WO2003095144A1

WO2003095144A1 - Lapping device and lapping work method

Info

Publication number: WO2003095144A1
Application number: PCT/JP2003/005843
Authority: WO
Inventors: Kazumasa Ohnishi
Original assignee: Kazumasa Ohnishi
Priority date: 2002-05-09
Filing date: 2003-05-09
Publication date: 2003-11-20
Also published as: AU2003235919A1; JPWO2003095144A1

Abstract

A lapping device characterized in that it includes a lapping machine (4), a slurry supplying device (10) for supplying abrasive slurry (11) to the surface of the lapping machine (4), a holder (22b) for an object to be lapped for holding an object (6) to be lapped while the object is brought into contact with the surface of the lapping machine (4) through the abrasive slurry (11), and linear movement drive devices (101a, 101b) attached to the lapping machine (4) and/or the holder (22b) for an object to be lapped. The lapping device is further characterized in that ultrasonic vibration applying means (12) for applying ultrasonic vibration vibrating in a direction perpendicular to the surface of the lapping machine (4) is attached to the lapping machine (4) and/or the holder (22b) for an object to be lapped, and the ultrasonic vibration applying means (12) is provided with electric energy supplying means (14). Using the lapping device reduces the consumption amount of abrasive, and enables lapping with higher accuracy than conventionally possible when slurry that contains abrasive having the same size as that of conventionally used abrasive is used.

Description

Description Wrapping apparatus and lapping processing method

[Technical field]

The present invention relates to a lap apparatus and a lap processing method used for high-precision polishing.

[Background technology]

As the integration density of integrated circuits typified by semiconductor memories increases, the height difference between the surface of the substrate used to form the integrated circuit and the height difference between the thin film elements and thin film wiring that constitute the integrated circuit must be reduced. A planarization technique is needed. If the height difference is large, the accuracy of the pattern jung performed in the manufacturing process of the integrated circuit decreases, and it becomes difficult to increase the integration density of the integrated circuit. A lapping device is a device that polishes the surface of an object to be polished, such as a substrate used for forming an integrated circuit, with high precision.

FIG. 1 is a front view showing a configuration example of a conventional lapping device, and FIG. 2 is a plan view of the lapping device of FIG. The lapping apparatus shown in FIGS. 1 and 2 includes a lapping machine 4 fixed to a rotating shaft 2 of a motor 1 via a support 3, and a slurry supply device 1 for supplying abrasive slurry 11 to the surface of the lapping machine 4. 0, and a disk-shaped polishing object holder 5 that rotatably holds the polishing object 6 while bringing the polishing object 6 into contact with the surface of the lapping machine 4 through an abrasive slurry.

The polishing object 6 is held (temporarily fixed) on the disk-shaped polishing object holder 5 using wax or the like. The disc-shaped polishing object holder 5 is supported by a pair of rollers 7a and 7b on its side surface. Each of the rollers 7a and 7b is rotatably supported by a roller support member 8 provided at an upper end of a support 9 erected on a base (not shown). The disk-shaped polishing object holder 5 rotates while being supported by the pair of rollers 7a and 7b as the lapping machine 4 rotates.

A slurry 14 containing abrasive grains is dripped from the slurry supply means 10 on the surface of the lapping machine 4. Is done. The abrasive slurry 11 is moved toward the object 6 to be polished with the rotation of the lapping machine 4, and is supplied between the lapping machine and the object to be polished.

The lapping machine 4 functions to temporarily hold the abrasive grains contained in the abrasive slurry 11 between the lapping machine 4 and the object 6 to be polished. The lapping machine 4 is made of a metal material (eg, tin) that is softer than the abrasive grains. For example, a lapping machine made of tin has its surface slightly depressed by the pressing of the abrasive grains, and temporarily holds the abrasive grains. Similarly, it is known to form the lapping machine from foamed resin or nonwoven fabric to temporarily hold the abrasive grains.

When each of the lapping machine 4 and the object 6 to be polished is rotated while a slurry containing abrasive grains is supplied between them, the surface of the object to be polished is polished. Polishing using such an abrasive slurry is called lapping force.

The type of the abrasive slurry is appropriately selected depending on the type of the object to be polished. As the abrasive particles contained in the abrasive slurry, alumina particles, silica particles, iron oxide particles, chromium oxide particles, diamond particles, and the like are used. As a solvent for the abrasive slurry, water or oil is used. It is also known that an acidic or alkaline solvent is used as a solvent for the abrasive slurry to chemically erode the surface of the object to be polished to assist polishing by the abrasive.

The polishing accuracy of a conventional lapping device differs depending on the configuration of the device and the type of abrasive slurry solvent, but is mainly determined by the size of the abrasive particles contained in the slurry. This is similar to the fact that when the object to be polished is polished with a sandpaper, the polishing accuracy is determined by the roughness of the sandpaper.

In addition to such a lapping device, a processing method for drilling or cutting a workpiece using ultrasonic waves is known. In this processing method, a tool that ultrasonically vibrates in a direction perpendicular to the surface of the processing object is pressed against the surface of the processing object via a solution containing abrasive grains. The energy of the ultrasonic vibration of the tool is applied to the abrasive grains. The workpiece is drilled or cut as the surface continues to be crushed by the impact of abrasive grains. There is also known a processing method in which a tool that ultrasonically vibrates in a direction parallel to the surface of the object to be processed is pressed against the surface of the object through a solution containing abrasive grains to polish the surface of the object. Have been. In this way, the surface of the workpiece contains abrasive grains A processing method of punching, cutting, or polishing an object to be processed by pressing a tool that vibrates ultrasonically through a solution is generally called an ultrasonic abrasive processing method. It is known that the surface roughness of an object after machining is mainly determined by the size of the abrasive grains in the ultrasonic abrasive grain machining method.

As described above, the polishing accuracy of the conventional lapping device is determined mainly by the size of the abrasive grains contained in the abrasive slurry. That is, in order to increase the polishing accuracy, it is necessary to use abrasive grains of smaller size. Generally, the smaller the size of the abrasive grains, the more expensive they are, and the higher the polishing accuracy, the higher the cost required for polishing.

In addition, in the conventional lapping machine, there is a problem that the object to be polished is not polished near the center of rotation of the lapping machine on the lapping machine surface. This is because the moving speed of the surface of the lapping machine is low near the rotation center, that is, the polishing speed is low. In a conventional lapping machine, it is necessary to supply abrasive slurry to the lapping machine surface near the center of rotation of the lapping machine, that is, to a region of the lapping machine surface that is not used for polishing. Supplying the abrasive slurry that is not used for polishing to such a region is one of the causes of the large use of the abrasive slurry in the conventional lapping device. The higher the amount of abrasive slurry used, the higher the cost of polishing.

An object of the present invention is to reduce the amount of abrasive slurry used, and to achieve polishing with higher precision than before when using a slurry containing abrasive grains of the same size. It is to provide a device.

[Disclosure of the Invention]

The present invention relates to a lapping machine, a slurry supply device for supplying abrasive slurry to the surface of the lapping machine, a polishing object holder for holding an object to be polished while contacting the surface of the lapping machine with the abrasive slurry, And a linear motion drive device attached to the lapping machine and / or the object holder for polishing, which linearly moves the lapping machine and / or the object holder to be polished in a direction along the surface of the lapping machine, With the ultrasonic vibration for applying ultrasonic vibration vibrating in a direction perpendicular to the surface of the lapping machine to the lapping machine and / or the object holder to be polished. And a means for supplying electric energy to the ultrasonic vibration applying means.

Preferred embodiments of the wrapping device of the present invention are as follows.

(1) A linear drive device is attached to each of the lapping machine and the workpiece holder.

The moving direction of the lapping machine and the moving direction of the object holder are perpendicular to each other.

(2) Only the holder for the object to be polished of the lapping device of (1) is provided with an ultrasonic vibration applying means for applying ultrasonic vibration oscillating in a direction perpendicular to the surface of the lapping machine.

(3) The ultrasonic vibration applying means of the lapping device of the above (2) is provided with another ultrasonic vibration applying means for applying ultrasonic vibration oscillating in the direction parallel to the surface of the lapping machine. The vibration applying means is also provided with a means for supplying electric energy.

(4) A linear drive is attached to the holder for the object to be polished, and a rotary drive is attached to the lapping machine to rotate the lapping machine around a direction perpendicular to the surface as a center axis.

(5) Each of the lapping machine and the object holder of the above (4) is provided with an ultrasonic vibration applying means for applying ultrasonic vibration oscillating in a direction perpendicular to the lapping machine surface. X

(6) The electric energy supply means of the ultrasonic vibration applying means has a mechanism for adjusting the voltage value or frequency value of the electric energy.

The present invention also provides a method for adjusting a voltage value or a frequency value of electric energy applied to an ultrasonic vibration applying means in accordance with the progress of polishing of a polishing object polished on a lapping machine surface using the lapping device. There is also a featured lapping method.

[Brief description of drawings]

FIG. 1 is a front view showing a configuration example of a conventional wrap device.

FIG. 2 is a plan view of the wrap device of FIG.

FIG. 3 is a perspective view showing a configuration example of the wrap device according to the present invention.

FIG. 4 is a cross-sectional view illustrating a polishing process using the lap device of FIG. FIG. 5 is a perspective view showing another configuration example of the wrapping device according to the present invention. FIG. 6 is a diagram for explaining the configuration of the ultrasonic vibration applying means of the lap device of FIG. FIG. 7 is a diagram showing still another configuration example of the wrapping device according to the present invention.

FIG. 8 is a diagram showing still another configuration example of the wrapping device according to the present invention.

[Detailed description of the invention]

The present invention will be described with reference to the accompanying drawings. FIG. 3 is a perspective view showing a configuration example of the wrapping device according to the present invention. The lapping machine shown in Fig. 3 is a lapping machine 4, a slurry supply device 10a for supplying abrasive slurry 11 to the surface of the lapping machine 4, a 10b, 10c, and a polishing object 6 for the lapping machine 4. The polishing object holder 2 2 b, which is held while being in contact with the surface of the workpiece via an abrasive slurry, and the lapping machine 4 and the polishing object holder, which are attached to the lapping machine 4 and the polishing object holder 22 b It is composed of linear drive devices 101 a, 101 b, etc. for moving 22 b one-dimensionally in the direction along the surface of the lapping machine 4. And, the polishing object holder 2 2b of the lapping apparatus shown in FIG. 3 is provided with ultrasonic vibration applying means 12 for applying ultrasonic vibration oscillating in the direction perpendicular to the surface of the lapping machine. The sonic vibration applying means 12 is provided with an electric energy supplying means 14.

The lapping machine 4 is joined to the base 20 via two linear guides 17a and 17b. With these two linear guides 17a and 17b, the lapping machine 4 can move in a one-dimensional direction (the length direction of the linear guide) along its surface. Slurry supply device 10a , 10b, and 10c are fixed to, for example, the end of the lapping machine 4 by a fixture (not shown). In Fig. 3, the illustration of piping and pumps connected to the slurry supply device is omitted.

The linear drive device 101a includes a rotary drive device 1a and a ball screw connected to a rotation shaft of the rotary drive device 1a. The ball screw is composed of a screw shaft 15a and a nut 16a. The ball screw converts the rotary motion of the rotary shaft of the rotary drive 1a into a linear motion of the nut 16a along the length of the screw shaft 15a. The rotation drive device la is fixed to the base 20 by a fixture (not shown). For example, a stepping motor is used as the rotation drive device 1a. Luck The linear drive device 101 a attached to the lapping board 4 moves the lapping board 4 one-dimensionally in a direction along the surface of the lapping board 4.

The configuration of the linear drive device 101b is the same as that of the linear drive device 101a. The rotary drive device lb is fixed to the base 20 by a fixture (not shown). A linear driving device 10 lb attached to the polishing object holder 2 2 b via the ultrasonic vibration applying means 12, the polishing object holder 2 2 b is moved along the surface of the lapping machine 4. Move one-dimensionally in the direction.

The linear drive device may be attached to at least one of the lapping machine and the holder for the object to be polished. By moving at least one of the lapping machine and the holder for the object to be polished one-dimensionally by the linear drive device, the entire surface of the lapping machine can be used for polishing. That is, in the lapping machine of the present invention, the entire surface of the lapping machine can be used for polishing, so that the surface area of the lapping machine can be set small. Therefore, the amount of slurry supplied for polishing (lapping) can be reduced.

As shown in FIG. 3, it is preferable that the linear drive device is attached to each of the lapping machine 4 and the workpiece holder 22b. Further, it is preferable that the moving direction of the lapping machine 4 and the moving direction of the object holder 22 b are perpendicular to each other. As described above, by attaching the linear drive device to each of the lapping machine 4 and the object holder 22b to be polished, it is not necessary to attach a rotary driving device to the lower side of the lapping machine as in the related art. The height of the wrapping device can be reduced. That is, the lapping device shown in FIG. 3 can be set to have a small surface area of the lapping machine as in the previous IH, and can be downsized because the height of the device is also small.

The ultrasonic vibration applying means 12 includes a piezoelectric vibrator having a configuration in which electrode plates 24 g and 24 h are attached to each surface of a disk-shaped piezoelectric ceramic 23 e, a support plate 25, and a disk. A piezoelectric vibrator having a configuration in which electrode plates 24 i and 24 j are attached to each surface of a piezoelectric ceramic 23 f is formed by an upper metal member 22 a and a lower metal member (the polishing object described above). A Langevin type vibrator composed of bolts sandwiched between 22b) is used.

Each of the piezoceramics 23e and 23f is polarized in its thickness direction . Each of the piezoelectric ceramics and the electrode plates attached to both sides thereof constitute a piezoelectric vibrator in a longitudinal vibration mode. These longitudinal mode piezoelectric vibrators function as ultrasonic vibration applying means for applying ultrasonic waves vibrating in the direction perpendicular to the surface of the lapping machine.

Each of the piezoelectric ceramics 23 e and 23 f is formed of, for example, a lead zirconate titanate-based ceramic material. Each of the electrode plates 24 g, 24 h, and 24 j is formed of, for example, phosphor bronze. Each of the upper metal member 22a, the support plate 25, and the lower metal member is formed of a metal material such as aluminum, for example.

As the electric energy supply means 14, for example, an AC power supply is used. When an AC voltage is supplied to the electrode plate of each piezoelectric vibrator by the electric energy supply means 14, each of the piezoelectric ceramics 23e and 23f is moved in a direction perpendicular to its surface, that is, a lapping machine. 4. Generates ultrasonic vibration that vibrates in the direction perpendicular to the surface. Thereby, the ultrasonic vibration applying means 12 applies the ultrasonic vibration vibrating in the direction perpendicular to the lapping machine 4 to the polishing object holder 22b.

The ultrasonic vibration applying means may be attached to at least one of the lapping machine and the holder for the object to be polished. Examples of the ultrasonic vibration applying means include an electrostrictive vibrator and a magnetostrictive vibrator. Examples of the electrostrictive vibrator include a piezoelectric vibrator in which electrodes are provided on each surface of a piezoelectric ceramic, and the Langevin type vibrator. Examples of the magnetostrictive vibrator include a metal magnetostrictive vibrator and a fly vibrator. As the ultrasonic vibration applying means, it is preferable to use an electrostrictive vibrator because of its simple structure. The ultrasonic vibration applying means is attached to the lapping machine (or the holder for the object to be polished) through a couplant such as grease or vaseline so as to efficiently transmit the ultrasonic wave to the lapping machine (or the holder for the object to be polished). It is preferable.

Next, a procedure for polishing an object to be polished using the lapping apparatus shown in FIG. 3 will be described. First, the polishing target 6 is held (temporarily fixed) in the polishing target holder 22b using wax or the like. Then, the rotary drive devices la and lb of the linear motion drive devices 101a and 101b are driven, and the lapping machine 4 and the polishing object holder 22b are respectively driven. Is moved one-dimensionally (reciprocating motion) in the direction along the surface of the lapping machine 4. At the same time, the abrasive slurry 11 is supplied to the surface of the lapping machine 4 from each of the slurry supply devices 10a, 10b, and 10c. At the same time, by applying an AC voltage (electric energy) to each of the piezoelectric vibrators of the ultrasonic vibration applying means 12 using the electric energy applying means 14, the lapping machine is attached to the object holder 22 for polishing. Ultrasonic vibration oscillating in the direction perpendicular to the surface of the object.

Along with the movement of the lapping machine 4 and the polishing object holder 2 2 b, the abrasive slurry 11 is supplied between the polishing object 6 and the lapping machine 4. The surface of the polishing target 6 is polished by the one-dimensional movement of the lapping machine 4 and the polishing target 6 held by the polishing target holder 2 2 b via the abrasive slurry. . In this polishing process, the surface of the polishing target 6 is polished with high accuracy by the ultrasonic vibration applied to the polishing object holder 22 b in a direction perpendicular to the surface of the lapping machine 4.

Next, the relationship between the polishing (lapping) using the lapping apparatus shown in FIG. 3 and the ultrasonic vibration applied to the object holder 22 b by the ultrasonic vibration applying means 12 will be described. FIG. 4 is a cross-sectional view illustrating a polishing process by the lapping device of FIG. In FIG. 4, in order to explain a state where the surface of the polishing target 6 is polished by the abrasive grains of the slurry, the abrasive grains 21 are described in a size larger than the actual size. The description of the abrasive slurry dissolution is omitted.

FIG. 4 (A) shows a state in which the surface of the object 6 is polished by the abrasive grains 21 when no ultrasonic vibration is applied to the object holder 22 b. Each of the lapping machine 4 and the polishing object 6 held by the polishing object holder 2 2 b is placed on the surface of the lapping machine 4 with a part of the abrasive grains 21 pressed into each surface. It is moving (reciprocating) one-dimensionally along it. Therefore, the surface of the polishing target 6 is polished by the abrasive grains 21. Since no ultrasonic vibration is applied to the object holder 2 2 b, the surface accuracy of the object 6 after polishing shows the same level of accuracy as when polishing using a conventional lapping device. .

FIG. 5B shows a state in which the surface of the object 6 is polished by the abrasive grains 21 when ultrasonic vibration is applied to the object holder 22b. Since the object to be polished 2 2 b is subjected to ultrasonic vibration, Ultrasonic vibration in the direction perpendicular to the plane. This ultrasonic vibration is transmitted to the polishing object 6, and the polishing object also ultrasonically vibrates in a direction perpendicular to the surface of the lapping machine 4. When the object 6 to be polished vibrates ultrasonically, the sound pressure of the ultrasonic wave emitted from the surface of the object 6 causes the gap between the lapping machine 4 and the object 6 to be slightly widened. Guessed. As shown in FIG. 5 (B), when the gap between the lapping machine 4 and the polishing target 6 is extremely slightly increased, the contact area between the polishing target 6 and the abrasive grains 21 is as shown in FIG. 5 (A). Will be smaller than. Therefore, the object to be polished 6 can be polished with high accuracy by the application of the ultrasonic vibration, similarly to the case where the object 6 to be polished is polished with the abrasive grains smaller in size than the abrasive grains 21.

FIG. 5 (C) shows that when the object to be polished 22 b is applied with an ultrasonic vibration larger than the ultrasonic vibration given in FIG. 6 shows a state in which the surface is polished. Since greater ultrasonic vibration is applied to the workpiece holder 22, the distance between the lapping machine 4 and the workpiece 6 is further increased, and the workpiece 6 contacts the abrasive grains 21. The area is smaller than in Fig. 5 (B). Therefore, the object 6 can be polished with higher accuracy.

As described above, the lapping device of the present invention can realize polishing with higher accuracy than that of the conventional lapping device when using a slurry containing abrasive grains of the same size. That is, when the surface of the object to be polished is polished with predetermined accuracy, abrasive grains having a size larger than that of the conventional lapping device can be used. As mentioned above, abrasives become more expensive as their size decreases. Therefore, by using the lapping device of the present invention, the cost required for polishing can be reduced.

Further, in the polishing using a conventional lapping device, there is a problem that when the solvent of the abrasive slurry is dried during the polishing, scratches are easily generated on the surface of the object to be polished. In the polishing process using the lapping device of the present invention, the contact area between the polishing object and the abrasive grains, that is, the friction between the polishing particles, is reduced by applying ultrasonic vibration to the polishing object holder. Therefore, it is also possible to reduce the occurrence of scratches on the surface of the object to be polished when the solvent of the abrasive slurry is dried during polishing.

In addition, as described above, the polishing accuracy of the conventional lapping device is mainly based on the abrasive grain. Determined by the size of the rally. Therefore, when the surface of the object to be polished is roughly polished and then polished using a conventional lapping device, it is necessary to replace the abrasive slurry. The lapping device of the present invention is capable of polishing objects to be polished with different precisions when polishing is performed without applying ultrasonic vibration to the object holder (or lapping machine), and when polishing is performed by applying ultrasonic waves. can do. By taking advantage of such features, first, the polishing object is roughly polished without applying ultrasonic vibration to the object holder, and then the ultrasonic vibration is applied to the object holder to obtain the abrasive grains to be used. The object to be polished can be finish-polished without replacing the slurry.

The electric energy supply means 14 provided in the ultrasonic vibration applying means of the lap device of the present invention includes a mechanism for adjusting the voltage value or the frequency value of the electric energy supplied to the ultrasonic vibration applying means 12. Preferably, it is provided.

By adjusting the voltage value or frequency value of the electric energy supplied to the ultrasonic vibration applying means 12, it is possible to adjust the magnitude of the ultrasonic vibration generated by the ultrasonic vibration applying means, that is, the precision of polishing. it can. The ultrasonic vibration applying means generates the largest ultrasonic vibration when the frequency value of the supplied electric energy (eg, AC voltage) matches the resonance frequency value of the ultrasonic vibration applying means. When the value is higher or lower than the resonance frequency, an ultrasonic vibration smaller than the above value is generated. Therefore, the polishing accuracy can also be adjusted by adjusting the frequency value of the electric energy.

The voltage value of the electric energy applied to the ultrasonic vibration applying means in accordance with the progress of the polishing of the object to be polished on the lapping machine surface using the lapping device provided with such electric energy supplying means. Alternatively, it is preferable to polish the object to be polished while adjusting the frequency. In other words, in the roughing stage, the object to be polished is polished without applying ultrasonic vibration to the lapping machine, and as the polishing progresses, gradually larger ultrasonic vibration is applied to make the object to be polished more accurate. By polishing with, the object to be polished can be polished efficiently.

The progress of the polishing can be detected, for example, from the magnitude of the friction between the lapping machine being polished and the object to be polished. As shown in Fig. 3, the ultrasonic vibration transducer support plate

0 1 b, a stress sensor for detecting the magnitude of the friction 18 and a stress measuring device 19 for converting an electric signal output from the stress sensor into a stress value (corresponding to the magnitude of the friction).

FIG. 5 is a perspective view showing another configuration example of the wrap device according to the present invention. FIG. 6 is a view for explaining the configuration of the ultrasonic vibration applying means of the wrapping device of FIG. The configuration of the lapping device of FIG. 5 is the same as that of FIG. 3 except that the configuration of the ultrasonic vibration applying means 12 is different.

As shown in FIG. 6 (A), the ultrasonic vibration applying means includes an electrode plate 24a, a piezoelectric ceramic 23a, an electrode plate 24b, a piezoelectric ceramic 23b, an electrode plate 24c, and a support. The plate 25, the electrode plate 24d, the piezoelectric ceramic 23c, the electrode plate 24e, the piezoelectric ceramic 23d, and the electrode plate 24f are connected to the upper metal member 22a and the lower metal member (as described above). A Langevin-type vibrator is used which is clamped between the object holder 22 and the object to be polished and bolted.

FIG. 6 (C) shows the configuration of each of the piezoelectric ceramics 23c and 23d and the polarization direction thereof. A disc-shaped piezoelectric ceramic is used for each of the piezoelectric ceramics 23c and 23d. The arrows in Fig. 6 (C) indicate the polarization direction of the piezoelectric ceramic. Each of the piezoelectric ceramics 23c and 23d and the electrode plates attached to both sides thereof constitute a piezoelectric vibrator in a longitudinal vibration mode. These longitudinal vibration mode piezoelectric vibrators function as ultrasonic vibration applying means for applying ultrasonic waves vibrating in a direction perpendicular to the surface of the lapping machine. These piezoelectric vibrators are provided with an AC power supply as electric energy supply means (Fig. 5: 14a). Each of the piezoelectric ceramics 23c and 23d vibrates in the thickness direction when an AC voltage (electric energy) is supplied through electrode plates attached to both surfaces thereof. Therefore, when the piezoelectric ceramics 23 c and 23 d vibrate, the ultrasonic vibration applying means 12 generates ultrasonic vibration vibrating in a direction perpendicular to the lapping machine surface, and this ultrasonic vibration is polished. Applied to the object holder 2 2 b. When the object to be polished 22 b is ultrasonically oscillated in a direction perpendicular to the surface of the lapping machine 4 by the application of the ultrasonic vibration, the surface of the object to be polished 6 is polished with high accuracy.

FIG. 6B shows the configuration of each of the piezoelectric ceramics 23a and 23b and the polarization direction thereof. Each of the piezoelectric ceramics 23a and 23b has four piezoelectric ceramics. Disc-shaped piezoelectric ceramics are used, which are bonded to each other with epoxy resin. The arrows in FIG. 6 (B) indicate the polarization direction of the piezoelectric ceramic. Each of the piezoelectric ceramics 23a and 23b and the electrode plates attached to both sides thereof constitute a torsional vibration mode piezoelectric vibrator. These torsional vibration mode piezoelectric vibrators function as ultrasonic vibration applying means for applying ultrasonic waves vibrating in a direction parallel to the surface of the lapping machine. These piezoelectric vibrators are provided with an AC power supply as an electric energy supply means (Fig. 5: 14b).

Each of the piezoelectric ceramics 23a and 23b vibrates in the circumferential direction when an AC voltage is supplied through electrode plates attached to both surfaces thereof. Therefore, when the piezoelectric ceramics 23a and 23b vibrate, the ultrasonic vibration applying means 12 generates ultrasonic vibrations vibrating in a direction parallel to the surface of the lapping board 4, and the ultrasonic vibrations Is attached to the polishing object holder 2 2 b. When the object holder 22 b is ultrasonically vibrated in a direction parallel to the surface of the lapping machine 4 by the application of the ultrasonic vibration, the surface of the object 6 is polished at a high speed. As described above, the ultrasonic vibration applying means 12 is provided with another ultrasonic vibration applying means (piezoelectric vibrator in the above-described torsional vibration mode) which vibrates in a direction parallel to the surface of the lapping machine 4. It is also preferred.

In addition to the above-described torsional vibration mode piezoelectric vibrator, for example, a bending vibration mode piezoelectric vibrator or a slip vibration mode A piezoelectric vibrator can be used.

FIG. 7 is a diagram showing still another configuration example of the wrapping device according to the present invention. The lapping machine 4 of the lapping machine shown in FIG. 7 is provided with a rotation drive device 1a for rotating the lapping machine 4 around a direction perpendicular to the surface as a center axis. The lapping machine 4 is connected to the rotating shaft 2 of the rotary drive. In the case of the lapping device shown in FIG. 7, an AC servomotor is used as the rotation driving device la.

The linear drive device 101b of the wrapping device shown in FIG. 7 includes a rotary drive device 1b and a ball screw connected to a rotation shaft of the rotary drive device 1b. The ball screw is composed of a screw shaft 15b and a nut 16b. The nut 16 b of the ball screw is connected to the support plate 25 of the ultrasonic vibration applying means 12. The rotary drive lb is fixed to a support standing upright on the base where the rotary drive 1a is installed ( The illustration is omitted). In the case of the lapping device shown in FIG. 7, a stepping motor is used as the rotary driving device 1b. The linear drive device 101 b attached to the workpiece holder 5 via the ultrasonic vibration applying means 1 2 moves the workpiece holder 5 one-dimensionally in a direction along the surface of the lapping machine 4. Move.

As in the case of the lapping apparatus shown in FIG. 7, the polishing apparatus has not been used for polishing by moving the holder 5 only one-dimensionally in the direction along the surface of the lapping machine. The vicinity of the center of rotation of the lapping machine on the surface of the lapping machine can be used for polishing. That is, since the entire surface of the lapping machine can be used for polishing, the area of the lapping machine surface (the diameter of the lapping machine) can be set small. Therefore, the amount of slurry supplied to the surface of the lapping machine can be reduced.

The polishing object holder 5 of the lapping apparatus shown in FIG. 7 is provided with ultrasonic vibration applying means 12 for applying ultrasonic vibration oscillating in a direction perpendicular to the surface of the lapping machine. The ultrasonic vibration applying means 12 is provided with an electric energy supply means 14b. Similarly, the lapping machine 4 is provided with ultrasonic vibration applying means 12a and 12b for applying ultrasonic vibration oscillating in a direction perpendicular to the surface of the lapping machine. The ultrasonic vibration applying means 12a and 12b are provided with electric energy supply means 14a. Each of the ultrasonic vibration applying means 12 a and 12 b and the electric energy supply means 14 a are electrically connected via a slip ring 13. In the lapping device of the present invention, as shown in FIG. 7, an ultrasonic vibration applying means can be added to each of the lapping machine and the holder for the object to be polished.

FIG. 8 is a diagram showing still another configuration example of the wrap device according to the present invention. The configuration of the lapping device shown in FIG. 8 is such that ultrasonic vibration applying means 12 c is attached to the side surface of the polishing object holder 5, and the polishing object holding tool 5 is connected to the polishing object holder 5 via the ultrasonic vibration applying means 12 c. It is the same as the wrap device of FIG. 7 except that a linear drive device 101 b is additionally provided. As the linear drive device 101b, a linear motor is used. The linear drive device 101b is fixed to a support erected on a base on which the rotary drive device 1a is installed (not shown).

Similarly to the above, the ultrasonic vibration applying means 12c is configured to connect the support plate 25 and the ultrasonic vibrators arranged on each surface of the support plate 25 to the upper metal member 22a and the lower metal member. Member 2 2 A Langevin type vibrator is used, which is constructed by tightening bolts while sandwiched between C and C. Another support plate 25c is fixed to the support plate 25 of the ultrasonic vibration applying means 12c via a support 25b. The linear drive device 101b is connected to the ultrasonic vibration applying means 12c via the support plate 25c.

In the lapping apparatus shown in FIG. 8, each of the ultrasonic vibration applying means 12a and 12b applies an ultrasonic vibration to the lapping machine 4 in a direction perpendicular to the surface of the lapping machine. By applying the ultrasonic vibration, the lapping machine 4 ultrasonically vibrates in a direction perpendicular to its surface, whereby the surface of the object 6 is polished with high accuracy. Then, the ultrasonic vibration applying means 12 c applies ultrasonic vibration to the polishing object holder 5 in a direction parallel to the surface of the lapping machine. When the object to be polished 5 is ultrasonically vibrated in a direction parallel to the surface of the lapping board 4 by the application of the ultrasonic vibration, the surface of the object to be polished 6 is polished at a high speed.

The configuration of the ultrasonic vibration applying means 12c of the wrapping device of FIG. 8 is the same as that of the ultrasonic vibration applying means 12 of FIG. That is, a piezoelectric vibrator in the longitudinal vibration mode is used as the ultrasonic vibrator included in the ultrasonic vibration applying means 12c. As shown in FIG. 8, the ultrasonic vibration applying means 12c provided with the piezoelectric vibrator in the longitudinal vibration mode applies ultrasonic vibration vibrating in the direction parallel to the surface of the lapping machine to the workpiece holder 5 to be polished. Give. As described above, a piezoelectric vibrator in a longitudinal vibration mode can be used as the ultrasonic vibration applying means for applying the ultrasonic vibration oscillating in the direction parallel to the surface of the lapping machine.

[Industrial applicability]

The lapping device of the present invention can realize polishing with higher precision than a conventional device when using a slurry containing abrasive grains of the same size by using ultrasonic vibration. Therefore, when polishing the surface of an object to be polished with a predetermined accuracy, the lapping device of the present invention uses a slurry containing abrasive grains having a larger size than that of the conventional device (a more inexpensive abrasive slurry). The polishing used can be performed. Further, in the lapping machine of the present invention, the entire surface of the lapping machine is used for polishing, so that the area of the lapping machine surface can be set small. Therefore, the amount of abrasive slurry supplied to the lapping machine surface of the lapping machine can be reduced. Therefore, using the wrapping device of the present invention By doing so, the cost required for polishing can be reduced.

Claims

The scope of the claims

1. A lapping machine, a slurry supply device for supplying an abrasive slurry to the surface of the lapping machine, a polishing object holder for holding an object to be polished while making contact with the surface of the lapping machine via the abrasive slurry, and A linear drive device attached to the lapping machine and the Z or the object holder to be polished, which linearly moves the lapping machine and / or the object holder to be polished one-dimensionally in a direction along the surface of the lapping machine; The lapping machine and / or the object holder to be polished are provided with ultrasonic vibration applying means for applying ultrasonic vibration oscillating in a direction perpendicular to the surface of the lapping machine. A wrapping device comprising:

2. The lapping device according to claim 1, wherein a linear drive device is attached to each of the lapping machine and the object holder, and a moving direction of the lapping machine and a moving direction of the object holder are orthogonal to each other. .

3. The lap apparatus according to claim 2, wherein the ultrasonic vibration applying means is provided only on the object holder to be polished.

4. The ultrasonic vibration applying means is provided with another ultrasonic vibration applying means for applying ultrasonic vibration vibrating in a direction parallel to the surface of the lapping machine, and the ultrasonic vibration applying means is also supplied with electric energy. 4. The wrapping device according to claim 3, wherein the wrapping device is provided.

5. A linear drive device is attached to the holder for the object to be polished, and a rotary drive device is attached to the lapping machine to rotate the lapping machine around a direction perpendicular to the surface as a center axis. A wrapping device according to claim 1.

6. The lap apparatus according to claim 5, wherein the ultrasonic vibration applying means is attached to each of the lapping machine and the holder for the object to be polished.

7. The wrapping device according to any one of claims 1 to 6, wherein the electric energy supply means of the ultrasonic vibration applying means has a mechanism for adjusting a voltage value or a frequency value of the electric energy.

8. The voltage value or frequency value of the electric energy applied to the ultrasonic vibration applying means in accordance with the progress of the polishing of the object to be polished on the lapping machine surface using the lapping device described in claim 7. Lap processing method, characterized in that the lap is adjusted.