Chemical grinding and polishing system

Abstract

A chemical grinding and polishing system includes a base unit, a grinding unit, a moving unit, a dressing unit, and a working unit. The grinding unit includes a turntable and a grinding pad disposed on the turntable. The dressing unit includes an adjustment table disposed on the moving unit, a dressing module disposed on the adjustment table, and a dressing wheel disposed on the dressing module. The dressing wheel has a dressing surface and a dressing ring surface connected to the dressing surface. The dressing module and the dressing wheel can be adjusted between a first state and a second state. In the first state, the dressing module and the dressing wheel are adjusted so that the dressing surface faces the grinding pad. In the second state, the dressing module and the dressing wheel are adjusted so that the dressing ring surface faces the grinding pad, thereby grinding the grinding pad to improve processing accuracy.

Description

[Technical Field]

[0001] This invention relates to a grinding apparatus, and more particularly to a chemical grinding and polishing system. [Previous Technology]

[0002] An existing chemical mechanical polishing system includes a rotatable base, a polishing pad disposed on the base and rotatable by the base, and a positioning and rotating device located above the polishing pad for fixing a workpiece to be polished. In use, the positioning and rotating device moves the workpiece to be polished onto the polishing pad for polishing, thereby achieving the effect of polishing the workpiece. When the polishing pad needs to be adjusted, a diamond disc is installed on the positioning and rotating device, and the polishing pad is polished through the diamond disc. However, repeatedly disassembling and installing the diamond disc is rather cumbersome.

[0003] Therefore, another existing chemical mechanical polishing system, as shown in Republic of China Patent No. TW202426180A, includes a rotatable base, a polishing pad disposed on the base and rotatable by the base, a positioning and rotating device located above the polishing pad for fixing a workpiece to be polished, and a diamond disc disposed above the polishing pad. In use, the positioning and rotating device moves the workpiece to be polished onto the polishing pad for polishing, and the diamond disc removes the debris generated after polishing that falls onto the polishing pad, thereby achieving the effect of polishing the workpiece.

[0004] However, when the grinding pad is first used, or when the surface of the base is uneven, it needs to be pre-treated to improve tolerance issues. The diamond disc is used to grind debris and is not suitable for treating the grinding pad or the base, so it is necessary to make improvements. [Summary of the Invention]

[0005] Therefore, the object of the present invention is to provide a chemical grinding and polishing system that overcomes the disadvantages of the prior art.

[0006] Therefore, the present invention provides a chemical grinding and polishing system for grinding and polishing a wafer. The chemical grinding and polishing system includes a base unit, a grinding unit, a moving unit, a trimming unit, and a working unit.

[0007] The grinding unit includes a turntable disposed on the base unit and rotatable about a first axis, and a grinding pad disposed on the turntable. The first axis extends in a vertical direction. The moving unit includes a horizontal moving module disposed on the base unit, a rotating module disposed on the horizontal moving module and rotatable about a first direction perpendicular to the vertical direction by the horizontal moving module, and a vertical moving module disposed on the rotating module and rotatable about a second axis by the rotating module.

[0008] The trimming unit includes an adjustment platform disposed on the up-down moving module and movable along the up-down direction by the up-down moving module, a trimming module disposed on the adjustment platform in an adjustable state, and a trimming wheel disposed on the trimming module and rotatable around a third axis by the trimming module. The trimming wheel can be used to trim the polishing pad and has a trimming surface opposite to the trimming module and a trimming ring surface connected to the trimming surface and surrounding the third axis. The trimming module and the trimming wheel can be adjusted between a first state and a second state. In the first state, the trimming module and the trimming wheel are adjusted to a state in which the trimming surface faces the polishing pad. In the second state, the trimming module and the trimming wheel are adjusted to a state in which the trimming ring surface faces the polishing pad.

[0009] The working unit is disposed on the base unit. The working unit includes a tray assembly that can be driven to move along the vertical direction and is used for placing the wafer. The tray assembly can be driven to make the wafer contact the polishing pad and be polished.

[0010] The advantage of the present invention is that by setting the dressing module and the dressing wheel that can adjust the first state and the second state, the grinding pad can be ground before and during processing, and the turntable can be ground before processing, thereby improving the processing accuracy.

Implementation Method

[0011] Referring to Figures 1 and 2, an embodiment of the chemical grinding and polishing system of the present invention is used to grind and polish three wafers 9. The chemical grinding and polishing system includes a base unit 2, a grinding unit 3, a moving unit 4, a dressing unit 5, and three working units 6.

[0012] The grinding unit 3 includes a turntable 31 disposed on the base unit 2 and rotatable about a first axis L1, and a grinding pad 32 disposed on the turntable 31. The first axis L1 extends in a vertical direction Z. In this embodiment, the turntable 31 is made of stainless steel, and the grinding pad 32 is a soft grinding pad, but in other embodiments, the grinding pad 32 may also be a hard grinding pad.

[0013] The moving unit 4 includes a horizontal moving module 41 disposed on the base unit 2, a rotating module 42 disposed on the horizontal moving module 41 and capable of being driven by the horizontal moving module 41 to move along a first direction X perpendicular to the vertical direction Z, and a vertical moving module 43 disposed on the rotating module 42 and capable of being driven by the rotating module 42 to rotate around a second axis L2.

[0014] The trimming unit 5 includes an adjustment platform 51 disposed on the up-down moving module 43 and movable along the up-down direction Z by the up-down moving module 43, a trimming module 52 disposed on the adjustment platform 51 in an adjustable state, and a trimming wheel 53 disposed on the trimming module 52 and movable about a third axis L3 by the trimming module 52.

[0015] In this embodiment, the horizontal moving module 41, the rotating module 42 and the vertical moving module 43 are composed of lead screws, nuts and other common platform components. Since these are common technical means in the field and are not the focus of this case, the detailed components will not be further described.

[0016] Referring to Figures 1, 3 and 4, the adjustment platform 51 has four first screw holes 511 and four second screw holes 512. In this embodiment, in order to save space, one of the first screw holes 511 and one of the second screw holes 512 are the same hole, but this is not a limitation.

[0017] The trimming module 52 has a trimming base 521, a trimming motor 522 disposed on the trimming base 521 and used to drive the trimming wheel 53, four mounting holes 523 located on the trimming base 521, and four mounting screws 524.

[0018] The dressing wheel 53 can be used to dress the grinding pad 32, and has a dressing surface 531 opposite to the dressing module 52, and a dressing ring surface 532 connected to the dressing surface 531 and surrounding the third axis L3. In this embodiment, the dressing surface 531 is made of the same material as the diamond disc, and the dressing ring surface 532 is made of the same material as the grinding wheel.

[0019] The trimming module 52 and the trimming wheel 53 can be adjusted between a first state and a second state. In the first state (refer to FIG. 3), the trimming module 52 and the trimming wheel 53 are adjusted to such that the trimming surface 531 faces the polishing pad 32, and the mounting screws 524 are respectively inserted into the mounting holes 523 and screwed into the first screw holes 511. In the second state (refer to FIG. 4), the trimming module 52 and the trimming wheel 53 are adjusted to such that the trimming ring surface 532 faces the polishing pad 32, and the mounting screws 524 are respectively inserted into the mounting holes 523 and screwed into the second screw holes 512.

[0020] Referring to Figures 1, 5 and 6, for ease of explanation, the following description uses one of the working units 6 and a corresponding wafer 9. The working unit 6 is disposed on the base unit 2. The working unit 6 includes a first moving module 61 disposed on the base unit 2, a mounting tube 62 disposed on the first moving module 61 and movable along a second direction Y perpendicular to the vertical direction Z by the first moving module 61, a second moving module 63 passing through the mounting tube 62, a connecting module 64 passing through the mounting tube 62, and a tray group 65 that can be moved along the vertical direction Z by the first moving module 61 and is used for placing the wafer 9.

[0021] In this embodiment, the first moving module 61 is composed of a lead screw, a nut, and other common platform components. Since these are common technical means in the field and not the focus of this case, the detailed components will not be further described. The second moving module 63 is a retractable pressure cylinder.

[0022] The connecting module 64 has a first connector 641 connecting the second moving module 63, a second connector 642 passing through the mounting tube 62, a plurality of elastic members 643 abutting the second connector 642 downward, and a ball bearing 644 surrounding the first connector 641 and the second connector 642 to allow the second connector 642 to deflect relative to the first connector 641.

[0023] The second connector 642 has an outer tube wall 645, an inner annular wall 646 extending inward from the outer tube wall 645, a thrust ring seat 647 disposed on the inner annular wall 646, and a through hole 648 defined by the thrust ring seat 647. The elastic elements 643 are disposed on the thrust ring seat 647.

[0024] The bearing assembly 65 is disposed on the connecting module 64 and can be moved along the vertical direction Z by the connecting module 64. The bearing assembly 65 can be driven by the connecting module 64 to make the wafer 9 contact the polishing pad 32 for polishing. The bearing assembly 65 has a disc body 651, a rod body 652 extending upward from the disc body 651 and passing through the second connecting member 642, a thrust bearing seat 653 surrounding the rod body 652 and pressing downward against the elastic member 643 to constantly bear the upward elastic force of the elastic member 643, an adjusting nut 654 screwed to one end of the rod body 652 opposite to the disc body 651 and located above the thrust bearing seat 653, and a thrust bearing ring 655 disposed between the thrust bearing seat 653 and the adjusting nut 654. In this embodiment, the thrust bearing seat 653 and the thrust bearing ring 655 are fitted together with inclined surfaces. The two and the elastic members 643 can produce a buffering effect. Adjusting the position of the adjusting nut 654 can drive the thrust bearing ring 655 and the thrust bearing seat 653 to press against and change the preload of the elastic member 643.

[0025] The rod body 652 has a large diameter section 656 that connects to the disc body 651 and has an outer diameter larger than the diameter of the through hole 648, and a small diameter section 657 that passes through the through hole 648 from the large diameter section 656 and is screwed into the adjusting nut 654.

[0026] Referring to Figures 1, 4 and 7, before processing, the dressing module 52 and the dressing wheel 53 are adjusted to the second state, and the moving unit 4 is controlled to drive the dressing ring surface 532 of the dressing wheel 53 to approach the grinding pad 32. Then, by driving the grinding unit 3 to rotate, the grinding pad 32 can be ground before use. Alternatively, the grinding pad 32 can be removed first, and the surface of the turntable 31 can be ground to correct the tolerance, thereby improving the processing accuracy.

[0027] Referring to Figures 1, 3 and 8, when the wafer 9 is to be polished, the trimming module 52 and the trimming wheel 53 are first adjusted to the first state, and the moving unit 4 is controlled to drive the trimming surface 531 of the trimming wheel 53 to approach the polishing pad 32. Then, by driving the polishing unit 3 to rotate, the polishing pad 32 can be polished in use.

[0028] Referring to Figures 1, 5 and 6, by driving the first moving module 61 to move the bearing plate 65 above the polishing pad 32, the second moving module 63 drives the connecting module 64 and the bearing plate 65 to move downwards until the wafer 9 contacts the polishing pad 32, so that the wafer 9 can be polished. The dust and debris generated during the polishing process are accumulated on the polishing pad 32 and are simultaneously polished by the dressing wheel 53 and removed, thereby completing the polishing and polishing operation of the wafer 9.

[0029] At the instant the wafer 9 is driven to contact the polishing pad 32, due to the arrangement of the ball bearing 644, the second connector 642 can be deflected relative to the first connector 641, thereby maintaining a stable contact between the surface of the wafer 9 and the polishing pad 32. The elastic elements 643 provide cushioning for the wafer 9's contact with the polishing pad 32, preventing damage to the wafer 9 due to excessive force during contact. Adjusting the adjusting nut 654 can change the elasticity of the elastic elements 643, thereby changing the degree of deflection of the bearing assembly 65 under force, achieving the effect of changing the swing freedom of the bearing assembly 65.

[0030] It should be noted that the dressing wheel 53 can be made of different materials in the first state and the second state. For example, in the first state, the dressing wheel 53 is a diamond disc, and in the second state (see Figure 9), the dressing wheel 53 is a grinding wheel.

[0031] In addition, in this embodiment, the trimming module 52 and the adjustment platform 51 are connected by the mounting screws 524 (see Figures 3 and 4). However, in other embodiments, referring to Figures 10 and 11, a turntable 54 can be provided between the trimming module 52 and the adjustment platform 51. By rotating the turntable 54, the state of the trimming module 52 and the trimming wheel 53 can be changed.

[0032] In summary, by setting the dressing module 52 and the dressing wheel 53 which can adjust the first state and the second state, the grinding pad 32 can be ground before and during processing, and the turntable 31 can be ground before processing, thereby improving the processing accuracy. Therefore, the purpose of the present invention can be achieved.

[0033] However, the above description is only an embodiment of the present invention and should not be construed as limiting the scope of the present invention. Any simple equivalent changes and modifications made in accordance with the scope of the patent application and the contents of the patent specification of the present invention shall still fall within the scope of the patent of the present invention. [Simplified Explanation of the Diagram]

[0034] Other features and effects of the present invention will be clearly presented in the embodiments with reference to the drawings, wherein: FIG1 is a perspective view of an embodiment of the chemical grinding and polishing system of the present invention; FIG2 is a front view of the embodiment; FIG3 is an exploded perspective view of a dressing unit of the embodiment, illustrating a dressing module and a dressing wheel in a first state; FIG4 is a view similar to FIG3, illustrating the dressing module and the dressing wheel in a second state; FIG5 is an incomplete exploded perspective view of a working unit of the embodiment; FIG6 is a cross-sectional view of a connecting module and a bearing assembly of the embodiment; FIG7 is a usage state diagram, illustrating the working unit shortened, and the dressing module and the dressing wheel in the second state; FIG8 is a view similar to FIG7, illustrating the working unit extended, and the dressing module and the dressing wheel in the first state; FIG9 is a view similar to FIG7, illustrating the state of the dressing wheel as a grinding wheel. Figure 10 is an incomplete perspective view of another embodiment of the chemical grinding and polishing system of the present invention, illustrating a turntable disposed between a dressing module and an adjustment table, and the dressing module and a dressing wheel being in a first state; and Figure 11 is a view similar to Figure 10, illustrating the dressing module and the dressing wheel being in a second state.

Claims

1. A chemical polishing and grinding system for polishing a wafer, the chemical polishing and grinding system comprising: a base unit; a polishing unit including a turntable disposed on the base unit and rotatable about a first axis, and a polishing pad disposed on the turntable, the first axis extending in a vertical direction; and a moving unit including a horizontal moving module disposed on the base unit, a rotating module disposed on the horizontal moving module and rotatable about a first direction perpendicular to the vertical direction, and a vertical moving module disposed on the rotating module and rotatable about a second axis. A dressing unit includes an adjustment platform disposed on the vertically movable module and movable along the vertical direction by the vertically movable module, a dressing module disposed on the adjustment platform in an adjustable state, and a dressing wheel disposed on the dressing module and rotatable about a third axis by the dressing module. The dressing wheel is used to dress the polishing pad and has a dressing surface opposite to the dressing module, and a dressing ring surface connected to the dressing surface and surrounding the third axis. The dressing module and the dressing wheel are rotatable in a... The adjustment is between a first state and a second state. In the first state, the trimming module and the trimming wheel are adjusted to position the trimming surface facing the polishing pad. In the second state, the trimming module and the trimming wheel are adjusted to position the trimming ring surface facing the polishing pad. A working unit is disposed on the base unit. The working unit includes a support plate assembly that can be driven to move along the vertical direction and is used for placing the wafer. The support plate assembly can be driven to make the wafer contact the polishing pad and be polished.

2. The chemical grinding and polishing system as described in claim 1, wherein, The adjustment platform has a plurality of first screw holes and a plurality of second screw holes. The dressing module has a dressing base, a dressing motor disposed on the dressing base and used to drive the dressing wheel, a plurality of mounting holes located on the dressing base, and a plurality of mounting screws. In the first state, the dressing module and the dressing wheel are respectively inserted into the mounting holes and screwed into the first screw holes, so that the dressing surface faces the polishing pad. In the second state, the dressing module and the dressing wheel are respectively inserted into the mounting holes and screwed into the second screw holes, so that the dressing ring surface faces the polishing pad.

3. The chemical grinding and polishing system as described in claim 2, wherein, The working unit also includes a first moving module disposed on the base unit, an installation tube disposed on the first moving module and movable along a second direction perpendicular to the vertical direction by being driven by the first moving module, a second moving module passing through the installation tube, and a connecting module passing through the installation tube. The bearing plate assembly is disposed on the connecting module and can be moved along the vertical direction by being driven by the connecting module.

4. The chemical grinding and polishing system as described in claim 3, wherein, The connecting module has a first connector for connecting the second moving module, a second connector for passing through the mounting tube, and a plurality of elastic members that abut downward against the second connector. The bearing assembly has a disc body, a rod extending upward from the disc body and passing through the second connector, a thrust bearing seat surrounding the rod body and abutting downward against the elastic member to constantly bear the upward elastic force of the elastic member, an adjusting nut screwed to one end of the rod body opposite to the disc body and located above the thrust bearing seat, and a thrust bearing ring disposed between the thrust bearing seat and the adjusting nut.

5. The chemical grinding and polishing system as described in claim 4, wherein, The connection module also has a spherical bearing surrounding the first connector and the second connector to allow the second connector to deflect relative to the first connector.

6. The chemical grinding and polishing system as described in claim 5, wherein, The second connector has an outer tube wall, an inner ring wall extending inward from the outer tube wall, a thrust ring seat disposed on the inner ring wall, and a through hole defined by the thrust ring seat. The elastic elements are disposed on the thrust ring seat. The rod has a large-diameter section that connects to the disc and has an outer diameter larger than the diameter of the through hole, and a small-diameter section that passes through the through hole from the large-diameter section and is screwed on by the adjusting nut.

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