EP0798078A2 - Verfahren und Vorrichtung zum Herstellen von Stützunterlagen - Google Patents

Verfahren und Vorrichtung zum Herstellen von Stützunterlagen Download PDF

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Publication number
EP0798078A2
EP0798078A2 EP97302066A EP97302066A EP0798078A2 EP 0798078 A2 EP0798078 A2 EP 0798078A2 EP 97302066 A EP97302066 A EP 97302066A EP 97302066 A EP97302066 A EP 97302066A EP 0798078 A2 EP0798078 A2 EP 0798078A2
Authority
EP
European Patent Office
Prior art keywords
sheeted
backing pad
elastic member
manufacturing
round flanges
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Withdrawn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
EP97302066A
Other languages
English (en)
French (fr)
Other versions
EP0798078A3 (de
Inventor
Hiromasa Hashimoto
Koichi Saito
Koji Morita
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.)
Shin Etsu Handotai Co Ltd
Original Assignee
Shin Etsu Handotai Co 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
Application filed by Shin Etsu Handotai Co Ltd filed Critical Shin Etsu Handotai Co Ltd
Publication of EP0798078A2 publication Critical patent/EP0798078A2/de
Publication of EP0798078A3 publication Critical patent/EP0798078A3/de
Withdrawn legal-status Critical Current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
    • B24B37/00—Lapping machines or devices; Accessories
    • B24B37/11—Lapping tools
    • B24B37/20—Lapping pads for working plane surfaces
    • B24B37/26—Lapping pads for working plane surfaces characterised by the shape of the lapping pad surface, e.g. grooved
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B24—GRINDING; POLISHING
    • B24D—TOOLS FOR GRINDING, BUFFING OR SHARPENING
    • B24D11/00—Constructional features of flexible abrasive materials; Special features in the manufacture of such materials
    • B24D11/02—Backings, e.g. foils, webs, mesh fabrics
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B24—GRINDING; POLISHING
    • B24D—TOOLS FOR GRINDING, BUFFING OR SHARPENING
    • B24D18/00—Manufacture of grinding tools or other grinding devices, e.g. wheels, not otherwise provided for

Definitions

  • the present invention relates to a method for manufacturing backing pad suitable for polishing semiconductor wafers by the waxless method and a manufacturing apparatus, in particular to a method and an apparatus for carving a number of grooves on a wafer holding surface of a sheeted elastic member.
  • Semiconductor wafers are mirror-polished generally in their finishing process by so-called chemical mechanical polishing process.
  • Most popular methods for supporting the wafers onto polishing carriers in this mirror polishing include the wax process and the waxless process, in which the former process involves the use of adhesion wax spread on one surface thereof, and the latter process involves either the use of vacuum chuck or water-aided holdihng on a backing pad made of porous resin such as polyurethane foam material.
  • a polishing apparatus 51 used in the waxless process based on water-aided holding comprises a polishing load 52, a template 53, a polishing pad 54 and a turn table 55.
  • the template 53 further consists of a polishing plate 56, backing pad 57 and a template blank 58, all of which layered in this order.
  • the polishing plate 56 is formed as a round ceramic plate.
  • the backing pad 57 is made of polyurethane foam material having a flat and smooth bottom surface (facing to the table side) provided as a wafer holding surface 37a and a porous content with a great number of isolated pores.
  • the template blank 58 is referred as a laminated glass fiber plate immersed, for example, with epoxy resin, and has engagement holes 58a bored therein for holding a wafer.
  • the backing pad 57 is fixed on the polishing plate 56, the template blank 58 fixed on the backing pad 57, and the polishing pad 34 fixed on the turn table 55, respectively, using adhesive.
  • a semiconductor wafer W is fixed on the template 53 according to the procedures given below.
  • the semiconductor wafer W is, as shown in Fig.5, adsorbed and fixed on the wafer holding surface 57a of the backing pad 57 assisted by surface tension of the water.
  • the above gap might trap the air and 61 as shown in Fig.6, thus allowing the wafer W to be polished as convexed toward the polishing pad 54, which would result in nonuniform thickness in the polishing stock removal 62.
  • the polished surface Wa of the wafer W would be concaved in its center since the center portion is polished excessively as compared with the peripheral portion, which has been pointed out as a demerit.
  • the above object is attained by providing a method for manufacturing a backing pad used for fixing semiconductor wafer to be polished based on the waxless method and having a number of grooves on the wafer holding surface of the sheeted elastic member, in which the grooves are formed by using a groove forming member having a plurality of round flanges with almost equal diameters (or the same diameter) arrayed at proper intervals along and concentrically with an axial body, heating the round flanges of the groove forming member to a temperature higher than the softening point of the sheeted elastic member , traveling the member over the surface of the sheeted elastic member to make the flanges roll under pressure on the sheeted elastic member, which results in simultaneous formation of a plurality of grooves having a shape and a size corresponded to the outer edge of the round flanges.
  • backing pad enables automatic and quick discharge, upon wafer loading, of the air and the excessive water once trapped in a gap between the wafer holding surface of the backing pad and the wafer back when a semiconductor wafer is fixed on the backing pad with aid of surface tension of water.
  • a backing pad manufacturing apparatus comprising a fixing member made of sheeted elastic material, and a groove forming unit having a plurality of metallic round flanges with an almost equal diameters arrayed at proper intervals along and concentrically with an axial body, the axial body being rotatable as well as reciprocative in the direction parallel to a sheeted elastic material fixing plane of the fixing member, and the plural number of round flanges are heatable to a temperature higher than the softening point of the sheeted elastic member.
  • Fig.1 shows a front view for explaining a backing pad manufacturing apparatus of the present invention
  • Fig.2 is a right side view of Fig.1.
  • a vacuum chuck table 4 rotatable at a 90° pitch with aid of a drive unit 3 equipped with a motor 2.
  • a top surface of the chuck table 4 is perforated with a number of vacuum suction holes (not shown), the holes being communicated to the suction side of a vacuum pump (not shown).
  • the top surface of the chuck table 4 is aligned in the horizontal direction.
  • a load/unload conveyer 11 On the upper part of the base frame 1, are equipped a load/unload conveyer 11 and a groove forming unit 21 for carving a number of straight grooves on the wafer holding surface of the sheeted elastic member.
  • a timing belt (not shown) is wound around a grooved pulley 5 driven by the motor 2 and a grooved pulley 7 connected to a rotation axis.
  • the load/unload conveyer 11 comprises a metal plate 14 reciprocated (in the lateral direction in Fig.1) by an air cylinder 12 and a metal plate 15 reciprocated by an air cylinder 13, both of which aligned in a rightly opposing manner in a horizontal plane to enable adjustment of gap between these metal plates 14 and 15.
  • the front edge faces (opposing faces) of the metal plates 14 and 15 are concaved in an arc form in a flat view, so that a nearly round through hole appears when the gap is minimized.
  • the groove forming unit 21 comprises a frame 24 having wheels 24a in its bottom part, a main body 22 mounted on the lower part of the frame 24, and a friction roller 23 made of heat-resistant rubber and mounted on the upper part of the frame 24, so that the frame 24 is reciprocated (in the lateral direction in Fig.2) by a drive unit (not shown) along a straight rail 25 extended in a horizontal direction.
  • the main body 22 comprises an aluminum-made hollow axis 26 supported by the frame 24 in a freely rotatable manner, and a plurality of aluminum-made round flanges 27 immobilized on the hollow axis 26.
  • round flanges 27 having an equal diameter are aligned concentrically and orthogonally to the hollow axis 26, with the intervals between adjacent outer edges of the round flanges 27 kept constant.
  • the friction roller 23 is supported on the frame 24 in a freely rotatable manner, and can contact its peripheral face with all of the round flanges 27 with pressure resulted from its own weight, by which residue of the sheeted elastic member adhered on the circumference of the round flanges 27 can be removed.
  • the gap between the outer edge face of the round flanges 27 and top surface (vacuum chuck plane) of the chuck table 4 need be fine-adjustable, thus the design involves fine adjustment of a fixation height of the rotation axis of the hollow axis 26.
  • the hollow axis 26 is designed to accomodate a heat medium, for example, steam flow at a proper temperature, or to have a heater.
  • a heat medium for example, steam flow at a proper temperature
  • the round flanges 27 are brought into rolling contact with the sheeted elastic member and allowed to rotate like an idle wheel.
  • the hollow axis 26 of the main body 22 was supplied with steam to raise its temperature equals to the softening point of the sheeted elastic member or above (melting point, for example).
  • the friction roller 23 was then placed by its own weight on the outer periphery of the round flanges 27, and the frame 24, or substantially the groove forming unit 21, is traveled on the straight rail 25 from the starting position to the ending position.
  • the round flanges 27 are thus rolled while being kept in pressure-contact on the wafer holding surface of the sheeted elastic member. Since the wafer holding surface brought into contact with the outer periphery of the round flanges 27 is locally heated to be softened as well as pressed, a plurality of straight grooves having a width almost equals to that for the outer periphery of the round flange 27 are formed at a time, while generating an intergroove pitch almost same as the interval between adjacent outer edges of the round flanges 27.
  • Fig.2 shows a status in which the groove forming unit 21 is rested on the starting position of the rail 25.
  • the chuck table 4 is then rotated at 90° , while the rotation of the chuck table 4 being not interfered since the groove forming unit 21 being rested on the end position of the rail 25, and the forming unit 21 is traveled again from the end position to the starting position.
  • a backing pad is successfully obtained, in which the wafer holding surface 30a of the sheeted member 30 is smoothly finished and thereon a number of grooves 32 are carved in a lattice form,
  • All the grooves 32 run straight toward the outer periphery of the sheeted elastic member 30 and have an equal width and an equal depth, both values being kept in constant along the longitudinal direction of the grooves 32.
  • An intergroove pitch is also kept in constant over the entire of the wafer holding surface 30a.
  • the backing pad 31 is, as indicated for example by two-dot chain line in Fig.3, formed in a diameter as large enough to afford a plurality of wafers W, W .... (five slices in Fig.3 for example).
  • known materials including the above-mentioned polyurethane foam material are available (see the descriptions below).
  • a most preferable layout of the groove 32 is referred as a square lattice, but an oblique lattice and parallel linear (stripe) pattern are also allowable by request.
  • stripe pattern it is not necessary to rotate the chuck table 4.
  • the groove forming unit 21 is traveled along the rail 25 from its starting position to the end, the chuck table is then rotated at an arbitrary angle, and again the groove forming unit 21 is traveled along the rail 25 from its starting position to the end position.
  • the backing pad 31 does not absolutely require that all the grooves 32 run throughout the edge of the sheeted elastic member 30 as described above, but only require that all or nearly all of the grooves 32 reach at least the edge of the wafers.
  • the grooves 32 are thus not necessarily be formed in geometrically straight but waviness to some degree is also permissible.
  • the thickness of the backing pad 31, as well as the depth, width and intergroove pitch of the grooves 32 can properly be set considering mainly diameter of semiconductor wafer.
  • a typical fabrication process of the sheeted elastic member 30 is as the following.
  • a commercial uniform-thick elastic sheet made of polyurethane foam material having internally a great number of isolated pores is employed, one surface of which is designated as a wafer holding surface (more correctly a surface functions as a wafer holding surface after fabricated into a backing pad), the wafer holding surface is ground into flat with a surface grinder, and the sheet is cut into a round plate with a predetermined diameter. The round plate is then fixed on a ceramics-made polishing plate with an adhesive, and smoothened on its wafer holding surface using a precision surface grinder (product of Shibayama Kikai Co., Ltd.).
  • a precision surface grinder product of Shibayama Kikai Co., Ltd.
  • the air and the excessive water once trapped into a gap between the wafer holding surface 1a of the backing pad 31 and the back surface of each wafer W are automatically routed to the groove 2 and discharged from the edge of the wafers W.
  • This allows the polished surface Wa of the wafer W kept during the process in parallel with the polishing surface of the polishing pad 34, which will, without difficulty, result in an uniform thickness of a polishing stock removal 33 and an advanced flatness in the polished surface of the wafer W even when large-sized wafers are used.
  • a backing pad of the present invention In a manufacturing process of a backing pad of the present invention, as shown in Fig.3 or as described later in [Test Example 1], diameter or other specifications of a single backing pad is so set to afford a plurality of wafers at the same time.
  • a template blank bored with a plurality of round through holes are fixed on the polishing plate and the backing pad is fixed thereon by insertion into these through holes, so that each backing pad can hold a single semiconductor wafer.
  • the round backing pad made of polyurethane foam material as fabricated in the first embodiment and as shown in Fig.3 was used. It was 565 mm diameter, 0.3 mm thick and having a pore size of 10 to 30 ⁇ m.
  • the groove 32 aligned on the wafer holding surface of the backing pad in a lattice pattern had a width of 0.5 mm, an intergroove pitch of 15 mm and a depth of 0.3 mm, each value being kept constant over the entire of the wafer holding surface, and its width and depth also kept unchanged within the longitudinal direction.
  • the round plate backing pad 31 was fixed on a ceramic polishing plate 56 having a nearly equal diameter using an adhesive, on which the glass fiber reinforced epoxy resin-made template blank 58 having five engagement holes aligned on a single circumference for fixing wafers was fixed also with the adhesive.
  • a surface area within which the round through holes are exposed can thus serve as a wafer holding surface.
  • the wafer holding surface 30a of the backing pad 31 was then applied with water, removed therefrom with an excessive water, and pressed thereto with the back surface of a wafer in such a manner that the wafer center being supported.
  • the silicon wafer W was adherently fixed onto the backing pad 31 with aid of surface tension of water, while some air and excessive water trapped between the wafer holding surface 30a and the back surface of the wafer were automatically and quickly discharged out of the backing pad 31 through the grooves 32.
  • the polished surface Wa was thus maintained in parallel with the polishing surface of the polishing pad 54 as shown in Fig.4.
  • the polishing load 52 was descended so that the polished surface Wa of the silicon wafer W is brought into contact and pressed with the polishing pad 54 at an predetermined pressure.
  • the polishing load 52 was allowed to rotate as well as revolve, and the turn table 55 was rotated in the counter direction as that for the rotation of the polishing load 52, to effect a simultaneous mirror polishing of five slices of silicon wafers.
  • LTVmax Flatness of the polished surfaces of the wafers were evaluated in terms of LTVmax (in ⁇ m).
  • LTVmax is defined as a maximum difference between a maximum value and a minimum value of thickness observed in a 20 mm ⁇ 20 mm cell divided from a wafer, that is a maximum value of LTV (Local Thickness Variation). Results of the measurement using a general thickness gauge were shown in Table 1.
  • Comparative Example 1 has a larger variation in LTVmax among the wafers as well as a larger average value of LTVmax.
  • LTVmax was less variable and gave a smaller average value. It was also confirmed that the entire surface of the wafers were polished with an advanced flatness in Example 1, whereas the wafers were concaved in their centers in Comparative Example 1.
  • batch polishing silictaneous multi-wafer polishing
  • a backing pad obtained by a manufacturing method and using a manufacturing apparatus of the present invention can provide mirror-polished wafers with an advanced flatness and a good uniformity in the flatness among the wafers without difficulties.
  • a manufacturing method and manufacturing apparatus of the present invention employ a groove forming member having a plurality of round flanges arrayed in parallel along an axial body, and make the flanges roll under pressure on the wafer holding surface, while the flanges being heated to a temperature higher than a softening point of the plastic-made sheeted elastic member.
  • a backing pad having a number of grooves on the wafer holding surface of the sheeted elastic member is obtained.
  • the air and excessive water once trapped into gaps between the wafer holding surface of the backing pad and wafer backs are routed to the grooves to be discharged from behind the wafers in an automatic and quick manner. Since the polished surface of the wafers are thus supported in parallel to the polishing surface of the polishing pad during the polishing process and polishing allowance is made into an uniform thickness, it is facilitated to obtain an advanced flatness of the mirror-polished surface of the wafers.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Manufacturing & Machinery (AREA)
  • Finish Polishing, Edge Sharpening, And Grinding By Specific Grinding Devices (AREA)
  • Polishing Bodies And Polishing Tools (AREA)
  • Mechanical Treatment Of Semiconductor (AREA)
EP97302066A 1996-03-28 1997-03-26 Verfahren und Vorrichtung zum Herstellen von Stützunterlagen Withdrawn EP0798078A3 (de)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP10437196A JPH09262763A (ja) 1996-03-28 1996-03-28 バッキングパッドの製造方法および装置
JP104371/96 1996-03-28

Publications (2)

Publication Number Publication Date
EP0798078A2 true EP0798078A2 (de) 1997-10-01
EP0798078A3 EP0798078A3 (de) 1998-04-08

Family

ID=14378943

Family Applications (1)

Application Number Title Priority Date Filing Date
EP97302066A Withdrawn EP0798078A3 (de) 1996-03-28 1997-03-26 Verfahren und Vorrichtung zum Herstellen von Stützunterlagen

Country Status (3)

Country Link
EP (1) EP0798078A3 (de)
JP (1) JPH09262763A (de)
TW (1) TW348280B (de)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1298714A1 (de) * 2001-03-06 2003-04-02 Sumitomo Electric Industries, Ltd. Verfahren zur herstellung eines zusammengesetzten halbleiter-wafers
CN109605179A (zh) * 2019-01-14 2019-04-12 桃江冰梦家居用品有限公司 一种凉席竹片无轴抛光设备及其使用方法
CN114523410A (zh) * 2022-03-11 2022-05-24 南京林业大学 一种智能的家具抛光打蜡一体化设备
CN115056045A (zh) * 2022-06-30 2022-09-16 成都泰美克晶体技术有限公司 一种晶圆单面抛光装置及方法
CN115609392A (zh) * 2022-09-29 2023-01-17 亚新半导体科技(无锡)有限公司 一种Fab厂用具有智能化自动抓取功能的加工设备

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP4520327B2 (ja) * 2004-03-31 2010-08-04 不二越機械工業株式会社 吸水方法及び吸水装置
JP6696756B2 (ja) * 2014-11-13 2020-05-20 富士紡ホールディングス株式会社 保持具及びその製造方法
JP2020188057A (ja) * 2019-05-10 2020-11-19 株式会社ディスコ 固定方法及び樹脂シート
CN112454188A (zh) * 2020-12-14 2021-03-09 重庆希尔亿朋轨道交通设备有限公司 一种轨道打磨砂轮加工设备

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2007388A1 (en) * 1970-02-18 1971-09-02 Spies W Patterning plastic foam panel
FR2662971A1 (fr) * 1990-06-08 1991-12-13 Loire Snc Literie Mousses Val Procede de fabrication d'objets en mousse revetue de tissu et moule pour la mise en óoeuvre de ce procede.

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6099561A (ja) * 1984-10-01 1985-06-03 Yoshiaki Nagaura 精密加工法

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2007388A1 (en) * 1970-02-18 1971-09-02 Spies W Patterning plastic foam panel
FR2662971A1 (fr) * 1990-06-08 1991-12-13 Loire Snc Literie Mousses Val Procede de fabrication d'objets en mousse revetue de tissu et moule pour la mise en óoeuvre de ce procede.

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
PATENT ABSTRACTS OF JAPAN vol. 009, no. 249 (M-419), 5 October 1985 & JP 60 099561 A (YOSHIAKI NAGAURA), 3 June 1985, *

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1298714A1 (de) * 2001-03-06 2003-04-02 Sumitomo Electric Industries, Ltd. Verfahren zur herstellung eines zusammengesetzten halbleiter-wafers
EP1298714A4 (de) * 2001-03-06 2006-05-24 Sumitomo Electric Industries Verfahren zur herstellung eines zusammengesetzten halbleiter-wafers
CN109605179A (zh) * 2019-01-14 2019-04-12 桃江冰梦家居用品有限公司 一种凉席竹片无轴抛光设备及其使用方法
CN114523410A (zh) * 2022-03-11 2022-05-24 南京林业大学 一种智能的家具抛光打蜡一体化设备
CN115056045A (zh) * 2022-06-30 2022-09-16 成都泰美克晶体技术有限公司 一种晶圆单面抛光装置及方法
CN115056045B (zh) * 2022-06-30 2023-10-20 成都泰美克晶体技术有限公司 一种晶圆单面抛光装置及方法
CN115609392A (zh) * 2022-09-29 2023-01-17 亚新半导体科技(无锡)有限公司 一种Fab厂用具有智能化自动抓取功能的加工设备

Also Published As

Publication number Publication date
TW348280B (en) 1998-12-21
EP0798078A3 (de) 1998-04-08
JPH09262763A (ja) 1997-10-07

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