Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B24—GRINDING; POLISHING
  • B24D—TOOLS FOR GRINDING, BUFFING OR SHARPENING
  • B24D3/00—Physical features of abrasive bodies, or sheets, e.g. abrasive surfaces of special nature; Abrasive bodies or sheets characterised by their constituents
  • B24D3/02—Physical features of abrasive bodies, or sheets, e.g. abrasive surfaces of special nature; Abrasive bodies or sheets characterised by their constituents the constituent being used as bonding agent
  • B24D3/04—Physical features of abrasive bodies, or sheets, e.g. abrasive surfaces of special nature; Abrasive bodies or sheets characterised by their constituents the constituent being used as bonding agent and being essentially inorganic
  • B24D3/06—Physical features of abrasive bodies, or sheets, e.g. abrasive surfaces of special nature; Abrasive bodies or sheets characterised by their constituents the constituent being used as bonding agent and being essentially inorganic metallic or mixture of metals with ceramic materials, e.g. hard metals, "cermets", cements
  • B24D3/10—Physical features of abrasive bodies, or sheets, e.g. abrasive surfaces of special nature; Abrasive bodies or sheets characterised by their constituents the constituent being used as bonding agent and being essentially inorganic metallic or mixture of metals with ceramic materials, e.g. hard metals, "cermets", cements for porous or cellular structure, e.g. for use with diamonds as abrasives
• • C—CHEMISTRY; METALLURGY
  • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
  • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
  • C23C18/00—Chemical coating by decomposition of either liquid compounds or solutions of the coating forming compounds, without leaving reaction products of surface material in the coating; Contact plating
  • C23C18/16—Chemical coating by decomposition of either liquid compounds or solutions of the coating forming compounds, without leaving reaction products of surface material in the coating; Contact plating by reduction or substitution, e.g. electroless plating
  • C23C18/48—Coating with alloys
  • C23C18/50—Coating with alloys with alloys based on iron, cobalt or nickel
• • C—CHEMISTRY; METALLURGY
  • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
  • C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
  • C25D3/00—Electroplating: Baths therefor
  • C25D3/02—Electroplating: Baths therefor from solutions
  • C25D3/56—Electroplating: Baths therefor from solutions of alloys
  • C25D3/562—Electroplating: Baths therefor from solutions of alloys containing more than 50% by weight of iron or nickel or cobalt
• • C—CHEMISTRY; METALLURGY
  • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
  • C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
  • C25D3/00—Electroplating: Baths therefor
  • C25D3/02—Electroplating: Baths therefor from solutions
  • C25D3/56—Electroplating: Baths therefor from solutions of alloys
  • C25D3/567—Electroplating: Baths therefor from solutions of alloys containing more than 50% by weight of platinum group metals
• • C—CHEMISTRY; METALLURGY
  • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
  • C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
  • C25D5/00—Electroplating characterised by the process; Pretreatment or after-treatment of workpieces
  • C25D5/10—Electroplating with more than one layer of the same or of different metals
  • C25D5/12—Electroplating with more than one layer of the same or of different metals at least one layer being of nickel or chromium
  • C25D5/14—Electroplating with more than one layer of the same or of different metals at least one layer being of nickel or chromium two or more layers being of nickel or chromium, e.g. duplex or triplex layers
• • C—CHEMISTRY; METALLURGY
  • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
  • C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
  • C25D5/00—Electroplating characterised by the process; Pretreatment or after-treatment of workpieces
  • C25D5/627—Electroplating characterised by the visual appearance of the layers, e.g. colour, brightness or mat appearance

Definitions

• the present invention relates to a diamond tool, and more particularly, to a diamond tool for a CMP pad, which has a good corrosion resistance in slurry environment for semiconductor CMP.
• CMP Chemical Mechanical Planarization
• the CMP process is performed by relative rotation between a wafer as a workpiece and a polyurethane pad which are pressed to and contact with each other.
• slurry is supplied between the wafer and the pad, so that the slurry assists chemical and mechanical polishing. That is, the mechanical polishing is effected by abrasive particles contained in the slurry and a plurality of projections of the pad, while the chemical polishing is effected by chemical reaction of a surface of the wafer with chemical components contained in the slurry.
• a plurality of the projections formed on the polyurethane pad fall down due to wear or pressure with the passage of the polishing time, so that the polishing ability of the pad is reduced.
• a diamond tool which is referred to as a diamond conditioner or diamond dresser, is used.
• Such a diamond tool is manufactured by bonding diamonds onto a body (herein after, referred to as the shank) of general stainless steel or carbon steel by nickel electroplating. Otherwise, for manufacturing the tool, the diamonds and the shank are bonded by melting metal or alloy therebetween. Generally, the former is referred to as an electroplating or electrodepositing method, and the latter is referred to as a fusion deposition or brazing method. The material for bonding the diamonds onto the shank is referred to as metal bond or binder.
• the diamond generally designates artificial or natural diamond and cubic boron nitride (cBN), it is previously clarified that the term "daimond” additionally means silicone carbide, alumina, superabrasive, or a combination thereof.
• chrome coating has been used as economical means for improving the corrosion resistance. Since the chrome is not large in the electrochemical potential difference between the chrome and the plating layer, i.e. the bonding layer, the chrome has small possibility of hetero-junction corrosion observed in the platinum group metal coating. In addition, the chrome can provide glossy, elegant appearance. However, since the chrome is inferior in its own corrosion resistance and has high hardness and internal stress as compared with the platinum group metal, the thickness of the coating layer is limited to the extent of maximum 1 ⁇ m. Furthermore, there is a disadvantage in that the bonding layer of the ceramic, which is superior in corrosion resistance, cannot be applied to a conventional metal bonding process, or needs much time and equipment investment in the bonding process.
• Fig. 1 shows a surface of a diamond tool or conditioner, on which diamonds are bonded.
• diamonds 1 are regularly (or irregularly) arranged and bonded on the shank 2.
• the shank 2 may change in its shape into a circular disk or bar shape according to its use or application, although the circular disk-shaped shank 2 is shown in Fig. 1.
• Fig. 2 is a photomicrograph of the diamonds 1 bonded onto the shank 2, wherein the diamonds 1 are securely bonded by a bonding layer 3 of nickel or alloy thereof.
• the bonding layer 3 may be formed by means of the conventional electroplating, electroless plating, or brazing.
• FIG. 3 schematically shows a cross-section of a portion of the diamond tool shown in Fig. 1.
• a shank layer 4 of stainless steel or the like is provided as the lowest layer; the diamonds 1 are positioned on the shank layer 4; and the bonding layer 3 functions to bond the diamonds 1 onto the shank layer 4.
• Fig. 4 is a photomicrograph showing a cross-section of the diamond tool corresponding to that shown in Fig. 3.
• Fig. 5 is a schematic sectional view of the diamond tool used in corrosive environment, wherein a coating layer 5 is formed on the bonding layer 3 in order to improve the corrosion resistance.
• the coating layer 5 comprises palladium, rhodium, or platinum of the platinum group, or chrome having good acid resistance.
• the coating layer 5 generally shows good corrosion resistance in the corrosive environment, due to its high hardness, as shown in Fig. 7, the cracks can be easily generated in practical use. Therefore, examples of corrosion and thus removal of the diamonds shown in Fig. 8 have been reported.
• the present invention is conceived to solve the problems in the prior art.
• An object of the present invention is to provide a diamond tool, which can have the advantages of platinum group metal coating and chrome coating.
• Another object of the present invention is to provide a diamond tool of which corrosion resistance is superior against ceria slurry and metal slurry and which can be easily manufactured.
• the diamond conditioner is manufactured by coating the bonding layer 3 with the palladium-nickel or the palladium-cobalt alloy and optionally coating the alloy coating layer with the chrome as an upper layer.
• the diamond conditioner of the present invention since the diamond conditioner of the present invention has the superior corrosion resistance and the using stability as compared with a conventional diamond conditioner with single layer coating of pure platinum group metal or chrome, the diamond conditioner of the present invention can be stably used in the ceria slurry solution or the metal slurry solution having the high corrosiveness.
• a diamond tool comprising a plurality of diamonds bonded onto a shank by a bonding layer, and a coating layer which is formed on the bonding layer and comprises palladium alloy.
• a thickness of the coating layer is in the range from 0.1 to 3 ⁇ m.
• the palladium alloy may comprise palladium-nickel alloy, and the content of nickel added to the palladium may be in the range from 10 to 50 %.
• the palladium alloy may comprise palladium-cobalt alloy, and the content of cobalt added to the palladium may be in the range from 5 to 40 %.
• the diamond tool of the present invention may further comprise a chrome coating layer formed on the coating layer, wherein a thickness of the chrome coating layer may be in the range from 0.01 to 1.0 ⁇ m, preferably from 0.1 to 0.9 ⁇ m.
• the diamond tool may comprise a diamond conditioner for a CMP pad.
• the diamond may comprise artificial or natural diamond, cubic boron nitride, silicone carbide, alumina, or combinations thereof.
• Fig. 1 is a schematic view of a diamond tool.
• Fig. 2 is a photomicrograph of a surface of the diamond tool.
• Fig. 3 is a schematic sectional view of the diamond tool.
• Fig. 4 is a photomicrograph of a cross-section of the diamond tool.
• Fig. 5 is a schematic sectional view of a diamond tool with a coating layer formed on a bonding layer.
• Fig. 6 is a schematic sectional view of a diamond tool with a plurality of coating layers formed on the bonding layer.
• Fig. 7 is a photomicrograph showing a corrosion test result (removal of diamonds) of the diamond tool with its surface coated by a conventional method.
• Fig. 8 is a photomicrograph showing a corrosion test result (surface cracks) of the diamond tool with its surface coated by the conventional method. Best Mode for Carrying Out the Invention
• the coating layer 5 that has the superior corrosion resistance and ductility for reducing the possibility of generation of the cracks. Alloy rather than a conventional single element is effective as such a coating layer, and palladium-nickel (Pd-Ni) alloy and palladium-cobalt (Pd-Co) alloy are used as a coating layer in the present invention.
• the palladium-nickel alloy coating layer can be formed by electroplating or electroless plating. Although the nickel of the alloy functions to improve the ductility of the coating layer, the nickel of 10 % or less is not effective. The nickel of 50 % or more causes the corrosion resistance to be deteriorated.
• the thickness of the coating layer is preferably in the range from 0.1 to 3 ⁇ m. If the thickness of the coating layer is 0.1 ⁇ m or less, the coating layer does not exhibit sufficient corrosion resistance. Further, if the thickness of the coating layer is 3 ⁇ m or more, the coating layer no longer improves the corrosion resistance.
• the palladium-cobalt alloy coating layer can be formed by the same methods as the foregoing. It is found out that the cobalt of the alloy is effective in the range from 5 % to 40 %. While the cobalt of 5 % or less does not improve the ductility, the cobalt of 40 % or more shows rapid degradation of the corrosion resistance. Its thickness is preferably in the range from 0.1 to 3 ⁇ m for the above reasons.
• the palladium-nickel and the palladium-cobalt alloy coating layers show superior properties in CMP environment, where ceria slurry solution and metal slurry solution are used.
• chrome plating which provides high hardness and elegant appearance is performed.
• a plurality of coating layers comprising the palladium alloy coating layer 5 and the chrome coating layer 6 are formed, as shown in Fig. 6.
• the chrome coating may be performed by a conventional electroplating or dry plating.
• the thickness of the chrome coating layer 6 is in the range from 0.01 to 1.0 ⁇ m, preferably from 0.1 to 0.9 ⁇ m, wherein the thickness of 0.01 ⁇ m or less does not show sufficient corrosion resistance, while the thickness of 1.0 ⁇ m or more has possibility of cracks with the passage of time.
• the corrosive slurry gets in direct contact with the chrome coating layer.
• the chrome coating layer is damaged, the underlying palladium alloy coating layer also comes into contact with the corrosive solution. If both coating layers are exposed to the corrosive environment, the chrome coating is selectively corroded since the chrome has electrochemically lower potential.
• the chrome coating provides sacrifice anode effects protecting the lower layer, increasing the endurance limit of the entire coating layers.

Landscapes

• Chemical & Material Sciences (AREA)
• Engineering & Computer Science (AREA)
• Metallurgy (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Materials Engineering (AREA)
• Organic Chemistry (AREA)
• Electrochemistry (AREA)
• Mechanical Engineering (AREA)
• General Chemical & Material Sciences (AREA)
• Ceramic Engineering (AREA)
• Inorganic Chemistry (AREA)
• Chemically Coating (AREA)
• Other Surface Treatments For Metallic Materials (AREA)
• Polishing Bodies And Polishing Tools (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=34858726

Family Applications (1)

Country Status (2)

Cited By (1)

Families Citing this family (4)

Citations (6)

• 2004
  • 2004-02-17 KR KR1020040010266A patent/KR100582962B1/ko active IP Right Grant
  • 2004-07-02 WO PCT/KR2004/001643 patent/WO2005078162A1/en active Application Filing

Patent Citations (6)

Also Published As

Similar Documents

Legal Events