JP5890271B2 - Tuning fork-type bending crystal resonator element and manufacturing method thereof - Google Patents

Description

  The present invention relates to a tuning-fork type bending crystal resonator element used in electronic equipment and the like and a method for manufacturing the same.

  In an electronic device such as a computer, a mobile phone, or a small information device, a crystal resonator or a crystal oscillator is mounted as one of electronic components. This crystal resonator or crystal oscillator is used as a reference signal source or a clock signal source. A tuning fork-type bending quartz crystal vibration element (hereinafter abbreviated as “vibration element”) is mounted inside the crystal resonator or the crystal oscillator. Hereinafter, the vibration element described in Patent Document 1 will be described.

  As shown in FIGS. 6 and 7, the related art vibrating element 100 ′ is mainly composed of a quartz crystal vibrating piece 10 ′, excitation electrodes 21 a and 21 b, connection electrodes 22 a and 22 b, and wiring patterns 23 a and 23 b. The X axis, Y ′ axis, and Z ′ axis in the figure are crystal axes of the quartz crystal substrate.

  The quartz crystal vibrating piece 10 ′ is composed of a base portion 11, a vibrating arm portion 12, and a protruding portion 13 ′. The vibrating arm portion 12 includes a first vibrating arm portion 12a and a second vibrating arm portion 12b. The quartz crystal vibrating piece 10 ′ is manufactured by a photolithography technique, a chemical etching technique, and a film forming technique. The vibrating arm portion 12 is provided with groove portions 161 to 164.

  A slit 14 is provided on the distal end side of the protruding portion 13 ′ along the extending direction. The slit 14 penetrates in the thickness direction of the protrusion 13 '. The width 13w 'of the protrusion 13' is the same size from the tip to the base end.

  The slit 14 provided in the protrusion 13 ′ is used to form the excitation electrode on the side surface of the first vibrating arm portion 12 a when the excitation electrodes 21 a and 21 b are formed on the side surface of the vibrating arm portion 12 by the sputtering technique and the photolithography technique. 21b and the excitation electrode 21a on the side surface of the second vibrating arm portion 12b are prevented from being connected.

  Next, in order to explain the role of the slit 14, a method for manufacturing the vibration element 100 ′ will be described.

  First, a corrosion resistant film (not shown) is formed on the front and back of a quartz wafer (not shown) by sputtering. Subsequently, a photosensitive resist (positive type) is formed on the corrosion resistant film on both sides of the quartz wafer, and after drying the photosensitive resist, the corrosion resistant film is patterned so that a tuning fork-shaped corrosion resistant film remains on both sides of the front and back sides ( Exposure, development, and drying) and removing the anticorrosion film other than the tuning fork shape by etching.

  Subsequently, a photosensitive resist (positive type) is patterned on the front and back corrosion resistant films in order to determine the shape of the electrodes. The crystal portion that becomes the slit 14 is directly covered with a photosensitive resist without using a corrosion-resistant film.

  Subsequently, the exposed crystal portion is removed by wet etching. At this time, the shape of the slit 14 and the shape of the quartz crystal vibrating piece 10 'are formed simultaneously. That is, the base 11, the vibrating arm 12, and the protrusion 13 'are formed with the photosensitive resist remaining. Note that the photosensitive resist covering the protrusion 13 ′ is left in a state of straddling the slit 14.

  Subsequently, the corrosion-resistant film exposed on the front and back surfaces of the quartz crystal vibrating piece 10 'is removed by etching. Thereby, a crystal surface is obtained.

  Subsequently, an electrode film is formed on the entire surface of the quartz crystal vibrating piece 10 ′ with the photosensitive resist left by a sputtering technique. At this time, an electrode film is formed on the side surface of the protrusion 13 ′ across the slit 14 by the photosensitive resist that covers the protrusion 13 ′ across the slit 14.

  Subsequently, the photosensitive resist formed on the front and back surfaces of the quartz crystal vibrating piece 10 ′ and the electrode film formed thereon are peeled off. This is realized by immersing these in a solution for dissolving the photosensitive resist. At this time, since the photosensitive resist straddling the slit 14 is also removed, the excitation electrode 21b and the second vibrating arm portion on the side surface of the first vibrating arm portion 12a connected via the electrode film on the photosensitive resist. The excitation electrode 21a on the side surface of 12b is cut off.

  Finally, the corrosion-resistant film remaining under the photosensitive resist is removed by etching.

  In this way, since the electrodes are formed on the crystal vibrating piece 10 ′, the excitation electrode 21b on the side surface of the first vibrating arm portion 12a and the excitation electrode 21a on the side surface of the second vibrating arm portion 12b can be used even when the sputtering technique is used. Can be cut by the slit 14.

JP 2011-151567 A

  However, the related art vibrating element 100 ′ has the following problems.

  The width 13w 'of the protrusion 13' is extremely narrow, and the narrowness continues from the distal end to the proximal end. For this reason, when the action of wet etching proceeds excessively, the shape of the protruding portion 13 ′ may be greatly impaired, such as a part of the protruding portion 13 ′ being cut off. In addition, since the width of the resist pattern formed on the protrusion 13 ′ is extremely narrow, the resist pattern may not sufficiently straddle the slit 14 depending on the positional deviation of the resist pattern (particularly in the ± X axis direction). It was. Further, since the contact area between the protrusion 13 'and the resist pattern formed thereon becomes narrow, the resist pattern may be peeled off by the pressure of the wet etching solution. Further, due to the fine shape, the protrusion 13 ′ may be damaged during the formation of the electrode film after the formation of the protrusion 13 ′, electrical inspection, package mounting, transfer, and the like. As described above, in the vibration element 100 ′, the shape of the protrusion 13 ′ has been a factor in reducing the manufacturing yield.

  Quartz is composed of a trigonal single crystal composed of silicon and oxygen. The growth axis (optical axis) is the Z axis, and the axis connecting the ridge line perpendicular to this is the X axis (electric axis). An axis perpendicular to the axis is expressed as a Y axis (machine axis). The etching rates during the wet etching of these three axes are in the order of Z> X> Y. Therefore, as shown in FIGS. 6 and 7, residues 15a 'and 15b' are generated in the crystal after the wet etching at the protrusion 13 '. However, the residue 15a 'generated on the first vibrating arm portion 12a side and the residue 15b' generated on the second vibrating arm portion 12b side have different shapes and sizes. As a result, the vibration frequency is unbalanced between the right side and the left side of the tuning fork, so that the vibration propagates to the base 11 side, resulting in an increase in CI (Crystal Impedance) value.

  Accordingly, a main object of the present invention is to provide a vibration element and a method of manufacturing the same that can achieve a reduction in CI value while improving the manufacturing yield.

The vibration element according to the present invention is
A base, two vibrating arms extending in the same direction from the base, a protrusion extending in the one direction from the base between the two vibrating arms, and the protrusion A crystal vibrating piece comprising a slit provided in the section,
The protrusion is divided into a tip farthest from the base, a base end closest to the base, and a transition region between the base and the tip,
The slit is provided from the base side to the tip along the one direction,
When the length in a direction perpendicular to the one direction and intersecting the two vibrating arm portions in the transition region is defined as a width, the width increases as the distance from the distal end increases to the proximal end.
It is characterized by that.

A method for manufacturing a resonator element according to the present invention is a method for manufacturing a crystal resonator element according to the present invention,
A first step of forming and patterning a corrosion-resistant film on a quartz substrate;
A second step of forming a resist pattern on the corrosion-resistant film and on the exposed portion of the quartz crystal substrate serving as the slit;
A third step of forming the quartz crystal vibrating piece by removing the exposed portion of the quartz substrate not covered with the corrosion-resistant film by wet etching;
A fourth step of removing the corrosion-resistant film not covered with the resist pattern;
A fifth step of forming an electrode film on the exposed portion of the crystal vibrating piece excluding the inside of the slit and on the resist pattern;
A sixth step of removing the electrode film formed on the resist pattern together with the resist pattern;
A seventh step of removing the corrosion-resistant film exposed by removing the resist pattern;
It is characterized by including.

  According to the present invention, since the width of the protrusion between the two vibrating arms increases as the distance from the distal end to the proximal end increases, various manufacturing problems can be solved, so that the manufacturing yield can be improved. Since the residue generated at the base of the vibrating arm portion of the book can be made small and equal, the CI value can be reduced.

FIG. 3 is a perspective view illustrating a vibration element according to the first embodiment. FIG. 3 is a plan view showing the resonator element according to the first embodiment. It is sectional drawing which shows the manufacturing process of the III-III line longitudinal cross section in FIG. 2, and a process progresses in order of FIG. 3 [1], FIG. 3 [2], FIG. 3 [3], and FIG. It is sectional drawing which shows the manufacturing process of the III-III line longitudinal cross section in FIG. 2, and a process progresses in order of FIG. 4 [5], FIG. 4 [6], and FIG. 4 [7]. 6 is a plan view illustrating a part of the vibration element according to Embodiment 2. FIG. It is a perspective view which shows the vibration element of related technology. It is a top view which shows the vibration element of related technology.

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments for carrying out the present invention (hereinafter referred to as “embodiments”) will be described with reference to the accompanying drawings. In addition, since the shape drawn in drawing is drawn so that those skilled in the art can understand easily, it does not necessarily correspond with an actual dimension and ratio.

  FIG. 1 is a perspective view illustrating a vibration element according to the first embodiment. FIG. 2 is a plan view showing the resonator element according to the first embodiment. Hereinafter, description will be given based on these drawings.

  The resonator element 100 according to the first embodiment includes a crystal resonator element 10. The quartz crystal resonator element 10 includes a base portion 11, two vibrating arm portions 12 extending from the base portion 11 in the same direction (Y′-axis direction), and one base portion 11 between the two vibrating arm portions 12. It consists of a protrusion 13 extending in the direction (Y′-axis direction) and a slit 14 provided in the protrusion 13.

  The protrusion 13 is divided into a distal end 131 farthest from the base 11, a proximal end 133 closest to the base 11, and a transition region 132 between the proximal end 133 and the distal end 131. The slit 14 is provided from the base 11 side to the tip 131 along one direction (Y′-axis direction). In the transition region 132, when the length in the direction perpendicular to one direction (Y′-axis direction) and intersecting the two vibrating arm portions 12 is defined as the width 13w, the width 13w becomes wider as the distance from the distal end 131 toward the proximal end 133 increases. .

  In this case, the proximal end 133 may reach the roots of the two vibrating arm portions 12 with respect to the base portion 11 as illustrated. Further, the shape of the transition region 132 may be triangular as shown in the figure.

  Next, the configuration of the vibration element 100 will be described in more detail.

  As shown in FIGS. 1 and 2, the resonator element 100 includes a quartz crystal vibrating piece 10, excitation electrodes 21 a and 21 b, connection electrodes 22 a and 22 b, and wiring patterns 23 a and 23 b provided on the quartz crystal vibrating piece 10. It is configured. If necessary, a frequency adjusting metal film may be provided on the crystal vibrating piece 10.

  The quartz crystal vibrating piece 10 has a tuning fork shape, and extends from the base 11 between the base 11, the pair of two vibrating arms 12 extending from the base 11, and the two vibrating arms 12. It is roughly comprised by the provided projection part 13. FIG. The vibrating arm portion 12 is provided with excitation electrodes 21a and 21b having the same polarity on opposite surfaces across the quartz.

  The base 11 is a flat plate having a substantially rectangular shape in plan view. The vibrating arm portion 12 includes a first vibrating arm portion 12a and a second vibrating arm portion 12b. The first vibrating arm portion 12a and the second vibrating arm portion 12b extend from one side of the base portion 11 in the same direction (Y′-axis direction). The quartz crystal vibrating piece 10 has a tuning fork shape in which a base portion 11 and a vibrating arm portion 12 are integrated, and is manufactured by a photolithography technique, a chemical etching technique, and a film forming technique.

  In addition, you may provide the groove parts 161-164 in the length direction of the 1st vibration arm part 12a and the 2nd vibration arm part 12b, respectively. The groove portions 161 to 164 are, for example, two on the front and back surfaces of the first vibrating arm portion 12a and two on the front and back surfaces of the second vibrating arm portion 12b. A predetermined length is provided parallel to the length direction of the vibrating arm portion 12 toward the tip. In addition, you may provide the groove parts 161-164 only in either one side of the front and back. In the first embodiment, two grooves 161 to 164 are provided on the front and back surfaces of the first vibrating arm portion 12a and two grooves on the front and back surfaces of the second vibrating arm portion 12b. There is no limitation, and for example, one may be provided on the front and back surfaces of the first vibrating arm portion 12a and one on the front and back surfaces of the second vibrating arm portion 12b.

  The excitation electrode 21a is provided on one and the other main surfaces of the first vibrating arm portion 12a, and on the inner and outer side surfaces of the second vibrating arm portion 12b. The excitation electrode 21b is provided on one and the other main surfaces of the second vibrating arm portion 12b, and on the inner and outer side surfaces of the first vibrating arm portion 12a.

  The base 11 is provided with connection electrodes 22a and 22b. Further, the base portion 11 and the vibrating arm portion 12 are provided with wiring patterns 23a and 23b for electrically connecting predetermined electrodes. The excitation electrode 21a, the connection electrode 22a, and the wiring pattern 23a are electrically connected to each other. The excitation electrode 21b, the connection electrode 22b, and the wiring pattern 23b are also electrically connected to each other.

  The excitation electrodes 21a and 21b, the connection electrodes 22a and 22b, and the wiring patterns 23a and 23b are formed by a photolithography technique, and have a laminated structure in which, for example, a Pd or Au layer is provided on a Ti layer.

  When the tuning fork type crystal vibrating piece 10 is vibrated, an alternating voltage is applied to the connection electrodes 22a and 22b. When an electrical state after application is captured instantaneously, the excitation electrodes 21a provided on both main surfaces of the first vibrating arm portion 12a have a positive potential, and excitation provided on both side surfaces of the first vibrating arm portion 12a. The electrode 21b has a negative potential, and an electric field is generated from positive to negative. At this time, the excitation electrodes 21b provided on both main surfaces of the second vibrating arm portion 12b have a negative potential, the excitation electrodes 21a provided on both side surfaces of the second vibrating arm portion 12b have a positive potential, and the first vibrating arm. The polarity is opposite to that generated in the portion 12a, and an electric field is generated from plus to minus. The electric field generated by the alternating voltage causes an expansion / contraction phenomenon in the first vibrating arm portion 12a and the second vibrating arm portion 12b, and a bending vibration mode having a resonance frequency set in the vibrating arm portion 12 is obtained.

  The protrusion 13 is in the middle of the pair of vibrating arms 12 and extends from the base 11 along the vibrating arms 12. Further, the protruding portion 13 is provided so that the width 13 w becomes wider as it advances from the distal end 131 to the proximal end 133. A slit 14 is provided at the tip 131 of the protrusion 13 along the extending direction. The slit 14 penetrates in the thickness direction of the protrusion 13.

  The slit 14 provided in the protrusion 13 is formed on the side surface of the vibrating arm portion 12 when the excitation electrodes 21a and 21b are formed by the sputtering technique and the photolithography technique. And the excitation electrode 21a on the side surface of the second vibrating arm portion 12b.

  3 and 4 are cross-sectional views at each step corresponding to the vertical cross section taken along line III-III in FIG. Hereinafter, a method for manufacturing the vibration element 100 will be described with reference to FIGS.

  The manufacturing method of Embodiment 1 includes the following first to seventh steps.

  In the first step shown in FIG. 3 [1], a corrosion-resistant film 32 is formed on the quartz substrate 31 and patterned. For example, a corrosion-resistant film 32 such as Cr or Cr + Au is formed on the front and back of the quartz substrate 31 by sputtering. Then, a photosensitive resist (positive type) is formed on the corrosion-resistant film 32, and after the photosensitive resist is dried, patterning is performed so that the tuning-fork-shaped corrosion-resistant film 32 remains on the front and back of the quartz substrate 31 (exposure, development, drying). Then, the anticorrosion film 32 other than the tuning fork shape is removed by etching.

  In the second step shown in FIG. 3 [2], a resist pattern 33 is formed on the corrosion-resistant film 32 and on the exposed portion 311 of the quartz crystal substrate 31 to be the slit 14. For example, a photosensitive resist (positive type) is patterned in order to determine the shape of the electrodes on the corrosion-resistant films 32 on the front and back surfaces of the quartz substrate 31.

  In the third step shown in FIG. 3 [3], the quartz vibrating piece 10 is formed by removing the exposed portion of the quartz substrate 31 that is not covered with the corrosion-resistant film 32 by wet etching. At this time, the shape of the slit 14 and the shape of the crystal vibrating piece 10 are formed simultaneously. At this time, the slit 14 is formed by under-etching from below the resist pattern 33. Therefore, the resist pattern 33 is left at least on the protrusion 13 in a state of straddling the slit 14. That is, the base 11, the vibrating arm 12, and the protrusion 13 are formed with the resist pattern 33 left.

  In addition, when providing the groove parts 161-164 in the vibration arm part 12, you may form the groove parts 161-164 simultaneously with the shape of the crystal vibrating piece 10 at this 3rd process. However, when the groove portions 161 to 164 are provided on the front and back surfaces of the vibrating arm portion 12, it is desirable to form an etching suppression pattern in the groove portions 161 to 164 in order to avoid penetration of the groove portions 161 to 164.

  In the fourth step shown in FIG. 3 [4], the corrosion resistant film 32 not covered with the resist pattern 33 is removed. That is, the crystal surface is obtained by removing the corrosion-resistant film 32 exposed on the front and back surfaces of the crystal vibrating piece 10 by etching.

  In the fifth step shown in FIG. 4 [5], the electrode film 34 is formed on the exposed portion of the crystal vibrating piece 10 and the resist pattern 33 except for the inside of the slit 14. For example, the electrode film 34 is formed on the entire surface of the quartz crystal vibrating piece 10 by a sputtering technique. At this time, the electrode film 34 is formed on the side surface of the protrusion 13 across the slit 14 by the resist pattern 33 covering the protrusion 13 across the slit 14.

  In the sixth step shown in FIG. 4 [6], the electrode film 34 formed on the resist pattern 33 is removed together with the resist pattern 33. That is, the resist pattern 33 formed on the front and back surfaces of the quartz crystal vibrating piece 10 and the electrode film 34 formed thereon are peeled off. This can be easily removed by immersing them in a solution (for example, acetone) for dissolving the photosensitive resist. However, the corrosion resistant film 32 under the resist pattern 33 remains. Since the resist pattern 33 straddling the slit 14 is also removed, the excitation electrode 21b on the side surface of the first vibrating arm portion 12a and the excitation electrode 21a on the side surface of the second vibrating arm portion 12b are cut by the slit 14. . This electrode film forming method in the sixth step is generally called a lift-off method.

  In the seventh step shown in FIG. 4 [7], the corrosion-resistant film 32 exposed by removing the resist pattern 33 is removed. That is, the corrosion-resistant film 32 remaining until the end is removed by etching.

  Since the excitation electrodes 21a and 21b are thus formed on the quartz crystal vibrating piece 10, even if sputtering technology is used, the excitation electrodes 21b on the side surfaces of the first vibrating arm portion 12a and the side surfaces of the second vibrating arm portion 12b are excited. The electrode 21 a can be cut by the slit 14.

  Next, the action and effect when the vibration element 100 of the first embodiment is compared with related technology will be described.

  As shown in FIGS. 1 and 2, the width 13 w of the protrusion 13 increases as the distance from the distal end 131 toward the proximal end 133 increases. For this reason, the influence on the shape of the protrusion 13 such that the protrusion 13 is likely to be partially applied due to excessive wet etching action can be reduced by increasing the width 13 w of the protrusion 13. Further, since the width of the resist pattern 33 formed on the protrusion 13 is also widened, the resist pattern 33 can sufficiently straddle the slit 14 even if the position of the resist pattern 33 is slightly shifted (FIG. 3). [Refer to [2]). Further, since the contact area between the protrusion 13 and the resist pattern 33 formed thereon is increased, peeling of the resist pattern 33 due to the pressure of the wet etching solution can be suppressed (see FIG. 3 [3]). Furthermore, because of the wide shape, it is possible to prevent the protrusion 13 from being damaged during electrode film formation, electrical inspection, package mounting, transfer, and the like after the protrusion 13 is formed. Thus, according to the vibration element 100, since the shape of the protrusion 13 is wide as described above, the manufacturing yield can be improved.

  Further, since the width 13w of the protrusion 13 is narrow at the tip 131 and the base end 133 is wide, the electrode material is likely to enter the root inside the vibrating arm 12 during film formation such as sputtering or vapor deposition. That is, the protrusion 13 has a structure that does not obstruct the formation of the electrode film 34 on the inner side surface of the vibrating arm 12 (see FIG. 4 [5]). Therefore, since the electrode film 34 can be sufficiently formed up to the inner base of the vibrating arm portion 12, it is possible to prevent a reduction in electric field efficiency of the vibrating element 100. In particular, when the shape of the transition region 132 is triangular, the transition region 132 does not bulge outward, that is, it is difficult to shield the electrode material flying during film formation. The material can be guided to the inner root of the vibrating arm portion 12.

  Further, the width 13w of the protrusion 13 increases as the distance from the distal end 131 to the proximal end 133 increases, so that a region where crystal residue is generated after wet etching can be reduced. Therefore, as shown in FIGS. 1 and 2, the residue 15a generated on the first vibrating arm portion 12a side and the residue 15b generated on the second vibrating arm portion 12b side can be formed small and equal. As a result, the vibration frequency on the right side and the left side of the tuning fork can be made equal, and the CI value can be reduced. In particular, when the base end 133 reaches the base of the base portion 11 of the vibrating arm portion 12, the region where the crystal residue is generated can be narrowed without affecting the vibrating arm portion 12. Become prominent.

  As described above, according to the vibration element 100, the width 13w of the protrusion 13 becomes wider as it advances from the distal end 131 to the proximal end 133, so that various manufacturing problems can be solved, so that the manufacturing yield can be improved. Since the residues 15a and 15b generated at the bases of the two vibrating arm portions 12 can be made small and equal, the CI value can be reduced.

  FIG. 5 is a plan view illustrating a part of the resonator element according to the second embodiment. Hereinafter, description will be given based on this drawing.

  In the resonator element according to the second embodiment, the shape of the protrusion 43 is different from that of the first embodiment. That is, the protrusion 43 in the second embodiment is divided into a distal end 431 farthest from the base 11, a proximal end 433 closest to the base 11, and a transition region 432 between the proximal end 433 and the distal end 431. The slit 14 is provided from the base 11 side to the tip 431 along one direction (Y′-axis direction). In the transition region 432, when the length in the direction perpendicular to one direction (Y′-axis direction) and intersecting the two vibrating arm portions 12 is the width 43 w, the width 43 w becomes wider as the distance from the distal end 431 toward the proximal end 433 increases. . The shape of the transition region 432 is a semicircular shape that protrudes outward.

  According to the resonator element of the second embodiment, the shape of the transition region 432 is a semicircular shape that protrudes outward, so that the area of the protrusion 43 and the contact area between the protrusion 43 and the resist pattern 33 are wider. As a result, the above-described effects become more prominent. Other configurations, operations, and effects of the second embodiment are the same as those of the first embodiment.

  Although the present invention has been described with reference to the above embodiments, the present invention is not limited to the above embodiments. Various changes that can be understood by those skilled in the art can be made to the configuration and details of the present invention. Further, the present invention includes a combination of some or all of the configurations of the above-described embodiments as appropriate.

DESCRIPTION OF SYMBOLS 100 Vibrating element 10 Crystal vibrating piece 11 Base 12 Vibrating arm part 12a 1st vibrating arm part 12b 2nd vibrating arm part 13 Protrusion part 131 Tip 132 Transition area 133 Base end 13w Width 14 Slit 15a, 15b Residues 161, 162, 163 164 Groove portion 21a, 21b Excitation electrode 22a, 22b Connection electrode 23a, 23b Wiring pattern 31 Quartz substrate 311 Exposed portion 32 Corrosion resistant film 33 Resist pattern 34 Electrode film

43 Protruding part 431 Tip 432 Transition region 433 Base 43w Width

100 'vibrating element 10' crystal vibrating piece 13 'protrusion 13w' width 15a ', 15b' residue

Claims (5)

A base, two vibrating arms extending in the same direction from the base, a protrusion extending in the one direction from the base between the two vibrating arms, and the protrusion A crystal vibrating piece comprising a slit provided in the section,
The protrusion is divided into a tip farthest from the base, a base end closest to the base, and a transition region between the base and the tip,
The slit is provided from the base side to the tip along the one direction,
When the length in a direction perpendicular to the one direction and intersecting the two vibrating arm portions in the transition region is defined as a width, the width increases as the distance from the distal end increases to the proximal end.
A tuning fork-type bending crystal resonator element characterized by that. The proximal end reaches the root of the two vibrating arms with respect to the base,
The tuning-fork type bending crystal resonator element according to claim 1. The transition region has a triangular shape;
The tuning-fork type bending crystal resonator element according to claim 1 or 2. The shape of the transition region is a semicircular shape that is convex outward,
The tuning fork-type bending quartz crystal vibrating element according to any one of claims 1 to 3. A method for manufacturing a tuning-fork type bending crystal resonator element according to any one of claims 1 to 4,
A first step of forming and patterning a corrosion-resistant film on a quartz substrate;
A second step of forming a resist pattern on the corrosion-resistant film and on the exposed portion of the quartz crystal substrate serving as the slit;
A third step of forming the quartz crystal vibrating piece by removing the exposed portion of the quartz substrate not covered with the corrosion-resistant film by wet etching;
A fourth step of removing the corrosion-resistant film not covered with the resist pattern;
A fifth step of forming an electrode film on the exposed portion of the crystal vibrating piece excluding the inside of the slit and on the resist pattern;
A sixth step of removing the electrode film formed on the resist pattern together with the resist pattern;
A seventh step of removing the corrosion-resistant film exposed by removing the resist pattern;
A method for manufacturing a tuning-fork-type bending crystal resonator element, comprising:

Images