JPH07195265A - Polishing method of substrate - Google Patents

Abstract

PURPOSE:To perform a job for one-side polishing accurately in a mass-producing manner without forming a carrier into a thin type even in the case of a thinned substrate in thickness, in use of the mechanism of a double-side polishing device. CONSTITUTION:This polishing method consists of an upper polisher and a lower polisher 16 set up in a body and plural pieces of carriers 20, etc., formed with a mounting hole 24 being set up on top of this lower polisher 16 and holding a polished substrate 22, through which the polished substrate 22 held in the carriers 20 is polished. In this constitution, when the polished substrate 22 is held in the mounting hole 24 of the carrier 20, the polished substrate 22 is drawn in via a substrate mounting suction pad 28 stuck to a lower surface of a substrate mounting base 26, whereby a polishing surface of the polished substrate 22 are opposed to the lower grinder 16 before attachment. Subsequently, a specified weight 30 is mounted on top of the substrate mounting base 26, and the vertical motion and rotation of the upper polisher are all stopped, and then one side of the polished substrate 22 is polished by control over each rotational speed and machining time of the lower polisher 16 and the carrier 20.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for polishing a substrate, and more particularly to a method for polishing a substrate which is effective for polishing one side of a semiconductor substrate such as a wafer to form a flat uniform surface.

[0002]

2. Description of the Related Art Conventionally, various polishing apparatuses have been used for this type of substrate polishing method.
As disclosed in Japanese Patent No. 8568, there has been proposed a double-sided polishing apparatus for simultaneously polishing both surfaces of a plurality of substrates.

That is, a polishing apparatus for polishing both sides of a substrate is, as shown in FIG. 3, an upper surface plate 101 which rotates in one direction.
And a lower surface plate 102 that rotates in the opposite direction, and is placed between the upper surface plate 101 and the lower surface plate 102 to be processed 100
And a carrier 103 for holding

In the above structure, when polishing both sides of the substrate, the carrier 103 is revolved and revolved in the same direction as the lower platen 102 while the upper and lower platens and the work piece 10 are processed.
The predetermined polishing material 104 is supplied to the upper surface plate 101 during 0
A polishing method is generally used in which both surfaces of the workpiece 100 are polished while applying a processing pressure P to the.

Also, depending on the type of substrate, such as a substrate for a reflecting mirror or a glass substrate for a flat display,
When only one side of the substrate needs to be polished, a method of polishing using a dedicated polishing apparatus has been proposed, as disclosed in Japanese Patent Laid-Open No. 4-69159.

[0006]

However, in the above-mentioned substrate polishing apparatus, the polishing apparatus must be selected depending on the type of the substrate, and both the double-side polishing apparatus and the single-side polishing apparatus are required. However, there was a problem that the space and equipment costs increased.

When it is attempted to polish only one side of the substrate, particularly the other side of the substrate having a circuit or the like on one side, by using the one-side polishing apparatus, the template holding the substrate is not used. In order to protect the polishing surface, and to perform mass-production polishing, a separate device such as several polishing plates is required. To replace the double-sided polishing device with a single-sided polishing device, the thickness of the substrate There are various difficulties in control and holding method, and in particular, in order to hold a thin substrate and efficiently polish it in mass production, there are many problems such as that the thickness of the carrier must be thinner than the plate thickness of the substrate to be polished. There was a problem.

The present invention has been made in view of the problems of the prior art. The object of the present invention is to make the carrier thin, especially for a thin substrate, by using the mechanism of a double-side polishing apparatus. It is an object of the present invention to provide a single-sided polishing method for a substrate, which enables high-precision, mass-production and single-sided polishing without damaging one surface which is a non-polishing surface.

[0009]

In order to achieve the above object, a method for polishing a single side of a substrate according to the present invention comprises an upper polishing plate and a lower polishing plate installed on a main body, and an upper polishing plate on the upper surface of the lower polishing plate. In a double-sided polishing apparatus for a substrate, which is installed and has a plurality of carriers having a mounting hole for holding a substrate to be polished formed therein, and which polishes the substrate to be polished held in the carrier, When holding the substrate to be polished, the substrate to be polished is adsorbed via the adsorption pad for substrate attachment attached to the lower surface of the substrate mounting base,
After mounting the substrate to be polished with the polishing surface facing the lower polishing plate, place a predetermined weight on the upper surface of the substrate mounting base,
Vertical movement and rotation of the upper polishing platen are stopped, and one side of the substrate to be polished is polished by controlling the number of rotations and the processing time of the lower polishing platen and the carrier.

[0010]

In the above structure, when only one side of the substrate is polished by using the double-sided polishing apparatus for the substrate, the substrate mounting base is mounted in the mounting hole of the carrier installed on the upper surface of the lower polishing plate of the main body. The substrate to be polished is adsorbed through the substrate mounting suction pad fixed to the lower surface, and the polishing surface of the substrate to be polished is mounted so as to face the lower polishing plate. A predetermined weight corresponding to the plate thickness of the polishing substrate and the polishing processing pressure is placed, and the vertical movement and rotation of the upper polishing plate is stopped by the operation panel and control panel of the main unit, and the drive shaft, lower polishing plate, internal In addition to controlling the number of rotations of the gear and the processing time, the polishing is performed while supplying a predetermined polishing material, and the single-sided polishing of the substrate can be performed easily and in mass production.

Therefore, by using the mechanism of the double-sided polishing machine as it is, it is possible to accurately mass-produce the single-sided polishing process of a substrate having a thin plate thickness. Since it is not necessary to prepare a single-side polishing machine and the like, equipment costs and installation space are reduced, and the operation rate of the machine is improved, so that the economic effect is increased.

Further, in order to hold the substrate to be polished on the carrier, the substrate to be polished is sucked through the suction pad fixed to the substrate mounting base, and the suction pad has a predetermined compression elastic modulus and is sucked. Since only the surface is molded with resin that has suction cup-like porosity, the substrate to be polished can be easily held on the substrate mounting base by simply pressing the suction pad against the substrate to be polished, and easy to remove after polishing Is.

Further, the durability of the carrier is dramatically improved by making the thickness of the carrier larger than that of the substrate to be polished and making the mounting hole of the carrier approximately equal to or slightly larger than the substrate mounting base. At the same time, since the substrate mounting base is held in the carrier mounting hole, the end surface of the substrate to be polished does not come into contact with the edge of the carrier hole, and substrate damage such as chipping does not occur.

Further, by replacing at least one of the plurality of carriers with a dressing member, for example, a correction ring, it is possible to keep the flatness of the polishing surface constant.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a method for polishing a single side of a substrate according to the present invention will be described in detail below with reference to the drawings.

FIG. 1 is a sectional view of a double-side polishing apparatus for explaining one embodiment of the method for polishing a single side of a substrate according to the present invention, and FIG. 2 is a perspective view showing a main part of the double-side polishing apparatus.

In the figure, reference numeral 10 is a main body of a double-side polishing machine, and a drive shaft 12 having a sun gear 14 formed around it is rotatably installed at the center of the upper surface of the main body 10. A disk-shaped lower polishing disk 16 is rotatably mounted on the disk 12.

An internal gear 18 is installed on the outer peripheral portion of the lower polishing plate 16, and the sun gear 14 of the drive shaft 12 and the internal gear 18 are provided on the upper surface of the lower polishing plate 16. A plurality of carriers 20 having gears 32 that mesh with the gears 18 formed on the outer peripheral portion are installed at equal intervals.

The carrier 20 is provided with a plurality of vertically mounting holes 24 for holding a substrate 22 to be polished such as a glass substrate. When the substrate 22 to be polished is mounted in the mounting hole 24 of the carrier 20, as shown in FIG. 1, the substrate mounting base 26 is fixed to the lower surface of the substrate mounting base 26 having flatness by a double-sided tape or the like. The substrate 22 to be polished is sucked through the suction pad 28, and the substrate 22 is mounted so that the polishing surface of the substrate 22 faces the lower polishing plate 16.

Further, after mounting the substrate 22 to be polished in the mounting hole 24 of the carrier 20, by mounting a predetermined weight 30 on the upper surface of the substrate mounting base 26, the mounting work for polishing the substrate 22 to be polished on one side can be performed. Complete.

By the way, the suction pad 28 for fixing the substrate 22 to be polished to the lower surface of the substrate mounting base 26 is opened only on the suction surface in order to maintain the adhesion to the substrate 22 to be polished and a predetermined compression elastic modulus. It has a suction cup-like porosity, and is molded from a resin having innumerable closed pores in other parts.

Therefore, by pressing the suction surface of the suction pad 28 against the upper surface of the substrate 22 to be polished, the substrate 22 to be polished can be held securely on the lower surface of the substrate mounting base 26 with one touch, and at the same time, the substrate to be polished can be polished. The substrate 22 can be easily removed.

Further, unlike the conventional suede type cloth, the suction pad 28 has a strong suction force as described above, and the suction surface is less deteriorated even if the number of times of use is increased, and the suction pad 28 is further durable. Since it has excellent properties, it has a circuit engraved on the suction surface of the substrate 22 to be polished, has poor chamfering accuracy, has a deformed end surface, or has a specially shaped end surface. Also, it is possible to maintain a reliable holding force.

Further, since the pores other than the suction surface are closed pores, the non-polishing surface can be protected without the occurrence of stains on the polishing substrate suction adhesion surface due to the penetration of the abrasive into the suction pad.

Further, the carrier 20 holding the substrate 22 to be polished is provided with a plurality of mounting holes 24 independently, and a plurality of substrates 22 to be polished are provided in one carrier 20.
Can be set, and the polishing pressure can be adjusted by adjusting the weight 30 placed on the base mounting base 26. Therefore, even if the thickness of the substrate 22 to be polished varies, the polishing can be performed accurately. Processing can be performed.

Here, the drive shaft 12 and the lower polishing machine 16
The internal gear 18 and the internal gear 18 carry out their own rotational movements to hold the substrate 22 to be polished.
Is rotated by the rotation of the sun gear 14 and the internal gear 18 of the drive shaft 12 while revolving in the same direction as the lower polishing disc 16. For this,
The substrate 22 to be polished held in the mounting hole 24 of the carrier 20 is rotated, rotated, or revolved on the upper surface of the lower polishing platen 16.

An upper polishing plate (not shown) is mounted above the main body 10 so as to be vertically movable via an air cylinder for vertical movement, and the like.
6, the drive shaft 12, the internal gear 18, and the like are controlled in vertical movement and rotation by an operation panel and a control panel (not shown).

The operation in the case of polishing only one side of the substrate by using the double side polishing apparatus for the substrate in the above structure will be described.

First, a substrate fixed to the lower surface of the substrate mounting base 26 for holding the substrate 22 to be polished in the mounting hole 24 of the carrier 20 installed on the upper surface of the lower polishing plate 16 of the main body 10. The substrate 22 to be polished is sucked through the suction pads 28 for attachment, and the substrate 22 is mounted so that the polishing surface of the substrate 22 to be polished faces the lower polishing platen 16.

Next, after the substrate 22 to be polished is mounted in the mounting holes 24 of each carrier 20, the substrate mounting base 2 is mounted.
By placing a predetermined weight 30 corresponding to the plate thickness of the substrate 22 to be polished and the polishing processing pressure on the upper surface of 6, the setup for single-side polishing of the substrate 22 to be polished is completed.

Therefore, the operation panel and control panel of the main body 10 are used to stop the vertical movement and rotation of the upper polishing plate (not shown), and to rotate the drive shaft 12, the lower polishing plate 16, and the internal gear 18 for the number of revolutions and machining. The time is controlled, and the polishing process is performed while supplying a predetermined polishing material, so that one-side polishing of the substrate can be performed easily and in mass production.

According to the method for polishing one side of a substrate by using the double side polishing apparatus according to the present invention, it is possible to apply from the lapping process of the substrate to the polishing process which requires high precision. Even if a circuit is engraved on the back surface of the substrate, it is possible to carry out polishing without damaging the circuit portion.

Further, according to the present invention, since the double-side polishing machine is used, the number of sheets processed in one batch by the plurality of carriers 20 is large as compared with the processing using the dedicated single-side polishing machine, so that the productivity is improved. In addition to improving, even when polishing one surface of a plurality of types of substrates 22 to be polished due to differences in plate thickness,
Since the loading method is independent for each carrier 20, it is not necessary to perform different polishing processing for each plate thickness of the substrate 22 to be polished, or to perform desired polishing processing without preparing another carrier 20 or polishing plate. Is possible.

[0034]

Since the present invention is constructed as described above, it has the following effects.

(1) The mechanism of the double-side polishing machine can be used as it is, and in particular, the single-side polishing process of a thin substrate can be mass-produced with high precision, and the double-side polishing machine or the single-side polishing machine can be used depending on the substrate polishing method. This eliminates the need for preparation, reduces equipment costs and installation space, and improves the operating rate of the device, thereby increasing the economic effect.

(2) Since the thickness of the carrier for holding the substrate to be polished can be set sufficiently thicker than the thickness of the substrate to be polished, the durability of the carrier can be increased and the productivity can be improved.

(3) The substrate mounting base for holding the substrate to be polished in the mounting hole of the carrier may be a relatively thick flat-polished glass substrate, and the substrate to be polished is attached via a suction pad fixed to the substrate mounting base. Since the substrate to be polished is adsorbed, even if the substrate to be polished is thin, or the substrate with poor chamfering precision or the end face is deformed or has a special shape, the end face of the substrate to be polished comes into contact with the edge of the carrier hole. It is possible to reliably hold the substrate and perform the polishing process without damaging the substrate.

(4) The suction pad for mounting the substrate to be polished on the substrate mounting base has a predetermined compression elastic modulus and is made of resin having suction cup-like pores only on the suction surface. By simply pressing the suction pad, the substrate to be polished can be easily held on the substrate mounting base and can be easily removed after polishing.

(5) Since the suction pad has excellent holding power and has little deterioration even if the number of times of use increases, and has durability, even if the suction surface of the substrate to be polished has a circuit nick, it is surely not damaged. Can be held.

(6) Compared with the processing using a dedicated single-sided polishing device, the number of processed sheets in one batch is large with a plurality of carriers, so that productivity is improved and a plurality of types of substrates to be polished are produced due to the difference in plate thickness. Even when polishing one side, since it is an independent loading method for each carrier, there is no need to perform polishing processing for each plate thickness of the substrate to be polished, or to prepare another carrier or polishing plate, which is economical. The effect increases.

(7) By replacing at least one of the plurality of carriers with a dressing member, for example, a correction ring, the substrate is continuously polished, and at the same time, the flatness of the polishing plate is maintained. Therefore, the polishing accuracy of the substrate can be kept constant.

(8) Since the suction pad has an excellent holding power for the substrate to be polished, the substrate to be polished is warped due to the Twyman effect in the processing accompanied by the action of forming one surface such as a lap. It can be polished without being affected by various effects.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of essential parts of a double-sided polishing apparatus for explaining an example of a single-sided polishing method for a substrate according to the present invention.

FIG. 2 is a perspective view of essential parts of the double-sided polishing apparatus shown in FIG.

FIG. 3 is a cross-sectional view of a main part of a double-sided polishing device for explaining a polishing method using a conventional double-sided polishing device.

[Explanation of symbols]

 10 main body 12 drive shaft 14 sun gear 16 lower polishing plate 18 internal gear 20 carrier 22 substrate to be polished 24 mounting hole 26 substrate mounting base 28 suction pad 30 weight 32 gear

Claims (3)

[Claims] 1. An upper polishing plate and a lower polishing plate installed on a main body, and a plurality of carriers installed on an upper surface of the lower polishing plate and having mounting holes for holding a substrate to be polished. In a double-sided polishing apparatus for a substrate for polishing a substrate to be polished held in the carrier, for holding a substrate to be polished in a mounting hole of the carrier, for attaching a substrate attached to a lower surface of a substrate attachment base. After sucking the substrate to be polished through the suction pad of, and mounting the substrate to be polished with the polishing surface facing the lower polishing plate, place a predetermined weight on the upper surface of the substrate mounting base, A method for polishing a substrate, wherein the movement and rotation are stopped, and one side of the substrate to be polished is polished by controlling the number of rotations and the processing time of the lower polishing plate and the carrier. 2. The carrier is set to be thicker than the substrate to be polished and has at least one mounting hole substantially equal to the substrate mounting base,
2. The method of polishing a substrate according to claim 1, wherein the mounting hole of the carrier holds the substrate mounting base. 3. At least one of the plurality of carriers is replaced with a dressing member to correct the flatness of a polishing plate and at the same time, one side of the substrate to be polished is polished. The method for polishing a substrate according to claim 1.