EP1281197A1 - Method of modifying the surface of a semiconductor wafer - Google Patents

Method of modifying the surface of a semiconductor wafer

Info

Publication number
EP1281197A1
EP1281197A1 EP00968554A EP00968554A EP1281197A1 EP 1281197 A1 EP1281197 A1 EP 1281197A1 EP 00968554 A EP00968554 A EP 00968554A EP 00968554 A EP00968554 A EP 00968554A EP 1281197 A1 EP1281197 A1 EP 1281197A1
Authority
EP
European Patent Office
Prior art keywords
group
wafer
polar component
article
abrasive
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP00968554A
Other languages
German (de)
English (en)
French (fr)
Inventor
John J. Gagliardi
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
3M Innovative Properties Co
Original Assignee
3M Innovative Properties Co
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 3M Innovative Properties Co filed Critical 3M Innovative Properties Co
Publication of EP1281197A1 publication Critical patent/EP1281197A1/en
Withdrawn legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
    • H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
    • H01L21/02002—Preparing wafers
    • H01L21/02005—Preparing bulk and homogeneous wafers
    • H01L21/02008—Multistep processes
    • H01L21/0201—Specific process step
    • H01L21/02024—Mirror polishing
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
    • H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
    • H01L21/04—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer
    • H01L21/18—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer the devices having semiconductor bodies comprising elements of Group IV of the Periodic Table or AIIIBV compounds with or without impurities, e.g. doping materials
    • H01L21/30—Treatment of semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/26
    • H01L21/302—Treatment of semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/26 to change their surface-physical characteristics or shape, e.g. etching, polishing, cutting
    • H01L21/306—Chemical or electrical treatment, e.g. electrolytic etching
    • H01L21/30625—With simultaneous mechanical treatment, e.g. mechanico-chemical polishing
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B24—GRINDING; POLISHING
    • B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
    • B24B37/00—Lapping machines or devices; Accessories
    • B24B37/04—Lapping machines or devices; Accessories designed for working plane surfaces
    • B24B37/042—Lapping machines or devices; Accessories designed for working plane surfaces operating processes therefor
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
    • H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
    • H01L21/04—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer
    • H01L21/18—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer the devices having semiconductor bodies comprising elements of Group IV of the Periodic Table or AIIIBV compounds with or without impurities, e.g. doping materials
    • H01L21/30—Treatment of semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/26
    • H01L21/31—Treatment of semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/26 to form insulating layers thereon, e.g. for masking or by using photolithographic techniques; After treatment of these layers; Selection of materials for these layers
    • H01L21/3105—After-treatment
    • H01L21/31051—Planarisation of the insulating layers
    • H01L21/31053—Planarisation of the insulating layers involving a dielectric removal step
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
    • H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
    • H01L21/04—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer
    • H01L21/18—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer the devices having semiconductor bodies comprising elements of Group IV of the Periodic Table or AIIIBV compounds with or without impurities, e.g. doping materials
    • H01L21/30—Treatment of semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/26
    • H01L21/31—Treatment of semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/26 to form insulating layers thereon, e.g. for masking or by using photolithographic techniques; After treatment of these layers; Selection of materials for these layers
    • H01L21/3205—Deposition of non-insulating-, e.g. conductive- or resistive-, layers on insulating layers; After-treatment of these layers
    • H01L21/321—After treatment
    • H01L21/32115—Planarisation
    • H01L21/3212—Planarisation by chemical mechanical polishing [CMP]
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B24—GRINDING; POLISHING
    • B24D—TOOLS FOR GRINDING, BUFFING OR SHARPENING
    • B24D2203/00—Tool surfaces formed with a pattern

Definitions

  • the invention relates to modifying a semiconductor wafer.
  • Wafers used in the fabrication of semiconductors often require surface modification, e.g., polishing and planarization, at some point during the fabrication process.
  • Traditional polishing methods include moving an abrasive substrate and the wafer in relation to each other, typically in the presence of a water-based solution. Polishing processes can be used to remove the highest points from the surface of a wafer. Polishing operations are performed on unprocessed and partially processed wafers.
  • a typical unprocessed wafer is crystalline silicon or another semiconductor material, e.g., gallium arsenide.
  • a typical wafer when ready for polishing has a top layer of a dielectric material such as glass, silicon dioxide or a metal conformally overlying one or more patterned layers.
  • the underlying patterned layers create local protrusions. Polishing smoothes the local features so that ideally the surface of the wafer is flat or planarized.
  • polishing is achieved through the solution working in combination with the fixed abrasive article in a chemical mechanical polishing process.
  • the chemical polishing of a silicon dioxide substrate occurs when a basic compound in a solution reacts with the silicon dioxide to form a surface layer of silicon hydroxides.
  • the mechanical process occurs when an abrasive article removes the metal hydroxides from the surface of the substrate.
  • Some chemical mechanical polishing techniques include orbiting or oscillating motions of either the article to be polished or of the polishing pad, or both.
  • Other chemical mechanical polishing techniques include a belt-shaped polishing pad that is advanced translationally under the article to be polished, and the article to be polished is rotated, oscillated or both across the surface of the belt-shaped pad.
  • a slurry is distributed between a pad and the surface to be polished. These slurries often contain water and abrasive particles.
  • the abrasive is fixed on a substrate and a polishing solution is distributed between the fixed abrasive and the surface to be polished.
  • the polishing pad and the substrate to be polished are hydrophobic, which inhibits wetting. Wetting facilitates the transport of fresh chemistry into the region between the abrasive surface and the surface of the wafer to be planarized.
  • the polishing liquid can also assist in the removal of debris and soluble material removed from the surface of the substrate being polished. Surfactants present in the composition can inhibit the removal rate. When a solution does not wet the abrasive surface, the polishing process can also be inhibited.
  • the polar component includes no greater than 8 carbon atoms.
  • the polar component is selected from the group consisting of alcohols, glycols, ketones, ethers, acetates, and combinations thereof.
  • the polar component includes an alcohol selected from the group consisting of methanol, ethanol, propanol, isopropanol, butanol, isobutanol and mixtures thereof. In some embodiments, the polar component is selected from the group consisting of acetone, ethyl acetate, cellosolve acetate, and mixtures thereof.
  • the fixed abrasive article includes a three-dimensional textured abrasive surface having a plurality of abrasive particles and a binder arranged in a pattern.
  • the fixed abrasive comprises particles selected from the group consisting of ceria, silica, alumina, titania, zirconia, manganese oxide, and mixtures thereof.
  • the method includes chemically and mechanically modifying the surface of the wafer.
  • the fixed abrasive article includes a backing and an abrasive coating on a surface of the backing, and the abrasive coating includes abrasive particles and a binder.
  • the polar component includes no greater than 8 carbon atoms.
  • the polar component is selected from the group consisting of alcohols, glycols, ketones, ethers, acetates, and combinations thereof.
  • the polar component includes an alcohol selected from the group consisting of methanol, ethanol, propanol, isopropanol, butanol, isobutanol and mixtures thereof.
  • the polar component is selected from the group consisting of acetone, ethyl acetate, cellosolve acetate, and mixtures thereof.
  • the fixed abrasive article includes a three- dimensional textured abrasive surface comprising a plurality of abrasive particles and a binder arranged in a pattern.
  • the composition used in the method preferably exhibits reduced surface tension relative to water and is able to wet hydrophobic substrates.
  • the method is particularly well suited to wetting abrasives that include hydrophobic oxide abrasives, e.g., cerium oxide particles.
  • the method also facilitates web polishing by maintaining the solution within the confines of the web such that it does not seep underneath the web where it might cause mechanical difficulties.
  • the improved wetting also provides good rates of removal of surface material.
  • the composition also provides good low vibration and friction during chemical mechanical planarization operations.
  • aqueous polishing solutions tend to form large beads of liquid when in contact with a hydrophobic web.
  • the large beads tend to be mobile on the abrasive surface during polishing.
  • the solution travels beyond the edge of the abrasive surface and seeps between the abrasive surface polishing pad and the sub pad on which the fixed abrasive polishing pad sits. This can cause the polishing pad to stick to the sub pad, which in turn causes mechanical problems.
  • the method of modifying a surface of a semiconductor wafer includes contacting the wafer with a fixed abrasive article in the presence of a composition that includes water and a polar component, and moving at least one of the wafer and the fixed abrasive article relative to each other so as to modify the surface of the wafer.
  • the method preferably modifies the surface of the wafer to achieve a surface that is more planar or uniform, or less rough, or a combination thereof, relative to the wafer surface prior to treatment.
  • the polar component preferably provides a composition that is capable of sufficiently wetting the hydrophobic substrate to be modified as well as the fixed abrasive pad.
  • the polar component includes no greater than 8 carbon atoms.
  • useful polar components include alcohols, e.g., methanol, ethanol, propanol, isopropanol, n-butanol, sec-butanol, tert-butanol, isobutanol, and octanol; acetates including methyl acetate, ethyl acetate, and cello solve acetate; ketones, e.g., acetone; ketone alcohols, e.g. diacetone alcohol; ethers including, e.g., methyl ether; alkylene glycols or thioglycols containing a C 2 - C 6 alkylene group, e.g.
  • alcohols e.g., methanol, ethanol, propanol, isopropanol, n-butanol, sec-butanol, tert-butanol, isobutanol, and octanol
  • poly(alkylene-glycol)s and thioglycols e.g. diethylene glycol, thiodiglycol, polyethylene glycol and polypropylene glycol
  • polyols e.g.
  • glycerol and 1,2,6-hexanetriol and lower alkyl glycol and polyglycol ethers, e.g.2-methoxyethanol, 2-(2-methoxyethoxy)ethanol, 2-(2-ethoxyethoxy)ethanol, 2-(2-butoxyethoxy)ethanol,3-butoxypropan-l-ol, 2-[2- (2-methoxyethoxy)-ethoxy]ethanol, 2-[2-(2-ethoxyethoxy)ethoxy]-ethanol; cyclic esters and cyclic amides, e.g. substituted pyrollidones; sulpholane; multiple functionality polar components; and mixtures thereof.
  • lower alkyl glycol and polyglycol ethers e.g.2-methoxyethanol, 2-(2-methoxyethoxy)ethanol, 2-(2-ethoxyethoxy)ethanol, 2-(2-butoxyethoxy)ethanol,3-butoxypropan-l-ol, 2-[2- (2-methoxye
  • the pH of the composition is selected to be suitable for the substrate being modified.
  • Useful compositions have a pH of greater than 1.5, more preferably from about 3 to about 12.5, most preferably from about 5 to about 12.
  • Additives can be included in the composition to achieve a desired pH. Examples of such additives include bases, e.g., potassium hydroxide and ammonium hydroxide, and acids, e.g., KIO 3 , potassium phthalate, phthalic acid, phosphoric acid, nitric acid, and sulfuric acid. Buffers can also be included in the composition to maintain the desired pH.
  • the composition may also include other components including, e.g., liquid etchants, e.g., strong acids (e.g., sulfuric acid and hydrofluoric acid) and oxidizing gents (e.g., peroxides), lubricants and combinations thereof
  • suitable lubricants include metal salts of fatty acids including, e.g., zinc stearate, calcium stearate and lithium stearate, graphite, mica, molybdenum disulfide, talc, polyamides, boron nitride, sulfides, waxes, silicone compounds, polyvinyl acetate, polyvinyl alcohols, polymers, and combinations thereof.
  • the method is suitable for use with a variety of fixed abrasive articles.
  • useful fixed abrasive articles include those fixed abrasive articles that are in the form of a pad or a web, e.g., a continuous belt.
  • the fixed-abrasive article preferably includes a number of abrasive particles in a binder attached to a substrate, e.g., a backing.
  • the abrasive particles in the binder may be in the form of an abrasive coating (e.g., a continuous or discontinuous coating), abrasive composites (e.g., shaped bodies) or a combination thereof.
  • the abrasive components may be arranged in a pattern or random configuration.
  • the fixed abrasive article can be textured such that it includes raised portions and recessed portions.
  • the fixed abrasive article can also be three-dimensional such that it includes numerous abrasive particles extending throughout at least a portion of its thickness such that removing some of the abrasive particles during the surface modifying process exposes additional abrasive particles capable of performing the surface modifying function. Examples of useful fixed abrasive articles are described in U.S. Patent Nos. 5,958,794, 5,692,950 and 5,990,012.
  • the abrasive article may include any number of different abrasive particles.
  • Suitable abrasive particles include, e.g., ceria, silica, alumina, iron oxide, chromia, titania, tin oxide, zirconia, manganese oxide and combinations thereof.
  • Other useful abrasive particles include fused aluminum oxide, heat treated aluminum oxide, white fused aluminum oxide, black silicon carbide, green silicon carbide, titanium diboride, boron carbide, silicon nitride, tungsten carbide, titanium carbide, diamond, cubic boron nitride, hexagonal boron nitride, garnet, fused alumina zirconia, alumina-base sol gel derived abrasive particles and combinations thereof.
  • the movement of at least one of the abrasive article and the wafer relative to each other to modify a surface of the wafer can be rotational, e.g., in a circular, spiral, elliptical, or non uniform fashion, in a figure eight or a corkscrew, translational, vibrational, oscillatory, or a combination thereof.
  • the movement includes rotation of one or both of the fixed abrasive article and the wafer.
  • the wafer and the abrasive article can be rotated in a circular fashion and in the same direction.
  • the wafer and the fixed abrasive article can be rotated in opposite directions.
  • the semiconductor wafer may be in a variety of forms including, e.g., a blank wafer (i.e., a wafer prior to processing, e.g., prior to adding topographical features such as metallized and insulating areas) or a processed wafer (i.e., a wafer that has been subjected to one or more processing steps to add topographical features to the wafer surface).
  • the wafer can include a number of materials including, e.g., silicon, silicon dioxide, silicon nitride, gallium arsenide, copper, aluminum, tungsten, titanium, titanium nitride, polymer, and combinations thereof.
  • the article to be modified can be a variety of articles and can include materials such as silicon, silicon dioxide, silicon nitride, gallium arsenide, copper, aluminum, tungsten, titanium, titanium nitride, polymers, and combinations thereof.

Landscapes

  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Condensed Matter Physics & Semiconductors (AREA)
  • General Physics & Mathematics (AREA)
  • Manufacturing & Machinery (AREA)
  • Computer Hardware Design (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Power Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Mechanical Treatment Of Semiconductor (AREA)
  • Crystals, And After-Treatments Of Crystals (AREA)
  • Grinding And Polishing Of Tertiary Curved Surfaces And Surfaces With Complex Shapes (AREA)
EP00968554A 2000-04-28 2000-10-02 Method of modifying the surface of a semiconductor wafer Withdrawn EP1281197A1 (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
US56097300A 2000-04-28 2000-04-28
US560973 2000-04-28
PCT/US2000/027091 WO2001084613A1 (en) 2000-04-28 2000-10-02 Method of modifying the surface of a semiconductor wafer

Publications (1)

Publication Number Publication Date
EP1281197A1 true EP1281197A1 (en) 2003-02-05

Family

ID=24240135

Family Applications (1)

Application Number Title Priority Date Filing Date
EP00968554A Withdrawn EP1281197A1 (en) 2000-04-28 2000-10-02 Method of modifying the surface of a semiconductor wafer

Country Status (9)

Country Link
EP (1) EP1281197A1 (zh)
JP (1) JP2003533023A (zh)
KR (1) KR20020093991A (zh)
CN (1) CN1452784A (zh)
AU (1) AU2000278447A1 (zh)
BR (1) BR0017222A (zh)
CA (1) CA2407300A1 (zh)
HK (1) HK1054465A1 (zh)
WO (1) WO2001084613A1 (zh)

Families Citing this family (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6682575B2 (en) 2002-03-05 2004-01-27 Cabot Microelectronics Corporation Methanol-containing silica-based CMP compositions
KR100623963B1 (ko) * 2005-01-12 2006-09-19 제일모직주식회사 금속배선 연마용 슬러리 조성물 및 이를 이용한 금속배선연마 방법
CN102891077B (zh) * 2012-09-26 2015-12-09 复旦大学 采用水基原子层沉积技术在石墨烯表面制备高k栅介质的方法
JP6358740B2 (ja) * 2014-04-08 2018-07-18 山口精研工業株式会社 研磨用組成物
JP6358739B2 (ja) * 2014-04-08 2018-07-18 山口精研工業株式会社 研磨用組成物
CN104842265A (zh) * 2015-06-18 2015-08-19 上海申航热能科技有限公司 管内壁抛光用磨头及配方
CN106002498B (zh) * 2016-08-01 2018-04-06 中国电子科技集团公司第四十六研究所 一种有机dast晶体的表面研磨工艺方法
CN113881349B (zh) * 2021-09-01 2022-10-21 上海工程技术大学 用于碳化硅晶片硅表面化学机械抛光的抛光液及抛光方法

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DE3735158A1 (de) * 1987-10-16 1989-05-03 Wacker Chemitronic Verfahren zum schleierfreien polieren von halbleiterscheiben
US5614444A (en) * 1995-06-06 1997-03-25 Sematech, Inc. Method of using additives with silica-based slurries to enhance selectivity in metal CMP
US5704987A (en) * 1996-01-19 1998-01-06 International Business Machines Corporation Process for removing residue from a semiconductor wafer after chemical-mechanical polishing
US5972792A (en) * 1996-10-18 1999-10-26 Micron Technology, Inc. Method for chemical-mechanical planarization of a substrate on a fixed-abrasive polishing pad
JP2002517593A (ja) * 1998-06-10 2002-06-18 ロデール ホールディングス インコーポレイテッド 金属ｃｍｐにおける研磨用組成物および研磨方法

Non-Patent Citations (1)

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Title
See references of WO0184613A1 *

Also Published As

Publication number Publication date
JP2003533023A (ja) 2003-11-05
CA2407300A1 (en) 2001-11-08
AU2000278447A1 (en) 2001-11-12
BR0017222A (pt) 2003-01-07
HK1054465A1 (zh) 2003-11-28
WO2001084613A1 (en) 2001-11-08
KR20020093991A (ko) 2002-12-16
CN1452784A (zh) 2003-10-29

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