US20150266155A1 - Method for producing polished-article - Google Patents

Method for producing polished-article Download PDF

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Publication number
US20150266155A1
US20150266155A1 US14/722,222 US201514722222A US2015266155A1 US 20150266155 A1 US20150266155 A1 US 20150266155A1 US 201514722222 A US201514722222 A US 201514722222A US 2015266155 A1 US2015266155 A1 US 2015266155A1
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United States
Prior art keywords
grinding
polished
article
polishing
grinding wheel
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.)
Abandoned
Application number
US14/722,222
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English (en)
Inventor
Kazumasa Kitamura
Tomoki Nagae
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.)
NGK Insulators Ltd
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NGK Insulators Ltd
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
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Assigned to NGK INSULATORS, LTD. reassignment NGK INSULATORS, LTD. ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: KITAMURA, KAZUMASA, NAGAE, TOMOKI
Publication of US20150266155A1 publication Critical patent/US20150266155A1/en
Abandoned legal-status Critical Current

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Classifications

    • 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
    • B24B9/00—Machines or devices designed for grinding edges or bevels on work or for removing burrs; Accessories therefor
    • B24B9/02—Machines or devices designed for grinding edges or bevels on work or for removing burrs; Accessories therefor characterised by a special design with respect to properties of materials specific to articles to be ground
    • B24B9/06—Machines or devices designed for grinding edges or bevels on work or for removing burrs; Accessories therefor characterised by a special design with respect to properties of materials specific to articles to be ground of non-metallic inorganic material, e.g. stone, ceramics, porcelain
    • B24B9/065—Machines or devices designed for grinding edges or bevels on work or for removing burrs; Accessories therefor characterised by a special design with respect to properties of materials specific to articles to be ground of non-metallic inorganic material, e.g. stone, ceramics, porcelain of thin, brittle parts, e.g. semiconductors, wafers
    • 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
    • B24B37/044—Lapping machines or devices; Accessories designed for working plane surfaces operating processes therefor characterised by the composition of the lapping agent
    • 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
    • B24B37/07—Lapping machines or devices; Accessories designed for working plane surfaces characterised by the movement of the work or lapping tool
    • B24B37/08—Lapping machines or devices; Accessories designed for working plane surfaces characterised by the movement of the work or lapping tool for double side lapping
    • 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
    • B24B37/07—Lapping machines or devices; Accessories designed for working plane surfaces characterised by the movement of the work or lapping tool
    • B24B37/10—Lapping machines or devices; Accessories designed for working plane surfaces characterised by the movement of the work or lapping tool for single side lapping
    • B24B37/105—Lapping machines or devices; Accessories designed for working plane surfaces characterised by the movement of the work or lapping tool for single side lapping the workpieces or work carriers being actively moved by a drive, e.g. in a combined rotary and translatory movement
    • 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
    • B24B7/00—Machines or devices designed for grinding plane surfaces on work, including polishing plane glass surfaces; Accessories therefor
    • B24B7/20—Machines or devices designed for grinding plane surfaces on work, including polishing plane glass surfaces; Accessories therefor characterised by a special design with respect to properties of the material of non-metallic articles to be ground
    • B24B7/22—Machines or devices designed for grinding plane surfaces on work, including polishing plane glass surfaces; Accessories therefor characterised by a special design with respect to properties of the material of non-metallic articles to be ground for grinding inorganic material, e.g. stone, ceramics, porcelain
    • B24B7/228—Machines or devices designed for grinding plane surfaces on work, including polishing plane glass surfaces; Accessories therefor characterised by a special design with respect to properties of the material of non-metallic articles to be ground for grinding inorganic material, e.g. stone, ceramics, porcelain for grinding thin, brittle parts, e.g. semiconductors, wafers
    • C—CHEMISTRY; METALLURGY
    • C30—CRYSTAL GROWTH
    • C30B—SINGLE-CRYSTAL GROWTH; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL OR UNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL; REFINING BY ZONE-MELTING OF MATERIAL; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR
    • C30B33/00—After-treatment of single crystals or homogeneous polycrystalline material with defined structure
    • 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
    • H01L21/02013—Grinding, lapping

Definitions

  • the present invention relates to a method for producing a polished-article.
  • the present inventors found that the machining quality in the grinding step could be further improved and the total processing time in the grinding and polishing steps could be further shortened by considering the processing time in total and reviewing working in the grinding step, and achieved the present invention.
  • a method for producing a polished-article of the present invention is a method that produces a polished article by polishing an object to be polished, the method for producing a polished-article including a grinding step of grinding a surface of the object to be polished with a grinding wheel rotating at a peripheral speed of 10 m/s or less.
  • the producing method for the polished-article according to the present invention can further improve machining quality in the grinding step and can further shorten the processing time in the grinding and polishing steps. This is because, in the grinding step, the occurrence of strain, a damaged layer, a microcrack, or the like due to machining can be further suppressed by performing low-speed grinding that was not performed before. As a result, the processing time in the grinding step is lengthened, but the time required for the polishing step after the grinding step can be greatly shortened. Thus, the processing time in the grinding and polishing steps can be shortened.
  • FIG. 1 is a flowchart showing an example of a substrate machining process.
  • FIG. 2 is a schematic structural view illustrating an example of a configuration of a grinding apparatus 10 according to an embodiment.
  • FIG. 3 is a schematic structural view illustrating an example of a structure of a lapping device 20 according to the embodiment.
  • FIG. 4 is a schematic structural view illustrating an example of a structure of a CMP device 30 according to the embodiment.
  • FIG. 5 shows images of surfaces after grinding in Example 1 and Comparative Example 1.
  • FIG. 1 is a flowchart showing an example of a substrate machining process according to an embodiment of the present invention.
  • FIG. 2 is a schematic structural view illustrating an example of a configuration of a grinding apparatus 10 according to the embodiment.
  • FIG. 3 is a schematic structural view illustrating an example of a structure of a lapping device 20 according to the embodiment.
  • FIG. 4 is a schematic structural view illustrating an example of a structure of a CMP (chemical mechanical polishing) device 30 according to the present invention.
  • CMP chemical mechanical polishing
  • a method for producing a polished-article includes a cutting step of obtaining a disc-shaped object to be polished by cutting a columnar ingot (Step S 100 ), a grinding step of grinding the object to be polished obtained by cutting (Step S 110 ), a lapping step of polishing the ground object to be polished (Step S 120 ), a CMP step of further performing in tandem with chemical treatment (Step S 130 ), and a cleaning step of performing surface cleaning (Step S 140 ), and obtains a polished article subjected to polishing.
  • the grinding step, the lapping step, and the CMP step will be described mainly.
  • the lapping step and the CMP step may be omitted, or a step other than these steps, such as a polishing step, may be added appropriately.
  • an object to be polished 18 includes various kinds of semiconductor wafers and single crystal wafers, and contains silicon, silicon oxide, alumina, sapphire, or silicon carbide, or a compound semiconductor such as gallium nitride, gallium phosphate, gallium arsenide, indium phosphide, lithium niobate, or lithium tantalate.
  • an object to be polished 18 (substrate) is ground with a grinding apparatus 10 illustrated in FIG. 2 .
  • the grinding apparatus 10 includes a controller 11 for controlling the entire apparatus, a grinding motor 14 , a base metal 15 to be rotated by the grinding motor 14 , and a grinding wheel 16 fixed to the base metal 15 .
  • a grinding mechanism 12 of the grinding apparatus 10 is configured as a mechanism that carries out infeed machining for grinding the object to be polished 18 with the grinding wheel 16 while axially rotating the grinding wheel 16 and axially rotating the object to be polished 18 fixed to an unillustrated fixing plate.
  • the grinding apparatus 10 is provided with the grinding motor 14 that can output sufficient torque when the grinding wheel 16 rotates in a low-speed rotation range, for example, a rotation speed range higher than or equal to 10 rpm and less than 2000 rpm.
  • the controller 11 controls driving of the grinding motor 14 so that the grinding motor 14 rotates at a predetermined number of rotations.
  • a surface 19 of the object to be polished 18 is ground with the grinding wheel 16 that rotates at a peripheral speed of 10 m/s or less. This can further improve machining quality in the grinding step and can further shorten the processing time in the grinding and polishing steps.
  • the surface 19 of the object to be polished 18 is preferably ground with the grinding wheel 16 that rotates at a peripheral speed of 0.5 m/s or more. This is preferable because lengthening of the time in the grinding step can be further suppressed and the processing time in the grinding and polishing steps can be further shortened.
  • the number of rotations of the grinding wheel 16 is preferably 1000 rpm or less, and more preferably 800 rpm or less.
  • the cut amount in the grinding step can be appropriately set according to the peripheral speed of the grinding wheel 16 , and for example, the cut amount is preferably within the range of 0.1 to 50 ⁇ m/min, more preferably within the range of 0.5 to 40 ⁇ m/min, and further preferably within the range of 1 to 30 ⁇ m/min.
  • the grinding step is generally performed while the grain cut depth is smaller than a critical cut depth Dc.
  • This critical cut depth Dc refers to the cut amount at a transition point in a deformation process from a brittle mode to a ductile mode in ductile mode machining of a hard brittle material.
  • the grain cut depth is inversely proportional to the peripheral speed (that is, number of rotations) of the grinding wheel. To decrease the grain cut depth, it is necessary to increase the peripheral speed of the grinding wheel. However, when the peripheral speed of the grinding wheel is increased, the load on the abrasive grains decreases, and the abrasive grains become susceptible to abrasion and wear.
  • abrasion and wear of the abrasive grains are so small that they cause no problem for general materials, they become heavy particularly for a high-hardness material. This sometimes deteriorates the machining quality.
  • abrasion and wear of the abrasive grains are further suppressed by further decreasing the peripheral speed of the grinding wheel.
  • the grinding wheel 16 used in the grinding step can be formed by compacting abrasive grains of oxide, carbide, nitride, and diamond.
  • the grinding wheel 16 are a vitrified bonded wheel to be fired at high temperature by using clay, such as feldspar, as the binder, a metal bonded wheel fixed by metal, and a resin bonded wheel to be fired at low temperature by using a synthetic resin of phenol, formalin, or the like. Since the grinding wheel 16 is rotated at low peripheral speed, which was not adopted before, in the grinding apparatus 10 , the hardness, porosity, and so on thereof are appropriately adjusted.
  • the grinding wheel 16 may be an electrodeposited grain wheel in which abrasive grains are fixed by a plating layer.
  • the object to be polished 18 is lapped with a lapping device 20 illustrated in FIG. 3 .
  • the lapping device includes an upper surface plate 22 , a rotatable lower surface plate 23 disposed opposed to the upper surface plate 22 , and disc-shaped carriers 24 to be clamped between these laps.
  • the object to be polished 18 is placed on lower surfaces of the carriers 24 .
  • the object to be polished 18 is clamped by the upper surface plate 22 and the lower surface plate 23 , and is polished with abrasive grains to increase flatness.
  • the object to be polished 18 is chemically and mechanically polished with a CMP device 30 illustrated in FIG. 4 .
  • the CMP device 30 includes a surface plate 32 , a polishing head 33 , and a slurry supply device 34 .
  • a polishing pad 40 is attached to the surface plate 32 .
  • Slurry is supplied from the slurry supply device 34 onto the polishing pad 40 , and the surface plate 32 rotates.
  • the polishing head 33 rotates in the same direction as the surface plate 32 while pressing the object to be polished 18 placed on the polishing pad 40 against the polishing pad 40 , and thereby chemically and mechanically polishes the surface 19 of the object to be polished 18 .
  • the slurry is supplied from the slurry supply device 34 of the CMP device 30 onto a surface of the polishing pad 40 .
  • the slurry contains an abrasive material, an acid, an oxidant, a surfactant, and water.
  • abrasive material for example, colloidal silica, fumed silica, alumina, titania, zirconia, diamond, and a mixture of these materials can be used.
  • As the oxidant for example, peroxide and nitrate can be used.
  • the slurry may further contain a pH adjuster.
  • the pH adjuster appropriately uses an acid substance or a basic substance in order to adjust the pH value of the slurry to a desired value.
  • the machining quality in the grinding step can be further improved, and the processing time in the grinding and polishing steps can be further shortened.
  • the processing time in the grinding and polishing steps can be further shortened.
  • the present invention is not limited to the above-described embodiment, and can be carried out by various modes as long as they belong to the technical scope of the invention.
  • the grinding apparatus was produced by using a grinding motor that generated sufficient torque (for example 20 to 60 N ⁇ m) when a grinding wheel was rotated at a peripheral speed of 10 m/s or less and using a controller that rotated the grinding motor at the peripheral speed of 10 m/s or less.
  • a single crystal wafer of high-purity alumina was prepared, and a grinding step was performed by the grinding apparatus illustrated in FIG. 2 .
  • a grinding wheel having a diameter of 150 cm was used and rotated at a peripheral speed of 10 m/s (number of rotations of 1000 rpm) to grind the alumina wafer serving as an object to be polished. At this time, the cut amount was 30 ⁇ m/min.
  • a vitrified bonded wheel mainly composed of glass was used as the grinding wheel.
  • the above-described ground wafer was subjected to lapping.
  • Lapping was performed for three hours by using the lapping device 20 illustrated in FIG. 3 while the number of rotations of the upper surface plate was set at 60 rpm, the number of rotations of the lower surface plate was set at 60 rpm, and abrasive grains of diamond were used.
  • Comparative Example 1 an operation similar to that of Example 1 was performed except that the grinding wheel was rotated at a peripheral speed of 15 m/s (number of rotations of 1500 rpm), the cut amount was 60 ⁇ m/min, and the lapping time was nine hours.
  • Example 2 operations similar to that of Example 1 were performed except that an object to be polished was a sapphire wafer and a GaN wafer, respectively.
  • Comparative Examples 2 and 3 operations similar to that of Comparative Example 1 were performed except that an object to be polished was a sapphire wafer and a GaN wafer, respectively.
  • the surface roughnesses Ra in Examples 1 to 3 and Comparative Example 1 were measured. The measurement was taken in conformity with JIS-B0601-2001.
  • FIG. 5 shows images of surfaces after grinding in Example 1 and Comparative Example 1.
  • the surface roughness Ra after grinding was 0.5 ⁇ m in Comparative Example 1, whereas it was 0.1 ⁇ m in Example 1.
  • the surface roughness was improved.
  • the total time required until the completion of the grinding and lapping steps was 9.5 hours in Comparative Example 1, whereas it was 4.0 hours in Example 1.
  • the total processing time was shortened in Example 1.
  • the polishing method for the object to be polished according to the present invention can be used to polish a surface of an object to be polished such as a semiconductor wafer.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Chemical & Material Sciences (AREA)
  • Ceramic Engineering (AREA)
  • Inorganic Chemistry (AREA)
  • Manufacturing & Machinery (AREA)
  • Power Engineering (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Computer Hardware Design (AREA)
  • Physics & Mathematics (AREA)
  • Condensed Matter Physics & Semiconductors (AREA)
  • General Physics & Mathematics (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Organic Chemistry (AREA)
  • Metallurgy (AREA)
  • Materials Engineering (AREA)
  • Mechanical Treatment Of Semiconductor (AREA)
  • Grinding Of Cylindrical And Plane Surfaces (AREA)
  • Finish Polishing, Edge Sharpening, And Grinding By Specific Grinding Devices (AREA)
US14/722,222 2013-10-02 2015-05-27 Method for producing polished-article Abandoned US20150266155A1 (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
JP2013206888 2013-10-02
JP2013-206888 2013-10-02
PCT/JP2014/076433 WO2015050218A1 (ja) 2013-10-02 2014-10-02 研磨物の製造方法

Related Parent Applications (1)

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PCT/JP2014/076433 Continuation WO2015050218A1 (ja) 2013-10-02 2014-10-02 研磨物の製造方法

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US (1) US20150266155A1 (zh)
JP (1) JPWO2015050218A1 (zh)
KR (1) KR20150073214A (zh)
CN (1) CN104822491A (zh)
WO (1) WO2015050218A1 (zh)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US11623319B2 (en) * 2015-08-14 2023-04-11 Ii-Vi Delaware, Inc. Machine for finishing a work piece, and having a highly controllable treatment tool

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109202593A (zh) * 2018-10-09 2019-01-15 德淮半导体有限公司 晶圆修剪刀片
CN112743447B (zh) * 2020-12-31 2022-04-15 泉芯集成电路制造(济南)有限公司 一种转轴角度确认机构及硅片研磨装置
WO2023277103A1 (ja) * 2021-06-30 2023-01-05 京セラ株式会社 周期表第１３族元素窒化物結晶基板の製造方法

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JPS63200953A (ja) * 1987-02-17 1988-08-19 Kiyoshi Suzuki 超音波加工用アタツチメント
JPH0714582B2 (ja) * 1991-04-19 1995-02-22 工業技術院長 セラミックス表面の残留応力制御研削方法
US6206764B1 (en) * 1997-04-17 2001-03-27 The United States Of America As Represented By The Secretary Of Commerce Methods for machining hard materials using alcohols
US6679758B2 (en) * 2002-04-11 2004-01-20 Saint-Gobain Abrasives Technology Company Porous abrasive articles with agglomerated abrasives
JP4130614B2 (ja) * 2003-06-18 2008-08-06 株式会社東芝 半導体装置の製造方法
TWI286963B (en) * 2004-03-10 2007-09-21 Read Co Ltd Dresser for polishing cloth and method for manufacturing thereof
JP2005271160A (ja) 2004-03-25 2005-10-06 Noritake Co Ltd 平面研削加工用砥石
JP5494552B2 (ja) * 2011-04-15 2014-05-14 信越半導体株式会社 両頭研削方法及び両頭研削装置
WO2013038573A1 (ja) * 2011-09-15 2013-03-21 新東工業株式会社 硬脆性材料の研削・研磨加工システム、および研削・研磨方法

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US11623319B2 (en) * 2015-08-14 2023-04-11 Ii-Vi Delaware, Inc. Machine for finishing a work piece, and having a highly controllable treatment tool

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JPWO2015050218A1 (ja) 2017-03-09
WO2015050218A1 (ja) 2015-04-09
CN104822491A (zh) 2015-08-05
KR20150073214A (ko) 2015-06-30

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