JP2013197621A - Vibration piece, vibrator, oscillator, electronic apparatus, and method of manufacturing vibration piece - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vibration piece having excellent vibration characteristics.SOLUTION: A vibration piece has a crystal substrate 3 and a conductor pattern formed on the crystal substrate 3. The crystal substrate 3 has a vibration part and a thin part disposed around the vibration part. The vibration part has a first protrusion 35 protruding from the thin part toward a +Y' axis side, and a second protrusion 37 protruding toward a -Y' axis side. An end A1 of a major surface 351 of the first protrusion 35 located on a +Z' axis side is located overlappingly in a Y' axis direction with a side surface 373 of the second protrusion 37 located on a +Z' axis side with respect to a major surface 371 thereof. An end A3 of the major surface 371 of the second protrusion 37 located on a -Z' axis side is located overlappingly in the Y' axis direction with a side surface 353 of the first protrusion 35 located on the -Z' axis side with respect to a major surface 351 thereof.

Description

  The present invention relates to a resonator element, a vibrator, an oscillator, an electronic device, and a method for manufacturing the resonator element.

  Conventionally, a resonator element (a vibrator or a transmitter) using quartz is known. Such a resonator element is widely used as a reference frequency source, an oscillation source, and the like for various electronic devices because of its excellent frequency-temperature characteristics. In particular, a resonator element using a quartz crystal substrate cut at a cut angle called AT cut has a frequency-temperature characteristic that exhibits a cubic curve, and is therefore widely used in mobile communication devices such as mobile phones (for example, , See Patent Document 1).

As disclosed in Patent Document 1, a so-called bi-mesa type resonator element using an AT-cut quartz crystal substrate is known. The bi-mesa type has a thick vibrating portion and a thin portion that is provided along the periphery of the vibrating portion and is thinner than the thickness of the vibrating portion, and the vibrating portion is on the + Y ′ axis side from the thin portion. The shape which has the 1st convex part which protrudes in (2), and the 2nd convex part which protrudes in the -Y 'axial side is said. Such a shape has an advantage that excellent vibration characteristics can be obtained because vibration can be efficiently confined in the vibration part.
Here, as a method for forming a bi-mesa type quartz substrate, for example, a method of patterning a plate-like quartz substrate by a photolithography technique and an etching technique can be mentioned.

  Specifically, first, a plate-like crystal substrate cut out by AT cut is prepared, and a first mask M1 ′ corresponding to the first convex portion is formed on one surface thereof, and a second mask is formed on the other surface. A second mask M2 ′ corresponding to the convex portion is formed. The first and second masks M1 'and M2' have the same shape and are formed so that their outlines overlap each other. Next, the quartz crystal substrate is etched from both sides through the first and second masks M1 ′ and M2 ′, so that the vibrating portion having the first and second convex portions 51 and 52 and the periphery thereof are located. A quartz substrate having a thin portion is formed. Next, a crystal vibrating piece is obtained by forming electrodes on the surface of the obtained crystal substrate.

  However, in the etching process of the quartz substrate, as shown in FIG. 13, the side surface 512 on the + Z′-axis side of the first protrusion 51 is −Z from the end on the + Z′-axis side of the first mask M1 ′ by side etching. Similarly, the side surface 522 on the −Z′-axis side of the second convex portion 52 is formed on the side of the −Z′-axis side of the second mask M2 ′ by the side etching. Formed to penetrate into. By such side etching, the first convex portion 51 and the second convex portion 52 are displaced in the Z′-axis direction. This deviation causes an unnecessary vibration mode (vibration other than the thickness-shear vibration mode) or the vibration cannot be confined, resulting in deterioration of vibration characteristics.

JP 2010-147625 A JP 2008-067345 A

  An object of the present invention is to provide a resonator element having excellent vibration characteristics, a highly reliable vibrator, an oscillator and an electronic device including the resonator element, and a method for manufacturing the resonator element having excellent vibration characteristics. It is in.

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 application examples.
[Application Example 1]
The resonator element according to the aspect of the invention includes a first convex portion projecting on one main surface side of the substrate and a second convex portion projecting on the other main surface side on the back surface side with respect to the one main surface side of the substrate. A substrate including: a vibrating portion including: a thin portion that is disposed along an outer edge of the vibrating portion and is thinner than the thickness of the vibrating portion;
The first convex portion is inclined with respect to the main surface of the first convex portion, faces the first side surface in a predetermined direction, and is perpendicular to the main surface of the first convex portion. A second side which is
The second convex portion has a third side surface perpendicular to the main surface of the second convex portion, and faces the third side surface in the predetermined direction, and is inclined with respect to the main surface of the first convex portion. A fourth side surface,
The second side surface is disposed so as to overlap the fourth side surface in plan view in the thickness direction of the substrate,
The third side surface is arranged to overlap the first side surface in a plan view in the thickness direction of the substrate.
Thereby, the shift | offset | difference of the predetermined direction of a 1st convex part and a 2nd convex part is suppressed, and it can suppress that an unnecessary vibration mode generate | occur | produces in a vibration part. Moreover, the generated vibration (energy) can be effectively confined in the vibration part. Therefore, a resonator element having excellent vibration characteristics can be obtained.

[Application Example 2]
The resonator element according to the aspect of the invention includes a vibrating portion including a first convex portion protruding toward the + Y′-axis side and a second convex portion protruding toward the −Y′-axis side, and is disposed along an outer edge of the vibrating portion. A rotating Y-cut quartz crystal substrate including a thin portion having a thickness smaller than the thickness of the vibrating portion;
Including a conductor pattern disposed on the quartz substrate,
An end on the + Z′-axis side of the main surface of the first convex portion is arranged so as to overlap with a side surface located on the + Z′-axis side of the main surface of the second convex portion in a plan view in the Y′-axis direction. And
An end on the −Z′-axis side of the main surface of the second convex portion overlaps with a side surface located on the −Z′-axis side of the main surface of the first convex portion in a plan view in the Y′-axis direction. It is characterized by being arranged in.
Thereby, the shift | offset | difference of the Z'-axis direction of a 1st convex part and a 2nd convex part is suppressed, and it can suppress that an unnecessary vibration mode generate | occur | produces in a vibration part. Moreover, the generated vibration (energy) can be effectively confined in the vibration part. Therefore, a resonator element having excellent vibration characteristics can be obtained.

[Application Example 3]
In the resonator element according to the aspect of the invention, the angle formed between the −Z′-axis side side surface of the first convex portion and the main surface of the first convex portion may be the same as that between the + Z′-axis side side surface of the first convex portion and the first convex portion. Smaller than the angle formed with the main surface of one convex part,
The angle formed between the side surface on the + Z′-axis side of the second convex portion and the main surface of the second convex portion is the side surface on the −Z′-axis side of the second convex portion and the main surface of the second convex portion. It is preferably smaller than the angle formed by
Thereby, the side surface of the main surface of the first convex portion on the + Z′-axis side is more reliably positioned on the + Z′-axis side of the main surface of the second convex portion in plan view in the Y′-axis direction. The end of the main surface of the second convex portion on the −Z′-axis side is the −Z ′ axis of the main surface of the first convex portion in plan view in the Y′-axis direction. It can arrange | position so that it may overlap with the side surface located in the side.

[Application Example 4]
In the resonator element according to the aspect of the invention, the side surface on the + Z′-axis side of the first convex portion is perpendicular to the main surface of the first convex portion,
The side surface on the −Z′-axis side of the second convex portion is preferably perpendicular to the main surface of the second convex portion.
Thereby, the shift | offset | difference of the Z'-axis direction of a 1st convex part and a 2nd convex part can be suppressed easily and reliably.

[Application Example 5]
In the resonator element according to the aspect of the invention, the end on the + Z′-axis side of the main surface of the first convex portion may intersect the plane that bisects the thickness of the second convex portion on the + Z′-axis side of the second convex portion. Is arranged so as to overlap with the end of the Y in the plan view in the Y′-axis direction,
An end on the −Z′-axis side of the main surface of the second convex portion is an end on the −Z′-axis side of the first convex portion that intersects a plane that bisects the thickness of the first convex portion, and Y 'It is preferable that they are arranged so as to overlap in a plan view in the axial direction.
Thereby, the resonator element having more excellent vibration characteristics is obtained.

[Application Example 6]
In the resonator element according to the aspect of the invention, it is preferable that the crystal substrate is an AT-cut crystal substrate.
As a result, the resonator element having excellent frequency characteristics is obtained.
[Application Example 7]
The vibrator of the present invention includes the resonator element of the present invention,
And a package in which the vibrating piece is accommodated.
Thereby, a vibrator having excellent reliability can be obtained.

[Application Example 8]
The oscillator of the present invention includes the resonator element of the present invention,
And an oscillation circuit that is electrically connected to the resonator element.
Thereby, an oscillator having excellent reliability can be obtained.
[Application Example 9]
An electronic apparatus according to the present invention includes the resonator element according to the present invention.
Thereby, an electronic device having excellent reliability can be obtained.

[Application Example 10]
The method of manufacturing the resonator element according to the invention includes a step of preparing a rotating Y-cut quartz substrate,
A first mask is disposed on the main surface on the + Y′-axis side of the quartz substrate, and the first mask is disposed on the main surface on the −Y′-axis side so as to be shifted to the −Z′-axis side with respect to the first mask. By arranging two masks and etching the quartz substrate exposed from the first mask and the second mask, a first convex portion protruding to the + Y′-axis side and a −Y′-axis are formed on the quartz substrate. Forming a mesa substrate including a vibrating portion including a second convex portion protruding to the side, and a thin portion having a thickness smaller than the thickness of the vibrating portion disposed along an outer edge of the vibrating portion;
Forming a conductor pattern on the mesa substrate.
Thereby, the resonator element having excellent vibration characteristics can be manufactured easily and reliably.

FIG. 3 is a plan view of the vibrator according to the first embodiment of the invention. It is the sectional view on the AA line in FIG. FIG. 2 is a plan view of a resonator element included in the vibrator illustrated in FIG. 1, in which (a) is a top view and (b) is a bottom view. It is the BB sectional view taken on the line in FIG. FIG. 4 is a cross-sectional view for explaining a method for manufacturing the resonator element shown in FIG. 3. FIG. 4 is a cross-sectional view for explaining a method for manufacturing the resonator element shown in FIG. 3. It is sectional drawing of the vibrator | oscillator concerning 2nd Embodiment of this invention. It is sectional drawing of the vibrator | oscillator concerning 3rd Embodiment of this invention. It is sectional drawing which shows an example of the oscillator of this invention. It is an electronic device (notebook type personal computer) provided with the resonator element according to the invention. It is an electronic device (cellular phone) including the resonator element according to the invention. It is an electronic device (digital still camera) provided with the resonator element according to the invention. It is sectional drawing for demonstrating a prior art.

Hereinafter, a resonator element, a vibrator, an oscillator, an electronic device, and a method of manufacturing the resonator element according to the invention will be described in detail based on preferred embodiments shown in the drawings.
First, a vibrator (vibrator of the present invention) to which the resonator element of the present invention is applied will be described.
<First Embodiment>
1 is a plan view of a vibrator according to the first embodiment of the present invention, FIG. 2 is a cross-sectional view taken along line AA in FIG. 1, and FIG. 3 is a plan view of a resonator element included in the vibrator shown in FIG. 4A is a top view, FIG. 4B is a cross-sectional view taken along the line BB in FIG. 1, and FIGS. 5 and 6 illustrate a method for manufacturing the resonator element shown in FIG. It is sectional drawing for demonstrating. In the following, for convenience of explanation, the upper side in FIG. 2 is referred to as “upper” and the lower side is referred to as “lower”.

1. Oscillator The vibrator 1 shown in FIGS. 1 and 2 includes a vibrating piece 2 (the vibrating piece of the present invention) and a package 9 that houses the vibrating piece 2. Hereinafter, the resonator element 2 and the package 9 will be sequentially described in detail.
(package)
The package 9 includes a box-shaped base 91 having a recess 911 that opens to the upper surface, and a plate-shaped lid 92 that is joined to the base 91 so as to close the opening of the recess 911. Such a package 9 has a storage space S formed by closing the concave portion 911 with the lid 92, and the resonator element 2 is stored and installed in the storage space S in an airtight manner. . The storage space S may be in a reduced pressure (preferably vacuum) state, or may be filled with an inert gas such as nitrogen, helium, or argon. Thereby, the vibration characteristics of the resonator element 2 are improved.

  The constituent material of the base 91 is not particularly limited, but various ceramics such as aluminum oxide can be used. The constituent material of the lid 92 is not particularly limited, but may be a member whose linear expansion coefficient approximates that of the constituent material of the base 91. For example, when the constituent material of the base 91 is ceramic as described above, an alloy such as Kovar is preferable. The joining of the base 91 and the lid 92 is not particularly limited, and for example, the base 91 and the lid 92 may be joined via an adhesive or may be joined by seam welding or the like.

  A first connection terminal 95 and a second connection terminal 96 are formed on the bottom surface of the recess 911. The first connection terminal 95 is formed facing a later-described first connection electrode 421 of the resonator element 2, and the first connection terminal 95 and the first connection electrode 421 are electrically connected via the conductive fixing member 71. Connected. Further, the second connection terminal 96 is formed so as to face a second connection electrode 422 (described later) of the resonator element 2, and the second connection terminal 96 and the second connection electrode 422 are interposed via the conductive fixing member 72. Are electrically connected.

The conductive fixing members 71 and 72 are not particularly limited. For example, solder, silver paste, conductive adhesive (adhesive in which conductive fillers such as metal particles are dispersed in a resin material), or the like is used. it can.
The first connection terminal 95 and the second connection terminal 96 are electrically connected to external terminals (mounting terminals) 94 formed on the bottom surface of the package 9 via vias (not shown).
The configurations of the first and second connection terminals 95 and 96 and the external terminal 94 are not particularly limited as long as they have conductivity. For example, a metallized layer such as Cr (chrome) or W (tungsten) is used. It can be composed of a metal film in which each film such as Ni (nickel), Au (gold), Ag (silver), Cu (copper) is laminated on the (underlayer).

(Vibration piece 2)
As shown in FIGS. 1 to 3, the resonator element 2 of the present embodiment includes a quartz substrate 3 and a conductor pattern 4 formed on the quartz substrate 3.
The quartz substrate 3 is a so-called rotating Y-cut quartz substrate whose vibration mode vibrates by thickness-shear vibration, and is constituted by, for example, an AT-cut quartz substrate. Thereby, it becomes the vibration piece 2 which can exhibit the outstanding frequency characteristic. The rotated Y-cut quartz substrate refers to a plane (Y plane) including the X-axis (electric axis) and the Z-axis (optical axis) which are crystal axes of quartz, counterclockwise (− It is a quartz substrate cut out so as to have a main surface (a main surface including the X axis and the Z ′ axis) obtained by rotating the Y axis (machine axis) direction by a predetermined angle α. In the quartz substrate 3 having such a configuration, the longitudinal direction of the quartz substrate 3 can be defined as the X axis, the short direction as the Z ′ axis, and the thickness direction as the Y ′ axis. In the case of an AT cut quartz substrate, the angle α is about 35 degrees 15 minutes.

  Such a quartz crystal substrate 3 has a thick vibrating portion 31 and a thin portion 32 thinner than the thickness of the vibrating portion 31 formed along the periphery of the vibrating portion 31. The vibration part 31 includes a first convex part 35 projecting from the thin part 32 to the + Y′-axis side and a second convex part 37 projecting to the −Y′-axis side. That is, the quartz substrate 3 has a bi-mesa type in which mesa portions are formed on both sides. According to such a shape, vibrations can be effectively confined in the vibration part 31, so that frequency characteristics such as CI value and Q value can be improved.

A first excitation electrode 411 is formed on the main surface 351 of the first convex portion 35, and a second excitation electrode 412 is formed on the main surface 371 of the second convex portion 37. Note that the first excitation electrode 411 and the second excitation electrode 412 are formed so that their outlines overlap each other in plan view of the resonator element 2.
A first connection electrode 421 and a second connection electrode 422 are formed side by side on the lower surface of the thin portion 32. The first excitation electrode 411 is electrically connected to the first connection electrode 421 via the first connection wiring 431 formed on the upper surface and the side surface of the crystal substrate 3, and the second excitation electrode 412 is connected to the crystal substrate 3. The second connection electrode 422 is electrically connected through a second connection wiring 432 formed on the lower surface of the first connection wire 432.

The first excitation electrode 411, the second excitation electrode 412, the first connection electrode 421, the second connection electrode 422, the first connection wiring 431, and the second connection wiring 432 constitute the conductor pattern 4.
As the configuration of the first excitation electrode 411, the second excitation electrode 412, the first connection electrode 421, the second connection electrode 422, the first connection wiring 431, and the second connection wiring 432, as long as they have conductivity, Although not particularly limited, for example, an electrode layer such as Ni (nickel), Au (gold), Ag (silver), or Cu (copper) is formed on a metallized layer (underlayer) such as Cr (chromium) or W (tungsten). It can be comprised with the laminated metal film.
Such a vibrating piece 2 is supported on the package 9 by conductive fixing members 71 and 72. Specifically, as described above, the first connection electrode 421 is fixed to the first connection terminal 95 via the conductive fixing member 71, and the first connection electrode 422 is connected to the first connection terminal 95 via the conductive fixing member 72. 2 is fixed to the connection terminal 96.

Next, the shape of the vibration part 31 is demonstrated in detail based on FIG. 4 is a cross-sectional view taken along line BB in FIG.
As shown in FIG. 4, the first convex portion 35 includes a main surface 351 configured by an XZ ′ plane (that is, a plane defined by the X axis and the Z ′ axis, and so on), and a main surface 351. The side surface (second side surface) 352 is located on the + Z′-axis side with respect to the main surface 351, and the side surface (first side surface) 353 is located on the −Z′-axis side with respect to the main surface 351. The side surface 352 is a first crystal surface of quartz and is a surface substantially perpendicular to the main surface 351. On the other hand, the side surface 353 is a second crystal surface of quartz and is a surface inclined with respect to the main surface 351. The angle θ1 formed between the main surface 351 and the side surface 353 is smaller than the angle θ2 formed between the main surface 351 and the side surface 352.

  Similarly, the second convex portion 37 includes a main surface 371 configured with an XZ ′ plane, a side surface (third side surface) 372 located on the −Z ′ axis side with respect to the main surface 371, and a main surface 371. And a side surface (fourth side surface) 373 located on the + Z ′ axis side. The side surface 372 is a first crystal surface of quartz and is a surface substantially perpendicular to the main surface 371. On the other hand, the side surface 373 is a second crystal surface of quartz and is a surface inclined with respect to the main surface 371. The angle θ3 formed by the main surface 371 and the side surface 373 is smaller than the angle θ4 formed by the main surface 371 and the side surface 372.

The side surface 353 being substantially perpendicular to the main surface 351 means that the angle θ formed by the main surface 351 and the side surface 353 is in a range of 85 ° ≦ θ ≦ 95 °. Similarly, that the side surface 373 is substantially perpendicular to the main surface 371 means that the angle θ formed by the main surface 371 and the side surface 373 is in the range of 85 ° ≦ θ ≦ 95 °.
The + Z′-axis end (the boundary between the main surface 351 and the side surface 352) A1 (side surface 352) of the main surface 351 of the first convex portion 35 is the side surface 373 of the second convex portion 37 and the Y′-axis in plan view. It is overlaid in the direction. In other words, the end A1 is the + Z′-axis end (the boundary between the main surface 371 and the side surface 373) A4 of the main surface 371 of the second convex portion 37 and the second convex in the Z′-axis direction in plan view. The side surface 373 of the portion 37 is located between the end on the + Z′-axis side (the boundary between the side surface 373 and the thin portion 32) B4. The term “between the end A4 and the end B4” includes the case where the end A1 overlaps the end A4 in the Y′-axis direction and the case where the end A4 overlaps the Y′-axis direction in plan view.

  In addition, the −Z′-axis end (the boundary between the main surface 371 and the side surface 372) A3 (side surface 372) of the main surface 351 of the second convex portion 37 is the same as the side surface 353 of the first convex portion 35 in plan view. It is located overlapping the Y 'axis. In other words, the end A3 is, in plan view, in the Z′-axis direction, the end on the −Z′-axis side of the main surface 351 of the first convex portion 35 (the boundary between the main surface 351 and the side surface 353) A2, and the first The side surface 353 of the convex portion 35 is located between the end on the −Z′-axis side (the boundary between the side surface 353 and the thin portion 32) B2. The term “between end A2 and end B2” includes the case where end A3 overlaps with end A2 in the Y′-axis direction and the case where end A2 overlaps with Y′-axis in plan view.

  By arranging the ends A1 and A3 as described above, the resonator element 2 having excellent vibration characteristics can be obtained. Specifically, the effective vibration region 359 in the first convex portion 35 is included in the first convex portion 35 in consideration of the volume load of the first convex portion 35, and bisects the thickness of the first convex portion 35. (XZ ′ plane) This is a region that coincides with F1. Similarly, the effective vibration region 379 in the first convex portion 37 is included in the second convex portion 37 in consideration of the volume load of the second convex portion, and is a surface (XZ ′) that bisects the thickness of the second convex portion 37. Plane) A region that coincides with F2. As described above, the displacement of the effective vibration regions 359 and 379 in the Z′-axis direction can be suppressed by positioning the end A1 so as to overlap the side surface 373 and positioning the end A3 so as to overlap the side surface 353. . Therefore, vibration (energy) generated in the vibration part 31 can be efficiently confined in the vibration part 31, and the vibration piece 2 can exhibit excellent vibration characteristics.

  The end A1 of the main surface 351 of the first convex portion 35 may be positioned so as to overlap the side surface 373 of the second convex portion 37 in the Y′-axis direction in plan view, but the + Z ′ axis of the plane F2 It is preferable that the side end overlaps with the Y′-axis direction. Similarly, the end A3 of the main surface 371 of the second convex portion 37 may be positioned so as to overlap the side surface 353 of the first convex portion 35 in the Y′-axis direction in plan view, but −Z of the plane F1. It is preferable to overlap with the 'axis end' in the Y'-axis direction. By disposing the ends A1 and A3 in this way, the displacement in the Z′-axis direction between the effective vibration region 359 of the first convex portion 35 and the effective vibration region 379 of the second convex portion 37 is made substantially zero. In other words, since the contours of the effective vibration regions 359 and 379 can be matched, the vibration generated in the vibration part 31 can be more efficiently confined in the vibration part 31 and more excellent vibration characteristics can be exhibited. It becomes the vibrating piece 2 that can be made.

  Here, since the side surface 352 of the first convex portion 35 is composed of a surface perpendicular to the main surface 351, the end A1 of the first convex portion 35 and the end on the + Z′-axis side of the effective vibration region 359 are included. Coincides with the Y′-axis direction. Similarly, since the side surface 372 of the second convex portion 37 is a surface perpendicular to the main surface 371, the end A3 of the second convex portion 35 and the −Z′-axis side of the effective vibration region 379 are arranged. The end coincides with the Y′-axis direction. Therefore, by using the ends A1 and A3 as a reference, that is, the end A1 is formed to overlap the side surface 373 of the second convex portion 37, and the end A3 is formed to overlap the side surface 353 of the first convex portion 35. Thus, the displacement of the effective vibration regions 359 and 379 can be easily and reliably suppressed. Further, since the ends A1 and A3 are portions that can be easily visually recognized as “corners” from the outside, for example, it is possible to easily inspect (observe) whether or not the positional relationship is satisfied.

In addition, the centers O2 and O3 of the effective vibration regions 359 and 379 in the Z′-axis direction are preferably positioned so as to overlap the center O1 and the Y′-axis direction of the quartz substrate 3 in the Z′-axis direction, respectively. Thereby, since the vibration part 31 can be formed in the center part of the Z'-axis direction of the quartz substrate 3, the vibration part 31 can be vibrated with sufficient balance, and the vibration characteristic of the vibration piece 2 can be improved. .
Moreover, although the height t1 of the 1st convex part 35 and the height t2 of the 2nd convex part 37 may differ, it is preferable that it is the same. Thereby, since the vibration part 31 can be vibrated with sufficient balance, the vibration characteristic of the resonator element 2 can be further improved.

2. Next, a method for manufacturing the resonator element 2 (a manufacturing method of the present invention) will be described with reference to FIGS. 5 and 6.
The manufacturing method of the resonator element 2 includes a first step of preparing an AT-cut quartz substrate 30, a second step of forming a vibrating portion 31 and a thin portion 32 on the quartz substrate 30 to obtain the quartz substrate 3, and a quartz substrate 3 has a third step of forming the conductor pattern 4. In the second step, the first mask M1 corresponding to the first convex portion 35 is formed on the main surface of the quartz substrate 30 on the + Y′-axis side, and the second convex portion 37 is formed on the main surface on the −Y′-axis side. A mask forming process for forming a second mask M2 corresponding to the above, and an etching process for etching the quartz crystal substrate 30 through the first mask M1 and the second mask M2.

Hereinafter, each of these steps will be described in detail.
[First step]
First, as shown in FIG. 5A, a plate-like quartz substrate 30 cut out by AT cut is prepared. The quartz substrate 30 is a member that becomes the quartz substrate 3 through processing described later.
[Second step]
(Mask formation process)
First, as shown in FIG. 5B, the first mask M1 is formed on the upper surface of the quartz substrate 30 and the second mask M2 is formed on the lower surface by using a photolithography method or the like. The first mask M1 is formed corresponding to the first convex portion 35, and the second mask M2 is formed corresponding to the second convex portion 37. The first mask M1 and the second mask M2 have the same shape (including size).

Further, as shown in FIG. 5B, the first mask M1 and the second mask M2 are displaced in the Z′-axis direction. Specifically, the first and second masks M1 and M2 are formed so that the first mask M1 is positioned on the + Z ′ axis side with respect to the second mask M2.
Further, the first mask M1 is formed such that the center O2 in the Z′-axis direction is positioned on the + Z′-axis side with respect to the center O1 in the Z′-axis direction of the quartz substrate 30, and the second mask M2 The center O3 in the Z′-axis direction is formed so as to be located on the −Z′-axis side with respect to the center O1. Further, the separation distance D1 between the center O1 and the center O2 is substantially equal to the separation distance D2 between the center O1 and the center O3.

The amount of displacement in the Z′-axis direction of the first and second masks M1 and M2 (that is, the separation distance D3 between the centers O2 and O3) is not particularly limited as long as the above-described quartz substrate 3 can be manufactured. The sum of the height t1 of the first convex portion 35 to be formed and the height t2 (t2 = t1) of the second convex portion 37 is t, and the etching rate (etching depth per unit time) of the quartz substrate 30 in the Y′-axis direction ) Is EL _{Y ′} , the etching rate in the Z′-axis direction is EL _{Z ′,} and the length of the side surfaces 353 and 373 in the Z′-axis direction is L3, (ELz _′ / ELy _′ ) × t / 2 ≦ D3 ≦ (ELz _′ / ELy _′ ) × t / 2 + L3 is preferably satisfied. Note that L3 can be easily obtained from the inclination θ of the side surfaces 353 and 373 with respect to the Y ′ axis and the value of t (t / 2).

(Etching process)
Next, the quartz crystal substrate 30 is etched through the first and second masks M1 and M2. An etching method is not particularly limited, and a wet etching method can be used. Thereby, as shown in FIG. 5C, the quartz substrate 3 having the vibration part 31 having the first protrusion 35 and the second protrusion 37 and the thin part 32 formed around the vibration part 31 is obtained. can get.

  The side surface 352 of the first convex portion 35 is eroded inward (−Z′-axis side) from the + Z′-axis side end of the first mask M1 by side-etching the crystal substrate 30 in the −Z′-axis direction. Formed in position. Further, the side surface 352 appears as a vertical surface substantially perpendicular to the main surface 351 of the first convex portion 35. On the other hand, the side surface 353 of the first protrusion 35 appears as an inclined surface inclined toward the −Z′-axis side from the −Z′-axis side end of the first mask M <b> 1.

  Similarly, the side surface 372 of the second convex portion 37 is moved inward (+ Z′-axis side) from the −Z′-axis side end of the second mask M2 by side-etching the crystal substrate 30 in the + Z′-axis direction. It is formed at the eroded position. Further, the side surface 372 appears as a vertical surface substantially perpendicular to the main surface 371 of the second convex portion 37. On the other hand, the side surface 373 of the second convex portion 37 appears as an inclined surface inclined toward the + Z′-axis side from the + Z′-axis side end of the second mask M2.

The end A1 of the main surface 351 of the first convex portion 35 is positioned so as to overlap the side surface 373 of the second convex portion 37 in the Y′-axis direction. In other words, the end A1 is located between the ends A4 and B4 in the Z′-axis direction. Further, the end A3 of the main surface 371 of the second convex portion 37 is positioned so as to overlap the side surface 353 of the first convex portion 35 in the Y′-axis direction. In other words, the end A3 is located between the ends A2 and B2 in the Z′-axis direction.
Further, the end A3 is located away from the end A1 on the −Z ′ axis side. Further, the end A1 is located on the + Z′-axis side with respect to the center O1 of the quartz substrate 30 (quartz substrate 3), and the end A3 is located on the −Z′-axis side with respect to the center O1.

[Third step]
After the removal of the first and second masks M1 and M2, as shown in FIG. 6, the conductor pattern 4 (first and second excitation electrodes 411 and 412, first and second connection electrodes 421, 422 and first and second connection wirings 431 and 432) are formed. Specifically, for example, the conductive pattern 4 is a quartz substrate using, for example, Cr (chromium) and Au (gold) in this order by vapor deposition such as vapor deposition, sputtering, ion plating, PVD, and CVD. 3 is formed, and then a mask corresponding to the conductor pattern 4 is formed on the film using a photolithography method or the like, and the film is patterned using a dry etching method or the like, and then the mask is removed. can do.
Through the above steps, the resonator element 2 is obtained.

In particular, in the above-described manufacturing method, the shift amount D3 between the first and second masks M1 and M2 is (EL _{Y ′} / EL _{Z ′} ) × t / 2 ≦ D3 ≦ {(EL _{Y ′} / EL _{Z ′} ) × Since the relationship t / 2} + L3 is satisfied, the end A1 of the main surface 351 of the first convex portion 35 is surely positioned so as to overlap the side surface 373 of the second convex portion 37 in the Y′-axis direction. The end A3 of the main surface 371 of the second convex portion 37 can be positioned so as to overlap the side surface 353 of the first convex portion 35 in the Y′-axis direction.

  In the manufacturing method described above, the center O2 of the first mask M1 is formed so as to be positioned on the + Z ′ axis side with respect to the center O1 of the quartz substrate 30, and the center O3 of the second mask M2 is with respect to the center O1. Since it is formed so as to be located on the −Z′-axis side, the vibrating portion 31 (first and second convex portions 35 and 37) can be formed in the center portion of the quartz substrate 3 in the Z′-axis direction. Therefore, the vibration part 31 can be vibrated with good balance.

Second Embodiment
Next, a second embodiment of the vibrator of the invention will be described.
FIG. 7 is a cross-sectional view of a vibrator according to the second embodiment of the present invention.
Hereinafter, the vibrator of the second embodiment will be described focusing on the differences from the first embodiment described above, and description of similar matters will be omitted.

The vibrator according to the second embodiment of the present invention is the same as that of the first embodiment described above except that the configuration of the package is different. In addition, the same code | symbol is attached | subjected to the structure similar to 1st Embodiment mentioned above.
As shown in FIG. 7, the package 9 </ b> A includes a plate-like (flat plate-like) base 91 </ b> A and a cap-like lid 92 </ b> A having a recess 921 that opens to the lower surface. In such a package 9A, the opening of the recess 921 is closed by the base 91A to form a storage space S, and the resonator element 2 is stored in the storage space S in an airtight manner.
Also according to the second embodiment, the same effects as those of the first embodiment described above can be exhibited.

<Third Embodiment>
Next, a third embodiment of the vibrator of the invention will be described.
FIG. 8 is a cross-sectional view of a vibrator according to the third embodiment of the present invention.
Hereinafter, the resonator according to the third embodiment will be described focusing on the differences from the first embodiment described above, and description of similar matters will be omitted.

The vibrator according to the third embodiment of the present invention is the same as that of the first embodiment described above except that the configuration of the package is different except that the vibrator further includes an electronic component. In addition, the same code | symbol is attached | subjected to the structure similar to 1st Embodiment mentioned above.
As shown in FIG. 8, the vibrator 1 according to the present embodiment includes a vibrating piece 2, a package 9 that houses the vibrating piece 2, and a temperature-sensitive component (electronic component) 6 that detects the temperature of the vibrating piece 2. doing.

Further, the package 9 has a storage portion 991 for storing the temperature sensitive component 6. The storage part 991 can be formed, for example, by providing a frame-like member 99 on the bottom surface side of the base 91.
As the temperature-sensitive component 6, for example, a thermistor whose physical quantity, for example, electric resistance changes according to a temperature change can be used. The electric resistance of the thermistor can be detected by an external circuit, and the detected temperature of the thermistor can be measured.
Also according to the third embodiment, the same effects as those of the first embodiment described above can be exhibited.

  The vibration piece and the vibrator of the present invention have been described above. In the above-described vibrator, the configuration in which only the resonator element is stored in the storage space S has been described. However, other electronic components may be stored in the storage space S. Examples of such an electronic component include a temperature detection element such as a thermistor that detects the temperature of the vibration piece, and an IC chip 8 that will be described later that controls driving of the vibration piece 2.

(Oscillator)
Next, an oscillator to which the resonator element according to the invention is applied (the oscillator according to the invention) will be described.
An oscillator 10 shown in FIG. 9 includes a vibrator 1 and an IC chip (chip component) 8 for driving the resonator element 2. Hereinafter, the oscillator 10 will be described with a focus on differences from the above-described vibrator, and description of similar matters will be omitted.

The package 9 includes a box-shaped base 91 having a recess 911 and a plate-shaped lid 92 that closes the opening of the recess 911.
The concave portion 911 of the base 91 opens to the first concave portion 911a that opens to the upper surface of the base 91, the second concave portion 911b that opens to the central portion of the bottom surface of the first concave portion 911a, and the central portion of the bottom surface of the second concave portion 911b. And a third recess 911c.

A first connection terminal 95 and a second connection terminal 96 are formed on the bottom surface of the first recess 911a. Further, the IC chip 8 is disposed on the bottom surface of the third recess 911c. The IC chip 8 has a drive circuit (oscillation circuit) for controlling the drive of the resonator element 2. When the resonator element 2 is driven by the IC chip 8, a signal having a predetermined frequency can be taken out.
In addition, a plurality of internal terminals 93 that are electrically connected to the IC chip 8 through wires are formed on the bottom surface of the second recess 911b. The plurality of internal terminals 93 include terminals electrically connected to external terminals (mounting terminals) 94 formed on the bottom surface of the package 9 via vias (not shown) formed on the base 91, vias (not shown), A terminal electrically connected to the first connection terminal 95 via a wire and a terminal electrically connected to the second connection terminal 95 via a via or a wire (not shown) are included.
In the configuration of FIG. 9, the configuration in which the IC chip 8 is arranged in the storage space S has been described. However, the arrangement of the IC chip 8 is not particularly limited, and for example, the outside of the package 9 (the bottom surface of the base). May be arranged.

(Electronics)
Next, an electronic device to which the resonator element according to the invention is applied (electronic device according to the invention) will be described in detail with reference to FIGS.
FIG. 10 is a perspective view illustrating a configuration of a mobile (or notebook) personal computer to which an electronic device including the resonator element according to the invention is applied. In this figure, a personal computer 1100 includes a main body portion 1104 provided with a keyboard 1102 and a display unit 1106 provided with a display portion 100. The display unit 1106 is rotated with respect to the main body portion 1104 via a hinge structure portion. It is supported movably. Such a personal computer 1100 has a built-in vibrator 1 that functions as a filter, a resonator, a reference clock, and the like.

  FIG. 11 is a perspective view illustrating a configuration of a mobile phone (including PHS) to which an electronic device including the resonator element according to the invention is applied. In this figure, a cellular phone 1200 includes a plurality of operation buttons 1202, an earpiece 1204, and a mouthpiece 1206, and the display unit 100 is disposed between the operation buttons 1202 and the earpiece 1204. Such a cellular phone 1200 incorporates the vibrator 1 that functions as a filter, a resonator, and the like.

  FIG. 12 is a perspective view illustrating a configuration of a digital still camera to which an electronic device including the resonator element according to the invention is applied. In this figure, connection with an external device is also simply shown. Here, an ordinary camera sensitizes a silver halide photographic film with a light image of a subject, whereas a digital still camera 1300 photoelectrically converts a light image of a subject with an imaging device such as a CCD (Charge Coupled Device). An imaging signal (image signal) is generated.

  A display unit is provided on the back of a case (body) 1302 in the digital still camera 1300, and is configured to perform display based on an imaging signal from the CCD. The display unit is a finder that displays an object as an electronic image. Function. A light receiving unit 1304 including an optical lens (imaging optical system), a CCD, and the like is provided on the front side (the back side in the drawing) of the case 1302.

  When the photographer confirms the subject image displayed on the display unit and presses the shutter button 1306, the CCD image pickup signal at that time is transferred and stored in the memory 1308. In the digital still camera 1300, a video signal output terminal 1312 and an input / output terminal 1314 for data communication are provided on the side surface of the case 1302. As shown in the figure, a television monitor 1430 is connected to the video signal output terminal 1312 and a personal computer 1440 is connected to the input / output terminal 1314 for data communication as necessary. Further, the imaging signal stored in the memory 1308 is output to the television monitor 1430 or the personal computer 1440 by a predetermined operation. Such a digital still camera 1300 incorporates a vibrator 1 that functions as a filter, a resonator, or the like.

In addition to the personal computer shown in FIG. 10 (mobile personal computer), the cellular phone shown in FIG. 11, and the digital still camera shown in FIG. Inkjet printers), laptop personal computers, televisions, video cameras, video tape recorders, car navigation devices, pagers, electronic notebooks (including those with communication functions), electronic dictionaries, calculators, electronic game devices, word processors, workstations, televisions Telephone, crime prevention TV monitor, electronic binoculars, POS terminal, medical equipment (for example, electronic thermometer, blood pressure monitor, blood glucose meter, electrocardiogram measuring device, ultrasonic diagnostic device, electronic endoscope), fish detector, various measuring devices, instruments Type (eg car , Aircraft, gauges of a ship), can be applied to a flight simulator or the like.
As described above, the resonator element, the vibrator manufacturing method, the oscillator, and the electronic device of the present invention have been described based on the illustrated embodiment. However, the present invention is not limited to this, and the configuration of each part is the same. It can be replaced with any configuration having the above function. In addition, any other component may be added to the present invention. Moreover, you may combine each embodiment suitably.

  DESCRIPTION OF SYMBOLS 1 ... Vibrator 10 ... Oscillator 2 ... Vibrating piece 3, 30 ... Quartz substrate 31 ... Vibrating part 32 ... Thin part 35 ... First convex part 351 ... Main surface 352 ... Side 353 ... Side surface 359 ... Effective vibration region 37 ... Second convex portion 371 ... Main surface 372 ... Side surface 373 ... Side surface 379 ... Effective vibration region 4 ... Conductor pattern 411 ... First excitation electrode 412 ... Second Excitation electrode 421 ... 1st connection electrode 422 ... 2nd connection electrode 431 ... 1st connection wiring 432 ... 2nd connection wiring 51 ... 1st convex part 512 ... Side 52 ... 2nd convex part 522 ... ... Side 6 ... Temperature sensitive parts 71,72 ... Conductive fixing member 8 ... IC chip 9, 9A ... Package 91, 91A ... Base 911 ... Recess 911a ... First recess 911b ... Second recess 911c 3rd recessed part 92, 92A ... Lid 921 ... Recessed 93 ... Internal terminal 99 ... Member 991 ... Storage part 94 ... External terminal 95 ... 1st connecting terminal 96 ... 2nd connecting terminal 100 ... ... Display unit 1100 ... Personal computer 1102 ... Keyboard 1104 ... Main unit 1106 ... Display unit 1200 ... Mobile phone 1202 ... Operation buttons 1204 ... Earpiece 1206 ... Mouthpiece 1300 ... Digital still camera 1302 …… Case 1304 …… Light receiving unit 1306 …… Shutter button 1308 …… Memory 1312 …… Video signal output terminal 1314 …… Input / output terminal 1430 …… TV monitor 1440 …… Personal computer A1, A2, A3, A4, B2, B4 ... end O1, O2 O3 ... Center M1, M1 '... 1st mask M2, M2' ... 2nd mask D1, D2, D3 ... Separation distance F1, F2 ... Plane t1, t2 ... Height θ1, θ2, θ3, θ4 ... angle

Claims (10)

A vibrating portion including a first convex portion projecting on one main surface side of the substrate and a second convex portion projecting on the other main surface side on the back surface side with respect to one main surface side of the substrate; A substrate including a thin portion disposed along an outer edge of the vibration portion and having a thickness smaller than the thickness of the vibration portion,
The first convex portion is inclined with respect to the main surface of the first convex portion, faces the first side surface in a predetermined direction, and is perpendicular to the main surface of the first convex portion. A second side which is
The second convex portion has a third side surface perpendicular to the main surface of the second convex portion, and faces the third side surface in the predetermined direction, and is inclined with respect to the main surface of the first convex portion. A fourth side surface,
The second side surface is disposed so as to overlap the fourth side surface in plan view in the thickness direction of the substrate,
The resonator element, wherein the third side surface is disposed so as to overlap the first side surface in a plan view in the thickness direction of the substrate. A vibration part including a first convex part protruding to the + Y′-axis side and a second convex part protruding to the −Y′-axis side, and a thickness greater than the thickness of the vibration part arranged along the outer edge of the vibration part A rotating Y-cut quartz substrate including a thin-walled portion,
Including a conductor pattern disposed on the quartz substrate,
An end on the + Z′-axis side of the main surface of the first convex portion is arranged so as to overlap with a side surface located on the + Z′-axis side of the main surface of the second convex portion in a plan view in the Y′-axis direction. And
An end on the −Z′-axis side of the main surface of the second convex portion overlaps with a side surface located on the −Z′-axis side of the main surface of the first convex portion in a plan view in the Y′-axis direction. Vibrating piece characterized by being arranged in. In claim 2,
The angle formed between the side surface on the −Z′-axis side of the first convex portion and the main surface of the first convex portion is the side surface on the + Z′-axis side of the first convex portion and the main surface of the first convex portion. Smaller than the angle formed by
The angle formed between the side surface on the + Z′-axis side of the second convex portion and the main surface of the second convex portion is the side surface on the −Z′-axis side of the second convex portion and the main surface of the second convex portion. An oscillating piece characterized by being smaller than the angle formed by. In claim 3,
The side surface on the + Z′-axis side of the first convex portion is perpendicular to the main surface of the first convex portion,
The resonator element according to claim 1, wherein a side surface on the −Z′-axis side of the second convex portion is perpendicular to a main surface of the second convex portion. In any one of Claims 2 thru | or 4,
An end on the + Z′-axis side of the main surface of the first convex portion is an end on the + Z′-axis side of the second convex portion that intersects a plane that bisects the thickness of the second convex portion, and a Y′-axis Arranged so as to overlap in plan view in the direction,
An end on the −Z′-axis side of the main surface of the second convex portion is an end on the −Z′-axis side of the first convex portion that intersects a plane that bisects the thickness of the first convex portion, and Y 'The resonator element is arranged so as to overlap in a plan view in the axial direction. In any one of claims 2 to 5,
The resonator element according to claim 1, wherein the quartz substrate is an AT cut quartz substrate. A resonator element according to any one of claims 1 to 6,
And a package in which the resonator element is accommodated. A resonator element according to any one of claims 1 to 6,
An oscillator comprising: an oscillation circuit electrically connected to the resonator element.   An electronic device comprising the resonator element according to claim 1. Preparing a rotating Y-cut quartz substrate;
A first mask is disposed on the main surface on the + Y′-axis side of the quartz substrate, and the first mask is disposed on the main surface on the −Y′-axis side so as to be shifted to the −Z′-axis side with respect to the first mask. By arranging two masks and etching the quartz substrate exposed from the first mask and the second mask, a first convex portion protruding to the + Y′-axis side and a −Y′-axis are formed on the quartz substrate. Forming a mesa substrate including a vibrating portion including a second convex portion protruding to the side, and a thin portion having a thickness smaller than the thickness of the vibrating portion disposed along an outer edge of the vibrating portion;
And a step of forming a conductor pattern on the mesa substrate.

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