JP2013138512A - Method of manufacturing vibration piece - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a piezoelectric vibration piece whose outer shape size can be reduced.SOLUTION: A piezoelectric vibration piece comprises a frame part 2 and a vibration part 3. The frame part 2 includes in its outer periphery a sidewall portion 2c connecting one principal surface 2a and another principal surface 2b. The sidewall portion 2c includes a first slope 2d and a second slope 2e. The first slope 2d is tilted from the one principal surface 2a to the other principal surface 2b and in the first slope 2d, an end 2f at the side of the other principal surface 2b is formed outside of a contour 2i of the one principal surface 2a in a plane view. The second slope 2e is tilted from the other principal surface 2b to the one principal surface 2a and in the second slope 2e, an end 2g at the side of the one principal surface 2a is formed outside of a contour 2j of the other principal surface 2b in a plane view. In at least a part of the sidewall portion 2c, the end 2f of the first slope 2d at the side of the other principal surface 2b and the end 2g of the second slope 2e at the side of the one principal surface 2a are abutted. A distance L1 from the one principal surface 2a to the end 2f of the first slope 2d at the side of the other principal surface 2b in a first direction approximately orthogonal to the one principal surface 2a is shorter than a distance L2 from the one principal surface 2a to a vibration plane 3a of the vibration part 3 at the side of the one principal surface 2a.

Description

  The present invention relates to a piezoelectric vibrating piece, a piezoelectric device including the piezoelectric vibrating piece, and a method for manufacturing the piezoelectric vibrating piece.

In recent years, piezoelectric devices used in various electronic devices such as information devices and mobile communication devices have been required to be further reduced in size and performance as electronic devices become smaller and more functional.
In order to meet this requirement, each component constituting the piezoelectric device is reduced in size and performance, and the piezoelectric vibrating piece is being reduced in size and increased in frequency.
As for this small and high-frequency piezoelectric vibrating piece, there is known a shape in which a concave portion is provided on one main surface of a piezoelectric vibrating piece (piezoelectric piece) and the bottom portion of the concave portion is a vibrating portion ( For example, see Patent Document 1). In addition, this piezoelectric vibrating piece is called an inverted mesa type, and a recess and an outer shape are formed by etching.

JP 2002-271167 A

FIG. 7 is a schematic view showing an example of a conventional inverted mesa type piezoelectric vibrating piece. FIG. 7A is a plan view, and FIG. 7B is a cross-sectional view taken along the line CC of FIG. 7A. FIG. 8 is a schematic cross-sectional view showing a conventional method for manufacturing a piezoelectric vibrating piece.
As shown in FIG. 7, a plurality of piezoelectric vibrating reeds 301 are formed on the piezoelectric substrate 105 in a grid shape. Further, in the piezoelectric vibrating piece 301, the cross-sectional shape of the thick portion 102 of the concave portion is formed in a substantially trapezoidal shape. Therefore, in the piezoelectric vibrating piece 301, the width W2 of the thick portion 102 on one main surface 102a is narrower than the width W1 of the thick portion 102 in the vicinity of the vibration surface 103a of the vibration portion 103.

As shown in FIGS. 8 (a) and 8 (b), as a procedure of the conventional method of manufacturing a piezoelectric vibrating piece, when the vibrating portion 103 is formed on the piezoelectric substrate 105, the thick portion 102 is simultaneously formed. After forming the outer shape on the one main surface 102a side, as shown in FIGS. 8C and 8D, the outer shape on the other main surface 102b side of the thick portion 102 is formed. To do.
That is, the outer portion of the thick portion 102 on the one main surface 102a side is continuously etched together until the vibrating portion 103 reaches a desired thickness. In general, the thickness of the vibrating portion 103 is much thinner than the thickness of the thick portion 102 as the frequency increases.
As a result, the outer shape of the thick portion 102 on the one main surface 102a side is formed by being etched beyond the half of the thickness of the thick portion 102 to the vicinity of the other main surface 102b. For this reason, in the piezoelectric vibrating piece 301, the cross-sectional shape of the thick portion 102 is formed in a substantially trapezoidal shape. Reference numerals 106 and 107 in FIG. 8 indicate resists.

As a result, the piezoelectric vibrating reed 301 has a contact area of one main surface 102a of the thick portion 102 when the one main surface 102a side of the thick portion 102 is fixed to a support member of a package (not shown) with an adhesive or the like. There is a risk that the required fixing strength cannot be secured.
In order to avoid this problem while maintaining the substantially trapezoidal shape of the thick portion 102, it is necessary to increase the width W2 of the thick portion 102 by increasing the width W1 of the thick portion 102 of the piezoelectric vibrating piece 301. There is.
For this reason, when the size of the vibrating portion 103 cannot be reduced due to performance limitations, the piezoelectric vibrating piece 301 must be increased in outer size and cannot be increased due to size limitations. However, there is a problem that the size of the vibration part 103 must be reduced.

  SUMMARY An advantage of some aspects of the invention is to solve at least a part of the problems described above, and the invention can be implemented as the following forms or application examples.

  [Application Example 1] A piezoelectric vibrating piece according to this application example includes a thick part, and a vibration part connected to the thick part by providing a step on at least one main surface, and formed thinner than the thick part. A piezoelectric vibrating piece in which the thick part and the vibrating part are formed by etching, wherein the thick part is formed on at least a part of an outer periphery of the one main surface and the one main part. A side wall portion that connects the other main surface facing the surface, the side wall portion is inclined from the one main surface to the other main surface side, and the end on the other main surface side is in plan view A first inclined surface formed on the outer side of the contour of the one main surface; and the other main surface is inclined toward the one main surface side, and an end on the one main surface side is the other in plan view A second inclined surface formed outside the contour of the main surface, and at least a part of the side wall portion, The one main surface in a first direction in which the end on the other main surface side of the surface abuts the end on the one main surface side of the second inclined surface and is substantially orthogonal to the one main surface. The distance from the surface to the end on the other main surface side of the first slope is the distance from the one main surface to the vibration surface on the one main surface side of the vibration part in the first direction. It is shorter.

According to this, the piezoelectric vibrating piece is formed by etching the thick portion and the vibrating portion, and the first inclined surface from one main surface in the first direction substantially orthogonal to one main surface of the thick portion. The distance from the other main surface side to the end on the other main surface side is shorter than the distance from the one main surface to the vibration surface on the one main surface side of the vibration part.
From this, the piezoelectric vibrating piece has a distance from the contour of one main surface of the first inclined surface of the side wall portion to the end on the other main surface side in the direction connecting the side wall portion and the vibrating portion in plan view, It can be shortened compared to the conventional case.

As a result, the piezoelectric vibrating piece can be made longer than the conventional one in the direction connecting the side wall portion and the vibrating portion, so that, for example, one main surface side of the thick portion is attached to the support member by an adhesive or the like. When fixed, the contact area of one main surface of the thick portion can be made wider than before.
Therefore, the piezoelectric vibrating piece can improve the fixing strength to the support member as compared with the related art.

  Further, in the piezoelectric vibrating piece, if the contact area of one main surface of the thick portion may be equal to that of the conventional one, the length of the thick portion in the direction connecting the side wall portion and the vibration portion can be made shorter than the conventional one. Therefore, the piezoelectric vibrating piece can be reduced in size when the size of the vibrating portion is the same as in the conventional case, and when the size of the vibrating portion is the same, the size of the vibrating portion is increased. Performance can be improved.

  [Application Example 2] The piezoelectric vibrating piece according to the application example described above is from the end on the one main surface side of the second inclined surface in a second direction connecting the side wall portion and the vibration portion in a plan view. It is preferable that the distance to the contour of the other main surface is substantially equal to the distance from the end on the other main surface side of the first inclined surface to the contour of the one main surface in the second direction.

According to this, the piezoelectric vibrating piece has a distance from the end on the one main surface side of the second inclined surface to the contour of the other main surface in the second direction connecting the side wall portion and the vibrating portion in plan view. The distance from the other principal surface side end of the first slope to the contour of one principal surface is approximately equal.
Therefore, in the piezoelectric vibrating piece, the second inclined surface and the first inclined surface of the thick part in the second direction are approximately equal in length, so that the thick part is etched from both sides substantially simultaneously. The first slope and the second slope of the thick part can be formed by one etching.

  Application Example 3 In the piezoelectric vibrating piece according to the application example described above, the distance from the one main surface to the vibration surface on the one main surface side of the vibration unit in the first direction is In this direction, it is preferable that the distance is longer than the distance from the other main surface to the vibration surface on the other main surface side of the vibration part.

According to this, in the first direction, the piezoelectric vibrating piece has a distance from one main surface to the vibration surface on the one main surface side in the first direction, and a distance from the other main surface to the vibration surface on the other main surface side. Longer.
From this, for example, when the thick portion is fixed to the support member with an adhesive or the like, the piezoelectric vibrating piece is fixed on one main surface side that is farther from the vibration portion than the other main surface side. Inhibition of main vibration of the vibration part can be reduced.

  Application Example 4 A piezoelectric device according to this application example is a piezoelectric device including the piezoelectric vibrating piece according to any one of Application Examples 1 to 3, and the one of the thick portions of the piezoelectric vibrating piece. The main surface side is fixed to the support member.

  According to this, in the piezoelectric device, one main surface side of the thick portion of the piezoelectric vibrating piece is fixed to the support member. From this, the piezoelectric device can reduce the inhibition of the main vibration of the vibration part by fixing one main surface side away from the vibration part.

  Application Example 5 A method of manufacturing a piezoelectric vibrating piece according to this application example includes a thick portion and a vibrating portion that is connected to the thick portion and is thinner than the thick portion. The thick portion and the vibration A method for manufacturing a piezoelectric vibrating piece in which a portion is formed by etching, wherein a vibrating portion forming step of etching one main surface of a piezoelectric substrate to form the vibrating portion, and both main surfaces of the piezoelectric substrate are formed. A thick part forming step for etching to form the thick part connected to the vibrating part, and a dividing step for dividing the piezoelectric vibrating piece having the thick part and the vibrating part from the piezoelectric substrate into individual pieces. It is characterized by having.

According to this, in the method of manufacturing the piezoelectric vibrating piece, one main surface of the piezoelectric substrate is etched to form a vibrating portion, and both the main surfaces of the piezoelectric substrate are etched to form a thick portion connected to the vibrating portion. A piezoelectric vibrating piece having a thick portion and a vibrating portion is formed and divided into individual pieces from the piezoelectric substrate.
Thus, the piezoelectric vibrating piece manufacturing method can provide the piezoelectric vibrating piece having the functions and effects described in Application Examples 1 and 2.

  Application Example 6 In the method for manufacturing a piezoelectric vibrating piece according to the application example, it is preferable that the thick portion forming step is performed after the vibrating portion forming step.

  According to this, since the manufacturing method of the piezoelectric vibrating piece performs the thick portion forming step after the vibrating portion forming step, the piezoelectric vibrating piece having the functions and effects described in Application Example 1 is obtained by performing the etching twice. Can be provided.

  Application Example 7 In the method for manufacturing a piezoelectric vibrating piece according to the application example, it is preferable that the vibrating part forming step and the thick part forming step are performed substantially simultaneously.

  According to this, the method for manufacturing a piezoelectric vibrating piece performs the vibration part forming step and the thick part forming step substantially simultaneously, and thus has the operations and effects described in Application Examples 1 and 2 with a single etching. A piezoelectric vibrating piece can be provided. As a result, the piezoelectric vibrating piece manufacturing method can improve the productivity of the piezoelectric vibrating piece as compared with Application Example 6.

The schematic diagram which shows the structure of the crystal vibrating piece of this embodiment. The principal part expanded sectional view of FIG.1 (b). The schematic diagram which shows the structure of the AT cut quartz crystal substrate in which multiple crystal vibrating pieces of this embodiment were formed. The schematic cross section explaining the manufacturing method of the crystal vibrating piece of this embodiment in order of a process. Sectional drawing of the quartz crystal vibrating piece of a modification. Sectional drawing which shows schematic structure of a crystal oscillator. FIG. 6 is a schematic diagram illustrating an example of a conventional piezoelectric vibrating piece. FIG. 10 is a schematic cross-sectional view showing a conventional method for manufacturing a piezoelectric vibrating piece.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
(Embodiment)
FIG. 1 is a schematic diagram illustrating a configuration of a crystal vibrating piece as an example of a piezoelectric vibrating piece according to the present embodiment. FIG. 1A is a plan view, and FIG. 1B is a cross-sectional view taken along the line AA in FIG. FIG. 2 is an enlarged cross-sectional view of the main part of FIG. 1B, and FIG. 2A and FIG.

As shown in FIG. 1, the quartz crystal resonator element 1 has a rectangular shape in plan view, and has a frame-shaped frame portion 2 as a thick portion and a step on one main surface 2 a of the frame portion 2. Thus, the vibration portion 3 is connected to the inside of the frame portion 2 and formed thinner than the frame portion 2.
The quartz crystal vibrating piece 1 is formed by etching using an AT cut quartz crystal substrate as an example of a piezoelectric substrate. Further, the quartz crystal vibrating piece 1 is obtained by forming a plurality of batches on the AT-cut quartz crystal substrate and then dividing them into pieces. The details of the method for manufacturing the quartz crystal vibrating piece 1 will be described later.

The frame portion 2 of the crystal vibrating piece 1 has a side wall portion 2c that connects one main surface 2a and the other main surface 2b opposite to the one main surface 2a on the outer periphery. Side wall 2c is formed by etching one main surface 2a and the other main surface 2b from the state of the AT-cut quartz crystal substrate.
In addition, the thickness of the frame part 2 (AT cut quartz substrate) is appropriately set in the range of about several tens μm to 100 μm. Moreover, one main surface 2a and the other main surface 2b of the frame part 2 are finished in a mirror state by polishing.

As shown in FIG. 1B, the side wall 2c is inclined from one main surface 2a to the other main surface 2b side, and the end 2f on the other main surface 2b side is one main surface 2a in plan view. The first slope 2d is formed outside the contour 2i.
Further, the side wall 2c is inclined from the other main surface 2b to the one main surface 2a side, and an end 2g on the one main surface side is formed outside the contour 2j of the other main surface 2b in plan view. It has the 2nd slope 2e.
In the side wall 2c, an end 2f on the other main surface 2b side of the first inclined surface 2d and an end 2g on the one main surface 2a side of the second inclined surface 2e are in contact with each other. This abutting position is a position about half the thickness of the frame portion 2.

Thereby, as shown in FIG.1 (b), the cross-sectional shape of the side wall part 2c of the frame part 2 is the center part of the thickness of the frame part 2 from one main surface 2a of the frame part 2, and the other main surface 2b. It is formed in a wedge shape that gradually protrudes to the outside of the quartz crystal vibrating piece 1 as it approaches.
As shown in FIG. 1A, a connection portion 4 that is cut when the crystal vibrating piece 1 is divided into individual pieces from the AT-cut quartz substrate is formed on a part of the side wall portion 2c of the frame portion 2. Is formed.

  The vibration part 3 is formed by etching one main surface 2a from the state of the AT-cut quartz substrate. The thickness of the vibration part 3 is appropriately set in a range of several μm to several tens of μm depending on a desired frequency.

The first inclined surface 2d, the second inclined surface 2e of the side wall 2c of the frame 2 and the side wall 2h of the frame 2 on the vibration unit 3 side are in relation to one main surface 2a or the other main surface 2b. The reason why the film is formed at an inclination rather than a right angle is due to the etching anisotropy with respect to the crystal axis of the crystal.
Although the degree of inclination varies depending on the orientation of each side wall with respect to the crystal axis of the AT-cut quartz crystal substrate, in the present embodiment, the degree of inclination will be described as uniform for easy understanding.

  Here, the side wall 2c extends from one main surface 2a to the end 2f on the other main surface 2b side of the first inclined surface 2d in the first direction substantially orthogonal to the one main surface 2a of the frame portion 2. The distance L1 is shorter than the distance L2 from the one main surface 2a to the vibration surface 3a on the one main surface 2a side in the first direction in the first direction.

As a result, as shown in FIG. 2A, the quartz crystal resonator element 1 includes a side wall portion 2c and a vibrating portion in a plan view as compared with a conventional frame portion indicated by a two-dot chain line having the same outer size L3. The distance L4 from the contour 2i of one main surface 2a of the first inclined surface 2d of the frame portion 2 to the end 2f on the other main surface 2b side in the second direction connecting 3 is compared with the conventional distance L5. And shortened.
Therefore, in the crystal vibrating piece 1, the length L6 of one main surface 2a of the frame 2 is longer than the conventional length L7.

As described above, in the quartz crystal resonator element 1 of the present embodiment, the frame portion 2 and the vibration portion 3 are formed by etching, and the first inclined surface 2d from one main surface 2a in the first direction of the frame portion 2 is formed. The distance L1 to the end 2f on the other main surface 2b side is shorter than the distance L2 from the one main surface 2a to the vibration surface 3a on the one main surface 2a side of the vibration part 3.
From this, the quartz crystal resonator element 1 can shorten the distance L4 from the outline 2i of the one main surface 2a of the first inclined surface 2d of the frame portion 2 to the end 2f on the other main surface 2b side as compared with the related art.

Thereby, since the length L6 of the one main surface 2a of the frame part 2 becomes longer than the conventional length L7, the crystal vibrating piece 1 has, for example, an adhesive or the like on the one main surface 2a side of the frame part 2. Therefore, the contact area of one main surface 2a of the frame portion 2 can be made wider than before when being fixed to the support member.
Therefore, the quartz crystal resonator element 1 can improve the fixing strength to the support member as compared with the related art.

Further, as shown in FIG. 2B, the quartz crystal resonator element 1 is indicated by a two-dot chain line if the contact area of one main surface 2a of the frame portion 2 may be equal to the conventional one (L6 = L7). Compared to the conventional frame portion, the length L8 of the frame portion 2 can be made shorter than the conventional length by the difference between the distance L5 and the distance L4.
From this, the crystal resonator element 1 can reduce the outer size L3 when the size L9 of the vibrating unit 3 is the same as the conventional size, and the vibrating unit 3 when the outer size L3 is the same. The size L9 of 3 can be increased to improve the performance.

The crystal vibrating piece 1 has a frame portion 2 when the distance L1 from one main surface 2a to the end 2f on the other main surface 2b side of the first inclined surface 2d is about half the thickness of the frame portion 2. From the distance L4 from the contour 2i of one main surface 2a of the first inclined surface 2d to the end 2f on the other main surface 2b side, and the contour 2j of the other main surface 2b of the second inclined surface 2e of the frame 2 The distance L4 ′ to the end 2g on the one main surface 2a side is substantially equal.
As a result, the quartz crystal resonator element 1 is formed by etching the frame portion 2 from the one main surface 2a side and the other main surface 2b side substantially simultaneously, so that the first inclined surface 2d of the frame portion 2 2 slopes 2e.

Here, a manufacturing method of the crystal vibrating piece 1 will be described with reference to FIGS.
FIG. 3 is a schematic diagram showing a configuration of an AT-cut quartz substrate on which a plurality of quartz vibrating pieces 1 are formed. 3A is a plan view, and FIG. 3B is a cross-sectional view taken along line BB in FIG. 3A. FIG. 4 is a schematic cross-sectional view for explaining the manufacturing method of the crystal vibrating piece 1 in the order of steps.

  As shown in FIG. 3, a plurality of crystal vibrating pieces 1 (9 in FIG. 3) are collectively formed on a rectangular AT-cut quartz substrate 5 in a grid shape. The crystal resonator element 1 is connected to the AT-cut crystal substrate 5 by the connecting portion 4. Around the crystal vibrating piece 1, a lattice portion 5 a that connects the connection portions 4 is formed.

[Vibration part forming process]
First, as shown in FIG. 4A, a region other than the region where the vibration part 3 is formed on one main surface 2 a of the AT-cut quartz crystal substrate 5 is patterned using a photolithography technique, and a resist 6 is used. Mask it.
Next, the entire area of the other main surface 2 b is masked with the resist 7.

Next, as shown in FIG. 4B, the AT cut quartz crystal substrate 5 is immersed in an etching solution (not shown), and one main surface 2 a is etched to form the vibrating portion 3. After the etching, the resists 6 and 7 are once peeled off to clean the AT-cut quartz crystal substrate 5.
Note that a hydrofluoric acid-containing liquid such as a hydrofluoric acid liquid or a buffered hydrofluoric acid liquid that is a mixed liquid of ammonium fluoride and hydrofluoric acid is used as the etching liquid.

[Frame part forming step]
Next, as shown in FIG. 4C, the region of the vibrating portion 3, the region where the frame portion 2 is formed, and the region where the lattice portion 5a is formed on one main surface 2a of the AT-cut quartz crystal substrate 5. Then, patterning is performed using a photolithography technique, and masking is performed using a resist 6.
Next, using the photolithography technique, the region of the vibrating portion 3, the region where the frame portion 2 is formed, and the region where the lattice portion 5a is formed are formed on the other main surface 2b of the AT-cut quartz crystal substrate 5 in the same manner as described above. Patterning and masking with a resist 7.

Next, as shown in FIG. 4 (d), the AT-cut quartz crystal substrate 5 is immersed in an etching solution, and one main surface 2a and the other main surface 2b are etched to form the frame portion 2 and the lattice portion 5a. To do.
Next, the resists 6 and 7 are peeled off to obtain the crystal vibrating piece 1 in a state where a plurality of AT cut crystal substrates 5 shown in FIG. 3 are formed.

[Division process]
Next, an electrode (not shown) is formed on the crystal vibrating piece 1 and frequency adjustment is performed. Then, the connection portion 4 between the AT cut crystal substrate 5 and the crystal vibrating piece 1 is cut with a cutting device or the like, and the AT cut crystal substrate 5 is cut. The crystal vibrating piece 1 is divided into individual pieces.
Through these steps, the crystal vibrating piece 1 shown in FIG. 1 is obtained.

As described above, in the method of manufacturing the crystal vibrating piece 1, the vibration portion 3 is formed by etching one main surface 2 a of the AT cut crystal substrate 5, and both main surfaces 2 a and 2 b of the AT cut crystal substrate 5 are formed. The frame portion 2 connected to the vibration portion 3 is formed by etching, and the crystal vibrating piece 1 is divided into individual pieces from the AT-cut quartz substrate 5.
Thereby, the manufacturing method of the quartz crystal vibrating piece 1 can provide the quartz crystal vibrating piece 1 having the above-described effects by two etchings.

In addition, as shown in FIG.4 (d), if the desired thickness T1 of the vibration part 3 is half or less of the thickness T2 of the AT cut quartz crystal substrate 5, as shown in FIG. It is possible to carry out the frame portion forming process all at once by performing a single etching.
That is, the method for manufacturing the quartz crystal vibrating piece 1 starts the etching of the vibrating part 3 and the etching of the frame part 2 almost simultaneously, and etches both the main surfaces 2a and 2b of the frame part 2 to form the first inclined surface 2d and The second inclined surface 2e is connected to a position half the thickness T2 of the AT-cut quartz crystal substrate 5, and when the side wall portion 2c is formed, the thickness of the vibrating portion 3 is half of T2.

Therefore, in the method for manufacturing the quartz crystal vibrating piece 1, if the desired thickness T <b> 1 of the vibrating portion 3 is half of the thickness T <b> 2 of the AT cut quartz crystal substrate 5, both steps are finished here.
In addition, if the desired thickness T1 of the vibrating portion 3 is thinner than half the thickness T2 of the AT-cut quartz substrate 5, the manufacturing method of the crystal vibrating piece 1 continues the etching of the vibrating portion 3 and the etching of the frame portion 2. Both steps are finished when the thickness of the vibration part 3 reaches the desired thickness T1.

According to this, since the manufacturing method of the crystal vibrating piece 1 can perform the vibration part forming process and the frame part forming process all at once by one etching, the manufacturing time of the crystal vibrating piece 1 is shortened. can do. Thereby, the manufacturing method of the crystal vibrating piece 1 improves the productivity of the crystal vibrating piece 1.
In addition, you may reverse the order of a vibration part formation process and a frame part formation process.

Here, the modification of the said embodiment is demonstrated.
(Modification)
FIG. 5 is a cross-sectional view of a modified quartz crystal resonator element. In addition, the same code | symbol is attached | subjected to a common part with the said embodiment, and the description is abbreviate | omitted.

  As shown in FIG. 5, the crystal resonator element 101 according to the modification has a distance L <b> 2 from one main surface 2 a of the frame portion 2 to the vibration surface 3 a on the one main surface 2 a side of the vibration portion 3 in the first direction. However, it is formed to be longer than the distance L10 from the other main surface 2b of the frame portion 2 to the vibration surface 3b on the other main surface 2b side of the vibration portion 3 in the first direction.

  According to this, for example, when the frame 2 is fixed to the support member with an adhesive or the like, the crystal vibrating piece 101 has one main surface 2a side farther from the vibration unit 3 than the other main surface 2b side. By fixing, inhibition of the main vibration of the vibration part 3 can be reduced.

  In the above-described embodiment and modification, the frame 2 is formed so as to surround all four sides of the vibration unit 3. However, the present invention is not limited to this, and the frame 2 includes at least the vibration unit 3. What is necessary is just to be formed connected to one side. Therefore, the frame part 2 may be formed so as to surround three sides of the vibration part 3, or may be formed so as to be connected to two opposite sides of the vibration part 3. The frame portion 2 may be formed so as to be connected to one side of the vibration portion 3.

Here, a quartz crystal resonator as an example of a piezoelectric device on which any one of the quartz crystal vibrating pieces 1 and 101 is mounted will be described with reference to FIG.
FIG. 6 is a cross-sectional view showing a schematic configuration of the crystal resonator. Note that electrodes provided in the crystal resonator are omitted. In addition, the same reference numerals are given to common parts with the above embodiment, and the description thereof is omitted.

As shown in FIG. 6, the crystal resonator 10 includes a crystal resonator element 1, a package 20, and the like.
The package 20 includes a base portion 21 as a support member, a lid (lid) portion 22, and a joint portion 23. The planar shape of the package 20 is formed in a substantially rectangular shape.

For the base portion 21, a ceramic green sheet is formed, laminated and fired, and an aluminum oxide sintered body or the like is used.
The lid portion 22 is made of a metal such as kovar, and is seam welded to a joint portion 23 made of a metal such as kovar in a state where the crystal vibrating piece 1 is accommodated in the package 20. The joint portion 23 is joined to the base portion 21 by brazing or the like.
As a result, the inside of the package 20 of the crystal unit 10 is hermetically sealed. Note that the inside of the package 20 is sealed with a vacuum or an inert gas such as nitrogen, helium, or argon.

The quartz crystal vibrating piece 1 is mounted on the bottom surface 21 a of the base portion 21 via an adhesive 30. At this time, in the crystal resonator 10, one main surface 2 a side of the frame portion 2 of the crystal resonator element 1 is fixed to the bottom surface 21 a of the base portion 21 with an adhesive 30.
As a result, the crystal unit 10 is fixed on the side of the main surface 2a that is separated from the side of the other main surface 2b of the frame 2 from the vibration unit 3 of the crystal resonator element 1, thereby Inhibition of main vibration can be reduced.

  The crystal resonator 10 may use a crystal vibrating piece 101 instead of the crystal vibrating piece 1. Moreover, although the said embodiment demonstrated taking the crystal resonator as an example as a piezoelectric device, it is not limited to this, It can apply also to a crystal oscillator, a crystal filter, etc.

  DESCRIPTION OF SYMBOLS 1 ... Crystal vibrating piece as a piezoelectric vibrating piece, 2 ... Frame part as thick part, 2a ... One main surface, 2b ... The other main surface, 2c ... Side wall part, 2d ... 1st slope, 2e ... 1st 2f, 2f ... end on the other main surface side of the first slope, 2g ... end on one main surface side of the second slope, 2h ... side wall, 2i ... contour of one main surface, 2j ... Outline of the other main surface, 3... Vibration part, 3a... Vibration surface, L1... Distance from one main surface to the end of the first slope, L2.

The present invention relates to a method for manufacturing a resonator element .

A method for manufacturing a resonator element according to a first aspect of the present invention is a method for manufacturing a resonator element including a vibrating portion and a thick portion that supports the vibrating portion integrally and is thicker than the vibrating portion. A method of etching a substrate from one main surface side to form a thin portion corresponding to the vibrating portion; and a region corresponding to the thick portion in the etched substrate; Masking the front and back main surfaces of the thin portion and etching a vibrating piece forming step of exposing the portion of the substrate exposed from the mask; and dividing step of dividing the vibrating piece into individual pieces from the etched substrate The vibrating piece forming step is performed after the thin portion forming step.
In the method of manufacturing the resonator element according to the second aspect of the invention, the outer periphery of the thick portion extends from one main surface to the other main surface of the thick portion, The side wall includes a first end portion on the other main surface side of the first inclined surface and a second end surface on the one main surface side of the second inclined surface. The thin portion forming step includes a first portion in a direction orthogonal to the one main surface, and the thin portion is formed from the one main surface side to the thin portion. Etching is performed so that the distance along one direction is L2, and the vibrating piece forming step is performed so that the distance along the first direction from the one main surface side to the connection portion is L1. When etched, L1 <L2 is satisfied.
In the method for manufacturing a resonator element according to the third aspect of the present invention, in the resonator element forming step, the one of the second inclined surfaces in a second direction connecting the side wall and the vibrating portion in a plan view. The distance from the main surface side end of the first main surface side to the contour of the other main surface in the second direction from the other main surface side end of the first inclined surface to the contour of the one main surface Etching is performed to be approximately equal to the distance.
In the method for manufacturing the resonator element according to the fourth aspect of the invention, the distance along the first direction from the other principal surface side to the vibrating portion is L10 after the thin portion forming step. When the thin portion is etched from the other main surface side, L10 <L2 is satisfied.
[Application Example 1] A piezoelectric vibrating piece according to this application example includes a thick part, and a vibration part connected to the thick part by providing a step on at least one main surface, and formed thinner than the thick part. A piezoelectric vibrating piece in which the thick part and the vibrating part are formed by etching, wherein the thick part is formed on at least a part of an outer periphery of the one main surface and the one main part. A side wall portion that connects the other main surface facing the surface, the side wall portion is inclined from the one main surface to the other main surface side, and the end on the other main surface side is in plan view A first inclined surface formed on the outer side of the contour of the one main surface; and the other main surface is inclined toward the one main surface side, and an end on the one main surface side is the other in plan view A second inclined surface formed outside the contour of the main surface, and at least a part of the side wall portion, The one main surface in a first direction in which the end on the other main surface side of the surface abuts the end on the one main surface side of the second inclined surface and is substantially orthogonal to the one main surface. The distance from the surface to the end on the other main surface side of the first slope is the distance from the one main surface to the vibration surface on the one main surface side of the vibration part in the first direction. It is shorter.

Claims (7)

A thick portion, and a vibration portion connected to the thick portion and formed thinner than the thick portion by providing a step on at least one main surface, and the thick portion and the vibration portion are A piezoelectric vibrating piece formed by etching,
The thick portion has, on at least a part of the outer periphery, a side wall portion connecting the one main surface and the other main surface facing the one main surface,
The side wall portion is inclined from the one main surface toward the other main surface, and an end on the other main surface side is formed outside the outline of the one main surface in a plan view. The slope,
A second inclined surface that is inclined from the other principal surface to the one principal surface side, and an end on the one principal surface side is formed outside the outline of the other principal surface in a plan view. And
In at least a part of the side wall, an end on the other main surface side of the first inclined surface and an end on the one main surface side of the second inclined surface are in contact with each other,
In the first direction substantially orthogonal to the one main surface, the distance from the one main surface to the end on the other main surface side of the first slope is the one direction in the first direction. A piezoelectric vibrating piece having a length shorter than a distance from a main surface to a vibration surface on the one main surface side of the vibration unit.   2. The piezoelectric resonator element according to claim 1, wherein an end of the second inclined surface from the one main surface side in the second direction connecting the side wall portion and the vibrating portion in a plan view is the other main surface. The piezoelectric vibrating piece is characterized in that a distance to the contour of the first inclined surface in the second direction is substantially equal to a distance from the end on the other principal surface side of the first inclined surface to the contour of the one principal surface. .   3. The piezoelectric vibrating piece according to claim 1, wherein a distance from the one main surface to the vibration surface on the one main surface side of the vibration unit in the first direction is the first direction. The piezoelectric vibrating piece is longer than the distance from the other main surface to the vibration surface on the other main surface side of the vibrating portion.   4. A piezoelectric device including the piezoelectric vibrating piece according to claim 1, wherein the one main surface side of the thick portion of the piezoelectric vibrating piece is fixed to a support member. A characteristic piezoelectric device. A method of manufacturing a piezoelectric vibrating piece having a thick part and a vibrating part connected to the thick part and thinner than the thick part, wherein the thick part and the vibrating part are formed by etching,
A vibrating part forming step of etching one main surface of the piezoelectric substrate to form the vibrating part;
A thick part forming step of etching both main surfaces of the piezoelectric substrate to form the thick part connected to the vibrating part;
A method of manufacturing a piezoelectric vibrating piece, comprising: a dividing step of dividing the piezoelectric vibrating piece having the thick portion and the vibrating portion from the piezoelectric substrate into individual pieces.   6. The method of manufacturing a piezoelectric vibrating piece according to claim 5, wherein the thick portion forming step is performed after the vibrating portion forming step.   6. The method of manufacturing a piezoelectric vibrating piece according to claim 5, wherein the vibrating portion forming step and the thick portion forming step are performed substantially simultaneously.

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