JP4777744B2 - Wafer body for piezoelectric vibrator and method for manufacturing piezoelectric vibrator - Google Patents

Description

  The present invention relates to a piezoelectric vibrator, an oscillator, a radio timepiece, an electronic device, a wafer body for a piezoelectric vibrator, and a method for manufacturing the piezoelectric vibrator.

In recent years, various piezoelectric vibrators have been used as a time source, a timing source of control signals, and the like in cellular phones and portable information terminal devices (see, for example, Patent Document 1). Among these piezoelectric vibrators, those equipped with a sealed container in which a lid member and a base member are joined and a piezoelectric vibrator plate disposed between the lid member and the base member are well known. ing. Such a piezoelectric vibrator is generally manufactured as follows. That is, the lid wafer serving as the lid member and the base wafer serving as the base member are overlapped and bonded with the vibrator wafer serving as the piezoelectric vibrator plate interposed therebetween. Then, individual piezoelectric vibrators can be obtained by cutting the lid wafer, vibrator wafer, and base wafer that are joined and integrated in a matrix direction with a dicing blade.
Here, for example, quartz is selected as the piezoelectric material, glass is selected for the lid member and the base member, and the quartz and glass are anodically bonded using a thin film of aluminum as a bonding film.
Japanese Unexamined Patent Publication No. 2000-223997

  However, the layer structure of the bonded wafer body bonded and integrated is glass, aluminum, crystal, aluminum, and glass in order from the lid wafer side, and is mainly composed of a brittle material. Therefore, in the cutting process using the dicing blade, the blade is clogged or clogged, and therefore, the chipping or cracking is likely to occur on the cut surface. These have a great influence on the appearance, quality and reliability of the vibrator. In particular, when the vibrator has been in a high temperature and high humidity condition for a long period of time, there is a concern that corrosion, leakage, etc. will occur starting from a place where chipping or microcracking occurs and the electrical characteristics of the vibrator will be greatly affected. There is. Therefore, in order to prevent this, the management of the blade is important, and there is a problem that the blade dressing work by sharpening the abrasive grains must be frequently performed. Moreover, even if the dressing operation as described above is performed, there is a limit to the use of the blade, and it is necessary to periodically replace the blade with a new blade within a short period of time.

  The present invention has been made in view of such circumstances, and can extend the life of the blade and facilitate the maintenance of the blade. Piezoelectric vibrator, oscillator, radio timepiece, electronic device, piezoelectric It is an object of the present invention to provide a vibrator wafer body and a method of manufacturing a piezoelectric vibrator.

In order to solve the above problems, the present invention provides the following means.
A piezoelectric vibrator according to the present invention is a piezoelectric vibrator formed by cutting a wafer body for piezoelectric vibrator, which is formed by stacking and joining a plurality of wafers, by dicing, and includes a plate-like lid member and a base member And a piezoelectric vibrator plate formed by surrounding a piezoelectric vibrator piece surrounded by a frame-shaped portion, and a sealed container that is overlapped and joined in the thickness direction, and the lid member and the base member. And an escape portion directed inward of the sealed container is formed on a side surface of the sealed container, and the escape portion is formed in advance on each of the plurality of wafers before the cutting. It is formed by the peripheral surface of the through-hole for cutting for reducing a cutting area.

In the piezoelectric vibrator according to the present invention, the piezoelectric vibrator wafer body is cut along the cutting through-hole by dicing, so that a clearance portion formed by the peripheral surface of the cutting through-hole is formed on the side surface of the sealed container. Is formed. Therefore, at the time of cutting, the cutting area by the blade is reduced by the amount of the through hole for cutting.
Thereby, it is possible to prevent the blade from being clogged or clogged as much as possible.
Moreover, it can make it easy to pinch | tighten a sealed container by making a tweezers contact | abut according to an escape part.

  Moreover, the piezoelectric vibrator according to the present invention is characterized in that the escape portion is formed over the entire length of the height of the sealed container.

  In the piezoelectric vibrator according to the present invention, since the escape portion is formed over the entire length of the height dimension of the hermetic container, the cutting through holes formed in each wafer before cutting are arranged in alignment with each other. Since the cutting is performed along the through holes for cutting, the cutting can be easily and reliably performed. Moreover, it can be made more easily pinched by tweezers.

  Further, the piezoelectric vibrator according to the present invention is characterized in that a plurality of the escape portions are formed so as to surround the periphery of the sealed container.

  In the piezoelectric vibrator according to the present invention, since a plurality of relief portions are provided so as to surround the periphery of the hermetic container, when the piezoelectric vibrator wafer body is cut into individual piezoelectric vibrators, The cutting area for the piezoelectric vibrator can be further reduced. Moreover, it can be made easy to pinch from various angles by tweezers.

An oscillator according to the present invention is characterized in that the piezoelectric vibrator according to any one of claims 1 to 3 is electrically connected to an integrated circuit as an oscillator.
A radio timepiece according to the present invention is characterized in that the piezoelectric vibrator according to any one of claims 1 to 3 is electrically connected to a filter unit.
An electronic apparatus according to the present invention includes the piezoelectric vibrator according to any one of claims 1 to 3.

  In the oscillator, the radio timepiece, and the electronic device according to these inventions, the same effect as the piezoelectric vibrator according to any one of claims 1 to 3 can be obtained.

  The piezoelectric vibrator wafer body according to the present invention includes a lid wafer in which a plurality of lid-side recesses are formed, a base wafer in which a plurality of base-side recesses are formed, and a plurality of piezoelectric vibrator pieces. A cutting line for cutting the lid wafer, the base wafer, and the vibrator wafer into the lid wafer, the base wafer, and the vibrator wafer, respectively. A cutting through-hole for reducing the cutting area is formed along the line.

In the piezoelectric vibrator wafer body according to the present invention, when the lid wafer, the base wafer and the vibrator wafer are cut along the cutting line, a cutting through hole is provided along the cutting line. Therefore, the cutting area of the lid wafer, the base wafer, and the vibrator wafer is reduced.
Thereby, it is possible to prevent the blade from being clogged or clogged as much as possible.

  The piezoelectric vibrator wafer body according to the present invention is characterized in that the lid wafer and the base wafer are overlapped and bonded with the vibrator wafer interposed therebetween.

  In the piezoelectric vibrator wafer body according to the present invention, since the lid wafer and the base wafer are overlapped and bonded with the vibrator wafer interposed therebetween, the lid wafer, the vibrator wafer, and the base The wafer can be cut easily and reliably.

  The piezoelectric vibrator wafer body according to the present invention is characterized in that the formation positions of the through holes for cutting of the lid wafer, the base wafer, and the vibrator wafer are the same.

  In the piezoelectric vibrator wafer body according to the present invention, the formation positions of the cutting through holes of the lid wafer, the base wafer, and the vibrator wafer are the same, so that the wafer can be cut easily and reliably. Can do.

  In the piezoelectric vibrator wafer body according to the present invention, the through-holes for cutting the lid wafer, the base wafer, and the vibrator wafer respectively include the lid-side recess, the base-side recess, and the A plurality of piezoelectric vibrator pieces are provided so as to individually surround the periphery of the piezoelectric vibrator piece.

  In the piezoelectric vibrator wafer according to the present invention, when the periphery of the lid-side concave portion, the base-side concave portion, and the piezoelectric vibrator piece is cut in the matrix direction, the cutting area for each piezoelectric vibrator can be further reduced. it can.

  The method for manufacturing a piezoelectric vibrator according to the present invention includes a sealed container in which a plate-like lid member and a base member are overlapped and joined in the thickness direction, and the lid member and the base member. And a piezoelectric vibrator plate having a piezoelectric vibrator piece surrounded by a frame-shaped portion, wherein the vibration is applied to the vibrator wafer serving as the piezoelectric vibrator plate. A vibrator side through hole forming step of forming a vibrator side cutting through hole for reducing a cutting area along a cutting line when cutting the child wafer, and a lid wafer serving as the lid member, A lid side through hole forming step for forming a lid side cutting through hole for reducing the cutting area along a cutting line when cutting the lid wafer, and the base wafer serving as the base member, Along the cutting line when cutting the base wafer A base side through hole forming step for forming a base side cutting through hole for reducing a cutting area, and a vibrator wafer having a vibrator side cutting through hole formed by the vibrator side through hole forming step A lid wafer having a lid-side cutting through-hole formed by the lid-side through-hole forming step, and a base wafer having a base-side cutting through-hole formed by the base-side through-hole forming step And a dicing step of cutting the lid wafer, the vibrator wafer, and the base wafer bonded by the bonding step along the cutting line.

In the piezoelectric vibrator manufacturing method according to the present invention, in the vibrator-side through-hole forming step, the vibrator-side cutting through is made along the cutting line when the vibrator wafer is cut into the vibrator wafer. A hole is formed. In the lid-side through-hole forming step, the lid-side cutting through-hole is formed in the lid wafer along a cutting line when the lid wafer is cut. Further, in the base side through hole forming step, a base side cutting through hole is formed in the base wafer along a cutting line when the base wafer is cut. Then, in the bonding step, the lid wafer having the lid side cutting through hole and the base wafer having the base side cutting through hole are bonded with the vibrator wafer having the vibrator side cutting through hole interposed therebetween. Is done. Further, in the dicing process, the lid wafer, the vibrator wafer, and the base wafer are cut along a cutting line. At this time, since each cutting through-hole is formed along the cutting line, the cutting area of the lid wafer, the vibrator wafer, and the base wafer is reduced.
Thereby, it is possible to prevent the blade from being clogged or clogged as much as possible.

  In the piezoelectric vibrator manufacturing method according to the present invention, the lid-side through-hole forming step includes a plurality of lid-side cutting through holes so as to surround a periphery of the region serving as the lid member. A plurality of base side cutting through holes are formed in the base wafer so as to surround a region to be the base member by the base side through hole forming step, and the vibrator side through hole forming step Thus, a plurality of vibrator side cutting through-holes are formed in the vibrator wafer so as to surround a region to be the piezoelectric vibrator plate.

  In the method for manufacturing a piezoelectric vibrator according to the present invention, the periphery of each of the region serving as the lid member, the region serving as the base member, and the region serving as the piezoelectric vibrator plate is cut in the matrix direction. At this time, since each cutting through-hole is formed so as to surround each periphery, the cutting area for each piezoelectric vibrator can be further reduced.

  In the piezoelectric vibrator manufacturing method according to the present invention, in the joining step, when the vibrator wafer is sandwiched and the lid wafer and the base wafer are overlapped at a predetermined rotational position, The lid-side cutting through-hole, the base-side cutting through-hole, and the vibrator-side cutting through-hole are arranged at positions that coincide with each other.

  In the method for manufacturing a piezoelectric vibrator according to the present invention, in the bonding step, the lid wafer and the base wafer are overlapped at a predetermined rotational position with the vibrator wafer interposed therebetween, and the lid-side cutting is performed. The through-hole, the base-side cutting through-hole, and the vibrator-side cutting through-hole are arranged at the same positions. Therefore, the lid wafer, the vibrator wafer, and the base wafer can be cut easily and reliably.

  According to the present invention, the blade can be prevented from being clogged or clogged as much as possible, so that the life of the blade can be extended and the maintenance of the blade can be facilitated.

(Embodiment 1)
Hereinafter, a crystal resonator (piezoelectric resonator) according to a first embodiment of the present invention will be described with reference to the drawings.
In FIGS. 1A and 1B, reference numeral 1 denotes a crystal resonator.
A crystal resonator 1 includes a crystal resonator plate (piezoelectric resonator plate) 2 made of crystal and formed in a rectangular shape, and a plate-shaped lid that is overlapped and joined in the thickness direction across the crystal resonator plate 2. And a sealed container 3 having a member 6 and a base member 7.

  As shown in FIG. 2, the quartz oscillator plate 2 includes a tuning fork type quartz oscillator piece (piezoelectric oscillator piece) 9 in which two vibrating arm portions 9a extending in parallel are integrally connected on the base end side. And a rectangular frame-shaped portion 10 surrounding the crystal resonator element 9. The crystal resonator element 9 and the frame-shaped portion 10 are integrally formed via the base end portion of the crystal oscillator piece 9. An electrode film 4 for applying a voltage to the crystal resonator piece 9 is formed on the front and back surfaces of the crystal resonator plate 2. The electrode film 4 is made of a conductive member such as aluminum. In FIG. 2, the electrode film 4 is shown in a simplified manner, but it is needless to say that the electrode film 4 is actually patterned according to various specifications and shapes.

  The lid member 6 and the base member 7 are made of glass such as soda lime glass. Of the two main surfaces of the lid member 6, a substantially rectangular lid-side recess 11 is formed on one main surface 6 a. Similarly, a substantially rectangular base-side recess 14 is formed on one main surface 7 a of the base member 7. The lid member 6 and the base member 7 are anodically bonded via the electrode film 4 with the lid-side recess 11 and the base-side recess 14 facing each other. Thus, by making the lid-side recess 11 and the base-side recess 14 face each other, the cavity 15 shown in FIG. 1B is formed in the sealed container 3, and the cavity 15 causes the crystal resonator piece to be formed. 9 vibrations are allowed. The airtight container 3 is hermetically sealed, and the cavity 15 is kept in a vacuum state.

In addition, external terminal connection portions 21 that are notched in an arc shape are provided at the four corners of the base member 7. The external terminal connection portion 21 is provided with an external terminal 20 that extends to the bottom surface of the sealed container 3 (the other main surface of the base member 7). The external terminal 20 is configured by forming an Au layer on a Cr layer formed as a base. The external terminal 20 is electrically connected to the electrode film 4.
In addition, a protective film 16 for preventing corrosion of the electrode film 4 is formed on the outer peripheral surface of the sealed container 3 except for the bottom surface. The protective film 16 is made of 0.1 wt% fluorocarbon of a fluorine-based coating agent having trimethylsiloxane at the end. As the protective film 16, for example, OPTOOL DSX (product name: manufactured by Daikin Industries, Ltd.) is used.

  Further, in the present embodiment, a relief portion 19 directed inward of the sealed container 3 is formed on the side surface of the sealed container 3. The escape portion 19 is formed over the entire length of the height dimension h of the sealed container 3. A plurality of escape portions 19 are formed so as to surround the periphery of the sealed container 3. That is, the escape portion 19 is formed along each side (long side portion or short side portion) of the sealed container 3 on each of the four side surfaces of the sealed container 3. Further, as will be described later, the escape portion 19 is formed by the peripheral surfaces of cutting through holes formed in advance in each of the lid wafer 27, the base wafer 30 and the vibrator wafer 24 shown in FIG. . That is, by cutting the lid wafer 27, the base wafer 30 and the vibrator wafer 24, the cutting through-holes are divided, and the peripheral surface of the cutting through-hole before cutting becomes the escape portion 19.

  Under such a configuration, when a predetermined voltage is applied to the external terminal 20, the voltage is applied to the crystal resonator element 9 through the electrode film 4. Then, due to the piezoelectric effect, the vibrating arms 9a bend and move with a predetermined period in a direction in which they approach or separate from each other, that is, in a reverse phase mode.

Next, a method for manufacturing the crystal unit 1 in the present embodiment will be described.
FIG. 3 is a flowchart showing the procedure of the method for manufacturing the crystal unit 1.
First, the quartz crystal ore is cut, polished to a predetermined thickness, and then washed to form a disk-shaped vibrator wafer 24 as shown in FIG. 4 (step S10). Then, a plurality of crystal vibrator pieces 9 are formed in the matrix direction on the vibrator wafer 24 by chemical treatment such as etching. A region surrounding each of the crystal resonator pieces 9 is a region of each crystal resonator plate 2. Further, simultaneously with the formation of the quartz crystal resonator element 9, four oscillator-side cutting through holes 25 are formed as shown in FIG. 5 so as to individually surround the plurality of crystal oscillator pieces 9. Step S11, vibrator-side through-hole forming step). That is, in the conventional process of forming the crystal resonator element 9 and the frame-shaped portion 10, the vibrator side cutting through-hole can be added without adding processes to the mask by simply adding the pattern for the vibrator side cutting through-hole 25 to the mask. 25 is formed quickly and easily. These vibrator-side cutting through holes 25 are for reducing the cutting area of the vibrator wafer 24 by the dicing blade 33 shown in FIG. Further, the vibrator-side cutting through hole 25 is formed along the cutting line C ₁ in the matrix direction by the dicing blade 33.

Then, in the electrode film forming step, a film made of aluminum is formed on the front and back surfaces of the vibrator wafer 24 by sputtering or vapor deposition. Then, patterning is performed by photolithography, etching, or the like, and an aluminum film is formed in a region that becomes the vibrating arm portion 9 a or the frame-like portion 10. This aluminum film becomes the electrode film 4 described above.
As shown in FIG. 5, the vibrator wafer 24 is formed with a plurality of vibrator pieces 9 and a frame portion 10 surrounding the vibrator pieces 9. Here, the frame-shaped portion 10 is electrically connected to the frame-shaped portion of another adjacent vibrator piece through the electrode film 4. As a result, in the bonding step (step S41) described later, when the vibrator wafer supplies voltage to one point of the wafer from the outside, the entire surface including the front and back surfaces of the vibrator wafer is set to the same potential. Is possible.

Next, as shown in FIG. 6, after the glass is polished and washed to a predetermined thickness, a disc-shaped lid wafer 27 is formed by removing the outermost work-affected layer by etching or the like (step S20). . Then, a plurality of lid-side recesses 11 are formed in the matrix direction on one main surface 27a of the lid wafer 27 by etching or the like (step S21). Further, as shown in FIG. 7, a lid-side cutting through hole 28 is formed so as to individually surround the plurality of lid-side recesses 11 (step S <b> 22, lid-side through-hole forming step). These lid side cutting holes 28 are formed along the cutting line C ₂ by the blade.
In this embodiment, a lid-side through-hole forming step is added to the conventional process. However, since the lid-side through-hole forming step is a batch process, a plurality of sheets can be processed quickly at the same time.

Next, as shown in FIG. 8, after polishing and cleaning the glass to a predetermined thickness, a disk-shaped base wafer 30 is formed by removing the outermost processed layer by etching or the like (step S30). . Then, a plurality of base-side recesses 14 are formed in the matrix direction on one main surface 30a of the base wafer 30 by etching or the like (step S31). Further, as shown in FIG. 9, through holes 32 are formed by blasting or the like at the four corners of each rectangular region that surrounds the plurality of base-side recesses 14 and becomes the base member 7. Simultaneously with the formation of the through holes 32, four base side cutting through holes 31 are formed by blasting or the like so as to individually surround the plurality of base side recesses 14 (step S32, base side through hole formation). Process). In other words, the base-side cutting through-hole 31 can be formed quickly and easily by adding a pattern for the base-side cutting through-hole 31 to the mask in the conventional process of forming the through-hole 32 without increasing the number of steps. . These base-side cutting through holes 31 are formed along a cutting line C ₃ by the dicing blade 33.

The vibrator-side cutting through-hole 25, the lid-side cutting through-hole 28, and the base-side cutting through-hole 31 are each formed in a rectangular shape, and are chamfered so that each edge becomes R. . Furthermore, each of the through holes 25, 28, 31 is formed to have the same size and is formed at the same position in the matrix direction. FIG. 10 shows the vibrator wafer 24 after the vibrator side through hole forming step, the lid wafer 27 after the lid side through hole forming step, and the base wafer 30 after the base side through hole forming step. The piezoelectric vibrator wafer body 35 shown in FIG.
Then, as shown in FIG. 10, the vibrator wafer 24 is sandwiched between the lid wafer 27 and the base wafer 30 in the thickness direction, and the respective wafers 24, 27, 30 are overlapped. Then, alignment is performed at a predetermined position in accordance with a reference mark provided on each wafer 24, 27, 30 (step S40). That is, the wafers 24, 27, and 30 are aligned according to a predetermined rotational position. At this time, the through holes 25, 28, and 31 are arranged to coincide with each other, and a plurality of through holes that penetrates the entire length of each wafer 24, 27, and 30 in the height direction are formed in the matrix direction. In addition, the respective lid-side recesses 11 and the base-side recesses 14 face each other, whereby a cavity 15 is formed.

Then, the three wafers 24, 27, and 30 that are overlapped are put into an anodic bonding apparatus, and anodic bonding is performed by applying a predetermined voltage in a predetermined temperature atmosphere (step S41, bonding process). When a positive potential (usually ground potential) is supplied to one point of the vibrator wafer 24, the electrode films 4 formed on the front and back surfaces of the vibrator wafer are all applied to the same potential. Negative electrode conductive electrodes are uniformly adhered to the non-bonded surfaces of the lid wafer 27 and the base wafer facing the vibrator, and an electric field is generated between the electrode film 4 and the conductive electrodes. To do. The electrode film 4 is bonded to the lid wafer 27 and the base wafer 27 by application of heat energy and electric field energy. The three bonded wafers 24, 27, and 30 form a bonded wafer body.
Subsequently, a V-shaped guide groove serving as a guide line for the dicing blade 33 at the time of full cut is formed on the surface of the base wafer 30 (step S42). Here, this guide groove is referred to as a bevel cut 34b shown in FIG. The bevel cutting 34b extends to the row and column directions so as to surround the periphery of the base side recess 14, the line of extension of the bevel cut 34b is cutting line C _3.

  Then, the above-described external terminal 20 is provided through the through hole 32 (step S43). That is, a metal mask is applied to the other main surface of the base wafer 30, and a thin film is formed by sputtering or vapor deposition. Accordingly, a pair of external terminals 20 extending from the inner surface of the through hole 32 to the other main surface of the base wafer 30 is provided. The external terminal 20 is connected to the electrode film 4 through the through hole 32.

Further, a bevel cut 34 f similar to the base wafer 30 is formed on the surface of the lid wafer 27. The bevel cutting 34f extends to the row and column directions so as to surround the periphery of the lid side recess 11, the line of extension of the bevel cut 34f are disconnected line C _2. Then, the other main surface of the base wafer 30 is affixed to the tape, and the lid wafer 27, the vibrator wafer 24, the base wafer 30, and the front and back surfaces of the vibrator wafer 24 are cut without cutting the tape. Only the formed electrode film 4 is cut. That is, the bonded piezoelectric vibrator wafer body 35 is placed on a dicing saw and cut in the matrix direction by the dicing blade 33 along the bevel cuts 34b and 38f (step S44, dicing process).

At this time, as shown in FIG. 12, the cutting area of the dicing blade 33 is reduced as follows. That is, conventionally, since each through hole 25, 28, 31 is not formed, the cutting area per one crystal unit 1 and one side of the side surface is the width dimension w and the height dimension h of the crystal unit 1. It is calculated by the product of In this embodiment, since the dicing blade 33 advances along each through-hole 25, 28, 31, the region of each through-hole 25, 28, 31 becomes a non-cutting region. That is, the non-cutting area determined by the product of the width dimension w ₁ and the height dimension h of each through-hole 25, 28, 31 is subtracted from the cutting area, thereby reducing the total cutting area.

  In this dicing step, when the piezoelectric vibrator wafer body 35 is cut individually, each of the through holes 25, 28, 31 is divided into two with reference to the axis line directed in the length direction. The peripheral surfaces of the divided through holes 25, 28, and 31 serve as the escape portion 19 described above. Further, the through holes 32 formed at the four corners of the above-described rectangular region of the base wafer 30 are divided into four by the dicing blade 33, and each of these divided portions is an arc-shaped external terminal connecting portion as described above. 21.

Next, frequency adjustment is individually performed on the individually cut crystal resonator pieces 9 and adjusted to a predetermined frequency (step S45).
Then, the whole is immersed in the fluorocarbon solution while being attached to the tape. Then, the whole is taken out, placed for a predetermined time, and then heated. Then, the above-mentioned protective film 16 is formed and coated on the outer surface of each sealed container 3 (step S46). When each wafer is immersed, the solution may enter from the gap between the tapes. However, since the surface of the external terminal 20 is made of Au and the solution is made of fluorocarbon, a protective film is formed on the external terminal 20. It is prevented from forming.
Then, when the tape is peeled off, each vibrator becomes the crystal vibrator 1 shown in FIGS. 1 (a) and 1 (b).

As described above, according to the crystal resonator 1 of the present embodiment, the relief portion 19 formed by the peripheral surface of each through hole 25, 28, 31 is provided, so that the cutting area by the dicing blade 33 is reduced. As a result, the dicing blade 33 can be prevented from being clogged or clogged as much as possible. Therefore, the life of the dicing blade 33 can be extended, and maintenance of the dicing blade 33 can be facilitated. Further, since the cutting area is reduced, the traveling speed of the dicing blade 33 can be increased, and the dicing process can be speeded up. Furthermore, since the cutting area by the dicing blade 33 is reduced, it is possible to suppress an increase in sliding frictional heat with the piezoelectric vibrator wafer body 35 and the electrode film 4, and the piezoelectric vibrator wafer body 35 due to a difference in thermal expansion coefficient. Can be prevented from being deformed.
Further, the tweezers are brought into contact with the escape portion 19 so that the sealed container 3 can be easily sandwiched.
Further, since the escape portion 19 is formed over the entire length of the height dimension h of the sealed container 3, each through hole 25, 28, 31 formed in each wafer 24, 27, 30 before cutting is one. Since they are arranged and cut along the through-holes 25, 28 and 31, the piezoelectric vibrator wafer body 35 can be cut easily and reliably.
Further, since a plurality of relief portions 19 are provided so as to surround the periphery of the sealed container 3, when the piezoelectric vibrator wafer body 35 is cut into the individual crystal vibrators 1, the individual crystal vibrators are provided. The cutting area for 1 can be further reduced.

Further, according to the piezoelectric vibrator wafer body 35 in the present embodiment, since the through holes 25, 28, and 31 are formed, cutting by the dicing blade 33 when cutting the piezoelectric vibrator wafer body 35. It is possible to prevent the dicing blade 33 from being crushed or clogged as much as possible.
Further, since the positions of the through holes 25, 28, and 31 coincide with each other, a through hole that penetrates the piezoelectric vibrator wafer body 35 is formed, so that the piezoelectric vibrator wafer body 35 can be easily and reliably cut. can do.
Furthermore, since the plurality of through holes 25, 28, and 31 are provided so as to surround the respective rectangular regions, the cutting area by the dicing blade 33 can be further reduced.

  Further, according to the method for manufacturing a piezoelectric vibrator in the present embodiment, since the dicing blade 33 is advanced along the through holes 25, 28, and 31 in the dicing process, the cutting area can be reduced. Therefore, it is possible to prevent the dicing blade 33 from being clogged or clogged as much as possible.

Here, the experimental result about this invention is demonstrated below.
The thickness dimension of the vibrator wafer 24 was 130 μm, the thickness dimension of the lid wafer 27 was 0.4 mm, and the thickness dimension of the base wafer 30 was 400 μm. The dimensions of the crystal unit 1 were 3.2 mm for the long side and 1.2 mm for the short side. The thickness dimension of the dicing blade 33 was 150 μm.

The dressing operation was performed after the two piezoelectric vibrator wafer bodies 35 were cut. The dressing time was about 3 minutes per time. Specifically, it took about 2 minutes to prepare the dress plate, change the program of the dicing apparatus, and load and unload the dress plate, and the actual dressing time was about 1 minute.
The cutting (full cut) time was about 25 minutes. Specifically, the time required for workpiece preparation, program switching, loading and unloading of the workpiece is approximately 3 minutes, the actual disconnection time is approximately 20 minutes, and adjustments are made during cutting ( It took about 2 minutes to enter the program.

  Thereby, the improvement effect was able to be acquired as follows. That is, if the dressing operation is performed every time one piece of the piezoelectric vibrator wafer body 35 is cut, it takes 28 minutes in total for the cutting and dressing work for one piece of the piezoelectric vibrator wafer body 35. On the other hand, since the cutting area by the dicing blade 33 is reduced, the dressing operation can be performed every time two piezoelectric vibrator wafer bodies 35 are cut. In this case, the piezoelectric vibrator wafer body 35 For one piece, the total of cutting and dressing work was 24 minutes (however, the program switching was set to 1 minute). Therefore, the shortening time was 4 minutes, improving by 14.3%.

  Further, the dicing blade 33 is replaced every time the eight piezoelectric vibrator wafer bodies 35 are cut. As a result, the cutting area by the dicing blade 33 is reduced, so that replacement can be performed every time 16 pieces are cut. Therefore, the life of the dicing blade 33 is extended, and the economy can be improved.

In the present embodiment, the four through holes 25, 28, and 31 are provided along the sides of the rectangular region. However, the present invention is not limited to this, and the formation position and number of the through holes 25, 28, and 31 can be changed as appropriate. . For example, as shown in FIG. 13, the through holes 25, 28, 31 may be provided so as to extend from the four corners of the rectangular region to the long side and the short side, that is, to be orthogonal to the four corners. Although only the vibrator wafer 24 is shown in FIG. 13, it goes without saying that through holes are formed in the lid wafer 27 and the base wafer 30 in the same manner. In this case, the through hole is also used as a base-side cutting through hole.
Here, the vibrator wafer 24 shown in FIG. 13 is formed with a plurality of vibrator pieces 9 and a frame-like portion 10 surrounding the vibrator pieces 9. Here, the frame-shaped portion 10 is electrically connected to the frame-shaped portion of another adjacent vibrator piece through the electrode film 4. Thereby, in the bonding step (step S41), the vibrator wafer can have the same potential on the entire surface including the front and back surfaces of the vibrator wafer when a voltage is supplied to one point of the wafer from the outside. It has become.

In the above description, the piezoelectric vibrator piece is the crystal vibrator piece 9 made of quartz. However, the present invention is not limited to this, and vibrator pieces made of various piezoelectric single crystal materials such as lithium niobate may be used. Good.
In addition, although the protective film 16 is made of the OPTOOL DSX, the present invention is not limited to this, and the member can be appropriately changed.
In addition, the lid wafer 27 and the base wafer 30 are anodically bonded. However, the present invention is not limited to this, and the bonding method can be appropriately changed. For example, eutectic bonding may be used.

(Embodiment 2)
Next, a second embodiment of the present invention will be described with reference to FIG.
In FIG. 14, the code | symbol 38 shows the oscillator which concerns on the 2nd Embodiment of this invention.
The oscillator 38 is configured by using the crystal resonator 1 of the first embodiment as an oscillator.
The oscillator 38 includes a substrate 40 on which an electronic component 39 such as a capacitor is mounted. An integrated circuit 43 for an oscillator is mounted on the substrate 40, and the crystal unit 1 is mounted in the vicinity of the integrated circuit 43. The electronic component 39, the integrated circuit 43, and the crystal unit 1 are electrically connected by a wiring pattern (not shown). Each component is molded with a resin (not shown).

Under such a configuration, when a voltage is applied to the crystal resonator 1, the above-described crystal resonator element 9 vibrates, and the vibration is converted into an electric signal by the piezoelectric characteristics of the crystal, and the integrated circuit 43 receives the vibration. Input as an electrical signal. The input electrical signal is subjected to various processes by the integrated circuit 43 and output as a frequency signal. Thereby, the crystal unit 1 functions as an oscillator.
Further, by selectively setting the configuration of the integrated circuit 43, for example, an RTC (real-time clock) module or the like as required, the operating date and time of the device and external device can be set in addition to a single-function oscillator for a clock. Functions such as control and provision of time and calendar can be provided.

  As described above, according to the oscillator 38 in the present embodiment, not only can the same effect as the crystal resonator 1 according to the first embodiment be obtained, but also a stable and highly accurate frequency signal can be obtained over a long period of time. it can.

(Embodiment 3)
Next, a third embodiment of the present invention will be described.
In the present embodiment, a portable information device will be described as an electronic device including the crystal unit 1 in the first embodiment.
In FIG. 15, reference numeral 46 indicates a portable information device, and the functional configuration of the portable information device 46 will be described with reference to FIG. 15.

The portable information device 46 includes a power supply unit 47 for supplying power. The power supply unit 47 is made of, for example, a lithium secondary battery.
The power supply unit 47 includes a control unit 48 that performs various controls, a clock unit 51 that counts time, a communication unit 52 that communicates with the outside, a display unit 56 that displays various types of information, and respective functions. A voltage detection unit 53 for detecting the voltage of the unit is connected in parallel. The power supply unit 47 supplies power to each functional unit.

  The control unit 48 controls each function unit to control the operation of the entire system such as transmission and reception of audio data, measurement and display of the current time, and the like. The control unit 48 includes a ROM in which a program is written in advance, a CPU that reads and executes the program written in the ROM, and a RAM that is used as a work area for the CPU.

  The timer unit 51 includes an integrated circuit including an oscillation circuit, a register circuit, a counter circuit, an interface circuit, and the like, and the crystal unit 1. When a voltage is applied to the crystal unit 1, the above-described crystal unit piece vibrates, and the vibration is converted into an electric signal by the piezoelectric characteristics of the crystal and input to the oscillation circuit as an electric signal. The output of the oscillation circuit is binarized and counted by a register circuit and a counter circuit. Then, signals are transmitted to and received from the control unit 48 via the interface circuit, and the current time, current date, calendar information, etc. are displayed on the display unit 56.

The communication unit 52 has functions similar to those of a conventional mobile phone, and includes a radio unit 57, a voice processing unit 58, a switching unit 61, an amplification unit 62, a voice input / output unit 63, a telephone number input unit 66, and a ring tone generation unit. 67 and a call control memory unit 68.
The wireless unit 57 exchanges various data such as audio data with the base station via an antenna. The audio processing unit 58 encodes and decodes the audio signal input from the radio unit 57 or the amplification unit 62. The amplifying unit 62 amplifies the signal input from the audio processing unit 58 or the audio input / output unit 63 to a predetermined level. The voice input / output unit 63 includes a speaker, a microphone, and the like, and amplifies a ringtone and a received voice or collects a speaker voice.

  In addition, the ring tone generator 67 generates a ring tone in response to a call from the base station. The switching unit 61 switches the amplifying unit 62 connected to the voice processing unit 58 to the ringing tone generating unit 67 only when an incoming call is received, so that the ringing tone generated in the ringing tone generating unit 67 causes the amplifying unit 62 to be switched. To the voice input / output unit 63. The call control memory unit 68 stores a program related to incoming / outgoing call control of communication. The telephone number input unit 66 includes, for example, number keys from 0 to 9 and other keys. By pressing these number keys, the telephone number of the call destination is input.

  When the voltage applied to each functional unit such as the control unit 48 by the power supply unit 47 falls below a predetermined value, the voltage detection unit 53 detects the voltage drop and notifies the control unit 48 of the voltage drop. . The predetermined voltage value at this time is a value set in advance as a minimum voltage necessary to stably operate the communication unit 52, and is, for example, about 3V. Upon receiving the voltage drop notification from the voltage detection unit 53, the control unit 48 prohibits the operations of the radio unit 57, the voice processing unit 58, the switching unit 61, and the ring tone generation unit 67. In particular, it is essential to stop the operation of the wireless unit 57 with high power consumption. Further, the display unit 56 displays that the communication unit 52 has become unusable due to insufficient battery power.

That is, the operation of the communication unit 52 can be prohibited by the voltage detection unit 53 and the control unit 48, and that effect can be displayed on the display unit 56. This display may be a text message, but as a more intuitive display, a x (X) mark may be attached to the telephone icon displayed at the top of the display surface of the display unit 56.
In addition, the crystal unit 1 includes a power cutoff unit 69 that can selectively cut off the power supply of the portion related to the function of the communication unit 52, and the function of the communication unit 52 can be reduced by the power cutoff unit 69. Stop surely.

  As described above, according to the portable information device 46 of the present embodiment, not only can the same effect as the crystal resonator 1 according to the first embodiment be displayed, but also stable and highly accurate timing information can be displayed over a long period of time. can do.

(Embodiment 4)
Next, a fourth embodiment of the present invention will be described.
In the present embodiment, a radio-controlled timepiece will be described as an electronic device including the crystal resonator 1 in the first embodiment.
In FIG. 16, reference numeral 71 denotes a radio timepiece.

  The radio clock 71 is a clock having a function of receiving a standard radio wave including time information and automatically correcting and displaying the correct time. In Japan, there are transmitting stations (transmitting stations) that transmit standard radio waves to Fukushima Prefecture (40 kHz) and Saga Prefecture (kHz), each transmitting standard radio waves. Long waves such as 40 kHz or 60 kHz have both the property of propagating the ground surface and the property of propagating while reflecting the ionosphere and the ground surface, so the propagation range is wide, and the above two transmitting stations cover all of Japan. .

A functional configuration of the radio timepiece 71 will be described with reference to FIG.
The antenna 74 receives the long standard radio wave of 40 kHz or 60 kHz. The long standard radio wave is obtained by subjecting time information called a time code to AM modulation on the 40 kHz or kHz carrier wave.
The received long standard wave is amplified by an amplifier 75 and filtered and tuned by a filter (filter unit) 80 having a plurality of crystal resonators 1. The crystal unit 1 in this embodiment includes crystal units 76 and 79 having resonance frequencies of 40 kHz and 60 kHz that are the same as the carrier frequency.
Further, the filtered signal having a predetermined frequency is detected and demodulated by the detection and rectification circuit 81. Subsequently, the time code is taken out via the waveform shaping circuit 84 and counted by the CPU 85. The CPU 85 reads information such as the current year, accumulated date, day of the week, and time. The read information is reflected on the RTC 86, and accurate time information is displayed.

  Since the carrier wave is 40 kHz or 60 kHz, the crystal vibrator portions 76 and 79 are preferably vibrators having the tuning fork type structure described above. Taking 60 kHz as an example, it is possible to configure the tuning fork type resonator element as a dimension example having a total length of about 2.8 mm and a base width dimension of about 0.5 mm.

  As described above, according to the radio-controlled timepiece 71 in the present embodiment, not only can the same effect as the crystal resonator 1 according to the first embodiment be obtained, but also the time can be counted stably over a long period of time with high accuracy. be able to.

  The technical scope of the present invention is not limited to the above embodiment, and various modifications can be made without departing from the spirit of the present invention.

1A and 1B are diagrams showing a crystal resonator as a first embodiment of the present invention, where FIG. 1A is a plan view of the crystal resonator, and FIG. 1B is a side view of the crystal resonator. It is a perspective view which decomposes | disassembles and shows the crystal oscillator of FIG. 2 is a flowchart showing a procedure of a manufacturing method of the crystal unit of FIG. It is a top view of the wafer for vibrators formed in the process of the manufacturing method of a crystal vibrator. FIG. 5 is an enlarged plan view showing a state where a vibrator side cutting through hole is formed in the vibrator wafer of FIG. 4. It is a top view of the wafer for lids formed in the process of the manufacturing method of a crystal oscillator. It is a top view which expands and shows a mode that the through-hole for lid | cover side cutting | disconnection was formed in the wafer for lid | covers of FIG. It is a top view of the wafer for base formed in the process of the manufacturing method of a crystal oscillator. It is a top view which expands and shows a mode that the through-hole for base side cutting | disconnection was formed in the wafer for bases of FIG. It is explanatory drawing which shows a mode that three wafers are piled up after each through-hole is formed. It is explanatory drawing which shows a mode that the wafer body for piezoelectric vibrators is cut | disconnected in a dicing process. It is explanatory drawing which shows the mode of the cutting area by a dicing blade in a dicing process. FIG. 6 is a plan view showing a modification of the vibrator side cutting through hole of the vibrator wafer of FIG. 5. It is a top view which shows the oscillator as the 2nd Embodiment of this invention. It is a block diagram which shows the portable information device as the 3rd Embodiment of this invention. It is a block diagram which shows the radio timepiece as the 4th Embodiment of this invention.

Explanation of symbols

1 Crystal resonator (piezoelectric resonator)
2 Quartz vibrator plate (piezoelectric vibrator plate)
3 Sealed container 6 Lid member 7 Base member 9 Crystal vibrator piece (piezoelectric vibrator piece)
DESCRIPTION OF SYMBOLS 10 Frame-shaped part 11 Cover side recessed part 14 Base side recessed part 19 Relief part 24 Vibrator wafer 25 Vibrator side cutting through hole 27 Cover wafer 28 Cover side cutting through hole 30 Base wafer 31 Base side cutting through hole 35 Wafer body for piezoelectric vibrator 38 Oscillator 46 Portable information device (electronic device)
71 Radio clock 80 Filter (filter part)
h Height dimension (height dimension of sealed container)

Claims (7)

A lid wafer in which a plurality of lid side recesses are formed;
A base wafer having a plurality of base side recesses formed thereon;
A vibrator wafer on which a plurality of piezoelectric vibrator pieces are formed,
In each of the lid wafer, the base wafer, and the vibrator wafer, a corner portion is curved at a portion where a cutting line is perpendicular to the lid wafer, the base wafer, and the vibrator wafer. A wafer member for a piezoelectric vibrator, wherein a cross-shaped through hole is formed. 2. The piezoelectric vibrator wafer body according to claim 1 , wherein the lid wafer and the base wafer are overlapped and bonded with the vibrator wafer interposed therebetween. 3. The piezoelectric vibrator wafer body according to claim 2 , wherein the formation positions of the through holes of the lid wafer, the base wafer, and the vibrator wafer coincide with each other. A plurality of the through holes of the lid wafer, the base wafer, and the vibrator wafer are provided so as to individually surround the lid-side recess, the base-side recess, and the piezoelectric vibrator piece, respectively. the piezoelectric vibrator wafer member as claimed in any one of claims 3, characterized in that is. A plate-shaped lid member and a base member are disposed between the sealed container and the lid member and the base member, and the piezoelectric vibrator piece is surrounded by a frame-shaped portion. A piezoelectric vibrator manufacturing method comprising: a formed piezoelectric vibrator plate;
Formed on the vibrator wafer serving as the piezoelectric vibrator plate is a substantially cross-shaped vibrator-side through-hole with a curved corner at a portion where the cutting line and the cutting line intersect when the vibrator wafer is cut. A vibrator side through hole forming step,
A lid-side through hole that forms a substantially cross-shaped lid-side through-hole having a curved corner at a portion where a cutting line and a cutting line when the lid wafer is cut are perpendicular to the lid wafer serving as the lid member Forming process;
A base-side through-hole that forms a substantially cross-shaped base-side through-hole with a curved corner at a portion where the cutting line and the cutting line at the time of cutting the base wafer are orthogonal to the base wafer serving as the base member Forming process;
A lid wafer having the lid-side through-hole formed by the lid-side through-hole forming step, with the vibrator wafer having the transducer-side through-hole formed by the transducer-side through-hole forming step interposed therebetween; A bonding step of bonding the base wafer having the base side through hole formed by the base side through hole forming step;
And a dicing step of cutting the lid wafer, the vibrator wafer, and the base wafer bonded by the bonding process along the cutting line. In the lid-side through-hole forming step, a plurality of the lid-side through-holes are formed in the lid wafer so as to surround a region to be the lid member,
In the base side through hole forming step, a plurality of the base side through holes are formed in the base wafer so as to surround the periphery of the region to be the base member,
By the vibrator-side through-hole forming step, the vibrator wafer, according to claim 5, characterized in that so as to surround the periphery of the region to be the piezoelectric vibrator plate a plurality of said vibrator-side through-hole is formed A method for manufacturing the piezoelectric vibrator according to claim 1. In the joining step, when the lid wafer and the base wafer are overlapped at a predetermined rotational position with the vibrator wafer interposed therebetween,
The method for manufacturing a piezoelectric vibrator according to claim 5 , wherein the lid-side through hole, the base-side through hole, and the vibrator-side through hole are arranged at positions that coincide with each other.

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