US20120115403A1

US20120115403A1 - Pad conditioner head for conditioning a polishing pad

Info

Publication number: US20120115403A1
Application number: US13/384,631
Authority: US
Inventors: Xinchun Lu; Pan Shen; Yongyong He; Jianbin Luo
Original assignee: Tsinghua University
Current assignee: Tsinghua University
Priority date: 2010-06-28
Filing date: 2011-06-28
Publication date: 2012-05-10
Also published as: WO2012000426A1; CN101972988B; CN101972988A

Abstract

The pad conditioner head for conditioning a polishing pad comprises a bearing seat, a spindle, a protective cover, an annular pressure plate, a self-adaptive platen, a diamond disk and a flexible ring. A flange is mounted on the lower end of the spindle. A press ring is mounted onto a lower surface of the flange. The flexible ring has an upper edge sandwiched between the flange and the press ring and a lower edge sandwiched between the protective cover and the annular pressure plate. The flexible ring, the flange, the annular pressure plate and the self-adaptive platen define a sealed chamber (M). The protective cover, the annular pressure plate, the self-adaptive platen and the diamond disk are rotatable along with the spindle through the flexible ring and movable in an up and down direction relative to the spindle via a deformation of the flexible ring.

Description

FIELD

The present disclosure relates to chemical mechanical polishing field, and more particularly to a pad conditioner head for conditioning a polishing pad.

BACKGROUND

In a chemical mechanical polishing apparatus, after the polishing pad is used for a period of time, as the polishing pad is worn out and micro-pores in the surface of the polishing pad is filled with abrasion dust, the surface of the polishing pad may become smooth to form a glazing layer, which may reduce capabilities of the polishing pad to store and deliver for an abradant and lower both the material removing rate and the surface quality of the polishing pad. The glazing layer and is the abrasion dust on the polishing pad may be removed by properly conditioning the polishing pad by a diamond disk of a pad conditioner head, so as to increase the roughness and the service life of the polishing pad, and decrease cost and ensure the polishing uniformity. The pad conditioner head drives the diamond disk to press downwardly to contact with the polishing pad and also drives the diamond disk to rotate so that the polishing pad is conditioned while the diamond disk contacts with the polishing head and the diamond disk is rotated.
The conventional pad conditioner head for conditioning a polishing pad has a complicated structure. A chamber generating the downwardly-pressing movement and a clamp of the diamond disk are separated from each other so that the guidance of the downwardly-pressing movement and the transmission of a torque are achieved by a key joint and additional parts are needed to realize the limiting of deformation in an up and down direction.

SUMMARY

An embodiment of the present disclosure provides a pad conditioner head for conditioning a polishing pad which is simple and compact in structure and easy to manufacture and assemble.
The pad conditioner head for conditioning a polishing pad according to an embodiment of the present disclosure comprises: a bearing seat having an upper end on which a bearing end cap is mounted; a spindle rotatablely mounted in the bearing seat via a bearing, having an axial channel penetrating therethrough along an axial direction thereof, and having an upper end extended from the bearing end cap and a lower end extended from a lower end of the bearing seat, in which a seal is disposed between the lower end of the bearing seat and the spindle, a synchronous belt pulley is mounted on the upper end of the spindle, a rotating joint is mounted in an upper end of the axial channel, a flange is mounted on the lower end of the spindle, and a press ring is mounted onto a lower surface of the flange; a protective cover disposed surrounding the flange; an annular pressure plate connected with the protective cover; a self-adaptive platen having a lower end connected with the annular pressure plate and an upper end movably fitted in the axial channel, in which a connecting channel is formed in the self-adaptive platen; a diamond disk mounted onto a lower surface of the annular pressure plate; and a flexible ring having an upper edge sandwiched between the flange and the press ring and a lower edge sandwiched between the protective cover and the annular pressure plate, in which the flexible ring, the flange, the annular pressure plate and the self-adaptive platen define a sealed chamber, the protective cover, the annular pressure plate, is the self-adaptive platen and the diamond disk are rotatable along with the spindle through the flexible ring and movable in an up and down direction relative to the spindle through a deformation of the flexible ring, and the sealed chamber is communicated with the axial channel through the connecting channel.
The pad conditioner head for conditioning a polishing pad according to an embodiment of the present disclosure is simple and compact in structure, artistic in appearance, and easy to manufacture and assemble, moves stably and reliably, and has high practicality, and consequently may be widely used in a polishing apparatus.
In some embodiments, a first seal ring is disposed between the annular pressure plate and the self-adaptive platen, a second seal ring is disposed between the protective cover and the annular pressure plate, and a third seal ring is disposed between the spindle and the flange.
In one embodiment, the seal between the lower end of the bearing seat and the spindle is a labyrinth seal.
In some embodiments, a first air vent is formed in the bearing seat, a second air vent communicated with the first air vent is formed in the bearing end cap, a quick change coupler is mounted in an upper end of the second air vent, and a lower end of the first air vent is open to a space defined between the spindle and an inner bottom surface of the bearing seat such that the seal between the lower end of the bearing seat and the spindle is an air seal.
In one embodiment, the axial channel comprises an upper segment and a lower segment, in which a radial dimension of the lower segment is larger than that of the upper segment.
In one embodiment, the axial channel has a circular cross section.
In one embodiment, the upper edge and the lower edge are in the form of a flat plate and are connected with each other through a flexural transition portion.
In some embodiments, the self-adaptive platen comprises a lower platen body and an upper shaft, in which a groove is formed in a lower surface of the lower platen body, a lower end of the upper shaft is connected with an upper surface of the lower platen body and fitted into the axial channel, and the connecting channel is formed in the upper shaft.
In some embodiments, the connecting channel comprises a vertical channel portion and a lateral channel portion communicated to each other, the vertical channel portion is extended downwardly by a predetermined length from an upper end of the upper shaft, and the lateral channel portion is extended along a circumferential direction of the upper shaft so as to communicate the vertical channel portion and the sealed chamber.
In some embodiments, an upper wall of the groove has a sheet structure with a thickness of 0.1-0.5 mm.
Additional aspects and advantages of the embodiments of the present disclosure will be given in part in the following descriptions, become apparent in part from the following descriptions, or be learned from the practice of the embodiments of the present disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other aspects and advantages of the disclosure will become apparent and more readily appreciated from the following descriptions taken in conjunction with the drawings in which:

FIG. 1 is a sectional view of a pad conditioner head for conditioning a polishing pad according to an embodiment of the present disclosure;

FIG. 2 is a perspective view of a flexible ring according to an embodiment of the present disclosure;

FIG. 3 is a sectional view of a flexible ring according to an embodiment of the present disclosure;

FIG. 4 is a perspective view of a self-adaptive platen according to an embodiment of the present disclosure; and

FIG. 5 is a sectional view of a self-adaptive platen according to an embodiment of the present disclosure.

DETAILED DESCRIPTION OF EMBODIMENTS OF THE DISCLOSURE

Embodiments of the present disclosure will be described in detail in the following descriptions, examples of which are shown in the accompanying drawings, in which the same or similar elements and elements having same or similar functions are denoted by like reference numerals throughout the descriptions. The embodiments described herein with reference to the accompanying drawings are explanatory and illustrative, which are used to generally understand the present disclosure. The embodiments shall not be construed to limit the present disclosure.
In the description, relative terms such as “longitudinal”, “lateral”, “front”, “rear”, “right”, “left”, “lower”, “upper”, “horizontal”, “vertical”, “above”, “below”, “up”, “top”, “bottom” as well as derivative thereof (e.g., “horizontally”, “downwardly”, “upwardly”, etc.) should be construed to refer to the orientation as then described or as shown in the drawings under discussion. These relative terms are for convenience of description and do not require that the present disclosure be constructed or operated in a particular orientation.
In addition, terms such as “first” and “second” are used herein for purposes of description and are not intended to indicate or imply relative importance or significance.
In the description, terms concerning attachments, coupling and the like, such as “connected” and “interconnected”, refer to a relationship wherein structures are secured or attached to one another through mechanical or electrical connection, or directly or indirectly through intervening structures, unless expressly described otherwise. Specific implications of the above phraseology and terminology may be understood by those skilled in the art according to specific situations.
A pad conditioner head for conditioning a polishing pad according to an embodiment of the present disclosure will be described below with reference to the drawings.
As shown in FIGS. 1-5, the pad conditioner head for conditioning a polishing pad according to an embodiment of the present disclosure comprises a bearing seat 6, a spindle 14, a protective cover 5, an annular pressure plate 3, a self-adaptive platen 19, a diamond disk 1 and a flexible ring 18.
Particularly, the spindle 14 may be rotatablely mounted in the bearing seat 6 via a bearing 9. A bearing end cap 13 may be mounted onto an upper end of the bearing seat 6 for fixing the bearing 9 in the bearing seat 6. For instance, the spindle 14 may be axially positioned by two sets of bearings 9 to prevent the spindle 14 from sliding axially. A sleeve 8 may be disposed between the two sets of bearings 9 so that the two sets of bearings 9 may be fixed in the bearing seat 6 via the bearing end cap 13 and the sleeve 8.
As shown in FIG. 1, an axial channel 141 may be formed in the spindle 14 and penetrating therethrough along an axial direction (an up and down direction in FIG. 1) of the spindle 14. An upper end of the spindle 14 is extended out from the bearing end cap 13, a lower end of the spindle 14 is extended out from a lower end of the bearing seat 6, and a seal 20 is disposed between the lower end of the bearing seat 6 and the spindle 14. More particularly, the seal 20 is disposed between the spindle 14 and an opening formed in the lower end of the bearing seat 6 and through which the lower end of the spindle 14 is extended out so as to prevent a liquid from entering into the bearing seat 6 during the polishing process.
A synchronous belt pulley 10 is mounted onto the upper end of the spindle 14. For instance, the synchronous belt pulley 10 may be fixed to the upper end of the spindle 14 via a bolt and may be connected with a driving device (not shown, such as a driving motor) via a belt to drive the spindle 14 to rotate.
A rotating joint 11 is mounted in an upper end of the axial channel 141, so that the rotating joint 11 may be connected with a gas source (not shown) or an evacuating device (not shown, such as a vacuum pump) to supply a gas to the axial channel 141 or evacuate the axial channel 141.
A flange 15 is mounted on the lower end of the spindle 14, and a press ring 17 is mounted onto a lower surface of the flange 15. For instance, the flange 15 is fixed to a lower end surface of the spindle 14 via a bolt, and the press ring 17 is fixed to a lower end surface of the flange 15 via a bolt.
The protective cover 5 is mounted surrounding the flange 15, as shown in FIG. 1. A step is disposed in an inner chamber of the protective cover 5 connected with the annular pressure plate 3. More particularly, as shown in FIG. 1, the annular pressure plate 3 is connected on a lower end surface of the step in the inner chamber of the protective cover 5 via a pin. A lower end of the self-adaptive platen 19 is connected with the annular pressure plate 3, and an upper end of the self-adaptive platen 19 is movably fitted in the axial channel 141. A connecting channel 191 is formed in the self-adaptive platen 19 (see FIG. 5). The diamond disk 1 is mounted onto a lower surface of the annular pressure plate 3. The protective cover 5, the annular pressure plate 3, the self-adaptive platen 19 and the diamond disk 1 may be connected together via a bolt so as to cover and fix the flange 15 and the press ring 17.
The flexible ring 18 has an upper edge 181 sandwiched between the flange 15 and the press ring 17 and a lower edge 182 sandwiched between the protective cover 5 and the annular pressure plate 3. The flexible ring 18, the flange 15, the annular pressure plate 3 and the self-adaptive platen 19 define a sealed chamber M. The protective cover 5, the annular pressure plate 3, the self-adaptive platen 19 and the diamond disk 1 may be rotatable along with the spindle 14 through the flexible ring 18 and movable in the up and down direction relative to the spindle 14 through a deformation of the flexible ring 18. The sealed chamber M is communicated with the axial channel 141 through the connecting channel 191.
The pad conditioner head for conditioning a polishing pad according to an embodiment of the present disclosure is simple and compact in structure, artistic in appearance, and easy to is manufacture and assemble, moves stably and reliably, and has high practicality, and consequently may be widely used in a polishing apparatus.
In use, when the sealed chamber M is being evacuated through the rotating joint 11, the diamond disk 1, the annular pressure plate 3, the protective cover 5 and the self-adaptive platen 19 will move upwards together. When a positive pressure (generated by charging a gas into the sealed chamber M via the rotating joint 11) is applied to the sealed chamber M, the diamond disk 1, the annular pressure plate 3, the protective cover 5 and the self-adaptive platen 19 will move downwards together through the deformation of the flexible ring 18. An up and down movement of the pad conditioner head is realized by the flexible ring 18. The flexible ring 18 is extended downwards when the diamond disk 1 moves downwards, and the spindle 14 transmits a torque to the diamond disk 1 through the flexible ring 18 and rotates along with the diamond disk 1 so as to condition the polishing pad. During a process of the diamond disk 1 moving downwards to contact with the polishing pad, an elastic deformation of the self-adaptive platen 19 may be generated to enable the diamond disk 1 to have self-adaptive capability, so that the self-adaptive platen 19 may be attached onto the polishing pad in a face-to-face manner during the conditioning process and accordingly good conditioning effect may be achieved.
When the sealed chamber M is evacuated, the diamond disk 1, the annular pressure plate 3, the protective cover 5 and the self-adaptive platen 19 will move upwards together. The vacuum degree may be 0-100 kPa. A downward pressure of the pad conditioner head may vary linearly by controlling the positive pressure (the pressure of charging the sealed chamber M) when the diamond disk 1 contacts with the polishing pad. Thus, different downward pressures of the pad conditioner head may be obtained by adjusting the positive pressure according to requirements so as to satisfy requirements of different polishing pads and different conditioning process requirements of polishing pads of the same type. The downward pressure may vary from 0 to 300 Newton.
As shown in FIG. 1, in some embodiments, a first seal ring 2 may be disposed between the annular pressure plate 3 and the self-adaptive platen 19, a second seal ring 4 may be disposed between the protective cover 5 and the annular pressure plate 3, and a third seal ring 7 may be disposed between the spindle 14 and the flange 15. Thus, a sealing performance of the sealed chamber M may be enhanced, and a performance and a reliability of the pad conditioner head for conditioning a polishing pad may be improved.
As shown in FIG. 1, in one embodiment, the seal 20 between the lower end of the bearing seat 6 and the spindle 14 is an air seal. Particularly, a first air vent 61 may be formed in the bearing seat 6, and a second air vent 131 communicated with the first air vent 61 may be formed in the bearing end cap 13. A quick change coupler 12 is mounted in an upper end of the second air vent 131. A lower end of the first air vent 61 is open to a space defined between the spindle 14 and an inner bottom surface of the bearing seat 6 such that the seal 20 between the lower end of the bearing seat 6 and the spindle 14 is the air seal. It should be noted that the gas enters into a chamber of the bearing seat 6, and a part of the gas is blown out from a gap between the spindle 14 and the bearing seat 6 to form the air seal so as to prevent the liquid from entering into the chamber of the bearing seat 6 during the polishing process.
Alternatively, the seal 20 between the lower end of the bearing seat 6 and the spindle 14 may be a labyrinth seal so as to prevent the liquid from entering into the chamber of the bearing seat 6 during the polishing process.
As shown in FIG. 1, in some embodiments, the axial channel 141 comprises an upper segment 1411 and a lower segment 1412, and a radial dimension of the lower segment 1412 is larger than that of the upper segment 1411. It should be noted that the diamond disk 1 may be deformed in the up and down direction, and the self-adaptive platen 19 may be guided by the axial channel 141, thus guiding the diamond disk 1.
Particularly, when the diamond disk 1 moves upwards, a top of the self-adaptive platen 19 is pushed against a top of the lower segment 141 so as to determine an upper limit point of the upward movement of the self-adaptive platen 19. When the diamond disk 1 moves downwards, a bevel edge of the protective cover 5 is attached onto a shaft shoulder bevel edge of the flange 15 so as to determine a lower limit point of the downward movement of the self-adaptive platen 19. Therefore, a travel of the up and down movement of the diamond disk 1 may be determined. For instance, the travel of the up and down movement of the diamond disk 1 may be limited to 0-15 mm.
In one embodiment, the axial channel 141 may have a circular cross section, so that is it convenient to machine. The axial channel 141 may also have a rectangular cross section.
As shown in FIGS. 1-3, in one embodiment, the upper edge 181 and the lower edge 182 are in the form of a flat plate and are connected with each other through a flexural transition portion 183. Therefore, the upper edge 181 of the flexible ring 18 may be sandwiched between the flange 15 and the press ring 17, and the lower edge 182 of the flexible ring 18 may be sandwiched between the protective cover 5 and the annular pressure plate 3.
Referring to FIG. 1, FIG. 4 and FIG. 5, in one embodiment, the self-adaptive platen 19 comprises a lower platen body 192 and an upper shaft 193. A groove 194 is formed in a lower surface of the lower platen body 192. A lower end of the upper shaft 193 is connected with an upper surface of the lower platen body 192 and fitted into the axial channel 141. The connecting channel 191 is formed in the upper shaft 193. Thus, the rotating joint 11, the axial channel 141, the connecting channel 191 and the sealed chamber M may be communicated with each other.
Furthermore, the connecting channel 191 comprises a vertical channel part 1911 and a lateral channel part 1912 communicated to each other. The vertical channel part 1911 is extended downwardly by a predetermined length from an upper end of the upper shaft 193. The lateral channel part 1912 is extended along a circumferential direction of the upper shaft 193 so as to communicate the vertical channel part 1911 and the sealed chamber M. Thus, the sealed chamber M may be evacuated or pressurized by the rotating joint 11.
Particularly, an upper wall of the groove 194 has a sheet structure with a thickness of 0.1-0.5 mm, such as 0.3 mm, which may enable a proper elastic deformation of the self-adaptive platen 19 to be generated so as to enable the diamond disk 1 to have self-adaptive capability.
The pad conditioner head for conditioning a polishing pad according to an embodiment of the present disclosure has simple structure. The diamond disk 1 has self-adaptive capability, thus enhancing conditioning precision and efficiency of the polishing pad.
Reference throughout this specification to “an embodiment”, “some embodiments”, “one embodiment”, “an example”, “a specific examples”, or “some examples” means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the disclosure. Thus, the appearances of the phrases such as “in some embodiments”, “in one embodiment”, “in an embodiment”, “an example”, “a specific examples”, or “some examples” in various places throughout this specification are not necessarily referring to the same embodiment or example of the disclosure. Furthermore, the particular features, structures, materials, or characteristics may be combined in any suitable manner in one or more embodiments or examples.
Although explanatory embodiments have been shown and described, it would be appreciated by those skilled in the art that changes, alternatives, and modifications all falling into the scope of is the claims and their equivalents may be made in the embodiments without departing from spirit and principles of the disclosure.

Claims

1. A pad conditioner head for conditioning a polishing pad, comprising:

a bearing seat having an upper end on which a bearing end cap is mounted;

a spindle rotatably mounted in the bearing seat via a bearing, having an axial channel penetrating therethrough along an axial direction thereof, and having an upper end extended from the bearing end cap and a lower end extended from a lower end of the bearing seat, in which a seal is disposed between the lower end of the bearing seat and the spindle, a synchronous belt pulley is mounted on the upper end of the spindle, a rotating joint is mounted in an upper end of the axial channel, a flange is mounted on the lower end of the spindle, and a press ring is mounted onto a lower surface of the flange;

a protective cover disposed surrounding the flange;

an annular pressure plate connected with the protective cover;

a self-adaptive platen having a lower end connected with the annular pressure plate and an upper end movably fitted in the axial channel, in which a connecting channel is formed in the self-adaptive platen;

a diamond disk mounted onto a lower surface of the annular pressure plate; and

a flexible ring having an upper edge sandwiched between the flange and the press ring and a lower edge sandwiched between the protective cover and the annular pressure plate, in which the flexible ring, the flange, the annular pressure plate and the self-adaptive platen define a sealed chamber (M), the protective cover, the annular pressure plate, the self-adaptive platen and the diamond disk are rotatable along with the spindle through the flexible ring and movable in an up and down direction relative to the spindle through a deformation of the flexible ring, and the sealed chamber (M) is communicated with the axial channel through the connecting channel.

2. The pad conditioner head for conditioning a polishing pad according to claim 1, wherein a first seal ring is disposed between the annular pressure plate and the self-adaptive platen, a second seal ring is disposed between the protective cover and the annular pressure plate, and a third seal ring is disposed between the spindle and the flange.

3. The pad conditioner head for conditioning a polishing pad according to claim 1, wherein the seal between the lower end of the bearing seat and the spindle is a labyrinth seal.

4. The pad conditioner head for conditioning a polishing pad according to claim 1, wherein a first air vent is formed in the bearing seat, a second air vent communicated with the first air vent is formed in the bearing end cap, a quick change coupler is mounted in an upper end of the second air vent, and a lower end of the first air vent is open to a space defined between the spindle and an inner bottom surface of the bearing seat such that the seal between the lower end of the bearing seat and the spindle is an air seal.

5. The pad conditioner head for conditioning a polishing pad according to claim 1, wherein the axial channel comprises an upper segment and a lower segment, in which a radial dimension of the lower segment is larger than that of the upper segment.

6. The pad conditioner head for conditioning a polishing pad according to claim 5, wherein the axial channel has a circular cross section.

7. The pad conditioner head for conditioning a polishing pad according to claim 1, wherein the upper edge and the lower edge are in the form of a flat plate and are connected with each other through a flexural transition portion.

8. The pad conditioner head for conditioning a polishing pad according to claim 1, wherein the self-adaptive platen comprises a lower platen body and an upper shaft, in which a groove is formed in a lower surface of the lower platen body, a lower end of the upper shaft is connected with an upper surface of the lower platen body and fitted into the axial channel, and the connecting channel is formed in the upper shaft.

9. The pad conditioner head for conditioning a polishing pad according to claim 8, wherein the connecting channel comprises a vertical channel portion and a lateral channel portion communicated to each other, the vertical channel portion is extended downwardly by a predetermined length from an upper end of the upper shaft, and the lateral channel portion is extended along a circumferential direction of the upper shaft so as to communicate the vertical channel portion and the sealed chamber (M).

10. The pad conditioner head for conditioning a polishing pad according to claim 8, wherein an upper wall of the groove has a sheet structure with a thickness of 0.1-0.5 mm.