International Conference on Planarization/CMP Technology · October 25 – 27, 2007 Dresden
`VDE VERLAG GMBH · Berlin-Offenbach
`
`The Organic Diamond Disk (ODD)
`for Dressing Polishing Pads of Chemical Mechanical Planarization
`
`James C. Sung*,1,2,3, Cheng-Shiang Chou1, Yang-Liang Pai1, Michael Sung4
`
`1 KINIK Company, 64, Chung-San Rd., Ying-Kuo, Taipei Hsien 239, Taiwan, R.O.C.
`2 National Taiwan University, Taipei 106, Taiwan, R.O.C.
`3 National Taipei University of Technology, Taipei 106, Taiwan, R.O.C.
`4 Advanced Diamond Solutions, Inc., 351 King Street Suite 813, San Francisco, CA 94158,
`U.S.A.
`
`E-mail: sung@kinik.com.tw
`
`Diamond pad conditioners can determine the efficiency of CMP processes and the
`quality of polished wafers. The polishing rate of a wafer is dependent on the amplitude
`(height) of pad asperities. The polishing uniformity is controlled by the frequency
`(density) of such asperities. Current diamond pad conditioners cannot dress the pad to
`produce microns sized asperities at high density. This is because the tips of diamond
`grits cannot be leveled to the same height so the grooved pad top is uneven with
`excessive asperities that may ruin the wafer and under sized asperities that is easily
`glazed.
`
`New designs of diamond pad conditioners have markedly improved the leveling of
`diamond tips. Organic diamond disks (ODD) are manufactured by reverse casting of
`polymers. Due to the uniform spacing of diamond grits and their controlled tip heights,
`none of the diamond grits will be overly stressed. Moreover, all diamond grits are
`sharing the dressing work. Consequently, the number of working grits of ODD is
`significantly higher than conventional designs. Moreover, because no diamond will cut
`pad unnecessarily, the pad life is greatly lengthened. Furthermore, due to the uniform
`distribution of pad asperities, the slurry will be held efficiently so the run off is avoided.
`As a result, the slurry usage is reduced. ODD is therefore a significant savor of CMP
`consumables for semiconductor manufacture.
`
`Keywords: CMP, Diamond Dresser, Pad Conditioner, Epoxy
`
`1. Organic Diamond Disks
`
`Conventional CMP pad conditioners are made by bonding individual diamond grits with a
`metal matrix on a flat metal substrate. Due to the variation of grit sizes and diamond orientation,
`the tip height distribution is intrinsically large (50-100 microns). Hence, the cutting depth of
`the pad varies significantly. The deep grooving of the tall grits cannot only overly consume the
`pad, but also the diamond will be excessively stressed. The diamond may be chipped by such
`impact force, particularly if it was thermally damaged during the manufacturing process, as in
`the case of vacuum brazing or hot pressing. Even if the diamond is not weakened by heating,
`the high stress may pullout the diamond from the matrix, particularly if the bonding strength is
`weak, as in the case of electroplated pad conditioners.
`
`A new design by reversing the diamond attaching process is made with an organic matrix (e.g.
`
`Authorized licensed use limited to: Ingrid Hsieh-Yee. Downloaded on February 09,2024 at 22:04:05 UTC from IEEE Xplore. Restrictions apply.
`
`IPR2024-00534
`Samsung Electronics Co. Ltd. et al v. Chien-Min Sung
`Samsung's Exhibit 1019
`Ex. 1019, Page 1
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`

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`International Conference on Planarization/CMP Technology · October 25 – 27, 2007 Dresden
`VDE VERLAG GMBH · Berlin-Offenbach
`
`epoxy). The diamond grits are first leveled to a mold surface. Subsequently, they are cast by
`covering with a polymer. Due to the pre-leveling of the diamond tips, their height variation is
`within 20 microns. This organic diamond disk (ODD) will dress pad uniformly without
`excessive cutting. The result is a significant increase of pad life. In addition, the reverse
`casting process allows the use of larger diamond so the buried portion in the matrix is many
`times more than the protruded one. As no diamond grit is overly stressed, there is no risk of
`falling out grits. Because the fabrication process is at ambient temperature so the diamond
`strength is fully preserved to avoid chipping during the dressing process.
`
`ODD disks are very light (e.g. 70 grams) and they can be transparent or color-coded. This
`versatility can make their inspections easier (e.g. to check the loss diamond) and also for the
`color management of CMP manufacture with different recipes (e.g. red disks for copper
`removal and black ones for oxide polishing). In contrast, conventional pad conditioners are
`made of heavy (e.g. 430 grams) metal and their appearances are the same for various designs.
`
`Fig. 1: The monolithic ODD (left diagram) and the layered metal pad conditioner (right
`diagram).
`
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`Ex. 1019, Page 2
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`

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`International Conference on Planarization/CMP Technology · October 25 – 27, 2007 Dresden
`VDE VERLAG GMBH · Berlin-Offenbach
`
`Fig. 2: Transparent ODD can allow defects (e.g. missing diamond) be spotted with naked eyes.
`
`2. The Design Features
`
`The bonding of diamond by epoxy resin is weak compared to metal bonding. However,
`because the diamond tips are leveled to a much tighter range, the distribution of the dressing
`stresses is much more uniform. Mover over, the burial depth for each diamond is about twice
`that of the exposed portion. Consequently, the risk of plucking away a diamond from the matrix
`during dressing the pad in minimal.
`
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`Ex. 1019, Page 3
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`

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`International Conference on Planarization/CMP Technology · October 25 – 27, 2007 Dresden
`VDE VERLAG GMBH · Berlin-Offenbach
`
`Fig. 3: The bonding conditions of diamond in the epoxy matrix.
`
`The dressing rate of the pad for ODD can be controlled by diamond to diamond separation, the
`higher the separation, the deeper the penetration to the pad, and the higher the dressing rate.
`Moreover, if shapes are less regular, the sharp cutting tips can increase the dressing rate.
`Furthermore, if more diamond tips are oriented facing the pad, the dressing rate can also be
`enhanced.
`
`Fig. 4: The diamond orientation effect on the dressing rate of ODD.
`
`The long dressing performance of ODD is comparable to the standard DiaGrid® pad
`conditioners made by brazing diamond with Ni-Cr alloy, although the decay rate may be slower.
`
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`Ex. 1019, Page 4
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`International Conference on Planarization/CMP Technology · October 25 – 27, 2007 Dresden
`VDE VERLAG GMBH · Berlin-Offenbach
`
`Fig. 5: The dressing rate of ODD is controllable and its decay rate is less than DiaGrid® pad
`conditioners (DG).
`
`3. Preliminary Results
`
`The prototype ODD samples were tested at Rohm-Haas, the leader of CMP consumables. The
`result indicate that the polishing performance of oxide wafer is comparable between ODD and
`the standard DiaGrid® pad conditioners. However, the asperities on the pad dressed by ODD
`are much more uniform.
`
`Fig. 6: The contrast of pad asperities distributions. Note that the spread of asperities heights of
`ODD was narrower than DiaGrid® pad conditioner (courtesy of RHEM-CMPT).
`
`The more benign dressing of ODD can result in much longer pad life that may reduce
`significantly the cost of consumables.
`
`The ODD and DiaGrid® samples were also compared with the wafer profiles when polished at
`different conditions. The results confirmed that ODD was fully capable to replace DiaGrid®
`pad conditioners for CMP manufacture of semiconductors.
`
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`Ex. 1019, Page 5
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`International Conference on Planarization/CMP Technology · October 25 – 27, 2007 Dresden
`VDE VERLAG GMBH · Berlin-Offenbach
`
`Fig. 7: Wafer (200 mm) profiles of ODD (upper curves) versus DiaGrid® pad conditioners
`(lower curves) for two different polishing conditions (courtesy of Eternal).
`
`Additional data has confirmed at semiconductor fabs that the pad dress rate is half or less for
`achieving the same wafer removal rate. Moreover, the dressing time can be shortened by about
`1/3 to restore the polishing effectiveness of the pad after polishing the wafer. These results
`imply that the CMP production pads will be consumed much less and the throughput of wafer
`passes can be increased significantly.
`
`4. Conclusions
`
`The major concern of using an organic matrix to hold diamond is that the adherence strength is
`weaker, about 5 times lower compared to a metallic matrix. However, this deficiency is made
`up by the tight height control of diamond tips. Conventional diamond disks are fabricated by
`laying diamond on a flat substrate so the diamond tip heights are dependent on the size
`distribution. In order to minimize the variation of diamond tips, smaller diamond crystals are
`used. As a result, the burry depth of small diamond is shallow. In contrast, ODD can bury deep
`without altering the tip positions, so the weak bonding strength is more than made up by
`increasing the bonding area. Moreover, because the tip heights are under stringent control, the
`loading of diamond tips is below the threshold limit that may pluck out a diamond.
`Consequently, it is less like to loss a diamond from an ODD dresser than a conventional
`metallic disk. Furthermore, ODD is processed at room temperature so its diamond is not
`thermally degraded. In contrast, the brazed diamond disks contain vulnerable diamond grits
`that may break during the CMP process.
`
`ODD has much higher count of working crystals so its life is significantly longer. Moreover,
`being benign in dressing, ODD is actually a pad saver. In addition, ODD can create densely
`populated pad asperities that can polish wafers fast but with high uniformity. Hence, ODD
`cannot only reduce the CMP cost, but also improve the wafer quality.
`
`References
`
`[1] Chien-Min Sung, “Diamond Tools with Diamond Grits Set in a Predetermined Pattern”,
`2006 Powder Metallurgy World Congress, Bexco, Busan, Korea, p881-882.
`[2] Chien-Min Sung, “Chemical Mechanical Polishing Pad Dresser”, Taiwan Patent No.
`I264345.
`[3] Chien-Min Sung, “Chemical Mechanical Polishing Pad Dresser”, U.S. Patent Publication
`No. 20060143991.
`[4] Chien-Min Sung, “Methods of Bonding Superabrasive Particles in An Organic Matrix”, U.S.
`patent application filed in 2005.
`
`Authorized licensed use limited to: Ingrid Hsieh-Yee. Downloaded on February 09,2024 at 22:04:05 UTC from IEEE Xplore. Restrictions apply.
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`Ex. 1019, Page 6
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