JP2011097457A - Method of manufacturing piezoelectric device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of manufacturing a piezoelectric device which removes insulation failure between the electrodes of the piezoelectric device with a simple process. <P>SOLUTION: The method of manufacturing a piezoelectric device includes a process (ST1) to form a plurality of quartz oscillators of a predetermined shape on a quartz wafer, an electrode formation process (ST2) which forms a plurality of electrodes on a quartz oscillator piece, a leakage amount measuring process (ST3) which measures the leakage amount of the quartz oscillator piece in which each electrode is formed, an electrode processing process (ST4) to process the electrode into a predetermined shape based on the measuring result of the leakage amount measuring process, an etching process (ST5) which processes the quartz oscillator making the electrode processed in the electrode processing process as a mask, and a voltage application process (ST6) which applies a predetermined voltage between each electrode and burns off the part of insulation failure by heat generation by a current. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a method for manufacturing a piezoelectric device such as a crystal resonator.

  In many cases, a piezoelectric device such as a quartz crystal resonator in which an electrode is formed on a piezoelectric element is manufactured using a photolithography technique. Moreover, in order to form a piezoelectric element having a complicated shape, it is necessary to repeatedly perform an etching process or the like. However, when etching is performed after forming an electrode on the piezoelectric element, peeling of the electrode may occur due to side etching.

  This peeled electrode becomes a belt-like shape and adheres to other electrodes, causing a short-circuit between electrodes (insulation failure). In order to remove the electrode peeled in this way, a method of removing the electrode at the peeled portion by etching has been proposed (for example, see Patent Document 1).

JP 2006-129096 A (Page 5, FIGS. 1 and 2)

  However, in the above-described conventional technology, there is a problem that the process becomes complicated by applying and etching a resist in order to remove the electrode at the peeled off portion. In particular, in order to manufacture a piezoelectric device having a complicated shape that requires multiple etching steps, the number of steps becomes enormous.

  In addition to the peeled electrodes, short-circuiting between electrodes occurs at a certain rate due to adhesion of small dust during electrode film generation, etc., but the method of removing electrodes by etching removes such inter-electrode shorts. I can't do it.

  Accordingly, an object of the present invention is to solve the above-described problems and to provide a method for manufacturing a piezoelectric device that can remove an insulation failure between electrodes of the piezoelectric device by a simple process.

  In order to solve the above-described problems and achieve the object, the piezoelectric device manufacturing method of the present invention employs the following configuration.

  The method for manufacturing a piezoelectric device according to the present invention includes an electrode forming step of forming a plurality of electrodes on a piezoelectric vibrating piece, a voltage applying step of applying a predetermined voltage between the electrodes, and burning off a defective portion by heat generation due to current. It is characterized by providing.

  In addition, the piezoelectric device manufacturing method of the present invention includes an electrode forming step of forming a plurality of electrodes on the piezoelectric vibrating piece, an etching step of etching the piezoelectric vibrating piece on which each electrode is formed, and a predetermined gap between the electrodes. And a voltage applying step of burning out the defective portion of the insulation by heat generation.

Furthermore, in addition to the above-described configuration, the piezoelectric device manufacturing method of the present invention is characterized in that, in the etching step, the piezoelectric vibrating reed is etched using each electrode as a mask to adjust the balance of the piezoelectric vibrating reed.

  Furthermore, in addition to the above-described configuration, the piezoelectric device manufacturing method of the present invention is based on a leakage amount measuring step for measuring the leakage amount of the piezoelectric vibrating piece on which each electrode is formed, and a measurement result of the leakage amount measuring step. An electrode processing step for processing the electrode into a predetermined shape, and the etching step is performed using the electrode processed in the electrode processing step as a mask.

  Furthermore, in addition to the above-described configuration, the piezoelectric device manufacturing method of the present invention is characterized in that a groove is formed in the piezoelectric vibrating piece or the frequency of the piezoelectric vibrating piece is adjusted in the etching step.

  Furthermore, in the piezoelectric device manufacturing method of the present invention, in addition to the above-described configuration, the piezoelectric vibrating piece is used for a vibration type gyro sensor, and establishes orthogonality between driving vibration and detection vibration in an etching process. Adjustment is performed.

  The piezoelectric device manufacturing method of the present invention further includes an outer shape forming step of forming a plurality of piezoelectric vibrating pieces having a predetermined shape on the piezoelectric wafer in addition to the above-described configuration, and includes an electrode forming step, an etching step, and voltage application. The process is performed on each piezoelectric vibrating piece formed on the piezoelectric wafer.

  Furthermore, the piezoelectric device manufacturing method of the present invention is characterized in that, in addition to the above-described configuration, the piezoelectric vibrating piece is a quartz crystal vibrating piece.

  According to the present invention, after etching the piezoelectric vibrating piece on which each electrode is formed, the insulation defect caused by electrode peeling due to side etching is removed by a simple process of applying a predetermined voltage between the electrodes. It becomes possible to do. Further, by performing the processing on the wafer, it becomes possible to perform processing of a large number of piezoelectric vibrating pieces at once.

It is a perspective view which shows the structure of the crystal oscillator manufactured with the manufacturing method of this embodiment. It is explanatory drawing which shows the cross-sectional shape of the crystal resonator manufactured with the manufacturing method of this embodiment, and the connection of an electrode. It is a flowchart which shows the process of the manufacturing method of this embodiment. It is explanatory drawing of the external shape formation process of a crystal oscillator. It is a perspective view showing a plurality of crystal oscillator pieces formed on a crystal wafer. It is sectional drawing of the drive leg and detection leg of a crystal oscillator. It is sectional drawing of the drive leg of a crystal oscillator. It is a top view of a crystal resonator. It is sectional drawing of the drive leg of a crystal oscillator. It is sectional drawing of a crystal oscillator drive leg. It is explanatory drawing which shows the short state between the electrodes of a crystal oscillator. It is explanatory drawing which shows the short state between the electrodes of a crystal oscillator. It is explanatory drawing of the structure for performing a voltage stamp processing process. It is explanatory drawing which shows the state which removed the insulation defect between the electrodes of a crystal oscillator.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the following description, an embodiment of the present invention will be described by taking a crystal resonator used in a vibration type gyro sensor as a piezoelectric device as an example.

[Configuration of crystal unit: Fig.1-Fig.2]
First, an example of a crystal resonator manufactured by the manufacturing method of the present invention will be described with reference to FIGS. FIG. 1 is a perspective view showing an example of the configuration of a crystal resonator 10 manufactured by the manufacturing method of the present embodiment. FIG. 2 is an explanatory view showing the cross-sectional shape of the crystal resonator 10 manufactured by the manufacturing method of the present embodiment and the connection of the electrodes. FIG. 2 shows an AA ′ cross section of FIG.

  The crystal unit 10 is configured with the X axis in the width direction, the Y ′ axis in the longitudinal direction, and the Z ′ axis in the thickness direction. Note that portions not related to the description, for example, a fixing portion to which a conductive adhesive or the like is attached when the quartz crystal unit is sealed in a sealing member such as a package are omitted.

  The crystal resonator piece 7 constituting the crystal resonator 10 is formed by being cut out from a crystal wafer by etching as will be described later. This crystal oscillator is an oscillator used as, for example, a vibration type gyro sensor. The crystal resonator element 7 is a vibration element of a tripod tuning fork type oscillator having two drive legs 11 and 12 extending from the base 14 and one detection leg 13. The crystal resonator 10 is not limited to a tripod tuning fork type, and may be a biped tuning fork type, a T type tuning fork, an H type tuning fork, or the like.

  As shown in FIG. 1, drive electrodes 20 and 21 are formed on the main plane and side surfaces of the drive legs 11 and 12, respectively. The drive electrodes 20 and 21 have an adjustment area 30. As will be described later, a part of the drive electrodes 20 and 21 is removed by laser processing in the adjustment area 30, and the drive legs 11 and 12 are re-etched in a balance adjustment process using the processed drive electrodes as a mask. It is an area. A detection electrode 22 is formed on the main plane of the detection leg 13.

  The configuration of the electrode formed on each vibration leg will be described in more detail. As shown in FIG. 2, drive electrodes 20 a and 20 b are formed on two opposing surfaces that are the main plane of the drive leg 11, and drive electrodes 21 c and 21 d are formed on the two opposing surfaces that are the main plane of the drive leg 12. ing. In addition, drive electrodes 21 a and 21 b are formed on two opposing surfaces that are the side surfaces of the drive leg 11, and drive electrodes 20 c and 20 d are formed on the two opposing surfaces that are the side surfaces of the drive leg 12.

  These drive electrodes 20a, 20b, 20c, and 20d are electrically connected to the drive electrode terminal 20, respectively. Further, the drive electrodes 21a, 21b, 21c, and 21d are also electrically connected to the drive electrode terminal 21, respectively.

  The detection leg 13 is formed with detection electrodes 22a and 22b which are paired at the corners thereof, and is connected to the detection electrode terminals 22 and 23, respectively. The GND electrode 22c on the surface facing the detection electrodes 22a and 22b is connected to the GND electrode terminal 24, and is connected to GND (0 V) of a circuit (not shown).

  When this crystal resonator 10 is used as, for example, a vibration type gyro sensor, the bending vibration in the X-axis direction shown in FIG. 1 is used as the driving vibration, and the bending vibration in the Z′-axis direction is used as the detection vibration when the angular velocity is applied. . Therefore, vibration in the Z′-axis direction does not occur when no angular velocity is applied.

  In the example shown in FIGS. 1 and 2 used in the above description, the side surfaces of the drive legs 11 and 12 and the detection leg 13 are not flat due to residues as will be described later. The shape of the residue is omitted

[Method for Manufacturing Crystal Resonator: FIGS. 3 to 12]
Next, a method for manufacturing the crystal resonator of this embodiment will be described. FIG. 3 is a flowchart showing the steps of the method for manufacturing a piezoelectric device of the present invention. Hereinafter, each process of this embodiment is demonstrated in order.

[Outline forming step: FIGS. 4 to 5]
First, the outer shape forming step (step ST1) of the manufacturing method of the present embodiment will be described. FIG. 4 is an explanatory diagram of the outer shape forming process of the crystal resonator element, and schematically shows a cross-section of the vibration leg of the crystal oscillator. FIG. 4 shows a state in which two crystal resonators 10 shown in FIG. 1 are arranged, and is a view seen from the distal direction of the drive legs 11, 12 and the detection leg 13 toward the base 14. is there.

  First, as shown in FIG. 4B, an etching solution for crystal is formed on both surfaces of the crystal wafer 1 which is a flat single crystal plate adjusted to a predetermined thickness shown in FIG. Corrosion resistant metal corrosion-resistant films 2a and 2b, and photoresists 3a and 3b are formed thereon. As the metal corrosion-resistant films 2a and 2b, a laminated film of gold (Au) and chromium (Cr) can be used.

  These metal films can be formed using a known vapor deposition technique or sputtering technique. The photoresists 3a and 3b can be formed using a known spin coating technique.

  Next, as shown in FIG. 4C, two photomasks 4a and 4b each having a transducer pattern drawn thereon are arranged above and below the crystal wafer 1, and light (arrows) is emitted from above the photomasks 4a and 4b. B) is irradiated to expose the photoresists 3a and 3b.

Next, as shown in FIG. 4D, the photoresists 3a and 3b are developed, and the metal corrosion resistant films 2a and 2b are patterned using the formed resist pattern as a mask, and an etching mask 5a which is an etching resistant mask member. 5b.
When a metal (Au) and chromium (Cr) laminated film is used as the metal corrosion resistant films 2a and 2b, each of these two metal films is etched. For example, gold (Au) is etched using a mixed solution of iodine and potassium iodide. After washing with water, chromium (Cr) is etched using a ceric ammonium nitrate solution.

Next, as shown in FIG. 4E, after removing the photoresists 3a and 3b, the quartz wafer 1 with the etching masks 5a and 5b formed on both the front and back surfaces is subjected to a hydrofluoric acid-based etching solution which is a crystal etching solution. When the substrate is immersed in the crystal, portions of the crystal not covered with the etching masks 5a and 5b are dissolved from both sides. Thereafter, by removing the etching masks 5a and 5b, the drive legs 11 and 12 and the detection legs 13 which are the vibration legs of the crystal resonator element are obtained.
As the crystal etching solution, for example, a mixed solution of hydrofluoric acid and ammonium fluoride can be used.
In the example shown in FIG. 4, only the cross section of the vibrating leg is shown, but actually, the entire outer shape of the crystal unit 10 shown in FIG. 1 is formed by this outer shape forming step (step ST 1).

FIG. 5 is a perspective view schematically showing a plurality of crystal resonator pieces 7 formed on the crystal wafer 1 by this outer shape forming process. The cutting line CC ′ will be described later.
The quartz crystal piece 7 is formed as if it was cut out from the melted portion 15 melted by etching, and each quartz crystal piece 7 is coupled to the quartz wafer 1 by a connecting portion 71. The connecting portion 71 is a portion that is cut after the balance adjustment is completed, and is a portion called a so-called folding portion.
When the connecting portion 71 is cut, the crystal resonator element 7 is separated from the crystal wafer 1 to complete the crystal oscillator 10 shown in FIG.

  FIG. 4 shows an example in which six crystal resonator pieces 7 are formed on one crystal wafer 1, but the number is not limited to the example in FIG. This is because the size and shape of the crystal resonator element 7 are selected according to the performance and characteristics of the crystal resonator to be obtained, and the size of the crystal wafer 1 is determined accordingly. Of course, if the number of crystal resonator pieces 7 formed on one crystal wafer 1 is large, a large number of crystal resonators can be manufactured at a time, so that the manufacturing cost can be reduced.

[Electrode forming step: FIG. 6]
Next, details of the electrode forming step (step ST2) of the manufacturing method of the present embodiment will be described with reference to FIG. FIG. 6 is a cross-sectional view schematically showing a cross section taken along the section line CC ′ shown in FIG. 5, and shows a cross section of the drive legs 11, 12 and the detection leg 13.

  As shown in FIG. 6B, a metal film 200 and a photoresist 300 are formed on the surfaces of the drive legs 11 and 12 and the detection leg 13 shown in FIG. In the example shown in FIG. 6B, the metal film 200 is described as a single-layer film to make the drawing easy to see. However, a laminate in which gold (Au) is provided thereon with chromium (Cr) as a base. It can be a membrane.

  The metal film 200 can be formed using a known vapor deposition technique or sputtering technique. The photoresist 300 can be formed using a known spray method, electrodeposition method, or the like.

  Next, as shown in FIG. 6C, two photomasks 400a and 400b on which the shapes of the electrodes provided on the drive legs 11 and 12 and the detection leg 13 are respectively drawn are arranged above and below the crystal wafer 1. The photoresist 300 is exposed by irradiating light (arrow B) from above the photomasks 400a and 400b. FIG. 6C shows an example of performing so-called oblique exposure in which light is irradiated obliquely.

  Next, as shown in FIG. 6D, the photoresist 300 is developed, the metal film 200 is patterned using the formed resist pattern as a mask, and the drive electrodes 20a, 20b, 20c, 20d, 21a, 21b, 21c are formed. 21d, detection electrodes 22a and 22b, and a GND electrode 22c.

[Leakage measurement process: Fig. 7]
Next, the leakage amount measuring step (step ST3) of the manufacturing method of the present embodiment will be described.
A drive signal is supplied to the drive electrode terminals 20 and 21 of the crystal unit 10 shown in FIG. 2 to vibrate the crystal unit 10.

  FIG. 7 is an example of a cross section of one drive leg 11 of the crystal resonator 10 formed on the crystal wafer 1, and is a view seen from the same direction as that shown in FIG. As shown in FIG. 7A, there is a residue on the vibration leg of the crystal resonator piece 7 formed by etching the crystal wafer 1, and etching for cutting out the crystal resonator piece 7 from the crystal wafer 1. Assuming that the mask is displaced up and down by a positional displacement amount e (the back mask is displaced to the right side in the drawing), the cross section of the drive leg 11 is vertically asymmetric as shown in the figure, and the main shaft 35 (shown by a thick line) of the drive leg 11 ) Is not parallel to the X axis and has a deviation angle θ1.

Therefore, since the direction in which the bending force is applied is different from the direction of the main shaft 35, the vibration is oblique, and leakage vibration is generated as indicated by S1 in FIG. 7B.
In a state where the crystal unit 10 is vibrated, a leak signal component is detected as a leak amount from detection signals from the detection electrode terminals 22 and 23.

[Electrode processing step: FIGS. 8 to 9]
Next, the electrode processing step (step ST4) of the manufacturing method of the present embodiment will be described.
In this electrode processing step, a part of the electrode is removed by irradiating with laser light based on the leakage amount information of each crystal resonator 10 acquired in the leakage amount measurement step. For example, a YAG laser can be used as the laser.

  FIG. 8 is a top view of the crystal unit 10 formed on the crystal wafer 1, and FIG. 9 is an example of a cross section of one drive leg 11 of the crystal unit 10, which is the same as the direction shown in FIG. It is the figure seen from the direction. 8 and 9 show an example in which the drive electrodes 20 and 21 are irradiated with laser light and a part of the drive electrodes 20 and 21 is removed. In the example shown in FIG. 8, the laser beam is irradiated in a spot-like circular shape.

  Spot-like laser light is continuously applied to the vicinity of the tips of the drive electrode 20a formed on the main plane of the drive leg 11 and the drive electrode 21c formed on the main plane of the drive leg 12 in order to obtain the width of the electrode. One end of the direction is continuously removed in the longitudinal direction of the electrode. In the portion where the electrodes are removed, the crystal surface of the crystal resonator element 7 is exposed, and a substantially rectangular adjustment area 30 is formed (area indicated by a broken line in FIG. 8). By forming the adjustment area 30, the electrode width W2 left in that portion becomes narrower than the electrode width W1 where the adjustment area 30 is not formed, as shown.

  The surface of the adjustment area 30 where the surface of the crystal is exposed is dissolved by re-etching in the balance adjustment process, which is a subsequent process, and the cross-sectional shapes of the drive legs 11 and 12 are adjusted to suppress leakage vibration. Therefore, the adjustment area 30 is formed based on the information on the leakage amount of each crystal resonator 10 acquired in the leakage amount measurement step.

[Balance adjustment process (etching process): FIG. 10]
Next, the balance adjustment process (step ST5) of the manufacturing method of this embodiment will be described. FIG. 10 is an example of a cross section of one drive leg 11 of the crystal unit 10, and is a view seen from the same direction as the direction shown in FIG.

  As described above, in the electrode processing step, the region where the drive electrodes 20 and 21 on the drive legs 11 and 12 are removed (adjustment) based on the information on the leak amount of each crystal resonator 10 acquired in the leak amount measurement step. Areas 30a, 30b) are formed.

  In this balance adjustment step, the crystal wafer 1 in which the drive electrodes of the drive legs 11 and 12 of each crystal resonator 10 are processed into a predetermined shape in the electrode processing step is immersed in an etching solution. As a result, as shown in FIG. 10A, etching is performed using the processed drive electrode as a mask, and the front and back surfaces of the crystal resonator element 7 exposed in the adjustment areas 30a and 30b are removed by etching. The thickness of the drive leg 11 is slightly reduced.

  As described above, the crystal in the adjustment areas 30a and 30b is removed by etching, so that the cross-sectional shape that is asymmetrical in the vertical direction is corrected, and the main shaft 35 is corrected as indicated by S2 in FIG. Thereby, as shown in FIG. 10B, leakage vibration when the crystal resonator 10 is driven is suppressed.

  As shown in FIGS. 7 to 10, the drive electrodes 20 and 21 of the drive legs 11 and 12 were removed in accordance with the direction of leakage vibration before adjustment in the leak amount measurement process, the electrode processing process, and the balance adjustment process. An adjustment area 30 is formed, and etching is performed using the drive electrodes 20 and 21 in which the adjustment area is formed as a mask to correct a cross-sectional shape that is asymmetrical in the vertical direction, and leakage vibration of the crystal unit 10 is suppressed.

  As a result, the leakage vibration can be adjusted without applying extra external force to the crystal unit, so that the crystal unit can stably and accurately adjust the leakage vibration without reducing the yield and reliability of the crystal unit. A method for manufacturing a vibrator can be provided.

[Description of Inter-electrode Short: FIGS. 10 to 12]
Here, a short circuit (insulation failure) between the electrodes of the crystal resonator that occurs after the balance adjustment process (etching process) will be described. 11 and 12 are explanatory diagrams showing a short state between the electrodes of the crystal resonator.

  When each electrode is formed on the crystal resonator piece 7 and then an etching process is performed, as shown by L in FIG. 10A, an electrode film (in the example of FIG. 10A, drive electrodes 20a and 20b). So-called side etching occurs in which the lower crystal portion disappears.

  As a result, as shown in FIG. 11, a part of the electrode film is separated from the drive electrode 20 a from which the underlying crystal has disappeared to form a ribbon-shaped electrode peeling portion 6. Contact with another electrode (in the example of FIG. 10A, the drive electrode 21b) causes a short circuit between the electrodes.

  Moreover, a part of such an electrode peeling part isolate | separates from an electrode film, and floats in a solution. When the floating electrode peeling portion is dried while adhering between electrodes of different polarities, a short circuit between the electrodes occurs in this portion. A filter for removing foreign substances is installed in the crystal etching tank and the cleaning tank, etc., but these ribbon-shaped electrode peeling portions are 1 μm wide, several hundred nanometers thick, and several tens μm long, Even a fine filter is difficult to remove.

  In addition to the electrode separation part, as shown in O of FIG. 12, some conductive foreign matter 8 is attached across electrodes of different polarities (in the example of FIG. 12, the drive electrode 20a and the drive electrode 21b). In this case, a short circuit between the electrodes occurs in the same manner.

[Voltage application process: FIGS. 13 to 14]
Next, the voltage application process (step ST6) of the manufacturing method of this embodiment will be described.
In the manufacturing process of the crystal unit, various electrical characteristic inspections of the crystal unit are performed on the wafer for the purpose of selecting defects as early as possible. In this electrical characteristic inspection, a probe is addressed to a terminal of each crystal resonator on the crystal wafer and connected to a measuring instrument to perform electrical measurement.

FIG. 13 is an explanatory diagram of a configuration example for performing the voltage application step, and a part of the configuration of the crystal unit 10 is omitted. FIG. 14 is an explanatory view showing a state in which an insulation failure between electrodes of the crystal resonator is removed.
As shown in FIG. 13, in the voltage application process of the present embodiment, the wiring from the drive electrode terminals 20 and 21 of the crystal resonator 10, the relay 25 that connects the power supply 27, the impedance between the drive electrodes, etc. OR connection is made to two of the relays 26 connected to the measuring instrument 28 to be measured. As the wiring branching relay used here, it is desirable to use a mechanical relay instead of a semiconductor relay in order to give a degree of freedom to the input current.

  When the drive electrode terminals 20 and 21 and the measuring instrument 28 are connected, the relay 25 is disconnected and the relay 26 is connected. When the drive electrode terminals 20 and 21 and the power source 27 are connected, the relay 25 is connected and the relay 26 is disconnected.

First, the relay 25 is disconnected, the relay 26 is connected, and the drive electrode terminals 20, 2
1 and the measuring instrument 28 are connected, and the impedance etc. between the drive electrodes of the crystal resonator 10 are measured by the measuring instrument 28. Here, when the short circuit between the electrodes of the crystal unit 10 has occurred, this short circuit is confirmed in the electrical characteristic inspection by the measuring instrument 28.

In this case, the relay 25 is connected and the relay 26 is disconnected, and the drive electrode terminals 20 and 21 and the power supply 27 are connected. For example, about 10 V is applied between the drive electrode 20a and the drive electrode 21b of the crystal resonator 10 by the power source 27 connected by the relay 25 in a closing time of 0.2 seconds.
Since the resistance value of the short portion of the short circuit between the electrodes described with reference to FIGS. 10 to 12 is about several Ω to several hundred Ω, the current flowing by this voltage application is about several tens of mA.

  With the heat generated by this current, as shown in O of FIG. 14, the short portion can be burned out and the insulation failure between the electrodes can be removed. If burning is not successful and the short state is not resolved, energy is continuously input to the crystal unit 10 and heat is generated indefinitely, resulting in a dangerous state. Therefore, the configuration shown in FIG. It is desirable to provide a configuration for limiting the above and the voltage application time. In the example in which about 10 V is applied at a charging time of 0.2 seconds as described above, for example, it is desirable to provide a configuration for performing a current limit of 100 mA.

  In the above description, an example in which voltage is applied by the power supply 27 to the crystal resonator 10 in which a short circuit has been confirmed in the electrical characteristic inspection by the measuring instrument 28 has been shown. However, the voltage applied by the power source 27 may be applied to the total number of the respective crystal resonators 10 formed on the crystal wafer 1 without checking the short circuit between the electrodes by the measuring instrument 28. In this case, the short part of the crystal unit 10 in which the short-circuit between the electrodes has occurred is burned out, and the insulation failure between the electrodes is removed.

  FIG. 13 shows a configuration in which a voltage is applied between the drive electrodes of the crystal unit 10 to remove the short-circuit between the electrodes. Separately, a voltage is applied between the detection electrodes of the crystal unit 10. For this purpose, a similar circuit may be connected, and a short circuit between the electrodes may be removed by applying a voltage between the detection electrodes. Further, when a short circuit is considered between the GND electrode and each of the other electrodes, a similar circuit for applying a voltage between the GND electrode and the other electrode is connected, and the GND electrode and the other electrode are connected. A voltage may be applied between the two to remove the short circuit between the electrodes.

  As described above, according to the manufacturing method of the present embodiment, a simple process of applying a predetermined voltage between the electrodes after etching the crystal resonator piece 7 (piezoelectric vibrating piece) on which each electrode is formed. Therefore, it is possible to remove the insulation failure caused by electrode peeling due to side etching. By performing the process from the outer shape forming process to the voltage applying process on the quartz wafer, a large number of quartz crystal vibrating pieces can be processed at once, and the quartz crystal vibrator can be manufactured efficiently.

  When the voltage application process is completed, each crystal resonator is separated from the crystal wafer and sealed with a sealing member to complete the product. However, the process after the voltage application process is not directly related to the present invention, so that Is omitted.

  In the description of the embodiment of the present invention described above, an example in which a balance adjustment process is performed as an etching process after electrodes are formed on a crystal resonator piece has been described. However, the present invention is not limited to this, and as an etching process, etching for processing a groove in a vibration leg, etching for adjusting a frequency of a crystal resonator, or orthogonality between driving vibration and detection vibration is established. Etching for adjustment or the like may be performed.

After the electrodes are formed on the crystal resonator piece, these etching steps are performed to generate side etching as shown in FIG. 10 (a), and an electrode in which a part of the electrode film as shown in FIG. 11 is separated. There is a possibility that a peeling portion is generated, and this electrode peeling portion comes into contact with another electrode to cause a short circuit between the electrodes. However, after that, by performing the voltage application process as described above, it is possible to remove the insulation failure caused by electrode peeling due to side etching.

DESCRIPTION OF SYMBOLS 1 Crystal wafer 2a, 2b Metal corrosion-resistant film 3a, 3b, 300 Photoresist 4a, 4b, 400a, 400b Photomask 5a, 5b Etching mask 6 Electrode peeling part 7 Crystal oscillator piece 8 Foreign material 10 Crystal oscillator 11, 12 Drive leg 13 Detection Leg 14 Base 20a, 20b, 20c, 20d, 21a, 21b, 21c, 21d Drive Electrode 20, 21 Drive Electrode Terminal 22a, 22b Detection Electrode 22, 23 Detection Electrode Terminal 22c GND Electrode 24 GND Electrode Terminal 25, 26 Relay 27 Power supply 28 Measuring instrument 30 Adjustment area 35 Spindle 200 Metal film

Claims (8)

An electrode forming step of forming a plurality of electrodes on the piezoelectric vibrating piece;
And a voltage applying step of applying a predetermined voltage between the electrodes and burning out the defective insulation portion by heat generated by the current. A method of manufacturing a piezoelectric device, comprising: An electrode forming step of forming a plurality of electrodes on the piezoelectric vibrating piece;
An etching step of etching the piezoelectric vibrating piece on which each of the electrodes is formed;
And a voltage application step of applying a predetermined voltage between the electrodes and burning out the defective insulation portion by heat generated by the current. A method for manufacturing a piezoelectric device, comprising: 3. The method of manufacturing a piezoelectric device according to claim 2, wherein in the etching step, the piezoelectric vibrating piece is etched using the electrodes as a mask to adjust the balance of the piezoelectric vibrating piece. A leakage amount measuring step for measuring a leakage amount of the piezoelectric vibrating piece in which each electrode is formed;
An electrode processing step of processing the electrode into a predetermined shape based on the measurement result of the leakage amount measurement step,
The method for manufacturing a piezoelectric device according to claim 3, wherein the etching step is performed using the electrode processed in the electrode processing step as a mask. 3. The method of manufacturing a piezoelectric device according to claim 2, wherein in the etching step, processing of a groove in the piezoelectric vibrating piece or adjustment of a frequency of the piezoelectric vibrating piece is performed. The piezoelectric vibrating piece is used for a vibration type gyro sensor,
The method for manufacturing a piezoelectric device according to claim 2, wherein adjustment for establishing orthogonality between drive vibration and detection vibration is performed in the etching step. An outer shape forming step of forming a plurality of the piezoelectric vibrating pieces having a predetermined shape on the piezoelectric wafer;
The said electrode formation process, the said etching process, and the said voltage application process are performed with respect to each said piezoelectric vibrating piece formed on the said piezoelectric wafer. The Claim 1 characterized by the above-mentioned. Of manufacturing a piezoelectric device. The method of manufacturing a piezoelectric device according to claim 1, wherein the piezoelectric vibrating piece is a quartz crystal vibrating piece.

Images