JP2001150311A - Circumference processing method and processing device for thin disc - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a processing method and a processing device capable of finishing a circumference portion of a thin disc at a high efficiency and a high quality by a fixed grinding grain processing tool. SOLUTION: In a finishing processing of a circumference portion of a thin disc, an outer periphery portion is processed with a grinding wheel 3 by a grinding device 10 and a notch portion on the outer periphery is processed with a polishing film 1 by a film polishing device 30. A grinding grain (silica grinding grain, barium carbonate grinding grain or cerium oxide grinding grain) causing a mechanochemical action is used for the grinding wheel 3 and the polishing film 1. A primary grain average grain diameter of the grinding grain is 0.8 μm-10 μm.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for processing a circumferential portion of a semiconductor wafer made of silicon, gallium arsenide, sapphire, or the like, or a thin disk made of a hard or brittle material such as quartz, glass, or Altic, or a metal material. It relates to a processing device.

[0002]

2. Description of the Related Art As a substrate material for a semiconductor device, a semiconductor wafer such as a silicon wafer is made of polycrystalline silicon as a raw material, starts with pulling up a single crystal silicon ingot, and goes through several processing steps to form a silicon wafer (bare silicon wafer). ). The manufacturing process is described in, for example, JP-A-5-13388.
Among several processes, there is a process of finishing the outer peripheral portion of the wafer.

Since the outer peripheral portion of the wafer is not a device forming portion unlike the flat portion (surface), high quality such as damage-free is not required.
After chamfering by rough grinding, only damage removal processing was performed by chemical etching. However, irregularities and microcracks remain on the outer peripheral portion of the wafer in this state. As a result, in the device manufacturing process, during wafer handling, cracks are generated from uneven portions, and residual microcracks cause problems such as generation of dust, and problems such as deterioration of wafer strength due to residual cracks. Will occur. In addition, problems such as abnormal film formation near the outer periphery of the wafer have been pointed out.

Therefore, as described in JP-A-5-13388, a polishing cloth is used after the chemical etching step.
Processing while supplying the abrasive slurry, that is,
Polishing finish is performed. By performing the polishing process, irregularities and microcracks on the outer peripheral portion of the wafer can be reduced to a level that does not cause a problem. Specifically, as the polishing cloth, a nonwoven fabric or a urethane foam resin, which is used in the polishing of the flat portion, is mainly used, and the abrasive slurry is also used in the polishing of the flat portion. And a colloidal silica slurry is mainly used.

Since the chemical etching process increases the irregularities on the outer peripheral portion of the wafer, a manufacturing method (described in JP-A-8-236489) in which this step is omitted has been proposed. It has been proposed to use an alkaline solution based on a solution such as sodium hydroxide instead of a mixed acid (a mixed solution of hydrofluoric acid, nitric acid, and acetic acid) that has a problem with respect to waste liquid treatment and the environment. In the latter case,
Since the unevenness of the outer peripheral portion of the wafer tends to increase,
The removal amount in the subsequent step, that is, the finishing process of the outer peripheral portion, increases. Therefore, in the finishing process of the outer peripheral portion, a method has been proposed in which a slight grinding process is performed prior to the polishing process to reduce the processing time (JP-A-9-57584, JP-A-9-57585). Gazette). By the way, various proposals have been made regarding a processing method, a processing apparatus, a processing tool, and a processing step as a technique related to the finish processing of the wafer outer peripheral portion.

First, in a system in which a polishing cloth is used as a tool and finish polishing is performed while supplying an abrasive slurry, Japanese Patent Application Laid-Open Nos. 5-6881 and 5-23959 describe processing methods and processing apparatuses. JP-A-5-123
No. 952, JP-A-5-243196, JP-A-7-50279, JP-A-9-94746,
JP-A-10-29142, JP-A-10-7154
9, JP-A-10-328989, JP-A-1
No. 1-70450, the technology disclosed in, for example,
As a polishing cloth tool, a technique disclosed in Japanese Patent Application Laid-Open No. 5-152260 is known. As a tool, there is also an invention using a tool made of cast iron or stainless steel having a higher hardness than a non-woven fabric or the like.However, since the tool hardness is high and it is difficult to finish a mirror surface, it is not a finishing grinding process but a rough grinding process. It is applied to the processing step (Japanese Unexamined Patent Publication No.
-71549).

On the other hand, a linear notch called an orientation flat is provided in the outer peripheral portion of the wafer as a reference for positioning and crystal orientation in a device manufacturing process. Recently, wafer 1
In order to increase the chip yield per chip, an arc-shaped or V-shaped notch called a notch has become mainstream as a smaller notch. The notch reduces the size of the notch, and thus has an advantage in that when the wafer is rotationally moved in various processing and drying processes, the motion balance is improved.

[0008] Since the orientation portion and the notch portion are different from the circumferential portion having a continuous shape, machining methods and tools different from the above techniques have been developed. For example, in the technique described in Japanese Patent Application Laid-Open No. 7-50279, the processing speed is improved by processing the wafer circumferential portion and the orientation flat portion using different polishing cloths. Regarding a processing method and a processing apparatus for finishing the notch, see JP-A-7-1322 and JP-A-8-1.
No. 68947, JP-A-8-236490, and the like. In each case, the finish polishing is performed while using a polishing cloth as a tool and supplying an abrasive slurry. However, in the technique described in JP-A-8-168947, a polishing belt or a polishing film may be used as a tool. Take into account.

As described above, the prior art relating to the method of performing a finish polishing process while supplying an abrasive slurry by using a polishing cloth as a tool has been described. There are problems such as environment, high running cost, and low processing efficiency, and application of a processing method using a fixed abrasive processing tool is being studied.

As a processing method using the fixed abrasive processing tool, a processing method and a processing apparatus using a polishing film as a tool have been proposed. As related related techniques, Japanese Patent Application Laid-Open Nos. 7-100748 and 7-17
Japanese Patent Application Laid-Open Nos. 1749, 7-237100, 8-168946, and the like are known.

Also, in the processing using a polishing film as a tool, inventions have been made on a processing method and a processing apparatus for processing an orientation flat portion and a notch portion (for example, Japanese Patent Application Laid-Open No. 7-100748, JP-A-7-124853, JP-A-8-118226, and JP-A-9-76148).

As another method using a fixed abrasive processing tool, there is a processing method using a grinding wheel as a tool.
As a related improved technique, Japanese Patent Laid-Open No. 6-2105 is disclosed.
No. 20, JP-A-7-58065 and JP-A-8-58065.
Japanese Patent Application Laid-Open Nos. 90401, 8-197400, 10-189508 and the like are known.

As described above, a free abrasive grain polishing method using a polishing cloth and an abrasive slurry has been conventionally used for finishing the outer peripheral portion of a semiconductor wafer.
Problems such as high running costs have become apparent. In addition, as described above, loose abrasive polishing is generally low in processing efficiency, and polishing and finishing of the outer peripheral portion of a wafer requires about 7 minutes per wafer, and other processing steps (for example, In the case of double-sided lapping, etc., it is understood that the processing efficiency is extremely poor, considering that it is 1 to 2 minutes.
Therefore, application of a fixed abrasive processing tool such as a polishing film or a grinding wheel having high processing efficiency has been desired.

[0014]

However, in the conventionally devised or developed method of finishing the outer peripheral portion of the wafer, the appropriateness of the tool to be used depending on the processing portion has not been sufficiently studied. That is, in any of the conventional machining methods, although the operation mode of the tool is different, the tool used is not changed between the circumferential portion and the notch portion of the wafer to achieve the appropriateness. In this case, the following problem occurs.

First, when a grinding wheel is used as a fixed abrasive processing tool, a tool speed of several hundred m / min or more is usually required in order to perform good processing. Therefore, a grinding wheel having a large diameter can be used for the wafer circumferential portion, so that a high tool speed can be realized. However, only a small-diameter grinding wheel can be used for the notch portion, and a sufficient tool speed can be obtained. Can not be secured. As a result, in the current situation, the grinding wheel is severely worn, the tool change cycle is too fast, the grinding wheel is likely to be clogged, the notch shape accuracy is likely to be degraded, and the machining surface quality of the notch is There is a problem that it is extremely bad. It is also conceivable to process the notch portion using a large-diameter grinding wheel, but in this case, it is necessary to take a tool action form in which the rotation axis of the grinding wheel is parallel to the wafer surface. However, including the notch, the circumference of the wafer is chamfered, and in order to process the wafer surface with the rotation axis of the grinding wheel parallel, the upper part of the chamfered part, the center part, and the lower part, There is a need to perform grinding in three places, and it is not possible to shorten the processing time.

On the other hand, a polishing film is
Since the abrasive grain holding strength and the tool rigidity are low and the tool speed is relatively low, the machining removal ability is inferior. as a result,
When applied to the finish processing of the entire outer peripheral portion of the wafer, the processing time cannot be reduced.

Not only the semiconductor wafer but also a disk made of a hard and brittle material such as quartz, glass, and AlTiC or a metal material, and the processing of the circumferential portion of the wafer have the same problems as described above. In a glass disk or the like having a donut shape, the same problem occurs in the inner peripheral processing of a small-diameter hole as in the above-described processing of forming the notch on the outer circumference. In recent years, regarding the processing of small diameter holes such as glass discs,
For the purpose of preventing dust generation and improving the accuracy of attachment to the disk drive, polishing processing is performed with loose abrasive grains, and there are concerns about waste liquid treatment, poor processing environment, high running cost, low processing efficiency. Have been. Therefore, it is conceivable to perform small-diameter hole machining with a grinding wheel, but, like in the notch machining of the outer circumferential portion, only a small-diameter grinding wheel can be used, and a sufficient tool speed cannot be secured. There is a problem that the wear of the grindstone is severe.

Further, JP-A-9-123050, JP-A-10-44007, and JP-A-11-70450
According to the description in Japanese Patent Application Laid-Open No. H10-157, there is also pointed out a problem that a processing mark corresponding to a running direction of a polishing cloth or a polishing film is formed on a processing surface.

An object of the present invention is to improve such a problem and to provide a processing method and a processing apparatus which are suitable for improving the processing efficiency and the surface quality of a thin-walled disk in the peripheral processing. is there.

[0020]

According to the first aspect of the present invention,
A method for finishing a circumferential portion of a thin-walled disk, wherein a grinding step of processing an outer peripheral portion of the thin-walled disk with a grinding wheel and a polishing step of processing a notched portion or an inner peripheral portion on the outer periphery of the thin-walled disk with a polishing film. And that it has

According to this method, the conventional free abrasive polishing can be replaced with processing using a fixed abrasive processing tool, so that problems such as waste liquid treatment, high running cost, and low processing efficiency can be solved.

In the case of processing the outer peripheral portion of a thin disk with the grinding wheel, a large-diameter grinding wheel can be used, so that a sufficiently high tool speed can be secured and good processing can be realized. . Also, instead of polishing film,
Since a grinding wheel is used, high processing efficiency can be achieved.

The notch on the outer periphery or the inner periphery is processed with a polishing film, whereby similarly favorable processing can be realized. The advantages of applying the film polishing to the processing of the notch or the inner peripheral portion and the reason why good processing can be realized are as follows. First, since the polishing film has flexibility, unlike a grinding wheel, it is suitable for processing complicated shapes such as notches, or portions where the usable tool diameter such as the inner peripheral portion is smaller than the outer peripheral portion. ing. Further, the tool speed cannot be set higher than that of a grinding wheel, but it is easier to obtain a higher abrasive ratio than that of a grinding wheel, so that a good surface quality can be achieved. When the abrasive ratio is high, clogging is likely to occur.However, unlike a grinding wheel, a polishing film can be used to feed out a long film and always work while using the new surface of the film. can do.

As described above, the grinding wheel is provided on the outer peripheral portion of the thin disk, the notch portion having a small area but a complicated shape as compared with the outer peripheral portion of the thin disk, or the usable tool diameter is smaller than that of the outer peripheral portion. By using a polishing film in the inner peripheral portion for processing, a high processing surface quality equivalent to polishing finish can be achieved with high processing efficiency.

According to a second aspect of the present invention, in the first aspect, in the first grinding step, a grinding wheel using abrasive grains having a mechanochemical effect is used.

Japanese Patent Application No. 10-366863, Japanese Patent Application No. 11
As proposed in Japanese Patent Application No. 082171, and Japanese Patent Application No. 11-237467, silicon can be subjected to mechanochemical processing with a fixed abrasive processing tool using silica as abrasive grains, and high quality processing equivalent to polishing finish can be performed. It has been found that a surface can be obtained. Examples of abrasive grains that produce a mechanochemical effect include barium carbonate abrasive grains in addition to silica abrasive grains.
Further, for example, when glass is to be processed, cerium oxide abrasive grains or the like can be used.

In the technique described in Japanese Patent Application Laid-Open No. 8-90401, a grindstone for mirror-finishing the outer peripheral portion of a wafer is used.
A grindstone using silica as abrasive grains has been proposed, but a water-soluble working fluid is used as a method of use. The inventors have confirmed that when a water-soluble processing liquid is used, the mechanochemical effect of silica on silicon is suppressed, and the processing removal effect is almost lost, and it is extremely difficult to realize this.
In the technique described in Japanese Patent Application Laid-Open No. 8-197400, a fine abrasive grindstone using an elastic binder is also proposed as a grindstone for mirror finishing of the outer peripheral portion of the wafer. Therefore, realization of mechanochemical processing is indispensable, and as described in JP-A-8-197400, it is extremely difficult to achieve a high-quality processed surface based on a mechanical removing action.

A third aspect of the present invention is characterized in that, in the first aspect, in the polishing step, a polishing film using abrasive grains having a mechanochemical effect is used.

A fourth aspect of the present invention is characterized in that, in the second and third aspects, the average primary particle diameter of the abrasive grains for producing the mechanochemical action is 0.8 nm to 10 μm.

If the average grain size of the abrasive grains producing the mechanochemical action is less than 0.8 nm, the mechanical action becomes too small, so that a desired mechanochemical action can be generated. I can't get it. On the other hand, if the average grain size of the abrasive grains that cause the mechanochemical action exceeds 10 μm, the mechanical action is too strong, and there is a possibility that processing damage may occur on the outer peripheral portion of the disk as the workpiece.

A fifth aspect of the present invention is characterized in that, in the first to fourth aspects, the grinding step and the polishing step are performed in a dry manner.

By performing the processing in a dry manner,
4 can perform the mechanochemical processing using the abrasive grains, and at the same time, can solve problems such as deterioration of the working environment and running cost due to the supply of the processing liquid.

According to a sixth aspect of the present invention, there is provided a processing apparatus for finishing a circumferential portion of a thin disk, comprising: a grinding apparatus for processing an outer peripheral portion of the thin disk with a grinding wheel; A film polishing apparatus for processing the notched portion or the inner peripheral portion with a polishing film, and a transfer device for moving the thin disk between the grinding apparatus and the film polishing apparatus, positioning and fixing the thin disk, and It has special features.

The outer peripheral portion of the thin disk is processed by a grinding wheel, while the notch portion (notch portion) or the inner peripheral portion is processed by a polishing film to finish the peripheral portion of the thin disk with high efficiency. , High quality and high efficiency.

The seventh aspect of the present invention is characterized in that, in the sixth aspect, abrasive grains that cause a mechanochemical action are used for the grinding wheel and the polishing film.

An eighth aspect of the present invention is characterized in that, in the seventh aspect, the average primary particle diameter of the abrasive grains producing the mechanochemical action is 0.8 nm to 10 μm.

[0037]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of the present invention will be described with reference to the drawings. However, the present invention is not limited to this embodiment. A wide range of applications for processing methods and processing equipment for finishing the peripheral part of thin disks (disks, wafers, etc.) made of hard or brittle materials such as semiconductor wafers, quartz, glass, Altic, etc. or metal materials by fixed abrasive processing Is also included.

<Structure> FIG. 1 shows a schematic structure of a processing apparatus according to an embodiment of the present invention.

The processing device 100 includes a grinding device (grinding device) 10, a transport device 20, and a film polishing device (film polishing device) 30. Each of the devices 10, 20, 30 is arranged in an independent block. , Can be independently controlled by a control unit (not shown).

The grinding device 10 includes a work moving section 11 and a grinding section 12, and both the work moving section 11 and the grinding section 12 are set on a base.

In the work moving section 11, a slide table 14 is provided on a pair of guide rails 13 provided on a base so as to be slidable in the horizontal direction (the direction of the arrow). The mechanism for moving the slide table 14 can be realized by using, for example, a configuration in which a guide-integrated ball screw is rotated by driving a motor, a configuration using a rack and a pinion, and the like.

A work rotation motor 15 connected to a work table 16 is fixed on the slide table 14. A plurality of vacuum suction pads (not shown) are provided on the work table 16 so that a disk-shaped work (disk, wafer, etc.) 2 positioned and mounted on the table by the transfer device 20 is suction-fixed from below the table. It is composed.

In the grinding section 12, a pair of guide rails (not shown) is provided vertically on a mount 17 on one side of the guide rail 13 (opposite side of the transfer device 20), and a slider 50 is mounted on the guide rail. It is slidably supported. The lifting mechanism for moving the slider 50 includes:
For example, it can be realized by using a configuration in which a guide-integrated ball screw is rotated by driving a motor, a configuration using a rack and a pinion, and the like.

A grinding motor 19 having a rotary shaft connected to the grinding wheel 3 is fixed to the slider 50.

The grinding wheel 3 is formed of a binder mixture of resin, ceramics, metal, etc. containing abrasive particles which cause mechanochemical action, or formed solely of abrasive particles. Is set to 0.8 nm to 10 μm. This is because the average grain size of the abrasive grains used is 0.8
When the average particle diameter is less than 10 nm, the mechanical action becomes too small, a desired mechanochemical action can be generated, and the processing amount cannot be obtained. If it exceeds, the mechanical action is too strong, and there is a possibility that processing damage may occur on the outer peripheral portion of the disk as a workpiece. The method for producing a grinding wheel containing silica abrasive grains is as described in detail in Japanese Patent Application No. 11-237467. In this embodiment, as shown in FIG. 2, the grinding wheel 3 is formed in a layer shape, and a plurality of tapered grooves 3a to 3c are formed on the peripheral surface of the cylinder. At the time of grinding, the circumferential portion of the disk 2 is brought into contact with the tapered portions of the grooves 3a to 3c for grinding, and the grooves 3a to 3c are appropriately changed and used for wear of the grinding wheel 3.

In addition, as the abrasive grains for producing the mechanochemical action, silica abrasive grains are used when the object to be processed is a silicon wafer. However, the present invention is not limited to this, and barium carbonate abrasive grains may be used. In the case where glass is to be processed, for example, cerium oxide abrasive grains may be used.

The transfer device 20 has a pivot axis on the floor surface, a pivot portion 21 for rotating and moving the robot hand (link portion 23) in the horizontal direction, and a slider disposed on the pivot portion 21 to move the link portion 23 up and down. Part 22, pivot part 21
And a link portion 23 having one end connected to the slider portion 22 and a suction pad at the other end.

The pivot portion 21 is connected to the link portion 23 via a gear mechanism by applying a torque generated from, for example, a DC servomotor.
Communicate to At this time, the rotation angle of the link unit 23 is extracted as an electric signal, and is fed back to the control unit.

The slider section 22 rotates a ball screw, a long screw, or the like by driving a DC servo motor, for example, and converts the rotation into a linear motion via a slide bearing or a rod. At this time, the amount of movement (movement distance) of the link unit 23 is extracted as an electric signal, and is fed back to the control unit.

The link section 23 realizes a manipulation function such as movement, positioning, and fixing of the disk 2 by feedback control based on the driving amounts of the pivot section 21 and the slider section 22. That is, the disc 2 conveyed by a belt conveyor or the like from a previous process (not shown) is
The wafer 2 is sucked one by one and moved and placed on the work table 16 of the grinding device 10, while the disk 2 after the outer peripheral portion is ground is attracted and moved and placed on the work table 37 of the polishing device 30.

The film polishing apparatus 30 includes a work moving unit 3
3 and a polishing section 32. The work moving section 33 and the polishing section 32 are both set on a base.

In the work moving section 33, a slide table 35 is provided slidably in a horizontal direction (arrow direction) on a pair of guide rails 34 provided on a base. The mechanism for moving the slide table 35 is as follows.
As described above, for example, it can be realized by using a configuration in which a guide-integrated ball screw is rotated by a motor drive, a configuration using a rack and a pinion, and the like.

A work rotation motor (for example, a stepping motor) 36 connected to the work table 37 is fixed on the slide table 35. The work table 37 is provided with a plurality of vacuum suction pads (not shown), and is configured so that the disk 2 positioned and mounted on the table by the transfer device 20 is suction-fixed from below the table.

In the polishing section 32, the tape-shaped polishing film 1 is wound around a pay-out reel 40 so as to be able to be fed out, and the fed-out polishing film 1 is taken up by a take-up reel 39 via a pressure roller 41. The drive motors (not shown) of the pay-out reel 40 and the take-up reel 39 are both configured to be rotatable in the forward and reverse directions. By controlling both drive motors synchronously, the polishing film 1 reciprocates up and down, and the work table 37 The notch 2a (shown in FIG. 3) of the disk 2 which is positioned and fixed at a predetermined position is polished while being pressed.

As shown in FIG. 4, the polishing film 1 is made of a binder resin 1b containing abrasive grains 1c which cause mechanochemical action.
Is applied on a resin film 1a serving as a base material, dried and cured, and the average particle size of the abrasive grains is set to 0.8 nm to 10 μm for the above-described reason. In addition,
A method for producing a polishing film containing silica abrasive grains is disclosed in Japanese Patent Application No. Hei.
It is as detailed in 1-237467. Also,
As the abrasive grains that cause the mechanochemical action, silica abrasive grains are used when the processing target is a silicon wafer. However, the present invention is not limited to this. For example, barium carbonate abrasive grains may be used.
When the object to be processed is glass, for example, cerium oxide abrasive grains or the like may be used. During polishing, the abrasive grain side (front side) of the polishing film 1 is pressed against the notch 2a of the disk 2 by the pressure roller 41, and the polishing film 1 is moved up and down to polish the notch 2a. Here, the width (tape width) of the polishing film 1 is set slightly wider than the width of the notch 2a.

The pressing unit 31 is provided on the substrate side (back side) of the polishing film 1 and rotatably supports the pressing roller 41; an air cylinder 38 capable of moving the frame in the left-right direction; And a swing mechanism for turning and swinging the frame in the front-rear direction (the direction perpendicular to the running direction of the polishing film 1) by driving a drive motor (not shown). The pressure roller 41 is made of an elastic body and has an outer peripheral shape,
The thickness and the like are formed so as to correspond to the shape of the notch 2a. The air cylinder 38 is controlled by the control unit so that the polishing pressure of the polishing film 1 becomes a predetermined value.
During the polishing process, the polishing film 1 is pressed against the disk 2 by pressing the frame.

The detailed constructions of the above-described grinding device 10 and film polishing device 30 are described in Japanese Patent Application No. 8-9040.
No. 1 and Japanese Patent Application No. 9-76148.

As for the positioning of the work (disk 2), the upper surfaces of the work tables 16 and 37 are image-recognized by a visual sensor (for example, a TV camera, a CCD image sensor, a vidicon, etc.). Image processing and the work tables 16 and 37
The center coordinates of the work are obtained based on a mark provided in advance, and the movement of the link 23 is controlled based on the coordinates. On the other hand, a visual sensor is attached to the tip of the link 23 to recognize the image of the work to be held. The positioning mechanism may be configured to finely adjust the relative positions of the work table 16 and the work table 37. The configuration of this type of positioning mechanism is
It is disclosed in detail in Japanese Patent Application No. 10-23914.

<Processing Method> Here, a method of finishing the outer peripheral portion of the disk in this embodiment will be described. The disk 2 to be processed has at least a chamfering step as a previous step,
It is assumed that a lapping step and an etching step have been performed.

The processing method of the present embodiment includes a grinding step of processing the circumferential portion of the disk 2 with the grinding wheel 3, a polishing step of processing a notch on the circumference of the disk 2 with the polishing film 1, including.

First, the grinding step will be described.

In the transfer device 20, the discs 2 conveyed by the belt conveyor or the like from the previous process are sucked one by one by the suction pads of the link portion 23, and are moved and placed on the work table 16 of the grinding device 10. At this time, the slide table 14 is locked by a lock mechanism (not shown) so as to stop at a predetermined position.
Positioning is performed so that the center of rotation and the center of the disk 2 coincide.

Next, in the grinding device 10, the disc 2, which has been aligned, is suctioned and fixed by the suction pad on the work table 16, the slide table 14 and the slider 50 are moved, and the grinding wheel 3 and the disc 2 are moved to predetermined positions. Position.

Next, the work table 16 and the grinding wheel 3 are each rotated, and the slide table 14 is moved in the horizontal direction (on the grinding wheel 3 side).
Is brought into contact with any of the grooves 3a to 3c of the grinding wheel 3, and the slide table 14 is further moved by a predetermined amount to mirror-process the chamfered portion of the disk 2.

After the mirror finishing (grinding) is completed, the rotation of the work table 16 and the grinding wheel 3 is stopped, and the slide table 14 is moved and stopped in the horizontal direction (on the side of the transfer device 20). Wait.

Next, the polishing step will be described.

After the grinding, the link portion 23 is rotated by the pivot portion 21 of the transfer device 20 toward the grinding device 10 by a predetermined amount, and the slide portion 22 lowers the link portion 23 by a predetermined amount. With this rotation / down movement, the link 2
Since the suction pad No. 3 comes into contact with the disk 2 on the work table 16, the disk 2 is sucked from above by the suction pad of the link portion 23, and the suction from below the work table 16 is released.

Next, after the link portion 23 is raised by a predetermined amount by the slide portion 22, the link portion 23 is rotated by the pivot portion 21 toward the film polishing apparatus 30 by a predetermined amount. Further, the link portion 23 is lowered by a predetermined amount by the slide portion 22, and the disk 2 sucked by the link portion 23 is moved and placed on the work table 37. At this time, the center of rotation of the work table 37 coincides with the center of the disk 2, and the outer periphery of the pressure roller 41 and the notch 2 of the disk 2
Align so that a faces each other. At this time, the work table 37 is rotated as necessary.

Next, in the film polishing apparatus 30, the disc 2 which has been positioned by the suction pad of the work table 37 is sucked and fixed from below, and
Release adsorption. Thereafter, the link portion 23 is raised by a predetermined amount by the slide portion 22, and the link portion 23 is further rotated by the pivot portion 21 toward the grinding device 10 by a predetermined amount.

Next, the slide table 35 is moved to the polishing section 3.
After moving the disk 2 toward the pressure roller 41 by moving the disk 2 by a predetermined amount, the air cylinder 38 is driven to drive the notch 2a.
The polishing film 1 urged by the pressure roller 41 is brought into contact with a predetermined polishing pressure.

Next, the take-up reel 39 and the pay-out reel 40 are reciprocated up and down, and the notch 2 a is polished by the polishing film 1 urged by the pressure roller 41. At this time, the boundary between the notch portion 2a and the outer peripheral portion of the disk 2 is polished by rotating the work table 37 by a required amount in the normal and reverse directions. Further, the frame body is vertically swung as necessary by a drive motor and a swing mechanism (not shown).

Next, after polishing the notch 2a, the running of the take-up reel 39 and the pay-out reel 40 and the pressing of the air cylinder 38 are stopped, and the pressure roller 41 is retracted from the polishing position.

Next, the link portion 23 is rotated by the pivot portion 21 of the transfer device 20 toward the film polishing device 30 by a predetermined amount, and further the slide portion 22 is used to rotate the link portion 23.
Is lowered by a predetermined amount. With this rotation / lowering operation, the suction pad of the link unit 23 is moved to the disk 2 on the work table 37.
Therefore, the disk 2 is sucked from above and the suction from below the work table 37 is released.

Next, after the link portion 23 is raised by a predetermined amount by the slide portion 22, the link portion 23 is rotated by the pivot portion 21 to the next process (air cleaning process) side, and is conveyed to an air cleaning device (not shown). .

In this embodiment, the polishing film 1 is run in a direction perpendicular to the disk surface. However, a processing method in which the polishing film 1 runs in a direction parallel to the disk surface may be adopted. This processing method is a known technique disclosed in JP-A-7-124853.

In the present embodiment, the description has been made according to the transport path of the disk 2. However, since the grinding device block and the film polishing device block are independent, another disk (or wafer) is At the same time, it can be controlled so that each processing is performed.

<Other Embodiments> As another embodiment, the present invention may be applied to the circumferential processing of a disk having a donut shape such as a glass disk. In particular,
The film polishing apparatus 30 of FIG. 1 is replaced by the film polishing apparatus 30 'of FIG. 5, and the outer periphery of the disk 2' having a donut shape is processed by the grinding apparatus 10 of FIG. Is polished.

In the work moving section 33 'of the film polishing apparatus 30', the slide table 35 is slidably provided in the horizontal direction (the direction of the arrow) on the pair of guide rails 34 provided on the base as described above. Have been. The work table 3 is placed on the slide table 35.
A work rotation motor 36 connected to 7 'is fixed. A hole having a diameter larger than the inner circumference of the disk 2 'is formed in the work table 37' so as to surround the inner circumference of the disk 2 '. The vacuum suction pad for suction-fixing the disk 2' from below the table as described above. (Not shown) are provided.

In the polishing section 32 ', the tape-shaped polishing film 1' is wound around a pay-out reel 40 'so as to be able to be fed out, and the fed-out polishing film 1' is applied to the pressing roller 4 '.
It is wound on a take-up reel 39 'via 1'. By controlling the above-mentioned drive motor synchronously, the polishing film 1 'reciprocates in the left-right direction,
The inner circumference of the disk 2 'positioned and fixed at 7' is pressed by the pressing roller 41 ', and the disk 2' on the work table 37 'is rotated by driving the work rotating motor 36 at a predetermined speed. The inner peripheral portion is polished with the polishing film 1 '. The width (tape width) of the polishing film 1 'is set to be smaller than the diameter of the inner peripheral portion of the disk and wider than the width of the pressure roller 41'. The polishing film 1 '
Is manufactured by the above-described method, but when processing a glass disk, cerium oxide abrasive grains or the like are used as the abrasive grains 1c that cause mechanochemical action.

The pressing unit 31 ′ is a polishing film 1 ′
A frame provided on the substrate side (back side) and rotatably supporting the pressure roller 41 ', an air cylinder 38' capable of moving the frame in the front-rear direction and the vertical direction, and a drive motor (not shown) The frame is turned left and right by driving.
A swing mechanism for swinging is provided. The pressure roller 41 'is made of an elastic material, and its outer shape, thickness, and the like are formed so as to correspond to the shape of the inner circumferential portion of the disk. The air cylinder 38 'moves the frame as described above, and urges the abrasive grain side (front side) of the polishing film 1' toward the inner peripheral portion of the disk 2 '.

In the grinding process of the inner peripheral portion of the disk, after the outer peripheral portion is ground, the disk 2 'is moved to the film polishing device 30' by the transport device 20 as described above.
The rotation center of the work table 37 'is aligned with the center of the disk 2', and the outer circumference of the pressure roller 41 'and the inner circumference of the disk are opposed to each other.

Then, in the film polishing apparatus 30 ', after the disc 2' which has been positioned is sucked and fixed from below by the suction pad of the work table 37 ', the air cylinder 38' is driven to move the frame up and down. After moving the pressing roller 41 'closer to the inner peripheral portion of the disk by moving it by a predetermined amount in the left-right direction, the polishing film 1' urged by the pressing roller 41 'is brought into contact with the inner peripheral portion at a predetermined polishing pressure. Let it.

Next, the take-up reel 39 'and the pay-out reel 40' are reciprocated right and left, and the inner periphery of the disk is polished while rotating the work table 37 'at a predetermined speed. Further, the frame body is swung in the front-rear direction as necessary by a drive motor and a swing mechanism (not shown).

Next, after the inner peripheral portion of the disk 2 'is polished, the running of the take-up reel 39' and the pay-out reel 40 ', the rotation of the work table 37', and the pressing of the air cylinder 38 'are stopped. The pressure roller 41 'is retracted.

Next, the disk 2 'after the grinding and polishing is rotated to the next step (air cleaning step) by the transfer device 20 as described above, and transferred to an air cleaning device (not shown).

According to the above-described embodiment, the disk 2,
In the finishing process of the circumferential portion of 2 ', the outer peripheral portion having a large processing area is processed by the grinding wheel 3, and the processing area is small.
The notch 2a (notch portion) having a complicated shape or the inner peripheral portion where the usable tool diameter is smaller than that of the outer peripheral portion is processed with the polishing films 1 and 1 ', thereby providing stable, high efficiency and high efficiency. Processing can be performed efficiently.

Further, according to the above-described embodiment, the abrasive grains (silica abrasive grains, barium carbonate abrasive grains, or cerium oxide abrasive grains) having a mechanochemical effect are used as the abrasive grains for the grinding wheel 3 and the polishing films 1 and 1 ′. The use of these fixed abrasive processing tools makes it possible to obtain a high-quality machined surface equivalent to conventional loose abrasive polishing.

Further, according to the above-described embodiment, by performing the grinding / polishing processing in a dry manner, the mechanochemical processing can be performed by the abrasive grains having the mechanochemical action, and at the same time, the working environment by the supply of the processing liquid can be reduced. Deterioration and increase in running cost can be suppressed.

Further, according to the above-described embodiment, mechanochemical processing can be performed, and processing marks (streaks, etc.) corresponding to the running direction of the polishing cloth or polishing film can be obtained.
Are not formed on the processed surface.

[0090]

An embodiment of the present invention will be described below.

In this embodiment, a grinding device 10 provided with the grinding wheel 3 using the above-mentioned silica abrasive, a transfer device 20 provided with a robot hand 23 having a vacuum suction pad, and a polishing film using silica abrasive Using a processing apparatus 100 composed of a film polishing apparatus 30 provided with No. 1, finishing processing of an outer peripheral portion of the 8-inch silicon wafer 2 (notched, chemical etching finish) was performed.

As the grinding wheel 3 and the polishing film 1, silica abrasive grains having a primary particle average particle diameter of 20 nm were used. As the grinding wheel 3, a resin bond grinding wheel using a phenol resin as a binder was used. Used a film having a polyethylene terephthalate film as a base material and a urethane resin as a binder.

First, after loading the silicon disk 2 into the processing apparatus 100, the silicon disk 2 is loaded into a grinding processing block by robot handling using a vacuum pad.
Here, the grinding wheel 3 is a layered grinding wheel with respect to the wafer circumferential shape, and the rotation axis of the grinding wheel is orthogonal to the wafer surface.
Then, the wafer 2 and the grinding wheel 3 are rotated at a predetermined rotation speed, and the grinding wheel 3 is cut into the outer periphery of the wafer. By this grinding step, the circumferential portion of the outer periphery of the wafer is finished to a mirror surface equivalent to free abrasive polishing.

Next, the wafer 2 is loaded into a film polishing apparatus block by robot handling using a vacuum pad. Here, the polishing film 1 runs in a direction perpendicular to the wafer surface, and processes the notch. At this time, if necessary, a swinging motion is added in a direction orthogonal to the film running direction. By this polishing step, the notch portion 2a on the outer periphery of the wafer is finished to a mirror surface equivalent to the free abrasive polishing finish.

Lastly, the finished wafer 2 is carried out of the processing apparatus after being subjected to air cleaning.

According to the present embodiment, the outer periphery of the wafer can be finished within 1 minute (the entire time from loading of the processing apparatus to unloading).
Could be completed in On the other hand, in the conventional free abrasive polishing, it took as long as 7 minutes to finish the outer periphery of the wafer as in the present embodiment.

Further, according to the present embodiment, when the mechanochemical processing using the silica abrasive grains is performed, the processing mark (stripe or the like) corresponding to the running direction of the polishing cloth or the polishing film is displayed on the processing surface of the outer peripheral portion of the wafer. No top was formed.

[0098]

As described above, according to the present invention,
In the finishing of the circumferential part of a thin disk, the outer peripheral part with a large processing area is processed with a grinding wheel, and the usable tool diameter is small, the inner peripheral part of a small diameter hole, or a notch with a small processing area and complicated shape. By processing the part with a polishing film, processing can be performed stably, with high efficiency and high efficiency.

Further, by using abrasive grains that generate a mechanochemical action as the abrasive grains used for the grinding wheel and the polishing film, even if these fixed abrasive processing tools are used, the same abrasive grain as the conventional free abrasive polishing is used. A high quality processed surface can be obtained.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a schematic configuration of a processing apparatus according to an embodiment of the present invention.

FIG. 2 is a diagram showing a shape of a grinding wheel in one embodiment of the present invention.

FIG. 3 is a diagram showing a disk (or wafer) to be processed according to an embodiment of the present invention.

FIG. 4 is a diagram showing a cross section of a polishing film according to one embodiment of the present invention.

FIG. 5 is a diagram showing a schematic configuration of a film polishing apparatus according to another embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1, 1 'Polishing film 1a Base material (resin film) 1b Binder resin 1c Abrasive grains 2, 2' Disk (or wafer) 2a Notch part (notch part) 3 Grinding grindstone 3a-3c Groove 10 Grinding device 11, 33 Work moving part 12 Grinding part 20 Conveying device 21 Pivot part 22 Slider part 23 Link part 30, 30 'Film polishing device 31, 31' Pressure unit 32, 32 'Polishing unit

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Toshiyuki Enomoto 1-3-6 Nakamagome, Ota-ku, Tokyo Inside Ricoh Co., Ltd. (72) Inventor Yasuhiro Tani 3-47-12, Miyasaka 3-47-12, Setagaya-ku, Tokyo (72 ) Inventor Shigeru Inoue 4029 Nakatsu, Aikawa-cho, Aiko-gun, Kanagawa F-term (reference) 3C049 AA02 AA03 AA13 AA16 AA18 AB03 AB06 BB06 CA01 CA06 CB01 CB03

Claims (8)

[Claims] 1. A method for finishing a peripheral portion of a thin-walled disk, comprising: a grinding step of processing an outer peripheral portion of the thin-walled disk with a grinding wheel; and a polishing film for forming a notch or an inner peripheral portion on the outer periphery of the thin-walled disk. And a polishing step of processing by a method according to claim 1, further comprising: 2. The method according to claim 1, wherein in the grinding step, a grinding wheel using abrasive grains that produces a mechanochemical action is used. 3. The method according to claim 1, wherein in the polishing step, a polishing film using abrasive grains that generates a mechanochemical action is used. 4. The method for circumferentially working a thin disk according to claim 2, wherein an average primary particle diameter of the abrasive grains producing the mechanochemical action is 0.8 nm to 10 μm. 5. A method according to claim 1, wherein said grinding step and said polishing step are performed in a dry manner. 6. A processing device for finishing a peripheral portion of a thin-walled disk, comprising: a grinding device for processing an outer peripheral portion of the thin-walled disk with a grinding wheel; and a notch or an inner peripheral portion on an outer periphery of the thin-walled disk. A polishing apparatus for processing a thin disk with a polishing film, and a transfer device for moving the thin disk between the grinding apparatus and the film polishing apparatus, and positioning and fixing the thin disk. apparatus. 7. The processing apparatus according to claim 6, wherein said grinding wheel and said polishing film are made of abrasive grains which produce a mechanochemical action. 8. The processing apparatus according to claim 7, wherein the average primary particle diameter of the abrasive grains producing the mechanochemical action is 0.8 nm to 10 μm.