JPS62188669A - Polishing device - Google Patents

Abstract

PURPOSE:To increase the flow rate of a polishing liquid, reduce polishing time, and reduce the consumption of said polishing liquid by providing a guide member on the center of a polishing board of a polishing machine for a semiconductor wafer, etc. and guiding a supplied slurry type polishing liquid outwardly from the center. CONSTITUTION:A board body 10 is held on the bottom face 5 of a holding board 6 and brought into contact with the top face 3 of a polishing board 2, and supporting shafts 1, 4 are rotated to rotate the polishing board 2 and the holding board 6 in the directions of the arrows, while a slurry type polishing liquid is fed to a guide part 20 from the feed port 9 of a slurry liquid feed part 7. The guide member 20 is rotated together with the polishing board 2 to give a kinetic energy to the polishing liquid via a guide plate 22, causing the polishing liquid to flow radially outward from the rotation center at a large velocity. And, the polishing board 2 is rotated at such a speed of rotation as if the polishing liquid is in a laminar flow area, and the polishing liquid enters in between the top face 3 of the polishing board 2 and the board body 10, which, in turn, is polished in a short time, while reducing the consumption of the polishing liquid.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a polishing apparatus for polishing semiconductor wafers and the like.

[Conventional technology]

In general, when performing surface polishing of a plate such as the semiconductor wafer 71 whose surface is slightly uneven or bent, the plate is brought into contact with a plate-like polishing plate held by a holding plate, and the holding plate is held in place. While rotating the disk and the polishing disk, a slurry-like polishing liquid containing abrasive grains and an alkaline solution is supplied to the center of rotation K of the polishing disk, thereby polishing the surface of the plate.

FIGS. 5 and 6 are diagrams showing an example of a conventional polishing apparatus of this type. Reference numeral 1 in the figure is a cylindrical support shaft that is rotationally driven by a drive source (not shown). A disk-shaped polishing disk 2 with a flat upper surface is fixed to the upper part of the support shaft l. Above the polishing machine 2, there are provided four cylindrical support shafts 4.degree. 4 that are perpendicular to the top surface 3 of the polishing machine 2 and rotated by a drive source (not shown). These support shafts 4,
At the bottom of 4... is a disc-shaped holding plate 6 with a flat lower surface 5.
, 6... are fixed. The upper surface 3 of the polishing plate 2 and the lower surfaces 5, 5, . . . of the holding plates 6, 6, . . . are parallel to each other. A polishing slurry liquid supply section 7 is provided above the center of the top surface 3 of the polishing machine 2 to supply a slurry-like polishing liquid to the center of the top surface 3 of the polishing machine 2 . This polishing slurry liquid supply section 7 is formed of a cylindrical tube section 8 and a truncated conical tube-shaped supply port section 9 that is gradually inclined radially inward downward from its lower end. .

In order to perform flat surface polishing of a plate using the above-mentioned polishing device, first, the lower surfaces 5, 5 of the holding plates 6, 6, etc. shown in FIG.
@5.fC1 Holds the plates 10, 10, . . . of the workpiece. Then, the plates 10, 10, . . . are brought into contact with the upper surface 3 of the polishing machine 2 shown in FIG.
4..., while rotating the polishing plate 2 and the holding plates 6, 6..., the polishing station 1, which is provided above the center of the upper surface 3 of the polishing plate 2, is rotated. A slurry-like polishing liquid is supplied from the supply port 9 of 7 to the center of rotation of the polishing plate 2. This supplied slurry-like polishing liquid is caused by the twisting force of the upper surface 3 of the polishing disc 2, and the slurry-like polishing liquid is
It flows radially outwardly over the top surface 3 of the polishing disk 2 while rotating with the polishing disk 2 .

As a result, the slurry-like polishing liquid spreads between the plates 10° and 10°.
... and the upper surface 3 of the polishing machine 2, and the plates 10, 10, ... are polished by the slurry-like polishing liquid.

[Problem that the invention seeks to solve]

By the way, in the above polishing apparatus, the upper surface 3 of the polishing machine 2
Since kinetic energy is given to the slurry polishing liquid by the twisting force only, the flow velocity of the slurry polishing liquid is slow (
Therefore, there was a drawback that the polishing time and the amount of slurry-like polishing liquid used were longer than necessary.

The problem of this invention is to realize a polishing apparatus that reduces polishing time and the amount of slurry polishing liquid used.

[Means to solve the problem]

This invention focuses on the central part K of the polishing machine constituting the polishing device.
, a guide member is provided to guide the slurry-like polishing liquid outward from the center of rotation of the polishing plate.

〔Example〕

1 to 4 are diagrams showing one embodiment of the present invention. In these figures, the same elements as those shown in FIGS. 5 and 6 are designated by the same reference numerals.

The explanation of the parts having the same structure as the prize, FIG. 5, and FIG. 6 will be omitted.

The difference between the polishing apparatus shown in FIGS. 1 and 2 and the polishing apparatus shown in FIGS. 5 and 6 is that the slurry-like polishing liquid is applied to the center of the upper surface 3 of the polishing plate 2 by the rotation of the polishing plate 2. The point is that a guide member 20 is provided to guide outward from the center.

As shown in FIGS. 3 and 4, the guide member 20 includes a conical main body 21 whose generatrix is arcuate, and a conical main body 21 with a conical shape formed on the side surface of the conical main body 21.
It is formed of two guide plates 22, 22.... The guide plates 22, 22, . . . are curved thin plates, and these guide plates 22, 22, . . .
The curved surfaces are formed on the side surface of the conical main body 21 with the same pitch radially diagonally downward from the apex of the conical main body 21 and facing in the same direction in the circumferential direction of the conical main body 21. The guide member 20 is made of a corrosion-resistant and wear-resistant material.

To perform flat surface polishing of the plate 10° 10... using the polishing device installed at the center of the top surface 3 of the calendar board 2 as described above, first, Lower 11ii5 of the holding plates 6, 6... shown in FIG. 5... holds the plates 10, 10.... And the plates 10, 10
... is brought into contact with the upper surface 3 of the polishing plate 2 shown in FIG. , 6 . Guide member 2 provided in
A slurry-like polishing liquid is supplied to 0. The guide member 20 is
The rotating guide member 20/) rotates in the direction of the arrow together with the polishing machine 2, and the 11 rotation energy is applied to the slurry form through the guide plates 22, 22, . . . that constitute the guide member 20. It is given to the polishing fluid as kinetic energy.

The slurry-like polishing liquid given this kinetic energy is
It flows over the upper surface 3 of the polishing disk 2 radially outward from the center of rotation of the polishing disk 20 at a flow rate faster than the flow rate of the slurry-like polishing liquid shown in FIG. As a result, the slurry-like polishing liquid enters between the plate bodies 10, 10... and the upper surface 3 of the polishing machine 2, and the slurry-like polishing liquid causes the plate bodies 10, 10...
is polished. The rotation speed of the polishing plate 2 is such that the slurry-like polishing liquid is within the laminar region.

〔Effect of the invention〕

According to this invention, the guide member that guides the slurry-like polishing liquid supplied from the polishing slurry liquid supply section to the rotation center of the polishing machine constituting the polishing device outward from the rotation center of the polishing machine is attached to the polishing machine. Since the flow rate of the slurry polishing liquid is increased, the polishing time can be shortened and the amount of slurry polishing liquid used can be reduced.

[Brief explanation of drawings]

1 to 4 are views showing one embodiment of the present invention, in which FIG. 1 is a plan view of the polishing device, FIG. 2 is a front view of the polishing device, and FIG. 6 is a guide member. 4 is a front view of a guide member, FIG. 5 is a plan view of a conventional polishing device, and FIG. 6 is a front view of a conventional polishing device. 2... Polishing plate, 6... Holding plate, 7...
... Polishing slurry liquid supply section, 20 ... Guide member.

Claims (1)

[Claims] A workpiece is held by a holding plate, the workpiece is brought into contact with a polishing plate, and while the holding plate and the polishing plate are rotated, a slurry-like polishing liquid containing abrasive grains and alkaline liquid is applied to the polishing plate. In a polishing apparatus that polishes a workpiece by supplying a slurry liquid from a slurry supply unit to a rotation center of the polishing machine, the slurry polishing liquid supplied from the polishing slurry supply unit is supplied to the rotation center of the polishing machine. A polishing device characterized by being provided with a guide member that guides the polishing machine outward from the center of rotation.