CN115592565B

CN115592565B - Device and method for dressing a grinding wheel

Info

Publication number: CN115592565B
Application number: CN202211284175.0A
Authority: CN
Inventors: 贺云鹏; 王贺
Original assignee: Xian Eswin Material Technology Co Ltd
Current assignee: Xian Eswin Material Technology Co Ltd
Priority date: 2022-10-14
Filing date: 2022-10-14
Publication date: 2025-03-14
Anticipated expiration: 2042-10-14
Also published as: CN115592565A; TW202332538A; TWI848489B

Abstract

An embodiment of the invention discloses a device for dressing a grinding wheel, which comprises a columnar dressing part, a distance sensor and a distance sensor, wherein the columnar dressing part can rotate around a central axis of the dressing part to dress grinding teeth of the grinding wheel through a circumferential surface of the dressing part, the distance sensor is used for sensing a feeding distance of the grinding wheel relative to the circumferential surface of the dressing part, and when the distance sensor senses that the feeding distance of the grinding wheel relative to the circumferential surface of the dressing part reaches a first preset distance, the dressing operation is ended.

Description

Device and method for dressing grinding wheel

Technical Field

The invention relates to the technical field of semiconductor manufacturing, in particular to a device and a method for dressing a grinding wheel.

Background

The production process of semiconductor silicon wafers generally includes crystal pulling, wire cutting, grinding, polishing, and the like. Double-sided lapping is used as a lapping process for simultaneously lapping both main surfaces of a silicon wafer to give the silicon wafer a highly flat surface. During double-sided lapping, a special device is required to hold the wafer so that the lapping wheel grinds both major surfaces of the wafer simultaneously. Typically, such holding means comprise a pair of hydrostatic plates disposed in opposition, the wafer being disposed vertically between the two hydrostatic plates, the hydrostatic plates being capable of forming a fluid barrier between themselves and the major surfaces of the wafer so as to enable the wafer to be held upright without contact with the two hydrostatic plates, while at the same time the two major surfaces of the wafer can be lapped using opposing lapping wheels. Compared with physical clamping, the fluid clamping mode of the fluid static plate reduces damage to the silicon wafer and enables the silicon wafer to move (rotate) tangentially relative to the surface of the fluid static plate with less friction.

During the above-described grinding process, the quality of the grinding wheel is critical to the grinding quality. With continuous processing of the equipment, grinding wheels, particularly grinding teeth on the left and right sides are continuously worn, the worn grinding teeth may not be flat on the whole, the roughness of the grinding teeth themselves may not meet the process requirements, and these factors eventually lead to the degradation of the precision of processing silicon wafers. Therefore, the periodic dressing of the grinding wheel has a significant impact on the grinding process and the quality of the wafer. The grinding wheel needs to be dressed regularly, and the currently adopted method is that the circumferential edge of the disc-shaped dressing machine is aligned with the grinding surface of the grinding teeth, and the grinding wheel is manually fed towards the dressing machine by an operator to drew the grinding surface of the grinding wheel by the dressing machine under the condition that the dressing machine and the grinding wheel rotate simultaneously.

However, how to accurately control the dressing amount of the dresser to the grinding wheel so that the dressed grinding wheel meets the predetermined requirements and so that a plurality of dressed grinding wheels have better consistency is a problem in the art.

Disclosure of Invention

In view of the foregoing, it is desirable to provide an apparatus and a method for dressing a grinding wheel to control a dressing operation progress according to a feeding amount of the grinding wheel relative to the dressing apparatus, thereby accurately controlling a dressing amount of the grinding wheel, enabling the dressed grinding wheel to meet a predetermined requirement and enabling a plurality of dressed grinding wheels to have a good consistency.

The technical scheme of the invention is realized as follows:

in a first aspect, embodiments of the present invention provide an apparatus for dressing a grinding wheel, the apparatus comprising:

a columnar dressing portion provided rotatably about a central axis thereof to dress a grinding tooth of a grinding wheel by a circumferential surface of the dressing portion;

A distance sensor for sensing a feeding distance of the grinding wheel relative to the circumferential surface of the dressing portion;

wherein when the distance sensor senses that a feeding distance of the grinding wheel with respect to the circumferential surface of the dressing portion reaches a first predetermined distance, the dressing operation is ended.

In a second aspect, embodiments of the present invention provide a method for dressing a grinding wheel, the method being performed using an apparatus according to the first aspect.

The embodiment of the invention provides a device and a method for dressing a grinding wheel, wherein the device comprises a distance sensor for sensing the feeding distance of the grinding wheel relative to the circumferential surface of a dressing part, and the grinding wheel is continuously fed to the dressing part in the dressing process, and the feeding distance of the grinding wheel can characterize the dressing amount of the dressing part on the grinding wheel, so that the actual dressing amount of the grinding wheel can be controlled to be consistent with the target dressing amount by controlling the actual feeding distance of the grinding wheel, thereby not only avoiding the condition of insufficient dressing amount or excessive dressing of single grinding wheel, but also being beneficial to controlling the consistency of a plurality of dressed grinding wheels in batch dressing, thereby achieving the aim of controlling the quality consistency of the grinded silicon wafers.

Drawings

FIG. 1 is a schematic view of a conventional apparatus for dressing a grinding wheel;

FIG. 2 is a schematic view of an apparatus for dressing a grinding wheel according to an embodiment of the present invention;

FIG. 3 is a schematic view of an apparatus for dressing a grinding wheel according to another embodiment of the present invention;

FIG. 4 is a schematic view of an apparatus for dressing a grinding wheel according to yet another embodiment of the present invention;

fig. 5 is a schematic view of an apparatus for dressing a grinding wheel according to still another embodiment of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention.

Referring to fig. 1, which shows one embodiment of a conventional dressing apparatus 1 for dressing a grinding wheel W, the dressing apparatus 1 includes a dressing portion 2 having a substantially disk shape and a support shaft 3 supporting the dressing portion 2 from below and capable of driving the dressing portion 2 to rotate about its own rotation axis, wherein the dressing apparatus dresses grinding teeth T of the grinding wheel W through its circumferential surface while rotating about its own central axis.

Currently, when dressing the grinding wheel using this dressing apparatus 1, first, the grinding teeth T of the grinding wheel W are manually controlled by an operator to align with the circumferential surface of the dressing section 2 based on visual observation, after which, in the case of the dressing apparatus rotating, the operator manually moves the grinding wheel W toward the dressing apparatus 1 to dress the grinding teeth T of the grinding wheel W by the circumferential surface of the dressing section 2, in which process the dressing amount of the grinding wheel is determined by the operator through visual observation in combination with operation experience, it is difficult to control the dressing amount of the grinding wheel to exactly the predetermined dressing amount, and therefore, when a plurality of grinding wheels need to be dressed, it is basically impossible to ensure the sizes of the dressed plurality of grinding wheels such as tooth heights and roughness uniformity of the grinding teeth, and if silicon wafers are produced using those grinding wheels with poor uniformity, the roughness of the obtained silicon wafers hardly reaches uniformity.

In order to solve the above-described problems, referring to fig. 2, an embodiment of the present invention proposes an apparatus 100 for dressing a grinding wheel, the apparatus 100 comprising a cylindrical dressing portion 101, the dressing portion 101 being provided to be rotatable about a central axis X thereof to dress grinding teeth T of a grinding wheel W by a circumferential surface 1011 of the dressing portion 101, a distance sensor 102 for sensing a feeding distance of the grinding wheel W with respect to the circumferential surface 1011 of the dressing portion 101, wherein when the distance sensor 102 senses that the feeding distance of the grinding wheel W with respect to the circumferential surface 1011 of the dressing portion 101 reaches a first predetermined distance, a dressing operation is ended. The following is a specific description with the example shown in fig. 2.

As shown in fig. 2, the apparatus 100 includes a dressing portion 101 and a distance sensor 102, and when the apparatus 100 is used to dress the grinding wheel W, the tip of the grinding tooth T of the grinding wheel W is aligned toward the circumferential surface 1011 of the apparatus 100 and is moved toward the apparatus 100, and during the movement, the distance sensor 102 always senses the feeding distance of the grinding wheel W relative to the apparatus 100, and in the example shown in fig. 2, the distance sensor 102 is provided to sense the distance between the surface of the grinding wheel W provided with the grinding tooth T and the circumferential surface 1011 of the dressing portion 101, that is, the feeding distance D1 of the grinding wheel W, and when the grinding wheel W is moved to be in contact with the circumferential surface 1011 of the apparatus 100, the apparatus 100 finishes the dressing of the grinding tooth T from the tip of the grinding tooth T via the circumferential surface 1011 by rotating around the central axis X, and once the feeding distance D1 of the distance sensor 102 reaches a predetermined distance, it should be explained that the predetermined distance corresponds to the amount to be dressed of the grinding tooth, and that the amount to be drew is required to be dressed, and the accuracy of the grinding wheel to be dressed is determined according to the actual conditions, such as the actual conditions of the grinding and the mass-production. Therefore, performing the dressing operation based on the feeding distance D1 can accurately achieve the target dressing amount, so that the dressed grinding wheel can meet the predetermined requirements.

The embodiment of the present invention provides an apparatus 100 for dressing a grinding wheel, the apparatus 100 including a distance sensor 102 sensing a feeding distance of the grinding wheel W with respect to the circumferential surface 1011 of the dressing part 101, since the grinding wheel W is continuously fed to the dressing part 101 during dressing and the feeding distance of the grinding wheel can characterize a dressing amount of the grinding wheel W by the dressing part 101, based on which an actual dressing amount of the grinding wheel W can be controlled to coincide with a target dressing amount by controlling the actual feeding distance of the grinding wheel, not only can cases of insufficient or excessive dressing of a single grinding wheel be avoided, but also it is advantageous to control uniformity of a plurality of dressed grinding wheels at the time of batch dressing, thereby achieving the purpose of controlling quality uniformity of a silicon wafer to be polished.

According to a preferred embodiment of the present invention, referring to fig. 3, the apparatus 100 further comprises a controller 103 in communication with the distance sensor 102, the controller 103 being arranged to stop the dressing 101 from rotating when the distance sensor 102 senses that the feeding distance D1 reaches the first predetermined distance, thereby ending the dressing operation.

In order to increase the cost efficiency, the dressing part 101 may be rotated only when it comes into contact with the grinding wheel W, or in order to ensure the stability of the start stage of the dressing operation, to avoid damage to the grinding teeth caused by abrupt start of the dressing part 101, or the dressing part 101 may be rotated when the grinding wheel W approaches, based on which, preferably, the controller 103 is configured to start rotation of the dressing part 101 when the distance sensor 102 senses that the feeding distance D1 reaches a second predetermined distance, which may be determined according to actual production requirements.

In order to enable the dressing portion 101 to dress the grinding wheel through the entire circumferential surface 1011 thereof, it is preferable that the dressing portion 101 is provided so as to be capable of reciprocating along the central axis while rotating about the central axis, whereby the range in which each grinding tooth contacts the circumferential surface 1011 can be enlarged, instead of dressing the grinding wheel always in a fixed partial area, thereby improving dressing uniformity and dressing efficiency.

According to another preferred embodiment of the present invention, the dressing 101 has a length along the central axis that is greater than the diameter of the grinding wheel, so that the grinding wheel can be dressed over a larger area.

In order to enable the dressing portion 101 to be stably supported and in order to enable chips generated in a dressing operation to leave the dressing device and the grinding wheel as soon as possible to avoid interfering with the subsequent dressing operation, it is preferable that, referring to fig. 4, the device 100 is arranged such that the central axis X of the dressing portion 101 is in a vertical direction, and the device 100 further includes a base 104 provided below the dressing portion 101 along the central axis X, the base 104 having a shape protruding upward along the central axis X so that substances falling on the base 104 leave the base along a surface of a top of the base 104, thereby avoiding accumulation of such chips on the dressing portion 101 to affect the dressing effect, and also avoiding contamination of the grinding wheel by the chips.

Since the frictional interaction of the dressing 101 with the grinding teeth T during dressing generates a large amount of heat which not only affects the dressing effect but also may accelerate the wear of the dressing and grinding teeth, in order to reduce the influence of heat on the apparatus 1 and the grinding wheel W, it is preferable that the apparatus 100 further includes an ejector 105 for ejecting the coolant to the dressing 101 and the grinding wheel W when the dressing 101 performs the dressing operation, as seen in fig. 5.

By way of illustrative, but non-limiting example, the conditioning portion is made of diamond and ceramic binder.

Embodiments of the present invention provide a method for dressing a grinding wheel, which is performed by using the above-described apparatus.

The technical schemes described in the embodiments of the present invention may be arbitrarily combined without any conflict.

The foregoing is merely illustrative of the present invention, and the present invention is not limited thereto, and any person skilled in the art will readily recognize that variations or substitutions are within the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. A device for dressing a grinding wheel, characterized in that the device comprises:

A cylindrical dressing portion, the dressing portion being arranged to be rotatable about its own central axis so as to dress the grinding teeth of the grinding wheel through the circumferential surface of the dressing portion;

a distance sensor, the distance sensor being used to sense a feed distance of the grinding wheel relative to the circumferential surface of the dressing portion, the feed distance being used to characterize a dressing amount of the grinding wheel by the dressing portion;

When the distance sensor senses that the feeding distance of the grinding wheel relative to the circumferential surface of the dressing portion reaches a first predetermined distance, the dressing operation ends.

2 . The device according to claim 1 , further comprising a controller in communication with the distance sensor, wherein the controller is configured to stop the trimming part from rotating when the distance sensor senses that the feeding distance reaches the first predetermined distance.

3 . The device according to claim 2 , wherein the controller is configured to enable the trimming part to start rotating when the distance sensor senses that the feeding distance reaches a second predetermined distance.

4 . The device according to claim 1 , wherein the trimming portion is configured to be capable of reciprocating along the central axis while rotating about the central axis.

5 . The device according to claim 4 , wherein a length of the dressing portion along the central axis is greater than a diameter of the grinding wheel.

6. The device according to any one of claims 1 to 5 is characterized in that the device is arranged so that the central axis of the trimming portion is along the vertical direction, and the device also includes a base arranged below the trimming portion along the central axis, the base having a convex shape along the central axis so that the material falling on the base can leave the base along the surface of the top of the base.

7 . The device according to claim 6 , further comprising an injector for injecting coolant toward the dressing section and the grinding wheel when the dressing section performs a dressing operation.

8. The device according to any one of claims 1 to 5, characterized in that the trimming portion is made of diamond and a ceramic binder.

9. A method for dressing a grinding wheel, characterized in that the method is performed by using the device according to any one of claims 1 to 8.