JPH09254028A - Pusher for polishing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pusher for polishing device which displays sufficient cushioning action even when the pusher is brought into contact with a top ring. SOLUTION: A pusher 10 is set up in a position delivering a semiconductor wafer 100 to a top ring 75. The pusher 10 has a loading part 11 mounting the semiconductor wafer 100 and a driving part 21 vertically moving the loading part 11, and a cushion mechanism 31 is provided between the loading part 11 and the driving part 21. The cushion mechanism 31 is provided with a parallel moving mechanism 51, parallelly moving the loading part 11 in a vertical direction and an elastic spring mechanism 33 elastically energizing the loading part 11 in an upward direction.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pusher of a polishing apparatus used for delivering a polishing object to a top ring.

[0002]

2. Description of the Related Art Conventionally, in a process of manufacturing a semiconductor wafer, a polishing apparatus has been used to make the surface of the semiconductor wafer flat and mirror-finished.

This type of polishing apparatus has a turntable and a top ring, each of which rotates at an independent number of revolutions, and a semiconductor wafer held by the top ring is brought into contact with a polishing surface provided on the turntable. The surface of the wafer is polished.

On the other hand, the delivery of the semiconductor wafer to the top ring, that is, the delivery of the semiconductor wafer before polishing to the top ring and the delivery of the semiconductor wafer after polishing from the top ring are performed by pushers.

FIG. 4 is a schematic partial sectional view of a conventional pusher 110 of this type. As shown in the figure, the pusher 110 includes a mounting portion 12 on which the semiconductor wafer 150 is mounted.
0 and a drive unit 130 for vertically moving the mounting unit 120 by a shaft 131.

On the other hand, the top ring 140 has a disk shape and has a lower surface on which a suction surface 141 for sucking the semiconductor wafer 150 is formed.
Is provided. The top ring 140 is connected to the shaft 147 via a spherical ball bearing 143.
That is, the top ring 140 can swing about the ball bearing 143. Also, the shaft 147 around the ball bearing 143
An elastic member 145 is attached between the top ring 140 and the top ring 140.

When the semiconductor wafer 150 is transferred from the pusher 110 to the top ring 140, for example, the semiconductor wafer 150 transferred by a hand of a robot (not shown) is first mounted on the mounting portion 120 and then top. The ring 140 is moved to a position directly above the pusher 110 (the position shown in the figure), and then the driving unit 130 is driven to raise the mounting unit 120 so that its upper surface abuts the lower surface of the top ring 140. Then, the semiconductor wafer 150 is sucked onto the suction surface 141 of the top ring 140, and finally the driving unit 130 is driven to lower the mounting unit 120.

[0008]

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention By the way, the above-mentioned placing portion 1
It is necessary to prevent the shock generated when the upper surface of 20 is brought into contact with the lower surface of the top ring 140 from being transmitted to the semiconductor wafer 150. Conventionally, the shock is absorbed by the elastic member provided on the top ring 140. It was performed by the emitting member 145.

However, the elastic member 145 only buffers the shock against the swing of the top ring 140, and almost shock-absorbs the shock applied to the portion of the ball bearing 143 located on the rotation center axis of the top ring 140. Was not generated, and the impact applied to the central axis of rotation could not be absorbed.

The top surface of the mounting portion 120 is top ring 1
The impact does not occur at all if the lower surface of 40 is not brought into contact with the lower surface of the semiconductor wafer 40, but the semiconductor wafer 150 may come out of the gap between the two.

From the above, conventionally, the positioning adjustment of the mounting portion 120 with respect to the top ring 140 in the height direction is
It had to be done very accurately.

The present invention has been made in view of the above-mentioned points, and an object thereof is to exert a sufficient cushioning effect even when abutting against the top ring, whereby the positioning adjustment in the height direction between the top ring and the pusher is performed. It is an object of the present invention to provide a pusher of a polishing device that can make the above extremely easy.

[0013]

In order to solve the above problems, the present invention provides a top ring for holding a polishing object, a turntable for polishing the surface of the polishing object held by the top ring, and a top ring. In a polishing apparatus including a pusher installed at a position for delivering a polishing object, the pusher includes a mounting portion on which the polishing object is mounted, and a driving portion for vertically moving the mounting portion. And a buffer mechanism provided between the mounting part and the drive part, and further, the buffer mechanism includes a parallel movement mechanism for translating the mounting part in the vertical direction, and a mounting part upwardly. It is composed of an ejecting mechanism.

[0014]

Embodiments of the present invention will be described below in detail with reference to the drawings. First, the structure of the entire polishing apparatus to which the present invention is applied will be briefly described.
FIG. 3 is a schematic plan sectional view showing the polishing device 70 and a cleaning device 90 installed beside it.

As shown in FIG.
Is a polishing unit 77 with a turntable 73 installed in the center and top rings 75 attached on both sides.
And a dressing unit 81 to which a dressing tool 79 is attached, and the pusher 10 according to the present invention is installed next to the polishing unit 77.

On the other hand, the cleaning device 90 is provided with two work transfer robots 91 and 93 which are movable in the direction of arrow C in the center thereof, and primary and secondary cleaning machines 95 and 97 and a spin dryer are provided on one side thereof. (Or a spin dryer with a cleaning function) 99 is installed, and two work reversing machines 101 and 103 are installed on the other side.

Then, for example, when the cassette 105 containing the semiconductor wafer before polishing is set at the position shown in FIG. 3, the work transfer robot 93 moves from the cassette 105 to the first position.
A single semiconductor wafer is taken out and delivered to the work reversing machine 103, and after reversing the semiconductor wafer, the work transfer robot 91 places it on the pusher 10.

Next, the top ring 75 of the polishing unit 77 is rotated as shown by the alternate long and short dash line to rotate the pusher 1
Move right above 0.

The semiconductor wafer on the pusher 10 is pushed upward and approaches the lower surface of the top ring 75, and is attracted to the lower surface of the top ring 75 by vacuum attraction.

Top ring 75 that adsorbs a semiconductor wafer
Moves onto the turntable 73 and presses the semiconductor wafer against the polishing surface 74 on the surface of the turntable 73, and the surfaces are polished by the independently rotating turntable 73 and top ring 75, and then the top ring 75 is again removed. The semiconductor wafer after being moved to just above the pusher 10 is placed on the pusher 10.

The semiconductor wafer on the pusher 10 is transferred by the work transfer robot 91 to the work reversing machine 101 and reversed, and then cleaned by the primary and secondary cleaning machines 95 and 97, and then the spin dryer (or cleaning function). With spin dryer)
It is spin dried at 99 and returned to the cassette 105 by the work transfer robot 93.

FIG. 1 is a partially cutaway side view showing a schematic structure of the pusher 10. As shown in the figure, the pusher 10 includes a mounting portion 11 on which a semiconductor wafer is mounted.
And a drive unit 21 for vertically moving the mounting unit 11, and a buffer mechanism 31 between the mounting unit 11 and the driving unit 21.
Is provided. Hereinafter, each component will be described.

The mounting portion 11 is formed by projecting a side wall 15 upward from the periphery of the bottom plate 13 and providing a notch 17 for positioning and mounting a semiconductor wafer on the inner periphery of the upper end of the side wall 15. .

The drive unit 21 includes a drive unit main body 23 having a built-in drive motor, a shaft 25 protruding from the upper surface of the drive unit main body 23, and a bolt 27 at the upper end of the shaft 25.
And a plate member 29 fixed by.

When the motor inside the drive unit main body 23 is driven, the shaft 25 is driven in the vertical direction (direction of arrow A), and the plate member 29 is translated in the vertical direction.

Next, the buffer mechanism 31 is used for the positioning shaft 3
Repulsion mechanism 3 including 5 and coil spring 37
3, a parallel movement mechanism 51 including three shafts 53 (only two are shown in the figure) and a shaft receiver 55. The buffer mechanism 31 is the semiconductor wafer 1
00 is protected from the polishing liquid by the waterproof mechanisms 190 and 191 so that the polishing liquid adhered to 00 does not reach the buffer mechanism 31.

Here, the positioning shaft 35 is constructed by providing a flat plate-like stopper plate 41 on the upper end of a cylinder.
The lower end of the positioning shaft 35 is pierced through the center of the bottom plate 13 and the lower end thereof is fixed by the bolt 39.
9 is fixed.

The coil spring 37 is the shaft 35.
Is attached to surround the bottom plate 13 and the plate member 29.
It is attached so that it will spring in a direction that separates it.

Next, the shaft 53 has a cylindrical shape, and the lower end thereof is fixed to the plate member 29 with bolts 57.
Each shaft 53 is slidably inserted in a shaft receiver 55 fixed to the bottom plate 13. Since all the shaft receivers 55 are attached perpendicularly to the surface of the bottom plate 13, the surface of the bottom plate 13 slides in the direction perpendicular to the shafts 53. Therefore, the mounting portion 1
1 moves in the vertical direction.

Next, the operation of the pusher 10 will be described by the operation of passing the semiconductor wafer 100 from the top ring 75 to the pusher 110.

That is, in order to transfer the semiconductor wafer 100 adsorbed on the top ring 75 to the pusher 10, the top ring 75 is moved right above the pusher 10 as shown in FIG.

Next, the drive unit 21 is driven to raise the mounting unit 11 and the buffer mechanism 31 as a whole, and the mounting unit 1 is moved as shown in FIG.
The upper end surface of 1 contacts the outer peripheral lower surface of the top ring 75.

At this time, the placing portion 11 is the coil spring 3
Against the resilience of 7, the whole sinks slightly parallel. The coil spring 37 absorbs most of the impact when the mounting portion 11 and the top ring 75 contact each other, and the impact is not transmitted to the semiconductor wafer 100. In other words, by selecting an appropriate elastic force of the coil spring 37, almost no impact is applied to the semiconductor wafer 100.

Then, if the suction of the semiconductor wafer 100 by the top ring 75 is released in this state, the semiconductor wafer 100 is housed in the notch 17 of the mounting portion 11.

Then, the drive unit 21 is driven to lower the mounting unit 11 and the buffer mechanism 31 as a whole, and return them to the positions shown in FIG.
At this time, the placing portion 11 that has been pushed down is pushed up to a position where it abuts on the stopper plate 41 by the elastic force of the coil spring 37, and is positioned at that position.

By the way, contrary to the above operation, the pusher 1
When the semiconductor wafer 100 is transferred from 0 to the top ring 75, the pusher 10 may perform an operation reverse to the above operation.

[0037]

As described in detail above, according to the present invention, since the buffer mechanism including the parallel moving mechanism and the elastic mechanism is provided between the placing portion and the driving portion, the placing portion of the pusher can be The shock generated when it comes into contact with the top ring is sufficiently absorbed by the cushioning mechanism, and the shock is not transmitted to the object to be polished.
Further, even if the contact amount of the pusher with the top ring is changed a little, the impact is not transmitted to the object to be polished, so that the positioning adjustment between the top ring and the pusher does not have to be performed so strictly, and the adjustment work can be performed. It will be easier.

[Brief description of drawings]

FIG. 1 is a partially cutaway side view showing a schematic structure of a pusher 10.

FIG. 2 is a diagram showing a state in which a mounting portion 11 of the pusher 10 is raised.

FIG. 3 is a schematic plan sectional view showing a polishing device and a cleaning device.

FIG. 4 is a schematic partial cross-sectional view of a conventional pusher 110.

[Explanation of symbols]

 10 Pusher 11 Placement Part 21 Drive Unit 31 Buffer Mechanism 33 Repulsion Mechanism 51 Parallel Movement Mechanism 70 Polishing Device 73 Turntable 74 Polishing Surface 75 Top Ring 100 Semiconductor Wafer (Polished Object)

Claims (1)

[Claims] 1. A top ring for holding a polishing object, a turntable for polishing the surface of the polishing object held by the top ring, and a pusher installed at a position for delivering the polishing object to the top ring. In the polishing apparatus provided with, the pusher has a mounting part on which a polishing object is mounted, and a driving part for moving the mounting part up and down, and between the mounting part and the driving part. Is provided with a cushioning mechanism, and the cushioning mechanism is configured to include a parallel moving mechanism that translates the placing portion in the vertical direction and an elastic mechanism that resiliently pushes the placing portion upward. The pusher of the characteristic polishing device.