using the mask layer 30 as a mask to form the vibrating legs 103 and 104. The upper Au film used as the mask layer 30 is very effective as a mask because it has corrosion resistance against hydrofluoric acid. The lower Cr film serves as an adhesion layer for preventing the Au film from peeling from the crystal wafer 20.

  Next, as shown in FIG. 8D, the mask layer 30 is etched using the resist layer 42 on which the groove pattern is formed as a mask, and the groove pattern having the same shape as the resist layer 42 is patterned. Layer 32 is formed.

  After that, as shown in FIG. 8E, the vibrating legs 103 and 104 are etched with a chemical solution such as hydrofluoric acid using the mask layer 32 with the groove pattern patterned as a mask to form the groove 130. Then, the vibration legs 113 and 114 having three grooves 130 formed on the main surface are formed. The three grooves 130 formed by etching have the same groove width and the same depth.

  Finally, as shown in FIG. 8 (f), the resist layer 42 and the mask layer 32 are peeled off, and the vibrating piece 81 having the vibrating legs 113 and 114 in which three grooves 130 are engraved on the main surface is completed.

JP 2004-135052 A Japanese Patent No. 4241022 JP 2012-156873 A

  In the crystal unit 11 having the conventional three grooves 130, it is desirable to form the groove 130 as deep as possible in order to keep the crystal impedance value (CI value) low. This is because when the groove 130 is deepened, the area of the inner wall of the groove 130 is increased, and the electrode area can be increased accordingly, and as a result, a larger electrostrictive effect can be obtained.

  Patent Documents 1 and 2 disclose a crystal resonator having a structure in which three grooves are formed in a vibration leg in order to increase the electrode area and reduce the CI value. As described above, in order to lower the CI value, it is desirable to make the three grooves deeper. On the other hand, if the groove depth is made deeper, the cross-sectional area of the vibrating leg becomes smaller and the rigidity becomes lower. As a result, when an impact is applied, the vibration leg is broken or cracked, which causes an oscillation failure. The three grooves disclosed in Patent Document 1 and Patent Document 2 are all grooves having the same depth, but the depth of the groove is not described in detail.

  Patent Document 3 discloses a structure in which only two outer grooves out of three grooves are short on the base side. That is, by adopting a structure in which only one central groove is formed on the base side of the vibration leg, the cross-sectional area on the base side of the vibration leg is widened to increase the rigidity. However, in this structure, only the base side of the vibrating leg has high rigidity, which is insufficient to increase the rigidity of the entire vibrating leg.

  In order to solve the above-mentioned problems, the crystal resonator of the present invention is characterized by having a groove shape as shown below.

  Specifically, in the crystal resonator in which an electrode is formed on a vibrating piece having a base and a vibrating leg protruding from the base, a plurality of grooves arranged in the width direction of the vibrating leg are formed on the main surface of the vibrating leg. The plurality of grooves are constituted by a central groove between the two outer grooves and the outer groove, and the central groove is characterized in that the depth of the groove is shallower than that of the outer groove.

  In addition, in order to solve the above-described problems, a method for manufacturing a crystal resonator according to the present invention is characterized by the following manufacturing method.

  Specifically, it is a method for manufacturing a crystal resonator in which an electrode is formed on a vibrating piece having a base, a vibrating leg that protrudes from the base, and a plurality of grooves that are formed on the main surface of the vibrating leg. Forming a mask layer having corrosion resistance patterned with a vibrating piece outer shape pattern having a vibrating leg outer shape pattern and a base outer shape pattern on the front and back surfaces of the quartz wafer, and etching the quartz wafer to form an outer shape of the vibrating piece. Forming a plurality of groove patterns having different widths in the mask layer after forming the outer shape of the resonator element, and forming grooves having different depths on the main surface of the vibration leg. It is characterized by having.

  Further, a method of manufacturing a crystal resonator in which an electrode is formed on a vibrating piece having a base, a vibrating leg protruding from the base, and a plurality of grooves formed on a main surface of the vibrating leg, Forming a mask layer having corrosion resistance by patterning a vibrating piece outer shape pattern having a vibrating leg outer shape pattern and a base outer shape pattern on the front and back surfaces of a quartz wafer and a plurality of groove patterns having different widths; and It is characterized in that it includes a step of etching the quartz wafer by using it as a mask and simultaneously forming the outer shape of the vibrating piece and grooves having different depths on the main surface of the vibrating leg.

  Further, the groove pattern formed in the mask layer is a three-groove pattern of a central groove pattern and an outer groove pattern disposed on both sides of the central groove pattern, and only the central groove pattern is grooved more than the outer groove pattern. It is characterized by a narrow width.

  The crystal resonator according to the present invention has a low CI value by making only the central groove out of the three grooves formed on the main surface of the vibration leg shallower than the outer grooves arranged on both sides of the central groove. A crystal unit with excellent characteristics, high vibration leg rigidity, and excellent shock resistance has been achieved.

  Furthermore, in the method for manufacturing a crystal resonator according to the present invention, three grooves are formed on the main surface of the vibration leg, and only the central groove of the three grooves is shallower than the outer grooves disposed on both sides of the central groove. As a result, it is possible to provide a crystal resonator having a low CI value and excellent vibration characteristics, and having a vibration leg with high rigidity and excellent impact resistance.

  Further, since grooves having different depths can be processed at the same time, productivity is also good.

It is sectional drawing of the vibration leg of the crystal oscillator which has three groove | channels of this invention. It is the figure which showed the structure of the crystal oscillator of this invention. It is the figure which showed an example of the manufacturing method of the vibration piece in which three groove | channels were formed in the main surface of the vibration leg used for the crystal oscillator of this invention. It is the figure which showed another example of the manufacturing method of the vibration piece in which three groove | channels were formed in the main surface of the vibration leg used for the crystal oscillator of this invention. It is sectional drawing of the vibration leg of the crystal oscillator which has four grooves of this invention. It is the figure which showed the structure of the conventional crystal oscillator. It is sectional drawing of the vibration leg of the conventional quartz oscillator which has three groove | channels. It is the figure which showed the manufacturing method of the vibration piece in which three grooves were formed in the main surface of the vibration leg used for the conventional crystal oscillator.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 2 is a diagram showing the structure of the crystal resonator of the present invention.

  As shown in FIG. 2, the crystal resonator 10 of the present invention has different potentials patterned in a desired shape on a vibrating piece 80 including a base 120 and two vibrating legs 111 and 112 protruding from the base 120. It has a structure in which the electrodes 51 and 52 are formed. The vibration legs 111 and 112 are formed with a total of three grooves including one central groove 132 and two outer grooves arranged on both sides of the main surface on the front and back sides. That is, a total of six grooves are formed on each vibrating leg, three on each side.

  FIG. 1 is a cross-sectional view of a vibrating leg of a crystal resonator having three grooves according to the present invention. As shown in FIG. 1, each of the vibrating legs 111 and 112 has one central groove 132 and two outer grooves 131 disposed on both sides thereof, three in total on one main surface and six in total on the front and back. It is formed one by one. The outer groove 131 is formed with a groove depth d1, while the central groove 132 is formed with a shallower groove depth d2 (<d1).

  Further, as shown in FIG. 1, an electrode 51 is formed on the inner wall of the outer groove 131 and the central groove 132 of the vibration leg 111, and an electrode 52 having a potential different from that of the electrode 51 is formed on the side wall of the vibration leg 111. ing. On the other hand, an electrode 52 is formed on the inner walls of the outer groove 131 and the central groove 132 of the vibration leg 112, and an electrode 51 having a potential different from that of the electrode 52 is formed on the side wall of the vibration leg 112. In this way, by applying a voltage between the inner wall of the outer groove 131 and the side walls of the vibrating legs 113 and 114 and switching the potentials alternately, the vibrating legs 111 and 112 made of quartz, which is a piezoelectric material, are electrostricted. Vibrate.

  When the groove depth d1 of the outer groove 131 is increased, the area of the inner wall of the outer groove 131 is increased, and the electrode area can be increased accordingly. As a result, since a larger electrostrictive effect can be obtained, the CI value can be lowered, and the vibrating legs 111 and 112 are likely to vibrate. However, if the groove depth d1 of the outer groove 131 is too deep, it becomes difficult to form the material constituting the electrodes 51 and 52 deep into the groove. There is.

  Further, by providing the central groove 132, the vibration legs 111 and 112 have low rigidity and are more easily vibrated. However, if the groove depth d2 of the central groove 132 is excessively deepened, there is an increased risk that the vibration leg may be broken or cracked due to an impact, so that the groove depth d2 of the central groove 132 is an appropriate depth. It is necessary to suppress it.

  For this reason, the optimum groove depth d1 of the outer groove 131 and the optimum groove depth d2 of the central groove 132 are different from each other. Therefore, like the crystal resonator 10 of the present invention, the groove depth of the outer groove 131 is different. The structure in which the groove depth d2 of the central groove 132 is shallower than d1 (d2 <d1) is very effective in achieving both excellent vibration characteristics and excellent impact resistance.

  In the present embodiment, an outer groove 131 having a groove depth d1 of 58 μm and a central groove 132 having a groove depth d2 of 53 μm are formed in each of the vibrating legs 111 and 112 having a thickness t of 128 μm. On the vibrating legs 111 and 112, electrode films 51 and 52 having a laminated structure in which a lower layer is a chromium (Cr) film having a thickness of 0.02 μm and an upper layer is a gold (Au) film having a thickness of 0.12 μm are formed.

  In the present embodiment, an example in which three grooves are formed on the vibrating leg is given. However, even when the number of grooves is four or more, the same effect can be obtained by shallowing the central groove. It is done. In the case of four or more grooves, grooves may be formed with three or more groove depths. Further, in this embodiment, an example in which grooves are formed on both main surfaces of the front and back surfaces of the vibration legs 111 and 112 has been described, but an outer groove 131 and a central groove 132 having different groove depths are formed on only one of the surfaces. It doesn't matter. Even in such a case, the object of the present invention that both vibration characteristics and impact resistance are good can be sufficiently achieved.

  Next, a method for manufacturing a resonator element having the vibration legs 111 and 112 in which a total of three grooves of two outer grooves 131 and one central groove 132 of the present invention are formed will be described.

  FIG. 3 is a view showing an example of a method for manufacturing a resonator element in which three grooves are formed on the main surface of a vibration leg used in the crystal resonator of the present invention.

  First, as shown in FIG. 3A, a mask layer 30 is formed on both surfaces of a quartz wafer 20 having a predetermined thickness in a pattern that is shaped like the outer shape of the vibration legs 111 and 112. In this embodiment, a laminated film composed of a chromium (Cr) film having a lower layer of 0.02 μm and a gold (Au) film having an upper layer of 0.12 μm is formed by sputtering, which is one of vacuum film forming methods. Used as a mask layer 30. Further, for the patterning of the mask layer 30, a photolithography method capable of accurately patterning a fine shape was used.

  Next, as shown in FIG. 3B, an outer groove pattern for forming the outer groove 131 and the central groove 132 on the mask layer 30 and a resist layer 41 patterned with the central groove pattern are formed. In this embodiment, a positive resist having a viscosity of 30 cP is used as the resist layer 41, a film having a thickness of 1.3 μm is formed by a spin coating method, and then a pattern that describes the outer shape of the vibrator is formed by a photolithography method. The outer groove pattern and the central groove pattern were patterned respectively.

  In this embodiment, the groove width a1 of the outer groove pattern is 8 μm, and the groove width b1 of the central groove pattern is 5 μm. As described above, the crystal resonator manufacturing method according to the present invention is characterized in that the groove width a1 of the outer groove pattern and the groove width b1 of the central groove pattern are different from each other.

  Thereafter, using the mask layer 30 as a mask, the crystal wafer 20 is etched to form the external shape of the crystal resonator. As a result, as shown in FIG. 3C, the vibration legs 101 and 102 in which no groove is formed are formed.

  In this example, the outer shape of the crystal unit having the vibrating legs 101 and 102 was formed by performing an etching process with buffered hydrofluoric acid at 70 ° C. for 50 minutes. Since the upper Au film used as the mask layer 30 has corrosion resistance against buffered hydrofluoric acid, it has a sufficient role as a mask, and only the portion where the mask layer 30 is not formed can be etched. On the other hand, the lower Cr film served as an adhesion layer for preventing the Au film from peeling from the crystal wafer 20, and the mask layer 30 was not peeled off during etching.

  Next, as shown in FIG. 3D, the resist layer 41 having two outer groove patterns and one central groove pattern is used as a mask, and the mask layer 31 is etched to form a resist layer. A mask layer 31 in which the outer groove pattern and the central groove pattern having the same shape as 41 are patterned is formed.

  In this embodiment, the upper gold (Au) film of the mask layer is etched with an iodine-based etchant, and the lower chromium (Cr) film is etched with a cerium nitrate-based etchant to form an outer groove having a groove width a1 = 8 μm. A central groove pattern having a pattern and a groove width b1 = 5 μm was formed.

  Thereafter, as shown in FIG. 3E, the vibrating legs 101 and 102 are etched with a chemical solution such as hydrofluoric acid using the mask layer 31 on which the outer groove pattern and the central groove pattern are patterned as a mask. And a central groove 132 is formed. Then, the vibration legs 111 and 112 are formed in which the central groove 132 having a shallow groove depth and two outer grooves 131 arranged on both sides thereof and having a deep groove depth are carved on the main surface.

  In the present embodiment, the etching process is performed for 70 minutes with 70 ° C. buffered hydrofluoric acid, whereby the outer groove 131 having a groove depth d1 of 58 μm and the central groove 132 having a groove depth d2 of 53 μm are formed on the vibrating legs 111, 112. Could be formed on the main surface.

  The crystal resonator manufacturing method of the present invention utilizes the phenomenon that a groove pattern with a wider groove width has a higher crystal etching rate in the depth direction than a groove pattern with a narrow groove width. Due to this phenomenon, the outer groove 131 having a wide groove width a1 is formed deeper than the central groove 132 having a narrow groove width b1.

  As described above, according to the method for manufacturing a crystal resonator of the present invention, grooves having different depths can be simultaneously processed in one process, and thus productivity is good.

  Finally, as shown in FIG. 3 (f), the resist layer 41 and the mask layer 31 are peeled off, and the vibration legs 111 and 112 having one central groove 132 and two outer grooves 131 formed on the main surface are formed. The vibrating piece 80 is completed.

  Next, another method for manufacturing the crystal resonator according to the present invention with higher productivity will be described. FIG. 4 is a diagram showing another example of a method for manufacturing a resonator element in which three grooves are formed on the main surface of a vibration leg used in the crystal resonator of the present invention.

  First, as shown in FIG. 4A, a pattern that describes the outer shape of the vibrating legs 111 and 112 and a single groove for forming a central groove 132 are formed on both surfaces of a quartz wafer 20 having a predetermined thickness. The mask layer 31 in which the central groove pattern and the outer groove pattern for forming the outer groove 131 are patterned is formed. In this embodiment, a laminated film composed of a chromium (Cr) film having a lower layer of 0.02 μm and a gold (Au) film having an upper layer of 0.12 μm is formed by sputtering, which is one of vacuum film forming methods. And used as the mask layer 31. Also, the outer shape of the vibration leg, the outer groove pattern with a groove width a2 of 4 μm, and the central groove pattern with a groove width b2 of 2 μm were patterned by using a photolithography method.

  Next, as shown in FIG. 4B, the crystal wafer 20 is etched with a chemical solution such as hydrofluoric acid using the mask layer 31 in which the outer groove pattern and the central groove pattern are patterned as a mask. Then, the vibration legs 111 and 112 are formed in which the central groove 132 having a shallow groove depth and two outer grooves 131 arranged on both sides thereof and having a deep groove depth are carved on the main surface.

  In this embodiment, by performing an etching process with buffered hydrofluoric acid at 70 ° C. for 120 minutes, the outer groove 131 having a groove depth d1 of 58 μm and the central groove 132 having a groove depth d2 of 53 μm are formed into the vibrating legs 111 and 112, respectively. Could be formed on the main surface.

  Finally, as shown in FIG. 4C, the resist layer 41 and the mask layer 31 are peeled off, and the vibration legs 111 and 112 having one central groove 132 and two outer grooves 131 on the main surface are formed. The vibrating piece 80 is completed.

  The present embodiment is characterized in that the groove width a2 of the outer groove pattern patterned on the mask layer 31 and the groove width b2 of the central groove pattern are patterned very narrowly. When the groove width of the groove pattern is narrow, the crystal etching rate of the groove is extremely slow compared to the crystal etching rate around the crystal resonator outer shape. As a result, even if the etching process is performed for such a long time that the periphery of the outer shape of the crystal resonator penetrates, the narrow groove portion does not penetrate.

  In this way, if the method for manufacturing a crystal resonator shown in this embodiment is used, the number of work steps is reduced, and the productivity is improved.

  Next, an example in which the present invention is applied to a crystal resonator having four grooves on the main surface will be described. FIG. 5 is a cross-sectional view of a vibrating leg of a crystal resonator having four grooves according to the present invention. As shown in FIG. 5, the vibration legs 115 and 116 have two outer grooves 131 and two central grooves 132 sandwiched between the two outer grooves, aligned in the width direction of the vibration legs 115 and 116. There are four on the surface and eight on each side. The groove depth of the outer groove 131 is d1, and the groove depth of the central groove 132 is shallower than d3 (<d1). In this embodiment, the outer groove 131 having a groove depth d1 of 58 μm and the central groove having a groove depth d3 of 48 μm are formed on the vibrating legs 115 and 116 having a thickness t of 128 μm.

  A quartz crystal unit having four grooves formed on the main surface of this example was manufactured in the same manner as the manufacturing method shown in FIG.

  Specifically, first, a mask layer 30 having a laminated structure of an Au film and a Cr film is formed on the front and back surfaces of the crystal wafer 20 with a resonator element outer pattern, and then a plurality of groove patterns with different widths are formed on the mask layer 30. A patterned resist layer 41 was formed. In this embodiment, the groove width a1 of the outer groove pattern corresponding to the two outer grooves 131 is patterned with 8 μm, and the groove width b1 of the center groove pattern corresponding to the two central grooves 132 is patterned with 4 μm.

  Next, the quartz wafer was etched using the mask layer 30 as a mask to form the outer shape of the resonator element. In this embodiment, the outer shape of the crystal unit having the vibrating legs 101 and 102 is formed by etching with buffered hydrofluoric acid at 70 ° C. for 50 minutes.

  Next, the mask layer 30 was etched using the resist layer 41 as a mask to form a mask layer 31 in which the outer groove pattern and the central groove pattern having the same shape as the resist layer 41 were patterned on the mask layer.

  Thereafter, the mask layer 31 on which the outer groove pattern and the central groove pattern are formed is used as a mask to etch the main surfaces of the vibrating legs 101 and 102 to form the outer grooves 131 and the central grooves 132 having different groove depths. Two were formed. In this embodiment, etching is performed with 70 ° C. buffered hydrofluoric acid for 70 minutes, whereby two outer grooves 131 having a groove depth d1 of 58 μm and two central grooves 132 having a groove depth d2 of 48 μm. Can be formed on the main surfaces of the vibrating legs 115 and 116.

  Even in the case of a crystal resonator in which four grooves are formed on the main surfaces of the vibrating legs 115 and 116 as in this embodiment, the two central grooves 132 sandwiched between the two outer grooves 131 are used. By reducing the groove depth, it is possible to provide a crystal resonator having a low CI value, good vibration characteristics, excellent impact resistance, and high reliability.

10, 11 Quartz crystal resonator 20 Crystal wafer 30, 31, 32 Mask layer 41, 42 Resist layer 51, 52 Electrode 80, 81 Vibrating piece 101, 102, 103, 104 Vibrating leg 111, 112, 113, 114, 115, 116 Vibration leg 120 Base 130 Groove 131 Outer groove 132 Central groove

Claims (4)

  A crystal resonator in which an electrode is formed on a vibrating piece having a base and a vibrating leg protruding from the base, wherein a plurality of grooves arranged in the width direction of the vibrating leg are formed on the main surface of the vibrating leg. The plurality of grooves are composed of two outer grooves and a central groove between the outer grooves, and the central groove is shallower than the outer groove. .   A method of manufacturing a crystal resonator in which an electrode is formed on a vibrating piece having a base, a vibrating leg protruding from the base, and a plurality of grooves formed on a main surface of the vibrating leg, the crystal wafer Forming a mask layer having corrosion resistance patterned with a vibrating piece outer shape pattern having a vibrating leg outer shape pattern and a base outer shape pattern on the front and back surfaces of the substrate, and etching the crystal wafer to form an outer shape of the vibrating piece And forming a plurality of groove patterns with different widths in the mask layer after forming the outer shape of the vibrating piece, and forming grooves having different depths on the main surface of the vibrating leg. A method of manufacturing a crystal resonator, comprising:   A method of manufacturing a crystal resonator in which an electrode is formed on a vibrating piece having a base, a vibrating leg protruding from the base, and a plurality of grooves formed on a main surface of the vibrating leg, the crystal wafer Forming a mask layer having corrosion resistance in which a vibrating piece outer shape pattern having a vibrating leg outer shape pattern and a base outer shape pattern and a plurality of groove patterns having different widths are patterned on the front and back surfaces of the substrate, and using the mask layer as a mask And a step of etching the quartz wafer to simultaneously form an outer shape of the vibrating piece and grooves having different depths on the main surface of the vibrating leg. .   The groove pattern formed in the mask layer is a three groove pattern of a central groove pattern and an outer groove pattern disposed on both sides of the central groove pattern, and only the central groove pattern is more than the outer groove pattern. 4. The method for manufacturing a crystal resonator according to claim 2, wherein the groove width is narrow.

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