JPH1190802A - Method and device for polishing chamfered face of wafer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method capable of satisfactorily polishing the whole inner peripheries of the notched sections of a wafer and a device thereof of simple structure and a low cost. SOLUTION: This polishing device is equipped with wafer retaining structure 5 to retain a wafer W chamfered at its outer circumference and notched sections, in a given position, a notched section polishing wheel 24 installed as to intersect the wafer W and rotated on an axis, energizing mechanism 28 to energize and press the notched section polishing wheel 24 against the notched sections of the wafer W with an almost constant pressure, and reciprocating mechanism to move the notched section polishing wheel 24 and the energizing mechanism 28 back and forth in the direction as to intersect the face of the wafer W at right angles. By reciprocating the notched section polishing wheel 24 across the wafer face at right angles while pressing the wheel 24 against the inner face of the notched sections with a constant pressure, the notched section polishing wheel 24 advances or retreats in the diametral direction of the wafer W following the contour of the inner face of the notched section.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for polishing a chamfered surface for mirror-finishing an inner surface of a notch formed on an outer peripheral portion of a wafer such as a semiconductor wafer and a polishing apparatus therefor.

[0002]

2. Description of the Related Art A substantially V-shaped or substantially arc-shaped notch is formed on an outer peripheral portion of a semiconductor wafer (hereinafter, referred to as a wafer). It has been widely adopted for the purpose of improving the yield. As shown in FIG. 8A, the wafer W having the V-shaped notch 1a is provided with an outer chamfered surface 2e at the upper and lower corners of the edge in order to prevent chipping of the edge and crown during epitaxy growth. , 2d are formed. In order to remove the remaining of the processing distortion layer at the edge portion at the time of chamfering, there has been proposed a mirror finishing apparatus for performing mirror finishing by bringing a drum-shaped mirror finishing means into contact with the outer peripheral chamfered surfaces 2e and 2d. (See, for example,
274958, etc.).

Since the size of the notch 1a is extremely small compared to the outer peripheral length of the wafer W, the notch 1a is formed on the wafer W using the drum-shaped mirror processing means. It was difficult to perform mirror finishing. Therefore, as shown in FIGS. 8B and 8C, the notch portion 1a of the wafer W arranged in a horizontal state.
Generally, the non-chamfered surface (outer surface) c of the notch portion 1a is efficiently polished by pressing the rotating polishing wheel 100, which is arranged orthogonally to the wafer W and rotates, horizontally. With this technology,
There is a problem that the chamfered surfaces 2a and 2b of the notch portion 1a cannot be efficiently polished.

In order to solve this problem, a polishing apparatus capable of polishing both the chamfered surface and the non-chamfered surface of the notch has been proposed. Hereinafter, this polishing apparatus will be described with reference to two typical examples. I do.

(1) First, as shown in FIG. 9, this polishing apparatus comprises a table 101 capable of holding a wafer W having a notch (not shown) formed in a part of the outer periphery, and a wafer W
A rotatable buff 102 rotatable about an axis parallel to the wafer surface and having an outer peripheral shape substantially similar to a notch portion, and a first motor (not shown) for rotating the rotatable buff 102 around its axis. ), A cylinder device 104 for bringing the rotating buff 102 into and out of contact with the wafer W held on the table 101 via the holding link 103, and the table 101 with the inner surface of the notch (not shown) of the wafer W. A second motor (not shown) for swinging the rotary buff 102 so as to come into contact with the entire region (see Japanese Patent Application Laid-Open No. 7-24714). In this polishing apparatus, by rotating the table 101 holding the wafer W, the rotating rotary buff 102 follows the inner surface of the notch, and the inner surface of the notch is polished. A polishing apparatus that performs the same operation as this polishing apparatus is also disclosed in Japanese Patent Laid-Open No. 8-168947.

(2) As shown in FIG. 10, this polishing apparatus arranges a rotating disc-shaped grindstone 105 and a wafer W such that the surface thereof intersects the disc-shaped grindstone 105, and the wafer W Holding mechanism rotatably around a central axis perpendicular to the surface thereof (see arrow θ) within a predetermined angle range, and the wafer holding mechanism 106 with a disc-shaped grindstone 105 and a wafer W A first drive mechanism 107 for moving in the radial direction (see the arrow X direction) so as to approach or separate from the other, and a second drive mechanism for moving the disc-shaped grindstone 105 in the thickness direction of the wafer W (see the arrow Z direction). (See Japanese Patent Publication No. 2613504). In this polishing apparatus, the wafer W is rotated around its central axis (arrow θ
By moving the wafer W in the direction of the arrow X and moving the rotating disk-shaped grindstone 105 in the direction of the arrow Z, the chamfered surfaces 2a and 2b and the non-chamfered surface 2c of the notch 1a can be polished. it can.

[0007]

However, in the case of the above (1), as shown in FIG. 9, by rotating the wafer W between a horizontal state and a vertically inclined state, the rotating hub 102 is rotated. Is pressed against a notch portion at a fixed position and is polished, so that there is a problem that it is not possible to satisfactorily polish the vicinity of the chamfered surface in particular on the wafer surface side. By tilting the wafer W greatly, the vicinity of the chamfer surface on the wafer surface side can be polished to some extent satisfactorily, but the mechanism for tilting the wafer W becomes complicated and the wafer W is shaken. The wafer W may be deformed by the inertial force acting on the wafer W when moving.

On the other hand, the method (2) moves both the wafer and the disk-shaped grindstone, so that the mechanism for the movement is complicated and the timing of movement of the wafer and the disk-shaped grindstone is slightly shifted. In this case, there is a problem that the chamfered surface of the notch cannot be polished well. That is, in the case of (2), a good polished surface of the chamfered portion can be achieved by the wafer and the disk-shaped grindstone moving at the correct timing in synchronization with each other, and for this purpose, A highly accurate and expensive control system is required as a control system for controlling the timing of the movement of the disc-shaped grindstone.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems of the prior art, and a method for polishing a chamfered surface of a wafer, which can easily and satisfactorily mirror-polish the entire inner peripheral surface of a notch, and this polishing method. It is an object of the present invention to provide a wafer chamfering surface polishing apparatus having a simple structure and a low apparatus cost for carrying out the method.

[0010]

According to the present invention, there is provided a method for polishing a chamfered surface of a wafer, comprising: holding a wafer having a chamfered outer peripheral edge and a notch at a fixed position; To the notch portion of the wafer, the outer peripheral portion of the notch portion polishing wheel, which intersects with the wafer, is urged to press with a predetermined pressure,
The method is characterized in that the notch portion polishing wheel is reciprocated in a direction substantially orthogonal to the wafer surface of the wafer while being rotated about its axis.

According to the operation of the present invention, a notch polishing wheel having an outer peripheral shape substantially matching the notch shape is pressed against a notch portion of a wafer at a predetermined position so as to press the wheel at a predetermined pressure, In this state, the notch polishing wheel is rotated about its axis and reciprocated in a direction substantially orthogonal to the wafer surface of the wafer. This allows
The notch portion polishing wheel, by the reaction of the polishing pressure received from the notch portion, advances and retreats in the radial direction of the wafer along the inner surface shape of the notch portion, and can satisfactorily polish the inner surface of the notch portion at a constant polishing pressure, A mirror surface can be satisfactorily processed even in the vicinity of the wafer surface at the notch.

As a polishing apparatus for carrying out this method, a wafer holding mechanism for holding a wafer having a chamfered outer peripheral edge portion and a notch portion at a fixed position, and a wafer holding mechanism arranged so as to intersect with the wafer, A notch polishing wheel that rotates around an axis, and the notch polishing wheel is held, and the notch polishing wheel is urged so that an outer peripheral portion thereof presses the notch of the wafer with a predetermined pressure. A biasing mechanism; and a reciprocating mechanism that drives the biasing mechanism such that the notch polishing wheel reciprocates in a direction substantially orthogonal to the wafer surface of the wafer. It is.

The urging mechanism includes a polishing pressure applying cylinder driven by the reciprocating mechanism and the notch polishing wheel at one end, and the other end is attached to a rod of the polishing pressure applying cylinder. A polishing arm that is rotatably connected and that is rotatably supported at an intermediate portion as a fulcrum. In this way, the notch polishing wheel is urged against the notch of the wafer by the power of the polishing pressure applying cylinder, which is easy to maintain and inexpensive.

A rotating mechanism for rotating the wafer holding mechanism around the axis of the wafer; an outer peripheral chamfered polishing member and an outer peripheral non-chamfered member for polishing an outer chamfered surface and an outer non-chamfered surface of the wafer, respectively; And a chamfered polishing member. Thus, before or after the polishing of the notch portion, the wafer is rotated around its central axis by the wafer holding means, and the rotating outer chamfered polishing member and the outer non-chamfered polishing member are moved to the outer chamfered surface and the outer periphery of the wafer. Mirror polishing can be performed by pressing each of the non-chamfered surfaces.

[0015]

Next, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is an embodiment of a wafer chamfering surface polishing apparatus according to the present invention, in which a cross section of an apparatus main body and an apparatus exterior is shown, FIG. 2 is a left side view of FIG. 1, and FIG. FIG. 2 is a schematic view when viewed from the right.

The chamfered-surface polishing apparatus according to the present embodiment uses the notch 1a of the wafer W held by the wafer suction disk 3.
4 and 5 are mirror-polished by a notch polishing wheel 24, and an outer peripheral chamfered surface 2d (see FIG. 6) of the wafer W and an outer peripheral polishing drum 30 and an outer peripheral polishing disk 31 (see FIG. 3). The outer peripheral non-chamfered surface 2f (see FIG. 7) can be mirror-polished, and will be described in detail below.

First, as shown in FIGS. 1 and 2, an apparatus base 1 is provided with an apparatus exterior 2 for forming a polishing work space inside. A support rod 4 is provided on one side (right side in FIG. 1) inside the device exterior 2 so as to be able to move up and down so as to penetrate the device exterior 2 and to be rotatable about an axis (see arrow C). At the lower end of the support rod 4, a wafer suction disk 3 for holding a wafer W as an object to be polished in a horizontal state is provided. The wafer suction mechanism 3 and the support rod 4 constitute a wafer holding mechanism 5. As shown in FIG. 3, the rotation mechanism 39 for rotating the support rod 4 includes a rotation motor (not shown) to which a speed reducer is connected and a rotation angle detection for detecting the rotation angle of the wafer suction plate 3. And a sensor (not shown).

On the side of the apparatus base 1, a cylinder 6 for moving the polishing unit forward and backward is fixed with its rod 6a directed horizontally (leftward in FIG. 1). A polishing unit support bracket 8 for supporting a notch portion polishing unit 7 described below is fixed to the side of the apparatus base 1. A box-shaped polishing unit main body 11 is supported by the polishing unit supporting bracket 8 via a slide mechanism 9 so as to be movable in a horizontal direction (left and right directions in FIG. 1). Is connected to the rod 6a of the cylinder 6 for moving the polishing unit forward and backward. When polishing is performed based on such a configuration, the rod 6a of the polishing unit advance / retreat cylinder 6 is retracted,
The notch polishing unit 7 is moved to the wafer W side (rightward in FIG. 1), and when polishing is completed, the rod 6a of the polishing unit advance / retreat cylinder 6 is protruded to move the notch polishing unit 7 to the wafer W side. It can be evacuated in the opposite direction. The state shown in FIG. 1 shows a state during polishing.

With respect to the detailed structure of the polishing unit 7, an elevating motor 12 is fixed to the polishing unit main body 11 with its rotating shaft (output shaft) 12a facing upward. A ball screw shaft 14 is coaxially connected to a rotary shaft 12 a of the elevating motor 12 via a coupling 13, and an elevating member 15 is screwed to the ball screw shaft 14. The elevating member 15 is supported by a vertically extending guide shaft 16 fixed to the polishing unit main body 11 so as to be vertically movable.
5, a cylinder bracket 17 described later is fixed. By rotating the rotating shaft 12a of the lifting motor 12 in one direction based on such a configuration, the lifting member 15 screwed to the rotating ball screw shaft 14 rises, while the lifting motor 12 is turned upside down. When rotated, the elevating member 15
Descends. The lifting motor 12 and the ball screw shaft 1
The reciprocating mechanism 29 is constituted by the lifting member 4 and the lifting member 15.

A polishing pressure applying cylinder 18 is fixed to the cylinder bracket 17 with its rod 18a facing almost directly above.
One end of a polishing arm 19 that bends in a "<" shape is rotatably connected to the tip of the rod 18a via a pin member 20 or the like. On the other hand, an intermediate portion 19a of the polishing arm 19 is rotatably supported by a fixed bracket 21 extending laterally from the elevating member 15. One end of a substantially oval-shaped polishing wheel support member 22 is integrally fixed to the other end of the polishing arm 19.

A polishing motor 23 is fixed to one end of the polishing wheel support member 22, and the polishing wheel support member 2
A notch polishing wheel 24 is rotatably supported on the other end of the second member 2 around its axis (in its circumferential direction). The rotation of the polishing motor 23 is transmitted to the notch polishing wheel 24 via a transmission mechanism (not shown) such as a pulley or a belt, whereby the notch polishing wheel 24 is moved in one direction. (See arrow A in FIG. 1). Notch polishing wheel 2
The shape of the outer peripheral portion of the wafer 4 is such that it matches the shape of the notch portion 1a of the wafer W.

When the notch portion 1a is polished, the rod 18a of the polishing pressure applying cylinder 18 is retracted, whereby the polishing arm 19 is rotated counterclockwise in FIG. Part grinding wheel 24
Is moved to the wafer W side (see arrow B in FIG. 4), whereby the outer peripheral portion of the notch portion polishing wheel 24 is moved to the notch portion 1 of the wafer W.
It can be urged to press a at a predetermined polishing pressure (1.5 to 3.5 kg / mm ² ). On the other hand, at the time of non-polishing, the rod 18a of the polishing pressure applying cylinder 18 is projected so that the polishing arm 19 is rotated clockwise in FIG. The wheel support member 22 is retracted in a direction away from the wafer W.

As is clear from the above description, the urging mechanism 2 is constituted by the polishing pressure applying cylinder 18 and the polishing arm 19 and the like.
8 are configured. A polishing liquid supply means (not shown) for supplying the polishing liquid to the notch portion 1a of the wafer W at the time of polishing is provided.
It is discharged from the device exterior 2 and collected.

The polishing arm 19, the polishing wheel support member 22, the polishing motor 23, and the like are connected to the polishing unit main body 1.
1 is accommodated in a cover member 25 fixed to the cover 1, and the cover member 25 is supported by a bellows 26 movably in a horizontal direction with respect to the apparatus exterior 2. The cover member 25 has an opening through which the notch polishing wheel 24 can pass.

The polishing apparatus of this embodiment can polish the outer peripheral chamfered surface 2d and the outer peripheral non-chamfered surface (outer end surface) 2f in addition to the notch portion 1a of the wafer W.
That is, as shown in FIG. 3, the outer peripheral chamfered surface 2d of the wafer W is provided on both sides of the notch portion polishing wheel 24.
And an outer peripheral polishing disk 31 (outer peripheral non-chamfered polishing member) for polishing the outer non-chamfered surface 2f of the wafer W are arranged. ing.

More specifically, the outer peripheral polishing drum 30 is rotatably supported with its outer peripheral surface covered with a chamfering polishing cloth 34 and having an axis perpendicular to the axis of the wafer W. Drum drive means 36 for rotating is provided. The outer peripheral polishing drum 30 includes a drum driving unit 36.
And a rotatable drum rotating shaft member 32 connected to a motor (not shown), and a drum main body 33 made of an aluminum alloy or the like and provided at the tip end of the drum rotating shaft member 32 with the same axis. The polishing cloth for chamfered surface 34 is fixed to the outer peripheral surface of the drum main body 33 in a wound state.

The drum driving means 36 includes a drum linear motion unit (not shown) having a ball screw for moving the outer peripheral polishing drum 30 forward and backward in the axial direction, a motor for rotating the ball screw, and the like; A pressing cylinder (not shown) for bringing the 30 into contact with the chamfered surface of the wafer W in a pressed state is provided.

The outer peripheral polishing disk 31 is formed by covering the surface of a disk main body 35 with an outer surface polishing cloth 37, and is rotatably supported with an axis perpendicular to the axis of the wafer W. A disk driving means 38 for rotating the outer peripheral polishing disk 31 is provided. The disk driving means 38 includes a disk moving mechanism for moving the outer peripheral polishing disk 31 in the axial direction of the wafer W (vertical direction) during polishing.

In the vicinity of the outer peripheral polishing drum 30 and the outer peripheral polishing disk 31, a polishing liquid is applied during polishing to the outer peripheral polishing drum 3.
A polishing liquid supply means (not shown) for supplying the polishing liquid to the chamfered surface and the outer surface of the wafer W while supplying the polishing liquid to the 0 and outer peripheral polishing disks 31 is provided.

Next, an example of a method for polishing a chamfered surface of a wafer in an embodiment of the apparatus for polishing a chamfered surface of a wafer according to the present invention will be described. Note that the polishing method of the present example described below first polishes the notch portion 1a of the wafer W, and then polishes the outer chamfered surface 2b and the outer non-chamfered surface 2c of the wafer W. May be reversed.

First, as shown in FIG. 1, the wafer W is lowered by the wafer suction plate 3, and the wafer W is arranged at a predetermined height. The notch 1a of the wafer W (FIG. 4)
) Is opposed to the notch grinding wheel 24,
The wafer suction plate 3 is rotated to position the wafer W in the circumferential direction.

Next, the reciprocating cylinder 6 for the polishing unit is operated to move the notch polishing unit 7 at the retracted position (two-dot chain line) toward the wafer W (to the right in FIG. 1). To hold. Thereafter, the polishing arm 19 is rotated clockwise around the fulcrum 19a by a predetermined angle by the polishing pressure applying cylinder 18, so that the notch portion polishing wheel 24 has a wafer W side as shown in FIGS. (See arrow B in FIG. 4), and the outer peripheral portion of the notch portion polishing wheel 24 is moved to the notch portion 1 of the wafer W.
a with a predetermined pressing force (1.5 to 3.5 kg / mm ² ) substantially perpendicularly to the chamfered surface 2 a below the lower surface a. That is, the notch polishing wheel 24 is urged to press the notch 1 a of the wafer W by the pressure of the polishing pressure applying cylinder 18.

In this state, the polishing motor 23 is operated to rotate the notch polishing wheel 24, and the reciprocating rotation of the elevating motor 18 is repeated, whereby the entire polishing arm 19 is reciprocated vertically. By
The rotating notch polishing hole 24 also reciprocates vertically. At this time, as shown in FIG. 5, the notch portion grinding wheel 24 constantly presses the inner peripheral surface of the notch portion 1a in a substantially vertical direction with a constant pressure, and this reaction is combined with the cushioning effect of the polishing pressure applying cylinder 18. Reciprocating between the solid line position 24 and the alternate long and short dash line position 24 in accordance with the inner surface shape of the chamfered surface 2a and the non-chamfered surface (outer surface) 2c below the notch portion 1a. become. At the time of this polishing, a polishing liquid is supplied to the notch portion 1a by a polishing liquid supply means (not shown).

As described above, the notch polishing wheel 24 having an outer peripheral shape substantially similar to the notch shape is urged against the notch portion 1a of the wafer W at the fixed position to press the notch portion 1a. The polishing wheel 24 is rotated around its axis and reciprocated in a direction perpendicular to the wafer surface of the wafer W. As a result, the notch portion polishing wheel 24 advances and retreats in the radial direction of the wafer W along the inner surface shape while pressing the inner surface of the notch portion 1a with a constant pressure, so that the lower chamfered surface 2a and the non-chamfered surface 2c Mirror surface processing can be performed favorably over the entire area.

Further, since the wafer W is not moved during the polishing, the wafer W is not deformed by the conventional inertial force. Moreover, since only the notch portion polishing wheel 24 is moved, expensive timing adjusting means is not required as compared with a conventional device in which the wafer W and the notch portion polishing wheel 24 are moved in synchronization with each other. Costs are reduced.

As described above, when the polishing of the chamfered surface 2a and the non-chamfered surface 2c below the notch portion 1a is completed, the polishing arm 19 is rotated counterclockwise about the fulcrum 19a by the polishing pressure applying cylinder 18. Thereby, the notch portion polishing wheel 24 is separated from the wafer W, and further, the polishing unit advance / retreat cylinder 6 is operated to move the notch portion polishing unit 7 at the polishing position (solid line) to the opposite side (see FIG. (1 center left direction) and hold it at the retracted position (two-dot chain line).

Next, the process proceeds to a step of polishing the outer peripheral chamfered surface 2d and the outer peripheral non-chamfered surface 2f (outer surface) of the wafer W by the outer peripheral polishing drum 30 and the outer peripheral polishing disk 31. That is, as shown in FIGS. 3 and 6, first, the outer peripheral polishing drum 30 is driven from below the wafer W by driving the drum linear motion unit of the drum driving means 36, and the outer peripheral chamfering of the wafer W in a holding state is performed. Move to the surface 2d side. Further, the pressing air cylinder or the like of the drum driving means 36 is operated, and the polishing cloth 34 for chamfering the outer peripheral polishing drum 30 is brought into contact with the outer peripheral chamfering surface 2d of the wafer W in a pressed state with a predetermined pressing force.

On the other hand, as shown in FIGS. 3 and 7, the outer peripheral polishing disk 31 is held by the disk driving means 38 from the side of the wafer W on the outer peripheral non-chamfered surface 2 of the wafer W.
f and brought into contact with the pressed state with a predetermined pressing force.

In this state, the polishing liquid is supplied to the polishing cloth 34 for the chamfered surface and the polishing cloth 37 for the outer side by the polishing liquid supply means.
The support rod 4 and the wafer suction disk 3 are rotated at a predetermined rotation speed by the rotation drive mechanism 39 while being supplied. Then, the outer peripheral chamfered surface 2d is polished by rotating the outer peripheral polishing drum 30 which is in contact with the outer peripheral chamfered surface 2d by the drum driving means 36. Also,
The outer peripheral polishing drum 30 is moved in the axial direction by driving the linear motion unit and the like of the drum driving means 36 so as to always contact the outer peripheral chamfered surface 2d during polishing.

Further, the outer peripheral polishing disk 3 which comes into contact with the outer peripheral non-chamfered surface 2f of the wafer W by the disk driving means 38.
1 is rotated to grind the outer peripheral non-chamfered surface 2f. Further, the outer peripheral polishing disk 31 is moved up and down by the disk driving means 38 while always abutting on the outer peripheral non-chamfered surface 2f during polishing. During polishing, the rotation angle of the wafer suction disk 3 is detected by the rotation angle detection sensor (not shown), and the wafer W is accurately rotated by 360 °, during which the entire circumference of the wafer W is polished.

As described above, the polishing apparatus of the present embodiment
Since the outer peripheral chamfered surface 2d and the outer peripheral non-chamfered surface 2f can be polished in addition to the notch portion 1a of the wafer W, the polishing productivity is extremely high. After the polishing process of one (lower) chamfered surface 2a and non-chamfered surface 2c of the notch portion 1a, and one (lower) outer chamfered surface 2d and outer non-chamfered surface 2f, the wafer W is cleaned with cleaning water. Sent to the process, after washing, again the other (upper) of the notch portion 1a
And the other (upper) outer peripheral chamfered surface 2e are polished.

[0042]

Since the present invention is configured as described above, it has the following effects. The invention according to claim 1 urges a notch portion grinding wheel whose outer peripheral shape substantially matches the notch portion shape against a notch portion of a wafer at a predetermined position so as to press the notch portion polishing wheel with a predetermined pressure. In this state, the notch polishing wheel is rotated about its axis and reciprocated in a direction substantially orthogonal to the wafer surface of the wafer. As a result, the notch polishing wheel advances and retreats in the radial direction of the wafer along the inner surface shape of the notch due to the reaction of the polishing pressure received from the notch, and satisfactorily polishes the inner surface of the notch with a constant polishing pressure. In addition to this, it is possible to satisfactorily mirror-process the vicinity of the wafer surface in the notch, and consequently to satisfactorily mirror the entire inner surface of the notch. In addition, since only the notch portion polishing wheel is moved without moving the wafer, inertial force does not act on the wafer during polishing, so that deformation of the wafer can be avoided.

According to the second aspect of the present invention, the polishing method of the first aspect can be easily implemented, and an expensive control system as in the related art for moving the notch portion polishing wheel is unnecessary.
The structure of the device is not complicated, and as a result, the cost of the device is not increased. In addition to the above-described effects, the invention according to claim 3 can reliably urge the notch polishing wheel to press against the notch portion of the wafer by using an inexpensive polishing pressure applying cylinder which is easy to maintain and inexpensive. Cost can be further reduced. According to the fourth aspect of the present invention, in addition to the above-described effects, a single polishing apparatus can polish not only the notch portion of the wafer but also the chamfered surface and the outer surface of the outer periphery, so that the productivity of polishing can be greatly improved. it can.

[Brief description of the drawings]

FIG. 1 is a front view showing a cross section of an exterior and the like in one embodiment of a wafer chamfering surface polishing apparatus of the present invention.

FIG. 2 is a left side view of FIG.

FIG. 3 is a schematic view of the inside of the apparatus viewed from the right in FIG.

FIG. 4 is a diagram showing a shape of an outer peripheral portion of a notch portion polishing wheel and a shape of a notch portion of a wafer.

FIG. 5 is a view showing a movement state of a notch portion polishing wheel when polishing a notch portion of a wafer in the present invention.

FIG. 6 is a view showing a state in which one chamfered surface of a wafer is being polished by a polishing drum.

FIG. 7 is a diagram showing a state in which a non-chamfered surface (end surface) of a wafer is polished by a polishing disk.

8A is an external perspective view of a wafer, FIG. 8B is an enlarged view of a notch portion of the wafer, and FIG. 8C is a diagram showing a state where the notch portion is polished by a polishing wheel.

FIG. 9 is a schematic view of a conventional wafer notch polishing apparatus.

FIG. 10A is a perspective view showing another example of a conventional notch polishing apparatus for a wafer, and FIG. 10B is a view showing a state in which the notch is polished by a polishing wheel of the polishing apparatus. .

[Explanation of symbols]

 W wafer 1 device main body 1a notch 2 device exterior 2a, 2b chamfered surface 2c non-chamfered surface (outer surface) 2d, 2e outer chamfered surface 2f outer non-chamfered surface (outer surface) 3 wafer suction disk 4 support rod 5 wafer holding mechanism Reference Signs List 6 Polishing unit advance / retreat cylinder 6a Rod 7 Notch portion polishing unit 8 Polishing unit support bracket 9 Slide mechanism 10 Connecting member 11 Polishing unit main body 12 Lifting motor 12a Rod 13 Coupling 14 Ball screw shaft 15 Lifting member 16 Guide shaft 17 Cylinder bracket 18 Polishing pressure application cylinder 18a Rod 19 Polishing arm 19a Intermediate portion (fulcrum) 20 Pin member 21 Fixed bracket 22 Polishing wheel support member 23 Polishing motor 23a Rotating shaft 24 Notch portion polishing wheel 25 Cover member 26 Bellows Reference Signs List 27 discharge pipe 28 urging mechanism 29 reciprocating movement mechanism 30 outer peripheral polishing drum (outer peripheral chamfering polishing member) 31 outer peripheral polishing disc (outer peripheral non-chamfering polishing member) 32 drum rotating shaft member 33 drum body 34 polishing cloth for chamfering surface 35 Disk body 36 Drum drive means 37 Non-chamfered polishing cloth 38 Disk drive means

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Akira Higuchi 985 Ino, Ginya, Ikuno-cho, Asago-gun, Hyogo Pref.

Claims (4)

[Claims] 1. A wafer having a chamfered outer peripheral edge and a notch is held at a fixed position, and an outer peripheral portion of a notch polishing wheel that intersects with the wafer is fixed to the held notch of the wafer. A method for polishing a chamfered surface of a wafer, comprising: reciprocating in a direction substantially orthogonal to the wafer surface of the wafer while rotating the notch portion polishing wheel about its axis while urging to press with a pressure of . 2. A wafer holding mechanism for holding a wafer having a chamfered outer peripheral edge and a notch at a fixed position, a notch polishing wheel arranged to intersect with the wafer and rotated around an axis. An urging mechanism for holding the notch portion polishing wheel, and urging the notch portion polishing wheel so that an outer peripheral portion thereof presses the notch portion of the wafer with a predetermined pressure; and A reciprocating mechanism for driving the notch portion polishing wheel to reciprocate in a direction substantially orthogonal to the wafer surface of the wafer. 3. The polishing apparatus for chamfering a wafer according to claim 2, wherein the biasing mechanism includes a polishing pressure applying cylinder driven by the reciprocating mechanism and the notch polishing wheel at one end. The other end is rotatably connected to the rod of the polishing pressure applying cylinder,
And a polishing arm having an intermediate portion rotatably supported as a fulcrum. 4. The wafer chamfering surface polishing apparatus according to claim 2, wherein a rotation mechanism for rotating the wafer holding mechanism around an axis of the wafer, an outer peripheral chamfering surface and an outer periphery of the wafer. An apparatus for polishing a chamfered surface of a wafer, comprising: an outer peripheral chamfered polishing member and an outer peripheral non-chamfered polishing member for polishing the non-chamfered surface, respectively.