JP2000042898A - Double-side polishing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To correct the polishing surfaces of an upper surface table and a lower surface table efficiently and automatically with simple constitution in a double-side polishing device provided with a carrier put in circular motion without rotation. SOLUTION: A double-side polishing device is provided with a carrier 12 with a through hole provided in a thin plate; an upper surface table 14 and a lower surface table 16 moved relatively to a wafer to polish it; carrier turning motion mechanism 20 putting the carrier 12 in circular motion without rotation and putting the wafer held between the upper surface table 14 and lower surface table 16, in turning motion in a through hole; an upper surface table elevating device 40 for elevating the upper surface table 14 so as to approach and separate from the carrier 12; a carrier elevating device 65 for elevating the carrier 12 so as to approach and separate from the lower surface table 16; a correcting means provided to advance/retreat between the upper surface table 14 and the carrier 12 so as to correct a polishing surface 14a of the lower surface table 14; and a correcting means provided to advance/retreat between the lower surface table 16 and the carrier 12 so as to correct a polishing surface 16a of the lower surface table 16.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a double-side polishing apparatus. Conventionally, as a double-side polishing apparatus, a processing material (hereinafter, referred to as a "work") is formed by rotating an external gear (hereinafter, referred to as an "external gear") and an internal gear (hereinafter, referred to as an "internal gear") at different angular velocities. The carrier corresponding to the planetary gear carrying the above-described carrier is rotated and revolved, and the upper and lower stools having polishing surfaces arranged above and below the carrier sandwich the work from above and below and relative to the work. There is one using a planetary gear mechanism that moves and grinds. This double-side polishing device is used as a lapping device (lapping machine) or polishing device. It has high accuracy and can simultaneously polish both surfaces, so that the processing time is short, and a thin material polishing process such as a silicon wafer used as a semiconductor chip material is completed. Suitable for.

[0002]

2. Description of the Related Art A configuration of a polishing apparatus using a conventional planetary gear mechanism will be described with reference to FIG. 112
Is an upper surface plate, and 114 is a lower surface plate. Each surface is provided with a polishing cloth (cloth), and a polishing surface is formed by the polishing cloth. 116 is an external gear, and 118 is an internal gear. Reference numeral 120 denotes a carrier. A work 121 is held in a through hole formed in the carrier 120, and rotates by meshing with an external gear 116 and an internal gear 118. The upper surface plate 112 is connected to the upper surface plate turning metal 112a,
The shaft 112 hanging from the upper platen driver 112a
A gear 112c is provided at the tip of b. Gear 112
c is the idle gear 112d,
d meshes with the gear 112e. This gear 112e
Is provided coaxially with the spindle 126 so as to rotate integrally with the spindle 126. The lower stool 114 is provided via a gear 114a provided coaxially with the lower stool 114,
It is connected to a gear 114 b provided coaxially with the spindle 126. The external gear 116 is connected to a transmission gear 116b provided coaxially with the spindle 126 via a gear 116a provided coaxially with the external gear 116. The internal gear 118 is connected to a transmission gear 118b provided coaxially with the spindle 126 via a gear 118a provided coaxially with the internal gear 118. That is, this polishing apparatus uses one driving device to drive the external gear 11.
6, a so-called four-way drive system in which the internal gear 118 and the upper and lower stools 112 and 114 are rotationally driven. Note that the spindle 126 is connected to a variable speed reducer 132, and the variable speed reducer 132 is connected to a motor 134 via a belt 136, and controls the rotation speed of the spindle 126.

According to the polishing apparatus using the planetary gear mechanism, for example, the gear 116a is set so that the angular velocity of the internal gear 118 becomes larger than the angular velocity of the external gear 116.
And the rotation ratio of the transmission gear 116b and the rotation ratio of the gear 118a and the transmission gear 118b, respectively.
The carrier 120 meshed between the external gear 116 and the internal gear 118 revolves in the same direction as the rotation direction of the internal gear 118 (for example, "counterclockwise") and rotates clockwise. The lower platen 114 also rotates counterclockwise, while the upper platen 112 rotates clockwise due to the presence of the idle gear 112d. Note that the rotation direction and rotation speed of the carrier 120 can be changed by setting the angular velocities of the external gear 116 and the internal gear 118 according to the polishing conditions.

[0004] In addition, the front and back polished surfaces of the workpiece 121 are
A liquid abrasive containing abrasive particles and the like is supplied, and the work of the liquid abrasive is suitably polished. In polishing a silicon wafer, an abrasive (generally called “slurry”) in which abrasive grains are dispersed in an alkaline polishing liquid is usually supplied between the silicon wafer and a polishing surface of a polishing platen to perform polishing. You. As a method of supplying a liquid abrasive, a liquid abrasive is dripped from above using a pump power and gravity through an abrasive supply hole provided vertically penetrating the upper platen 112. It is generally made to supply. The liquid abrasive discharged from the abrasive supply hole is supplied to a polishing section where the polishing surface of the upper platen 112 comes into contact with the work 121 and polishes the work 121, and is supplied between adjacent carriers 120. , And flows onto the polishing surface of the lower platen 114, and is supplied to a polishing section for polishing the work 121 by bringing the polishing surface of the lower platen 114 into contact with the work 121.

FIG. 9 is a plan view for explaining an example of the arrangement of the carriers 120 according to the polishing apparatus of FIG. 8, and there is a gap A between the adjacent carriers 120. This gap A exists in both the inner diameter portion and the outer diameter portion with a sufficient width, and the liquid abrasive is suitably supplied onto the polishing surface of the lower platen 114. As described above, the liquid abrasive is sufficiently supplied to both surfaces of the work 121 by a simple supply unit from above. According to this polishing apparatus, a liquid abrasive can be suitably supplied, and the carrier 120 can be moved in a complicated manner.
21 (for example, a silicon wafer) can be polished. Therefore, the flatness of the work can be improved. Also, the work 121
Can be simultaneously polished, so that the polishing efficiency can be improved.

However, in the double-side polishing apparatus using the above-mentioned conventional planetary gear mechanism, the carrier 120 is mounted on the external gear 11.
6 and the internal gear 118, it is difficult to cope with the recent increase in size of the work 121 such as a silicon wafer. That is, it is impossible to make the diameter of the carrier 120 larger than the radius of the surface plate, and the polished surface of the surface plate cannot be used efficiently. In addition, in a conventional double-side polishing apparatus using a planetary gear mechanism, a complicated gear mechanism is used, and it is difficult to increase the size of the apparatus. Costs increase in various aspects.

Therefore, the present applicant has developed the following double-side polishing apparatus as a background art. That is, the double-side polishing apparatus sandwiches a carrier formed of a thin flat plate with a through-hole and a wafer, which is a plate-shaped work arranged in the through-hole of the carrier, from above and below and at the same time relative to the wafer. A polishing machine, comprising: an upper surface plate and a lower surface plate for moving and polishing the carrier, wherein the carrier is caused to make a circular motion that does not rotate in a plane parallel to the surface of the carrier via a carrier holder, and A carrier swivel mechanism is provided for swiveling the wafer held between the upper and lower platens in the hole. In addition, the upper surface plate and the lower surface plate are each provided so as to perform a rotation (rotation).

In a double-side polishing apparatus provided with a carrier which does not rotate and has a circular motion as a background art, seasoning (correction) on the polished surfaces of an upper surface plate and a lower surface plate which comes in contact with a work and polishes the surface of the work. The following means can be considered. First, after the polishing step, the upper platen is raised, the carrier for polishing is removed, and a carrier 60 for correction is set as shown in FIG.
A correction ring 62 to be repaired by coming into contact with the polishing surfaces 14a and 16a of the upper and lower stools is inserted into the through hole 60a and held by the carrier 60 for correction. Then, the carrier 60 for correction is moved in the same manner as the carrier for polishing, so that the polishing surfaces 14a and 16a are corrected. The correction ring 62 is fitted and held in, for example, a large-diameter through hole 60a formed in the correction carrier 60,
A through hole 62a having a size corresponding to the diameter of the work 10 is formed in the inner peripheral portion.
Is formed in a ring shape having In addition, the correction ring 62 can be made of a brush having both sides formed of brushes, or made of glass, ceramics or the like. According to the correction ring 62 having brushes on both sides, it is possible to remove abrasive grains and polishing debris accumulated on both polishing surfaces 14a and 16a. Further, according to the repair ring 62 made of glass, ceramics, or the like, the two polished surfaces 14a and 16a, which have undergone the partial loss, can be repaired flat.

[0009]

However, the means for repairing the polished surface in the double-side polishing apparatus of the background art has a problem that it is difficult to efficiently automate the repair process. That is, in addition to replacing the polishing carrier and the repair carrier 60, the repair ring 62 must be further inserted into the through hole 60a, which is time-consuming and inefficient. Further, in order to automate the replacement process, a complicated mechanical device and its control device are required. In the prior art shown in FIGS. 8 and 9 as well, the polishing carrier 120 disposed between the large upper platen 112 and the lower platen 114 is replaced with a carrier for correction, and the upper platen is replaced. And the polishing surface of the lower platen is modified. Since the carrier for polishing and the carrier for repair are exchanged in this manner, it has been difficult to perform efficient automation for repairing the polished surface. Also, one motor 1
34, the upper platen 112 and the lower platen 11
4 and the connection between the carrier 120 and the drive mechanism is complicated, and the connection cannot be easily broken.

Accordingly, an object of the present invention is to provide a carrier having a circular motion that does not rotate, and a simple configuration that can efficiently and automatically correct the polished surfaces of the upper and lower stools. An object of the present invention is to provide a polishing apparatus.

[0011]

To achieve the above object, the present invention has the following arrangement. That is, the present invention
A carrier in which a thin plate is provided with a through-hole, an upper platen for sandwiching a plate-shaped work arranged in the through-hole of the carrier from above and below, and relatively moving and polishing the work; A lower platen, and a carrier that causes the carrier to make a circular motion that does not rotate in a plane parallel to the surface of the carrier, and that pivots the work held between the upper platen and the lower platen in the through hole. A swinging motion mechanism, an upper / lower plate moving device for moving the upper platen up and down so as to contact and separate the carrier, and a carrier raising and lowering device for moving the carrier up and down to move the lower platen up and down. Correction means provided between the upper surface plate and the carrier so as to be able to advance and retreat, and for correcting the polishing surface of the upper surface plate; and Correction means for correcting the surface. Double-sided polishing apparatus for the butterflies.

[0012] Further, the correction means is an injection nozzle which jets a brush and / or a pressure fluid and blows it to the polishing surface, so that it can be easily and suitably configured.

The upper platen and the lower platen are driven to rotate about an axis parallel to a direction perpendicular to the surface of the carrier, so that the work and the upper platen and the lower platen are relatively moved. The movement can be complicated and the polishing accuracy can be improved.

[0014] The carrier turning mechanism may further include a carrier holder for holding the carrier, and a holder-side shaft having an axis parallel to a direction perpendicular to a surface of the carrier and being axially mounted on the carrier holder. And a base-side shaft which is parallel to the holder-side shaft and is attached to the base at a predetermined distance from the base-side shaft, and the holder-side shaft is turned around the base-side shaft. It has a simple structure, but has a simple structure while holding the carrier holder with a crank member that makes a circular motion that does not rotate the carrier holder with respect to the base, and a drive device that rotates the crank member about an axis on the base side. It is possible to make the carried carrier make a circular motion that does not preferably rotate.

Also, a plurality of the crank members are provided,
The shafts on the base side are linked by a synchronization means such as a timing chain so that the plurality of crank members circularly move in synchronization with each other, so that the carrier can be suitably and stably moved with a simple configuration. it can.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings. FIG. 1 is an exploded perspective view schematically showing an embodiment of a basic configuration of a double-side polishing apparatus according to the present invention, and FIG. 2 shows a positional relationship of each configuration when the embodiment of FIG. 1 is operating. FIG. The present embodiment is a double-side polishing apparatus for polishing a silicon wafer 10 which is a plate-shaped work. The carrier 12 has a through-hole 12a formed in a thin flat plate, and is disposed in the through-hole of the carrier 12. An upper surface plate 14 and a lower surface plate 16 for sandwiching the wafer 10 from above and below and moving the wafer 10 relatively to the wafer 10 for polishing are provided. On each surface of the upper platen 14 and the lower platen 16, polishing cloths 14a,
6a, and a polishing surface is formed by the polishing cloths 14a and 16a. Further, the upper stool 14 and the lower stool 16 of the present embodiment are driven to rotate about an axis parallel to a direction orthogonal to the surface of the carrier 12. Wafer 10
Is circular and is loosely fitted in the circular through hole 12a,
In the through-hole 12a, it has a size that can rotate freely. The carrier 12 is generally formed of, for example, a glass epoxy plate, and is generally set to have a thickness of about 0.7 mm for the wafer 10 having a thickness of 0.8 mm.

Reference numeral 20 denotes a carrier rotating mechanism for moving the carrier 12 in a plane parallel to the plane of the carrier 12 and held between the upper platen 14 and the lower platen 16 in the through hole 12a. 1 is an example of a movement mechanism for moving a wafer 10 that has been moved. Carrier turning mechanism 20 in the present embodiment
Causes the carrier 12 to make a circular motion that does not rotate in a plane parallel to the plane of the carrier 12, and to pivotally move the wafer 10 held in the through-hole 12 a and sandwiched by the upper platen 14 and the lower platen 16. Let it. That is, when the thickness of the carrier 12 is not considered, the carrier 12 is caused to make a circular motion that does not rotate in the same plane as the plane of the carrier 12. The specific configuration of the carrier turning mechanism 20 will be described below.

A carrier holder 22 is formed in a ring shape and holds the carrier 12. Here, the connecting means 50 for connecting the carrier 12 and the carrier holder 22 will be described. FIGS. 3A and 3B are explanatory views (FIG. 3A is a plan view and FIG. 4B is a cross-sectional view) illustrating the overall configuration of an example of the carrier 12 and the carrier holder 22, and FIG. It is a principal part expanded sectional view. The linking means 50 connects the carrier 12 with the carrier 1
2 is held by being connected to a carrier holder 22 so that the carrier 2 does not rotate and absorbs the elongation of the carrier 12 due to thermal expansion. Connecting means 50 of the present embodiment
Then, as shown in FIG. 4, a pin 23 provided on the carrier holder 22 side and the carrier 1 for loosely fitting the pin 23 are provided.
2 is provided with a hole 12b provided with a clearance in a direction in which the carrier 12 expands due to thermal expansion (in this embodiment, a radial direction of the circular carrier 12). The clearance of the hole 12b may be suitably provided at least in a direction in which the carrier 12 expands due to thermal expansion.
What is necessary is just to be formed in a long hole.

In this embodiment, the carrier 12
The inner peripheral surface 22a of the carrier holder 22 is arranged so that the outer peripheral edge thereof can be suitably slid when thermally expanded.
Is formed so as to generate a clearance between the first and second members.
That is, the outer diameter of the carrier 12 is smaller than the inner diameter of the inner peripheral surface 22a by a predetermined dimension. The hole 12b of the carrier 12, which is provided with a clearance in consideration of the thermal expansion of the carrier 12 as described above, is directly set by being fitted to the pin 23 of the carrier holder 22. By providing the connecting means 50 for absorbing the expansion of the carrier 12 due to the thermal expansion, the carrier 12 can be suitably connected to the carrier holder 22 with a simple configuration in a state where the carrier 12 is prevented from rotating. Thereby, the elongation of the carrier 12 can be suitably released and absorbed, and the deformation of the carrier 12 can be prevented. Further, since the carrier 12 is configured to be mounted by being fitted to the carrier holder 22, the operation at the time of mounting is simplified.

Next, the function of adjusting the height of the carrier 12 provided in the carrier holder 22 will be described. 23a
Is a flange portion, which is integrally provided in the middle of the pin 23 in a washer shape. This flange portion 23a
The supporting portion is provided on the carrier holder 22 side and directly supports the carrier 12 to hold it. Pin 2
A screw 23b is provided below the third flange 23a so that the pin 23 can be attached to the lower step 22b of the carrier holder 22.
Is provided. The height of the flange portion 23a can be adjusted by adjusting the degree of screwing of the screw portion 23b into the lower portion 22b of the carrier holder 22. By providing the flange portion 23a in this manner, the height position of the carrier 12 can be suitably adjusted, and the carrier 12 can be appropriately held by the carrier holder 22.

That is, by adjusting the height of the flange portion 23a, it is possible to suitably cope with a change in conditions, such as when the polishing pad 16a of the lower platen 16 is worn out and becomes thin.
At about the same height as the surface of the polishing pad 16a of No. 6, the carrier 12 can be suitably held so as not to be bent. Accordingly, the carrier 12 can be suitably held horizontally, and cracking of the wafer 10 and deterioration of polishing accuracy can be prevented. Further, the outer peripheral surface of the carrier 12 is partially received by the surface of the flange portion 23a, and the carrier 1
2 can be suitably supported by sliding due to expansion and contraction. That is, since the contact area between the outer peripheral surface (lower surface) of the carrier 12 and the upper surface on the side of the carrier holder 22 can be reduced, the sliding friction resistance can be reduced, and the carrier 12 can slide favorably. Thereby, the expansion and contraction force of the carrier 12 due to heat or the like is suitably released, and the occurrence of distortion of the carrier 12 can be prevented.

In the above embodiment, the support height of the carrier 12 is adjusted by adjusting the height of the flange portion 23a of the pin 23. However, the present invention is not limited to this. The configuration is not particularly limited as long as it is a suitable means capable of supporting the 12 at a predetermined height.
For example, a mechanism for raising and lowering the carrier holder 22 itself may be provided, and the supporting portion for supporting the carrier 12 may be basically the upper surface of the lower portion 22b of the carrier holder 22. The upper surface of the lower portion 22b may be provided with irregularities in order to improve the slipperiness.

Next, another linking means according to the present invention will be described with reference to FIG. FIG. 5A is a plan view,
FIG. 5B is a sectional view. As is apparent from the drawing, this embodiment differs from the above embodiment only in the linking means 50. The linking means 50 includes an internal gear-shaped engaged portion 52 provided on the carrier holder 22 side, and An external gear-shaped engaging portion 42 is provided on the carrier 12 so as to engage with the engaged portion 52 with play. That is, the gear provided on the outer periphery of the carrier 12 and the gear provided on the inner periphery of the ring-shaped carrier holder 22 are engaged with play with play. This also makes it possible to suitably connect the carrier 12 to the carrier holder 22 with a simple configuration. And the same effect as the above embodiment can be obtained.

Next, an embodiment of each structure of the carrier turning mechanism 20 will be described with reference to FIGS. Reference numeral 24 denotes a crank member, which has an axis parallel to the axis L of the upper stool 14 and the lower stool 16, and a shaft 24 a on the holder side which is mounted on the carrier holder 22, and a shaft center on the shaft 24 a on the holder side. Are provided with a base-side shaft 24b which is parallel and is attached to the base 30 (see FIG. 2) at a predetermined distance. That is, it is formed to have the same function as the crank arm of the crank mechanism. In the present embodiment, the crank members 24 are arranged at four positions between the base 30 and the carrier holder 22, support the carrier holder 22, and rotate the holder-side shaft 24a about the base-side shaft 24b. This causes the carrier holder 22 to make a circular motion that does not rotate with respect to the base 30. The holder-side shaft 24a is rotatably inserted into a bearing portion 22c provided on the outer peripheral surface of the carrier holder 22 so as to protrude therefrom, and is mounted on the shaft. Thereby, the carrier 1
Numeral 2 is eccentric M from the axis L of the upper surface plate 14 and the lower surface plate 16 and turns (circular motion that does not rotate). The radius of the revolving circular motion is the same as the distance between the shaft 24a on the holder side and the shaft 24b on the base side (distance of the eccentricity M), and all points of the carrier 12 draw the same small circle locus. Become.

Reference numeral 28 denotes a timing chain,
Each crank member 24 is wound around a sprocket 25 (four in this embodiment) fixed coaxially to a shaft 24 b on the base side of each crank member 24. The timing chain 28 and the four sprockets 25 constitute a synchronizing means for connecting and synchronizing the four base shafts 24b so that the four crank members 24 make a circular motion in synchronization. This synchronizing means has a simple configuration, and allows the carrier 12 to move favorably and stably. As a result, the polishing accuracy can be improved, and the flatness of the wafer can be improved. Incidentally, the synchronizing means is not limited to the present embodiment, and it is a matter of course that a timing belt or a gear may be used. Three
Reference numeral 2 denotes a motor (for example, a gear motor), and reference numeral 34 denotes an output gear fixed to an output shaft. The output gear 34 meshes with a gear 26 fixed coaxially to a shaft 24 b of the crank member 24 on the base side. Thereby, the crank member 2
A rotation driving device is configured to rotate the rotation shaft 4 around a shaft 24b on the base side.

It should be noted that a plurality of motors (for example, electric motors) arranged corresponding to the respective crank members 24 can be used as the rotary drive device. In the case of an electric motor, the plurality of crank members 24 can be synchronously moved by electrically synchronizing, and the carrier 12 can be smoothly moved. In this embodiment, the case where four crank members 24 are provided has been described. However, the present invention is not limited to this, and the carrier holder 22 can be suitably supported if at least three crank members 24 are provided. . Further, by combining linear motions of two orthogonal axes, 2
A moving body of an XY table capable of obtaining a dimensional motion;
If the carrier holder 22 and the carrier holder 22 can be moved integrally, by driving one crank member 24,
The carrier holder 22 can be moved in a circular motion without rotating. That is, the moving body makes a non-rotational movement by being guided by the guides extending in two orthogonal axes of the XY table, and the movement of the moving body is converted into a movement of the carrier holder 22 (a circular movement that does not rotate). It can be suitably used. Also, without using the crank member 24 at all, X
You may make it provide a drive means in the Y table itself.
That is, an X-axis and a Y-axis composed of a combination of a servomotor and a ball screw, or a servomotor and a timing chain, for directly driving the X-axis and Y-axis members, respectively
By using a shaft driving mechanism, the carrier holder 22 integrated with the moving body may be moved (circular movement that does not rotate). In this case, at least two motors are used. By controlling the motors, various two-dimensional motions that do not rotate can be obtained in addition to the turning circular motion. Available to

A lower platen rotating motor 36 is a power unit for rotating the lower platen 16 on its own axis. For example, as in the present embodiment, a geared motor can be used, and its output shaft may be directly connected to the rotation shaft of the lower stool 16. Reference numeral 38 denotes a power means for rotating the upper stool, which rotates the upper stool 14 on its own axis.
Lower platen rotating motor 36 and upper platen rotating power means 38
Can flexibly cope with various polishing specifications as long as the rotation direction and the rotation speed can be freely changed. In this double-side polishing apparatus, the wafer 10 arranged in the through-hole 12a of the carrier 12 is sandwiched between an upper platen 14 and a lower platen 16 as shown in FIG. 2, and the wafer is polished. . At this time, the force for clamping the wafer 10 is mainly due to the pressing means provided on the upper surface plate 14 side. For example, by using air pressure, the maximum pressing force is the weight of the upper platen 14, and the pressing force of the upper platen 14 against the wafer 10 is reduced by increasing the air pressure to reduce the pressing force. May be adjusted. In this airbag system, the pressure can be suitably and easily adjusted by controlling the air pressure. In addition to the pressing means, an elevating device 40 for moving the upper stool 14 up and down is provided on the upper stool 14 side, and operates when the wafer 10 is supplied and ejected.

Next, regarding the supply means of the liquid abrasive,
A description will be given based on FIG. 1 and FIG. The upper surface plate 14 has an abrasive supply hole 14b for supplying a slurry (liquid abrasive) to a polishing portion where the polishing surface 14a of the upper surface plate 14 contacts the wafer 10 to polish the wafer 10. Is provided. The holes 14b for supplying the abrasive are provided in the wafer 10
It is sufficient that a liquid abrasive can be sufficiently and uniformly supplied to the polishing section, and it is appropriately provided in such a size as not to adversely affect the polishing, and the form and the number thereof are not particularly limited. In addition, the hole 14b for supplying the abrasive in the present embodiment is
A total of 21 pieces are arranged in a matrix so as to be distributed at equal density on the upper surface plate 14, and each is provided with a small diameter. In addition, the hole 14b for supplying the abrasive in the present embodiment.
Are provided to penetrate the upper surface plate 14 in the up-down direction.
Although not shown, a tube or the like is connected to the upper end of the abrasive supply hole 14b so that the liquid abrasive pumped by a pump or the like is appropriately distributed and supplied. .

Then, the liquid abrasive supplied from the abrasive supply hole 14b is passed through the carrier 12 so that the polishing surface 16a of the lower platen (lower platen 16) comes into contact with the wafer 10 so that the wafer 10 comes into contact therewith. A communication hole 15 for supplying a liquid polishing liquid is provided to a polishing section for polishing the wafer 10. This communication hole 15 may be provided in a suitable form at a position that does not affect the strength of the carrier 12, and the size, shape, or number thereof is not limited. In the embodiment shown in FIG. 3, the center of the carrier 12 and the carrier 1
2 between the adjacent through holes 12a in the circumferential direction,
A plurality of circular communication holes 15 are formed.

According to the carrier 12, the liquid polishing liquid can be suitably supplied to both surfaces of the wafer 10 to be polished, and the polishing can be suitably performed. That is, the communication hole 1, which is a hole formed in the carrier 12,
5, and can sufficiently flow into the back surface of the wafer 10 (the surface in contact with the polishing surface 16a). For this reason, the polishing conditions can be uniformly and suitably maintained, and both surfaces of the wafer 10 can be accurately polished. The liquid polishing liquid supplied onto the polishing surface 16a sequentially overflows from the polishing surface 16a in the outer peripheral direction and is discharged, and is further collected and circulated as appropriate, as in the case of the conventional double-side polishing apparatus. .

As shown in FIG. 1, reference numeral 62 denotes a roller, which is an anti-vibration means for abutting against the upper stool 14 to prevent the upper stool 14 from swinging in a direction parallel to the surface of the carrier 12. This is an example. The roller 62 may be attached to the upper surface plate 14 as appropriate.
The upper surface plate 14 on the base 30 is brought into contact with the outer periphery 14c of
It is rotatably mounted on a guide roller body (not shown) provided in the vicinity. By sandwiching the upper surface plate 14 when the polishing process is performed by the plurality of rollers 62,
The movement of the upper stool 14 in a direction parallel to the surface of the carrier 12 can be restricted to prevent vibration.

Next, an embodiment of the correcting means which is a characteristic configuration of the present invention will be described with reference to FIG. The present embodiment is a correcting means for seasoning (correcting) the polished surfaces of the upper lapping plate 14 and the lower lapping plate 16 which come into contact with the wafer 10 as a work and polish the surface of the wafer. FIG.
FIG. 6A is a plan view for explaining the operation of the correcting means, and FIG.
(B) is a side view explaining the positional relationship of the correction means.
In addition, about the same structure as the Example demonstrated above,
The same reference numerals are given and the description is omitted. Numeral 40 denotes an elevating device for the upper stool, which raises and lowers the upper stool 14 such that the upper stool 14 is brought into and away from the carrier 12. Numeral 65 denotes a carrier lifting / lowering device which raises / lowers the carrier 12 so as to contact / separate from the lower platen 16. In the present embodiment, the carrier holder 22
Can be moved up and down, and the carrier 12 is lifted when correction is performed by brushing or the like, and a space is provided between the lower platen 16 and the carrier 12 at a predetermined interval. In addition, each of the lifting / lowering means 40,
As the 65, a known cylinder device or a reciprocating device such as a motion mechanism including a known linear motion guide, a ball screw, and an electric motor may be used.

Reference numeral 66 denotes a correction means for the upper surface plate, which is provided between the upper surface plate 14 and the carrier 12 so as to be able to advance and retreat, and corrects the polishing surface 14a of the upper surface plate 14. Reference numeral 68 denotes a correction means for the lower stool, which is provided between the lower stool 16 and the carrier 12 so as to advance and retreat, and corrects the polishing surface 16a of the lower stool 16. As each of the correcting means 66 and 68 described above, for example, a spray nozzle that sprays a brush and / or a pressure fluid and blows the polishing surface can be used. When sharing the brush and the injection nozzle, provide a brush part around the injection nozzle,
The pressure fluid may be ejected inside the brush portion. With this configuration, the brush portion
The pressure fluid discharged from the injection nozzle can be prevented from being scattered and allowed to flow out. Note that the pressure fluid is a fluid in which a liquid such as water or a gas such as air is made to have a high pressure. For example, a fluid in which water having high cleanliness is made to have a high pressure may be used. According to this pressure fluid, the polishing surfaces 14a, 1
The abrasive grains and the like attached to 6a can be blown off and removed.

Each correction means 66 of the embodiment shown in FIG.
68 is assumed to be in contact with each of the polishing surfaces 14a and 16a for correction, and 67 is a correction member. The correcting member 67 may be a member having a brush in contact with the polishing surface, or a member made of glass, ceramics, or the like. Correction member 6 whose contact surface is a brush
According to 7, it is possible to remove abrasive grains and polishing debris accumulated on both polishing surfaces 14a and 16a made of a polishing cloth. In addition, according to the correction member 67 made of glass, ceramics, or the like, the two polishing surfaces 14a and 16a in which the one-sided reduction has occurred can be corrected flat. In the case of the correction member 67 made of glass, ceramics, or the like, by using a member whose surface is appropriately roughened such as a porous surface, the polishing surfaces 14a, 16a
Can be corrected efficiently. In addition, suction can be used as a correction means for adjusting the polishing surfaces 14a and 16a. In combination with the correction member 67, the deposited abrasive grains and polishing debris may be suctioned and removed.

Reference numeral 69 denotes a rotating arm, which is provided on each of the correcting means 66, 68, and which fixes each of the correcting members 67, 67 of the brush (or other seasoning tool) by a solid line and a two-dot chain line in FIG. Swing as shown by. That is,
Each of the rotating arms 69, 69 rotates about a rotating shaft 69a provided on the base, and moves each of the correction members 67, 67 in the radial direction of the upper stool 14 and the lower stool 16. 69b
Reference numeral denotes a swing motor, which is a driving device that swings and swings the rotating arm 69. As described above, the upper arm 14 and the lower arm 16 are individually brushed (corrected) by rotating the rotating arms 69 and 69 and rotating the upper arm 14 and the lower arm 16. The correction member 67 is moved only within a predetermined range by the rotation arm 69, but since the upper stool 14 and the lower stool 16 are rotated, the entire polishing surfaces 14a and 16a can be corrected.

Thus, the polishing surfaces 14a and 16a can be efficiently corrected by the correction means 66 and 68 having the correction members 67 such as brushes without removing the polishing carrier 12. In addition, a complicated mechanical configuration such as a robot device and a control means are not required, and the correction process such as brushing can be efficiently automated. As a result, the entire polishing apparatus system can be automated. Note that the prior art carrier 120 shown in FIGS. 8 and 9 has an external gear 116 and an internal gear 118 that rotate in a horizontal plane.
However, it is difficult to move the carrier 120 up and down, and it is difficult to modify the polished surface as in the present embodiment.

Next, an example of a method for using the double-side polishing apparatus according to the present invention will be described. First, a case will be described in which the upper stool 14 and the lower stool 16 are rotated in the same direction but in opposite directions without moving the carrier 12. That is, as shown in FIG.
4 rotates clockwise, and the lower platen 16 rotates counterclockwise.
In this case, since the frictional forces act in completely opposite directions, the kinetic forces cancel each other out, and theoretically the wafer 10
The polishing is performed on both sides in the stopped state. However, in this case, the peripheral speed of the upper surface plate 14 and the lower surface plate 16 becomes larger toward the outer periphery. Therefore, the wafer 10
Polishing is promoted in a portion farther from the portion corresponding to the axis L of the upper platen 14 and the lower platen 16, so that the wafer 10 is not uniformly polished.

Next, a description will be given of a polishing action by causing the carrier 12 to make a circular motion without rotating by the motion mechanism having the above-described structure. If only the non-rotating circular motion of the carrier 12 is considered without considering the rotation of the upper stool 14 and the lower stool 16, according to the non-rotating circular motion, at all points of the moving member (carrier 12), The same exercise will be done. This is a kind of oscillating motion in the sense that all points are the same motion, and it can be considered that the trajectory of the oscillating motion is a circle. Therefore, if the wafer 10 is swiveled through the carrier 12 which does not rotate and moves in a circular motion, both surfaces of the wafer 10 are uniformly polished if the action by this motion is limited.

When the rotating motion of the upper and lower stools 14 and 16 and the circular motion of the carrier 12 without rotation are simultaneously operated, the wafer 10 is rotatably held in the through hole 12a. Therefore, in particular, the upper surface plate 14 and the lower surface plate 16
When the absolute value of the rotation speed of the base plate is different (when the rotation speed of the other base plate is increased with respect to one base plate), the wafer 10 is moved in the rotation direction of the base plate having the higher rotation speed. Go around. That is, the wafer 10 rotates in a predetermined direction. In this way, the rotation of the wafer 10 causes the peripheral speed of the upper and lower stools 14 and 16 to increase toward the outer periphery thereof. However, the influence can be eliminated and the wafer 10 can be uniformly polished. it can. In order to uniformly polish both surfaces of the wafer 10, the upper platen 14 and the lower platen 16 may be alternately rotated so that one of them becomes faster.

Next, another example of the method of using the double-side polishing apparatus according to the present invention will be described. In the above embodiment, a plurality of through holes 12a are provided, and a plurality of workpieces (wafer 1) are provided.
In the present invention, the polishing is performed simultaneously. However, the present invention is not limited to this. For example, the carrier 12 is provided with only one through hole 12a for holding a large work, and the polishing is performed on both sides of the large work. It can also be used as a device.
In addition, as a large-sized work, there is a work such as a rectangular glass plate used for liquid crystal, or a wafer (circular) processed by a single wafer. In this case, the large workpiece is the carrier 1
2 is arranged almost entirely from the center to the vicinity of the periphery. At this time, the polishing is performed mainly by using the circular motion of the carrier 12 that does not rotate, and the rotation speed of the upper stool 14 and the lower stool 16 is reduced to such a degree that uneven polishing does not occur. And it can grind suitably. That is, in the upper stool 14 and the lower stool 16, the polishing action becomes larger toward the outer periphery due to the difference in the peripheral speed.
If the rotation speed is much slower than the non-rotating circular motion of the carrier 12, it is possible to make the polishing operation hardly directly involved. The rotation of the upper platen 14 and the lower platen 16 constantly updates the surface of the platen in contact with the work and improves the polishing action, for example, by supplying a liquid abrasive to the entire surface of the work evenly. Indirectly, it can suitably contribute.

In the above embodiment, the polishing apparatus has been described, but the present invention can be suitably applied to a lapping apparatus. As described above, the present invention has been described variously with reference to preferred embodiments. However, the present invention is not limited to the embodiments, and it is needless to say that many modifications can be made without departing from the spirit of the invention. That is.

[0042]

According to the double-side polishing apparatus of the present invention, the upper platen and the carrier that does not rotate and move in a circular motion are raised and lowered.
The polishing surface of the upper platen is corrected by the correcting means provided to be able to advance and retreat between the upper surface plate and the carrier, and the polishing surface of the lower surface plate is corrected by the correcting means provided to be able to advance and retreat between the lower surface plate and the carrier. In order to perform the correction, it is possible to suitably perform the correction of each polished surface without removing the carrier. Therefore, according to the present invention, the respective polishing surfaces of the upper stool and the lower stool can be efficiently corrected automatically with a simple configuration.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view of an embodiment of a double-side polishing apparatus according to the present invention.

FIG. 2 is a side sectional view of the embodiment of FIG. 1;

FIG. 3 is a plan view and a cross-sectional view showing the entire carrier and carrier holder of the embodiment of FIG. 1;

FIG. 4 is a cross-sectional view illustrating a main part of a linking means according to the present invention.

FIG. 5 is a plan view and a sectional view showing another embodiment of the connecting means according to the present invention.

FIGS. 6A and 6B are a plan view and a side view illustrating an embodiment of the correcting means according to the present invention.

FIGS. 7A and 7B are a plan view and a side view illustrating a correction means of the background art.

FIG. 8 is a cross-sectional view illustrating a conventional technique.

FIG. 9 is a plan view illustrating the arrangement of carriers according to the related art.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Wafer 12 Carrier 12a Through-hole 12b Hole 14 Upper surface plate 14a Polishing surface 14b Hole for supplying abrasive 15 Communication hole 16 Lower surface plate 16a Polishing surface 20 Carrier turning mechanism 22 Carrier holder 23 Pin 24 Crank member 24a Holder side shaft 24b Base-side shaft 28 Timing chain 30 Base 32 Motor 40 Upper platen elevating device 65 Carrier elevating device 66 Upper platen correcting means 67 Correcting member 68 Lower platen correcting means 69 Rotating arm

Claims (5)

[Claims] 1. A carrier in which a thin plate is provided with a through hole, and a plate-like work disposed in the through hole of the carrier is sandwiched from above and below and is moved relatively to the work to polish the work. An upper surface plate and a lower surface plate, and the carrier is made to make a circular motion that does not rotate in a plane parallel to the surface of the carrier, and the work held between the upper surface plate and the lower surface plate in the through hole. A carrier swivel mechanism for swiveling the upper surface plate, an elevating device for moving the upper surface plate up and down so as to move the upper surface plate toward and away from the carrier, and an elevating device so as to move the carrier toward and away from the lower surface plate A carrier elevating device, which is provided so as to be able to advance and retreat between the upper surface plate and the carrier,
Correction means for correcting the polished surface of the upper stool, provided between the lower stool and the carrier so as to be able to advance and retreat,
A double-side polishing apparatus, comprising: a correction unit configured to correct a polishing surface of the lower platen. 2. The double-side polishing apparatus according to claim 1, wherein said correcting means is an injection nozzle which jets a brush and / or a pressure fluid and blows the same onto the polishing surface. 3. The double-side polishing apparatus according to claim 1, wherein the upper surface plate and the lower surface plate are driven to rotate around an axis parallel to a direction perpendicular to the surface of the carrier. 4. The carrier swiveling mechanism comprises: a carrier holder for holding the carrier; a holder-side shaft having an axis parallel to a direction perpendicular to a surface of the carrier and being axially mounted on the carrier holder; And a base-side shaft which is parallel to the holder-side shaft and is attached to the base at a predetermined distance from the base-side shaft, and the holder-side shaft is turned around the base-side shaft. 4. A crank member for rotating the carrier holder in a circular motion without rotating with respect to the base, and a driving device for rotating the crank member about a shaft on the base side. Double-side polishing machine. 5. The apparatus according to claim 1, wherein a plurality of the crank members are provided, and the shafts on the base side are connected to each other by a synchronization means such as a timing chain so that the plurality of crank members make a circular motion in synchronization. The double-side polishing apparatus according to claim 4.