JP2000317790A - Chamfered face polishing device for semiconductor wafer and its method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To efficiently polish a chamfered face by providing a semiconductor wafer tilting mechanism tilting a semiconductor wafer in parallel with the rotary shaft of a notch polishing wheel around the vicinity of the portion where an outer periphery polishing drum abuts on the outer periphery of the semiconductor wafer. SOLUTION: A semiconductor wafer W is tilted by a semiconductor wafer tilting mechanism 80 so that the abutted portion between the inner face of a notch section V and a notch abrasive cloth 39 is separated from the reference line perpendicularly connecting the tilt axis of the semiconductor wafer W and the rotary shaft of a notch polishing wheel 23. A notch polishing wheel rotation drive section 24 rotates the notch polishing wheel 23 forward or reversely to move the notch abrasive cloth 39 at the abutted portion toward the reference line. The surface of the notch abrasive cloth 39 at the abutted portion is rotated toward the reference line, i.e., toward the uppercut side (biting side), for polishing.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus and a method for polishing a chamfered surface of a semiconductor wafer for polishing a chamfered surface of a notch portion and an outer peripheral portion of the semiconductor wafer.

[0002]

2. Description of the Related Art As a technique of etching (etching) a chamfered surface formed on a peripheral edge of a semiconductor wafer such as a silicon wafer, a CCR (Chemical Corne) is used.
r Rounding) processing is known.
When CR processing is performed, projections are formed at the boundary between the chamfered surface and the front and back surfaces of the semiconductor wafer. These projections are minute, but when the semiconductor wafer is housed in a resin cassette, the semiconductor wafer comes into contact with the cassette and scrapes the cassette, resulting in minute shavings. It goes without saying that the shavings cause the performance of the semiconductor wafer to deteriorate.

Therefore, apart from the CCR processing, the chamfered surface of the semiconductor wafer is subjected to CMP (Chemical Mecha).
It is known to perform a process such as a mechanical polishing process. This CMP processing is a technique of polishing with a polishing cloth while supplying a polishing liquid toward a chamfered surface of a semiconductor wafer. Conventionally, as an apparatus for performing this CMP processing, as shown in FIG. The wound polishing drum D is chamfered to the outer peripheral portion S, M of the semiconductor wafer W.
Polishing was performed by pressing against and rotating.

However, this CMP processing apparatus includes:
The following issues remain. Conventionally, in a semiconductor wafer, a linear notch called an orientation flat is formed in a part of an outer peripheral portion thereof for alignment and orientation in pattern formation of a semiconductor integrated circuit by photolithography technology, This part has been used as a reference for positioning and azimuth alignment. When this orientation flat is formed on a semiconductor wafer, the outer peripheral portion of the semiconductor wafer is linearly cut out, so the notch amount of the semiconductor wafer is inevitably increased, and accordingly, a semiconductor chip that can be formed by one semiconductor wafer And the number of semiconductor wafers is reduced, so that expensive semiconductor wafers cannot be used efficiently. Further, in a device such as a spin dryer that dries a semiconductor wafer by centrifugal force due to high-speed rotation, there is a problem that it is difficult to balance a large-diameter wafer with an orientation flat. Therefore, recently, a notch V which is an arc-shaped or V-shaped notch as shown in FIG. 17 is provided in a part of the outer peripheral portion of the semiconductor wafer, and the positioning of the semiconductor wafer W is performed using the notch V. And those that perform azimuth alignment have been put to practical use. The notch portion V is formed using, for example, a grindstone T having a spindle shape as shown in FIG. That is, the notch portion V is formed by cutting the grinding wheel T into the outer peripheral portion of the semiconductor wafer W and grinding a part of the outer peripheral portion of the semiconductor wafer W. As shown in FIG. The inner surface of V has a shape swelling outward from the center in the thickness direction of the semiconductor wafer W. However, the above C
In the MP processing, there is a problem that only the tip side chamfering surface S and the front and back side chamfering surfaces M in the outer peripheral portion of the semiconductor wafer W can be polished, and the inner surface of the notch V cannot be polished.

In order to polish the inner surface of the notch V, there are, for example, those disclosed in Japanese Patent Nos. 2798345 and 2798347. As shown in FIG. 20, the polishing apparatus 141 in Japanese Patent No. 2798345 includes a table 143 for holding a semiconductor wafer W, and a pulse motor 142 capable of rotating and pulsating the table 143 in forward and reverse directions. Yes,
A rotary buff (notch polishing cloth) 144 supported by the link mechanism 146 and connected to the electric motor 145 is rotatable about an axis parallel to the surface of the semiconductor wafer W. Further, the distal end side of the substrate 161a of the link 161 branches in a bifurcated manner, and one of the branches is held by a bearing 147, and the other is connected to a pulse motor 148. Here, the center axis of the bearing 147 and the rotation axis of the pulse motor 148 exist on the same straight line, and a line connecting the centers thereof is parallel to the surface of the semiconductor wafer W and substantially at the notch V of the semiconductor wafer W. Being in contact. Further, a link 162 is attached to the blanket 161b so as to be able to perform a seesaw operation around the shaft 162a.
An air cylinder device 149 is provided between the other end of the link 161 and the rear end of the link 161. Link 161 and Link 1
62 can be operated separately. Then, the air cylinder device 149 is operated to press the rotating buff 144 against the inner surface of the notch V of the semiconductor wafer W, rotate the rotating buff 144 by the electric motor 145, and move the inner surface of the notch V by the pulse motor 148. Then, the notch V is polished.

Alternatively, as shown in FIGS. 21 and 22,
The polishing apparatus 151 in Japanese Patent No. 2798347 includes a table 152 for holding a semiconductor wafer W, a pulse motor 153 for rotating the table 152, and a table 1
52, and a crankshaft 154a.
155 and a pulse motor 156 connected to the motor. Here, the crankshaft 154a is configured so as to be parallel to the main surface of the semiconductor wafer W, and such that an extension thereof substantially contacts the notch V of the semiconductor wafer W. The rotating buff (notch polishing cloth) 157 is connected to the electric motor 158,
92 are held by a link mechanism 190. The link mechanism 190 is provided on the substrate 191a of the link 191.
A link 192 is attached to a blanket 191b standing upright so as to be able to perform a seesaw operation around a shaft 192a, and upper ends of the links 191 and 192 are connected by an air cylinder device 200. Then, the air cylinder device 200 is operated to press the rotary buff 157 against the inner surface of the notch V of the semiconductor wafer W, rotate the rotary buff 157 by the electric motor 158, and move the rotary buff 157 along the inner surface of the notch V by the pulse motor 156. Then, the notch V is polished.

[0007]

SUMMARY OF THE INVENTION Such a polishing apparatus 1
When the notch portion V is polished by 41 and 151, the rotation direction of the rotating buffs 144 and 157 is not rotated toward the upper cut side (biting side) with respect to the tilted semiconductor wafer W as shown in FIG. And the rotating buff 1
As shown in FIG. 24, a burr B (whisker) is provided at 44 (157).
Tends to occur. That is, the notch V formed so as to be narrower inward is formed by polishing the buff 144 (1).
When the polishing is performed according to 57), the notch V and the end of the polishing buff 144 (157) interfere with each other as shown by the hatched portion in FIG. 24A, and as shown in FIG.
The tip of (157) is peeled off, causing burrs B. Therefore, polishing unevenness occurs in the notch portion V, and satisfactory polishing cannot be performed. Here, the upper cut side refers to a state in which the inner surface of the notch V is rubbed and polished by the rotating buff 144 (157) rotating so that the inner side of the notch V is cut from the side of the outer peripheral portion of the outer peripheral portion of the semiconductor wafer W. ,
As shown in FIG. 23A, when the front-side chamfered surface S of the semiconductor wafer W faces upward, the rotating buff 144 (1
57) rotates counterclockwise as indicated by arrow Y, and FIG.
(B) As shown in FIG.
Is facing downward, the rotating buff 144 (157)
Means clockwise rotation as indicated by arrow Y '.

[0008] However, the above polishing apparatus 14
1 (151), the polishing buff 14
4 (157), that is, as shown in FIG. 25, in a state where the tilt axis G2 of the semiconductor wafer W is located near the contact portion between the notch V and the rotating buff 144 (157). When the polishing buff 144 (157) is rotated toward the upper cut side with respect to the semiconductor wafer W, chatter vibration and the like are generated in the semiconductor wafer W, so that not only stable polishing cannot be performed, but also the semiconductor wafer W is adversely affected. Will affect you.

Further, when polishing the chamfered surfaces S, M, etc. of the outer peripheral portion of the semiconductor wafer W, in a conventional method such as a CMP process as shown in FIG. In addition, not only problems such as an increase in the size of the entire apparatus and an increase in the processing time occur, but also both sides must be held by a chuck in order to hold the semiconductor wafer W, and chuck flaws and the like occur. A problem arose.

The present invention has been made in view of such circumstances, and a semiconductor wafer chamfering surface polishing apparatus and method capable of efficiently polishing all chamfered surfaces including notch portions of a semiconductor wafer. It is intended to provide.

[0011]

In order to solve the above-mentioned problems, the invention according to claim 1 is directed to a semiconductor wafer chamfering surface polishing apparatus for polishing a chamfered surface of a notch portion and an outer peripheral portion of a semiconductor wafer. A semiconductor wafer rotation mechanism for rotating the semiconductor wafer held by the wafer suction disk; a disk-shaped or annular ring having a cross-sectional shape of a peripheral portion substantially similar to a notch portion; A notch polishing wheel provided with a notch polishing cloth, a notch polishing wheel rotating mechanism that rotatably supports the notch polishing wheel while pressing a peripheral edge of the notch polishing cloth against an inner surface of the notch portion. A cylindrical outer peripheral polishing drum disposed at a position facing the notch polishing cloth with respect to the semiconductor wafer; An outer peripheral polishing drum rotating mechanism that rotatably supports a polishing drum while abutting the outer peripheral portion chamfering surface of the semiconductor wafer, and a semiconductor wafer held by the wafer suction disk, and a rotating shaft of the notch polishing wheel. A semiconductor wafer tilting mechanism for tilting around a portion near the portion where the outer peripheral polishing drum is in contact with the outer peripheral polishing drum and the outer peripheral portion of the semiconductor wafer.

According to the present invention, the semiconductor wafer held by the wafer suction disk is parallel to the rotation axis of the notch polishing wheel, and the outer peripheral polishing drum is in contact with the outer peripheral portion of the semiconductor wafer. The notch portion is tilted about the vicinity of the portion, and the notch portion is polished by a notch polishing cloth provided on a notch polishing wheel rotated by the notch polishing wheel rotating mechanism. The notch portion V is polished to the notch polishing cloth while tilting, so that the inner surface is entirely polished.

An outer peripheral polishing drum for polishing an outer peripheral portion of the semiconductor wafer is disposed at a position facing the notch polishing wheel with respect to the semiconductor wafer, and the semiconductor wafer is centered on the tilt axis. And the outer peripheral polishing drum and the outer peripheral chamfered surface of the semiconductor wafer are brought into contact with each other for polishing. It is only necessary to tilt the semiconductor wafer by the tilt mechanism. That is, even when polishing each chamfered surface on the front and back sides or the front end side of the outer periphery of the semiconductor wafer, the step of inverting the entire semiconductor wafer is not required, and the polishing of each chamfered surface can be continuously performed at once. . Therefore, the number of polishing steps and time can be reduced, and the contact angle between the outer peripheral polishing drum and the chamfered surface of the outer peripheral portion of the semiconductor wafer can be set arbitrarily, so that it is flexible for polishing semiconductor wafers of various specifications. Can respond. Further, since it is no longer necessary to reverse the semiconductor wafer, the support of the semiconductor wafer during polishing may be performed on either the front or back surface, for example, holding by a chuck or the like can be minimized, The occurrence of scratches and the like due to holding can be reduced.

Further, since the notch polishing wheel and the outer peripheral polishing drum are arranged so as to face each other with respect to the semiconductor wafer, a transport mechanism and the like between the notch portion polishing step and the outer peripheral chamfering surface polishing step are omitted. In addition, the size of the apparatus can be reduced and the number of steps can be reduced. In addition, since the polishing of each chamfered surface of the semiconductor wafer outer peripheral portion is performed by the same mechanism, work efficiency can be improved, and space saving of the entire apparatus can be realized, cost reduction, and reduction of each chamfered surface. Stable polishing can be performed.

According to a second aspect of the present invention, there is provided the apparatus for polishing a chamfered surface of a semiconductor wafer according to the first aspect, wherein the notch polishing wheel is tilted by the semiconductor wafer tilting mechanism. A notch polishing wheel advancing / retracting mechanism for moving the semiconductor wafer in the separating direction so as to always exert a constant pressing force of the notch polishing cloth against the inner surface of the notch portion. .

According to the present invention, since the notch polishing wheel can be moved in the direction of separation and contact with respect to the notch portion of the tilted semiconductor wafer, the pressing of the notch polishing cloth against the inner surface of the notch portion can be performed. The pressure can be set arbitrarily while constantly acting. Therefore, a uniform pressing force can be applied to the inner surface of the notch portion, and stable polishing without unevenness can be performed. Further, during the outer peripheral chamfering polishing step, the semiconductor wafer is retracted from the vicinity of the semiconductor wafer.

According to a third aspect of the present invention, there is provided the apparatus for polishing a chamfered surface of a semiconductor wafer according to the first or second aspect, wherein the semiconductor wafer tilting mechanism causes the semiconductor wafer to be notched with the inner surface of the notch. When the contact portion with the polishing cloth is tilted away from a reference line that connects the tilt axis of the semiconductor wafer and the rotation axis of the notch polishing wheel at right angles, the notch polishing wheel The rotation mechanism is characterized in that the notch polishing wheel rotated forward and backward is rotated in one direction in which the surface of the notch polishing cloth at the contact portion is directed to the reference line.

According to the present invention, the semiconductor wafer is:
The contact portion between the inner surface of the notch and the polishing cloth for the notch is tilted away from a reference line that connects the tilt axis of the semiconductor wafer and the rotation axis of the polishing cloth for the notch at right angles. Then, the notch polishing cloth is rotated forward and backward so that the surface at the contact portion is directed to the reference line. That is, the notch polishing cloth is rotated to the biting side (upper cut side). Therefore, no burrs are generated at the end of the notch polishing cloth, and uneven polishing can be eliminated. Also,
Even if burrs are generated, the notch polishing cloth is rotated toward the upper cut side, so that the generated burrs are cut naturally, and the notch polishing cloth is less likely to generate burrs. The tilt axis of the semiconductor wafer at this time is parallel to the rotation axis of the notch polishing wheel, and is provided near a portion where the outer peripheral polishing drum and the outer peripheral portion of the semiconductor wafer are in contact with each other, that is, It is set far from a contact portion between the notch portion and the polishing cloth for the notch. Therefore, even if the notch polishing cloth is rotated to the upper cut side, the action of vibrations and moments that adversely affect the semiconductor wafer W, such as chatter vibration, is reduced. Is polished stably.

According to a fourth aspect of the present invention, there is provided the apparatus for polishing a chamfered surface of a semiconductor wafer according to any one of the first to third aspects, wherein the outer peripheral polishing drum is provided with the polishing drum in a rotational axis direction. A polishing drum linear movement mechanism for reciprocating movement and a polishing drum advancing / retreating mechanism for moving in a direction of contacting and separating from the semiconductor wafer are provided.

According to the present invention, the outer peripheral polishing drum is configured to polish the outer peripheral chamfered surface while reciprocating in the rotation axis direction. Therefore, the wear of the surface of the outer peripheral polishing drum is not uneven, and the polished surface of the outer peripheral chamfered surface is uniform and favorable. The outer peripheral polishing drum is movable in the direction of coming and going from the semiconductor wafer, and is retracted during the notch portion polishing step. Further, the pressing force against the outer peripheral chamfered surface can be arbitrarily set.

According to a fifth aspect of the present invention, there is provided the apparatus for chamfering a chamfered surface of a semiconductor wafer according to any one of the first to fourth aspects, wherein a thickness of the notch polishing cloth is set to a width in a circumferential direction of the notch. In addition to providing a smaller size, the semiconductor wafer rotating mechanism includes a servomotor that swings the wafer suction disk in a circumferential direction while the notch polishing cloth is in contact with the inner surface of the notch. It is characterized by.

According to the present invention, the thickness of the notch polishing cloth is set smaller than the circumferential width of the notch.
The end of the notch polishing cloth and the notch do not interfere with each other, and the occurrence of burrs of the notch polishing cloth is reduced. Then, by rotating the semiconductor wafer in the circumferential direction while the notch polishing cloth is kept in contact with the notch portion, the inside of the notch portion is polished stably as a whole.

According to a sixth aspect of the present invention, there is provided the apparatus for polishing a chamfered surface of a semiconductor wafer according to any one of the first to fourth aspects, wherein the thickness of the polishing cloth for the notch is set to a width in a circumferential direction of the notch. Along with providing the notch, the notch polishing wheel is provided with a notch polishing wheel swinging mechanism that reciprocates in the rotation axis direction while the notch polishing cloth is in contact with the inner surface of the notch. Features.

According to the present invention, by providing the thickness of the polishing cloth for the notch to be smaller than the circumferential width of the notch, the end of the polishing cloth for the notch and the notch do not interfere with each other. Generation can be reduced, and as a result, polishing unevenness can be reduced. By supporting the polishing cloth for the notch so as to be reciprocally movable in the direction of the rotation axis, the inner surface of the notch is entirely uniformly polished.

According to a seventh aspect of the present invention, there is provided a method for polishing a chamfered surface of a semiconductor wafer for polishing a chamfered surface of a notch portion and an outer peripheral portion of the semiconductor wafer, the method comprising: A semiconductor wafer, a notch polishing wheel provided with a disc-shaped or annular notch polishing cloth whose peripheral edge shape is substantially rotatable in the forward and reverse directions and whose peripheral portion is substantially similar to the notch portion shape, and a rotatably supported cylindrical shape. Arranged so as to be able to contact each other between the outer peripheral polishing drum, the semiconductor wafer held by the wafer suction disk, parallel to the rotation axis of the notch polishing wheel,
In addition, while tilting around the portion where the outer peripheral polishing drum and the outer peripheral portion of the semiconductor wafer are in contact with each other as an axis, the contact portion between the inner surface of the notch and the polishing cloth for the notch is tilted by the tilt axis of the semiconductor wafer. And the rotation axis of the notch polishing wheel are perpendicular to each other, the tilting wheel is tilted away from the reference line, the notch polishing wheel, the contact portion of the notch polishing cloth surface the reference line So that the peripheral edge of the notch polishing cloth is pressed against the inner surface of the notch portion and rotated forward and reverse around an axis in a direction perpendicular to the axis of the semiconductor wafer, and the notch portion with respect to the inner surface. The entire inner surface of the notch portion is polished by moving the semiconductor wafer in the direction of contact and separation so that the pressing force of the polishing cloth for the notch acts in the vertical direction, and then the semiconductor wafer is polished. While rotating the wafer, the semiconductor wafer is tilted at a predetermined angle, and the semiconductor wafer is reciprocated in the rotation axis direction while rotating the outer peripheral polishing drum about an axis perpendicular to the rotation axis of the notch polishing wheel. A plurality of chamfered surfaces of the outer peripheral portion are continuously polished by contacting one chamfered surface of the outer peripheral portion of the wafer and polishing the outer peripheral chamfered surface, and changing a tilt angle of the semiconductor wafer. A method for polishing a chamfered surface of a semiconductor wafer.

According to the present invention, the inner surface of the notch is polished by
It is performed stably and uniformly while suppressing burrs of the notch polishing cloth and reducing adverse effects such as vibration and moment on the semiconductor wafer. And since the outer peripheral polishing drum is arranged at the position facing the notch polishing cloth, the semiconductor wafer is held by one wafer suction disk, and the polishing of the inner surface of the notch portion and the polishing of the outer peripheral chamfer surface are continuously performed. It can be carried out. Further, since the semiconductor wafer is tilted, the respective chamfered surfaces on the front and back sides of the outer peripheral portion can be continuously polished, so that space-saving and efficient polishing can be performed.

[0027]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an apparatus and a method for chamfering a semiconductor wafer according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a plan view showing an apparatus for polishing a chamfered surface of a semiconductor wafer according to the present invention.

The polishing apparatus 4 for chamfering a semiconductor wafer W according to the present invention is disposed downstream of the wafer positioning unit 2 in the entire polishing apparatus system P shown in FIG. That is, the polishing apparatus system P includes a wafer removal mechanism 1 for removing the semiconductor wafer W from the removal cassette C1, a wafer positioning unit 2 for positioning the semiconductor wafer W removed from the wafer removal mechanism 1, and a wafer positioning unit 2 Chamfering surface polishing apparatus 4 for receiving a semiconductor wafer W from each other and polishing each chamfered surface S, M such as a notch portion V and front and back surfaces.
And a wafer transport mechanism 3 for transporting the semiconductor wafer W from the wafer positioning unit 2 to the chamfering surface polishing apparatus 4.

In the polishing apparatus system P of this embodiment, a wafer cleaning mechanism (not shown) for cleaning the polished semiconductor wafer W is further downstream of the chamfering polishing apparatus 4. A wafer storage mechanism for storing the washed semiconductor wafer W in a storage cassette, and each of these mechanisms and devices includes:
It is electrically controlled by the operation control unit 5.

In FIG. 10, a wafer take-out mechanism 1 is provided.
Is a take-out cassette C1 placed on the upper surface of the base 6.
And a loader unit 8 provided on the base 6 for sucking the semiconductor wafers W from the unloading cassette C1 with the unloading hand 7, extracting the wafers one by one, and transferring them to the wafer positioning unit 2.

The unloading cassette C1 is placed so that a plurality of stored semiconductor wafers W are placed in a horizontal state, and the unloading cassette C1 is installed so that the unloading direction of each semiconductor wafer W is directed to the loader unit 8. Further, the loader unit 8 arranges the take-out hand 7 in a horizontal state, and the take-out hand 7 is rotatable in a horizontal direction and is movable forward and backward in a radial direction.
Furthermore, it is supported so that it can move up and down.

The wafer positioning unit 2 is provided on the base 6 adjacent to the take-out cassette C1, receives the semiconductor wafer W taken out of the take-out cassette C1 from the loader unit 8, and centers the semiconductor wafer W on the mounting table 9. And the direction of the notch V is determined.

The wafer positioning unit 2 includes a mounting table 9
A centering mechanism 10 for centering the upper semiconductor wafer W, a mounting table rotating mechanism provided below the mounting table 9 for rotating the mounting table 9, and a notch positioning mechanism for determining the direction of the notch V are provided. ing. The mounting table rotating mechanism is supported by a plurality of support columns, and can be moved up and down together with the support columns by a driving source (not shown) connected to these support columns.

The wafer transfer mechanism 3 includes a transfer unit 11 that transfers the semiconductor wafer W positioned by the wafer positioning unit 2 to the chamfering surface polishing apparatus 4 at the transfer unit 10. The transfer unit 11 is a hand unit 12 that sucks and supports the semiconductor wafer W by a suction groove 12 a formed at the tip end, and the hand unit 12 is horizontally movable between the wafer positioning unit 2 and the transfer unit 10. The apparatus includes a rodless cylinder 13 for supporting and a vertically moving cylinder for supporting the hand unit 12 so as to be vertically movable. The hand portion 12 has a distal end portion formed in a substantially arc shape, and is installed so as to extend horizontally in a direction oblique to the extending direction of the rodless cylinder 13.

The rodless cylinder 13 is supported by a beam member 14 fixed horizontally to a column member erected on the base 6, and is disposed from above the wafer positioning unit 2 to above the transfer unit 10. ing.

As shown in FIGS. 1 to 3, the chamfered surface polishing apparatus 4 includes a side plate 15, a top plate 16, a shutter 17, and a bottom plate 18. The bottom plate 18 is shown in FIG.
As shown in the figure, the polishing liquid is set to be inclined toward the center, and a polishing liquid drain hole 15a for discharging the polishing liquid used at the time of polishing is formed at the lowermost portion.

The top plate 16 is arranged so as to cover the upper side of the chamfering polishing device 4, and a circular top plate opening 16a having an inner diameter slightly larger than the outer diameter of the semiconductor wafer W is provided at the center thereof. Is formed. Further, the top plate 16 includes a pair of shutter air cylinders 19 supported on the upper side of the one side plate 15 so as to be extendable and contractible in the horizontal direction. A pair of plate-shaped shutters 17 are respectively fixed via members 20.

A through hole is formed in the shutter connecting member 20, and a guide rod 21 provided on the top plate 16 is formed in the through hole.
Is inserted. That is, it is supported by the shutter connecting member 20 and the guide bar 21 so as to be horizontally movable. These shutters 17 are arranged along the top plate 16 so as to cover the chamfering surface polishing device 4, and are supported by the top plate 16 so that they can be opened and closed by expansion and contraction of a shutter air cylinder 19.

The pair of shutters 17 have semicircular cutouts 17a formed at inner edges facing each other, and a circular opening is formed at the center when the shutter is closed.

The chamfered-surface polishing device 4 holds the semiconductor wafer W held by the suction disk 22 in the chamfered-surface polishing device 4.
And a notch polishing wheel 23 that is rotatably supported with an axis parallel to the front and back surfaces of the semiconductor wafer W and that is rotatably supported by the notch polishing wheel 23 that rotationally drives the notch polishing wheel 23 A rotation drive unit (notch polishing wheel rotation mechanism) 24, and the notch polishing wheel rotation drive unit 24 is moved together with the notch polishing wheel 23 in the vertical direction and the notch polishing wheel 23 is moved toward and away from the semiconductor wafer W. A notch polishing wheel swing drive unit (notch polishing wheel advance / retreat mechanism) 25;
Notch polishing liquid supply means 26 that supplies a polishing liquid to the notch polishing wheel 23 and also supplies the polishing liquid to the notch portion V of the semiconductor wafer W during polishing.

The notch polishing wheel swing drive unit 25 includes:
The oscillating motor 2 fixed to the base 6 by an oscillating portion support plate 27 and having a rotating shaft fixed to the oscillating portion support plate 27 in a horizontal state.
8, a rotation drive unit support plate 29 fixed to the rotation shaft of the swing motor 28, a notch pressing cylinder 30 having one end connected to the rotation drive unit support plate 29, and a rotation drive unit support plate 2.
9, a connection support member 31 supported movably in the radial direction and connected to the tip of a notch pressing cylinder 30.
And

The notch polishing wheel rotation drive unit 24
A cylindrical main body 32 fixed to the end of the connecting support member 31 in a state parallel to the rotation axis of the swing motor 28; a rotating motor 33 fixed to the rear end of the cylindrical main body 32; And a wheel shaft member 34 rotatably inserted into the cylindrical main body 32 and having a rear end connected to the rotation shaft. The notch polishing wheel 23 is attached to the tip of the wheel shaft member 34. When the notch pressing cylinder 30 is driven, the cylindrical body 32 pivots in the horizontal direction, and the notch polishing wheel 23 attached to the tip of the cylindrical body 32 moves in the direction of approaching and separating from the semiconductor wafer W. It has become.

The notch polishing wheel rotation drive unit 2
4 is arranged in a protruding state into the chamfering surface polishing device 4 from a driving part insertion hole 15b formed in the side plate 15 and a cylindrical body 32 is provided between the periphery of the driving part insertion hole 15b and the cylindrical body 32.
A cylindrical body cover 35, such as a bellows, is attached to cover the outer peripheral portion of the grinding wheel to prevent the polishing liquid from adhering to the notch polishing wheel rotation drive unit 24 and scattering outside the chamfering surface polishing apparatus 4.

The notch polishing wheel 23 includes a fixing member 36 fixed to the tip of a wheel shaft member 34 and a wheel body 37 attached to the fixing member 36 and arranged coaxially with the wheel shaft member 34. A wheel cover 38 is provided so as to cover the wheel main body 37 except for a part of the wheel main body 37. A ring-shaped notch polishing cloth 39 is attached to an outer peripheral portion of the wheel body 37, and the notch polishing cloth 39 is attached to the wheel body 3.
7 is set to be larger than the outer diameter of the wheel main body 37 so as to protrude from the outer edge of the wheel body 7 by a predetermined amount.

The notch polishing liquid supply means 26 is connected to an external polishing liquid supply source (not shown), and is provided with a polishing liquid supply nozzle 26 arranged from the side plate 15 toward the notch polishing cloth 39.
a. That is, at the time of polishing, the polishing liquid is spouted from the tip of the polishing liquid supply nozzle 26a toward the notch polishing cloth 39 and supplied to the notch polishing cloth 39 and the notch portion V.

A rotatable notch polishing cloth cover shaft member 40 parallel to the cylindrical body 32 is provided below the chamfered surface polishing device 4. A notch polishing cloth cover 41 is fixed at its end. That is, the notch polishing cloth cover 4 is rotated by rotating the notch polishing cloth cover shaft member 40.
1 can be rotated.

As shown in FIGS. 4, 5, 6, and 7, a cylindrical shape for polishing the outer peripheral portion of the semiconductor wafer W is provided at a position facing the wheel body 37 with respect to the semiconductor wafer W. Is disposed. The outer peripheral polishing drum 50 is disposed on the side of the semiconductor wafer W held by the suction disk 22 so that the outer peripheral polishing drum 50 can contact the outer peripheral portion of the semiconductor wafer W. It is designed to be rotated about an axis in a direction orthogonal to the center.

The outer peripheral polishing drum 50 has a polishing drum rotating mechanism 51 for driving the outer peripheral polishing drum 50 to rotate.
a, a polishing drum linear movement mechanism 51b for linearly reciprocating in the rotation axis direction of the outer peripheral polishing drum 50, and a polishing drum advance / retreat mechanism 51c for moving the outer peripheral polishing drum 50 in a direction of approaching / separating from the semiconductor wafer W. Outer peripheral polishing drum driving means 51 comprising: a polishing liquid supplying means for supplying a polishing liquid onto the outer peripheral polishing drum 50 during polishing and also supplying the polishing liquid to the outer peripheral chamfered surfaces S and M of the semiconductor wafer W; And each is provided.

The polishing drum linear motion mechanism 51b is
This polishing drum linear motion mechanism 51b is swingably supported,
An outer peripheral polishing drum support portion 53 that rotatably supports the outer peripheral polishing drum 50 at its tip is provided.

The polishing drum linear motion mechanism 51b is fixed on the base 6, and is parallel to the surface of the notch polishing wheel 23.
That is, a unit body 57 having a guide 55 provided in the vertical direction, a cam follower rotation motor 56 for rotating the cam follower 54 attached to the tip of the rotating shaft,
A linear motion portion 58 is connected to the unit main body 57 by the guide 55 so as to be movable along the guide 55.

That is, when the cam follower rotation motor 56 is driven to rotate the cam follower 54 about the rotation center C of the cam follower rotation motor 56 as shown in FIG. When the cam follower 54 rotates in the inside of the guide 58a, the linear
5 is set to swing.

The polishing drum supporting portion 53 makes the outer peripheral polishing drum 50 abut against the outer peripheral chamfered surfaces S and M of the semiconductor wafer W in a pressed state, and in the vertical direction (parallel to the surface of the notch polishing wheel 23). That is, when each chamfered surface S, M of the tilted semiconductor wafer W is brought into contact with the surface of the outer peripheral polishing drum 50, the semiconductor wafer W is set so as to be slidable in the radial direction of the semiconductor wafer W. .

That is, the polishing drum supporting portion 53 is substantially T
Swing shaft portion 59 formed in a linear shape and provided in linear motion portion 58
Arm 60 pivotally supported on the arm, and a swing arm 60
And a drum rotation motor 61 installed at the base end of the drum.

The swing arm 60 has a through hole 60b formed in an intermediate projecting portion 60a, and the swing shaft 59 is formed in the through hole 60b.
And is swingably supported. At the tip of the swing arm 60, an arm cylindrical portion 60c that rotatably supports the drum support shaft 62 by inserting the drum support shaft 62 is provided.
3 is provided with an axis in the linear motion direction.

The drum support shaft portion 62 is installed in a direction perpendicular to the rotation axis of the notch polishing wheel 23, that is, vertically upward. A drum pulley 63 is fixed to a base end, and an outer periphery is Polishing drum 50 is coaxially mounted.

A motor-side pulley 64 is fixed to the rotation shaft of the drum rotation motor 61, and the motor-side pulley 64 and the drum-side pulley 61 are connected by an endless belt 65.

Polishing drum linear motion mechanism 51b and swing arm 60
The supporting members 66a and 66b are connected to each other by a swinging air cylinder 67 disposed horizontally. By expanding and contracting the swing air cylinder 67, the outer peripheral polishing drum support 53 can be swung in the horizontal direction about the swing shaft 59. That is, the outer peripheral polishing drum 50 can be moved in a direction to approach and separate from the semiconductor wafer W, and can be brought into contact with the outer peripheral chamfered surfaces S and M of the semiconductor wafer W with a predetermined pressing force. .

The outer peripheral polishing drum 50 has a wheel body 50a made of an aluminum alloy or the like which is fixed to a mounting flange 68 provided at the end of the drum support shaft 62 so as to have the same axis as the wheel body 50a. A strip-shaped chamfered polishing cloth 69 wound and fixed over the outer peripheral surface is provided. The chamfered polishing cloth 69 is made of a rubber belt containing SiO2 or a non-woven fabric having a non-uniform fiber orientation. A polishing liquid such as water is supplied from a polishing liquid supply means (not shown). Perform polishing.

As shown in FIGS. 1, 3, 8, and 9, the wafer rotating mechanism 70 is a suction device connected so as to extend vertically downward from the lower center of the suction plate 22 in a holding state. The disk support shaft 71, the suction disk support cylindrical portion 72 in which the suction disk support shaft 71 is inserted and rotatably supported by bearings 72a and 72b, and the suction disk support cylindrical portion 72 continuously. It has a cylindrical suction-disc support arm 73 formed so as to extend in the horizontal direction, and a suction-disc rotation motor 74 installed at the other end of the suction-disc support arm 73.

The lower end of the suction disk support shaft 71 reaches the inside of the cylindrical shape of the suction disk support arm 73, and the suction disk pulley 75 is fixed so as to be coaxial with the suction disk 22. Also, a motor-side pulley 76 fixed to the lower end of the suction-disc rotating motor 74 is disposed inside the cylindrical shape of the suction-disc supporting arm 73, and the suction-disc-side pool 75 and the motor-side pulley 76 It is connected by an endless belt 77 inside the cylindrical shape of the board support arm 73. The semiconductor wafer W held by the suction disk 22 is rotated by driving the suction disk rotation motor 74.

The suction disk rotating motor 74 is, for example, a servomotor, and can rotate the semiconductor wafer W held by the suction disk 22 by an arbitrary angle.

The wafer tilting mechanism 80 is fixedly connected so as to extend in the horizontal direction from one end of the suction disk supporting arm 73 and has a tilting arm 81 having a tilting shaft 84 at the base end.
A tilt support member 85 holding a base end side of the tilt arm 81 in a U-shape in plan view, a suction motor tilt motor 82 installed on the tilt support member 85, and the suction disk tilt motor 82
And a speed reducer 83 connected to the Tilt shaft 84
One of them is held by a speed reducer 83 connected to a suction disc tilting motor 82, and the other is rotatably supported by a bearing 86.

By driving the suction disk tilting motor 82, the tilting arm 81 is turned, and accordingly, the semiconductor wafer W held by the suction disk 22 connected to the suction disk supporting arm 73 is also turned. It has become so. At this time, the tilt shaft portion 84 extends on the extension of the semiconductor wafer W.
The outer peripheral polishing drum 50 is provided so as to have a contact portion with the outer peripheral polishing drum 50. In other words, the semiconductor wafer W held by the suction disk 22 is moved in parallel with the rotation axis of the notch polishing wheel 23 and the outer peripheral polishing drum 50 and the semiconductor wafer W.
The semiconductor wafer W is to be tilted with the vicinity of the portion where the contact is made as the tilt axis G.

At this time, the suction disc tilting motor 82 and the suction disc rotating motor 74 are driven independently of each other, and the suction disc 22 holding the semiconductor wafer W can be tilted while rotating. It has become.

The chamfered-surface polishing apparatus 4 configured as described above
A method for polishing the chamfered surface of the semiconductor wafer W using the method will be described.

First, as shown in FIG. 10, the unloading cassette C1 in which the semiconductor wafer W before the polishing process is placed is inserted into the unloading cassette C1.
The base 6 so that the surface of the semiconductor wafer W faces downward.
Set in the upper predetermined position.

Next, the loader unit 8 is driven to extend the picking hand 7 up and down toward the picking cassette C1 while moving the picking hand 7 up and down to move it above a predetermined semiconductor wafer W, thereby holding the semiconductor wafer W by suction. . After the suction, the semiconductor wafer W is taken out of the take-out cassette C1, and the take-out hand 7 is moved to transfer the semiconductor wafer W to the mounting table 9 of the wafer positioning unit 2.

The semiconductor wafer W is taken out of the hand 7
Is released on the mounting table 9 by releasing the suction. Then, the wafer positioning unit 2 is driven to center the semiconductor wafer W on the mounting table 9 and determine the direction of the notch portion V, thereby positioning the semiconductor wafer W in a predetermined direction.

When the positioning and orientation of the semiconductor wafer W is completed, the semiconductor wafer W is sucked and lifted by the suction groove 12a of the hand unit 12, and the hand unit 12 is horizontally moved in this state to polish the chamfered surface. It is transferred to the transfer unit 10 above the device 4.

Next, the shutter 1 of the chamfering surface polishing device 4
7 is slid by the operation of the shutter air cylinder 19 to open the top plate 16. Then, when the top plate 16 is opened, the semiconductor wafer W is lowered, and is placed and held on the suction plate 22. At this time, suction cup 2
The semiconductor wafer W held at 2 is arranged such that the notch portion V faces the notch polishing wheel 23.

After the semiconductor wafer W is held on the suction disk 22, the shutter air cylinder 19 is driven to slide the shutter 17, and the opening of the top plate 16 is closed.

Next, the polishing liquid supply means 26 is operated to
The polishing liquid is supplied from the polishing liquid supply nozzle 26a to the notch polishing cloth 3
9 is supplied. Then, while driving the rotation motor 33 to rotate the notch polishing wheel 23, the notch pressing cylinder 30 is driven to move the notch polishing wheel rotation drive unit 24 to the semiconductor wafer W side,
The notch polishing cloth 39 of the notch polishing wheel 23 is brought into contact with the notch portion V with a predetermined pressing force. At this time, the suction disk rotating motor 74 is stopped, and the semiconductor wafer W is not rotating.

At the same time, the suction disk 22 holding the semiconductor wafer W is slowly tilted by the wafer tilting mechanism 80. In other words, the suction disc tilting motor 82 of the wafer tilting mechanism 80 is driven, and the suction disc 2 is moved together with the suction disc supporting arm 73 around the tilt shaft 84 as the center of rotation.
Turn 2 In other words, since the semiconductor wafer W has a tilt axis G near the rotation axis of the notch polishing wheel 23 and near the part where the outer peripheral polishing drum 50 and the outer peripheral portion of the semiconductor wafer W are in contact with each other, FIG. As shown in (1), the contact portion with the notch polishing cloth 39 is largely swung. Then, reciprocating motion is performed within a predetermined range, and the entire inner surface of the notch portion V is polished.

At this time, the notch polishing wheel 23 provided with the notch polishing cloth 39 is
Is driven to reciprocate so as to approach and separate in the direction of the semiconductor wafer W in synchronization with the tilt of the semiconductor wafer W. That is, when the semiconductor wafer W is in the horizontal state, the notch polishing wheel 23 is moved to a position farthest from the semiconductor wafer W while applying a predetermined pressing force to the notch V. When the semiconductor wafer W is tilted up and down in FIG. 11, the pressing force of the notch polishing cloth 39 is always applied to the inner surface of the notch V so that the pressing force of the notch polishing cloth 39 is evenly applied to the semiconductor wafer W. It is getting closer.

At this time, as shown in FIG.
When the notch V side of the semiconductor wafer W is tilted upward in FIG. 12, the notch polishing wheel 23 rotates counterclockwise (arrow Y1) as shown in FIG. 12B, the notch V is polished while rotating clockwise (arrow Y2) as shown in FIG. 12B. In other words, the semiconductor wafer tilting mechanism 80 allows the semiconductor wafer W to move the contact portion between the inner surface of the notch V and the notch polishing cloth 39 between the tilt axis G of the semiconductor wafer W and the rotation axis of the notch polishing wheel 23. When tilted away from the reference line L tied orthogonally,
The notch polishing wheel rotation drive unit 24 rotates the notch polishing wheel 23 forward and backward so that the surface of the notch polishing cloth 39 at the contact portion faces the reference line L. In other words, the polishing is performed by rotating the notch polishing cloth 39 toward the reference line L, that is, toward the upper cut side (biting side), with the surface existing at the contact portion facing the reference line L.

Thus, while the semiconductor wafer W is tilted by the semiconductor wafer tilting mechanism 80 so as to reciprocate in a predetermined arc range, the notch polishing wheel 23 is moved toward and away from the semiconductor wafer W in synchronization with the tilt. Reciprocating to make the pressing force between the notch polishing wheel 23 and the inner surface of the notch portion V always contact vertically and uniformly, and the rotation direction of the notch polishing wheel 23 to the upper cut side. The notch portion V is polished by rotating it forward and backward so as to be as follows.

When the polishing of the notch portion V is completed, the drive of the rotation motor 33 of the notch polishing wheel 23 and the polishing liquid supply means 26 is stopped, and the notch pressing cylinder 30 is driven, so that the notch polishing wheel 23 From the notch V of the semiconductor wafer W.

Next, in order to polish the outer peripheral chamfered surfaces S and M of the semiconductor wafer W, the swinging air cylinder 67 of the polishing drum advance / retreat mechanism 51c is driven to bring the outer peripheral polishing drum 50 close to the semiconductor wafer W. At the same time, while driving the outer peripheral polishing drum 50 by driving the drum rotation motor 61, the outer peripheral polishing drum 50 and the semiconductor wafer W
Abut on the chamfered surface to be polished out of the outer peripheral portion. At this time, the polishing liquid is supplied from the polishing liquid supply means to the vicinity of the contact surface between the outer peripheral polishing drum 50 and the outer peripheral portion of the semiconductor wafer W.

Then, as shown in FIG. 13, the semiconductor wafer W held by the suction disk 22 is driven by driving the suction disk tilting motor 82 so that the vicinity of the contact portion between the outer peripheral polishing drum 50 and the semiconductor wafer W is reduced. The tilt is made to be the tilt axis G. That is, as shown in FIG. 14, for example, when polishing the front side chamfer M, the semiconductor wafer W is moved to the position K1.
When it is desired to grind the back side chamfered surface M as described above, the semiconductor wafer W is tilted to the position K2 for polishing. When the tip side chamfer S is to be polished, the semiconductor wafer W is kept horizontal, and the tip side chamfer S is brought into contact with the polishing pad 69 provided on the outer peripheral polishing drum 50 to perform polishing.

At this time, the outer peripheral polishing drum 50 is guided by the guide 55 by the linear motion portion 58 of the polishing drum linear motion mechanism 51b.
Along the axis of rotation of the outer peripheral polishing drum 50. By reciprocating the outer peripheral polishing drum 50 in the rotation axis direction, the chamfered surfaces S and M are slid while being polished by the outer peripheral polishing drum 50.

Thus, for example, when it is desired to polish the surface chamfered surface M, the outer peripheral polishing drum 50 is rotated while being reciprocated in the direction of the rotation axis thereof, and the surface chamfered surface M and the polishing cloth 69 are maintained for a predetermined time. The semiconductor wafer W held by the suction disk 22 is rotated by driving the suction disk rotation motor 74 while inclining the semiconductor wafer W by a predetermined angle for a predetermined time so as to make contact with the semiconductor wafer W.

When the polishing of the front side chamfer M is completed, the semiconductor wafer tilting mechanism 80 is driven to polish the rear side chamfer M, for example, and the semiconductor wafer W is polished.
Is tilted at a predetermined angle, and polishing is performed in the same manner. In this way, the plurality of outer peripheral chamfered surfaces S and M are continuously polished.

When the polishing of the chamfered surfaces S and M of the notch portion V and the outer peripheral portion is completed, the semiconductor wafer W is sent to a semiconductor wafer W cleaning step (not shown).

As described above, the semiconductor wafer W held by the suction disk 22 is parallel to the rotation axis of the notch polishing wheel 23 provided with the notch polishing cloth 39, and is formed between the outer peripheral polishing drum 50 and the semiconductor wafer W. The vicinity of the portion where the outer peripheral portion is in contact is tilted about the tilt axis G, and the notch portion V is rotated by the notch polishing wheel 23 rotated by the notch polishing wheel rotation drive unit 24 by the notch polishing cloth 39 provided on the notch polishing wheel 23. Polished. Since the notch portion V is polished by the notch polishing cloth 39 while tilting, the inner surface is entirely polished.

At this time, the contact portion of the semiconductor wafer W between the inner surface of the notch portion V and the polishing cloth 39 for notch is set so that the tilt axis G of the semiconductor wafer W and the rotation axis of the polishing cloth 39 for notch are perpendicular to each other. When the notch polishing cloth 39 is tilted away from the connected reference line L, the notch polishing cloth 39 is rotated forward and backward so that the surface at the contact portion faces the reference line L. That is, the notch polishing cloth 39 is rotated to the biting side (upper cut side).

Therefore, burrs B tend not to be generated at the end of the notch polishing cloth 39, and polishing unevenness caused by the burrs B can be eliminated. Further, even if burrs B are generated, the notch polishing cloth 39 is rotated to the upper cut side, so the generated burrs B are cut naturally, so that the burrs B are not easily generated on the notch polishing cloth 39. I have.

The tilt axis G of the semiconductor wafer W at this time is parallel to the rotation axis of the notch polishing wheel 23 and near the portion where the outer peripheral polishing drum 50 and the outer peripheral portion of the semiconductor wafer W abut. Is provided. That is, it is set far from the contact portion between the notch portion V and the polishing cloth 39 for notch. Therefore, even if the notch polishing cloth 39 is rotated to the upper cut side, the action of vibrations and moments that adversely affect the semiconductor wafer W, such as chatter vibration, is reduced.
The semiconductor wafer W is polished stably.

Further, an outer peripheral polishing drum 50 for polishing the outer peripheral portion of the semiconductor wafer W is disposed at a position facing the notch polishing wheel 23 with respect to the semiconductor wafer W, and the semiconductor wafer W And the outer peripheral polishing drum 50 and the outer peripheral chamfered surfaces S and M of the semiconductor wafer W are brought into contact with each other for polishing. When polishing S and M, the semiconductor wafer W need only be tilted by the semiconductor wafer tilting mechanism 80.

In other words, even when the chamfered surfaces S and M on the front and back sides or the tip side of the outer peripheral portion of the semiconductor wafer W are polished, the step of inverting the entire semiconductor wafer W is not required, and the chamfered surfaces S and M are not required. Polishing can be performed continuously at once. Therefore, the number of polishing steps and time can be reduced, and the contact angle between the outer peripheral polishing drum 50 and the outer peripheral chamfered surfaces S and M can be set arbitrarily. It is possible to flexibly cope with polishing.

Further, since it is no longer necessary to invert the semiconductor wafer W, the semiconductor wafer W may be supported only on one side by the suction disk 22 in the polishing step, and the occurrence of scratches on the surface is minimized. Can be suppressed. That is, when the semiconductor wafer W needs to be inverted, the semiconductor wafer W is
It is necessary to support the front and back surfaces respectively, but by providing the semiconductor wafer tilting mechanism 80, the outer peripheral chamfered surfaces S and M can be polished only by single-sided support.

Since the notch polishing wheel 23 and the outer peripheral polishing drum 50 are disposed so as to face each other with the semiconductor wafer W as a reference, the notch portion V and the outer peripheral portion chamfered surfaces S and M can be polished. The transfer mechanism and the like are omitted, and the size of the apparatus can be reduced and the number of steps can be reduced. In addition, since the chamfered surfaces S and M of the outer peripheral portion of the semiconductor wafer W are polished by the same mechanism, the operations are continuously performed, the efficiency is improved, and the space of the entire apparatus is reduced. Can be realized, and cost reduction and stable polishing of each chamfered surface can be performed.

The notch polishing wheel 23 can be moved in the direction of contact with the notch portion V of the tilted semiconductor wafer W by the notch polishing wheel swing drive unit 25. Polishing cloth 39
Can be arbitrarily set while constantly applying the pressing force in the perpendicular direction. Therefore, a uniform pressing force can be applied to the inner surface of the notch portion V, and stable polishing without unevenness can be performed.

The outer peripheral polishing drum 50 is configured to polish the outer peripheral chamfered surfaces S and M while reciprocating in the direction of the rotation axis thereof by the polishing drum linear motion mechanism 51b. Therefore, the abrasion of the surface of the outer peripheral polishing drum 50 is not uneven, and accordingly, the polished surfaces of the outer peripheral chamfered surfaces S and M are uniform and excellent. Further, the pressing force against the outer peripheral chamfered surfaces S and M can be set arbitrarily.

As shown in FIG. 15A, the thickness of the notch polishing cloth 39 was smaller than the circumferential width of the notch V, and the notch polishing cloth 39 was brought into contact with the inner surface of the notch V. The suction disk rotating motor 7 composed of a servomotor
The notch V can be polished by swinging the notch 4 in the circumferential direction. Since the thickness of the notch polishing cloth 39 is smaller than the circumferential width of the notch portion V, the notch polishing cloth 39 is formed.
Does not interfere with the notch portion V, and the occurrence of burrs B of the notch polishing cloth 39 is reduced. Then, by rotating the semiconductor wafer W in the circumferential direction while the notch polishing cloth 39 is kept in contact with the notch portion V, the inside of the notch portion V is entirely and stably polished.

Alternatively, as shown in FIG. 15B, the thickness of the notch polishing cloth 39 is smaller than the circumferential width of the notch V, and the notch polishing cloth 39 is kept in contact with the inner surface of the notch V. It is also possible to provide a notch polishing wheel swinging mechanism for reciprocating in the direction of the rotation axis of the notch. With such a configuration, the end of the notch polishing cloth 39 does not interfere with the notch V, and the occurrence of burrs B can be reduced, and as a result, polishing unevenness can be reduced.

[0096]

The apparatus and method for chamfering a semiconductor wafer according to the present invention have the following effects.

According to the first aspect of the present invention, the semiconductor wafer held by the wafer suction disk is parallel to the rotation axis of the notch polishing wheel, and the outer peripheral polishing drum and the outer peripheral portion of the semiconductor wafer. The notch portion is polished by a notch polishing cloth provided on a notch polishing wheel rotated by the notch polishing wheel rotating mechanism.
The notch portion V is polished to the notch polishing cloth while tilting, so that the inner surface is entirely polished. Further, an outer peripheral polishing drum for polishing an outer peripheral portion of the semiconductor wafer is disposed at a position facing the notch polishing wheel with respect to the semiconductor wafer, and the semiconductor wafer is tilted about the tilt axis. In addition, because the outer peripheral polishing drum and the outer peripheral chamfered surface of the semiconductor wafer are brought into contact with each other for polishing, when polishing each chamfered surface on the front and back surfaces and the tip side of the outer peripheral portion,
It is only necessary to tilt the semiconductor wafer by the tilt mechanism. That is, even when polishing each chamfered surface on the front and back sides or the front end side of the outer peripheral portion of the semiconductor wafer, the step of inverting the entire semiconductor wafer is not required, and the polishing of each chamfered surface can be continuously performed at once. . for that reason,
The number and time of the polishing process can be reduced, and the contact angle between the outer peripheral polishing drum and the chamfer surface of the outer peripheral portion of the semiconductor wafer can be set arbitrarily, so that it can flexibly cope with polishing of semiconductor wafers of various specifications. be able to. Further, since it is no longer necessary to invert the semiconductor wafer, the support of the semiconductor wafer at the time of polishing may be performed on either one of the front and back surfaces, for example, holding by a chuck or the like can be minimized, The occurrence of scratches and the like due to holding can be reduced. Furthermore, since the notch polishing wheel and the outer peripheral polishing drum are disposed so as to face each other with the semiconductor wafer as a reference, the transport mechanism and the like between the notch portion polishing step and the respective chamfering surface polishing steps of the outer peripheral part are omitted, and the apparatus is not used. It is possible to reduce the size and the number of steps. In addition, since the polishing of each chamfered surface of the semiconductor wafer outer peripheral portion is performed by the same mechanism, work efficiency can be improved, and space saving of the entire apparatus can be realized, cost reduction, and reduction of each chamfered surface. Stable polishing can be performed.

According to the second aspect of the present invention, since the notch polishing wheel can be moved in the direction of separation from the notch portion of the tilted semiconductor wafer, the notch with respect to the inner surface of the notch portion is formed. The pressing force of the polishing pad for polishing can be arbitrarily set while constantly acting. Therefore, a uniform pressing force can be applied to the inner surface of the notch portion, and stable polishing without unevenness can be performed. Further, during the outer peripheral chamfering polishing step, the semiconductor wafer is retracted from the vicinity of the semiconductor wafer.

According to the third aspect of the present invention, the semiconductor wafer has a contact portion between the inner surface of the notch and the polishing cloth for the notch, and the tilt axis of the semiconductor wafer and the polishing cloth for the notch. When the notch polishing cloth is tilted away from a reference line tied at right angles to the rotation axis, the notch polishing cloth is rotated forward and backward so as to direct the surface at the contact portion to the reference line. It has become. That is,
The polishing cloth for the notch is rotated to the biting side (upper cut side). Therefore, no burrs are generated at the end of the notch polishing cloth, and uneven polishing can be eliminated. Even if burrs are formed, since the notch polishing cloth is rotated toward the upper cut side, the generated burrs are cut naturally, so that the notch polishing cloth is less likely to generate burrs. The tilt axis of the semiconductor wafer at this time is parallel to the rotation axis of the notch polishing wheel, and is provided near a portion where the outer peripheral polishing drum and the outer peripheral portion of the semiconductor wafer are in contact with each other, that is, It is set far from a contact portion between the notch portion and the polishing cloth for the notch. Therefore, even when the notch polishing cloth is rotated to the upper cut side, the action of vibrations and moments that adversely affect the semiconductor wafer W, such as chatter vibration, is reduced. Is polished stably.

According to the fourth aspect of the present invention, the outer peripheral polishing drum grinds the outer peripheral chamfer while reciprocating in the direction of the rotation axis. Therefore, the wear of the surface of the outer peripheral polishing drum is not uneven, and the polished surface of the outer peripheral chamfered surface is uniform and favorable. The outer peripheral polishing drum is movable in the direction of coming and going from the semiconductor wafer, and is retracted during the notch portion polishing step. Further, the pressing force against the outer peripheral chamfered surface can be arbitrarily set.

According to the fifth aspect of the present invention, the thickness of the notch polishing cloth is set to be smaller than the circumferential width of the notch, so that the end of the notch polishing cloth does not interfere with the notch. Burrs of the notch polishing cloth are reduced. Then, by rotating the semiconductor wafer in the circumferential direction while the notch polishing cloth is kept in contact with the notch portion, the inside of the notch portion is polished stably as a whole.

According to the sixth aspect of the present invention, by providing the thickness of the notch polishing cloth smaller than the circumferential width of the notch portion, the edge of the notch polishing cloth and the notch portion can interfere with each other. And the occurrence of burrs can be reduced, and as a result, polishing unevenness can be reduced.
By supporting the polishing cloth for the notch so as to be reciprocally movable in the direction of the rotation axis, the inner surface of the notch is entirely uniformly polished.

According to the seventh aspect of the present invention, the polishing of the inner surface of the notch portion can be performed while suppressing burrs of the polishing cloth for the notch and reducing the adverse effects such as vibration and moment on the semiconductor wafer. It is performed uniformly. And since the outer peripheral polishing drum is arranged at the position facing the notch polishing cloth, the semiconductor wafer is held by one wafer suction disk, and the polishing of the inner surface of the notch portion and the polishing of the outer peripheral chamfer surface are continuously performed. It can be carried out. Further, since the semiconductor wafer is tilted, the respective chamfered surfaces on the front and back sides of the outer peripheral portion can be continuously polished, so that space-saving and efficient polishing can be performed.

[Brief description of the drawings]

FIG. 1 is a plan view seen from above showing an example of an embodiment of a chamfered surface polishing apparatus for a semiconductor wafer of the present invention.

FIG. 2 is a front view of FIG. 1 as viewed from the front.

FIG. 3 is a plan view seen from above showing an example of an embodiment of a chamfered surface polishing apparatus for a semiconductor wafer of the present invention.

FIG. 4 is a plan view illustrating the outer peripheral polishing drum and the outer peripheral polishing drum driving unit as viewed from above.

FIG. 5 is a front view of FIG. 4 as viewed from an outer peripheral polishing drum driving unit.

FIG. 6 is a sectional view of FIG. 4 as viewed from the side.

FIG. 7 is a view for explaining a linear motion mechanism of the outer peripheral polishing drum driving means.

FIG. 8 is a diagram illustrating a wafer suction disk holding a semiconductor wafer and a wafer rotating mechanism.

FIG. 9 is a plan view of FIG. 8 as viewed from the front.

FIG. 10 is a diagram illustrating an entire system including a chamfering surface polishing apparatus for a semiconductor wafer according to the present invention.

FIG. 11 is a diagram illustrating a relationship between a semiconductor wafer and a notch polishing wheel.

FIG. 12 is a diagram illustrating a rotation direction of a notch polishing wheel.

FIG. 13 is a diagram illustrating a relationship between a semiconductor wafer and an outer peripheral polishing drum.

FIG. 14 is a diagram illustrating a portion of FIG. 13 where an outer peripheral polishing drum and an outer peripheral portion of a semiconductor wafer W are in contact with each other.

FIG. 15 is a diagram illustrating another embodiment when polishing a notch portion.

FIG. 16 is a view illustrating a conventional chamfering surface polishing apparatus.

FIG. 17 is a diagram illustrating a notch portion.

FIG. 18 is a diagram illustrating a grindstone for forming a notch portion.

19 is a sectional view taken along line AA of FIG.

FIG. 20 is a diagram illustrating a conventional chamfering surface polishing apparatus.

FIG. 21 is a diagram illustrating a conventional chamfering surface polishing apparatus.

FIG. 22 is a view illustrating a conventional chamfering surface polishing apparatus.

FIG. 23 is a view for explaining how burrs are generated on the notch polishing cloth.

FIG. 24 is a view illustrating a conventional chamfering surface polishing apparatus.

FIG. 25 is a diagram illustrating a conventional chamfering surface polishing apparatus.

[Explanation of symbols]

4 Chamfering Surface Polishing Device 22 Suction Board 23 Notch Polishing Wheel 24 Notch Polishing Wheel Rotary Drive (Notch Polishing Wheel Rotary Mechanism) 25 Notch Polishing Wheel Swinging Drive 30 Notch Press Cylinder 33 (Notch Polishing Wheel) Rotating motor 39 Notch polishing cloth 50 Peripheral polishing drum 51 Peripheral polishing drum driving means 51a Polishing drum rotation mechanism 51b Polishing drum linear movement mechanism 51c Polishing drum advance / retreat mechanism 58 Linear part 61 Drum rotation motor 67 Oscillating air cylinder 69 (Peripheral polishing drum) Polishing cloth 70 Wafer rotating mechanism 74 Suction disk rotating motor 80 Semiconductor wafer tilting mechanism 82 Suction disk tilting motor W Semiconductor wafer V Notch S Outer peripheral chamfering surface W Outer peripheral chamfering surface B

Claims (7)

[Claims] 1. An apparatus for polishing a chamfered surface of a semiconductor wafer for polishing a chamfered surface of a notch portion and an outer peripheral portion of the semiconductor wafer, comprising: a wafer suction disk holding the semiconductor wafer; and a wafer suction disk held by the wafer suction disk. A semiconductor wafer rotating mechanism for rotating a semiconductor wafer, a notch polishing wheel provided with a disk-shaped or annular notch polishing cloth having a cross-sectional shape of a peripheral portion substantially similar to a notch portion shape, and a peripheral edge of the notch polishing cloth. A notch polishing wheel rotating mechanism for rotatably supporting the notch polishing wheel while pressing a portion against the inner surface of the notch portion, and a cylinder disposed at a position facing the notch polishing cloth with respect to the semiconductor wafer. -Shaped outer peripheral polishing drum, and contacting the outer peripheral polishing drum with the outer peripheral chamfered surface of the semiconductor wafer. An outer peripheral polishing drum rotating mechanism rotatably supporting, a semiconductor wafer held by the wafer suction disk, parallel to a rotation axis of the notch polishing wheel, and an outer peripheral portion of the outer peripheral polishing drum and the semiconductor wafer; A semiconductor wafer tilting mechanism for tilting around a portion in contact with the semiconductor wafer as an axis. 2. The apparatus for polishing a chamfered surface of a semiconductor wafer according to claim 1, wherein the notch polishing wheel is provided with the notch with respect to an inner surface of a notch portion of the semiconductor wafer tilted by the semiconductor wafer tilting mechanism. A notch polishing wheel advancing / retreating mechanism for moving the semiconductor wafer in the direction of contact and detachment so that the pressing force of the polishing cloth is always kept constant. . 3. The apparatus for polishing a chamfered surface of a semiconductor wafer according to claim 1, wherein the semiconductor wafer is brought into contact with the inner surface of the notch and the polishing cloth for the notch by the semiconductor wafer tilting mechanism. When the portion is tilted away from a reference line that connects the tilt axis of the semiconductor wafer and the rotation axis of the notch polishing wheel at right angles, the notch polishing wheel rotation mechanism rotates forward and reverse. A chamfering surface polishing apparatus for a semiconductor wafer, wherein the notch polishing wheel is rotated in one direction such that the surface of the notch polishing cloth at the contact portion is directed to the reference line. 4. The polishing apparatus for chamfering a semiconductor wafer according to claim 1, wherein said outer peripheral polishing drum is linearly moved to reciprocate the polishing drum in a rotation axis direction. An apparatus for polishing a chamfered surface of a semiconductor wafer, comprising: a mechanism; and a polishing drum advancing / retreating mechanism for moving the semiconductor drum in a direction of contact and separation from the semiconductor wafer. 5. The polishing apparatus for chamfering a semiconductor wafer according to claim 1, wherein the polishing cloth for the notch is provided with a thickness smaller than a circumferential width of the notch. The wafer rotation mechanism is characterized in that the wafer suction disk is provided with a servomotor that swings in the circumferential direction while the notch polishing cloth is in contact with the inner surface of the notch, wherein the servomotor is provided. Chamfer polishing machine. 6. The apparatus for polishing a chamfered surface of a semiconductor wafer according to claim 1, wherein a thickness of the polishing cloth for the notch is smaller than a width of the notch portion in a circumferential direction. A polishing wheel for rocking the notch, wherein the polishing wheel for rocking the notch is reciprocated in a rotation axis direction while the polishing cloth for the notch is kept in contact with the inner surface of the notch. Surface polishing equipment. 7. A method for polishing a chamfered surface of a semiconductor wafer for polishing a chamfered surface of a notch portion and an outer peripheral portion of the semiconductor wafer, the method comprising: rotating the semiconductor wafer held by a rotatable wafer suction disk in forward and reverse directions. A notch polishing wheel provided with a disc-shaped or annular notch polishing cloth having a shape of a peripheral portion substantially supported by the notch portion and a cylindrical outer peripheral polishing drum rotatably supported. The semiconductor wafer held by the wafer suction disk is arranged parallel to the rotation axis of the polishing wheel for the notch, and the outer peripheral polishing drum and the outer peripheral portion of the semiconductor wafer. While the tip is tilted about the vicinity of the contacted portion as an axis, the contact portion between the inner surface of the notch and the polishing cloth for the notch is moved to the tilting axis of the semiconductor wafer and the polishing notch for the notch. When tilted away from the reference line tied perpendicular to the rotation axis of the eel respectively, the notch polishing wheel,
An axis in a direction perpendicular to the axis of the semiconductor wafer while pressing the peripheral edge of the notch polishing cloth against the inner surface of the notch so that the surface of the polishing cloth for notch in the contact portion faces the reference line. While rotating forward and reverse to the center, the pressing force of the polishing cloth for the notch against the inner surface of the notch is applied in a vertical direction, and the entire inner surface of the notch is polished by moving the semiconductor wafer toward and away from the semiconductor wafer. Next, the semiconductor wafer is tilted at a predetermined angle while rotating, and the outer peripheral polishing drum is reciprocated in the rotation axis direction while being rotated about an axis perpendicular to the rotation axis of the notch polishing wheel. The outer peripheral chamfered surface is polished by being brought into contact with one chamfered surface of the outer peripheral portion of the semiconductor wafer while changing the tilt angle of the semiconductor wafer. It allows chamfer polishing method of a semiconductor wafer, comprising polishing a plurality of chamfered surfaces of the outer peripheral portion continuous to.