JP2003007657A - Mirror-surface polisher for wafer notch, and mirror- surface polishing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve contact of a polishing disc with a wafer notch for improving efficiency of the mirror-surface polishing for the wafer notch; and to solve the problem of the offset of the disc from the notch, increasing with the diametrical increase of a semiconductor wafer to deteriorate the contact of the disc, result in an inefficient mirror surface polishing of the notch. SOLUTION: A wafer shuck table 31 is tiltable at an angle position for polishing the notch end faces and a notch bevel face. In polishing, a main shaft base unit 2 is energized for pushing a polishing disc dkc or dkb into the notch at adequate polishing pressure. In parallel thereto, the base unit 2 is moved reciprocatively in the notch, to improve the contact of the disc with the notch.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus therefor for mirror-polishing a notch formed in a semiconductor wafer, and in particular, the initial alignment between the polishing disk and the notch in the mirror-polishing apparatus is insufficient. Even in such a case, it is an object to provide a polishing method or a mirror polishing apparatus capable of mirror polishing the entire surface of the notch evenly.

[0002]

2. Description of the Related Art A semiconductor device is manufactured by sequentially carrying a semiconductor wafer between a number of stations in a semiconductor manufacturing system and performing necessary processing at each station.

At each station, in many cases, the semiconductor wafer must be fixed so as to take a predetermined position and direction in each apparatus in each processing. For this reason, conventionally, a linear notch called an orientation flat is formed on a semiconductor wafer, and positioning and orientation are performed based on this line.
In recent years, since the orientation flat reduces the effective usable area of an expensive semiconductor wafer, a small V-shaped notch has been added to reduce the area.

FIG. 1 shows the appearance of a semiconductor wafer having this notch, in which (a) is its plan view and (b) is its plan view.
Is a partial cross-sectional view thereof. FIG. 2 is an enlarged perspective view showing the vicinity of the notch. W is a semiconductor wafer, Sp is a pattern formation surface, and N is the notch. The semiconductor wafer W is apt to be chipped due to the nature of the material. Therefore, in order to prevent chipping from occurring in the manufacturing process or for other reasons, the entire periphery of the semiconductor wafer is obliquely dropped by grinding to form the bevel surface Sb. The as-ground surface causes dust generation for a reason not described here and reduces the yield in semiconductor manufacturing.
Along with it, it is polished to a mirror surface. This mirror polishing is also performed on the bevel surface of the notch N (notch bevel surface Sbn) and the surface parallel to the central axis Wc of the wafer (notch end surface Scn).

FIG. 3 is an explanatory view showing an outline of the mirror polishing apparatus PM and its periphery in the semiconductor manufacturing system.
The semiconductor wafer W is transferred from the upstream (left side in FIG. 3) and placed on the positioning unit OU. In the positioning unit OU, the position and direction of the placed semiconductor wafer W are adjusted in advance so that the semiconductor wafer W is loaded on the mirror polishing apparatus PM at a predetermined position and a predetermined direction. The semiconductor wafer W whose position and direction have been adjusted is loaded into the mirror polishing apparatus PM by the transfer robot TR. The semiconductor wafer W that has been mirror-polished by the mirror-polishing apparatus PM is transported again to the next step by the transport robot TR.

Examples of the semiconductor wafer mirror polishing apparatus as described above are disclosed in Japanese Patent Nos. 2798345 and 27983.
47 or Japanese Patent Laid-Open No. 2000-317790, a disk-shaped or annular polishing disk is brought into contact with a notch of a semiconductor wafer W, and the semiconductor wafer W is rotated around its central axis in a pulsating or circumferential direction. The notch part is ground by rocking. However, the positioning unit OU
The position and direction adjusted in (1) are not sufficiently accurate, and since the position and direction are transferred via the transfer robot TR, an error in transfer is also added to the position, so that the mirror polishing apparatus PM was loaded. At times, it was unavoidable that the semiconductor wafer W deviated from a predetermined position and direction.

In recent years, the semiconductor wafer W has been changed to a wafer having a larger diameter from the viewpoint of improving productivity. The deviation of the position and the direction causes a large deviation between the polishing disk and the notch, and the larger the diameter, the more the contact of the polishing disk with a part of the notch becomes very bad. Has come to be required.

[0008]

SUMMARY OF THE INVENTION In view of the above problems, it is an object of the present invention to improve the efficiency of mirror polishing of a wafer notch by improving the contact of the polishing disk with the wafer notch.

[0009]

The above problems can be solved by the following means. That is, a solution means of the first invention is a headstock, a shaft for mounting a polishing disk, a tool spindle rotatably supported by the headstock, and a tool spindle for rotationally driving the tool spindle. A spindle drive source; vertical guide means for guiding the headstock in the axial direction of the spindle shaft; lateral guide means for guiding the headstock in a direction perpendicular to the spindle shaft; Vertical drive means for driving the headstock in the direction guided by the vertical guide means, horizontal drive means for driving the headstock in the direction guided by the lateral guide means, and wafer support A wafer chuck table that is tiltable around an axis in a plane including the guide direction of the vertical guide means and the guide direction of the horizontal guide means, and the wafer chuck table. In a mirror polishing apparatus for a wafer notch, which comprises a table tilting means for tilting the ha-chuck table, the lateral driving means is supported by the notch of the wafer supported on the wafer chuck table and the tool spindle. The polishing disk has a biasing function of biasing the polishing disk against each other, and the longitudinal driving means supports the polishing disk supported by the tool spindle in the notch of the wafer supported on the wafer chuck table. Has an oscillation function for driving the tip of the device so as to perform a linear reciprocating motion within the notch.

A second means of solving the invention is a headstock,
A shaft for mounting a polishing disk, a tool spindle rotatably supported by the headstock, and a spindle drive source for rotationally driving the tool spindle,
Lateral guide means for guiding the headstock in a direction perpendicular to the spindle axis, lateral drive means for driving the headstock in the direction guided by the lateral guide means, and supporting the wafer. And a wafer chuck table tiltable about an in-plane axis including the axial direction of the spindle shaft and the guide direction of the lateral guide means, and the wafer chuck table and the spindle shaft. Longitudinal guide means for guiding in the axial direction of
A mirror polishing apparatus for a wafer notch, comprising: a vertical drive means for driving the wafer chuck table in a direction guided by the vertical guide means; and a table tilting means for tilting the wafer chuck table. The lateral drive means has a biasing function of biasing the notch of the wafer supported on the wafer chuck table and the polishing disk supported by the tool spindle so as to press each other. Means have an oscillation function for driving a tip of a polishing disk supported by the tool spindle in a notch of a wafer supported on the wafer chuck table so as to make a linear reciprocating motion in the notch. It is a thing.

A wafer notch mirror-polishing apparatus according to a third aspect of the present invention is the wafer notch mirror-polishing apparatus according to the first or second aspect of the present invention, wherein the wafer chuck table is faced to the polishing disk. The tilting angle for making the end face of the notch grindable and the other tilting angle for making the notch bevel surface grindable by directly facing the grinding disk make it possible to tilt at least two angles.

With the above structure, in the present invention, the wafer chuck table is tilted to face the notch end surface and the notch bevel surface, and the polishing disk relatively linearly reciprocates in the axial direction in this state. Even when the wafer chuck table is loaded with misalignment, the entire surface of the notch end surface and the notch bevel surface can be uniformly polished. Further, since there is no bias in polishing, it is not necessary to unnecessarily lengthen the polishing time.

According to a fourth aspect of the invention, there is provided a headstock,
A shaft for mounting a polishing disk, a tool spindle rotatably supported by the headstock, and a spindle drive source for rotationally driving the tool spindle,
Vertical guide means for guiding the headstock in the axial direction of the spindle shaft, horizontal guide means for guiding the headstock in a direction perpendicular to the spindle shaft, and the headstock in the longitudinal direction. A height direction guide means for guiding the headstock in directions perpendicular to the two directions in which the direction guide means and the lateral guide means respectively guide the headstock, and the vertical guide means guides the headstock. A vertical drive means for driving the headstock in a direction, a lateral drive means for driving the headstock in a direction guided by the lateral guide means, and a direction in which the headstock guides the headstock. In a mirror polishing apparatus for a wafer notch, which comprises a height direction driving means for driving the wafer notch and a wafer chuck table for supporting the wafer, the lateral direction driving means is the wafer chuck table. Has a biasing function of biasing the notch of the wafer supported on the wafer chuck and the polishing disk supported on the tool spindle so as to press each other, and the vertical driving means is supported on the wafer chuck table. In the notch of the wafer, the tip of the polishing disk supported by the tool spindle has an oscillation function for driving so as to perform linear reciprocating motion in the notch.

A wafer notch mirror-polishing apparatus according to a fifth aspect of the present invention is the wafer notch mirror-polishing apparatus according to the third aspect, wherein the headstock has the notch end surface and the notch bevel surface respectively as the polishing disk. It can be moved to a directly facing position by the lateral drive means and the height drive means.

With the above structure, in the present invention, the headstock is moved to cause the polishing disk to face the notch end surface and the notch bevel surface, and in this state, the polishing disk makes a linear reciprocating motion in the axial direction. Even when the wafer is shifted and loaded on the wafer chuck table, the entire surface can be uniformly polished. Further, since there is no bias in polishing, it is not necessary to unnecessarily lengthen the polishing time.

A sixth means of solving the invention is a headstock,
A shaft for mounting a polishing disk, a tool spindle rotatably supported by the headstock, and a spindle drive source for rotationally driving the tool spindle,
A wafer chuck table for supporting a wafer, a vertical guide means for guiding the headstock in the axial direction of the spindle shaft, and a lateral direction for guiding the headstock in a direction perpendicular to the spindle shaft. Direction guide means, and height direction guide means for guiding the wafer chuck table in directions perpendicular to the two directions in which the vertical guide means and the horizontal guide means guide the headstock, respectively. A vertical drive means for driving the headstock in a direction guided by the vertical guide means, a lateral drive means for driving the headstock in a direction guided by the lateral guide means, and the wafer In the mirror polishing apparatus for a wafer notch, which comprises a height direction driving means for driving the chuck table in a direction guided by the height direction guiding means, Has a biasing function of biasing the notch of the wafer supported on the wafer chuck table and the polishing disk supported by the tool spindle so as to press each other. In the notch of the wafer supported on the wafer chuck table, the tip of the polishing disk supported by the tool spindle is provided with an oscillation function for driving so as to make a linear reciprocating motion in the notch. .

The wafer notch mirror polishing apparatus of the seventh invention is the wafer notch mirror polishing apparatus of the fifth invention, wherein the wafer chuck table has the notch end surface and the notch bevel surface, respectively. It is moved to a position directly facing the position by the lateral direction driving means and the height direction driving means.

With the above-described structure, in the present invention, the wafer chuck table moves to cause the polishing disk to face the notch end surface and the notch bevel surface, and in this state the polishing disk makes a linear reciprocating motion in the axial direction. Even when the wafer is shifted and loaded on the wafer chuck table, the entire surface can be uniformly polished. Further, since there is no bias in polishing, it is not necessary to unnecessarily lengthen the polishing time.

An eighth aspect of the wafer notch mirror-polishing apparatus is the wafer notch mirror-polishing apparatus of the first through seventh aspects of the invention, for further supplying slurry to a polishing disk attached to the tool spindle. It is equipped with a slurry supply means. In the present invention, the slurry supplied to the polishing disk is eventually supplied to the polishing surfaces of the polishing disk and the wafer, and the notch of the wafer is polished.

A ninth means of solving the problem is a mirror-polishing method for mirror-polishing a rotating polishing disk while pressing it into a notch of a wafer, and between the polishing disk and the wafer. A mirror notch polishing method for a wafer notch in which a linear reciprocating motion is given in the notch along the direction of the rotation axis of the polishing disc, and slurry is supplied to the polishing disc.

With the above-described structure, in the present invention, the polishing disk makes a linear reciprocating motion in the axial direction of the notch end surface and the notch bevel surface, so that the wafer is shifted and loaded on the wafer chuck table. Even in this case, it is possible to uniformly polish the entire surface of both the notch end surface and the notch bevel surface. Further, since there is no bias in polishing, it is not necessary to unnecessarily lengthen the polishing time.

[0022]

DETAILED DESCRIPTION OF THE INVENTION

Example 1 FIGS. 4 and 5 are a front view and a plan view of Example 1 for explaining a mirror polishing apparatus of the present invention.

The mirror polishing apparatus of this embodiment comprises a base 1, a headstock unit 2, and a wafer chuck unit 3. The headstock unit 2 includes a headstock box 21 and the headstock box 2
1. A tool spindle 22 rotatably supported by 1 and a spindle motor 2 for rotationally driving the tool spindle 22.
3 is provided. A pulley 24 is fixed to the rotary shaft of the spindle motor 23, a pulley 26 is fixed to the tool spindle 22, and a transmission belt 25 is stretched over both pulleys. The rotational force of the spindle motor 23 is transmitted to the pulley 24, the transmission belt 25, and the pulley 26 attached to the tool spindle 22, and the tool spindle 2
2 rotates. The rotation of the tool spindle 22 causes the polishing disks dkc and dkb attached thereto to rotate. Incidentally, here, the polishing disk dkc is a notch end surface S.
For polishing cn, the polishing disk dkb is a disk for polishing the notch bevel surface Sbn.

On the base 1, there is a vertical feed unit 4 forming a guide feed mechanism in the axial direction of the tool spindle 22 (left-right direction in FIG. 4, hereinafter referred to as x-axis direction). A transverse feed unit 5 which is a guide feed mechanism in a direction orthogonal to this (in the front-back direction of the paper in FIG. 1, referred to as the y-axis direction) is provided on the surface 4. The headstock unit 2 is a y-table 20 which forms the transverse feed unit 5.
It is provided above.

The vertical feed unit 4 is fixed on the base 1 and slide guides 41 parallel to each other along the x-axis direction.
1, 412 and these slide guides 411, 412
It consists of a slider that slides up and is provided below the x-table 50.

A servomotor 43 is fixed to the base 1 and a female screw member 45 is fixed below the x table 50. A feed screw 44, which is rotationally driven by the servomotor 43, is screwed into the female screw member 45. ing.

The lateral feed unit 5 is fixed on the x-table 50, and slide guides 511 and 512 parallel to each other along the y-axis direction and these slide guides 511 and 5 are provided.
12 and a slider provided below the y-table 20.

The y-table 20 has two wires 531,
One end of 532 is fixed and pulleys 533, 534
After being hung on the other end, the other ends are weights 535 and 53.
It is fixed at 6. The weights 535 and 536 are suspended from the base 1 by the wires 531 and 532. The pulleys 533 and 534 are the x-table 5
It is rotatably supported by a support member fixed to zero.

The y-table 20 has weights 535 and 53.
A force in the y-axis direction corresponding to the weight of 6 is applied to the tool spindle 22, and thus the polishing disks dkb, dkc, to urge it downward as viewed in FIG. This urging force becomes the polishing pressure described later.

The headstock unit 2, and therefore the polishing disks dkb and dkc, can be moved at any speed in the x-axis direction by controlling the servomotor 43 and can be stopped at any position. dk
b and dkc are notches N of the semiconductor wafer W as described later.
And a linear reciprocating motion within the notch N.

A weight shelf 537 is provided on the side surface of the base 1. The weight shelf 537 is provided at a position just above the weight 535 when the headstock unit 2 moves to the left and the polishing disk dkc comes to a position facing the notch N. Here, since the polishing disk dkc polishes the notch N, when it moves downward in FIG. 5, the weight 535 comes to rest on the weight shelf 537, so that the load of the weight 535 is not applied to the headstock unit 2. Therefore, only the weight of the other weight 536 is applied. The reason why the load is changed between the notch bevel surface Sbn and the notch end surface Scn is that the polishing pressure for the notch bevel surface Sbn is preferably larger than the polishing pressure for the notch end surface Scn, but the present invention is It is not essential to adjust the polishing pressure for each surface, and the same polishing pressure can be maintained as in Example 2 described later.

In order to return the headstock unit 2 to its original position, the x table 50 is provided with a fluid pressure cylinder mechanism 541. The piston rod 543 of the fluid pressure cylinder mechanism 541 is slidably fitted in the hole of the engaging element 544 protruding from the lower side of the y table 20, and the flange 545 is provided on the side opposite to the piston 542 with the hole sandwiched therebetween.
Is fixed. When the piston 542 moves downward in FIG. 5, the flange 545 can freely slide without interfering with the hole, but when the piston 542 moves in the opposite direction, the flange 5 moves.
45 and the edge of the hole engage. Therefore, the weight 53
5, the y-table 20 is shown in FIG.
Seen at and moved upwards. By this movement, the headstock unit 2 is pulled back to the original position.

FIG. 6 is a right side view of the wafer chuck unit 3. An adjustment stand 33 for adjusting the height position with respect to the headstock unit 2 is attached to the base stand, and the adjustment stand 33 is provided with a pair of brackets 32. A shaft hole is provided above each bracket 32, and a tilt shaft 37 provided on the wafer chuck table 31 is fitted into the shaft hole. A segment-shaped worm wheel 34 is fixed to the tilting shaft 37.
A worm 35 driven by a tilting motor 36 is meshed with. When the tilt motor 36 is driven, the worm 3
5. Since the wafer chuck table 31 is tilted by the worm wheel 34 as shown by the dotted line in FIG. 6, the notch end surface Scn of the semiconductor wafer W supported by the wafer chuck table 31 in the horizontal state, Two
The notch bevel surface Sbn is polished in two inclined states.

The mirror polishing apparatus of the first embodiment operates as follows. FIG. 7 is a block diagram showing a control device 90 of the mirror polishing device PM and each unit controlled by the control device 90. In the initial state of the mirror polishing apparatus PM, the headstock unit 2 is at a position away from the wafer chuck unit 3 (retracted position). Further, the headstock unit 2 is in a state of moving to the left in FIG. 4, and the weight 535 is located right above the weight shelf 537. Further, the wafer chuck table 31 is in a horizontal state, and the previous semiconductor wafer W placed on the wafer chuck table 31 has already been polished and is waiting to be discharged.

When the control device 90 informs a higher-order control device (not shown) of this state, the transfer robot TR
Picks up the polished wafer from the wafer chuck table 31 and conveys it to the cassette C, then sucks and grips a new semiconductor wafer W from the positioning unit OU,
The wafer is conveyed onto the wafer chuck table 31 and placed on it. When a signal indicating that the semiconductor wafer W is placed on the wafer chuck table 31 is transmitted to the mirror polishing apparatus PM, the control device 90 operates the vacuum chuck (not shown) of the wafer chuck table 31 to move the semiconductor wafer W. It is held on the wafer chuck table 31.

The controller 90 is a fluid pressure cylinder mechanism 54.
1 is operated and the piston rod 543 is moved forward (moved downward in FIG. 5). Weights 535 and 53 in the retracted position
When the flange 545 that has received the load received from 6 moves forward, the receiving force disappears and the headstock unit 2 moves forward.

In parallel with this, the control device 90 drives the spindle motor 23 and causes the slurry supply device 91 to start the supply of the slurry. The weights 535 and 536 continue to descend, and then the weight 535 is placed on the weight shelf 537. From here, only the force by the weight 536 is applied to the headstock unit 2, and further, the headstock unit 2
Keeps moving forward. Eventually, the polishing disk dkc for polishing the notch end surface enters the notch N and starts polishing the notch end surface Scn. Since the load on the spindle motor 23 is constantly monitored by a load detector (not shown), the start of polishing is detected by a rapid increase in the load at the time of contact. Upon receiving the polishing start signal, the control device 90 starts the count of the timer 92 and controls the servo motor 43 to perform a slight forward / reverse rotation. The headstock unit 2 starts a small linear reciprocating motion by the forward and reverse rotations of the servomotor 43.

In FIG. 8, a polishing disk dkc is formed in the notch N.
It is explanatory drawing which shows a mode that (or dkb mentioned later) linearly reciprocates. By this linear reciprocating motion, the polishing disk dkc traverses along the bottom of the notch N, and the polishing pressure by the weight and the deformation of the polishing disk dkc combine to polish the inside of the notch N (notch end surface Scn) uniformly. .

When the predetermined polishing time has passed, the timer 9
2 sends a signal to the control device 90, and the control device 90 receives this signal to stop the linear reciprocating motion by the servo motor 43 and cause the fluid pressure cylinder mechanism 541 to start the backward movement. The fact that the piston rod 543 or the headstock unit 2 has reached the retracted end is detected by the detection means such as the limit switch 93, and the control device 90 stops the operation of the fluid pressure cylinder mechanism 541.

At the backward end, the control device 90 causes the servomotor 43
Of the semiconductor wafer W
The headstock unit 2 is moved to the right in FIG. 4 so as to be positioned in the front. Along with this command, the tilt motor 36 is driven to tilt the wafer chuck table 31, and the notch bevel surface Sbn is rotated to a position directly facing the polishing disk dkb.

The subsequent polishing operation of the notch bevel surface Sbn is the same as the polishing operation of the notch end surface Scn, and the description thereof will be omitted.
Linear reciprocating movement of the polishing disc dkb traverses along the bottom of the notch N, the polishing pressure due to the weight and the deformation of the polishing disc dkb combine with the notch N.
The inside (notch bevel surface Sbn) is evenly polished. However, since the weight 535 is no longer positioned above the weight shelf 537 due to the rightward movement of the headstock unit 2, the polishing pressure by the two weights 535 and 536 is entirely applied to the polishing surface. Therefore, the polishing pressure of the notch bevel surface Sbn is higher than that of the notch end surface.

When the polishing cycle of the notch bevel surface Sbn is completed, the headstock unit 2 is moved to the retracted end. Here, the notch bevel surface S on the opposite side (back side of the semiconductor wafer)
In order to polish bn, the controller 90 issues a command to rotate the wafer chuck table 31 to a position where it directly faces the polishing disk dkb. The subsequent operation is the same as when polishing the notch bevel surface Sbn on the front side, and therefore description thereof is omitted. In this case also, the linear reciprocating motion of the headstock unit 2 is performed, and the two weights 535 and 53 are further moved.
The polishing pressure of 6 is applied to the polishing surface.

When all the polishing of the notch N is completed, the controller 90 issues a command to return the mirror polishing apparatus PM to the initial state, returns to the initial state, and informs the upper controller that it is waiting for the loading of a new wafer. Inform. Accordingly, the polished semiconductor wafer W is transferred to the cassette C by the transfer robot TR, and a new semiconductor wafer W is transferred from the positioning unit OU to the wafer chuck table 3
1 is loaded.

Embodiment 2 As described above, in the mirror polishing apparatus PM of Embodiment 1, the drive for changing the positions of the polishing disks dkc and dkb to be used and the drive for performing the linear reciprocating motion of the tool spindle in the axial direction, and the polishing are performed. The drive for pressing the disk against the semiconductor wafer with a predetermined polishing pressure (and separating it from the disk) is given to the headstock unit 2. Then, the notch end surface Scn
The wafer chuck table is tiltable so that the notch bevel surface Sbn and the notch bevel surface Sbn face each other.

In Example 2, the used polishing disk dk was used.
The wafer chuck table 31 is provided with a drive for changing the positions of c and dkb and a drive for performing a linear reciprocating motion of the tool spindle in the axial direction. On the other hand, the wafer chuck table 31 can be tilted similarly to the first embodiment, and the drive for pressing the polishing disk against the semiconductor wafer with a predetermined polishing pressure (and releasing it) is the headstock unit 2
Is given to.

9 and 10 are a front view and a plan view, respectively, of the mirror polishing apparatus PM of the second embodiment. In these figures, the same reference numerals are used for members or units that are substantially equivalent to those in the first embodiment.

The mirror-polishing apparatus PM of this embodiment comprises a base 1,
A headstock unit 2 and a wafer chuck unit 3 are provided. The headstock unit 2 is provided with a spindle box 21, a tool spindle 22 rotatably supported by the spindle box 21, and a spindle motor 23 for rotationally driving the tool spindle 22. A pulley 24 is fixed to the rotary shaft of the spindle motor 23, and a pulley 26 is fixed to the tool spindle 22. The transmission belt 25 is fixed to both pulleys.
Have been passed over. The rotational force of the spindle motor 23 is transmitted to the pulley 24, the transmission belt 25, and the pulley 26 attached to the tool spindle 22, and the tool spindle 22 rotates. The rotation of the tool spindle 22 causes the polishing disks dkc and dkb attached thereto to rotate. Here, the polishing disk dkc is a disk for polishing the notch end surface Scn, and the polishing disk dkb is a disk for polishing the notch bevel surface Sbn.

On the base 1, a vertical feed unit 4 forming a guide feed mechanism in the axial direction of the tool spindle 22 (horizontal direction in FIG. 1, hereinafter referred to as x-axis direction) is also provided.
In another place above, a direction orthogonal to the feed direction of the vertical feed unit 4 (referred to as the front-back direction of the paper surface in FIG. 1 and the y-axis direction).
A lateral feed unit 5 is provided as a guide feed mechanism to the. The headstock unit 2 is provided on a y-table 20 which forms the transverse feed unit 5.

The vertical feed unit 4 is fixed on the base 1 and slide guides 41 parallel to each other along the x-axis direction.
1, 412 and these slide guides 411, 412
It consists of a slider that slides up and is provided below the x-table 50.

A servomotor 43 is fixed to the base 1 and a female screw member 45 is fixed below the x table 50. A feed screw 44, which is rotationally driven by the servomotor 43, is screwed into the female screw member 45. ing.

The transverse feed unit 5 is fixed on the base 1 and slide guides 51 parallel to each other along the y-axis direction.
1, 512 and sliders that slide on these slide guides 511 and 512 and that are provided below the y table 20.

One end of the wire 531 is fixed to the y-table 20, and the wire 531 is hung on the pulley 533 and the other end is fixed to the weight 535. Weight 5
The wire 35 is hung outside the base 1 by the wire 531. The pulley 533 is rotatably supported by a support member fixed to the base 1.

The y-table 20 receives a force in the y-axis direction corresponding to the weight of the weight 535, and a biasing force is applied to the tool spindle 22, and thus the polishing disks dkb and dkc, as shown in FIG. This urging force becomes the polishing pressure.

Since the y-table 20 can be moved / stopped at an arbitrary speed in the x-axis direction by controlling the servo motor 43, the polishing disks dkb and d can be moved.
The semiconductor wafer W can be moved to a position where the notches N face each other with respect to kc, and can be linearly reciprocated within the notches N.

In order to return the headstock unit 2 to its original position, the x table 50 is provided with a fluid pressure cylinder mechanism 541. The piston rod 543 of the fluid pressure cylinder mechanism 541 is slidably fitted in the hole of the engaging element 544 protruding from the lower side of the y table 20, and the flange 545 is provided on the side opposite to the piston 542 with the hole sandwiched therebetween.
Is fixed. When the piston 542 moves downward in FIG. 10, the flange 545 is free to slide without interfering with the hole, but when the piston 542 moves in the opposite direction, the flange 545 engages the edge of the hole. Therefore, the weight 53
The y-table 20 is moved upward as viewed in FIG. By this movement, the headstock unit 2 is pulled back to the original position.

The wafer chuck unit 3 is placed on the x-table 50. The wafer chuck table 31 provided in the wafer chuck unit 3 is in a horizontal state, and the notch end surface Sc of the semiconductor wafer W supported by the wafer chuck table 31 is horizontal.
n, and the notch bevel surface Sbn is polished in two inclined states. Since these configurations are similar to those shown in the first embodiment (FIG. 6), further description will be omitted.

In the mirror polishing apparatus of the second embodiment, except that the wafer chuck unit 3 side moves in the x-axis direction and linearly reciprocates, and that the polishing pressure is the same between the notch end surface Scn and the notch bevel surface Sbn. Since the operation is substantially the same as that of the first embodiment and can be read as it is, the further description will be omitted.

Example 3 The mirror surface polishing apparatus of Example 3 is of a type in which the wafer chuck table 31 of Example 1 does not tilt. In the first embodiment, the notch end surface Scn of the semiconductor wafer W
And notch bevel surface Sbn with respect to polishing disk dkc
The tilting operation of the wafer chuck table 31 is performed so that the polishing disk dkb and the polishing disk dkb face each other. However, in this embodiment, the tilting operation is not performed. Instead, the headstock is moved laterally (y-axis direction). ) And the height direction (z-axis direction).

This mirror polishing apparatus includes a headstock, a tool spindle, a wafer chuck table, vertical (x-axis direction) guide means, lateral (y-axis direction) guide means, height direction (z-axis direction) guide means, It is provided with vertical drive means, horizontal drive means and height drive means.

The tool spindle to which two (or one) polishing disks are attached is rotatable and is rotationally driven by the spindle drive source. The headstock is guided in the axial center direction (x-axis direction) of the spindle shaft by the vertical guide means, and is guided in the direction perpendicular to the spindle shaft (y-axis direction) by the horizontal guide means. The headstock is further provided with height guide means in a direction perpendicular to these directions (z
Guided in the axial direction).

FIG. 11 is an explanatory view showing the relationship between the movement and position of the polishing disks dkc, dkb and (the notch N of) the semiconductor wafer W in the third embodiment.

Each guide means is provided with a drive means, and the headstock is driven and moved in each direction. The headstock is moved in the lateral (y) and height (z) directions so that the end surface of the notch and the bevel surface of the semiconductor wafer supported on the wafer chuck table face the polishing disk, respectively. At the time of polishing, the notch and the polishing disk are biased by the biasing function so as to press each other, and the tip of the polishing disk is linearly reciprocated along the longitudinal (x) direction in the notch by the oscillation function (the drawing paper surface direction). Driven to do. In addition,
During polishing, the slurry is supplied to the polishing disk by the slurry supplying means.

Example 4 The mirror polishing apparatus of Example 4 is of a type in which the wafer chuck table 31 of Example 1 does not tilt. In the first embodiment, the notch end surface Scn of the semiconductor wafer W
And notch bevel surface Sbn with respect to polishing disk dkc
The tilting operation of the wafer chuck table 31 is performed so that the polishing disk dkb and the polishing disk dkb face each other. However, in this embodiment, the tilting operation is not performed. Instead, the wafer chuck table 31 is moved in the lateral direction (y. It is moved in the axial direction) and in the height direction (z-axis direction).

This mirror surface polishing apparatus comprises a headstock, a tool spindle, a wafer chuck table, a vertical (x-axis direction) guide means, a lateral (y-axis direction) guide means, a height direction (z-axis direction) guide means, It is provided with vertical drive means, horizontal drive means and height drive means.

The tool spindle to which two (or one) polishing disks are attached is rotatable and is rotationally driven by the spindle drive source. The wafer chuck table is guided in the axial direction (x-axis direction) of the spindle shaft by the vertical guide means, and is guided in the direction perpendicular to the spindle shaft (y-axis direction) by the horizontal guide means. The wafer chuck table is further guided by the height direction guiding means in a direction (z-axis direction) perpendicular to these directions.

FIG. 12 is an explanatory diagram showing the relationship between the movement and position of the polishing disks dkc, dkb and (the notch N of) the semiconductor wafer W in the fourth embodiment.

Each guide means is provided with a drive means, and the wafer chuck table is driven and moved in each direction. The wafer chuck table is moved in the lateral (y) and height (z) directions in order to make the notch end surface and bevel surface and the polishing disk face the semiconductor wafer supported on the wafer chuck table, respectively. . At the time of polishing, the notch and the polishing disk are pressed by the biasing function so as to press each other, and the oscillation function causes the tip of the polishing disk to
The semiconductor wafer is driven so as to make a linear reciprocating motion (in the drawing paper plane direction) along the longitudinal (x) direction within the notch. During polishing, the slurry is supplied to the polishing disk by the slurry supplying means.

[0068]

The deviation between the polishing disc and the notch increases with the increase in diameter of the semiconductor wafer W, which deteriorates the contact of the polishing disc and makes mirror polishing of the notch inefficient. According to the invention, by imparting a linear reciprocating motion to the polishing disk or the semiconductor wafer, the contact of the polishing disk with the wafer notch is improved, and as a result, the efficiency of mirror polishing of the wafer notch can be improved.

[Brief description of drawings]

1A and 1B are external views of a notched semiconductor wafer, in which FIG. 1A is a plan view thereof and FIG. 1B is a partial sectional view thereof.

FIG. 2 is an enlarged perspective view showing the vicinity of a notch of the semiconductor wafer.

FIG. 3 is a mirror polishing apparatus P in a semiconductor manufacturing system.
It is explanatory drawing which shows the outline of M and its periphery.

FIG. 4 is a front view for explaining a mirror polishing device (Example 1) of the present invention.

FIG. 5 is a plan view for explaining a mirror polishing apparatus (Example 1) of the present invention.

6 is a right side view of the wafer chuck unit 3. FIG.

FIG. 7 is a block diagram showing a controller 90 of the mirror polishing apparatus PM and each unit controlled by the controller 90.

FIG. 8 shows a polishing disk dkc (or d
It is explanatory drawing which shows a mode that kb) linearly reciprocates.

FIG. 9 is a front view for explaining the mirror-polishing device (second embodiment) of the present invention.

FIG. 10 is a plan view for explaining a mirror polishing apparatus (Example 2) of the present invention.

FIG. 11 shows polishing disks dkc and dk in Example 3.
It is explanatory drawing which showed the movement of b and the semiconductor wafer W (notch N), and the relationship of a position.

FIG. 12 shows polishing disks dkc and dk in Example 4.
It is explanatory drawing which showed the movement of b and the semiconductor wafer W (notch N), and the relationship of a position.

[Explanation of symbols]

1 base 2 Headstock unit 3 Wafer chuck unit 4 Vertical feed unit 5 Traverse unit C cassette N notch W semiconductor wafer 20 y table 21 Spindle box 22 Tool spindle 23 Spindle motor 24, 26 pulley 25 transmission belt 31 Wafer chuck table 32 bracket 33 Adjusting stand 34 Warm Wheel 35 Warm 36 Tilt motor 37 Tilt axis 43 Servo motor 44 lead screw 45 Female thread member 50 x table 90 Control device 91 Slurry supply device 92 timer 93 Limit switch OU positioning unit PM mirror polishing equipment Sb bevel surface Sc outer peripheral surface TR transport robot 411, 412, 511, 512 Slide guide 531 and 532 wires 533, 534 pulley 535,536 weight 537 weight shelf 541 Fluid pressure cylinder mechanism 542 piston 543 piston rod 544 Engagement element 545 flange Sbn notch bevel surface Scn Notch end face dkc, dkb polishing disc

Claims (9)

[Claims] 1. A headstock, a tool spindle for mounting a polishing disk, the tool spindle rotatably supported by the headstock, a spindle drive source for rotationally driving the tool spindle, and the spindle. Vertical guide means for guiding the spindle in the axial direction of the spindle shaft, lateral guide means for guiding the spindle stock in a direction perpendicular to the spindle shaft, and vertical guide means for the spindle stock. A longitudinal drive means for driving the head guide in a direction guided by the means, a lateral drive means for driving the headstock in a direction guided by the lateral guide means, and a table for supporting the wafer. A wafer chuck table tiltable about an axis in a plane including the guide direction of the vertical guide means and the guide direction of the horizontal guide means, and the wafer chuck table. In a mirror polishing apparatus for a wafer notch including: a table tilting means for tilting the wafer notch, the lateral driving means includes a wafer notch supported on the wafer chuck table and a polishing disk supported by the tool spindle. The vertical drive means has a biasing function of biasing the wafers against each other, and the tip of the polishing disk supported by the tool spindle is in the notch of the wafer supported on the wafer chuck table. A mirror polishing device for a wafer notch, which has an oscillation function for driving so as to perform linear reciprocating motion in the notch. 2. A headstock, a tool spindle for mounting a polishing disk, the tool spindle rotatably supported by the headstock, a spindle drive source for rotationally driving the tool spindle, and the main spindle. Lateral guide means for guiding the table in a direction perpendicular to the spindle axis, lateral drive means for driving the spindle table in the direction guided by the lateral guide means, and for supporting the wafer. A table, the wafer chuck table being tiltable around an in-plane axis including the axial direction of the spindle shaft and the guide direction of the lateral guide means, and the wafer chuck table including the wafer chuck table and the spindle shaft of the spindle shaft. Vertical guide means for guiding in the axial direction, and vertical drive means for driving the wafer chuck table in the direction guided by the vertical guide means. A wafer notch mirror polishing apparatus comprising: a table tilting means for tilting the wafer chuck table; and the lateral drive means supporting the wafer notch supported on the wafer chuck table and the tool spindle. And a polishing disc to be pressed against each other, the vertical drive means is supported by the tool spindle within a notch of a wafer supported on the wafer chuck table. A mirror polishing apparatus for a wafer notch, wherein the tip of the polishing disk has an oscillation function for driving so as to perform a linear reciprocating motion within the notch. 3. The mirror polishing apparatus for a wafer notch according to claim 1 or 2, wherein the wafer chuck table has a tilt angle for polishing the end surface of the notch by facing the polishing disk. And a mirror polishing device for a wafer notch, wherein the mirror polishing device is capable of tilting at least two angles, namely, another tilt angle for enabling polishing of the notch bevel surface by directly facing the polishing disk. 4. A headstock, a tool spindle for mounting a polishing disk, the tool spindle rotatably supported by the headstock, a spindle drive source for rotationally driving the tool spindle, and the spindle. Vertical guide means for guiding the spindle in the axial direction of the spindle shaft, lateral guide means for guiding the spindle stock in a direction perpendicular to the spindle shaft, and vertical guide means for the spindle stock. Means for guiding the headstock in a direction perpendicular to the two directions for guiding the headstock, and a direction for guiding the headstock in the direction in which the vertical guide means guides the headstock. Vertical drive means for driving, horizontal drive means for driving the headstock in a direction guided by the lateral guide means, and means for guiding the headstock by the height guide means In a mirror polishing apparatus for a wafer notch, which comprises a height driving means for driving the wafer chuck and a wafer chuck table for supporting the wafer, the lateral driving means comprises a wafer supported on the wafer chuck table. Has a biasing function of biasing the notch of the wafer and the polishing disk supported by the tool spindle so as to press each other, and the vertical driving means is provided in the notch of the wafer supported on the wafer chuck table. 2. A mirror polishing apparatus for a wafer notch, wherein the tip of the polishing disk supported by the tool spindle has an oscillation function for driving the tip so as to perform linear reciprocating motion in the notch. 5. The mirror notch polishing apparatus for a wafer notch according to claim 4, wherein the headstock includes the lateral driving means until the end surface of the notch and the notch bevel surface face the polishing disk, respectively. A mirror-polishing device for a wafer notch, which is moved by the height direction driving means. 6. A headstock, a tool spindle for mounting a polishing disk, the tool spindle being rotatably supported by the headstock, a spindle drive source for rotationally driving the tool spindle, and a wafer. Wafer chuck table for supporting, vertical guide means for guiding the headstock in the axial direction of the spindle shaft, and lateral guide for guiding the headstock in a direction perpendicular to the spindle shaft. Means, height direction guiding means for guiding the wafer chuck table in a direction perpendicular to two directions in which the longitudinal direction guiding means and the lateral direction guiding means respectively guide the headstock, and the main spindle. Vertical drive means for driving the base in the direction guided by the vertical guide means, and for driving the spindle base in the direction guided by the horizontal guide means In a mirror polishing apparatus for a wafer notch, which comprises a lateral direction driving means and a height direction driving means for driving the wafer chuck table in a direction guided by the height direction guiding means, the lateral direction driving means comprises: The notch of the wafer supported on the wafer chuck table and the polishing disk supported by the tool spindle have an urging function of urging them so that they are pressed against each other. In the notch of the wafer supported on the table, the tip of the polishing disk supported by the tool spindle has an oscillation function for driving so as to perform linear reciprocating motion in the notch. Mirror polishing device for wafer notch. 7. The wafer notch mirror polishing apparatus according to claim 6, wherein the wafer chuck table is provided with the lateral driving means up to a position where an end surface of the notch and a notch bevel surface respectively face the polishing disk. And a mirror-polishing device for a wafer notch, which is moved by the height driving means. 8. A mirror-polishing device for a wafer notch according to any one of claims 1 to 7, wherein the mirror-polishing device further supplies slurry to a polishing disk mounted on the tool spindle. A mirror-polishing device for a wafer notch, comprising a slurry supply means. 9. A mirror-polishing method for mirror-polishing a rotating polishing disk while pressing it into a notch of a wafer, wherein the polishing disk and the wafer are arranged between the polishing disk and the wafer in a direction of a rotation axis of the polishing disk. A method for mirror-polishing a wafer notch, characterized in that a linear reciprocating movement along the notch along the notch is applied and slurry is supplied to the polishing disk.