US20010053665A1 - Polishing head of a chemical and mechanical polishing apparatus - Google Patents
Polishing head of a chemical and mechanical polishing apparatus Download PDFInfo
- Publication number
- US20010053665A1 US20010053665A1 US09/847,292 US84729201A US2001053665A1 US 20010053665 A1 US20010053665 A1 US 20010053665A1 US 84729201 A US84729201 A US 84729201A US 2001053665 A1 US2001053665 A1 US 2001053665A1
- Authority
- US
- United States
- Prior art keywords
- retainer ring
- carrier
- wafer
- polishing head
- air
- 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
Links
Images
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
- H01L21/04—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
-
- 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
- B24B37/30—Work carriers for single side lapping of plane surfaces
- B24B37/32—Retaining rings
Definitions
- the present invention relates to a chemical and mechanical polishing apparatus. More particularly, the present invention relates to the polishing head of a chemical and mechanical polishing apparatus.
- FIG. 4 is a cross-sectional view of the retainer ring.
- a polishing head of a chemical and mechanical polishing apparatus according to the present invention will be described in detail hereinafter with reference to the FIGS. 2 - 4 .
- the housing 110 has a body portion 110 a for guiding the carrier 120 so that the carrier 120 can move upwardly and downwardly, and a flange portion 110 b that extends radially from the lower end of the body portion 110 a .
- the carrier 120 is connected to the housing 110 at the flange portion 110 b.
- the resilient plate 132 comprises a disc of rubber or a synthetic resin.
- the resilient plate also has a plurality of through-holes disposed radially outwardly of the center of the resilient plate 132 at the outer peripheral portion of the resilient plate 132 .
- the resilient plate 132 is fixed to the chucking plate 134 by the first connecting ring 136 b .
- the resilient plate 132 is disposed over the lower surface of the chucking plate 134 .
- the outer peripheral portion of the chucking plate 132 is bent upwardly along the outer peripheral edge of the chucking plate 134 and then is bent again into contact with the upper surface of the chucking plate 134 .
- the first connecting ring 136 b is disposed on the outer peripheral portion of the resilient plate 132 such that the though-holes formed in the first connecting ring 136 b are aligned with the through-holes formed in the outer peripheral portion of the resilient plate 132 .
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (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)
- Finish Polishing, Edge Sharpening, And Grinding By Specific Grinding Devices (AREA)
- Mechanical Treatment Of Semiconductor (AREA)
Abstract
A polishing head of a chemical and mechanical polishing apparatus includes a retainer ring which adheres more uniformly to a polishing pad. The retainer ring surrounds and protects a wafer chucked to the polishing head. The bottom surface of the retainer ring is inclined by a predetermined angle from the outer periphery thereof towards the inner periphery thereof. A resilient fixing plate disposed against the upper surface of the inner peripheral portion of the retainer ring provides a seal between the retainer ring and the carrier. Therefore, when the retainer ring is pressed against a polishing pad and the inner peripheral portion of the retainer ring is pushed downwardly due to the resiliency of the fixing plate, the retainer ring flexes such that uniform pressure is produced between the bottom surface of the retainer ring and the polishing pad. Hence, the wafer will be polished uniformly.
Description
- 1. Field of the Invention
- The present invention relates to a chemical and mechanical polishing apparatus. More particularly, the present invention relates to the polishing head of a chemical and mechanical polishing apparatus.
- 2. Description of the Related Art
- A chemical and mechanical polishing process is used to planarize the front surface or the rear surface of a semiconductor wafer in the manufacturing of an integrated circuit on the wafer. The planarizing technology associated with the chemical and mechanical polishing process is becoming more important as the degree to which semiconductor integrated circuits are integrated becomes higher and the diameters of the semiconductor wafers become larger.
- The chemical and mechanical polishing (CMP) apparatus used to planarize surfaces of a wafer comprises a device for mounting and detaching a wafer cassette, a wafer moving device, a polishing device, a wafer cleaning device, and a controlling device. The polishing device, in turn, comprises a polishing head for supporting and pressing a wafer, a polishing plate to which a polishing pad is attached, a driving mechanism, a device for dressing the polishing pad, a device for cleaning a wafer chuck, and a slurry supplying device.
- In the mechanical aspect of the polishing process, material is removed at the surface of the wafer at a rate that is proportional to the polishing pressure and the polishing speed. In the chemical aspect of the polishing process, material is removed by a chemical reaction between the wafer surface and the slurry. As long as the polishing load, the polishing speed, the amount of slurry supplied, the friction between the wafer surface and the polishing pad, and the polishing temperature are uniform across the wafer surface, the planarizing is carried out over a wide area on the wafer and the residual layer will exhibit a uniform thickness. However, in practice, the above-mentioned parameters and the surface state of the polishing pad vary over time. Thus, the residual layer often exhibits an irregular thickness. Furthermore, the planarizing process can produce dishing and tinning phenomena, which lower the yield of the semiconductor device manufacturing process. Therefore, the above-mentioned parameters need to be controlled precisely through experimentation and the scientific process.
- In addition, under 1 μm of material is polished away in the chemical and mechanical polishing process, and 0.01 μm of surface planarizing degree is needed. Therefore, the way in which the wafer is supported is very important.
- One of the problems of the conventional chemical and mechanical polishing technology is that it can produce defects which reduce the die yield and product reliability. For example, if the pressure needed polishing a particular wafer is too high, the wafer carrier ring of the CMP apparatus will become considerably bent. Accordingly, the portion of the wafer carrier ring overlying the wafer will not be flat with respect to the wafer. Consequently, the flow of slurry flow becomes so bad that the wafer is polished irregularly.
- In addition, a rubber bladder of the conventional CMP apparatus can leak. Therefore, preventative maintenance must be carried out to check for such potential leakage. This maintenance requires the apparatus to be down for some period of time.
- Therefore, measures have been taken to reduce the bending of the retainer ring and the leakage of the bladder of a chemical and mechanical polishing head. For instance, U.S. Pat. No. 5,944,590 discloses a polishing device which includes a retainer ring rounded along the lower outer peripheral surface thereof. The difference between the lower surface of the retainer ring and the lower surface of the semiconductor wafer is 50 μm or less. U.S. Pat. No. 5,948,204 discloses a ring assembly which is attached to a rubber bladder. The ring assembly includes a plurality of rings. The first ring is made of a soft material, and supports a backing plate attached to the wafer while the wafer is being polished. The second ring is made of a hard material, and reduces the bending of the first ring while the wafer is being polished. The second ring is attached to a wafer carrier plate for preventing the rubber bladder from leaking.
- U.S. Pat. No. 5,664,988 also discloses an apparatus for polishing a semiconductor wafer, the apparatus including a wafer carrier ring and a support ring. Japanese Patent Laid-Open Publication No. Hei 8-339979 discloses a method for polishing a polished substrate retaining device and a substrate. A guide member of the polished substrate retaining device is annular, and includes a passage which extends radially therethrough.
- FIG. 1 is a cross-sectional view of a
conventional polishing head 10. As shown in FIG. 1, thepolishing head 10 includes ahousing 12, awafer carrier 14 that is mounted to thehousing 12 and includes awafer chucking plate 13, and awafer retainer ring 16 that is mounted to thecarrier 14 and maintains the wafer W in proper position on the wafer chucking plate. - The
wafer carrier 14 and theretainer ring 16 are mounted to thehousing 12 so as to be movable vertically relative to thehousing 12. A sealingring 15 made of a synthetic resilient material is disposed between thewafer carrier 14 and theretainer ring 16 to establish a seal therebetween. - In the
conventional polishing head 10, the wafer W is pressed against a polishing pad P by a biasing force applied to thewafer carrier 14, and the wafer W is polished while theretainer ring 16 is biased against the polishing pad P by thewafer carrier 14. Therefore, the wafer W is pressed uniformly against the polishing pad P so that the entire surface of the wafer W can be uniformly polished. - However, in the
polishing head 10, the outer edge of the lower surface of theretainer ring 16 is separated from the polishing pad P by the resilient force of theseal ring 15 that is exerted on the inner peripheral portion of theretainer ring 16. As a result, the pressure at which the wafer W supported by thechucking plate 13 and theretainer ring 16 are adhered to the polishing pad P becomes irregular during rotation of thepolishing head 10. Accordingly, the inner peripheral portion of theretainer ring 16 is polished by the polishing pad P to form particles, and scratches are formed on the polished surface of the wafer by these particles of theretainer ring 16. The scratches constitute damage to the polished surface of the wafer W. - Furthermore, the slurry supplied between the wafer W and the polishing pad P is not uniformly distributed over the polishing pad P because the
retainer ring 16 and the wafer are pressed non-uniformly against the polishing pad P. As a result, the surface of the wafer W is not polished flat. - An object of the present invention is to solve the above-described problem of the prior art. Accordingly, it is an object of the present invention to provide a polishing head of a chemical and mechanical polishing apparatus, which includes a retainer ring that will adhere uniformly to a polishing pad even when it is deflected by the resilient force of a sealing ring during the course of polishing a wafer.
- In order to achieve the above-mentioned object of the present invention, the bottom surface of the retainer ring is inclined upwardly by a predetermined angle as taken in the direction extending radially from the outer periphery of the ring towards the inner periphery thereof. The retainer ring is mounted to a carrier. The carrier is in turn connected to a housing defining air passages for guiding air into and out of the polishing head. A wafer chuck is also mounted to the carrier for chucking a wafer using suction. The retainer ring extends along the outer peripheral portion of the carrier, guides the wafer chuck as it is moved towards a polishing pad, and protects the wafer chucked by the wafer chuck.
- The bottom surface of the retainer ring is inclined so that when the inner peripheral portion is pushed downwardly by a sealing ring or the like, the bottom surface will be pressed uniformly against the polishing pad.
- Hence, the wafer will be polished uniformly. Moreover, the bottom surface of the retainer ring will not require polishing, thereby saving time and labor.
- The above and other objects, features and advantages of the present invention will become more apparent by referring to the following detailed description thereof made with reference to the accompanying drawings, of which:
- FIG. 1 is a cross-sectional view is a conventional polishing head of a chemical and mechanical polishing apparatus;
- FIG. 2 is a cross-sectional view of an embodiment of a polishing head of a chemical and mechanical polishing apparatus according to the present invention;
- FIG. 3 is a perspective view of a retainer ring of the polishing head according to the present invention; and
- FIG. 4 is a cross-sectional view of the retainer ring.
- A polishing head of a chemical and mechanical polishing apparatus according to the present invention will be described in detail hereinafter with reference to the FIGS.2-4.
- Referring first to FIG. 2, the polishing
head 100 of a chemical and mechanical polishing apparatus according to the present invention includes ahousing 110, acarrier 120 connected to thehousing 110 for supporting a wafer W that is to be polished by a polishing pad P, awafer chuck 130 that is mounted to thecarrier 120 and chucks the wafer W using suction, and aretainer ring 140 that is mounted to thecarrier 120. Theretainer ring 140 extends along the outer periphery of thecarrier 120, contacts the polishing pad P, guides thewafer chuck 130, and protects the wafer W chucked by thewafer chuck 130. - The
housing 110 has abody portion 110 a for guiding thecarrier 120 so that thecarrier 120 can move upwardly and downwardly, and aflange portion 110 b that extends radially from the lower end of thebody portion 110 a. Thecarrier 120 is connected to thehousing 110 at theflange portion 110 b. - The
body portion 110 a of thehousing 110 has a circular cross section. Thehousing 110 also includes aguide projection 112 integral with thebody portion 110 a and extending downwardly from the central portion of the lower surface of thebody portion 110 a. Thebody portion 110 a also has a first through-hole 114 a extending longitudinally through the axial center thereof from the upper surface to the lower surface thereof, and second and third through-holes body portion 110 a to the lower surface thereof at locations spaced radially outwardly of the first though-hole 114 a. The second and third through-holes hole 114 a. The first, second, and third through-holes head 100. - The
guide projection 112 has a through-hole 112 a. The through-hole 112 a is contiguous with the first through-hole 114 a extending through the center of thebody portion 110 a. The through-hole 112 a of theprojection 112 has a diameter that is larger than that of the first through-hole 114 a of thebody portion 110 a. - The
flange portion 110 b of thehousing 110 has a plurality of through-holes spaced from one another along the outer periphery of theflange portion 110 b. Thehousing 110 is connected to thecarrier 120 by screws inserted into these through-holes. - The
carrier 120 has abody portion 122 and aconnector 124 for connecting thebody portion 122 to thehousing 110 so that thebody portion 122 can be moved upwardly and downwardly by compressed air that is introduced and discharged through the second through-hole 114 b of thehousing 110. Thebody portion 122 of thecarrier 120 defines a first axial through-hole 122 a, a second axial through-hole 122 b, a firstannular recess 126 a in the upper surface of thebody portion 122 thereof, and a secondannular recess 126 b in the lower surface of thebody portion 122. - The first through-
hole 122 a has the same diameter as that of the through-hole 112 a formed in theprojection 112 of thehousing 110. The second through-hole 122 b spaced radially from the first through-hole 122 a and is open to the lower surface of thebody portion 122 within the secondannular recess 126 b - The first
annular recess 126 a is concentric with respect to the center of thebody portion 122 and is spaced radially inwardly from the outer periphery of the upper surface of thebody portion 122. A plurality of through-holes extend through the outer peripheral portion of thebody portion 122. Screws extend through these through-holes, respectively, and into tapped holes formed in theretainer ring 140 to fix theretainer ring 140 to thecarrier 120. - The second
annular recess 126 b is concentric with respect to the center of thebody portion 122 and is located mid-way between the center of thebody portion 122 and the outer periphery of the lower surface of thebody portion 122. The outer periphery of the lower surface of thebody portion 122 is stepped so as to define a first outer annular surface concentric with respect to the center of the lower surface of thebody portion 122, and a second annular surface extending radially inwardly from the first annular surface. the second annular surface is also concentric with respect to the center of the lower surface of thebody portion 122. Furthermore, the second annular surface is wider than the first outer annular surface. The outer periphery of the lower surface of thebody portion 122 also includes a third annular surface that extends at an inclination from the second annular surface to the secondannular recess 126 b. - The central portion of the
body portion 122 of thecarrier 120 is thinner than any other portion of thebody portion 122. Thebody portion 122 also has a plurality of tapped openings in the upper surface thereof between the central portion and the firstannular recess 126 a. The tapped openings are disposed radially about the central portion of thebody portion 122. Theconnector 124 of thecarrier 120 has anouter clamp 124 a that is fixed to the bottom surface of thehousing 110 by nuts and bolts, aninner clamp 124 b that is fixed to the upper surface of thecarrier 120 by screws extending into the tapped openings in the upper surface thereof, and an annularresilient sheet 124 c. The annularresilient sheet 124 c is made of rubber or a synthetic resin. The annularresilient sheet 124 c has a predetermined width, and the diameter of the annularresilient sheet 124 c is larger than that of theinner clamp 124 b, and is smaller than those of thecarrier 120 and theouter clamp 124 a. The outer circumferential portion of the annularresilient sheet 124 c is fixed to thehousing 110 by theouter clamp 124 a, whereas the inner circumferential portion of the annularresilient sheet 124 a is fixed to thecarrier 120 by theinner clamp 124 b. - More specifically, the
outer clamp 124 a of theconnector 124 comprises a body portion and a flange portion integral with the body portion. The inner diameter of theouter clamp 124 a is larger than the outer diameter of theinner clamp 124 b, and the outer diameter of theouter clamp 124 a is equal to the maximum diameter of thehousing 110. The flange portion of theouter clamp 124 a has a plurality of through-holes that correspond to the plurality of through-holes formed in theflange 110 b of thehousing 110. The outer circumferential portion of theresilient sheet 124 c is disposed between the bottom surface of thehousing 110 and theouter clamp 124 a. Theouter clamp 124 a is fixed to thehousing 110 by nuts and bolts inserted into the corresponding through-holes in the flange portion of theouter clamp 124 a and theflange 110 b of thehousing 110 so as to sandwich the outer circumferential portion of theresilient sheet 124 c therebetween. - The
inner clamp 124 b of theconnector 124 is disc-shaped. The radius of theinner clamp 124 b is equal to the distance from the center of thecarrier 120 to the firstannular recess 126 a. Theinner clamp 124 b has a central through-hole of a diameter that is equal to or greater than the outer diameter of theprojection 112, and a plurality of through-holes that correspond to the plurality of tapped holes in the upper surface of thebody portion 122 of thecarrier 120. Theinner clamp 124 b is fixed to thebody portion 122 by screws inserted into the corresponding through-holes in theinner clamp 124 b and the tapped holes in the upper surface of thebody portion 122 of thecarrier 120 so as to sandwich the inner circumferential portion of theresilient sheet 124 c therebetween. - The
inner clamp 124 b also has a through-hole, corresponding to the third through-hole 114 c of thehousing 110, and an elongate groove having a width that is equal to the diameter of the through-hole. The through-hole of theinner clamp 124 b is spaced radially outwardly of the center of theinner clamp 124 b, and the elongate groove extends radially in the lower surface of theinner clamp 124 b from the through-hole to a position corresponding to the second through-hole 122 b of thecarrier 120. Anair conduit 129 is disposed in the elongate groove. Theair conduit 129 has a first end connected to the third through-hole 114 c of thehousing 110 and a second end connected to anannular air cushion 128 to supply and discharge air to and from theair cushion 128. - The
annular air cushion 128 is disposed in the annular recess 126 defined at the lower surface of thecarrier 120. Theair cushion 128 is made of a flexible synthetic resin or rubber, and has an opening therein that allows air to be introduced therein or discharged therefrom. Theair cushion 128 is inflated by the pressure of compressed air that is supplied through theair conduit 129 to move thewafer chuck 130 downwardly. On the other hand, theair conduit 129 is deflated when the compressed air is discharged through theair conduit 129 to allow thewafer chuck 130 to move upwardly. - The
housing 110 is connected to thecarrier 120 so as to define anair chamber 120 a therebetween. Compressed air introduced through the second through-hole 114 b of thehousing 110 flows into theair chamber 120 a and forces thecarrier 120 downwardly relative tot he housing 100. When the compressed air is discharged through the second through-hole 114 b, a vacuum is created in theair chamber 120 a. As the result, thecarrier 120 is moved upwardly towards thehousing 110. - The
wafer chuck 130 comprises aresilient plate 132 that can be extended and retracted by air pressure, achucking plate 134 for supporting and chucking the wafer W, aconnector 136 for fixing theresilient plate 132 to thechucking plate 134 and connecting thechucking plate 134 to thecarrier 120, and aguide member 138 for guiding the connectingmember 136 as the chuckingplate 134 moves upwardly or downwardly. - The
resilient plate 132 comprises a disc of rubber or a synthetic resin. The resilient plate also has a plurality of through-holes disposed radially outwardly of the center of theresilient plate 132 at the outer peripheral portion of theresilient plate 132. - The
chucking plate 134 is also disc-shaped. A plurality of through-holes extend therethrough at locations spaced radially outwardly of the center of thechucking plate 134. Air is sucked through the through-holes to chuck the wafer W to thechucking plate 134. The chuckingplate 134 also has an annular recess in the upper surface thereof. The annular recess is concentric with respect to the center of theplate 134 and is located at the outer periphery of thechucking plate 134. A plurality of screw holes are disposed in the recess. - The
connector 136 comprises an annularresilient sheet 136 a (of rubber or a synthetic resin) that connects the chuckingplate 134 to thecarrier 120 such that anair chamber 130 a is defined between thecarrier 120 and thewafer chuck 130, a first connectingring 136 b fixing theresilient plate 132 to thechucking plate 134, a second connectingring 136 c fixing the inner peripheral portion of theresilient sheet 136 a to thechucking plate 134, and aresilient fixing ring 136 d fixing the outer peripheral portion of theresilient sheet 136 a to thecarrier 120. - The outer diameter of the first connecting
ring 136 b is significantly smaller than the outer diameter of thechucking plate 134. The first connectingring 136 b also has a plurality of through-holes that correspond to the screw holes formed in thechucking plate 134. A plurality of screw holes can be formed in the upper surface of theannular sheet 136 a in alignment with the through-holes of the first connectingring 136 b. - The
resilient plate 132 is fixed to thechucking plate 134 by the first connectingring 136 b. First, theresilient plate 132 is disposed over the lower surface of thechucking plate 134. Subsequently, the outer peripheral portion of thechucking plate 132 is bent upwardly along the outer peripheral edge of thechucking plate 134 and then is bent again into contact with the upper surface of thechucking plate 134. Next, the first connectingring 136 b is disposed on the outer peripheral portion of theresilient plate 132 such that the though-holes formed in the first connectingring 136 b are aligned with the through-holes formed in the outer peripheral portion of theresilient plate 132. Finally, screws are passed through the through-holes formed in the outer peripheral portions of the first connectingring 136 b and theresilient plate 132, and into engagement with the threads of the screw holes formed in the upper surface of thechucking plate 134 to fix theresilient plate 132 to thechucking plate 134. - The
second ring 136 c of theconnector 136 has an outer diameter that is smaller than the outer diameter of the first connectingring 136 b, and an inner diameter that is smaller than the inner diameter of the first connectingring 136 b. The inner peripheral surface of the second connectingring 136 c is machined so that it is inclined at a predetermined angle from the upper end thereof towards the lower end thereof. The diameter of the lower end of the inner peripheral surface of the second connectingring 136 c is larger than the diameter of the upper end of the inner peripheral surface. The second connectingring 136 c may also have a plurality of through-holes that correspond to the screw holes formed in the upper surface of the first connectingring 136 b. - The fixing
ring 136 d of theconnector 136 is made of a resilient synthetic resin or rubber. The fixingring 136 d has a thickness of about 1 mm. The maximum diameter of the fixingring 136 d is significantly smaller than the diameter of thecarrier 120. The fixingring 136 d fixes theresilient sheet 136 a to thecarrier 120, and seals the space between thecarrier 120 and theretainer ring 140. - The
resilient sheet 136 a has the same outer diameter as theresilient fixing ring 136 d. Theresilient sheet 136 a may have a plurality of through-holes in the inner peripheral portion thereof that is interposed between the first connectingring 136 b and the second connectingring 136 c. ln this case, theresilient sheet 136 a is disposed between the first connectingring 136 b and the second connectingring 136 c such that the through-holes formed in the inner peripheral portion of theresilient sheet 136 a are aligned with the screw holes formed in the first connectingring 136 b and the second connectingring 136 c. Screws are passed through the screw holes formed in the first connectingring 136 b and the through-holes formed in the inner peripheral portion of theresilient sheet 136 a and into engagement with the threads of the screw holes formed in the second connectingring 136 c. Accordingly, theresilient sheet 136 a is connected to the first and second connectingrings - Alternatively, both surfaces of the inner peripheral portion of the
resilient sheet 136 a may be coated with a binder, whereby the inner peripheral portion is bonded to the first connectingring 136 b and the second connectingring 136 c. - The outer peripheral portion of the
resilient sheet 136 a may also be coated with the binder, whereby the outer peripheral portion is bonded to the lower surface of thecarrier 120 and the fixingring 136 d. - The
guide member 138 comprises a disc-shaped member having a stepped portion at the outer periphery thereof, and an extending portion that extends upwardly from the center of theguide member 138. Theguide member 138 has a through-hole that extends from the upper end of the extending portion to the lower surface of theguide member 138. The outer diameter of the extending portion of theguide member 138 is equal to or smaller than the inner diameter of theprojection 112 of thehousing 110 and the through-hole formed at the center of thecarrier 120. - As shown in FIG. 2, the extending portion of the
guide member 138 extends through the through-hole formed at the central portion of thecarrier 120 and into the through-hole formed in theprojection 112 of thehousing 110. The inclined inner peripheral surface of the second connectingring 136 c of thewafer chuck 130 is seated against the stepped portion of theguide member 138 such that the second connectingring 136 c can slide along the stepped portion and move upwardly or downwardly according to the pressure inchamber 130 a. The upper surface of theguide member 138 is adhered to the lower surface of thecarrier 120. - The through-hole formed in the
guide member 138 communicates with the first through-hole 114 a formed in thehousing 110, and with theair chamber 130 b defined by theguide member 138, the chuckingplate 134, theconnector 136, and theresilient plate 132. Therefore, when air is discharged from theair chamber 130 b through the through-hole formed in theguide member 138 and the first through-hole 114 a formed in thehousing 110, a portion of theresilient plate 132 disposed on the lower surface of thechucking plate 134 is sucked into the through-holes formed in thechucking plate 134. Consequently, a vacuum is created between theresilient plate 132 and the wafer W, whereby the wafer W is adhered to theresilient plate 132. - On the other hand, the connecting
member 136 of thewafer chuck 130 defines theair chamber 130 a together with thecarrier 120 and theguide member 138. The pressure in theair chamber 130 a is raised when theair cushion 128 is inflated. As a result, the second connectingring 136 c of theconnector 136, the first connectingring 136 b, and thechucking plate 134 are moved downwardly. Conversely, if theair cushion 128 is contracted by discharging the air therefrom, the air pressure in theair chamber 130 a is decreased. As a result, the second connectingring 136 c, thefirst ring 136 b, and thechucking plate 134 are moved upwardly by a restoring force exerted by theresilient sheet 136 a of theconnector 136. - Referring now to FIGS. 3 and 4, the
retainer ring 140 of the polishinghead 100 is made of a resin such as a polyphenylene sulfide PPS (resin). However, theretainer ring 140 can be made of an acethal resin or a polyether sulfone (PES) resin. - In general, the
retainer ring 140 is made by cutting a section from a cylindrical body of PPS resin. Then, the section is shaped using a lathe. The inner diameter of theretainer ring 140 is about 200 mm, the outer diameter thereof is about 240 to 250 mm, and the width of the lower surface thereof is about 20 to 25 mm. - Furthermore, as shown in FIGS. 3 and 4, the retainer ring has a
first step 142 and asecond step 144 at the upper portion of the inner periphery thereof. The width and the height of thefirst step 142 are typically the same as the width and the thickness of the fixingring 136 d, respectively. However, the height of thefirst step 142 may be smaller than the thickness of the fixingring 136 d. Thesecond step 144 of theretainer ring 140 is engaged with a jaw portion of thecarrier 120. Therefore, the width and the height of the second step are the same as the width and the height of the jaw portion. - The
lowermost surface 146 of theretainer ring 140 is machined so that it is inclined with respect to a (horizontal) plane orthogonal to the longitudinal axis of the ring by about 0.8 to 0.9 degrees, in the absence of any forces exerted on the ring. Preferably, the angle of inclination is 0.85 degrees. The inclined surface of theretainer ring 140 extends upwardly from the outer periphery of theretainer ring 140 towards the inner periphery of theretainer ring 140, when viewed from the bottom of theretainer ring 140. Thelowermost surface 146 of the retainer ring thus subtends anangle 15 of about 89 degrees with respect to the vertical. The outer peripheral surface of theretainer ring 140 is 0.35 mm longer than the inner peripheral surface of theretainer ring 140. - A plurality of screw holes148, preferably twelve
screw holes 148, are formed in the outer peripheral portion of the upper surface of theretainer ring 140. Theretainer ring 140 is fixed to thecarrier 120 by screws extending through the through-holes of thecarrier 120 and into engagement with the threads of the screw holes 148 formed in theretainer ring 140. - On the other hand, twelve holes (not shown) are formed between the screw holes148 in the outer periphery of the
retainer ring 140. Three holes (not shown) are formed in the inner periphery of theretainer ring 140 between each adjacent pair of screw holes 148, so that a total of thirty-six holes are formed in the inner periphery of theretainer ring 148. Each hole in the outer periphery of theretainer ring 140 communicates with a respective set of three holes in the inner periphery of theretainer ring 140. Slurry is supplied by a slurry supplying device to the holes in the outer periphery of theretainer ring 140 so that the slurry flows to the inner periphery of theretainer ring 140 through the holes in the inner periphery of theretainer ring 140. The slurry is used to polish the wafer W. - Next, the operation of the polishing
head 100 according to the present invention will be described in detail. - Referring again to FIG. 2, air is discharged from the
air chamber 120 a through the second through-hole 114 b of thehousing 110 to vacuum theair chamber 120 a. Accordingly, a vacuum is created in theair chamber 120 a and as a result, thecarrier 120 is adhered to the lower surface of thehousing 110. - With the
carrier 120 adhered to the lower surface of thehousing 110, theretainer ring 140 and thewafer chuck 130 are disposed in an upper position. Then, air is supplied into theair cushion 128 through theair conduit 129 extending through theinner clamp 124 b and the third throughhole 114 c of thehousing 110. As theair cushion 128 is thus inflated, pressure is produced in theair chamber 130 a defined by thecarrier body 122 of thecarrier 120, theguide member 138 of thewafer chuck 130 and theconnector 136. Thewafer chuck 130 is moved downwardly by the air pressure produced theair chamber 130 a. More specifically, the inclined surface of the second connectingring 136 slides along the stepped portion of theguide member 138, and theresilient plate 132 is moved downwardly until the lower surface thereof becomes coplanar with thebottom surface 146 of theretainer ring 140. Thus, thewafer chuck 130 is pressed against a wafer W fed to a location below the polishinghead 100 by a wafer feeding device (not shown). - In the state in which the
wafer chuck 130 is adhered to the wafer, air is discharged from theair chamber 130 b defined by theguide member 138, the chuckingplate 134, and the connectingmember 136 through the air passage of the extending portion of theguide member 138 and the first through-hole 114 a formed in thehousing 110. Consequently, a vacuum is produced in theair chamber 130 b, and theresilient plate 132 is sucked into the through-holes formed in thechucking plate 134. Therefore, a vacuum is also produced between the chuckingplate 134 and the wafer W such that the wafer W is firmly adhered to thechucking plate 134. - Subsequently, the air is discharged from the
air cushion 128 to deflate theair cushion 128. Therefore, the pressure in theair chamber 130 a is lowered. Accordingly, the chuckingplate 134 is moved upwardly by theresilient sheet 136 a of theconnector 136. Thus, the wafer W adhered to thechucking plate 134 is positioned above thebottom surface 146 of theretainer ring 140. - Next, air is supplied into the
air chamber 120 a while a vacuum is maintained in theair chamber 130 b. As a result, thebody portion 122 of thecarrier 120 is moved downwardly by the pressure produced in theair chamber 120 a. Theretainer ring 140 and thewafer chuck 130 connected to thecarrier 120 are also moved downwardly together with thecarrier 120. As shown in FIG. 2, theretainer ring 140 makes contact with the upper surface of the polishing pad P. As this happens, the inner peripheral portion of theretainer ring 140 is moved downwardly by the resilient force of the fixingring 136 d such that theretainer ring 140 contacts the upper surface of the polishing pad P uniformly. In this state, the wafer W is spaced above the upper surface of the polishing pad P. - However, the air continues to be supplied into the
air chamber 120 a. Thus, theretainer ring 140 remains in contact with the upper surface of the polishing pad P. In addition, a vacuum is maintained in theair chamber 130 b. Then, air is supplied into theair cushion 128. As theair cushion 128 is thus inflated, the pressure in theair chamber 130 a is increased. As a result, thewafer chuck 130 is moved downwardly. Hence, the lower surface of the wafer W chucked by thewafer chuck 130 is brought into contact with the upper surface of the polishing pad P. The pressure in theair chamber 130 a is increased until the wafer W is adhered firmly to the polishing pad P. - In this state, the slurry is supplied between the wafer W and the polishing pad P and the polishing
head 100 are rotated in opposite directions. Accordingly, the lower surface of the wafer W is polished. - Because the bottom surface of the
retainer ring 140 is inclined as described above, the bottom surface of the retainer ring is pressed uniformly against the polishing pad even though the fixingring 136 d exerts a downward force on the inner peripheral portion of theretainer ring 140. - Therefore, the retainer ring does not have to be polished. In addition, the retainer ring and the wafer are pressed uniformly against the polishing pad, thereby ensuring that the lower surface of the wafer is polished uniformly.
- Finally, although the present invention has been shown and described with respect to the preferred embodiments thereof, various changes thereto and modifications thereof will become readily apparent to those of ordinary skill in the art. Accordingly, all such changes and modifications are sen to be within the true spirit and scope of the present invention as hereinafter claimed.
Claims (11)
1. A polishing head of a chemical and mechanical polishing apparatus comprising:
a housing defining at least one air passage therein and through which air is introduced into and discharged from the polishing head;
a carrier connected to said housing so as to be movable up and down relative to said housing;
a wafer chuck mounted to said carrier and communicating with a said air passage defined in the housing so that a wafer can be chucked thereto by a vacuum created when air is discharged through said air passage;
a flexible retainer ring mounted to said carrier, and extending along an outer peripheral portion of the carrier around said wafer chuck so as to guide the wafer chuck and protect a wafer chucked by the wafer chuck,
the retainer ring having a lowermost surface that extends upwardly at a predetermined inclination relative to the horizontal from the outer periphery thereof towards the inner periphery thereof, in the absence of forces exerted on the retainer ring; and
a resilient member disposed in the polishing head so as to exert a downward force that causes the inner peripheral portion of said retainer ring to be pushed downwardly when the retainer ring is pressed downwardly against a polishing pad, whereby the retainer ring will flex to allow the lowermost surface of the retainer ring to be pressed uniformly against the polishing pad.
2. A polishing head according to , wherein an air chamber is defined by and between said wafer chuck and said carrier, and said resilient member is a fixing ring interposed between an upper surface of the retainer ring, at the inner peripheral portion thereof, and a lower surface of the carrier so as to seal the air chamber defined between the wafer chuck and the carrier.
claim 1
3. A polishing head according to , wherein the lowermost surface of said retainer ring is inclined at an angle of 0.8 to 0.9 degrees relative to the horizontal.
claim 1
4. A polishing head according to , wherein said retainer ring is made of a material selected from the group consisting of acethal resin, a polyphenylene sulfide resin, and a polyether sulfone (PES) resin.
claim 1
5. A polishing head of a chemical and mechanical polishing apparatus comprising:
a housing defining a plurality of air passages therein and through which air is introduced into and discharged from the polishing head;
a carrier connected to said housing so as to be movable up and down relative to said housing;
a wafer chuck including a chucking plate, and a connector connecting the chucking plate to the carrier such that said chucking plate is movable upwardly and downwardly relative to said carrier;
a guide member disposed between said carrier and said chucking plate, said connector defining a first air chamber together with the carrier, the chucking plate, and the guide member, said guide member and said chucking plate defining a second chamber therebetween, said guide member being engaged with said wafer chuck so as to guide said wafer chuck during up and down movement of said chucking plate, and said guide member having a through-hole that places one of said air passages defined in the housing in communication with the air chamber defined between the guide member and the chucking plate;
an air cushion disposed on the lower surface of said carrier, exposed to said first air chamber and communicating with one of said air passages defined in the housing, said air cushion being inflatable and deflatable by air introduced into and discharged from the polishing head via said one of the air passages so as to change the pressure in said first air chamber and thereby selectively move said chucking plate upwardly and downwardly;
a flexible retainer ring mounted to said carrier, and extending along an outer peripheral portion of the carrier around said wafer chuck so as to guide the wafer chuck and protect a wafer chucked by the wafer chuck,
the retainer ring having a lowermost surface that is extends upwardly at a predetermined inclination relative to the horizontal from the outer periphery thereof towards the inner periphery thereof, in the absence of forces exerted on the retainer ring; and
a resilient member disposed in the polishing head so as to exert a downward force that causes the inner peripheral portion of said retainer ring to be pushed downwardly when the retainer ring is pressed downwardly against a polishing pad, whereby the retainer ring will flex to allow the lowermost surface of the retainer ring to be pressed uniformly against the polishing pad.
6. A polishing head according to , wherein said resilient member is a fixing ring interposed between the inner peripheral portion of the retainer ring and a lower surface of said carrier, and sealing said first air chamber defined by said chucking plate and said carrier.
claim 5
7. A polishing head according to , wherein the lowermost surface of said retainer ring is inclined at an angle of 0.8 to 0.9 degrees relative to the horizontal.
claim 5
8. A polishing head according to , wherein said retainer ring is made of a material selected from the group consisting of acethal resin, a polyphenylene sulfide resin, and a polyether sulfone (PES) resin.
claim 5
9. A retainer ring for use in protecting a wafer chucked by a wafer chuck of a polishing head of a chemical mechanical polishing apparatus, said retainer ring comprising a flexible annular body having an uppermost surface, a lowermost surface, an inner peripheral surface, and an outer peripheral surface, an upper end of said inner peripheral surface adjacent the uppermost surface being stepped, a plurality of screw holes for allowing the annular body to be fixed to a carrier extending into the annular body from said uppermost surface thereof at respective locations adjacent said outer peripheral surface, and said lowermost surface being inclined upwardly at a predetermined inclination towards the uppermost surface from the outer peripheral surface of the annular body towards the inner peripheral surface thereof.
10. A polishing head according to , wherein the lowermost surface of said retainer ring is inclined at an angle of 0.8 to 0.9 degrees relative to a plane that extends orthogonally to the longitudinal axis of the annular body.
claim 9
11. A polishing head according to , wherein said retainer ring is made of a material selected from the group consisting of acethal resin, a polyphenylene sulfide resin, and a polyether sulfone (PES) resin.
claim 9
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
KR1020000026646A KR100335569B1 (en) | 2000-05-18 | 2000-05-18 | Polishing head of chemical and mechanical apparatus for polishing wafer |
KR2000-26646 | 2000-05-18 |
Publications (1)
Publication Number | Publication Date |
---|---|
US20010053665A1 true US20010053665A1 (en) | 2001-12-20 |
Family
ID=19669053
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US09/847,292 Abandoned US20010053665A1 (en) | 2000-05-18 | 2001-05-03 | Polishing head of a chemical and mechanical polishing apparatus |
Country Status (3)
Country | Link |
---|---|
US (1) | US20010053665A1 (en) |
JP (1) | JP2001358098A (en) |
KR (1) | KR100335569B1 (en) |
Cited By (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20050191947A1 (en) * | 2003-11-13 | 2005-09-01 | Chen Hung C. | Retaining ring with shaped surface |
US20050221733A1 (en) * | 2004-03-31 | 2005-10-06 | Fujikoshi Machinery Corp. | Polishing apparatus |
CN102172887A (en) * | 2011-02-16 | 2011-09-07 | 清华大学 | Polishing head |
US20170106497A1 (en) * | 2015-10-14 | 2017-04-20 | Ebara Corporation | Substrate holding device, substrate polishing apparatus, and method of manufacturing the substrate holding device |
US11260500B2 (en) * | 2003-11-13 | 2022-03-01 | Applied Materials, Inc. | Retaining ring with shaped surface |
CN114505782A (en) * | 2020-11-17 | 2022-05-17 | 长鑫存储技术有限公司 | Fixing device and detection system |
CN114952610A (en) * | 2021-11-10 | 2022-08-30 | 华海清科股份有限公司 | Bearing head for chemical mechanical polishing and polishing equipment |
CN115106932A (en) * | 2021-11-10 | 2022-09-27 | 华海清科股份有限公司 | Chemical mechanical polishing head and polishing equipment |
WO2024025792A1 (en) * | 2022-07-27 | 2024-02-01 | Applied Materials, Inc. | Minimizing substrate bow during polishing |
Families Citing this family (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE10247180A1 (en) * | 2002-10-02 | 2004-04-15 | Ensinger Kunststofftechnologie Gbr | Retaining ring for holding semiconductor wafers in a chemical mechanical polishing device |
KR101395553B1 (en) * | 2013-04-18 | 2014-05-15 | 주식회사 케이씨텍 | Chemical mechanical polishing apparatus which prevents wafer dechuck error and control method thereof |
KR102742729B1 (en) * | 2022-05-04 | 2024-12-16 | 주식회사 신강전기 | Motor housing processing methodb |
-
2000
- 2000-05-18 KR KR1020000026646A patent/KR100335569B1/en not_active Expired - Fee Related
-
2001
- 2001-05-03 US US09/847,292 patent/US20010053665A1/en not_active Abandoned
- 2001-05-14 JP JP2001143670A patent/JP2001358098A/en active Pending
Cited By (24)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US8585468B2 (en) | 2003-11-13 | 2013-11-19 | Applied Materials, Inc. | Retaining ring with shaped surface |
US9186773B2 (en) | 2003-11-13 | 2015-11-17 | Applied Materials, Inc. | Retaining ring with shaped surface |
WO2005049274A3 (en) * | 2003-11-13 | 2005-11-03 | Applied Materials Inc | Retaining ring with shaped surface |
US20220152778A1 (en) * | 2003-11-13 | 2022-05-19 | Applied Materials, Inc. | Retaining ring with shaped surface and method of forming |
US7344434B2 (en) | 2003-11-13 | 2008-03-18 | Applied Materials, Inc. | Retaining ring with shaped surface |
US7927190B2 (en) | 2003-11-13 | 2011-04-19 | Applied Materials, Inc. | Retaining ring with shaped surface |
US20230182261A1 (en) * | 2003-11-13 | 2023-06-15 | Applied Materials, Inc. | Method of forming retaining ring with shaped surface |
EP2191936A3 (en) * | 2003-11-13 | 2012-05-09 | Applied Materials, Inc. | Retaining ring with convex bottom surface |
US11260500B2 (en) * | 2003-11-13 | 2022-03-01 | Applied Materials, Inc. | Retaining ring with shaped surface |
US11850703B2 (en) * | 2003-11-13 | 2023-12-26 | Applied Materials, Inc. | Method of forming retaining ring with shaped surface |
US11577361B2 (en) * | 2003-11-13 | 2023-02-14 | Applied Materials, Inc. | Retaining ring with shaped surface and method of forming |
US9937601B2 (en) | 2003-11-13 | 2018-04-10 | Applied Materials, Inc. | Retaining ring with Shaped Surface |
US20050191947A1 (en) * | 2003-11-13 | 2005-09-01 | Chen Hung C. | Retaining ring with shaped surface |
US10766117B2 (en) | 2003-11-13 | 2020-09-08 | Applied Materials, Inc. | Retaining ring with shaped surface |
US20050221733A1 (en) * | 2004-03-31 | 2005-10-06 | Fujikoshi Machinery Corp. | Polishing apparatus |
US7247083B2 (en) * | 2004-03-31 | 2007-07-24 | Fujikoshi Machinery Corp. | Polishing apparatus |
CN102172887A (en) * | 2011-02-16 | 2011-09-07 | 清华大学 | Polishing head |
US10486284B2 (en) * | 2015-10-14 | 2019-11-26 | Ebara Corporation | Substrate holding device, and substrate polishing apparatus |
US11478895B2 (en) * | 2015-10-14 | 2022-10-25 | Ebara Corporation | Substrate holding device, substrate polishing apparatus, and method of manufacturing the substrate holding device |
US20170106497A1 (en) * | 2015-10-14 | 2017-04-20 | Ebara Corporation | Substrate holding device, substrate polishing apparatus, and method of manufacturing the substrate holding device |
CN114505782A (en) * | 2020-11-17 | 2022-05-17 | 长鑫存储技术有限公司 | Fixing device and detection system |
CN115106932A (en) * | 2021-11-10 | 2022-09-27 | 华海清科股份有限公司 | Chemical mechanical polishing head and polishing equipment |
CN114952610A (en) * | 2021-11-10 | 2022-08-30 | 华海清科股份有限公司 | Bearing head for chemical mechanical polishing and polishing equipment |
WO2024025792A1 (en) * | 2022-07-27 | 2024-02-01 | Applied Materials, Inc. | Minimizing substrate bow during polishing |
Also Published As
Publication number | Publication date |
---|---|
JP2001358098A (en) | 2001-12-26 |
KR20010105759A (en) | 2001-11-29 |
KR100335569B1 (en) | 2002-05-08 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
KR100385373B1 (en) | Semiconductor wafer polishing apparatus with a variable polishing force wafer carrier head | |
US7029382B2 (en) | Apparatus for chemical-mechanical polishing (CMP) head having direct pneumatic wafer polishing pressure | |
US6890402B2 (en) | Substrate holding apparatus and substrate polishing apparatus | |
EP1240977B1 (en) | Polishing apparatus | |
KR100874712B1 (en) | Board retainer | |
US6143127A (en) | Carrier head with a retaining ring for a chemical mechanical polishing system | |
KR19980071275A (en) | Semiconductor Wafer Polishing Equipment with Flexible Carrier Plate | |
KR20010033796A (en) | A carrier head with a removable retaining ring for a chemical mechanical polishing appartus | |
WO2001074534A2 (en) | A workpiece carrier with adjustable pressure zones and barriers | |
US20240017373A1 (en) | Membrane for carrier head with segmented substrate chuck | |
US20010053665A1 (en) | Polishing head of a chemical and mechanical polishing apparatus | |
WO2003032374A2 (en) | Workpiece carrier with adjustable pressure zones and barriers | |
US6533646B2 (en) | Polishing head with removable subcarrier | |
US6517421B2 (en) | Polishing head of a chemical and mechanical polishing apparatus for polishing a wafer | |
JP2004297029A (en) | Substrate holding device and polishing apparatus | |
US20020177395A1 (en) | Polishing head of a chemical and mechanical polishing apparatus for polishing a wafer | |
KR100419135B1 (en) | Apparatus and method for chemical-mechanical polishing (cmp) using a head having direct pneumatic wafer polishing pressure system | |
US6848981B2 (en) | Dual-bulge flexure ring for CMP head | |
KR20030055840A (en) | Polishing head of chemical and mechanical polishing apparatus | |
KR100553704B1 (en) | Chemical mechanical polishing apparatus and polishing pad used therein | |
KR20040017126A (en) | Polishing head of chemical and mechanical polishing apparatus |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
AS | Assignment |
Owner name: SAMSUNG ELECTRONICS CO., LTD., KOREA, REPUBLIC OF Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:LEE, SANG-YEOUL;KIM, KYUNG-DAE;KIM, HEE-DUK;AND OTHERS;REEL/FRAME:011785/0620;SIGNING DATES FROM 20010419 TO 20010420 |
|
STCB | Information on status: application discontinuation |
Free format text: ABANDONED -- FAILURE TO RESPOND TO AN OFFICE ACTION |