KR20040067606A - chemical mechanical polishing apparatus - Google Patents

Abstract

PURPOSE: A CMP(chemical mechanical polishing) apparatus is provided to improve work efficiency in replacing a polishing pad by reliably attaching/detaching the polishing pad to/from a platen and by eliminating the necessity of additional adhesive. CONSTITUTION: A polishing pad(32) is prepared. A platen(30) has a mounting surface on which the polysilicon pad is mounted. A vacuum absorption apparatus vacuum-absorbs and fixes the polishing pad placed on the mounting surface of the platen, including absorption holes(202), at least one vacuum line(204) and a vacuum pump(206). The absorption holes are formed on the mounting surface of the platen. The at least one vacuum line is formed inside the platen body, connected to the absorption holes. The vacuum pump provides absorption force for fixing the polishing pad to the mounting surface, connected to the at least one vacuum line.

Description

Chemical mechanical polishing apparatus

The present invention relates to a chemical mechanical polishing apparatus, and more particularly, to a chemical mechanical polishing apparatus that facilitates replacement of a polishing pad in a polishing table.

BACKGROUND OF THE INVENTION As the degree of integration of semiconductor devices manufactured on semiconductor wafers increases, multilayer wiring processes have been put to practical use. As a result, as the level of the interlayer insulating film between the multi-layer wirings increases, the planarization work for this is becoming an important issue. A chemical mechanical polishing (CMP) method is used as a manufacturing technique for planarizing the surface of a semiconductor substrate.

The CMP polishing method is a technique for mechanically and chemically polishing the surface of a wafer together with a slurry solution on a polishing pad. In general, CMP equipment attaches a polishing pad to a rotating circular flat table. While supplying an abrasive, that is, a slurry in a liquid state, to apply a slurry by rotating centrifugal force, a wafer fixed to the wafer carrier at the top of the polishing pad is placed on the surface of the polishing pad. By closely contacting and rotating, the surface of the wafer is flattened by the friction effect.

As such, in the CMP device, the polishing pad is worn through repeated wafer polishing, and when the wear limit is reached, the polishing pad is replaced with a new polishing pad, which is very difficult to replace the polishing pad of the EO.

In general, the most difficult point is that since the polishing pad is attached to the platen by an adhesive, a strong physical force is required to remove the polishing pad from the platen. Another point is that after removing the polishing pad, a cleaning operation is needed to remove the adhesive remaining on the platen surface.

Another problem is that when attaching a new polishing pad to the platen, problems such as bubble generation due to immaturity or DI inflow due to bad pad adhesive often occur. In particular, since the life of the polishing pad is very short around 20 hours, a lot of time loss occurs due to frequent replacement.

The present invention is to solve such a conventional problem, the object is to provide a new type of CMP facility that can improve the efficiency of the replacement operation of the polishing pad.

1 is a schematic diagram of a CMP apparatus having a polishing table according to a preferred embodiment of the present invention.

2 is a partial side cross-sectional view of the polishing station in the present invention;

3 is a plan view of the platen of the polishing station shown in FIG. 2;

4 and 5 are views showing an example in which the suction holes are variously arranged on the platen.

Explanation of symbols on the main parts of the drawings

25a: Polishing Station

30: platen

31: drive motor

32: polishing pad

202: suction hole

204: vacuum line

206: vacuum pump

According to a feature of the present invention for achieving the above object, a chemical mechanical polishing (CMP) facility comprises a polishing pad; A platen having a mounting surface on which the polishing pad is mounted; And a device for suction fixing the polishing pad placed on the mounting surface of the platen with a vacuum.

In this embodiment, the vacuum adsorption device includes adsorption holes formed in the mounting surface of the platen; At least one vacuum line formed in the platen body and connected to the suction holes; It may also include a vacuum pump connected to one vacuum line to provide a suction force to fix the polishing pad to the mounting surface.

In this embodiment, the mounting surface of the platen has a groove, and the suction holes are disposed on the groove. The groove may be formed in the center and the edge of the mounting surface in the circumferential direction, or may be arranged at regular intervals in the radial or circumferential direction.

For example, the embodiments of the present invention may be modified in various forms, and the scope of the present invention should not be construed as being limited by the embodiments described below. These examples are provided to more fully explain the present invention to those skilled in the art. Accordingly, the shape of the elements in the drawings and the like are exaggerated to emphasize a clearer description.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to FIGS. 1 to 4. In addition, in the drawings, the same reference numerals are denoted together for components that perform the same function.

1 is a schematic diagram of a CMP apparatus having a polishing table according to a preferred embodiment of the present invention.

Referring to FIG. 1, one or more substrates 10 are polished by a chemical mechanical polishing (CMP) device 20.

The CMP apparatus 20 according to a preferred embodiment of the present invention is largely divided into a polishing table part 110 and a multi-head rotating plate 60.

Rotatable multi-head swivel 60 is positioned on table 22. The rotary plate 60 is rotated around the rotary plate axis 64 by a rotary plate motor assembly supported by the central post 62 and located in the table 22. The center post 62 supports the rotary plate support plate 66 and the cover 68. Multi-head rotor 60 includes four carrier head systems 70a, 70b, 70c, 70d. Three of the carrier head systems receive and hold the substrate and polish the substrate by pressing the substrate against the polishing pad 32 on the platen of the polishing stations 25a, 25b, 25c.

Four carrier head systems 70a, 70b, 70c, 70d are mounted on the rotor plate support plate 66 at angles equally spaced about the rotor plate axis 64. The center post 62 causes the rotary plate motor to rotate the rotary plate support plate 66 and pivot the carrier head systems 70a, 70b, 70c, 70d and the attachment substrate around the rotary plate axis 64.

Each carrier head system 70a, 70b, 70c, 70d includes a polishing or carrier head 100. Each carrier head 100 rotates independently around its own axis and reciprocates independently laterally in a radial slot 72 formed in the rotary plate support plate 66. The carrier drive shaft 74 connects the carrier head rotating motor 76 to the carrier head 100 (shown by removal of a quarter of the cover 68). There is one carrier drive shaft and motor for each head.

The polishing table portion 110 includes a table 22, a table bottom 23 mounted thereon and a removable upper outer cover (not shown). The table bottom 23 comprises a series of polishing stations 25a, 25b, 25c.

Each polishing station 25a, 25b, 25c includes a pad conditioner device 40 and slurry supply means for supplying the slurry to the surface of the polishing pad. A slurry 50 comprising a reaction reagent (e.g., deionized water for polishing and polishing), friction particles (e.g., silicon dioxide for polishing and polishing) and a chemical reaction catalyst (e.g., potassium oxide for polishing, polishing) is a slurry of a slurry supply means. It is supplied to the surface of the polishing pad 32 by the supply pipe 52. Sufficient slurry is provided to cover and wet the entire polishing pad 32.

Referring to FIG. 2, the polishing stations 25a, 25b, 25c include a rotatable platen 30 on which the polishing pad 32 is placed. The platen 30 is rotated by the platen drive motor 31, the driving force of the drive motor 31 is transmitted to the belt pulley 31b of the platen drive shaft 31c through the belt 31a. In the best polishing process, the drive motor 31 rotates the platen 30 at about 30 to 200 revolutions per minute. Of course, lower or higher speeds can be used. In addition, the polishing pad 32 may be a composite material having a rough polishing surface. The polishing pad 32 is sucked and fixed to the platen 30 by a vacuum suction device.

The vacuum adsorption device is for adsorption and fixing the polishing pad 32 placed on the mounting surface of the platen 30 with a vacuum, and the vacuum adsorption device is adsorption formed on the mounting surface (upper surface) of the platen. Holes 202 and at least one vacuum line 204 formed in the platen body and connected to the suction holes 202 and the vacuum lines 204 to connect the polishing pad to the It has a vacuum pump 206 that provides a suction force to be fixed to the mounting surface. As shown in FIG. 3, the platen 30 has grooves 208 formed at the center and the edge of the mounting surface, and the suction holes 202 are positioned on the grooves 208.

For example, the holes may be evenly distributed throughout the mounting surface (upper surface) of the platen, as shown in FIG. 4, or variously arranged in the radial direction or the circumferential direction as shown in FIG. 5. Of course.

The method of attaching the polishing pad in the CMP facility as constant is as follows.

First remove the used polishing pad, and then wipe off any dirt on the upper surface of the platen. Place the new polishing pad on the platen to the top of the platen. The vacuum pump 206 is then operated to securely fix the polishing pad to the platen.

In the above, the configuration and operation of the CMP facility according to the present invention has been shown in accordance with the above description and drawings, but this is merely an example, and various changes and modifications are possible without departing from the technical spirit of the present invention. to be.

According to this invention, the polishing pad is reliably detached from the platen. In addition, there is an advantage that only a very small force is required to replace the polishing pad, and that no separate adhesive is required. As such, the CMP apparatus of the present invention can improve the efficiency of the replacement operation of the polishing pad.

Claims (5)

In chemical mechanical planarization (CMP) plants: A polishing pad; A platen having a mounting surface on which the polishing pad is mounted; And a device for suction fixing and fixing the polishing pad placed on the mounting surface of the platen with a vacuum. The method of claim 1, The vacuum adsorption device is Suction holes formed in the mounting surface of the platen; At least one vacuum line formed in the platen body and connected to the suction holes; And a vacuum pump connected to the vacuum line to provide suction to secure the polishing pad to the mounting surface. The method of claim 2, The mounting surface of the platen has a groove, And the suction holes are disposed on the grooves. The method of claim 2, And the groove is formed at the center and the edge of the mounting surface in a circumferential direction. The method of claim 2, And the holes are arranged at regular intervals in the radial or circumferential direction.