JP2007057411A - Oscillator, its manufacturing method, and physical quantity sensor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an oscillator of high accuracy and high reliability, its manufacturing method, and a physical quantity sensor. <P>SOLUTION: In the oscillator manufacturing method, the oscillator having a base and an oscillating leg projecting from the base is processed by laser beams. The oscillator manufacturing method has a process of condensing the laser beams having transmitted through the inside of the oscillator to a predetermined position of the oscillator and removing a part of the oscillator. Thus, a part difficult to be processed conventionally can be easily processed, and the degree of freedom in processing is improved. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a method for manufacturing a tuning fork type vibration body including a base portion and a plurality of vibration legs formed to protrude from the base portion, and more particularly to a method for manufacturing a vibration body having a vibration mode adjustment step and a physical quantity sensor.

  In recent years, vibratory gyro sensors have been used in a wide range of fields such as attitude control of aircraft, vehicles, etc., angular velocity detection of navigation systems, and camera shake control of video cameras. Among such vibration type gyro sensors, a piezoelectric gyro using a vibrating body made of a piezoelectric material is becoming mainstream.

  As described above, in a situation where the piezoelectric gyro is used in a wide range of fields, there is an increasing demand for higher reliability and higher accuracy of the vibrator.

  Ideally, by achieving a vibrating body that vibrates at the designed resonant frequency and has a stable vibration balance, a highly reliable and highly accurate piezoelectric gyro can be obtained as a result. Due to the processing accuracy and the variation in the electrical characteristics of the piezoelectric material, it is not always possible to manufacture the vibrator in an ideal state.

  Therefore, in the past, vibration adjustment processing for adjusting the resonance frequency and adjusting the vibration balance was always performed in the manufacturing process of the vibrating body. This process is generally referred to as a vibration mode adjustment process.

  Hereinafter, a conventional method for manufacturing a vibrating body will be described (for example, see Patent Document 1). FIG. 9 is a view showing a structure of a conventional general vibrating body and a cross section of a vibrating leg thereof. As shown in FIG. 9A, the vibrating body 10 is composed of a tuning fork-type piezoelectric body 100 having two vibrating legs 11 protruding from a base 12, and a voltage applied to the piezoelectric body 100 on the piezoelectric body 100. An electrode 200 is formed to add and vibrate.

  When the conventional vibrating body 10 having such a configuration is used in a piezoelectric gyro, the angular velocity is detected using the Coriolis principle. The Coriolis principle is a principle that a vibration f0 in a certain direction is given to the vibrating leg 11 in a steady state, and a vibration fs is generated in a direction perpendicular to the vibration f0 when a rotation ω is added thereto. The vibrating body 10 detects the angular velocity by electrically detecting the vibration fs.

  Usually, crystal, piezoelectric ceramics, or the like is used for the piezoelectric body 100, and the outer shape thereof is formed by etching or mechanical cutting. However, regardless of which processing method is used, variations in processing dimensions always occur, and therefore, the weight balance of the vibrating legs 11 is unbalanced. If an imbalance occurs in the weight balance, the vibration f0 in the steady state vibrates differently from the designed vibration mode, and an accurate angular velocity cannot be detected.

  Therefore, conventionally, as shown in FIG. 9A, a part of the vibration leg 11 is subjected to removal processing, and the removal unit 101 is provided to balance the weight balance of the vibration leg 11 and change the vibration mode of the vibration f0. I was adjusting.

FIG. 10 is a diagram showing a process for adjusting the vibration mode of a conventional vibrator. FIG. 11 is a perspective view showing a method for adjusting a vibration mode using a conventional rotary polishing tool (ruder). FIG. 12 is a diagram showing a method for adjusting the vibration mode of the vibration f1 using a conventional rotary polishing tool (luter). FIG. 13 is a diagram showing a method for adjusting the vibration mode of the vibration f2 using a conventional rotary polishing tool (rutor).

  FIG. 14 is a perspective view showing a conventional method for adjusting a vibration mode using a polishing tape containing an abrasive. In the conventional vibration mode adjustment process, first, as shown in FIG. 10A, an electrode 200 is formed on the piezoelectric body 100, and a predetermined electric field is applied to the piezoelectric body 100 to examine the vibration mode of the vibration legs. In most cases, since the weight balance of the vibrating legs is broken at this stage, as shown in FIG. 10A, a vibration mode of vibration f1 that vibrates in a direction different from the desired direction is generated. .

  Therefore, in order to balance the weight balance, a process of removing a part of the piezoelectric body 100 is performed as shown in FIG. Conventionally, this removal processing includes a processing method in which a predetermined portion of the vibrating leg 11 is ground with a fine rotary grinding tool 400 (generally referred to as a leuter) as shown in FIG. 11, or an abrasive as shown in FIG. A processing method is used in which a predetermined portion of the vibrating leg 11 is ground by sliding a polishing tape 600 including a roller with a roller 610. By this grinding method, the vibration mode of the vibration f1 is adjusted to the desired vibration f0.

  FIGS. 12 and 13 are diagrams when the vibration mode is adjusted by the rotary grinding tool 400. At this time, the location where the piezoelectric body 100 (particularly the vibration leg portion) is cut according to the vibration modes of the vibrations f1 and f2. Change the weight balance. However, when grinding with the rotary polishing tool 400, it is necessary to avoid that the rotary polishing tool 400 contacts the package 500 and damages the package 500.

  Therefore, when the vibration mode is f1, the piezoelectric body 100 is processed as shown in FIG. 12, and when the vibration mode is f2, the piezoelectric body 100 is processed as shown in FIG. At this position, the rotary polishing tool 400 can adjust the vibration mode, that is, adjust the weight balance without contacting the package 500.

  At that time, a part of the dust 800 generated by grinding always adheres to the vibrating leg 11. If the dust 800 adheres, even if the weight balance is adjusted, there is a risk that the dust 800 gradually peels off over time and the weight balance gradually collapses. Therefore, in general, in order to ensure the reliability, as shown in FIG. 10C, the dust 800 reattached to the vibrating leg 11 is removed by washing, and the vibrating body 10 that generates the vibration f0 that is a desired vibration mode is obtained. Was getting.

  Also, a method of adjusting the weight balance by processing using laser light in the vibration mode adjustment process has been proposed (see, for example, Patent Document 2). FIG. 15 is a perspective view showing a conventional method for adjusting a vibration mode by processing using laser light. According to this, the weight balance is adjusted by irradiating the corner portion of the vibration leg 11 with laser light and removing a part of the vibration leg 11.

  At that time, a plurality of laser beams were irradiated from different angles in order to concentrate the energy of the laser in a minute region. Naturally, in this method, it is necessary to avoid damaging the package by irradiating the package with laser light. Therefore, it was necessary to pay close attention to the direction of laser light irradiation.

JP 2002-243451 A (page 7, FIG. 3, FIG. 10, FIG. 12) Japanese Patent Laying-Open No. 2004-93158 (page 4, FIG. 3)

  In the conventional manufacturing method of a vibrating body, in order to obtain a vibration mode as designed, a vibration mode adjustment step is essential. Further, this vibration mode adjustment step is generally performed by adjusting the vibration leg by a grinding method or the like, or by removing a part of the vibration leg by a laser processing method using a laser beam.

  In general, in the vibration mode adjustment step, the weight balance is adjusted by changing the location where the piezoelectric body 100 (particularly the vibration leg portion) is cut according to the vibration modes of the vibrations f1 and f2. However, when grinding with the rotary polishing tool 400 as shown in FIG. 11, places where the rotary polishing tool 400 can be processed without contacting the package 500 are limited. Therefore, when the vibration mode is f1, as shown in FIG. 12, the corner portion of the vibration leg made of the piezoelectric body 100 is processed, and when the vibration mode is f2, the piezoelectric body 100 starts from the piezoelectric body 100 as shown in FIG. Another corner of the vibrating leg was being machined.

  This is because at this position, the rotary polishing tool 400 can adjust the vibration mode, that is, adjust the weight balance without contacting the package 500. FIG. 12 and FIG. 13 show the case where processing is performed with the rotary polishing tool 400. However, when processing with the polishing tape 600 as shown in FIG. 14, a plurality of lasers as shown in FIG. Even in the case of processing by direct irradiation with light, only the same part as in FIGS. 12 and 13 could be processed for the same reason that the package 500 becomes an obstacle.

  In the conventional vibration mode adjustment process, in the case of the vibration modes f1 and f2 in which the weight balance is largely lost, it is necessary to increase the amount of grinding in order to balance the weight balance. However, there are a limited number of places that can be processed as described above. Therefore, especially when the weight balance is greatly lost, the removal portion 101 is scraped to the extent that it covers the electrode 200 as shown in FIG. 9 (b), which is a cause of deteriorating electrical characteristics. In the worst case, the electrode 200 may be scraped to such an extent that it can be completely disconnected electrically.

  An object of the present invention is to provide a highly accurate and reliable method for manufacturing a vibrating body and a physical quantity sensor.

  In order to solve the above-described problems, a method of manufacturing a vibrating body according to the present invention includes a vibrating body manufacturing method in which a vibrating body having a base portion and a vibrating leg that protrudes from the base portion is processed by laser light. The method includes the step of condensing the laser beam transmitted through the inside of the body at a predetermined position of the vibrating body to remove a part of the vibrating body.

  Further, the vibrating body has a surface on the laser beam irradiation side and a back surface located on the opposite side of the surface, and irradiates the laser beam from the surface side to collect the laser beam on the back surface. It is desirable to remove a part of the vibrating body.

  The vibrating body further includes a base material having a base and a vibrating leg, and an electrode for driving the vibrating body on the base material. Laser light is irradiated from the front surface, and laser light is applied to the electrode provided on the back surface. It is desirable to condense and remove a part of the electrode.

Furthermore, it is desirable that the step is a step of adjusting the vibration mode of the vibrating leg by removing a part of the vibrating leg in the vibrating body.

  Further, the laser light is preferably a femtosecond laser.

  Furthermore, it is desirable that the vibrator is a crystal vibrator.

  In addition, the vibrating body of the present invention is characterized by being manufactured using the above-described manufacturing method of a vibrating body.

  The physical quantity sensor of the present invention is characterized in that a physical quantity applied from the outside is detected by using the vibrating body manufactured by the above-described vibrating body manufacturing method.

  Further, this physical quantity sensor is preferably a vibration type gyro sensor.

(Function)
In the above-described means of the present invention, not only the processing of the surface irradiated with the laser beam but also the laser beam is transmitted through the vibrating body made of a transparent material and condensed at a predetermined position, thereby collecting the predetermined laser beam. Only the part of can be processed.

  By doing so, it has become possible to process even a portion that was conventionally blocked by a package or the like and was unable to reach the rotary polishing tool or polishing tape.

  In addition, by focusing the laser beam on the back surface of the vibrating body located on the opposite side of the surface irradiated with the laser light, the back surface of the vibrating body that could not be processed in the past (the bonding surface side with the package) It can be processed.

  Further, if the above means is used, in a vibrating body including a tuning fork-type base material having a base and a vibrating leg and an electrode formed on the base material, the back electrode is formed by laser light transmitted through the base material. Can be processed. Thus, even if a short circuit of the electrode is found after the vibrating body is attached to the package, the electrode disposed on the back surface can be processed and corrected.

  If the above means is used, even if the vibrating body is attached to the package, the vibration mode can be adjusted by processing the back surface of the vibrating body, that is, the surface bonded to the package. As a result, the area on the back side (bonding surface side with the package) that could not be processed in spite of being an effective area for adjusting the vibration mode can be processed. It can be increased to 2 times (conventionally only on the front surface, but in the present invention, it can be processed on both the front surface and the back surface).

  Further, since the area that can be processed is increased, it is possible to adjust a vibration mode that cannot be adjusted completely, and it is possible to adjust the defect, thereby improving the yield.

  In addition, since the area where the vibrator can be processed is increased compared to the conventional case, the processing area can be dispersed and the amount of processing per unit area can be reduced. As a result, there is almost no possibility that even a large amount of processing is performed at one location and even the electrode is scraped off, and electrical characteristics are not deteriorated and electrical disconnection is not caused.

In the above means of the present invention, a femtosecond laser is used as the laser beam. A femtosecond laser is a laser that is irradiated only for several tens to several hundreds of femtoseconds, and is characterized in that it can be processed with little thermal and chemical damage to the workpiece. In addition, this femtosecond laser can transmit a transparent material if the energy amount per unit area is kept low without condensing, while it can be condensed to increase the energy amount per unit area. One of the major features of other laser methods is that even transparent materials can be processed.

Conventionally widely used laser light such as excimer laser and Co ₂ laser has been transmitted through the transparent material, so that the transparent material could not be processed. However, if a femtosecond laser having the above-described characteristics is used, the amount of energy per unit area can be increased by transmitting a transparent material as in the present invention and then condensing at a predetermined position. Therefore, only a predetermined position can be processed even if it is a transparent material. Therefore, it is very effective for processing a vibrating body made of transparent quartz.

  Since the physical quantity sensor of the present invention uses the vibrating body manufactured by the above means, it becomes a highly accurate and reliable physical quantity sensor. Further, by using a vibration type gyro sensor as the physical quantity sensor, the angular velocity can be detected with high accuracy.

  According to the method for manufacturing a vibrating body of the present invention, a highly accurate and reliable vibrating body can be obtained. In addition, according to the present invention, a highly accurate and reliable physical quantity sensor can be provided.

(First embodiment)
The most important thing in manufacturing a vibrating body is to generate stable vibration. By using a vibrating body that generates stable vibration, it is possible to provide a highly reliable device with high accuracy (for example, a vibration type acceleration sensor or a vibration type gyro sensor). Therefore, in general, when a vibrating body is manufactured, a vibration mode adjustment process is always required so that stable vibration can be obtained. In the present embodiment, the vibration mode adjustment process according to the present invention will be described below.

  In the present embodiment, the vibration mode adjustment process as described below is incorporated in the method for manufacturing a vibrator. FIG. 1 is a cross-sectional view of a vibration leg showing a method of adjusting a vibration mode of vibration f1 in the method of manufacturing a vibrating body according to the present invention. FIG. 2 is a cross-sectional view of a vibration leg showing a method for adjusting a vibration mode of vibration f2 in the method for manufacturing a vibration body according to the present invention.

  FIG. 3 is a cross-sectional view of the vibrating leg processed by adjusting the vibration mode of the vibration f1 in the method of manufacturing a vibrating body according to the present invention. FIG. 4 is a cross-sectional view of a vibrating leg processed by adjusting the vibration mode of the vibration f2 in the method for manufacturing a vibrating body according to the present invention. FIG. 5 is a perspective view of a vibrating body whose vibration mode is adjusted by the method for manufacturing a vibrating body of the present invention.

  In this embodiment, the vibration mode adjustment is performed by processing the vibration leg 11 of the tuning-fork type vibrating body 10 having two vibration legs 11 protruding from the base 12 as shown in FIG. It was. The vibrating body 10 of the present embodiment has a structure in which an electrode 200 is formed on a piezoelectric body 100 made of quartz.

  In this embodiment, the piezoelectric body 100 made of quartz is formed by a wet etching method. At that time, etching anisotropy peculiar to quartz occurs. As a result, the cross-sectional shape of the vibrating leg 11 does not become rectangular, but is formed in an asymmetric shape as shown in FIGS.

  Further, the shape (the cross-sectional shape of the vibrating leg 11) does not necessarily become the same shape due to variations in etching conditions and the like. As a result, as shown in FIG. 1 and FIG. 2, the vibration body 10 has the vibration mode f1 or f2, and needs to be adjusted according to each vibration mode.

  For example, when the vibrating body 10 that vibrates in the vibration mode of the vibration f1 is formed, in order to balance the weight balance, the surface A of the piezoelectric body 100 shown in FIG. It is effective to process the B surface of the piezoelectric body 100 shown in FIG.

  In the present invention, when processing the A surface (the surface on the side irradiated with the laser beam 300), the laser beam is irradiated with the focus on the A surface, and the B surface (the back surface located on the side opposite to the A surface) is irradiated. In the case of processing, the processing is performed with the focal point of the laser beam transmitted through the piezoelectric body 100 (in the present embodiment, made of crystal) made of a transparent material focused on the B surface.

  By doing so, the removal portion 101 as shown in FIG. 3A is processed in FIG. 1A, and the removal portion 102 as shown in FIG. 3B is processed in FIG. As a result, the weight balance can be balanced.

  On the other hand, in the case where a vibrating body that vibrates in the vibration mode of vibration f2 is created, in order to balance the weight balance, the C surface of the piezoelectric body 100 shown in FIG. It is effective to process the front surface) or to process the D surface (the back surface opposite to the C surface) of the piezoelectric body 100 shown in FIG. is there.

  In the present invention, when processing the C surface, the laser beam is focused on the C surface and irradiated, and when processing the D surface, the inside of the piezoelectric body 100 (crystal in this embodiment) made of a transparent material. The laser beam that has passed through is focused on the D plane for processing.

  By doing so, the removal unit 101 as shown in FIG. 4A is processed in FIG. 2A, and the removal unit 102 as shown in FIG. 4B is processed in FIG. 2B. As a result, the weight balance can be balanced.

  In the vibration mode adjustment method of the present invention as described above, it is effective to use a femtosecond laser as the laser beam. A femtosecond laser is a laser that is irradiated only for several tens to several hundreds of femtoseconds, and is characterized in that it can be processed with almost no thermal and chemical damage to a workpiece.

  In addition, this femtosecond laser can transmit a transparent material if the energy amount per unit area is kept low without condensing, while it can be condensed to increase the energy amount per unit area. Also, it has a feature that even a transparent material can be processed. Therefore, as in the present invention, it is possible to process only a predetermined surface by focusing the femtosecond laser beam transmitted through the piezoelectric body 100 made of a transparent material on the predetermined surface. .

  Thus, in this embodiment, the vibrating body 10 for use as a piezoelectric gyro was manufactured. As shown in FIG. 5A, the vibrating body 10 includes a tuning fork type piezoelectric body 100 having two vibrating legs 11 projecting from a base 12, and a voltage applied to the piezoelectric body 100 formed on the piezoelectric body 100. In addition, it includes an electrode 200 for vibrating, and is joined to the package 500 on one plane of the base 12. As shown in FIG. 5A, the vibration leg 11 is attached in a state of being lifted from the package 500.

When such a tuning-fork type vibrating body 10 is used for a piezoelectric gyro, the angular velocity is detected using the Coriolis principle. The Coriolis principle is a principle in which a vibration f0 in a certain direction is given to the vibrating leg 11 in a steady state, and when a rotation ω is added thereto, a vibration fs is generated in a direction perpendicular to the vibration f0. By detecting fs electrically, angular velocity can be detected. Therefore, the vibration f0 generated in the steady state cannot be detected with high accuracy unless the vibration f0 is stably oscillated in a certain direction.

  In the present embodiment, since the piezoelectric body 100 made of quartz is processed by the wet etching method, the cross-sectional shape of the vibrating leg 11 is formed asymmetrical. As a result, the weight balance of the vibrating legs 11 is unbalanced. If imbalance occurs in the weight balance, the vibration f0 in the steady state vibrates differently from the designed vibration mode, and an accurate angular velocity cannot be detected. Therefore, the process of balancing the weight balance and adjusting the vibration mode is necessary. It is absolutely necessary.

  Since the vibrating body 10 of the present embodiment is in the state of the vibration mode f2, the femtosecond laser light is irradiated by both irradiation methods shown in FIGS. 2A and 2B, and the vibration becomes f0. Was processed as follows. As a result, as shown in FIG. 5B, the two removing portions 101 and 102 are formed in the piezoelectric body 100 that is a vibration leg, and thereby the vibration mode is adjusted to an optimum state, that is, the vibration is adjusted to f0. I was able to.

  In this embodiment, in both the irradiation methods of FIGS. 2A and 2B, the irradiation conditions of the femtosecond laser are as follows: pulse energy = 10 μJ / pulse, frequency = 1 kHz, scanning speed = 500 μm / sec, Processing was performed by setting the scanning distance = 1 mm and the number of scanning times = 2.

  As shown in FIG. 5A, the vibrating body 10 whose vibration mode is adjusted according to the present embodiment is provided at two locations on the front surface (the side not facing the package 500) and the back surface (the bonding surface side of the package) of the vibration leg 11. Removal portions 101 and 102 are formed. In this respect, the present invention is superior to the conventional vibration mode adjustment process.

  In the conventional vibration mode adjustment process (a method of grinding with a rotary grinding tool or a method of applying a laser beam directly to a processing surface), the package 500 becomes an obstacle and the back surface of the vibration leg 11 (the bonding surface side of the package) is processed. It was not possible to make adjustments, and adjustments had to be made only at one location of the removal unit 101. For this reason, as shown in FIG. 9B, there are many cases where the electrode 200 has to be processed so much that it is scraped off. This is a major cause of deteriorating electrical characteristics and causing electrical disconnection, and is one of the factors that reduce the reliability of the vibrator 10.

  However, in the present invention, the region that can be processed to adjust the vibration mode has doubled (the conventional one that can only be processed at one location can now be processed at two locations), so that per unit area can be processed. The processing amount can be halved. For this reason, the vibration mode can be adjusted without cutting the electrode 200, and much higher reliability than before can be obtained.

  In addition, since the adjustable region has increased, it is now possible to adjust a vibrating body whose weight balance has been greatly lost, which could not be adjusted in the past. As a result, the yield was significantly improved.

In the present embodiment, any material may be used for the electrode 200, but the present invention is more effective particularly when a transparent electrode, for example, an electrode made of ITO, SnO ₂ or the like is used. This is because if the electrode 200 is a transparent material, the laser beam can be transmitted, the workable area can be further expanded, and the vibration mode can be adjusted more easily.

(Second Embodiment)
FIG. 6 is a view showing a method of manufacturing a vibrating body for processing the side surface of the vibrating leg according to the present invention. In the present embodiment, as shown in FIG. 6A, the piezoelectric body 100 is irradiated with laser light 300 irradiated from the front surface (surface on the laser light 300 irradiation side) to the back surface (surface opposite to the front surface) of the piezoelectric body 100. The light was condensed at a predetermined light condensing position P inside. In the present embodiment, the condensing position P is set to a portion located on the inner side by about 5 μm from the side surface of the piezoelectric body 100 to be processed.

  The laser beam 300 condensed at the condensing position P has a radius of 5 to 10 μm around the condensing position P, although it depends on the amount of energy. Therefore, by condensing the laser at the condensing position P, it was possible to process the side surface of the piezoelectric body 100 as shown in FIG. Note that the irradiation conditions of the femtosecond laser in this embodiment were set such that pulse energy = 10 μJ / pulse, frequency = 1 kHz, scanning speed = 500 μm / sec, scanning distance = 0.8 mm, and number of scans = 1.

  In the present embodiment, the vibration mode of the vibration f2 in the state of FIG. 6A is changed as shown in FIG. The vibration mode of the vibration f0 can be adjusted.

(Third embodiment)
FIG. 7 is a view showing a method of manufacturing a vibrator provided with the piezoelectric thin film of the present invention. FIG. 7 shows the cross-sectional shape of the vibrating leg. The vibrating body used in the present embodiment is made of a lower electrode 210 made of Pt, a piezoelectric thin film 120 made of PZT, and Au on the surface of a transparent structure 710 made of quartz glass as a base material and having a base and a vibrating leg. The upper electrode 220 is a vibrating body patterned in a desired shape.

  Since the vibration mode used in the present embodiment was f2, the femtosecond laser light was irradiated so that it was in focus on the E plane as shown in FIG. Note that the irradiation conditions of the femtosecond laser in this embodiment were set such that pulse energy = 10 μJ / pulse, frequency = 1 kHz, scanning speed = 500 μm / sec, scanning distance = 0.8 mm, and number of scans = 1.

  As a result of the adjustment processing of the vibration mode, as shown in FIG. 7B, the removal portion 102 was formed in the transparent structure 700, the weight balance was balanced, and the desired vibration f0 could be obtained.

  In this way, the manufacturing method of the present invention can be used even for a vibrator having a structure in which the piezoelectric thin film 120 is formed on the transparent structure 700. In this embodiment, quartz glass is used as the transparent structure 710. However, the present invention can be used even with materials other than quartz glass, such as sapphire and plastic materials.

  In addition, the embodiment of the present invention has been described using a vibrating body having two vibrating legs, but it goes without saying that the present invention can be applied even when there are one or three or more vibrating legs.

(Fourth embodiment)
The present invention can be used not only for adjusting the vibration mode but also for correcting electrode patterns and other shapes. The method will be described below.

FIG. 8 is a view showing a method of manufacturing a vibrating body for correcting an electrode pattern according to the present invention. FIG. 8 shows a cross section of the piezoelectric body 100 of the vibration body for a vibration type acceleration sensor. In the vibrating body for a vibration type acceleration sensor according to the present embodiment, the piezoelectric body 100 as a base material is formed of quartz, and electrodes 205 made of ITO are formed at four corners (four corners) of the piezoelectric body 100. ing. ITO is a material that is widely used for liquid crystal displays and the like as a conductive material having transparency.

  The vibrating body for a vibration type acceleration sensor according to the present embodiment is configured to operate normally only after the electrodes 205 formed at the four corners of the piezoelectric body 100 are divided. However, due to some processing defect in the manufacturing process, the electrode 205 sometimes short-circuited on the back surface side of the piezoelectric body 100 as shown in FIG.

  In the present embodiment, as shown in FIG. 8A, the laser beam 300 irradiated from the front surface to the back surface of the piezoelectric body 100 is condensed on the plane (G surface) of the electrode 205. Thus, a part of the electrode 205 formed on the back surface is processed and can be divided into four electrodes 205 as shown in FIG. Thereby, the short circuit defect of an electrode is eliminated and the vibration body for vibration type acceleration sensors which operate | move normally can be obtained.

  In the present embodiment, the vibrator provided with the electrode 205 made of ITO, which is a transparent material, has been described as an example. However, the vibrator provided with the electrode 205 made of Au, Cu, a material having no transparency. Even if it exists, this invention can be utilized. In that case, the laser beam 300 is condensed at the interface between the piezoelectric body 100 and the electrode 205. At this time, it is desirable to set the power of the laser beam 300 to a level at which the electrode 205 is processed without processing the piezoelectric body 100. By doing so, it is possible to process only the electrode 205 without damaging the piezoelectric body 100.

  In addition, although this embodiment demonstrated the manufacturing method of the vibrating body for vibration type acceleration sensors, it is not necessarily restricted to the vibrating body for vibration type acceleration sensors. It is effective not only for gyro sensors but also for vibrating devices such as crystal oscillators.

It is sectional drawing of the vibration leg which showed the adjustment method of the vibration mode of the vibration f1 in the manufacturing method of the vibrating body of this invention. It is sectional drawing of the vibration leg which showed the adjustment method of the vibration mode of the vibration f2 in the manufacturing method of the vibrating body of this invention. It is sectional drawing of the vibration leg processed by adjustment of the vibration mode of the vibration f1 in the manufacturing method of the vibrating body of this invention. It is sectional drawing of the vibration leg processed by adjustment of the vibration mode of the vibration f2 in the manufacturing method of the vibrating body of this invention. It is a perspective view of the vibrating body which adjusted the vibration mode with the manufacturing method of the vibrating body of the present invention. It is the figure which showed the manufacturing method of the vibrating body which processes the side surface of the vibration leg of this invention. It is the figure which showed the manufacturing method of the vibrating body provided with the piezoelectric thin film of this invention. It is the figure which showed the manufacturing method of the vibrating body which corrects an electrode pattern by this invention. It is the figure which showed the structure of the conventional general vibration body, and the cross section of the vibration leg. It is the figure which showed the adjustment process of the vibration mode of the conventional vibrating body. It is the perspective view which showed the adjustment method of the vibration mode by the conventional rotary polishing tool (luter). It is the figure which showed the adjustment method of the vibration mode of the vibration f1 by the conventional rotary polishing tool (ruder). It is the figure which showed the adjustment method of the vibration mode of the vibration f2 by the conventional rotary polishing tool (ruder). It is the perspective view which showed the adjustment method of the vibration mode by the abrasive tape containing the conventional abrasive | polishing agent. It is the perspective view which showed the adjustment method of the vibration mode by the process using the conventional laser beam.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Vibrating body 11 Vibrating leg 12 Base part 100 Piezoelectric body 120 Piezoelectric thin film 101,102,103 Removal part 200,205 Electrode 210 Lower electrode 220 Upper electrode 300 Laser beam 400 Rotary polishing tool 500 Package 600 Polishing tape 610 Roller 700,710 Transparent structure Body 800 dust

Claims (9)

In a method of manufacturing a vibrating body that processes a vibrating body having a base and a vibrating leg that protrudes from the base by laser light,
A method of manufacturing a vibrating body, comprising: condensing laser light transmitted through the inside of the vibrating body at a predetermined position of the vibrating body to remove a part of the vibrating body. The vibrator has a surface that is a side on which the laser beam is irradiated and a back surface that is located on the opposite side of the surface.
2. The method of manufacturing a vibrating body according to claim 1, wherein the laser beam is irradiated from the front side, the laser beam is condensed on the back surface, and a part of the vibrating body is removed. The vibrating body further includes a base material having the base and the vibrating legs, and an electrode for driving the vibrating body on the base material,
The said laser beam is irradiated from the said surface, The said laser beam is condensed on the said electrode provided in the said back surface, The manufacturing of the vibrating body of Claim 2 characterized by the above-mentioned is removed. Method. 4. The method according to claim 1, wherein the step is a step of adjusting a vibration mode of the vibrating leg by removing a part of the vibrating leg in the vibrating body. 5. The manufacturing method of the vibrating body of description. The method for manufacturing a vibrating body according to any one of claims 1 to 4, wherein the laser beam is a femtosecond laser. The method for manufacturing a vibrating body according to claim 1, wherein the vibrating body is a crystal vibrating body.   A vibrating body manufactured using the method for manufacturing a vibrating body according to any one of claims 1 to 6.   A physical quantity sensor that detects a physical quantity applied from the outside using the vibrating body according to claim 7.   The physical quantity sensor according to claim 8, wherein the physical quantity sensor is a vibration gyro sensor.

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