Patent Application
20170113321
The present invention is related to a CMP conditioner, particularly to a hybridized CMP conditioner.
Chemical mechanical polishing (CMP) is a flattening technology commonly used in semiconductor processing. In a common CMP processing, an abrasive pad (or polishing pad) fixed at a rotary table is used to contact with and apply a force to a silicon wafer carried on a spinning carrier. The carrier and the rotary table are rotated, while an abrasive slurry is supplied to the abrasive pad during polishing. In general, fragments derived by abrasion and the abrasive slurry are accumulated in pores of the abrasive pad, such that the abrasive pad is consumed and the effect of abrasion on semiconductor is then reduced. Therefore, it is necessary to use a conditioner for the removal of fragments and abrasive slurry remained in the abrasive pad.
A hybridized conditioner is proposed for enabling the conditioner to combine with abrasive materials of a variety of types, sizes and shapes. For instance, Taiwan patent No. I383860 B1 discloses a hybridized conditioner, including a large substrate provided with a bonding face, a bottom face, and a plurality of penetrating holes or a plurality of accommodating slots; a plurality of abrasive units including a plurality of abrasive grits, respectively; the plurality of abrasive grits including a plurality of cutting tips, respectively; a plurality of penetrating holes or a plurality of accommodating slots for accommodating a plurality of abrasive units, respectively, the plurality of cutting tips protruding out of the bonding face, respectively; the plurality of abrasive units and the large substrate are fixedly bonded by means of bonding agent; the plurality of cutting tips of the plurality of abrasive grits are varied from a plane within 20 μm in height, respectively. It is easier for the cutting tips of most of abrasive grits of the large-area hybridized conditioner to be dimensioned at the same height. Various abrasive grits as desired are possible. Moreover, the cost for manufacturing a plurality of small abrasive units to be assembled as a large-area conditioner is lower.
U.S. Pat. No. 8,398,466 B2 discloses CMP pad conditioners with mosaic abrasive segments and associated methods, comprising a plurality of abrasive segments and a pad conditioner substrate. Each abrasive segment includes a segment blank and an abrasive layer attached to the segment blank. The abrasive layer includes a superhard abrasive material, which is a polycrystalline diamond (PCD) blade and individual abrasive particles. Each of the abrasive segments is permanently affixed to the pad conditioner substrate in an orientation that enables removal of material from a CMP pad by the abrasive layer as the pad conditioner and the CMP pad are moved relative to one another.
Taiwan patent No. I 388398 B1 discloses CMP pad dressers with hybridized abrasive surface and related methods, comprising a plurality of blade-like abrasive segments, a plurality of particle-like abrasive segments and a pad conditioner substrate. Each blade-like abrasive segment includes a blade-like abrasive blank and an abrasive layer attached to the blade-like abrasive blank. The abrasive layer includes a superhard abrasive material. Each particle-like abrasive segment includes a particle-like abrasive blank and an abrasive layer attached to the particle-like abrasive blank. The abrasive layer includes a plurality of superhard abrasive particles. The blade-like abrasive segments and the particle-like abrasive segments are affixed on the pad conditioner substrate in alternate patterns that enables removal of material from a CMP pad as the pad conditioner and the CMP pad are moved relative to one another. All the aforementioned prior technologies disclose a hybridized pad conditioner with two abrasive structures. However, all of these structures are presented as discontinuous abrasive segments. Thus, the conditioning capability should still be improved.
In addition, Taiwan patent application No. 104105264, filed by the applicant of the present invention, discloses a CMP conditioner, comprising a base, a plurality of conditioning posts and a plurality of sliders. The surface of the base is divided into a central surface and a peripheral surface concentrically. The central surface is depressed to be a concave portion. The peripheral surface surrounding the central surface is depressed to form a plurality of mounting holes. Each conditioning post is mounted in the mounting hole, correspondingly, and is provided with a post body and an abrasive material. The abrasive material is mounted on the surface of the post body. The sliders are provided on the peripheral surface and spread between the mounting holes. Each slider is provided with a conditioning face. In the aforementioned prior art, the slider is provided with a smooth or unsmooth conditioning face. Further, on the conditioning face of the slider, a diamond film or diamond-like carbon film may be plated. However, the abrasive tip is absent on either diamond film or diamond-like carbon film. Thus, conditioning capability is still insufficient.
It is the main object of the present invention to solve the problem of insufficient conditioning capability of the conventional hybridized CMP conditioner.
For achieving the above object, the present invention provides a hybridized CMP conditioner comprising a base, a first abrasive unit and a plurality of second abrasive units. The first abrasive unit is provided on the base and comprises a first bonding layer fixed on the base, a substrate for abrasive unit provided on the first bonding layer and an abrasive layer provided on the substrate for abrasive unit. The abrasive layer is a diamond coating formed by means of a chemical vapor deposition process, and the diamond coating is provided on the surface thereof with a plurality of abrasive tips. Each second abrasive unit is provided on the base and comprises a second bonding layer fixed on the base, a carrying post provided on the second bonding layer, an abrasive particle provided on the carrying post and an abrasive material-bonding layer provided between the carrying post and the abrasive particle, respectively.
In one embodiment, the base is provided on the surface thereof with a central region and an annular outer region around the outside of the central region.
In one embodiment, the central region is provided with a recessed portion for the first abrasive unit to be provided therein, and the annular outer region is provided with a plurality of first accommodating portions spaced apart from each other for the second abrasive units to be provided therein.
In one embodiment, each of the first accommodating portions is presented as a through-hole structure or a concave hole structure.
In one embodiment, the central region is provided with a plurality of second accommodating portions spaced apart from each other for accommodating the second abrasive units, and the annular outer region is provided with a recessed portion for the first abrasive unit to be provided therein.
In one embodiment, each of the second accommodating portions is presented as a through-hole structure or a concave hole structure.
In one embodiment, the central region and the annular outer region are provided with a recessed portion for the first abrasive unit to be provided therein, and the base further comprises a plurality of third accommodating portions provided in the first abrasive unit for accommodating the second abrasive units.
In one embodiment, each of the third accommodating portions is presented as a through-hole structure or a concave hole structure.
In one embodiment, the base further comprises an annular inner region on the surface thereof the annular inner region surrounding the inner side of the central region, and the annular inner region being provided with a plurality of fourth accommodating portions spaced apart from each other for accommodating the second abrasive units.
In one embodiment, each of the fourth accommodating portions is presented as a through-hole structure or a concave hole structure.
In one embodiment, the central region is provided with a recessed portion for the first abrasive unit to be provided therein.
In one embodiment, the base is a plane substrate.
In one embodiment, the second abrasive units are presented as a patterned arrangement, the patterned arrangement being selected from the group consisting of an equally spaced arrangement, unequally spaced arrangement, single annulus arrangement and multi-annuli arrangement.
In one embodiment, the number of the second abrasive units is in the range of 2 to 300.
In one embodiment, the abrasive particle is selected from the group consisting of synthetic diamond, natural diamond, polycrystalline diamond and cubic boron nitride.
In one embodiment, the first bonding layer, the second bonding layer and the abrasive material-bonding layer are made of material selected from the group consisting of ceramic material, brazing material, electroplating material, metal material and polymer material.
In one embodiment, the brazing material is selected from the group consisting of Fe, Co, Ni, Cr, Mn, Si, B, C and Al.
In one embodiment, the polymer material is selected from the group consisting of epoxy resin, polyester resin, polyacrylate resin and phenolic resin.
In one embodiment, the base and the carrying post are made of material selected from the group consisting of stainless steel, metal material, plastic material and ceramic material.
In one embodiment, the material of the substrate for abrasive unit is selected from the group consisting of silicon carbide, silicon, polycrystalline alumina, monocrystalline alumina and diamond.
In one embodiment, a particle diameter of the abrasive particle is in the range of 500 μm to 1200 μm.
In the aforementioned prior art, all the hybridized pad conditioners, disclosed in U.S. Pat. No. 8,398,466 and in Taiwan patent No. 1388398, are all presented as discontinuous abrasive segments. In the present invention, however, the diamond coating (the first abrasive unit) with continuous structure is in cooperation with the abrasive particles (the second abrasive units) with discontinuous structure. In comparison with the prior art, therefore, in the present invention, the diamond coating is capable of providing the abrasive effect of high flatness with reduction in surface roughness of the polishing pad, while the abrasive particles are provided with effective cutting force and surface removal force. The hybridized CMP conditioner is provided with excellent cutting force and flattening capability at the same time, by way of integration of the diamond coating and the abrasive particles into one single CMP conditioner.
In Taiwan patent No. 104105264 filed by the applicant of the present invention, additionally, the abrasive tip is absent on the conditioning face of the slider. In contrast, effective cutting force may be provided by means of the second abrasive units.
The detailed description and technical content of the present invention will be described, in conjunction with drawings, as follows.
Referring to
In the present invention, the first bonding layer 21 and the second bonding layer 31 may be made of material selected from ceramic material, brazing material, electroplating material, metal material or polymer material. Polymer material is preferred. In this case, the brazing material may be metal or alloy of Fe, Co, Ni, Cr, Mn, Si, Al, B, C. In one embodiment, alloy of Nicrobraz LM of composition 7 wt % Cr, 3.1 wt % B, 4.5 wt % Si, 3.0 wt % Fe, 0.06 wt % C, and Ni for the rest may be used as brazing material. The polymer material may be epoxy resin, polyester resin, polyacrylate resin or phenolic resin. The second bonding layer 31 is preferably made of epoxy resin. The material of the substrate for abrasive unit 22 may be silicon carbide, silicon, polycrystalline alumina, monocrystalline alumina or diamond. In the present invention, the base 10 and/or the carrying post 32 is preferably made of stainless steel, while the substrate for abrasive unit 22 is preferably made of silicon carbide. In the present invention, however, any variation as desired by the user is possible, without being limited thereto.
In this embodiment, the base 10 is provided on the surface thereof with a central region 11 and an annular outer region 12 around the outside of the central region 11. The central region 11 is provided with a recessed portion 111. The annular outer region 12 is provided with a plurality of first accommodating portions 40a spaced apart from each other. The first abrasive unit 20 is provided in the recessed portion 111, while the second abrasive units 30 are provided in the first accommodating portions 40a. In this embodiment, four first accommodating portions 40a are provided symmetrically and corresponded to the second abrasive units 30. In this way, the first abrasive unit 20 is then provided in the inner annulus of the base 10, while the second abrasive units 30 are provided in the outer annulus of the base 10.
Referring to
The number and the arrangement of the accommodating portions 40a, 40b, 40c, 40d and the second abrasive units 30, described above and illustrated in the figures, are exemplary, but not limited thereto. The present invention may be varied arbitrarily depending upon the requirement of the user. For instance, both the number of the accommodating portions 40a, 40b, 40c, 40d and that of the second abrasive units 30 may be in the range of 2 to 300. Moreover, both the accommodating portions 40a, 40b, 40c, 40d and the second abrasive units 30 are presented as a patterned arrangement. The patterned arrangement may be an equally spaced arrangement, unequally spaced arrangement, single annulus arrangement, multi-annuli arrangement, or a combination thereof.
To sum up, the effect of the present invention, in comparison with the prior art, is that the diamond coating is capable of providing the abrasive effect of high flatness with reduction in surface roughness of the polishing pad, while the abrasive particles are provided with effective cutting force and surface removal force. The hybridized CMP conditioner is provided with excellent cutting force and flattening capability at the same time, by way of integration of the diamond coating and the abrasive particles into one single CMP conditioner.
While this invention has been detailed described in connection with what is presently considered to be preferred embodiments, it should be understood that the invention is not limited to the disclosed embodiments. That is to say, various variations and modifications made in accordance with the patent claims should fall within the scope of the present invention.
| Number | Date | Country | Kind |
|---|---|---|---|
| 104135197 | Oct 2015 | TW | national |
