WO2017159213A1 - 両面研磨装置用のキャリアの製造方法およびウェーハの両面研磨方法 - Google Patents
両面研磨装置用のキャリアの製造方法およびウェーハの両面研磨方法 Download PDFInfo
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- WO2017159213A1 WO2017159213A1 PCT/JP2017/005950 JP2017005950W WO2017159213A1 WO 2017159213 A1 WO2017159213 A1 WO 2017159213A1 JP 2017005950 W JP2017005950 W JP 2017005950W WO 2017159213 A1 WO2017159213 A1 WO 2017159213A1
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- carrier
- polishing
- surface plate
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- wafer
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- 238000005498 polishing Methods 0.000 title claims abstract description 146
- 238000000034 method Methods 0.000 title claims abstract description 38
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 27
- 230000009977 dual effect Effects 0.000 title abstract 3
- 239000000463 material Substances 0.000 claims abstract description 134
- 230000000630 rising effect Effects 0.000 claims description 50
- 238000005259 measurement Methods 0.000 claims description 25
- 230000002093 peripheral effect Effects 0.000 claims description 11
- 239000004744 fabric Substances 0.000 claims description 10
- 238000002360 preparation method Methods 0.000 claims description 5
- 239000006061 abrasive grain Substances 0.000 claims description 4
- 239000007864 aqueous solution Substances 0.000 claims description 4
- 239000000969 carrier Substances 0.000 claims description 4
- 239000002904 solvent Substances 0.000 claims description 4
- 238000007865 diluting Methods 0.000 claims 1
- 238000003780 insertion Methods 0.000 abstract 5
- 230000037431 insertion Effects 0.000 abstract 5
- 235000012431 wafers Nutrition 0.000 description 55
- 230000000052 comparative effect Effects 0.000 description 15
- 239000002002 slurry Substances 0.000 description 6
- 238000007517 polishing process Methods 0.000 description 5
- 230000000694 effects Effects 0.000 description 4
- 229920005989 resin Polymers 0.000 description 4
- 239000011347 resin Substances 0.000 description 4
- JOYRKODLDBILNP-UHFFFAOYSA-N Ethyl urethane Chemical compound CCOC(N)=O JOYRKODLDBILNP-UHFFFAOYSA-N 0.000 description 3
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 3
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 description 3
- 229910052751 metal Inorganic materials 0.000 description 3
- 239000002184 metal Substances 0.000 description 3
- 239000010936 titanium Substances 0.000 description 3
- 229910052719 titanium Inorganic materials 0.000 description 3
- 239000003795 chemical substances by application Substances 0.000 description 2
- 239000011248 coating agent Substances 0.000 description 2
- 238000000576 coating method Methods 0.000 description 2
- 239000002245 particle Substances 0.000 description 2
- 229910001220 stainless steel Inorganic materials 0.000 description 2
- 239000010935 stainless steel Substances 0.000 description 2
- 239000004593 Epoxy Substances 0.000 description 1
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 1
- 239000003082 abrasive agent Substances 0.000 description 1
- 239000012670 alkaline solution Substances 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
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- 238000001035 drying Methods 0.000 description 1
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- 239000011521 glass Substances 0.000 description 1
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- 239000000377 silicon dioxide Substances 0.000 description 1
Images
Classifications
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- 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
- B24B27/00—Other grinding machines or devices
- B24B27/0076—Other grinding machines or devices grinding machines comprising two or more grinding tools
-
- 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
-
- 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
- B24B37/27—Work carriers
- B24B37/28—Work carriers for double side lapping of plane surfaces
-
- 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
- B24B7/10—Single-purpose machines or devices
- B24B7/16—Single-purpose machines or devices for grinding end-faces, e.g. of gauges, rollers, nuts, piston rings
- B24B7/17—Single-purpose machines or devices for grinding end-faces, e.g. of gauges, rollers, nuts, piston rings for simultaneously grinding opposite and parallel end faces, e.g. double disc grinders
-
- 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
- H01L21/304—Mechanical treatment, e.g. grinding, polishing, cutting
-
- 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
Definitions
- the present invention relates to a carrier manufacturing method for a double-side polishing apparatus and a wafer double-side polishing method.
- a carrier for the double-side polishing apparatus having the same number of holding holes as the number of wafers is installed on the surface plate.
- the wafer is held by the holding holes of the carrier, the wafer is sandwiched from both surfaces by the polishing cloth provided on the upper and lower surface plates, and polishing is performed while supplying the polishing agent to the polishing surface.
- the carrier for the double-side polishing apparatus is formed to be thinner than the wafer, and is made of a metal such as stainless steel or titanium, or a hard resin such as glass epoxy.
- the metal carrier has an insert made of resin inside the wafer holding hole in order to prevent the inner peripheral portion of the wafer holding hole from coming into contact with the outer peripheral portion of the wafer and causing damage.
- This insert material is formed by fitting or injection molding.
- the insert material subjected to lapping and polishing is fitted to the carrier base material and bonded and applied while applying a load perpendicular to the insert material.
- a technique for performing drying is mentioned.
- the inner peripheral portion of the insert material is in contact with the outer peripheral portion of the wafer, it is important in making the edge shape of the wafer. Since this insert material is desired to be equivalent to the height of the carrier base material, it is necessary to process the part that protrudes after inserting a thicker insert by carrier rising polishing.
- this insert material is desired to be equal to the height of the carrier base material is that the retainer effect acting on the edge portion of the wafer differs depending on the height of the insert material.
- the retainer effect has an effect of preventing the edge portion of the wafer from drastically sagging. Therefore, the shape of the sag or sag at the edge portion depends on the height of the insert material and the thickness of the wafer.
- the flatness of the edge portion of the wafer after double-side polishing is uneven on the front and back surfaces.
- the thickness variation of an insert material and a carrier base material is mentioned.
- the insert resin is preliminarily polished to a uniform thickness and then fitted into a carrier.
- the insert material when the insert material is fitted into the carrier base material, it is difficult to fit it symmetrically on the front surface and the back surface, and the insert material is fixed in a state shifted from the front side or the back side. The difference in level difference between the material and the insert material will occur.
- the present invention has been made in view of the above-described problems, and provides a carrier manufacturing method for a double-side polishing apparatus and a double-side polishing method for a wafer that can improve the flatness of an edge portion of a wafer after double-side polishing.
- the purpose is to provide.
- a carrier base material used in a double-side polishing apparatus having an upper surface plate and a lower surface plate to which a polishing cloth is attached and having a holding hole for holding a wafer is formed.
- a manufacturing method of a carrier for a double-side polishing apparatus, which is disposed along an inner periphery of the holding hole and has an insert material formed with an inner peripheral portion in contact with the outer peripheral portion of the wafer The carrier base material, a preparation step for preparing the insert material thicker than the carrier base material, and the insert material so that the insert material protrudes from both the front side and the back side of the carrier base material.
- the step of fitting into the holding hole, the surface side protrusion amount of the insert material protruding from the front surface side of the carrier base material, and the back surface side protrusion amount of the insert material protruding from the back surface side of the carrier base material are measured.
- Manufacturing a carrier for a double-side polishing apparatus comprising: a rising polishing step for rising polishing the carrier at the set rotation speeds of the upper surface plate and the lower surface plate The law provides.
- the preparation step It is preferable to prepare the insert material that is 10 ⁇ m or more and 40 ⁇ m or less thicker than the thickness of the carrier base material.
- the relative rotational speed of the other is relative to the relative rotational speed of one of the carriers. It is preferable to set the rotation speeds of the upper surface plate and the lower surface plate so as to be 1.5 times or more.
- the difference in the amount of protrusion can be made sufficiently small, and the number of rotations can be set so that the carrier rising polishing is performed more efficiently.
- the rotational speeds of the upper surface plate and the lower surface plate are set so that the relative rotational speeds of the upper surface plate and the lower surface plate with respect to the carrier when rising and polishing the carrier are 0 rpm or more and 30 rpm or less, respectively. It is preferable to set.
- an alkaline aqueous solution in which an abrasive having an average abrasive grain size of 60 nm or more is diluted 2 to 5 times with a solvent.
- the measurement step is performed again after the rising polishing step, and the setting step, the standing step are performed until the difference between the front side protrusion amount and the rear side protrusion amount measured in the measurement step is 5 ⁇ m or less. It is preferable to repeat the upper polishing step and the measurement step.
- a method for polishing a wafer on both sides The carrier manufactured by the carrier manufacturing method for the double-side polishing apparatus of the present invention described above is disposed between the upper surface plate and the lower surface plate to which the polishing cloth is attached, and the holding hole formed in the carrier Provided is a double-side polishing method for a wafer, wherein the wafer is held and double-side polished.
- the difference between the protrusion amount on the front surface side and the protrusion amount on the back surface side of the insert material from the carrier base material can be reduced.
- the symmetry of the insert material can be improved, whereby the flatness of the edge portion of the wafer after double-side polishing can be improved.
- the present invention is not limited to this.
- the insert material when the insert material is fitted into the carrier base material, the insert material is fixed in a state shifted to the front side (or back side), and the wafer is double-side polished using such a carrier. There is a problem that the flatness of the edge portion of the wafer after double-side polishing is deteriorated.
- the present inventors have intensively studied to solve such problems.
- the number of rotations of the upper and lower surface plates was set, and it was found that the carrier was ground and polished at the set number of rotations of the upper and lower surface plates.
- the difference between the protrusion amount on the front surface side and the protrusion amount on the back surface side of the insert material from the carrier base material can be reduced, the symmetry of the insert material on the front surface and the back surface of the carrier base material can be improved. This has led to the idea that the flatness of the edge portion of the wafer after double-side polishing can be improved. And the best form for implementing these was scrutinized and the present invention was completed.
- FIG. 2 shows an example of a carrier for a double-side polishing apparatus.
- the carrier 1 is arranged along the inner periphery of a carrier base material 3 in which a holding hole 2 for holding a wafer is formed, and the holding hole 2 of the carrier base material 3, and an inner peripheral portion in contact with the outer peripheral portion of the wafer is
- the formed insert material 4 is included.
- the chamfered portion of the wafer can be protected by the insert material 4.
- Such a carrier 1 is used, for example, when a wafer W is double-side polished in a 4-way double-side polishing apparatus 10 as shown in FIG.
- the double-side polishing apparatus 10 includes an upper surface plate 11 and a lower surface plate 12 that are provided opposite to each other in the vertical direction.
- a polishing cloth 13 is affixed to the upper and lower surface plates 11 and 12 respectively.
- a sun gear 14 is provided at the center between the upper surface plate 11 and the lower surface plate 12, and an internal gear 15 is provided at the periphery.
- the teeth of the sun gear 14 and the internal gear 15 are engaged with the outer peripheral teeth of the carrier 1, and the carrier 1 is rotated as the upper surface plate 11 and the lower surface plate 12 are rotated by a drive source (not shown). Revolving around the sun gear 14 while rotating. At this time, both surfaces of the wafer W held by the holding holes 2 of the carrier 1 are simultaneously polished by the upper and lower polishing cloths 13.
- the slurry 17 is supplied from the slurry supply device 16 to the polishing surface of the wafer W.
- a preparatory step for preparing a carrier base material 3 as shown in FIG. 2 and an insert material 4 thicker than the carrier base material 3 is performed (SP1 in FIG. 1).
- the holding hole 2 exemplifies one carrier base material 3, but of course it is not limited to this and may have a plurality of holding holes.
- an insert material 4 that is 10 ⁇ m or more and 40 ⁇ m or less thicker, more preferably 15 ⁇ m or more and 25 ⁇ m or less thicker than the thickness of the carrier base material 3.
- the insert material 4 is preferably prepared, for example, of a hard resin material.
- the carrier base material 3 is preferably made of a metal such as stainless steel or titanium, or is subjected to surface hardening treatment.
- the present invention is not particularly limited to these materials.
- the front-side protrusion amount and the back-side protrusion amount can be measured using, for example, a contact-type step measuring instrument.
- a setting step is performed for setting the rotational speeds of the upper surface plate 11 and the lower surface plate 12 when the carrier 1 is ground and polished so that the difference between the front surface side protrusion amount and the back surface side protrusion amount is small (FIG. 1). SP4).
- the relative rotational speed of the surface side surface plate with a large protrusion amount of the insert material 4 is increased, or the relative rotational speed of the surface side surface plate with a small protrusion amount of the insert material 4. It is possible to control the machining allowance of the insert material 4 on the front surface and the back surface.
- the relative rotational speed may be set with reference to the ratio of the front-side protrusion amount and the back-side protrusion amount. In this case, the absolute value of the ratio of the protrusion amount and the ratio of the rotational speed does not necessarily have to coincide. If the relationship between the polishing speed of the insert material and the platen rotation speed is obtained in advance, the relative rotation speed can be easily set.
- the relative rotational speed of the other is 1 relative to the relative rotational speed of the other. It is preferable to set the rotational speeds of the upper surface plate 11 and the lower surface plate 12 so as to be 5 times or more. In this way, the difference in the amount of protrusion can be sufficiently reduced, and the number of rotations can be set so that the rising polishing of the carrier 1 can be performed more efficiently. It should be noted that if the relative rotational speed of the other relative to the relative rotational speed of the other is set to 4 times, efficiency is sufficient.
- the upper surface plate 11 and the lower surface plate 12 are set so that the relative rotational speeds of the upper surface plate 11 and the lower surface plate 12 with respect to the carrier 1 when the carrier 1 is ground and polished are 0 rpm or more and 30 rpm or less, respectively. It is preferable to set the number of rotations. If it does in this way, the rotation speed which can perform the starting grinding
- the rising polishing step of rising and polishing the carrier 1 at the respective rotational speeds of the upper surface plate 11 and the lower surface plate 12 set in the above setting step is performed (SP5 in FIG. 1).
- an alkaline aqueous solution in which an abrasive having an average abrasive grain size of 60 nm or more is diluted 2 to 5 times with a solvent. In this way, the rising polishing can be performed efficiently. If the average abrasive grain size is 100 nm, efficiency is sufficient.
- urethane foam pad having a Shore A hardness of 85-95 for the polishing cloth 13.
- the measurement step (SP6) is performed again after the rising polishing step (SP5), and the difference between the front side protrusion amount and the rear side protrusion amount measured in this measurement step (SP6) is 5 ⁇ m or less. More preferably, the setting step (SP4), the rising polishing step (SP5), and the measurement step (SP6) are repeated until the thickness becomes 2 ⁇ m or less, more preferably 1 ⁇ m. In this way, the symmetry of the insert material 4 between the front surface and the back surface of the carrier base material 3 can be improved more reliably. The difference itself is preferably smaller. If necessary, the above process can be repeated until the difference disappears (the difference is 0 ⁇ m).
- the setting step (SP4) is performed again, and when the difference between the front surface side protrusion amount and the rear surface side protrusion amount is less than the desired value. Therefore, it can be determined that the vertical polishing is completed (SP8).
- the carrier for the double-side polishing apparatus of the present invention as described above is a manufacturing method, the difference between the protrusion amount on the front surface side and the protrusion amount on the back surface side of the insert material from the carrier base material can be reduced.
- the symmetry of the insert material on the front surface and the back surface of the base material can be improved, and thereby the flatness of the edge portion of the wafer after double-side polishing can be improved.
- a carrier manufactured by the above-described carrier manufacturing method for a double-side polishing apparatus of the present invention is disposed between an upper surface plate and a lower surface plate to which a polishing cloth is attached.
- the wafer is held in the holding holes formed in the carrier and polished on both sides. In this way, the flatness of the edge portion of the wafer after double-side polishing can be improved.
- the wafer W is held in the holding hole 2 of the carrier 1.
- the carrier 1 holding the wafer W is inserted between the upper and lower surface plates 11 and 12 of the double-side polishing apparatus 10.
- the carrier 1 is rotated and revolved while rotating the upper and lower surface plates 11 and 12 while supplying the slurry 17 to the polishing surface by the slurry supply device 16.
- both surfaces of the wafer W can be slidably brought into contact with the polishing pad 13, whereby the wafer W can be polished on both sides.
- the carrier is provided with only one holding hole as shown in FIG.
- the present invention is not limited to this, and the present invention can also be applied to a single carrier provided with a plurality of holding holes and an insert material corresponding thereto.
- Example 2 A carrier base material made of pure titanium, having a DLC coating treatment of about 2 ⁇ m on the surface and having a thickness after coating of about 776 ⁇ m was prepared. Further, as the insert material, a glass fiber reinforced epoxy resin (EG) having a thickness of 790 to 800 ⁇ m, which has been lapped and polished in advance, was prepared (preparation step).
- EG glass fiber reinforced epoxy resin
- the insert material was fitted into the holding hole so that the insert material protruded from both the front side and the back side of the carrier base material (fitting process).
- the front side protrusion amount of the insert material protruding from the front surface side of the carrier base material and the back surface side protrusion amount of the insert material protruding from the back surface side of the carrier base material were measured (measurement process).
- the front side protrusion amount and the back side protrusion amount were measured using Mitutoyo Surf Test SJ-400. The results at this time are shown in FIG. 5 and FIG. 6 together with the measurement results after rising polishing described later.
- the front-side protrusion amount before startup polishing was 14.22 ⁇ m
- the rear-side protrusion amount was 7.82 ⁇ m. That is, the difference between the front-side protrusion amount and the back-side protrusion amount before the rising polishing was 6.4 ⁇ m, and the ratio was 1.82.
- the measurement process is performed again after the start-up polishing process, and the setting process, the start-up polishing process, and the measurement process are repeated until the difference between the front-side protrusion amount and the back-side protrusion amount measured in this measurement step is 1 ⁇ m or less. It was.
- the relative rotational speed of the upper surface plate and the lower surface plate with respect to the carrier when the carrier is ground and polished the relative rotational speed of the upper surface plate is the lower surface plate.
- the number of revolutions was set so that it was doubled in the rising polishing (first time) and 1.5 times in the rising polishing (second time).
- the rising polishing time was 60 minutes for rising polishing (first time) and 120 minutes for rising polishing (second time).
- a double-side polishing machine in which SF5000 made by Fujibo Ehime, which is a foamed urethane pad with a Shore A hardness of 90, is used as a polishing cloth on the upper and lower surface plates of a double-side polishing machine DPS-20B made by Fujikoshi Kikai Kogyo. It was.
- a polishing agent of COMPOL80 manufactured by Fujimi Incorporated with an average abrasive particle size of 77 nm was diluted 3 times with a solvent to an abrasive concentration of 13.5 wt%, pH 10.5 A KOH-based aqueous alkaline solution was used.
- the amount of protrusion on the front surface side after the carrier rising polishing (first time) was 3.50 ⁇ m
- the amount of protrusion on the back surface side was 1.96 ⁇ m. That is, the difference between the protrusion amount on the front surface side and the protrusion amount on the rear surface side after the rising polishing (first time) of the carrier was 1.54 ⁇ m.
- the protrusion amount on the front surface side after the rising polishing of the carrier (second time) was 1.48 ⁇ m
- the protrusion amount on the back surface side was 0.78 ⁇ m. That is, the difference between the protrusion amount on the front surface side and the protrusion amount on the back surface side after the rising polishing (second time) of the carrier was 0.7 ⁇ m.
- a carrier base material similar to that of the example and an insert material having a thickness of 780 to 790 ⁇ m which had been lapped and polished in advance were prepared (SP101 in FIG. 7), and normal fitting was performed (SP102). Thereafter, the displacement on the front side and the back side of the carrier base material was measured in the same manner as in the example (SP103 in FIG. 7). The results at this time are shown in FIG. 8 and FIG. 9 together with the measurement results after rising polishing described later.
- the insert material was greatly displaced to the surface side when the insert material was fitted.
- the amount of protrusion on the front surface side before startup polishing was 23.29 ⁇ m
- the amount of protrusion on the back surface side was ⁇ 13.45 ⁇ m.
- the relative rotational speed of the upper surface plate and the lower surface plate with respect to the carrier when the carrier is upwardly polished is determined in the same manner as in the normal double-side polishing of a wafer.
- the relative rotational speed of the board and the relative rotational speed of the lower surface plate were made equal.
- the rising polishing time was 60 minutes for rising polishing (first time) and 150 minutes for rising polishing (second time).
- the amount of protrusion on the surface side after the rising polishing of the carrier (first time) in the comparative example is 6.59 ⁇ m
- the amount of protrusion on the surface side after the rising polishing of the carrier (second time) is 4.95 ⁇ m. there were. Therefore, after the carrier rising polishing (second time), the protrusion amount on the surface side became 5 ⁇ m or less, and the carrier rising polishing was completed at this point.
- the insert material greatly deviates to the surface side when the insert material is fitted. The amount cannot be corrected, and the symmetry between the front surface and the back surface of the carrier base material is poor.
- the insert material is displaced and fixed to the surface when the insert material is fitted, but the insert material protrudes on both sides. From the measurement result of the level difference before the start polishing, the amount of protrusion on the surface side is larger, so the start polishing was performed with the relative speed of the upper surface plate and the carrier set larger than the relative speed of the lower surface plate. As a result, in the example, it was possible to manufacture a carrier in which the symmetry of the insert material on the front surface and the back surface of the carrier base material after the rising polishing was better than that in the comparative example.
- a plurality of carriers were manufactured. Then, using these manufactured carriers, double-side polishing of a silicon wafer having a diameter of 300 mm was performed in a total of 5 batches.
- SF5000 manufactured by Fujibo Ehime which is a foamed urethane pad with a Shore A hardness of 90 as the polishing cloth, is placed on the upper and lower surface plates of a double-side polishing machine DPS-20B manufactured by Fujikoshi Kikai Kogyo. Was used.
- silica-based abrasives RDS-H11201 and RDS-H11202 (average particle diameters 74 nm and 89 nm) manufactured by Fujimi Incorporated have a mixing ratio of 1: 1 and an abrasive concentration of 2.4 wt%.
- a pH 10.5 KOH-based alkaline aqueous solution was used.
- FIG. 10 shows the flatness measurement result (ESFQR max ) on the front surface side of the wafer after double-side polishing
- FIG. 11 shows the flatness measurement result (Back-ZDD) on the back surface side of the wafer after double-side polishing. .
- the average value of ESFQR max was 17.1 nm in the comparative example.
- the average value of ESFQR max was improved to 13.5 nm.
- the average value of Back-ZDD was 8.6 nm / mm 2 in the comparative example.
- the average value of Back-ZDD was improved to 4.2 nm / mm 2 .
- the carrier manufacturing method of the present invention can improve the symmetry of the insert material on the front surface and the back surface of the carrier base material, thereby improving the flatness of the edge portion of the wafer after double-side polishing. I was able to.
- the present invention is not limited to the above embodiment.
- the above-described embodiment is an exemplification, and the present invention has any configuration that has substantially the same configuration as the technical idea described in the claims of the present invention and that exhibits the same effects. Are included in the technical scope.
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Abstract
Description
前記キャリア母材と、該キャリア母材よりも厚い前記インサート材を準備する準備工程と、前記インサート材が前記キャリア母材の表面側及び裏面側の両面から突出するように、前記インサート材を前記保持孔に嵌め込む工程と、前記キャリア母材の表面側から突出した前記インサート材の表面側突出量及び、前記キャリア母材の裏面側から突出した前記インサート材の裏面側突出量をそれぞれ測定する測定工程と、前記表面側突出量と前記裏面側突出量の差が小さくなるように、前記キャリアを立上研磨する際の前記上定盤及び前記下定盤の回転数を設定する設定工程と、該設定された前記上定盤及び前記下定盤のそれぞれの回転数で前記キャリアを立上研磨する立上研磨工程とを有することを特徴とする両面研磨装置用のキャリアの製造方法を提供する。
前記キャリア母材の厚さよりも、10μm以上40μm以下厚い前記インサート材を準備することが好ましい。
前記キャリアを立上研磨する際の前記キャリアに対する前記上定盤及び前記下定盤の相対的な回転数について、一方の前記相対的な回転数に対して、もう一方の前記相対的な回転数が1.5倍以上となるように、前記上定盤及び前記下定盤の回転数を設定することが好ましい。
前記キャリアを立上研磨する際の前記キャリアに対する前記上定盤及び前記下定盤の相対的な回転数が、それぞれ0rpm以上30rpm以下となるように、前記上定盤及び前記下定盤の回転数を設定することが好ましい。
平均砥粒径60nm以上の研磨剤を溶媒により2~5倍で希釈したアルカリ性水溶液を使用することが好ましい。
研磨布が貼付された上定盤と下定盤との間に、上記した本発明の両面研磨装置用のキャリアの製造方法により製造した前記キャリアを配置し、該キャリアに形成された前記保持孔に前記ウェーハを保持して両面研磨することを特徴とするウェーハの両面研磨方法を提供する。
上述したように、インサート材をキャリア母材に嵌め込む際に、インサート材が表側(又は裏側)にずれた状態で固定されてしまい、このようなキャリアを用いてウェーハの両面研磨を行った場合、両面研磨後のウェーハのエッジ部のフラットネスが悪化してしまうという問題があった。
なお、上記の、一方の相対的な回転数に対する、もう一方の相対的な回転数の設定は、4倍もあれば効率面で十分である。
なお、上記平均砥粒径は100nmもあれば効率面で十分である。
なお、上記の差自体はより小さい方が好ましく、必要であれば、差がなくなる(差が0μm)まで上記工程を繰り返し行うことも可能である。
キャリア母材として、純チタンから成り、表面に約2μmのDLCコーティング処理を施して、コーティング後の厚みが約776μmのものを準備した。また、インサート材として、事前にラップ及び研磨加工を施した厚みが790~800μmのガラス繊維強化エポキシ樹脂(EG)のものを準備した(準備工程)。
実施例と同様の両面研磨装置を用いて、図7に示す工程図に従って、両面研磨装置用のキャリアの製造を行った。
Claims (7)
- 研磨布が貼付された上定盤及び下定盤を有する両面研磨装置で用いられ、ウェーハを保持するための保持孔が形成されたキャリア母材と、前記保持孔の内周に沿って配置され、前記ウェーハの外周部と接する内周部が形成されたインサート材とを有する両面研磨装置用のキャリアの製造方法であって、
前記キャリア母材と、該キャリア母材よりも厚い前記インサート材を準備する準備工程と、前記インサート材が前記キャリア母材の表面側及び裏面側の両面から突出するように、前記インサート材を前記保持孔に嵌め込む工程と、前記キャリア母材の表面側から突出した前記インサート材の表面側突出量及び、前記キャリア母材の裏面側から突出した前記インサート材の裏面側突出量をそれぞれ測定する測定工程と、前記表面側突出量と前記裏面側突出量の差が小さくなるように、前記キャリアを立上研磨する際の前記上定盤及び前記下定盤の回転数を設定する設定工程と、該設定された前記上定盤及び前記下定盤のそれぞれの回転数で前記キャリアを立上研磨する立上研磨工程とを有することを特徴とする両面研磨装置用のキャリアの製造方法。 - 前記準備工程において、
前記キャリア母材の厚さよりも、10μm以上40μm以下厚い前記インサート材を準備することを特徴とする請求項1に記載の両面研磨装置用のキャリアの製造方法。 - 前記設定工程において、
前記キャリアを立上研磨する際の前記キャリアに対する前記上定盤及び前記下定盤の相対的な回転数について、一方の前記相対的な回転数に対して、もう一方の前記相対的な回転数が1.5倍以上となるように、前記上定盤及び前記下定盤の回転数を設定することを特徴とする請求項1又は請求項2に記載の両面研磨装置用のキャリアの製造方法。 - 前記設定工程において、
前記キャリアを立上研磨する際の前記キャリアに対する前記上定盤及び前記下定盤の相対的な回転数が、それぞれ0rpm以上30rpm以下となるように、前記上定盤及び前記下定盤の回転数を設定することを特徴とする請求項1から請求項3のいずれか一項に記載の両面研磨装置用のキャリアの製造方法。 - 前記立上研磨工程において、
平均砥粒径60nm以上の研磨剤を溶媒により2~5倍で希釈したアルカリ性水溶液を使用することを特徴とする請求項1から請求項4のいずれか一項に記載の両面研磨装置用のキャリアの製造方法。 - 前記立上研磨工程後に再び前記測定工程を行い、該測定工程において測定される前記表面側突出量と前記裏面側突出量の差が5μm以下となるまで、前記設定工程、前記立上研磨工程及び前記測定工程を繰り返し行うことを特徴とする請求項1から請求項5のいずれか一項に記載の両面研磨装置用のキャリアの製造方法。
- ウェーハを両面研磨する方法であって、
研磨布が貼付された上定盤と下定盤との間に、請求項1から請求項6のいずれか一項に記載の製造方法により製造した前記キャリアを配置し、該キャリアに形成された前記保持孔に前記ウェーハを保持して両面研磨することを特徴とするウェーハの両面研磨方法。
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