JPS60197364A - Polishing apparatus - Google Patents

Abstract

PURPOSE:To improve the machining precision of one-side surface by revolving a carrier holding a polished article at a prescribed speed by a guide gear set on the outer periphery and moving either of the upper and lower surface plates in reciprocation in the lateral direction, thus providing a uniform surface pressure onto the polished article having a large diameter. CONSTITUTION:A polished article 2 is fitted into each accommodation hole on a carrier 3 and loaded onto a lower surface plate 1, and an upper surface plate 5 is arranged so that the undersurface contacts with the uppersurface of the polished article 2. A guide gear 4 is driven, pouring abrasive agent onto the both surfaces of the polished article 2, and the carrier 3 is revolved at a prescribed speed in a certain direction, and the lower surface plate 1 is horizontally moved in reciprocation in the lateral direction by a driving mechanism. Therefore, the polished article 2 is revolved between the upper surface plate 1 which moves in reciprocation in the lateral direction and the fixed upper surface plate 5, and uniform polishing for the upper surface is permitted because of the sliding in a circular orbit having a certain angular speed, and the polishing with particularly high precision for the undersurface is permitted because of the sliding in a circular orbit having a certain angular speed and the reciprocative sliding in the lateral direction.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a polishing apparatus for polishing particularly one side of a thin plate such as a semiconductor wafer with high precision.

Traditionally, semiconductor wafer wrapping and poly
The one shown in FIG. 1 is known.

FIG. 1(A) shows a wafer 12 mounted on a block 11.
The block 11 with the wafers 12 mounted thereon is placed on the polishing cloth 14 which is stretched over the surface plate 13 shown in FIG. The surface plate 13 is connected to a drive device (not shown).1. Upper and lower axis O
It is designed to be rotated around . Then, cover the block 11 with the holder 15 and
Hold 1.

The holder 15 is connected to an elevating device (not shown) by a universal joint, so that it can be raised and lowered and rotated freely.

When polishing is performed, the polishing liquid is dropped onto the surface plate 13 while the surface plate 13 is rotated in the direction of the arrow in the figure by a drive device (not shown). As a result, the holder 15 is rotated by itself in the direction of the arrow in the figure, and the lower surface of the wafer 12 is rubbed against the upper surface of the polishing cloth 14 and polished using the polishing liquid.

However, this? With conventional polishing equipment, since polishing is performed in a quadrature pattern, uniform polishing cannot be achieved and it is difficult to obtain high flatness.

In addition, the work of attaching and detaching the wafers 12 in such an apparatus requires the work of attaching and peeling the wafers 12 to the block 11, which takes a considerable amount of time and is inefficient. Automation of work is becoming more widespread due to restrictions such as the size and weight of the block 11. Furthermore, as the diameter of the wafers 12 becomes larger, the number that can be attached to the block 11 decreases. In order to compensate for the decrease in efficiency caused by this, if the device is made larger, it becomes difficult to obtain horizontal rotation of the surface plate 3, which leads to a deterioration in machining accuracy.This invention was made in view of the above-mentioned circumstances. The purpose of the present invention is to provide a polishing device that can perform high-precision polishing by applying a uniform surface pressure to the object to be polished, and can easily cope with increasing the diameter of the object to be polished. .

The present invention will be explained below based on illustrated embodiments.

As shown in FIGS. 2(A) and 2(B), the flat lower surface plate 1 is movable horizontally in left and right directions, and is reciprocated left and right by a drive mechanism (not shown).

This lower surface plate! On the upper surface, the object to be polished (wafer) 2...
are loaded and placed in each accommodation hole of the carrier 3. This carrier 3 is disc-shaped and has teeth formed on its outer periphery. A plurality of guide gears 4 are disposed around the outer periphery of the carrier 3, and are connected to the carrier 3 and connected to an hwA motion device (not shown) to rotate the carrier 3. keeping. The object to be polished 2 is placed on the lower surface plate L.
...An upper surface plate 5 having the same shape as the lower surface plate 1 is fixedly provided on the upper surface.

In the polishing apparatus configured as described above, first, the object to be polished 2
... are loaded into each accommodation hole of the carrier 3 and placed on the lower surface plate 1. Next, the upper surface plate 5 is installed 4 so that its lower surface is in contact with the upper surface of the crushed object 2 . Then, while injecting abrasive into both surfaces of the object to be polished 2, the guide gear 4 is driven to rotate the carrier 3 in a constant direction at a predetermined speed. Furthermore, the lower surface plate 1 is horizontally reciprocated from side to side by a drive mechanism (not shown). Therefore, the object to be polished 2... rotates between the lower surface plate 1, which reciprocates from side to side, and the upper surface plate 5, which is fixed, and has a constant angular velocity with respect to its upper surface. Uniform polishing is achieved by sliding in a circular orbit with a constant angular velocity, and particularly high-precision polishing is performed on the lower surface by sliding in a circular orbit with a constant angular velocity and reciprocating sliding from side to side. . In this way, the object to be polished 2 is polished with extremely high processing accuracy such as flatness and parallelism.

By the way, various configurations can be used as the drive mechanism for reciprocating the lower surface plate 1 from side to side. For example, a rank extending horizontally is attached to the side of the lower surface plate 1, and a gear meshing with this rack is installed. It can be configured to drive in forward or reverse rotation.

Further, instead of the lower surface plate 10, the upper surface plate 5 may be configured to reciprocate from side to side.

However, the polishing apparatus of the present invention is not limited to this, and by changing the holding structure of the object to be polished, it is possible to easily perform vertical rotation and polishing. It can be polished using tilted linear motion.

As explained above, the polishing apparatus of the present invention rotates the carrier that holds the object to be polished in a constant direction at a predetermined speed using a guide gear provided around the outer circumference of the carrier.
One of the upper and lower surface plates in contact with the upper and lower surfaces of the object to be polished is made to repeatedly move back and forth to the left and right, and the object to be polished is always drawn in a circular orbit with a constant angular velocity.
Since both surfaces are always subjected to uniform sliding motion under uniform surface pressure, it is possible to polish one surface in particular with extremely good processing accuracy such as flatness and parallelism. be.

Even if the tt1 workpiece becomes larger, the carrier will not be rounded up or lose its balance, and as mentioned above, polishing will be performed with excellent processing accuracy, and the structure is extremely simple, so it will be useful in the future. It can also be easily adapted to automation.

[Brief explanation of the drawing]

Fig. 1 shows an example of a conventional polishing device, (A) is a plan view of a block equipped with a Ginever, (B) is a schematic side view of a different item, and Fig. 2 is a diagram of the polishing device of the present invention. An example is shown in which (A) is a schematic plan view thereof, and (B) is a schematic front view thereof. ...Carrier, 4...Guide gear, 5...Upper surface plate. Figure 1 (A) 2 (B)

Claims (1)

[Claims] A disc-shaped carrier that holds one or more objects to be polished and has teeth formed on its outer periphery, and rotates the carrier at a predetermined position about an upper and lower axis by meshing with the teeth on the outer periphery of the carrier. more than one guide gear, an upper surface plate and a lower surface plate arranged to sandwich the workpiece held in the carrier from above and below, and a drive that reciprocates either the upper surface plate or the lower surface plate to the left or right. A polishing device characterized by comprising a mechanism.