JPH11104942A - Method of and device for polishing work edge - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a polishing means of rough polishing and finish polishing a work edge unwastefully and efficiently. SOLUTION: A polishing drum 2 having a first work surface 5 for rough polishing with fixed grains carried thereon and a second work surface 6 for finish polishing consisting of a polishing pad to both sides of axial direction is used. After pressing and rough polishing the outer periphery edge of a work 1 held on work holding means 3a, 3b to the first work surface 5 of the polishing drum 2, a finish polishing is carried out while pressing to the second work surface 6.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for polishing a chamfered edge portion of an outer periphery of a substantially disk-shaped work such as a semiconductor wafer or a magnetic disk substrate. is there.

[0002]

2. Description of the Related Art For example, an outer peripheral edge portion of a semiconductor wafer, a magnetic disk substrate or the like is generally chamfered, and various polishing apparatuses have been proposed for polishing the chamfered edge portion. For example, Japanese Patent Application Laid-Open No. 1-7
Japanese Patent Application Laid-Open No. 1656 discloses a method in which a polishing pad is attached to an outer peripheral surface of a polishing drum, and an outer peripheral edge of a wafer is pressed against the polishing pad to perform polishing while supplying an abrasive containing free abrasive grains. Japanese Unexamined Patent Publication No. Hei 7-171749 discloses a technique in which a polishing tape carrying fixed abrasive grains is wound around a rotating drum, and the outer peripheral edge of a wafer is pressed against the polishing tape to perform polishing.

[0003] However, there is a difference in polishing time and polishing accuracy between the case of using a polishing pad and the case of using a polishing tape. For example, when a polishing pad is used, the polishing time is slightly slow but the surface accuracy is low. When the polishing tape is used, the polishing time is short but the surface accuracy is low. Therefore, conventionally, in order to enhance the productivity, the above-mentioned Japanese Patent Application Laid-Open No.
In many cases, the edge is roughly polished with a polishing tape using a device as disclosed in Japanese Patent Application Laid-Open No. 9-209, and then finish polishing is performed using a polishing pad.

However, such a conventional method is
There is a great deal of waste because two different types of polishing equipment have to be used. For example, a large space is required for installing two types of polishing apparatuses, a work positioning mechanism, a transport mechanism, and the like are provided in each polishing apparatus. Another point is that another transport mechanism for transferring the work between them is required.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to make it possible to perform rough polishing and finish polishing of a work edge efficiently by a common polishing means without waste.

[0006]

In order to solve the above-mentioned problems, the present invention uses a polishing drum having a first work surface for rough polishing and a second work surface for finish polishing on both axial sides. The method is characterized in that the outer peripheral edge of the work held by the work holding means is pressed against the first work surface of the polishing drum for rough polishing, and then pressed against the second work surface for finish polishing.

According to the present invention, the rough polishing and the finish polishing, which conventionally had to be performed by using two types of polishing apparatuses of different types, can be easily and simply performed by using one polishing apparatus. The polishing can be performed efficiently, and the use of a common polishing apparatus can reduce waste in equipment and space.

According to a specific mode of the present invention, the first working surface is formed by a member carrying fixed abrasive grains such as a polishing tape or a grindstone, and the second working surface is formed by a polishing pad. ing.

In the present invention, it is preferable that the polishing drum is disposed vertically so that the first work surface is located below and the second work surface is located above, so that the first work surface is provided during the rough polishing. Since the abrasive grains separated from the surface do not adhere to the second work surface, the peeled abrasive particles do not adversely affect the subsequent finish polishing by the second work surface, and the polishing accuracy can be improved. it can.

According to another specific embodiment of the present invention,
Two work holding means are provided on both sides of the polishing drum, and a reversing means for reversing the work is provided. The first work holding means operates the front side edge of the work on the first side of the polishing drum. The second work holding means is configured to press and grind against the surface by pressing the back side edge of the work against the work surface on the second side of the polishing drum.

In the present invention, two polishing drums may be provided, and the workpiece may be pressed against these two polishing drums at the same time to perform polishing at two points.

[0012]

1 and 2 show a first embodiment of a polishing apparatus according to the present invention. The polishing apparatus includes a cylindrical polishing drum 2 for polishing an outer peripheral edge of a work 1, and first and second two polishing machines for holding the work 1 and pressing the work 1 against a work surface on the outer periphery of the polishing drum 2. Work holding means 3a, 3b and reversing means 4 for reversing the work 1 are provided.

The polishing drum 2 has a first work surface 5 for rough polishing and a second work surface 6 for finish polishing on both sides in the axial direction. (2) Mounted on a substrate 7 with the working surface 6 facing upward so as to be rotatable with the axis line directed vertically, and connected to a motor 8. The motor 8 can freely control the rotating direction and the rotating speed.

The first work surface 5 is constituted by wrapping a polishing tape 5a carrying fixed abrasive grains around the outer surface of the drum, and the second work surface 6 is constituted by a polishing pad adhered to the outer surface of the drum. Have been.

The polishing tape 5a is wound around the polishing drum 2 and a small-diameter tension roller 9 rotatably mounted on a substrate 7, as can be seen from FIG.
In a state where the necessary tension is applied by the tension roller 9, the polishing roller 2 is driven by rotation of the polishing drum 2 to orbit around the polishing drum 2 and the tension roller 9.

An elevating shaft 10 is mounted on the lower surface of the substrate 7, and the elevating shaft 10 is provided with a moving mechanism 11 and a swing mechanism 12
And are linked to The moving mechanism 11 selectively moves the workpiece 1 to the first work surface 5 or the second work surface 6 of the polishing drum 2 by moving the substrate 7 (therefore, the polishing drum 2) up and down. , A ball screw and a nut member screwed thereto. On the other hand, the swing mechanism 12 swings the substrate 7 (therefore, the polishing drum 2) up and down to change the contact position of the work 1 with the work surfaces 5 and 6 during edge polishing. It can be configured by a combination.

The work holding means 3a and 3b hold the disc-shaped work 1 having the chamfered outer edges 1a and 1b on the front and back surfaces as shown in FIG. The outer peripheral edges 1a and 1b are
The work surfaces 5 and 6 are arranged at positions facing each other with the polishing drum 2 interposed therebetween. The first work holding means 3a provided on the first side of the polishing drum 2 includes:
The edge 1a on the front side of the work 1 is pressed against each of the work surfaces 5 and 6 for polishing. The second work holding means 3b disposed on the second side of the polishing drum 2 is provided on the back side of the work 1. Is polished by pressing the edge 1b of each of the working surfaces 5 and 6 against the working surfaces 5 and 6 described above.

The two work holding means 3a and 3b have the same configuration and are configured as follows. That is, the work holding means 3a and 3b include a chuck head 15 for vacuum chucking the work 1 and a first body 16 for rotatably holding the chuck head 15.
And a second body 17 that supports the first body 16 so as to be tiltable about a support shaft 18. The second
The body 17 is mounted on a slide member 19 by a leg 17a, and the slide member 19 is linearly movable on a rail 21 installed on a plate 20a integral with the body 20 in a direction of coming into contact with and separating from the polishing drum 2. It is placed so that it becomes.

A pulley 24 is attached to the plate 20a, and a wire 25 is wound around the pulley 24. One end of the wire 25 is fixed to an arm 19a extending downward from the slide member 19, and the wire 25 A weight 26 is hung from the tip of. An air cylinder 27 is attached to the plate 20a, and a tip of a rod 27a of the air cylinder 27 is in contact with the arm 17a.

Therefore, the rod 2 of the air cylinder 27
When the work holding means 3a, 3b is extended, the work holding means 3a, 3b retreats on the rail 21 to a non-polishing position separated from the polishing drum 2 while lifting the weight 26, as shown in the right half of FIG. When shortened, as shown in the left half of FIG. 1, the work 1 advances to the polishing position where the work 1 contacts the polishing drum 2 by the gravity of the weight 26. When the work 1 comes into contact with the polishing drum 2, the work holding means 3
a and 3b stop at that position, but after that the rod 2
7a is slightly shortened and separated from the arm 19a, so that the work 1 is pressed against the polishing drum 2 by the gravity of the weight 26. Therefore, the weight 26 is
This constitutes an urging means for pressing the work 1 against the polishing drum 2 at a constant pressure during polishing. 28 in the figure
Is a stopper for defining the retreat position of the work holding means 3a, 3b.

The chuck head 15 has a plurality of suction holes on its surface, and these suction holes are evacuated through ports, piping tubes, and the like provided in the first body 16 and the second body 17. Sources, but their illustration is omitted.

As shown in the right half of FIG. 2, the first body 16 has a non-inclination position where the chuck head 15 is oriented horizontally to separate the work 1 from the polishing drum 2 and a left side in FIG. As shown in the half section, the chuck head 15 is shifted between the inclined position where the chuck head 15 is inclined forward to contact the work edge with the polishing drum 2. In the figure, reference numeral 29 denotes a nozzle for supplying a polishing liquid such as water or an abrasive to the polishing portion.

The reversing means 4 has a reversible chuck head 35 for vacuum chucking the work 1 at the tip of a multi-joint arm 34 which can flex and extend.
It is arranged so as to be movable between the two work holding means 3a and 3b.

In the polishing apparatus having the above-described structure, the unprocessed work is moved by the loading means (not shown) to the chuck head 1 of the first work holding means 3a at the non-polishing position.
5, the first body 16 tilts forward to the tilt position. Then, the rod 27a of the air cylinder 27 is shortened, and the first work holding means 3a advances on the rail 21 in the direction of the polishing drum 2, and the front edge of the work 1 which is held and rotated by the chuck head 15 is rotated. 1a is pressed against the first work surface 5 below the rotating polishing drum 2 to be roughly polished. The contact pressure of the work 1 on the work surface 5 at this time is obtained by the gravity of the weight 26. During the polishing, a polishing liquid is supplied from the nozzle 29. Further, by swinging the substrate 7 in the axial direction of the polishing drum 2 by the swing mechanism 12, the work 1
Is changed, and uneven wear of the first work surface 5 is prevented.

When the rough polishing by the first work surface 5 is completed, the substrate 7 is lowered by the moving mechanism 11 to change the work surface, and the finish polishing by the second work surface 6 is performed. At this time, the work surface is changed by retreating the first work holding means 3a by the air cylinder 27 to move the work 1 to the first work surface 5a.
After the polishing drum 2 is lowered by the moving mechanism 11 in this state, the first work holding means 3a is advanced again to bring the work 1 into contact with the second work surface 6. desirable. In addition, it is desirable to change the rotation speed of the polishing drum 2 between the time of rough polishing on the first work surface 5 and the time of finish polishing on the second work surface 6.

When the finish polishing by the second work surface 6 is completed, the polishing of the edge 1a on the front side of the work 1 is completed, and the first work holding means 3a is retracted by the air cylinder 27 to the non-polishing position. The first body 16 returns to the non-inclination position and turns the work 1 horizontally.

Next, the reversing means 4 receives the work 1 from the first work holding means 3a, turns it over and supplies it to the second work holding means 3b. At the same time the first
The next unprocessed work is supplied to the work holding means 3a by the loading means. Then, as in the case of the above-described polishing of the front-side edge 1a, on the second side of the polishing drum 2, the second work holding means 3b causes the back-side edge 1b of the work 1 to move to the first and second work surfaces 5,5. 6, and on the first side of the polishing drum 2, the first work holding means 3 a is used to polish a new edge 1 a on the front side of the work 1.
Is polished by both working surfaces 5, 6.

When the above polishing is completed, the work 1 held by the second work holding means 3b and having finished polishing the back side edge 1b is taken out by an unloading means (not shown) and sent to the next step to hold the first work. The work 1 whose front edge 1a has been polished by the means 3a is
Is supplied to the second work holding means 3b. By repeating the above steps, the outer peripheral edges 1a and 1b of the front and back surfaces of the work 1 are efficiently polished by the continuous steps.

A first work surface 5 for rough polishing and a second work surface 6 for finish polishing are formed on one polishing drum 2.
By selectively using the work surfaces 5 and 6 to perform both rough polishing and finish polishing, the work edge can be efficiently polished without waste using one polishing apparatus. Since it is not necessary to use two different types of polishing apparatuses as in the related art, there is no waste in equipment and space. In addition, since the first work surface 5 carrying the fixed abrasive grains is positioned below the second work surface 6, the abrasive grains separated from the first work surface 5 during polishing are transferred to the second work surface 6. There is no adhesion, and the peeled abrasive grains do not adversely affect the subsequent finish polishing by the second work surface 6.

FIG. 4 shows a second embodiment of the present invention.
The polishing apparatus of the second embodiment has two polishing drums 2 and 2
So that the outer peripheral edges 1a and 1b of the work 1 are simultaneously brought into contact with the working surfaces 5, 5 or 6 and 6 of these two polishing drums 2 and are polished at two points. . That is, two polishing drums 2, 2 are juxtaposed on the substrate 7 with an interval smaller than the diameter of the work 1, and two work holding means 3a, 3b are provided just in the middle of the two polishing drums 2, 2. It is arranged to be located.

Since the construction and operation other than those described above are substantially the same as those of the first embodiment, the same components as those of the first embodiment will be described.
The same reference numerals as in the embodiment are used and the description is omitted. As in the second embodiment, by providing a plurality of polishing drums 2 and simultaneously polishing the work edge at a plurality of points, the polishing efficiency can be increased and the polishing time can be greatly reduced.

In the second embodiment, in order to prevent the work 1 from hitting one of the polishing drums 2, the work holding means 3 a, 3 b is provided with two polishing drums 2, 2. It is desirable to have a degree of freedom in the direction parallel to the line connecting the centers. As means for providing this degree of freedom, for example, as shown in FIG. 5, the second rail 3 in the direction orthogonal to the rail 21 is provided on the upper surface of the slide member 19.
1 and a second slide member 3 on the second rail 31.
2 may be slidably mounted, and the second body 17 of the work holding means 3a, 3b may be attached to the second slide member 32.

It is desirable that the working surfaces 5, 6 of the polishing drum 2 have such a flexibility that the work 1 can bite slightly, whereby the edges 1a, 1b on the front and back surfaces are formed.
And the outer peripheral surface 1c can be polished at the same time.

In the above embodiment, the urging means for setting the contact pressure of the work 1 during the polishing is constituted by the weight 26. Instead of the weight 26, an air cylinder having a pressure adjusting means is used. You may comprise. Also, the first
The work surface 5 is formed by the polishing tape 5a, but may be formed by a grindstone.

[0035]

As described above, according to the present invention, the first work surface for rough polishing and the second work surface for finish polishing are formed on one polishing drum, and these work surfaces are selectively used selectively. Since the work edge is polished by using a single polishing apparatus, the rough polishing and the finish polishing, which conventionally had to be performed by using two different types of polishing apparatuses individually, are wastefully performed by using one polishing apparatus. It is possible to perform the polishing efficiently without using the same polishing apparatus, and it is possible to reduce waste in equipment and space.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a first embodiment of a polishing apparatus according to the present invention.

FIG. 2 is a plan view of FIG.

FIG. 3 is a side view of a main part of the first embodiment.

FIG. 4 is a sectional view showing a second embodiment of the polishing apparatus according to the present invention.

FIG. 5 is a sectional view of a main part of a second embodiment.

FIG. 6 is a partial side view of a work.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Work 1a, 1b Edge 2 Polishing drum 3a, 3b Work holding means 4 Reversing means 5 First working surface 6 Second working surface 5a Polishing tape 8 Motor (driving means) 11 Moving mechanism 26 Weight (biasing means)

Claims (10)

[Claims] 1. A rotating work piece using a polishing drum having a first work surface for rough polishing and a second work surface for finish polishing on both sides in the axial direction, and rotating the polishing drum around the axis. A method of polishing a work edge, comprising: contacting the outer peripheral edge of the first work surface with the first work surface for rough polishing, and then contacting the second work surface for finish polishing. 2. The polishing method according to claim 1, wherein the polishing drum is vertically arranged such that the first working surface is located at a lower position and the second working surface is located at an upper position, thereby finishing the rough polishing. The polishing is performed at a position lower than the polishing. 3. The polishing method according to claim 1, wherein the polishing drum or the workpiece is relatively moved in an axial direction of the polishing drum to change a contact position on a work surface. thing. 4. At least one polishing drum having a first working surface for rough polishing and a second working surface for finish polishing on both sides in the axial direction; driving means for rotating the polishing drum around the axis; At least one work holding means for holding and rotating a disk-shaped work having an outer peripheral edge formed thereon and bringing the outer peripheral edge of the work into contact with each work surface of the polishing drum; To selectively contact the work surface and the second work surface,
Moving means for relatively moving the polishing drum or the work holding means in the axial direction of the polishing drum; and a polishing apparatus for a work edge. 5. The polishing apparatus according to claim 4, wherein the first working surface is formed by a member carrying fixed abrasive grains,
The second working surface is formed by a polishing pad. 6. The polishing apparatus according to claim 5, wherein the polishing drum is vertically arranged such that the first work surface is located below and the second work surface is located above. What to do. 7. A polishing apparatus according to claim 4, wherein said polishing drum and said work holding means are relatively positioned in the axial direction of said polishing drum in order to change a contact position of said work with respect to a work surface. It is characterized by being movable. 8. A polishing apparatus according to claim 4, wherein said work holding means has a biasing means for bringing a work into contact with a work surface with a constant force during processing. What to do. 9. The polishing apparatus according to claim 4, wherein said polishing drum is interposed between said first and second polishing machines.
Two work holding means are provided, and a reversing means for turning the work upside down is provided.
The second work holding means presses and grinds the back surface side edge of the work against the work surface on the second side of the polishing drum. 10. The polishing apparatus according to claim 9, wherein 2
One polishing drum is provided at an interval smaller than the diameter of the work, and the work is pressed against these two polishing drums at the same time to be polished at two points.