JPS60259372A - Both face polishing - Google Patents

Abstract

PURPOSE:To improve the flatness through polishing by engaging the notch of work with the projection of carrier holding hole thereby blocking the rotation of work in said hole. CONSTITUTION:A carrier 10 gearing with an internal gear and a sun gear is spinned and revolved in the arrow direction (d) between upper and lower surface plates to polish the disc work 14 held in the holding hole 13 of carrier 10 by means of the upper and lower surface plates. Here, the projection 11 provided on the innercircumference of said hole 13 is engaged with a notch 15 made in the work 14 to block rotation of said work 14 in the holding hole 13 resulting in highly flat polishing of work 14.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to improvement of flatness and fine pitch waviness characteristics when precisely finishing both sides of a high-density magnetic disk substrate or a silicon wafer.

<Conventional example> In recent years, as the recording density of magnetic disk devices has become higher, the surface mechanical accuracy of the disk substrate has been reduced to a degree of flatness spm/surface (4”
), micro-vibration and Tee waviness accuracy of approximately 0.1 pm/4 mm is required. In addition, it is being considered that silicon wafers, which were conventionally only used on one side, can be used more effectively by precisely finishing both sides and mounting electronic components on both sides.

FIG. 4 is a plan view showing a conventional double-sided polygon and sink method for disk substrates. In Figure 4,
1 is the sun gear, 2 is the internal 4 pieces) arranged at cape intervals. A plurality of disc-shaped workpiece holding holes (hereinafter referred to as "holding holes") 7 are provided in the carrier 4 at equal intervals (four holes in the figure), and a disc-shaped workpiece 8 is provided in each of the holding holes 7.
is loosely fitted. In addition, the lower surface plate 3 is placed on top of the carrier 4.
An upper surface plate (not shown) having the same area as the upper surface plate is placed on the upper surface plate (not shown).

In the above configuration, for example, the upper and lower surface plates rotate in opposite directions to each other at a predetermined number of rotations; When the internal gear rotates in the direction of the arrow, the carrier 4 revolves around the sun gear in the direction of arrow D while rotating in the direction of arrow C, and is held by polishers (not shown) attached to the upper and lower surface plates. The workpiece 8 is bolished.

By the way, in the double-sided polishing method with the above configuration,
Since both the holding hole 7 and the workpiece 8 are disc-shaped, and the workpiece 8 is loosely fitted into the holding hole 7,
As shown in FIG. 5, the workpiece 8 rotates within the holding hole 7 in the direction of arrow B while moving in the direction of arrow d. As a result, variations in the amount of bolishing occur due to the difference in circumferential speed between the inner and outer circumferential sides of the workpiece 8, and for example, as shown in the cross-sectional view in FIG. The portion became tapered, resulting in poor flatness and causing slight pitch waviness.

A conventional method for preventing rotation of a workpiece in a holding hole is to cut off a part of a disc-shaped workpiece 20 and make the holding hole 21 slightly smaller than the workpiece 20, as shown in FIG. 7, for example. The workpiece 20 has a similar shape with a larger shape than the holding hole 21.
There is something inside that prevents it from rotating. However, a disk with a part cut off as described above cannot be used as a magnetic disk, and when used as a silicon wafer on which electronic components are mounted, a relatively large area is wasted. There is.

<Objective of the Invention> The present invention has been made in view of the above-mentioned prior art, and an object of the present invention is to realize flat processing without flatness and minute pitch warping.

<Configuration of the Invention> The configuration of the present invention that achieves this object includes upper and lower surface plates, and a carrier that meshes with an internal gear and a sun gear between these surface plates, and rotates and revolves the carrier. In the method of sandwiching and sinking a disk-shaped workpiece held by the upper and lower surface plates, at least one protrusion is provided on the inner periphery of the holding hole of the carrier; The structure is characterized in that a notch is provided in the workpiece in a shape, and the notch is engaged with the protrusion to perform poly-sinking.

<Embodiment> FIGS. 1(a) and 1(b) are plan views showing an embodiment of the present invention. In FIGS. 1(a) and 1(b), 10 is a carrier, 13 is a plurality of holding holes (four in the figure) provided in the carrier 10, and 11 is a protrusion provided on the inner periphery of the holding hole 13. 14 is a workpiece, 15 is a notch, and the notch 15 is machined to be slightly larger than the protrusion 11. Figure 2 shows a state in which the workpiece 14 is loosely fitted into the holding hole 13 of the carrier 10. FIG. According to FIG. 2, on the protrusion 11 provided on the inner circumference of the holding hole 13 of the carrier 10,
Since the notch 15 provided in the workpiece 14 is engaged and loosely fitted, the workpiece 14 rotates in the holding hole 13 even when the carrier 10 rotates and revolves in the direction of arrow d. Never.

In addition, in the above embodiment, one protrusion was provided on the inner periphery of the holding hole, and one notch was provided on the workpiece to engage with this protrusion, but the number of notches is not limited to one, but a plurality of notches may be provided. . For example, when the workpiece 14 is used as a magnetic disk substrate, as shown in the cross-sectional view in FIG. It is also possible to use In addition, in this embodiment, the case where the workpiece is a magnetic disk substrate or a silicon unicorn is explained, but the invention is not limited to this example. According to the present invention, the workpiece does not rotate in the holding hole, so the double-sided polyester material has high flatness and no minute pitch waviness.
A sink can be realized.

[Brief Description of the Drawings] Figures 1(a) and 1(b) are plan views of a carrier and a workpiece showing an embodiment of the present invention, and Figure 2 shows a workpiece loosely fitted into a holding hole of the carrier. FIG. 3 is a cross-sectional view of the workpiece used in a magnetic disk; FIG. 4 is a plan view of the conventional example; FIG. A cross-sectional view showing the finished state of the workpiece,
FIG. 7 is a plan view showing a conventional example of workpiece rotation prevention. DESCRIPTION OF SYMBOLS 10...Carrier, 11...Protrusion part, 13...Workpiece holding hole, 14...Workpiece, 15...Notch.

Claims (1)

[Claims] The method includes upper and lower surface plates, and a carrier that engages with an internal gear and a sun gear between these surface plates, and rotates and revolves the carrier to lower the disk-shaped workpiece held by the carrier to the upper surface. Hold it with a board and poly,
In the sinking method, at least one protrusion is provided on the inner periphery of the workpiece holding hole of the carrier, a notch is provided in the disc-shaped workpiece, and the notch is engaged with the protrusion. A polishing method characterized by polishing.