JP2013141312A - Inspection method of piezoelectric vibrator and piezoelectric vibrator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an inspection method of a piezoelectric vibrator which realizes accurate inspection of the mounting state of the piezoelectric vibrator, mounted on a package base, in a height direction.SOLUTION: In an inspection method of a piezoelectric vibrator for achieving the above object, a resistance value between a metal pattern for inspection 20, which is formed at a conductive lid 38 forming a package 40 of the piezoelectric vibrator 10 and/or at a package base 12, and a metal pattern formed at a piezoelectric vibration piece 24 (one metal pattern 32a, the other metal pattern 32b) or capacitor capacitance C0 between the metal pattern for the inspection 20 and the other metal pattern 32b is measured to determine the quality of the piezoelectric vibrator 10.

Description

  The present invention relates to a piezoelectric vibrator inspection method and a piezoelectric vibrator, and particularly suitable for inspecting whether or not the mounting angle and height of a piezoelectric vibrating piece with respect to a package base are appropriate. The present invention relates to a method and a piezoelectric vibrator.

  As an inspection in the process of manufacturing the piezoelectric vibrator, there is a determination as to whether the piezoelectric vibrating piece is mounted on the package base. As a method for inspecting the mounting state of such a piezoelectric vibrating piece, a determination method based on image recognition is known. For example, Patent Document 1 discloses that the position and amount of the conductive adhesive for mounting the piezoelectric vibrating piece, the displacement of the rotation angle between the package and the piezoelectric vibrating piece, and the like are detected by image recognition, and correction is performed. Has been.

  Patent Document 2 discloses that a piezoelectric vibrating piece mounted on a package base is imaged to detect the presence or absence of breakage such as displacement in the X-axis and Y-axis directions, displacement in the rotation angle, and cracks and chips. ing.

Japanese Patent Laid-Open No. 2005-210608 JP 2004-15792 A

  According to the method disclosed in the above-mentioned patent document, it is possible to surely detect a deviation on a plane. However, for example, in a piezoelectric vibrator that holds a piezoelectric vibrating piece in a cantilever state, an inclination during mounting, that is, a deviation in the height direction occurs, and depending on the amount of displacement, the tip of the piezoelectric vibrating piece may be a bottom plate of a lid or a package base May come into contact. As described above, when the piezoelectric vibrating piece comes into contact with the lid or the bottom plate of the package base, a phenomenon such as a significant change in the frequency characteristics of the piezoelectric vibrator or a defective oscillation occurs. Is done.

  Conventionally, since the high-precision inspection of the mounting state in the height direction has not been established, the safety factor is set high so that the piezoelectric vibrating reed does not contact the lid or the bottom plate of the package base. It was. For this reason, even though there is no contact with the bottom plate of the lid or package base, that is, even though it can be handled as a non-defective product, it is classified as a defective product because it exceeds the specification as a non-defective product. Has led to a decline.

  Accordingly, the present invention provides a piezoelectric vibrator inspection method capable of accurately inspecting the mounting state of the piezoelectric vibrating reed relative to the package base in the height direction, and a piezoelectric vibrator capable of realizing this inspection method. Objective.

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 Resistance between the metal pattern formed on the conductive lid and / or package base constituting the package of the piezoelectric vibrator and the metal pattern formed on the piezoelectric vibrating piece or two metals A method for inspecting a piezoelectric vibrator, comprising: measuring a capacitor capacity between patterns and performing pass / fail judgment of the piezoelectric vibrator.
According to the inspection method of the piezoelectric vibrator having such a feature, it is possible to accurately inspect the mounting state of the piezoelectric vibrating piece in the height direction with respect to the package base.

Application Example 2 In the piezoelectric vibrator inspection method according to Application Example 1, when the resistance value is measured, if the measured resistance value is higher than a predetermined reference resistance value, When it is determined as a defective product when it is less than the resistance value, and the capacitor capacity is measured, when the measured capacitor capacity is smaller than a predetermined reference capacitance value, it is a non-defective product and when it is greater than the reference capacitance value A method for inspecting a piezoelectric vibrator, characterized in that it is determined as a defective product.
According to the method for inspecting a piezoelectric vibrator having such a feature, a non-defective product and a defective product can be easily and accurately determined.

  Application Example 3 In the piezoelectric vibrator inspection method according to Application Example 1 or Application Example 2, measurement of a resistance value or measurement of a capacitor capacity between the two metal patterns constitutes the piezoelectric vibrator. A method for inspecting a piezoelectric vibrator, which is performed using an input / output terminal and a ground terminal provided outside the package.

  The insulation inspection between the input / output terminal (HOT terminal) and the ground terminal (GND terminal) is an inspection that is also performed in the conventional manufacturing process. Therefore, with such an inspection method, there is no process burden in performing the pass / fail determination inspection.

  [Application Example 4] The piezoelectric vibrator inspection method according to Application Example 1 or Application Example 2, wherein the capacitor capacitance is measured by two input / output units arranged outside a package constituting the piezoelectric vibrator. A method for inspecting a piezoelectric vibrator, which is performed using a terminal.

  Application of a voltage between the input / output terminals (HOT terminals) has been conventionally performed in the F adjustment process. For this reason, when performing an inspection by such a method, it is possible to determine whether the piezoelectric vibrator is good or bad during the F adjustment process.

Application Example 5 A piezoelectric vibrator including a package composed of a package base and a lid, and a piezoelectric vibrating piece accommodated in the package, wherein one end of the piezoelectric vibrating piece is made of a conductive adhesive. In a cantilevered piezoelectric vibrator fixed to the base and having the other end as a free end, the lid constituting the package is made conductive and has a conduction path between the package base and a ground terminal. Forming a metal pattern electrically connected to an excitation electrode at the free end of the piezoelectric vibrating piece, and providing a metal pattern for position inspection facing the free end of the piezoelectric vibrating piece on the package base, The piezoelectric vibrator according to claim 1, wherein the inspection metal pattern has a conduction path between the inspection metal pattern and the ground terminal.
According to the piezoelectric vibrator having such a configuration, the above-described inspection method of the piezoelectric vibrator can be carried out.

  Application Example 6 In the piezoelectric vibrator according to Application Example 5, the metal pattern is connected to one excitation electrode formed on one main surface of the piezoelectric vibrating piece facing the lid. And the other metal pattern connected to the other excitation electrode formed on the other main surface of the piezoelectric vibrating reed facing the bottom plate of the package base, and the one metal pattern is The other metal pattern is formed on at least one of the end portions in the width direction at the free end of the piezoelectric vibrating piece, and the inspection metal pattern is formed on the other end of the piezoelectric vibrating piece. A piezoelectric vibrator formed at a position facing the metal pattern.

  By adopting such a metal pattern configuration, it is possible to reduce the area of overlapping portions of the metal patterns on the front and back surfaces (one main surface and the other main surface) of the piezoelectric element plate. For this reason, when a voltage is applied to an excitation electrode, it can suppress that a vibration is excited in the overlapping part of a metal pattern.

  Application Example 7 In the piezoelectric vibrator according to Application Example 5, the metal pattern is formed on one excitation electrode formed on one main surface of the piezoelectric vibrating piece facing the lid or on the package base. The one main surface and the other main surface at the free end edge of the piezoelectric vibrating piece connected to any one of the other excitation electrodes formed on the other main surface of the piezoelectric vibrating piece facing the bottom plate A piezoelectric vibrator characterized in that it is formed in the entire region along the width direction.

  By adopting such a configuration of the metal pattern, the voltage applied to the metal pattern on the front and back surfaces of the piezoelectric element plate becomes a conductive potential. For this reason, even if there are many overlapping portions, vibrations are not excited.

Application Example 8 A piezoelectric vibrator including a package base, a package including a lid, and a piezoelectric vibrating piece mounted on the package, wherein the package base includes a ground terminal, and the piezoelectric vibration The piece has a thin portion having an input / output electrode and a thick portion having an excitation electrode, and the package base is provided with a position inspection metal pattern facing the thick portion, and the inspection metal pattern Has a conduction path between the grounding terminal and the piezoelectric vibrator.
If it is a piezoelectric vibrator of such composition, the inspection method of a piezoelectric vibrator which has the above features can be carried out.

[Application Example 9] A piezoelectric vibrator according to Application Example 8, wherein the piezoelectric vibrating piece is of a convex type, a bevel type, or a mesa type.
When the piezoelectric vibrating piece is of a convex type, an excitation electrode is inevitably formed on the belly foot part, so that a design change to the piezoelectric vibrating piece is not required. In the case of a bevel type or a mesa type, a metal pattern may be formed at a corner that contacts the bottom plate or the like.

Application Example 10 In the piezoelectric vibrator according to Application Example 8 or Application Example 9, in addition to the ground terminal, the package base is formed on a main surface of the piezoelectric vibrating piece facing the lid. One input / output terminal electrically connected to one excitation electrode and the other input electrode electrically connected to the other excitation electrode formed on the main surface of the piezoelectric vibrating reed facing the bottom plate of the package base With input and output terminals,
A piezoelectric vibrator, wherein the inspection metal pattern is electrically connected to the one input / output terminal.
In such a configuration, the piezoelectric vibrator can be inspected in the F-tone process.

It is a figure which shows the structure of the piezoelectric vibrator which concerns on 1st Embodiment. It is a figure which shows the structure of the package base in the piezoelectric vibrator which concerns on 1st Embodiment. It is a figure which shows the structure of the piezoelectric vibrating piece in the piezoelectric vibrator which concerns on 1st Embodiment. It is a flow which shows the outline of the manufacturing process of a piezoelectric vibrator. It is a figure which shows the structure of the piezoelectric vibrating piece in the piezoelectric vibrator which concerns on 2nd Embodiment. It is a figure which shows the structure of the piezoelectric vibrator which concerns on 3rd Embodiment. It is a flow which shows the outline of the manufacturing process of a piezoelectric vibrator in the case of implementing an inspection process after a sealing process. It is a flow which shows the outline of the manufacturing process of a piezoelectric vibrator in the case of implementing an inspection process after a mounting process and before an F tone process. It is a flow which shows the outline of the manufacturing process of a piezoelectric vibrator in the case of implementing an inspection process after a F adjustment process and before a sealing process. It is a figure which shows the other structure of the package base in the piezoelectric vibrator which concerns on 3rd Embodiment. It is a schematic diagram for calculating a capacitor capacity.

Hereinafter, a piezoelectric vibrator inspection method of the present invention and a piezoelectric vibrator for carrying out this inspection method will be described in detail with reference to the drawings.
First, a first embodiment according to the piezoelectric vibrator of the present invention will be described with reference to FIGS. 1A is a diagram illustrating a planar configuration of the piezoelectric vibrator excluding the lid, and FIG. 1B is a diagram illustrating a cross section taken along the line AA in FIG. 1 (C) is a diagram showing the configuration of the back surface of the piezoelectric vibrator. 2 is an exploded view showing the structure of the package base, FIG. 2A is a view showing the planar structure of the bottom plate, and FIG. 2B is a plan view showing the structure of the seam ring. 3 is a diagram showing a configuration of the piezoelectric vibrating piece, FIG. 3A is a diagram showing a planar configuration of the piezoelectric vibrating piece, and FIG. 3B is an electrode formed on one main surface. FIG. 3C is a diagram showing a state in which the electrode pattern formed on the other main surface is viewed from a plan view direction.

The piezoelectric vibrator 10 according to the present embodiment is basically configured of a piezoelectric vibrating piece 24 and a package 40 that accommodates the piezoelectric vibrating piece 24.
The form of the piezoelectric vibrating piece 24 is not particularly limited, but the cantilever state may be selected as the mounting form. In the example shown in FIG. 1, a quartz base plate cut out at a cut angle called AT cut is selected as a base plate (piezoelectric base plate) 25 having a piezoelectric effect. Each of the two main surfaces of the piezoelectric element plate 25 (hereinafter, the main surface facing the lid 38 in the mounted state is called one main surface, and the main surface facing the bottom plate 14 of the package base 12 is called the other main surface). A pair of excitation electrodes arranged opposite to each other (hereinafter, the excitation electrode formed on one main surface is referred to as one excitation electrode 26a, and the excitation electrode formed on the other main surface is referred to as the other excitation electrode 26b). The two input / output electrodes 30a and 30b and the extraction electrodes 26a and 26b and the extraction electrodes 28a and 28b that electrically connect the input / output electrodes 30a and 30b are used as a reference.

  In the piezoelectric vibrating piece 24 according to the embodiment, in the mounted state, the one side of the width direction along the free end edge of one main surface on which one excitation electrode 26a located on the opening side of the package base 12 is formed is The metal pattern 32a is formed. One metal pattern 32a formed along the free edge is electrically connected to one excitation electrode 26a formed on the main surface. On the other hand, one of the end portions in the width direction at the free end of the other main surface on which the other excitation electrode 26b facing the bottom plate 14 of the package base 12 is formed (in the embodiment shown in FIG. The other metal pattern 32b is formed on the right side when the free end is viewed as the upper side in plan view from the surface side. By setting it as such a structure, the area which the two metal patterns 32a and 32b formed via the piezoelectric element board 25 overlap can be made small. For this reason, even when a voltage is applied to the metal patterns 32a and 32b facing each other between the two main surfaces, excitation between the metal patterns 32a and 32b due to the voltage application can be suppressed.

  The package 40 includes a package base 12 and a lid 38. The package base shown in FIGS. 1 and 2 is a ring cavity type constituted by a bottom plate 14 and a seam ring 16. A fired ceramic green sheet can be used as the bottom plate 14, and the seam ring 16 is a low melting point metal and has a coefficient of thermal expansion similar to that of the constituent members of the bottom plate 14, for example, an alloy such as Kovar. Can be adopted.

  When the package base 12 is configured, the first and second mount electrodes 18a and 18b for mounting the piezoelectric vibrating reed 24 described above are formed on one main surface of the bottom plate 14 which is located inside the cavity. The inspection metal pattern 20 is formed. The inspection metal pattern 20 is formed at a position facing the other metal pattern 32b when the piezoelectric vibrating piece 24 is mounted. By setting it as such a structure, the surface of the metal pattern 20 for a test | inspection exists in the position higher than one main surface of the baseplate 14 by the thickness. Therefore, if the horizontal position in the width direction is maintained when the piezoelectric vibrating piece 24 is mounted, the free end of the piezoelectric vibrating piece 24 comes into contact with the inspection metal pattern 20 before coming into contact with the bottom plate 14, and the other side. Even when the formation range of the metal pattern 32b is reduced, the inspection can be performed.

  In addition, four external terminals are formed on the other main surface of the bottom plate 14 which is located on the back surface of the package 40. Two of the four external terminals are a first input / output terminal (hereinafter referred to as a first HOT terminal 22a) electrically connected to the first mount electrode and the second mount electrode on one main surface. Are set as second input / output terminals (hereinafter referred to as second HOT terminals 22c), and the remaining two external terminals are set as ground terminals (GND terminals 22b and 22d). The GND terminals 22 b and 22 d are electrically connected to the inspection metal pattern 20 formed on one main surface of the bottom plate 14. The inspection metal pattern 20 is electrically connected to the GND terminals 22b and 22d using the seam ring 16 and a through hole 34 formed in the bottom plate 14 below the seam ring 16 as a conduction path. .

  With such a configuration, when the free end of the piezoelectric vibrating piece 24 mounted on the package base 12 is in contact with the bottom plate 14 of the package base 12, the second electrically connected to the other excitation electrode 26b. A short circuit occurs between the HOT terminal 22c of the first electrode and the GND terminal 22b (22d) electrically connected to the inspection metal pattern 20, and the free end of the piezoelectric vibrating piece 24 is in contact with the bottom plate 14 of the package base 12. This can be detected.

  Further, the lid 38 constituting the package 40 may be a metal lid, and its constituent member may be a kovar like the seam ring 16. The lid 38 is electrically connected to at least one of the GND terminals 22 b and 22 d formed on the bottom plate 14 through the seam ring 16. The lid 38 is electrically connected to the GND terminals 22b and 22d by using the seam ring 16 and a through hole 34 formed in the bottom plate 14 below the seam ring 16 as a conduction path.

  With this configuration, when the free end of the piezoelectric vibrating piece 24 mounted on the package base 12 is in contact with the lid 38, the first HOT terminal 22a and the lid 38 connected to one excitation electrode 26a. It is possible to detect that a short circuit has occurred with the GND terminal 22b (22d) connected to, and that the free end of the piezoelectric vibrating piece 24 is in contact with the lid 38 of the package 40.

  As a method for inspecting the piezoelectric vibrator 10 having such a feature, an insulation test is performed between the HOT terminals (first HOT terminal 22a and second HOT terminal 22c) and the GND terminals 22b and 22d. Specifically, the probe is applied to each of the second HOT terminal 22c connected to the other excitation electrode 26b and the GND terminal 22b (22d) connected to the inspection metal pattern 20 to inspect the conduction state. When the resistance value (measurement value) between the second HOT terminal 22c and the GND terminal 22b (22d) measured by this inspection is higher than a predetermined reference resistance value (for example, 500 MΩ) (measurement value> reference resistance) Value) is determined to be non-defective, assuming that the insulation state, that is, the free end of the piezoelectric vibrating piece 24 is not in contact with the bottom plate 14 of the package base 12. On the other hand, when the measured resistance value (measured value) is less than or equal to the reference resistance value (measured value ≦ reference resistance value), insulation is established between the second HOT terminal 22c and the GND terminal 22b (22d). In other words, the free end of the piezoelectric vibrating piece 24 is in contact with the bottom plate 14 of the package base 12 or may be in contact with the package base 12.

  Next, a probe is applied to each of the first HOT terminal 22a connected to one excitation electrode 26a and the GND terminals 22b and 22d connected to the lid 38 to inspect the conduction state. Similarly to the above-described inspection, this inspection also measures the resistance value between the first HOT terminal 22a and the GND terminal 22b (22d), and the measured resistance value (measured value) is higher than the reference resistance value. In (measured value> reference resistance value), it is determined that the free end of the piezoelectric vibrating piece 24 is not in contact with the lid 38 and is a non-defective product. On the other hand, when the measured resistance value (measured value) is equal to or smaller than the reference resistance value (measured value ≦ reference resistance value), the free end of the piezoelectric vibrating piece 24 is in contact with or in contact with the lid 38. It is determined that the product is defective.

  FIG. 4 shows an outline of the manufacturing process of the piezoelectric vibrator 10 as described above. First, the conductive adhesive 36 is applied to the mount electrodes (the first mount electrode 18a and the second mount electrode 18b) of the package base 12. Next, the piezoelectric vibrating piece 24 is mounted via the conductive adhesive 36, and the conductive adhesive 36 is cured (mounting process). After the conductive adhesive 36 is cured, frequency adjustment (fine adjustment) of the piezoelectric vibrator is performed (F adjustment process). After the frequency adjustment is completed, the opening of the package base 12 is sealed with the lid 38 (sealing process). After the package 40 is sealed, the above-described inspection is performed on the piezoelectric vibrator 10 (inspection process). Note that the piezoelectric vibrator 10 determined as a non-defective product as a result of the inspection is carried out as a product, and the piezoelectric vibrator 10 determined as a defective product is discarded.

  According to the inspection method as described above, it is possible to accurately inspect the mounting state of the piezoelectric vibrating piece 24 with respect to the package base in the height direction. For this reason, it is not necessary to set the safety factor of the mounting state of the piezoelectric vibrating piece 24 high, and it is possible to reduce the number of wasteful disposal. Thus, throughput can be improved.

  In the embodiment described above, the lid 38 is made of metal. However, the constituent member of the lid 38 may be soda glass or the like. When such a member is selected as a constituent member of the lid 38, an inspection metal pattern may be formed on the main surface of the lid 38 facing the cavity. When the metal pattern for inspection is formed on the main surface of the lid 38, the surface of the metal pattern for inspection is lower than the main surface of the lid 38 by the thickness. For this reason, even when the arrangement area of the one metal pattern 32a formed on the piezoelectric vibrating piece 24 is reduced, the inspection as described above can be performed. Therefore, if the formation positions of the one metal pattern 32a and the other metal pattern 32b have a line-symmetric relationship with respect to the width direction, it is possible to eliminate the overlapping portion between them, and there is no possibility of excitation due to the applied voltage.

Next, a second embodiment according to the piezoelectric vibrator of the present invention capable of performing the above inspection will be described with reference to FIG.
Most of the configuration of the piezoelectric vibrator according to the second embodiment is the same as that of the piezoelectric vibrator according to the first embodiment described above. Therefore, FIG. 5 shows the structure of a piezoelectric vibrating piece, which is a difference between the piezoelectric vibrator according to the present embodiment and the piezoelectric vibrator according to the first embodiment, and FIG. 1 shows a package having the same structure. We will use it. In addition, the same code | symbol is attached | subjected to drawing and the detailed description is abbreviate | omitted to the location which makes the function the same. 5A is a plan view showing the piezoelectric vibrating piece of the piezoelectric vibrator according to the second embodiment, and FIG. 5B is formed on one main surface of the piezoelectric element plate. FIG. 5C is a diagram showing a configuration in a plan view of the pattern formed on the other main surface of the piezoelectric element plate, and FIG. 5D is a diagram at the tip portion of the piezoelectric vibrating piece. It is sectional drawing which shows the form of a metal pattern.

  The piezoelectric vibrating reed 24 of the piezoelectric vibrator 10 according to the present embodiment is configured such that the metal pattern formed at the free end is connected to only one of the one excitation electrode 26a or the other excitation electrode 26b. Specifically, as shown in FIG. 5D, one metal pattern 32a formed on one main surface is routed so as to wrap the free end of the piezoelectric element plate 25 and extends to the other main surface at the free end. Has been established. In the piezoelectric vibrating piece 24 according to the present embodiment, one metal pattern 32a extending on the other main surface is also formed along the entire width direction of the free end.

  With such a configuration, one metal pattern 32 a formed on the free end of the piezoelectric vibrating piece 24 has the same potential on the front and back surfaces of the piezoelectric element plate 25. For this reason, even when a voltage is applied to one excitation electrode 26 a and the other excitation electrode 26 b, vibration is not excited at the free end of the piezoelectric vibrating piece 24. Further, with such a configuration, even when the piezoelectric vibrating piece 24 is warped or the mounting form of the piezoelectric vibrating piece 24 is inclined, the contact of the free end of the piezoelectric vibrating piece 24 is achieved. Can be detected, and the inspection accuracy can be improved.

  Next, a third embodiment according to the piezoelectric vibrator of the present invention will be described with reference to FIG. The piezoelectric vibrator according to this embodiment is almost the same in configuration as the piezoelectric vibrator according to the first and second embodiments described above. Therefore, parts having the same function are denoted by the same reference numerals in the drawings, and detailed description thereof is omitted. 6A is a diagram illustrating a cross-sectional configuration of the piezoelectric vibrating piece, FIG. 6B is a diagram illustrating a planar configuration of the piezoelectric vibrating piece, and FIG. 6C is a diagram illustrating a bottom plate. It is a figure which shows the structure of one main surface.

  The difference between the piezoelectric vibrator 10 according to the present embodiment and the piezoelectric vibrators according to the first and second embodiments is that the form of the piezoelectric vibrating piece 24 and the inspection metal pattern 20 formed on the package base 12 are different. It is in the arrangement position.

  Specifically, in the piezoelectric vibrator 10 according to this embodiment, the piezoelectric vibrating piece 24 mounted inside the package 40 is a convex type. As shown in FIG. 6 (A), the convex-type piezoelectric vibrating piece 24 has a thick central portion in the longitudinal direction and is continuous with the thickness so that the ridge line is lowered toward the thin portions at both ends. The structure is advantageous for confining energy.

  The piezoelectric vibrating piece 10 according to the embodiment is a pair of excitation electrodes (one excitation electrode 26a and the other) formed on one main surface and the other main surface, similarly to a general convex-type piezoelectric vibrating piece 24. Excitation electrode 26b), two input / output electrodes 30a, 30b, and two input / output electrodes 30a, 30b are connected to either one excitation electrode 26a or the other excitation electrode 26b, respectively. Have.

  In the piezoelectric vibrating piece 24 having such a configuration, the package base 12 is first contacted with the package base 12 when the mounting state is deviated due to the characteristics of the form. It becomes the thick part to do. Such contact is referred to as so-called stomach slipping, and may damage the excitation electrode (the other excitation electrode 26b) formed in the portion.

  The possibility of the occurrence of such a hungry or the actual hungry state depends on the mounting height and angle of the piezoelectric vibrating reed 24 with respect to the package base 12, that is, the mounting state in the height direction. By performing the piezoelectric vibrator inspection method according to the present invention, it is possible to determine whether the piezoelectric vibrator 10 is a good product or a defective product.

  In order to perform the inspection as described above, in the piezoelectric vibrator 10 according to the present embodiment, the inspection metal pattern 20 is formed on the package base 12. It is desirable that the inspection metal pattern 20 be disposed at a place where the piezoelectric vibrating piece 24 out of the mounting state may contact first. For this reason, in the piezoelectric vibrator 10 according to the present embodiment, the thickness of one main surface of the bottom plate 14 of the package base 12 on which the other excitation electrode 26b is formed when the piezoelectric vibrating piece 24 is mounted. The inspection metal pattern 20 is arranged at a position facing the part.

  If the piezoelectric vibrator 10 satisfies such conditions, the above-described inspection can be performed. However, since the thick portion (antinode) of the convex type piezoelectric vibrating piece 24 exists closer to the bottom plate 14 than the support portion formed by the conductive adhesive 36, the vibration is smaller than the free end of the flat plate type piezoelectric vibrating piece. Even so, there is a possibility of contact with the bottom plate 14.

For this reason, in the piezoelectric vibrator 10 according to the present embodiment, in addition to the presence or absence of the contact of the piezoelectric vibrating piece 24, the distance between the thick portion of the piezoelectric vibrating piece 24 and the bottom plate 14 of the package base 12 is a predetermined value or more. It is desirable to perform an inspection using the point of the above as a criterion for determining the quality of the piezoelectric vibrator 10. Therefore, in the piezoelectric vibrator 10 according to the present embodiment, the capacitor capacitance C that can be measured from the overlapping portion between the other excitation electrode 26 b of the piezoelectric vibrating piece 24 and the inspection metal pattern 20 formed on one main surface of the bottom plate 14. Based on ₀ , the quality of the piezoelectric vibrator 10 is determined.

The capacitor capacity C ₀ can be calculated based on the dielectric constant ε, the electrode area S, and the inter-electrode distance d as shown in Equation 1 (see FIG. 11).

ここで、誘電率εは、電極を構成する物質によって定まり、電極の面積Ｓは、検査用金属パターン２０と他方の励振電極２６ｂとの重複部分の面積で定まるため、他方の励振電極２６ｂよりも面積の小さい検査用金属パターン２０の面積を定めることにより求めることができる。このため、Ｃ₀を計測により取得することで、電極間距離ｄ、すなわち圧電振動片２４の肉厚部（腹）とパッケージベース１２の底板１４との距離を算出することができる。なお、コンベックス型の圧電振動片２４では、他方の励振電極２６ｂと検査用金属パターン２０とが完全な平行では無いため、電極間距離ｄや電極の面積Ｓを一義的に定めることは困難であるが、良品の範囲を満たすｄと、Ｓの平均値から良品の条件を満たすコンデンサ容量、すなわち基準容量値Ａを導き出すことができる。

Here, since the dielectric constant ε is determined by the material constituting the electrode, and the area S of the electrode is determined by the area of the overlapping portion between the inspection metal pattern 20 and the other excitation electrode 26b, the dielectric constant ε is larger than that of the other excitation electrode 26b. It can be obtained by determining the area of the inspection metal pattern 20 having a small area. For this reason, by obtaining C ₀ by measurement, the inter-electrode distance d, that is, the distance between the thick portion (antinode) of the piezoelectric vibrating piece 24 and the bottom plate 14 of the package base 12 can be calculated. In the convex-type piezoelectric vibrating piece 24, the other excitation electrode 26b and the inspection metal pattern 20 are not completely parallel, so it is difficult to uniquely determine the inter-electrode distance d and the electrode area S. However, it is possible to derive the capacitor capacity satisfying the non-defective product, that is, the reference capacity value A, from the average value of d and S satisfying the non-defective range.

As can be seen from Equation 1, if the dielectric constant ε and the electrode area S are equal, the capacitor capacity increases as the inter-electrode distance d decreases. Therefore, the capacitance of the capacitor C ₀ that is measured, in relation to the reference capacitance value A, if good, is C ₀ were more than A if C ₀ is smaller than A (C ₀ <A) (C ₀ ≧ A) can be determined as a defective product.

When performing the inspection as described above, the area of the inspection metal pattern 20 electrically connected to the GND terminals 22b and 22d needs to be determined in advance. For this reason, it is preferable to route the electrodes (the routing pattern 21) from the inspection metal pattern 20 to the GND terminals 22b and 22d by dropping into the lower layer of the bottom plate 14 through a through hole (not shown). When the inspection metal pattern 20 is routed on one main surface of the bottom plate 14, a portion where the routing pattern 21 and the other excitation electrode 26b overlap is also taken into account by the electrode area S. This is because the measurement error of C ₀ becomes large.

  Here, the inspection of the piezoelectric vibrators according to the first and second embodiments described above is performed by inspecting whether or not the free end of the mounted piezoelectric vibrating piece 24 is in contact with the lid 38 or the bottom plate 14 of the package 40. Therefore, the inspection process could not be performed unless after the mounting process, the F adjustment process, and the sealing process. On the other hand, in the piezoelectric vibrator 10 according to the present embodiment, the inspection target is the belly of the piezoelectric vibrating piece 24. Therefore, the inspection process can be performed any time after the piezoelectric vibrating piece 24 is mounted, that is, after the mounting process. Can be done.

  Specifically, as shown in FIG. 7, the inspection process may be performed after the sealing process is completed, or as shown in FIG. 8, the inspection process is performed after the mounting process, and then the F adjustment is performed. You may make it perform a process. As shown in FIG. 8, when an inspection process is performed after the mounting process, it is possible to eliminate a defective product causing a stomach rash before the F adjustment process. It can be omitted.

  In addition, as shown in FIG. 9, the inspection process may be performed after the F adjustment process and before the sealing process. Even in such a case, it is possible to eliminate waste such as sealing by bonding a lid to a defective product.

  In addition, after the package 40 is sealed and the piezoelectric vibrator 10 is configured, an inspection process is required regardless of whether or not the above-described inspection for belly is performed. For this reason, it can be said that the flow shown in FIG. 7 which performs the test | inspection which measures a capacitor capacity simultaneously in the said test | inspection process has few process losses.

In the above embodiment, the inspection metal pattern 20 is described as being electrically connected to the GND terminals 22b and 22d. However, in the piezoelectric vibrator 10 according to the third embodiment, since the inspection target is the presence or absence of the bellows of the piezoelectric vibrating piece 24, the second HOT terminal 22c is the only HOT terminal used for the inspection. Therefore, in the piezoelectric vibrator 10 according to the third embodiment, the inspection metal pattern 20 may be connected to the first HOT terminal 22a. In such a configuration, the capacitor capacitance C ₀ between the inspection metal pattern 20 and the other excitation electrode 26b is measured between the first HOT terminal 22a and the second HOT terminal 22c. It becomes possible. In addition, when it is set as such a structure, it becomes possible to implement an inspection process in F adjustment process.

In the above-described embodiment, only the convex-type piezoelectric vibrating piece is listed as the piezoelectric vibrating piece to be stomach-trimmed. However, various piezoelectric vibrating pieces having a thick portion and a thin portion, such as a bevel-type piezoelectric vibrating piece and a mesa-type piezoelectric vibrating piece, can be included as a piezoelectric vibrating piece to be a stomach run. Here, in a piezoelectric vibrating piece having a step or a corner between a thick portion and a thin portion, such as a mesa type or a bevel type, the corner portion comes into contact with the bottom plate of the package base. Therefore, when mounting such a piezoelectric vibrating piece, a metal pattern is formed at the corner of the thick part located on the free end side on the other main surface, and this is connected to the other excitation electrode. Just do it.
The method for inspecting a piezoelectric vibrator according to the present invention can also be applied to a piezoelectric vibrator in which a tuning fork type piezoelectric vibrating piece or a SAW element piece is mounted in a cantilever manner.

  10 ......... Piezoelectric vibrator, 12 ......... Package base, 14 ......... Bottom plate, 16 ......... Seam ring, 18a, 18b ......... Mount electrode, 20 ......... Metal pattern for inspection, 22a ......... First HOT terminal, 22b ......... GND terminal, 22c ......... Second HOT terminal, 22d ......... GND terminal, 24 ......... piezoelectric vibrating piece, 25 ......... piezoelectric element plate, 26a ......... One excitation electrode, 26b .... the other excitation electrode, 28a, 28bb .... the extraction electrode, 30a, 30b .... the input / output electrode, 32a .... one metal pattern, 32b .... the other metal pattern. , 34... Through hole, 36... Conductive adhesive, 38... Lid, 40.

Claims (10)

Resistance between the metal pattern formed on the conductive lid and / or package base constituting the package of the piezoelectric vibrator and the metal pattern formed on the piezoelectric vibrating piece or the capacitor capacity between the two metal patterns Measure
A method for inspecting a piezoelectric vibrator, wherein the quality of the piezoelectric vibrator is judged. An inspection method for a piezoelectric vibrator according to claim 1,
When measuring the resistance value, if the measured resistance value is higher than a predetermined reference resistance value, it is determined as a non-defective product when it is less than the reference resistance value,
When the capacitor capacity is measured, the piezoelectric vibrator is determined as a non-defective product when the measured capacitor capacity is smaller than a predetermined reference capacitance value, and as a defective product when it is equal to or greater than the reference capacitance value Inspection method. A method for inspecting a piezoelectric vibrator according to claim 1 or 2,
The measurement of the resistance value or the capacitance of the capacitor between the two metal patterns is performed using an input / output terminal and a ground terminal arranged outside the package constituting the piezoelectric vibrator. Inspection method for piezoelectric vibrators. A method for inspecting a piezoelectric vibrator according to claim 1 or 2,
A method of inspecting a piezoelectric vibrator, wherein the measurement of the capacitor capacity is performed using two input / output terminals arranged outside a package constituting the piezoelectric vibrator. A package consisting of a package base and a lid;
A piezoelectric vibrator comprising a piezoelectric vibrating piece housed in the package,
In the cantilever-supported piezoelectric vibrator in which one end of the piezoelectric vibrating piece is fixed to the package base with a conductive adhesive and the other end is a free end,
The lid constituting the package is made conductive, and has a conduction path between the package base and a ground terminal,
Forming a metal pattern electrically connected to the excitation electrode at the free end of the piezoelectric vibrating piece;
The package base is provided with a position inspection metal pattern facing the free end of the piezoelectric vibrating piece, and the inspection metal pattern has a conduction path between the grounding terminal and the piezoelectric vibrator. . The piezoelectric vibrator according to claim 5,
The metal pattern includes: one metal pattern connected to one excitation electrode formed on one main surface of the piezoelectric vibrating piece facing the lid; and the piezoelectric vibrating piece facing the bottom plate of the package base. The other metal pattern connected to the other excitation electrode formed on the other main surface,
The one metal pattern is formed over the entire area along the free edge of the piezoelectric vibrating piece,
The other metal pattern is formed on at least one of the end portions in the width direction at the free end of the piezoelectric vibrating piece,
The piezoelectric vibrator according to claim 1, wherein the inspection metal pattern is formed at a position facing the other metal pattern. The piezoelectric vibrator according to claim 5,
The metal pattern is formed on one main surface of the piezoelectric vibrating piece facing the lid, or on the other main surface of the piezoelectric vibrating piece facing the bottom plate of the package base. Connected to one of the excitation electrodes of
A piezoelectric vibrator characterized in that it is formed over the entire area along the width direction of the one main surface and the other main surface at the free end edge of the piezoelectric vibrating piece. A package consisting of a package base and a lid;
A piezoelectric vibrator having a piezoelectric vibrating piece mounted on the package,
The package base has a ground terminal;
The piezoelectric vibrating piece has a thin portion having an input / output electrode and a thick portion having an excitation electrode,
The package base is provided with a metal pattern for position inspection that faces the thick portion, and the metal pattern for inspection has a conduction path between the metal pattern and the ground terminal. The piezoelectric vibrator according to claim 8, wherein
A piezoelectric vibrator characterized in that the piezoelectric vibrating piece is of a convex type, a bevel type, or a mesa type. The piezoelectric vibrator according to claim 8 or 9, wherein
In addition to the ground terminal, the package base has one input / output terminal electrically connected to one excitation electrode formed on the main surface of the piezoelectric vibrating piece facing the lid, and the package base A second input / output terminal electrically connected to the other excitation electrode formed on the main surface of the piezoelectric vibrating reed facing the bottom plate;
A piezoelectric vibrator, wherein the inspection metal pattern is electrically connected to the one input / output terminal.

Images