JP2000288883A - Manufacture of quartz oscillator and manufacturing device therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To thinly and stably machine a quartz wafer and to hardly generate damage to the quartz wafer. SOLUTION: In this device, a ring-like grinding wheel 4 mounted on one surface of a wheel spindle stock 2 is disposed such that the grinding wheel 4 partially overlaps a rotary table 6 in plan. While the rotary table 6 can rotate around a rotation shaft 6a. A holding jig 10 is mounted and fixed on a surface of the rotary table 6. A quartz wafer 20 is sucked and held on a surface of a holding plate of the holding jig 10. An arc-shaped electrode member 8 faces a portion of the grinding wheel 4 in which the grinding wheel 4 does not overlap the rotary table 6 in plan, at a prescribed interval. An electrolytic coolant is supplied from plural opening parts 8b formed in a surface of the electrode member 8.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a quartz oscillator and a jig for grinding a wafer, and more particularly to a technique suitable for processing a thin quartz wafer for forming a quartz oscillator.

[0002]

2. Description of the Related Art In general, when manufacturing a quartz oscillator, a quartz wafer obtained by cutting a quartz crystal into a plate with a predetermined crystal orientation is thinned by polishing, and the thickness is reduced from several tens μm to several hundred μm.
It is designed to be processed into a parallel plate having a thickness of about m.
This crystal wafer is mirror-finished by finish grinding, etching, or the like, and further cut appropriately to form a surface electrode or the like, thereby forming a crystal resonator.

[0003] The most common method of processing a quartz oscillator is to perform processing using a polishing apparatus called a plane lapping machine. In a flat lapping machine, a gear-shaped holding frame having an opening called a carrier is arranged between a pair of upper and lower stools, and a crystal wafer is accommodated in the opening of the carrier and sandwiched between the upper and lower stools. The carrier is made to perform planetary motion while supplying loose abrasive grains between the upper and lower platens to polish both front and back surfaces of the quartz wafer. The carrier is provided with teeth on the outer peripheral portion, and the teeth are engaged with a sun gear at the center of the surface plate and an internal gear on the outer peripheral side of the surface plate, and the sun gear and the internal gear are appropriately adjusted. The polishing action can be performed in a random direction by rotating in the direction shown in FIG. In this polishing method, a quartz wafer is subjected to a plurality of steps in order from a thick state, for example, three steps of rough processing, intermediate processing, and finishing processing, and gradually thinned to finally obtain a surface roughness close to a mirror surface. Like that.

[0004]

However, in the above-mentioned conventional method, the characteristics of the crystal unit are greatly affected in the course of performing a plurality of processes such as rough machining, intermediate machining, and finishing with a flat lapping machine. In addition, there is a problem that the shift of the cut angle which gives the increases. If the surface roughness is gradually reduced in a plurality of steps as described above, an error occurs with respect to the cut angle of the polished surface in each step, so that as the number of polishing steps increases, the shift of the cut angle increases. .

Further, in the above method, since the crystal wafer is accommodated in the opening of the carrier and the grinding process is performed, corners of the crystal wafer are damaged due to collision between the carrier and the crystal wafer, and this fragment is generated. There is a risk of damaging the surface of the crystal wafer. In particular, in order to manufacture a high-precision, high-frequency quartz crystal unit, it is necessary to make the quartz wafer thin and to process it with high accuracy. In addition, since the carrier needs to be formed thinner than the quartz wafer in the processing by the flat lapping machine, the carrier is also extremely thin, and the carrier is likely to undulate during the processing. Therefore,
The possibility that cracks or chips are generated in the crystal wafer itself increases, and an accident that the crystal wafer jumps out of the carrier due to the undulated carrier easily occurs. When this accident occurs, the protruding quartz wafer breaks, and the other quartz wafer being processed at the same time is brought into an unrecoverable state. Therefore, the conventional method has a problem that an extremely thin quartz wafer cannot be supplied stably.

Accordingly, the present invention has been made to solve the above problems, and an object of the present invention is to provide a method for manufacturing a quartz wafer.
An object of the present invention is to provide a processing method that can be processed thinner than before, and is less likely to cause damage to a quartz wafer and can be processed stably.

[0007]

In order to solve the above-mentioned problems, a method of manufacturing a crystal unit according to the present invention comprises attaching a crystal wafer to a grinding jig, and attaching the crystal wafer to a support. A holding member made of a porous material configured to receive an exhausting action from a surface portion other than the exposed surface portion, and a suction force generated based on the exhausting action on the exposed surface portion of the holding member. While the crystal wafer is held by suction, the conductive base is eluted by electrolysis while the electrolytic solution is in contact with the surface of the grindstone formed by embedding the abrasive grains in the conductive base while dressing is performed. Grinding the quartz wafer by electrolytic in-process dressing processing in which the quartz wafer and the grindstone are relatively moved while the surface of the grindstone is in contact with the surface of the quartz wafer to perform surface processing. And wherein the door.

According to the present invention, the crystal wafer is stably and surely secured by holding the crystal wafer by suction on the exposed surface of the holding member made of a porous material and grinding it by electrolytic in-process dressing. Because it can be held and subjected to grinding, even if it is grinding,
Alternatively, even if the crystal wafer is processed to be extremely thin, the risk of breakage of the crystal wafer can be reduced. Also, by performing grinding while always sharpening the grindstone by electrolytic in-process dressing processing, even fine abrasive grains can be processed quickly, so there is no need to perform multi-stage polishing processing as in the conventional polishing method Also, it can be processed thinner than the conventional method.

In the present invention, the porous material is preferably a sintered body made of a granular material.

According to the present invention, by forming the porous material from the sintered body using the granular material as a raw material, a sufficient mechanical property can be secured while securing the air permeability necessary for holding by suction through the holding member. Since the strength can be obtained, the quartz wafer can be securely and securely held on the exposed surface portion. In this case, in particular, by forming the holding member from a ceramic material such as alumina or zirconia, both sufficient mechanical strength and corrosion resistance to an electrolytic solution and the like can be obtained.

In each of the above inventions, it is preferable that a liquid is arranged on the exposed surface portion of the holding member, and the quartz wafer is sucked and held by the exhaust action via the liquid.

According to the present invention, the liquid is sucked into the holding member by applying an exhausting action in a state where the liquid is arranged on the exposed surface of the holding member, and the crystal wafer is placed on the exposed surface through the liquid. Is held by suction. Therefore, a liquid exists between the crystal wafer and the exposed surface, and the airtightness between the two is improved, so that the suction force of the crystal wafer can be increased and the flatness of the crystal wafer in the suction holding state is improved. Can be done. As a result, the crystal wafer can be ground more safely and reliably, and the flatness of the processed crystal wafer can be improved. Further, since the liquid sucked into the holding member leaks out onto the exposed surface by relaxing the exhausting action, the crystal wafer can be very easily removed from the grinding jig after processing, and the crystal wafer can be extremely removed. Even if it is processed thinly, it can be handled safely.

In each of the above-mentioned inventions, it is preferable that, during the grinding process, the quartz wafer is suction-held on the exposed surface portion by the exhausting operation in a state where the liquid is filled in the inside of the holding member. .

According to the present invention, the liquid exists between the quartz wafer and the exposed surface portion, and the airtightness between the two is improved, so that the chucking force of the quartz wafer can be increased and the quartz wafer can be attracted. The flatness in the holding state can be improved. As a result, the crystal wafer can be ground more safely and reliably, and the flatness of the processed crystal wafer can be improved. Further, since the liquid sucked into the holding member leaks out onto the exposed surface by relaxing the exhausting action, the crystal wafer can be very easily removed from the grinding jig after processing, and the crystal wafer can be extremely removed. Even if it is processed thinly, it can be handled safely.

Next, the apparatus for manufacturing a quartz oscillator according to the present invention comprises:
A grinding jig for sucking and holding a quartz wafer, a grindstone having abrasive grains embedded in a conductive substrate, and an electrode member opposed to a surface portion of the grindstone that is not in contact with the quartz wafer at a predetermined interval. A power supply for applying a voltage between the grindstone and the electrode member, an electrolyte supply means for supplying an electrolytic solution between the grindstone and the electrode member, and a relative movement between the grindstone and the grinding jig. The crystal wafer can be ground by the grindstone by moving the crystal jig, the grinding jig, a support, attached to the support,
A holding member made of a porous material configured to receive an exhaust action from a surface portion other than the exposed surface portion,
The quartz wafer is configured to be able to be sucked and held on the exposed surface portion of the holding member by a suction force generated based on the exhausting action, and while the electroconductive action elutes the conductive base material from the grindstone to perform dressing. The crystal wafer is ground by electrolytic in-process dressing processing for processing the surface of the crystal wafer.

According to the present invention, the crystal wafer is stably and surely secured by holding the crystal wafer by suction on the exposed surface of the holding member made of a porous material and grinding it by electrolytic in-process dressing. Because it can be held and subjected to grinding, even if it is grinding,
Alternatively, even if the crystal wafer is processed to be extremely thin, the risk of breakage of the crystal wafer can be reduced. Also, by performing grinding while always sharpening the grindstone by electrolytic in-process dressing processing, even fine abrasive grains can be processed quickly, so there is no need to perform multi-stage polishing processing as in the conventional polishing method Also, it can be processed thinner than the conventional method.

In the present invention, an exhaust path for exhausting from the surface of the holding member other than the exposed surface portion is provided inside the support, and the exhaust of the holding member is performed by exhausting from the exhaust path. It is preferable that the apparatus be configured so that the wafer can be suction-held on the exposed surface.

In each of the above inventions, the porous material is preferably a sintered body using a granular material as a raw material. In this case, it is particularly desirable that the porous material is a ceramic.

In each of the above-mentioned inventions, it is particularly preferable that a flat surface having substantially the same height as the exposed surface is formed around the exposed surface of the holding member. On this flat surface,
It is desirable that the outer edge of the crystal wafer be configured to overlap (overlap). As a result, all of the exposed surface portion of the holding member can be sucked and held so as to be covered by the quartz wafer, so that the airtightness can be increased, so that the chucking force of the quartz wafer can be increased, and The outer edge can be reliably supported by the flat surface. In this case, in the support having a concave portion for accommodating the holding member, the flat surface is preferably formed on the upper surface of a frame-shaped portion formed around the concave portion.

In each of the above inventions, it is preferable that an opening is formed in the surface of the electrode member so that the electrolytic solution is supplied between the grindstone and the electrode member through the opening. In this case, it is desirable that a housing space for supplying the electrolytic solution is formed inside the electrode member. In this case, the electrolytic solution can be supplied so as to be ejected from the surface of the electrode member instead of being supplied only from the external supply nozzle or the like, so that the electrolytic solution can be supplied stably and uniformly. As a result, it is possible to uniformly and appropriately cause the electrolytic dressing action of the grindstone. As a result, the grinding speed can be improved and the surface roughness of the quartz wafer can be improved. In this case, it is particularly preferable to disperse and arrange a plurality of openings on the surface of the electrode member in order to further enhance the above-mentioned effect.

Each of the above-mentioned inventions relates to a quartz crystal wafer, but can be used for processing various kinds of wafers other than the quartz crystal wafer in the constitution of each invention. For example, a semiconductor wafer, a glass substrate, a ceramic substrate, or the like is used. Therefore, each of the above-mentioned inventions can also be considered as an invention applied to an arbitrary wafer other than the crystal wafer.

In the present application, a supporting member and a holding member made of a porous material attached to the supporting member and configured to receive an exhaust action from a surface portion other than the exposed surface portion are provided. There is also described an invention that includes a wafer grinding jig configured so that a wafer can be suction-held on the exposed surface portion of the holding member by a suction force generated based on an exhaust action. Furthermore, an invention in which any one of the above-mentioned claim 6 to claim 8 is added to this invention is also described. In each of these inventions, it is preferable that a flat surface having substantially the same height as the exposed surface is formed around the exposed surface of the holding member. The flat surface is desirably configured so that the outer edge of the quartz wafer overlaps (overlaps). Further, in this case, in the support provided with the concave portion for accommodating the holding member, it is preferable that the flat surface is formed on the upper surface of the frame portion formed around the concave portion.

[0023]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, embodiments of a method and an apparatus for manufacturing a crystal resonator according to the present invention will be described in detail. FIG. 1 shows grinding (grinding) used in the manufacturing method of the present embodiment.
FIG. 2 is a schematic schematic perspective view showing the structure of the device, and FIG. 2 is a schematic schematic sectional view of the device. In the present invention, the principle of the method for grinding a quartz wafer is so-called Electrolytic In-process Dreshing.
ssing) This is called processing. Details of this principle can be found in the RIKEN Symposium “Latest Trends in Mirror Grinding” March 5, 1991
On the day) and disclosed in JP-A-1-188266.

In this apparatus, the disk-shaped grinding wheel base 2 is configured to be rotatable about a rotating shaft 2a. A ring-shaped grindstone 4 is attached to one surface of the grindstone table 2. The grindstone 4 is a conductive grindstone in which abrasive grains are embedded in a conductive material as described later. A part of the grindstone 4 is disposed so as to overlap the turntable 6 in a plane, and the turntable 6 is configured to be rotatable around a rotation shaft 6a. A holding jig 10 described later is mounted and fixed on the surface of the turntable 6. Holding jig 1
A quartz wafer 20 is suction-held on the surface of the “0”.
The surface of the crystal wafer 20 comes into contact with the surface of the grinding wheel 4 and is subjected to grinding as described later. The rotation axes of the wheel head 2 and the turntable 6 are configured to be parallel to each other. The grinding device may be relatively moved while the grinding wheel 4 and the holding jig 10 are in contact with each other. The configuration described below allows the device configuration to be described below.

An electrode member 8 formed in an arc shape is opposed to a portion of the ring-shaped grindstone 4 not overlapping the turntable 6 in a plane, with a predetermined interval, that is, a gap d between the electrodes. Inside the conductive material, for example, the metal electrode member 8, there is formed a coolant accommodating portion 8a in which an electrolytic coolant EC which is a weakly conductive electrolytic solution and also serves as a coolant is supplied and temporarily accommodated. The coolant accommodating portion 8a is an internal space extending along the arc of the electrode member 8 in the same arc shape. The coolant accommodating portion 8a communicates with the opposing portion between the grindstone 4 and the surface of the electrode member 8 through a plurality of openings 8b formed on the surface of the electrode member 8. These openings 8b are formed in a substantially uniformly dispersed state on the surface of the electrode member 8. The electrode member 8 is fixed to the electrode mounting member 7 shown in FIG. A coolant supply path 7a connected to a coolant supply device (not shown) is formed in the electrode mounting member 7 (non-conductive material). The coolant supply passage 7a is opened inside the coolant accommodating portion 8a, and is configured such that the electrolytic coolant EC is supplied into the coolant accommodating portion 8a via the coolant supply passage 7a.
Electrolytic coolant EC supplied to coolant storage section 8a
Flows uniformly from the opening 8b into the gap between the electrodes.

Electrolytic coolant EC similar to that described above is supplied to the opposing portion between the grindstone 4 and the electrode member 8 from the side by a coolant supply nozzle 9. It is preferable that a plurality of coolant supply nozzles 9 are arranged along the extension direction of the electrode member 8 as shown in FIG. The electrolytic coolant is basically an electrolytic solution supplied between the grindstone 4 and the electrode member 8, but the same coolant is used.
It is desirable to supply also to the grinding part between the grindstone 4 and the crystal wafer 20 fixed on the holding jig 10. However,
Another coolant (such as one having only a cooling function) may be supplied to the grinding unit.

As shown in FIG. 2, the rotating shaft 2a of the grinding wheel head 2
Is formed with a cylindrical conductive connecting portion 2b having a surface having good electric contact properties. The power supply 14
A positive potential is applied through the power supply brush 15 pressed against the conductive connection portion 2b, and a negative potential is applied to the electrode member 8. The power supply 14 is a DC pulse power supply.

As the grinding wheel 4, diamond, CBN
Abrasive grains such as (tetragonal boron nitride) and various metal oxides are mixed with a conductive binder such as a metal bond (metal binder) and solidified, for example, sintered at a high temperature (1000 ° C. or higher). Can be used. As the metal bond, cast iron, bronze, nickel, cobalt, or the like can be used. Abrasive concentration (degree of concentration:
(JIS standard) is preferably about 50 to 200, and particularly preferably 50 to 100. The grain size of the abrasive grains is appropriately set according to the application. However, when hard abrasive grains such as diamond and CBN are used, when a mirror surface processing is required such as a quartz wafer, # 4000-
It is preferably about # 10000, and when using relatively soft abrasive grains other than the above, # 2000 to # 400
It is preferably about 0. The average particle size of # 4000 corresponds to about 4 μm.

In this device, the rotating shaft 2a and the rotating shaft 6a
Is rotated to grind the crystal wafer 20 fixed on the holding jig 10 by the grindstone 4. Also,
At the same time, the grindstone 4 is electrolyzed by the electrolytic coolant EC based on the electric power supplied from the power supply 14, so that the metal bond in the grindstone 4 is dissolved, and the abrasive grains embedded in the metal bond are exposed. When a current flows between the grindstone 4 and the electrode member 8 and the metal bond dissolves, the abrasive grains are exposed and so-called grindstone dressing is performed. A passivation film is formed, and the amount of current sharply decreases, and the elution of metal bonds also decreases. In this state, the grinding proceeds, and when the abrasive grains are worn by the grinding of the quartz wafer 20, the passive film is eventually broken through by the grinding action. When the passivation film is broken, a current flows again, the metal bond elutes into the electrolytic solution, and the abrasive grains again protrude onto the surface of the grindstone 4. By repeating such an operation, in the electrolytic in-process dressing process, the grinding proceeds while the dressing of the grindstone is always performed, so that clogging hardly occurs even when using abrasive grains having a fine particle size, The grinding can be performed efficiently, and the grinding can be performed quickly and in a stable state.

Next, the structure of a holding jig (wafer grinding jig) 10 for fixing a wafer used in the present apparatus will be described in detail. FIG. 3 is a longitudinal sectional view of a holding jig 10 for holding the crystal wafer 20 by suction, and FIG. 4 is a plan view of the holding jig 10.

A support 11 constituting the main body of the holding jig 10
Is formed of stainless steel or the like, and a rounded rectangular recess 11a is formed at the center of the upper surface. Recess 11a
Of the frame-like portion 11 slightly protruding from the outside
b. The frame portion 11b has substantially the same shape as the planar shape of the crystal wafer 20, and its inner edge is located inside the outer edge of the crystal wafer 20, and its outer edge is located outside the outer edge of the crystal wafer. Is formed. The surface (upper surface) of the frame 11b is processed flat. An exhaust path 11c is formed inside the recess 11a,
The exhaust path 11c includes an opening 11d that opens to the recess 11a. The opening 11d extends to the side from an internal position immediately below the recess 11a and opens to the side surface of the support 11.
e.

A plate-shaped holding plate 12 as a holding member is accommodated in the recess 11a, and is fixed in the recess 11a by a sealing and fixing material 13 made of an adhesive, glass, or the like. The holding plate 12 is made of a sintered body of ceramics such as alumina (Al ₂ O ₃ ) or other porous material. The porous material is preferably obtained by solidifying particles by a method such as sintering, and the particle size is appropriate. Specifically, the particle size is about 5 to 30 μm, and the bubble rate is 30 to 60%. Desirably. Actually, it has resistance to an electrolytic solution and the like, and furthermore, it has an exposed surface portion 12a (as shown in FIG. A sufficient suction force can be exerted on the exposed surface (upper surface), and the exposed surface 12
It is preferable that a substantially uniform suction force is generated over almost the entire surface of a. In particular, by using ceramics such as alumina or zirconia, sufficient chemical resistance and strength (rigidity) can be ensured. Further, the exposed surface portion 12a of the holding plate 12 accommodated in the concave portion 10a has the same height as the surface (upper surface) of the surrounding frame portion 11b, and
Preferably, it is formed flat.

Exhaust path 11 opened on the side of support 11
“c” is connected to an exhaust device (not shown), and sucks the holding plate 12 from the opening 11d. Exposed surface portion 12a of holding plate 12
When air is exhausted from the exhaust path 11c by the exhaust device with the crystal wafer 20 placed thereon, the crystal wafer 20 is sucked through the holding plate 12 and is sucked and held on the exposed surface portion 12a of the holding plate 12. You. At this time, the crystal wafer 2
It is preferable to set the dimensions of the holding jig 10 such that the outer edges of various wafers such as 0 overlap the flat surface of the frame-shaped portion 11b formed outside the holding plate 12.

FIG. 5 is an explanatory view showing a situation in which the quartz wafer 20 is sucked and held or removed from the holding jig 10. First, as shown in FIG. 5 (a), a liquid 16 such as water, alcohol, electrolytic coolant or other various kinds of coolant is attached to the exposed surface portion 12a of the holding plate 12, and the crystal The wafer 20 is placed on the exposed surface 12a. At this time, the crystal wafer 20 floats on the liquid 16.

Next, when the evacuation from the evacuation device (not shown) is started and the quartz wafer 20 is sucked from the evacuation path 11c, the liquid 16 is sucked into the holding plate 12 as shown in FIG. Depending on the amount of 16, a part thereof enters the exhaust passage 10 c through the opening 11 d. And
The crystal wafer 20 is also held by suction on the exposed surface portion 12 a of the holding plate 12 via the liquid 16. Here, the liquid 16
Is interposed between the quartz wafer 20 and the exposed surface portion 12a in a reduced pressure state, so that the airtightness between the quartz wafer 20 and the holding plate 12 is enhanced, and the attraction force of the quartz wafer 20 is increased. Further, since the liquid 16 is filled in the holding plate 12, the suction pressure of the holding plate 12 also increases the exposed surface portion 12a.
Are averaged over a number of regions. The holding plate 12
In order to sufficiently infiltrate the liquid 16 into the inside, a suction step for infiltrating the holding plate 12 with the liquid may be provided in advance. Furthermore, the viscosity of the liquid 16 is low enough to easily penetrate into the holding plate 12.
It is desirable to select a material having a viscosity that can be maintained within c.

When the quartz wafer 20 sucked and held on the exposed surface portion 12a of the holding plate 12 as described above is removed, the evacuation action from the evacuation path 11c is stopped, and the pressure in the evacuation path 11c is gradually reduced. Is raised toward the atmospheric pressure, the liquid 16 gradually exudes (leaches out) from the inside of the holding plate 12, so that the crystal wafer 20 exudes onto the exposed surface 12 a. It will be floating above. Therefore, crystal wafer 20 can be easily removed. In particular, when an extremely thin wafer such as a crystal wafer described later is used, the handling operation is difficult at the time of suction and removal of the wafer, particularly after processing, and there is a risk that breakage or other damage may occur. However, if the wafer is attached and detached by the above method,
Even thin and brittle wafers are safe and
It can be easily attached and detached.

The exposed surface portion 20 a is exposed through the liquid 16.
Since the wafer is sucked on the top, airtightness can be ensured even if there is some unevenness on the surface (lower surface) on the side where the wafer is sucked by the jig or on the exposed surface of the holding plate. As a result, the suction force can be increased, and a flat suction holding state can be obtained. Therefore, a separation accident during grinding can be prevented, and the flatness of the processed surface of the wafer can be improved.

A grinding test of the quartz wafer 20 was performed by performing the above-described electrolytic in-process dressing. Slicing a crystal lump to a thickness of about 260 μm,
A 32 mm square wafer was prepared, and the front and rear surfaces were roughly polished to form a thickness of about 200 μm, and the wafer was suction-held on the holding jig 10 and ground by the above-described apparatus. The grindstone used is formed by using diamond grains of # 4000 as abrasive grains, and setting the concentration of the abrasive grains to about 100 by metal bond of a mixture of cast iron and bronze.

As a result, the above-mentioned quartz wafer is finally
The thickness could be reduced to a thickness of μm. The surface of the crystal wafer after the grinding had a sufficient mirror surface. In addition, when the crystal wafer after grinding was removed from the holding jig by the method shown in FIG. 5, it could be easily removed without any problem. The processing of the quartz wafer having such a thickness is impossible at all by the conventional lapping processing, and the processing according to the present embodiment is essentially the grinding processing, and the dressing action of the grindstone always occurs. Therefore, a sufficient processing speed can be obtained. Further, there is an advantage that the processing can be performed without concern for a wafer crack or the like which may be caused by the lapping processing.

The method for manufacturing a crystal unit and the jig for grinding a wafer according to the present invention are not limited to the above-described examples, and various modifications can be made without departing from the gist of the present invention. Of course.

[0041]

As described above, according to the present invention,
By holding the quartz wafer by suction on the exposed surface of the holding member made of a porous material and grinding it by electrolytic in-process dressing, the quartz wafer is stably and
Since the wafer can be securely held and subjected to the grinding process, the risk of breakage of the quartz wafer can be reduced even when the grinding process is performed or the quartz wafer is processed to be extremely thin. Also, by performing grinding while always sharpening the grindstone by electrolytic in-process dressing processing, even fine abrasive grains can be processed quickly, so there is no need to perform multi-stage polishing processing as in the conventional polishing method Also, it can be processed thinner than the conventional method.

[Brief description of the drawings]

FIG. 1 is a schematic perspective view showing a schematic configuration of a grinding device in an embodiment of a method and an apparatus for manufacturing a quartz wafer according to the present invention.

FIG. 2 is a schematic cross-sectional view illustrating a schematic configuration of a grinding device according to the embodiment.

FIG. 3 is a longitudinal sectional view showing a structure of a holding jig of the grinding device in the embodiment.

FIG. 4 is a plan view showing the structure of the holding jig.

FIGS. 5A and 5B are state explanatory views showing a suction holding method using the holding jig. FIGS.

[Explanation of symbols]

 Reference Signs List 2 wheel head 4 wheel 6 turntable 7 electrode mounting member 8 electrode member 9 coolant supply nozzle 11 support 11 holding jig 11a recess 11b frame 11c exhaust path 12 holding plate 12a exposed surface 14 power supply 20 crystal wafer

Continued on the front page (72) Inventor Kenji Sakurai 3-3-5 Yamato, Suwa-shi, Nagano F-term in Seiko Epson Corporation (Reference) 3C043 BA09 BA16 BA18 BB06 CC04 DD02 DD05 DD06 EE02 3C047 AA25 AA31 3C049 AA04 AA09 AA19 AB04 AB09 AC04 CA01 CB01 CB02

Claims (8)

[Claims] A porous material, wherein a quartz wafer is attached to a grinding jig, and the grinding jig is attached to a support, and is configured to receive an exhaust action from a surface portion other than an exposed surface portion thereof. A holding member made of, and a state in which the quartz wafer is sucked and held on the exposed surface portion of the holding member by a suction force generated based on the exhaust action, and abrasive grains are embedded in the conductive base material. While the electrolytic solution is in contact with the surface of the grindstone, the conductive substrate is eluted by electrolytic action to perform dressing, while the quartz wafer and the quartz wafer are brought into contact with the surface of the grindstone on the surface of the quartz wafer. A method of manufacturing a crystal resonator, characterized in that a crystal wafer is ground by electrolytic in-process dressing processing for performing surface processing by relatively moving a grindstone. 2. The method according to claim 1, wherein the porous material is a sintered body using a granular material as a raw material. 3. The liquid crystal display device according to claim 1, wherein a liquid is arranged on the exposed surface of the holding member, and the quartz wafer is sucked and held by the exhaust action via the liquid. Manufacturing method of crystal oscillator. 4. The crystal wafer according to claim 1, wherein during the grinding process, the quartz wafer is sucked and held on the exposed surface portion by the exhaust action in a state where the liquid is filled in the inside of the holding member. A method for manufacturing a quartz oscillator. 5. A grinding jig for sucking and holding a quartz wafer, a grindstone having abrasive grains embedded in a conductive substrate, and a surface portion of the grindstone that is not in contact with the quartz wafer with a predetermined interval. An opposing electrode member, a power supply for applying a voltage between the grindstone and the electrode member, an electrolytic solution supply means for supplying an electrolytic solution between the grindstone and the electrode member, A driving unit configured to relatively move the jig and the grindstone so that the crystal wafer can be ground by the grindstone. The grinding jig includes a support, and an exposed surface attached to the support. A holding member made of a porous material configured to receive an exhausting action from a surface portion other than the portion, wherein the quartz wafer is placed on the exposed surface portion of the holding member by a suction force generated based on the exhausting action. Suction holding possible It is characterized in that the crystal wafer is ground by electrolytic in-process dressing processing in which the conductive substrate is eluted from the grindstone by electrolytic action and the surface processing of the crystal wafer is performed while performing dressing. Manufacturing equipment for quartz oscillators. 6. The holding member according to claim 5, further comprising an exhaust passage for exhausting from a surface portion of the holding member other than the exposed surface portion, wherein the holding member is evacuated from the exhaust passage. An apparatus for manufacturing a crystal unit, characterized in that a wafer can be held by suction on the exposed surface portion of a member. 7. An apparatus according to claim 5, wherein the porous material is a sintered body made of a granular material. 8. The apparatus according to claim 7, wherein the porous material is a ceramic.