Dual-dosing polishing composition for glass substrates

Abstract

The present invention provides improved polishing compositions and methods for polishing memory or rigid disks. [Solution] A chemically mechanical polishing composition is provided, comprising or substantially comprising a liquid carrier, abrasive particles within the liquid carrier, a pyrophosphate compound, and a sulfonate compound or a compound containing a quaternary ammonium group.

Description

Technical Field

[0001] The embodiments disclosed herein relate to a chemical mechanical polishing composition for polishing a glass substrate, and more particularly to a composition comprising a pyrophosphate compound and a sulfonate compound or a quaternary amine.

Background Art

[0002] In the hard disk drive industry, there is a continuing need for increased storage capacity and miniaturization. This has led to a corresponding demand for smaller memories or rigid disks with higher storage (or data) density, and an improved process is needed to polish such memories or rigid disks.

[0003] As used herein, the term "memory or rigid disk" refers to any magnetic disk, hard disk, rigid disk, or memory disk used to hold information in electromagnetic form. These memories or rigid disks are herein simply referred to as disks or substrates and generally fall into one of two types: (i) nickel-phosphorus plated aluminum disks, or (ii) glass disks. During manufacture, these disks are polished to strict surface finish tolerances and then a magnetic material for final data storage is deposited thereon.

[0004] As is well known, the data storage industry is continuously, and sometimes extremely, subject to price reduction pressures. To maintain an economically favorable process, generally high throughput is required, which in turn requires a high material removal rate during the polishing operation. However, increasing the removal rate increases the surface roughness or surface waviness.

[0005] While chemical mechanical polishing (CMP) compositions and methods for polishing nickel-phosphorus and / or glass discs are commercially available, there is an unmet demand for improved polishing compositions to enhance processing capacity and enable increased storage density. In particular, there is an unmet demand for polishing compositions that provide improvements in surface finish (e.g., reduction of surface roughness and surface waviness) and high material removal rates.

[0006] Summary of the Invention A chemically mechanical abrasive composition is disclosed. The composition comprises, or substantially comprises, a liquid carrier; abrasive particles within the liquid carrier; a pyrophosphate compound; and a sulfonate anionic surfactant or a sulfonate compound containing polysulfonic acid.

[0007] In another embodiment, the disclosed abrasive composition comprises, or substantially comprises, a liquid carrier; abrasive particles within the liquid carrier; a pyrophosphate compound; and a cationic compound containing a quaternary ammonium cation.

[0008] Detailed description of the invention A chemically mechanical abrasive composition is disclosed. The composition comprises, or substantially comprises, a liquid carrier, abrasive particles within the liquid carrier, a pyrophosphate compound, and a sulfonate anionic surfactant, or an anionic polymer containing a sulfonic acid group, or a compound containing a quaternary ammonium group. In certain embodiments, the composition comprises, or substantially comprises, a liquid carrier, abrasive particles within the liquid carrier, and a synergistic combination of a pyrophosphate compound and a sulfonate anionic surfactant, or an anionic polymer containing a sulfonic acid group, or a synergistic combination of a pyrophosphate compound and a compound containing a quaternary ammonium group.

[0009] While the disclosed embodiments are not limited in this respect, the disclosed compositions are advantageously usable for polishing glass substrates (e.g., those used in the construction of memory or rigid disks in hard disk drives). As will be illustrated in more detail below, the disclosed polishing compositions include synergistic combinations of chemical additives, which have been found to advantageously result in a significant improvement in polishing speed. Certain embodiments of the disclosed embodiments have also been found to result in equivalent or even improved surface finishes (e.g., surface undulation).

[0010] It will be understood that the term “synergistic” (or “synergistic effect”) is used in accordance with the definition of the term in standard dictionaries. Synergy is defined as the interaction of multiple elements such that the combined effect is greater than the sum of their individual effects (Dictionary of Science and Technology, Academic Press, 1992). In the disclosed embodiments, it has been found that combinations of pyrophosphate compounds with sulfonate compounds (e.g., disulfonate anionic surfactants) or with quaternary ammonium compounds increase the removal rate in polishing glass substrates beyond the sum of the individual contributions of the pyrophosphate and sulfonate compounds. Furthermore, as will be described in detail in the following examples, it has been found that the addition of sulfonate compounds or quaternary ammonium compounds to compositions containing pyrophosphate compounds unexpectedly increases the removal rate (contrary to what was expected to decrease the removal rate).

[0011] The disclosed polishing compositions generally contain polishing particles dispersed or suspended in a liquid carrier. The liquid carrier is used to facilitate the application of the polishing particles and chemical additives to the surface of the substrate to be polished. The liquid carrier may contain any suitable carrier (e.g., a solvent), which may include lower alcohols (e.g., methanol, ethanol, etc.), ethers (e.g., dioxane, tetrahydrofuran, etc.), water, and mixtures thereof. The liquid carrier is preferably composed of or substantially composed of deionized water.

[0012] The disclosed abrasive compositions may include abrasive particles in a liquid carrier (e.g., dispersed or suspended in a liquid carrier). The abrasive particles may include substantially any abrasive particles suitable for polishing glass substrates, such as metal oxide particles, diamond particles, and / or ceramic particles. Metal oxide particles may include, for example, silica, ceria, and / or alumina abrasive particles (including colloidal and / or fumed metal oxide particles). Ceramic particles may include materials such as cubic boron nitride or silicon carbide.

[0013] Preferred embodiments include silica abrasive particles, such as fumed silica or colloidal silica abrasive particles. As used herein, the term colloidal silica particles refers to silica particles produced by a wet process. Colloidal silica may be precipitated silica or condensation-polymerized silica, which can be produced by methods known to those skilled in the art (e.g., by the sol-gel method or silicate ion exchange). Condensation-polymerized silica particles are often produced by condensing Si(OH)4 to form substantially spherical particles. Fumed silica is obtained by exothermic or flame hydrolysis processes (reacting silicon tetrachloride with oxygen in a flame) and generally has an aggregate structure, in which substantially spherical primary particles are fused together to form a chain-like aggregate.

[0014] Abrasive particles (e.g., colloidal silica particles) can have virtually any suitable particle size. The particle size of particles suspended in a liquid carrier can be defined industrially by various means. For example, particle size can be defined as the diameter of the smallest sphere surrounding the particle, and can be measured by various commercially available instruments, including, for example, the CPS Disc Centrifuge, Model DC24000HR (manufactured by CPS Instruments, Inc., Prairieville, Louisiana, USA), or the Zetasizer® from Malvern Instruments®. Abrasive particles may have an average particle size of about 5 nm or more (e.g., about 10 nm or more, about 15 nm or more, or about 20 nm or more). Abrasive particles may have an average particle size of about 100 nm or less (e.g., about 50 nm or less, about 45 nm or less, or about 40 nm or less). Therefore, the colloidal silica particles may have an average particle size in the range of about 5 nm to about 50 nm (e.g., about 10 nm to about 40 nm, about 15 nm to about 40 nm, or about 20 nm to about 40 nm). For example, in one advantageous embodiment, the polishing particles include colloidal silica with an average particle size of about 30 nm.

[0015] The abrasive composition may contain the above-mentioned abrasive particles in any appropriate amount. For example, the abrasive particles may be present in an amount of about 1% by weight or more (e.g., about 2% by weight or more, about 3% by weight or more, or about 5% by weight or more) at the time of use. The amount of abrasive particles in the abrasive composition may be about 20% by weight or less (e.g., about 15% by weight or less, about 12% by weight or less, or about 10% by weight or less) at the time of use. Thus, it is understood that the amount of abrasive particles may be within a range delimited by any two of the above endpoints, which is, for example, in the range of about 1% by weight to about 20% by weight at the time of use (e.g., about 2% by weight to about 20% by weight, about 5% by weight to about 15% by weight, about 5% by weight to about 12% by weight, or about 5% by weight to about 10% by weight). For example, in one advantageous embodiment, the abrasive composition may contain about 8.5% by weight of colloidal silica at the time of use.

[0016] The disclosed abrasive compositions further comprise pyrophosphate compounds. As used herein, the term pyrophosphate compound refers to a compound comprising a phosphorus anion having two phosphorus atoms in the POP bond. Pyrophosphate compounds will generally be understood in the chemical field to be called diphosphates or diphosphate compounds (presumably because the phosphorus anion contains two phosphorus atoms). The disclosed embodiments may comprise substantially any suitable pyrophosphate compound, including, for example, disodium pyrophosphate (DSPP), tetrasodium pyrophosphate (TSPP), dipotassium pyrophosphate (DKPP), and tetrapotassium pyrophosphate (TKPP). Preferred pyrophosphate compounds include TSPP and TKPP.

[0017] The abrasive composition may contain the above-mentioned pyrophosphate compound in substantially any suitable amount. For example, the abrasive composition may contain about 0.001% by weight (10 ppm by weight) or more of the pyrophosphate compound at the time of use (e.g., about 0.01% by weight or more, or about 0.02% by weight or more). The amount of the pyrophosphate compound in the abrasive composition may be about 1% by weight or less at the time of use (e.g., about 0.5% by weight or less, about 0.3% by weight or less, or about 0.2% by weight or less). Thus, it is understood that the amount of the pyrophosphate compound may be within a range delimited by any two of the above endpoints, which is, for example, in the range of about 0.001% by weight to about 1% by weight at the time of use (e.g., about 0.01% by weight to about 0.5% by weight, about 0.01% by weight to about 0.3% by weight, about 0.02% by weight to about 0.3% by weight, or about 0.02% by weight to about 0.2% by weight). For example, in certain advantageous embodiments, the abrasive composition may contain about 0.03% by weight, 0.06% by weight, 0.08% by weight, or about 0.12% by weight of TKPP when in use.

[0018] The disclosed polishing compositions may further include a second additive compound (in addition to the pyrophosphate compound). The second additive compound may contain either (i) a sulfonate compound containing a sulfonate anionic surfactant, or an anionic polymer containing a sulfonic acid group, or (ii) a compound containing a quaternary ammonium group (hereinafter also referred to here as a quaternary amine or quaternary ammonium compound). As will be described in more detail in the following examples, the combination of the pyrophosphate compound and the second additive compound may be a synergistic combination that advantageously significantly increases the removal rate during polishing and also improves the surface finish of the polished substrate.

[0019] In certain embodiments, the second additive compound may contain substantially any suitable anionic surfactant or anionic polymer (polysulfonic acid) containing a sulfonic acid group. For example, suitable sulfonate anionic surfactants may include alkylaryl sulfonates (e.g., alkylbenzene sulfonates, e.g., dodecylbenzene sulfonate), alkyl sulfonates (e.g., alkenyl sulfonates, e.g., α-olefin sulfonates, alkyl glyceride sulfonates, alkyl ether sulfonates, and alkyl sulfoacetates), alkyl diphenyl oxide sulfonates, sulfosuccinates (e.g., monoalkyl sulfosuccinates, and dialkyl sulfosuccinates), acyl taurates, and acyl isethionates.

[0020] In certain preferred embodiments, the sulfonate anionic surfactant includes a disulfonate anionic surfactant, which is, for example, an alkyldiphenyl oxide disulfonate anionic surfactant having the following structure: TIFF2026076195000001.tif31170

[0021] In the formula, R is C1~C 30 Preferably C6~C 30 , futur C6~C 22A linear or branched, saturated or unsaturated alkyl group, wherein the alkyl group optionally contains one or more heteroatoms selected from the group consisting of O and N, and X + is either H or a cation, such as an alkali metal cation or an alkaline earth metal cation (e.g., sodium, potassium, lithium, calcium, magnesium, etc.). Examples of suitable alkyldiphenyl oxide disulfonate surfactants include those commercially available from Dow Chemical Company (Midland, Mich.) under the trade names Dowfax® 2A1, Dowfax® 3B2, Dowfax® 8390, Dowfax® C6L, Dowfax® C10L, and Dowfax® 30599.

[0022] Non-limiting examples of polymers or copolymers containing sulfonic acid groups include polystyrene sulfonic acid, polyvinyl sulfonic acid (PVSA), poly(2-acrylamido-2-methylpropanesulfonic acid), poly(styrene sulfonic acid-co-maleic acid), and poly(acrylic acid)-co-poly(2-acrylamido-2-methylpropanesulfonic acid).

[0023] In embodiments comprising a sulfonate anionic surfactant or a polysulfonic acid, the composition may contain the second additive compound in substantially any suitable amount. For example, the polishing composition may contain the second additive compound at about 0.001 wt% (10 ppm by weight) or more (e.g., about 0.01 wt% or more, or about 0.02 wt% or more) during use. The amount of the second additive compound in the polishing composition may be about 1 wt% or less (e.g., about 0.5 wt% or less, about 0.3 wt% or less, or about 0.2 wt% or less) during use. Thus, it is understood that the amount of the second additive compound may be in a range delimited by any two of the above end values, which may be, for example, about 0.001 wt% to about 1 wt% (e.g., about 0.01 wt% to about 0.5 wt%, about 0.01 wt% to about 0.3 wt%, about 0.02 wt% to about 0.3 wt%, or about 0.02 wt% to about 0.2 wt%) during use. For example, in certain advantageous embodiments, the polishing composition may contain about 0.05 wt% of Dowfax® 2A1, Dowfax® 3B2, Dowfax® C6L, or Dowfax® C10L during use.

[0024] The disclosed embodiments comprising a sulfonate anionic surfactant or a polysulfonic acid may further optionally contain an anionic (or another anionic) polymer, which includes, for example, poly(acrylic acid) (PAA), poly(methacrylic acid) (PMAA), poly(maleic acid) (PMA), and the like. By using such polymers in the polishing composition, advantageously, the friction during the polishing operation can be controlled and the undulation of the substrate can be reduced. Such polymers do not interact synergistically with pyrophosphate compounds and / or sulfonate compounds. Exemplary compositions may contain such optional anionic polymers at about 0 to about 1000 ppm by weight (e.g., about 30 to about 300 ppm by weight of PAA or PMAA in certain embodiments).

[0025] As used herein, the term "sulfonate" is understood to refer to the ionized (anionic) form of a surfactant (or polymer) (containing at least one anionic oxygen), and is also understood to refer to the acid form of a surfactant (containing at least one OH group of an acid). As is well known in the chemical art, the acid forms of many sulfur-based surfactants generally have a high acidity and tend to be ionized even at relatively low pH values (e.g., pH 2-3). Thus, the anionic surfactant in the CMP composition of the present invention can generally exist mainly in anionic form, regardless of whether the surfactant is added to the composition in the form of a salt or in acid form.

[0026] In certain other embodiments, the second additive compound can include substantially any suitable quaternary amine (i.e., substantially any suitable compound containing a quaternary ammonium group). Such compounds can be represented by the following chemical formula: --N + R’R’ ’R’ ’ ’ wherein R’, R’ ’, and R’ ’ ’ can be the same or different and can include substantially any carbon-containing compound. It is understood that the n-ium group in the quaternary ammonium can have a structure corresponding to the structure of a tertiary amine as a raw material. For example, when the tertiary amine is triethylamine, the corresponding quaternary ammonium group is triethylammonium. The quaternary ammonium group can be, for example, one having a saturated hydrocarbon group (e.g., trimethylamine, triethylamine, dimethylethylamine, etc.), a hydroxy group, an ether group, an amino group, and / or one having a hydrocarbon group with an unsaturated carbon bond (e.g., dimethylethanolamine, dimethylaniline, diethylaniline, dimethylbenzylamine, pyridine, etc.).

[0027] In preferred embodiments, the compound containing a quaternary ammonium group includes a tetramethylammonium group, a tetraethylammonium group, a tetrabutylammonium group, a benzyltributylammonium group, or a mixture thereof. In most preferred embodiments, the compound contains tetraethylammonium hydroxide.

[0028] In embodiments comprising a compound having a quaternary ammonium group, the composition may contain the compound in substantially any suitable amount. For example, the abrasive composition may contain the compound in about 0.001% by weight (10 ppm by weight) or more (e.g., about 0.01% by weight or more, or about 0.02% by weight or more) at the time of use. The amount of the compound in the abrasive composition may be about 0.5% by weight or less (e.g., about 0.4% by weight or less, about 0.3% by weight or less, or about 0.2% by weight or less) at the time of use. Thus, it is understood that the amount of the compound may be in a range delimited by any two of the above endpoints, which is, for example, in the range of about 0.001% by weight to about 0.5% by weight at the time of use (e.g., about 0.01% by weight to about 0.5% by weight, about 0.01% by weight to about 0.4% by weight, about 0.002% by weight to about 0.3% by weight, or about 0.002% by weight to about 0.2% by weight). For example, in certain advantageous embodiments, the abrasive composition may contain tetraethylammonium hydroxide at the time of use in an amount of about 0.02% by weight, 0.05% by weight, 0.1% by weight, or 0.2% by weight.

[0029] The disclosed abrasive compositions are generally acidic, with a pH less than about 7. The pH is, for example, greater than about 1 (e.g., greater than about 1.5). The pH may be less than about 5 (e.g., less than about 4, less than about 3.5, or less than about 3). Therefore, it is understood that the pH of the abrasive composition may be within a range delimited by any two of the above endpoints, which is, for example, in the range of about 1 to about 5 (e.g., about 1 to about 4, about 1.5 to about 3, or about 1.5 to about 3). For abrasive compositions containing pyrophosphate compounds and sulfonate compounds, the pH may preferably be in the range of about 1.5 to about 2. For abrasive compositions containing pyrophosphate compounds and quaternary amines, the pH may most preferably be in the range of about 2 to about 3.

[0030] The pH of the abrasive composition can be achieved and / or maintained by any suitable means. The abrasive composition may contain substantially any suitable pH adjuster or buffer system known to those skilled in the chemical art. For example, suitable pH adjusters may include various acids, including nitric acid, sulfuric acid, and phosphoric acid.

[0031] The disclosed abrasive compositions may include substantially any additional, optional chemical additives. For example, the disclosed compositions may further include one or more dispersants and / or biocides. Such additional additives are purely optional. The disclosed embodiments are not limited thereto, and it is not necessary to use one or more such additives. In further embodiments including a biocide, the biocide may include any suitable biocide.

[0032] Abrasive compositions can be manufactured using any suitable technique, many of which are known to those skilled in the art. Abrasive compositions can be manufactured in batch processes or in continuous processes. Generally, abrasive compositions can be manufactured by combining the components of the composition in any order. As used herein, the term “component” includes each component (e.g., colloidal silica, pyrophosphate, and a second additive compound).

[0033] For example, the components of the abrasive composition may be added directly to a dispersion containing abrasive particles. Alternatively, the abrasive may be added to a solution containing a pyrophosphate and a second additive compound. In any case, the abrasive particles and the other components may be blended together by any suitable technique to achieve adequate mixing. Such blending / mixing techniques are well known to those skilled in the art.

[0034] The abrasive compositions of the present invention may also be provided as concentrates intended to be diluted with an appropriate amount of water before use. In such embodiments, the abrasive composition concentrate may contain an abrasive (e.g., silica), a pyrophosphate compound, a second additive compound, and any other optional compound, such that when the concentrate is diluted with an appropriate amount of water, each component of the abrasive composition is present in the abrasive composition in amounts within the appropriate ranges set forth above for each component. For example, colloidal silica and other optional components may each be present in the abrasive composition in amounts about twice (e.g., about three times, about four times, or about five times) greater than the concentrations used for each component as set forth above. This ensures that when the concentrate is diluted by equal volumes (e.g., equal volumes × 1 water, equal volumes × 2 water, equal volumes × 3 water, or equal volumes × 4 water), each component is present in the abrasive composition in amounts within the previously defined ranges for each component. Furthermore, as will be understood by those skilled in the art, the concentrate may contain an appropriate fraction of water present in the final abrasive composition to ensure that the other components are at least partially or completely dissolved in the concentrate.

[0035] The disclosed compositions can be advantageously used for polishing glass substrates, preferably rigid disk glass substrates. The disclosed compositions can be used in conjunction with a suitable polishing machine for polishing glass substrates (e.g., rigid disk glass substrates). Such a polishing machine generally comprises an upper platen and a lower platen and is configured to polish both sides of multiple substrates simultaneously. Each platen is fitted with a polishing pad, and these platens generally rotate independently in opposite directions.

[0036] During the polishing process, the substrate is loaded with one or more carriers that engage with internal and external gears located on the lower platen. The rotational speed of the carriers is controlled by controlling the rotation of the gears. The upper platen is lowered to contact the substrate, and the polishing composition is distributed to the substrate through the upper platen (and upper pad). The rotational speeds of the platen and carriers are selected so that the upper and lower sides of the substrate are polished at approximately the same speed.

[0037] The effectiveness of the polishing process can be characterized in several respects, such as the polishing removal rate and the surface roughness or surface waviness of the polished substrate. This removal rate can be determined, for example, by measuring the mass loss (weighing the substrate before and after polishing) and determining the amount of substrate removed per unit time of polishing. Surface roughness can be evaluated in terms of mean roughness (Ra) or surface waviness (HMS_Wq) by, for example, a profiler (surface shape measuring instrument) or atomic force microscope (AFM) measurement, or by optical measurement techniques, such as using KLA Tencor's Candela 6100 or 6300 equipment.

[0038] The substrate may be polished with the disclosed composition using any suitable polishing pad. Suitable pads include, for example, woven or nonwoven polishing pads. Furthermore, suitable polishing pads may contain any suitable polymer having varying densities, hardness, thickness, compressibility, rebound ability upon compression, and compressive modulus. Suitable polymers include, for example, polyvinyl chloride, polyvinyl fluoride, nylon, fluorocarbon, polycarbonate, polyester, polyacrylate, polyether, polyethylene, polyamide, polyurethane, polystyrene, polypropylene, products formed with these, and mixtures thereof.

[0039] This disclosure is understood to include many embodiments, including, but not limited to, those listed in the claims.

[0040] The present invention will be further illustrated by the following embodiments, but of course, this should not be considered to limit the scope of the invention in any way.

[0041] Example 1 This example demonstrates the synergistic combination of pyrophosphate compounds and sulfonate anionic surfactants in the disclosed polishing compositions. Each polishing composition contains 8.5% by weight of colloidal silica with an average particle size of 30 nm and sufficient nitric acid to adjust the pH to 1.8. Polishing composition 1A contains no other components. Polishing compositions 1B to 1I further contain tetrapotassium pyrophosphate (TKPP) and / or alkyldiphenyl oxide disulfonate anionic surfactant (DOWFAX® C10L) in the amounts shown in Table 1 (all amounts are by weight percent).

[0042] Six separate glass disks (substrates) were polished using each composition (all six disks were polished simultaneously in each trial). The trial was conducted using a Hamai 9B double-sided polishing tool with a lower platen speed of 60 rpm, carrier rotation speed of 20 rpm, carrier rotation speed of 12 rpm, and a downforce of 33 g / m. 2 The process was carried out for 11 minutes at a slurry flow rate of 600 ml / min. The polishing rate was determined based on mass loss, and the surface waviness (HMS_Wq) was determined for two of the six discs using the Candela 6100 measuring tool. The results for removal rate and surface waviness are shown in Table 1. These results are normalized to the removal rate and surface waviness achieved using polishing composition 1A. TIFF2026076195000002.tif129170

[0043] As shown in Table 1, adding disulfonate surfactants (1B and 1C) to the base composition (1A) improved surface waviness at the expense of a decrease in removal rate (wavy decreased to 76 and 66 at the expense of a decrease in removal rate to 85 and 73 at normalized values). Adding pyrophosphates (1D, 1E, 1F, 1G, and 1H) to the base composition (1A) increased the removal rate, albeit at the expense of an increase in surface waviness (as the TKPP concentration increased, the removal rate increased to 115, 130, 138, 152, and 151 at the expense of an increase in waviness to 110, 115, 115, 120, and 121 at normalized values).

[0044] An unpredictable synergistic interaction was observed for composition 1I, where the addition of a disulfate surfactant to the composition containing the pyrophosphate compound significantly improved both the removal rate and surface undulation. Comparing the results for composition 1I with those for 1F, the addition of the disulfate surfactant increased the removal rate to 138–155 (normalized value) and decreased the undulation to 115–107 (normalized value). The further improvements in removal rate were unpredictable (as a decrease in removal rate was observed with the addition of the disulfate surfactant in compositions 1B and 1C) and were synergistic. If the combination of pyrophosphate and disulfate anionic surfactant were merely an additive (or less), the maximum removal rate for composition 1I would be predicted to be 111 (an increase of 38 and a decrease of 27, for a net increase of 11). Therefore, the observed removal rate of 155 is clear evidence of a synergistic effect.

[0045] Example 2 This example further demonstrates the synergistic combination of pyrophosphate compounds and anionic sulfonate surfactants in the disclosed polishing compositions, as well as the effects of optional anionic polymer additives. Each polishing composition contains 8.5% by weight colloidal silica with an average particle size of 30 nm and sufficient nitric acid to adjust the pH to 1.8. Polishing compositions 1C, 1G, and 1I were as previously described in Example 1. Polishing compositions 2A to 2G further contained TKPP and / or DOWFAX® C10L in the amounts shown in Table 2 (all amounts are weight percent). Compositions 2A to 2G also further contained 0.01% by weight (100 ppm by weight) of polyacrylic acid with a molecular weight of 250,000 g / mol.

[0046] Six separate glass disks (substrates) were polished using each composition under the polishing conditions described earlier in Example 1, with a double-sided polishing tool, Hamai 9B. The polishing speed and surface waviness HMS_Wq were also determined as described earlier in Example 1. The results for removal speed and surface waviness are shown in Table 2. These results were normalized to the removal speed and surface waviness achieved using polishing composition 1A, as reported in Table 1. TIFF2026076195000003.tif148170

[0047] As shown in Table 2, it was observed that the addition of PAA reduced surface waviness and removal rate. In the absence of TKPP, adding PAA to compositions containing a disulfonate surfactant (comparison of compositions 2A to 1C) reduced the removal rate to 73 to 72 (normalized value) and the waviness to 66 to 60 (normalized value). PAA did not participate in or interfere with the synergistic effect with the pyrophosphate compound and the disulfonate surfactant. In compositions containing a synergistic combination of TKPP and a disulfonate surfactant, the addition of PAA (comparison of compositions 2B and 1I) reduced the removal rate to 155 to 154 (normalized value) and the waviness to 107 to 102 (normalized value).

[0048] The synergistic interaction between the pyrophosphate compound and the disulfonate surfactant was further observed in compositions 2C to 2G. Here, the addition of the disulfonate surfactant to the composition containing TKPP significantly improved both the removal rate and surface undulation. Comparing compositions 2C to 2F with composition 1G, it was observed that as the concentration of the disulfonate surfactant increased, the removal rate increased from a normalized value of 152 to 156, 163, 174, and 185, while the surface undulation decreased from a normalized value of 120 to 117, 109, 106, and 102.

[0049] Example 3 This example demonstrates that the synergistic interaction described above was not observed for polishing compositions containing other phosphate compounds (in other words, the synergistic interaction was observed only for compositions containing pyrophosphate compounds). As described in Example 1, each composition contains 8.5% by weight of colloidal silica with an average particle size of 30 nm and sufficient nitric acid to adjust the pH to 1.8. Polishing compositions 1G and 2E are as previously described in Examples 1 and 2. Polishing compositions 3A and 3B further contained 0.093% by weight of hydroxyethylidene diphosphinic acid (HEDP), compositions 3C and 3D further contained 0.259% by weight of diethylenetriaminepenta(methylenephosphonic acid) (DTPMPA), compositions 3E and 3F further contained 0.122% by weight of 2-phosphonobutane 1,2,4-tricarboxylic acid (PBTC), and polishing compositions 3G and 3H further contained 0.5% by weight of tartaric acid (carboxylic acid). Note that the molar concentrations of the phosphate or carboxylic acid additives were the same for compositions 1G, 2E, and 3A-3H. Compositions 1G, 3B, 3D, 3F, and 3H further contained 0.05% by weight of alkyldiphenyl oxide disulfonate surfactant (DOWFAX® C10L). The amounts of the additives are listed in Table 3.

[0050] Six separate glass disks (substrates) were polished using each composition under the polishing conditions previously described in Example 1, with a double-sided polishing tool, Hamai 9B. The polishing speed and surface waviness HMS_Wq were also determined as previously described in Example 1. The results for removal rate and surface waviness are shown in Table 3. These results were normalized to the removal rate and surface waviness achieved using polishing composition 1A, as reported in Table 1. TIFF2026076195000004.tif149170

[0051] As shown in Table 2, the synergistic effect previously observed in Examples 1 and 2 was observed only for compositions containing pyrophosphate compounds (comparing compositions 1G and 2E, previously described in Example 2). No synergistic effect was observed for compositions containing other phosphonates and carboxylic acid additives. Adding a disulfate anionic surfactant to a composition containing HEDP (comparing 3A and 3B) resulted in a decrease in removal rate and undulation (the removal rate decreased to 136-116 on a normalized basis, while the undulation decreased to 108-95 on a normalized basis). Adding a disulfate anionic surfactant to a composition containing DTPMPA (comparing 3C and 3D) resulted in a decrease in removal rate and undulation (the removal rate decreased to 151-128 on a normalized basis, while the undulation decreased to 107-101 on a normalized basis). When a disulfonate anionic surfactant was added to a composition containing PBTC (comparing 3E and 3F), a decrease in removal rate and waviness was observed (the removal rate decreased to 181-114 on a normalized basis, while the waviness decreased to 132-95 on a normalized basis). When a disulfonate anionic surfactant was added to a composition containing tartaric acid (comparing 3G and 3H), a decrease in removal rate and waviness was observed (the removal rate decreased to 138-129 on a normalized basis, while the waviness decreased to 116-100 on a normalized basis).

[0052] Example 4 This example demonstrates that the above synergistic effect was also observed in polishing compositions using other sulfonated surfactants (in addition to DOWFAX® C10L used in Examples 1 and 2). As previously described for Example 1, each polishing composition contained 8.5% by weight of colloidal silica with an average particle size of 30 nm and sufficient nitric acid to adjust the pH to 1.8. Polishing compositions 1F, 1G, 1I, and 2E were as previously described in Examples 1 and 2. Polishing compositions 4A-4D and 4F further contained 0.12% by weight of TKPP, while composition 4E further contained 0.08% by weight of TKPP. Polishing compositions 4A to 4F further contained 0.05% by weight of dodecylbenzenesulfonate (DDBS) (4A), DOWFAX® C6L (4B), DOWFAX® 3B2 (4C), DOWFAX® 2A1 (4D), polyvinyl sulfonic acid (PVSA) (4E), and DEQUEST® P9200 (modified polyacrylic acid) (4F). The amounts of these additives are listed in Table 4.

[0053] Six separate glass disks (substrates) were polished using each composition under the polishing conditions previously described in Example 1, with a double-sided polishing tool, Hamai 9B. The polishing speed and surface waviness HMS_Wq were also determined as previously described in Example 1. The results for removal rate and surface waviness are shown in Table 4. These results were normalized to the removal rate and surface waviness achieved using polishing composition 1A, as reported in Table 1. TIFF2026076195000005.tif149170

[0054] As shown in Table 4, the synergistic effect observed in Examples 1 and 2 was also observed in polishing compositions containing other sulfonate compounds. In Examples 4B, 4C, and 4D, the use of other disulfonate anionic surfactants in the TKPP-containing composition increased the removal rate from a normalized value of 152 to 178, 179, and 155, and simultaneously decreased the surface waviness from a normalized value of 120 to 109, 110, and 115. In Examples 4A and 4E, the addition of DDBS and PVSA to the TKPP-containing composition also improved the removal rate and waviness. In Example 4A, the removal rate remained almost the same (normalized values ​​of 153 and 152), while the surface undulation decreased from 120 to 105 (normalized value). In contrast, in Example 4E, the removal rate improved from 138 to 144 (normalized value), and the surface undulation decreased from 115 to 110 (normalized value). It was observed that the combination of the non-sulfonate compound (DEQUEST® P9200) and TKPP resulted in a decrease in surface undulation from 120 to 108 (normalized value) in exchange for a decrease in the removal rate from 152 to 120 (normalized value) (4F).

[0055] Example 5 This example demonstrates the synergistic combination of pyrophosphate compounds and quaternary amine compounds in the disclosed polishing compositions. Each polishing composition contains 8.5% by weight of colloidal silica with an average particle size of 30 nm and sufficient nitric acid to adjust the pH to 1.8 (however, compositions 5H and 5I contain sufficient nitric acid to adjust the pH to 2.3 and 2.8, respectively). Polishing compositions 1A and 1G are as previously described in Example 1. Compositions 5B to 5I further contain TKPP, while compositions 5A to 5I further contain tetraethylammonium hydroxide in the amounts listed in Table 5 (all amounts are by weight percentage).

[0056] Six separate glass disks (substrates) were polished using each composition under the polishing conditions previously described in Example 1, with a double-sided polishing tool, Hamai 9B. The polishing speed and surface waviness HMS_Wq were also determined as previously described in Example 1. The results for removal rate and surface waviness are shown in Table 5. These results were normalized to the removal rate and surface waviness achieved using polishing composition 1A, as reported in Table 1. TIFF2026076195000006.tif155170

[0057] As shown in Table 5, the addition of a quaternary amine compound (5A) (in the absence of TKPP) was observed to improve surface waviness at the expense of a decrease in the removal rate (the removal rate decreased to 82 in normalized terms, while the surface waviness decreased to 88 in normalized terms). As previously described in Example 1, the addition of pyrophosphate (1G) was observed to increase the removal rate at the expense of an increase in surface waviness (the removal rate increased to 152 in normalized terms, while the waviness also increased to 120 in normalized terms). Unexpected synergistic interactions were observed for compositions 5B, 5C, 5D, 5E, 5F, and 5G, where the addition of a quaternary amine (TEAH in this example) to the polishing composition containing the pyrophosphate compound significantly improved the removal rate. Compared to composition 1G, these compositions increased the removal rate to 168, 206, 211, 207, 205, and 207, respectively, on a normalized basis. In particular, it should be noted that compositions 5F and 5G, containing small amounts of TKPP (0.06 and 0.03 wt%), resulted in very high removal rates of 205 and 207, respectively, on a normalized basis (compared to compositions 1D and 1F in Example 1, which contained 0.02 and 0.08 wt% TKPP). Compositions 5H and 5I showed that increasing the pH to 2.3 and 2.8 reduced surface undulation (to 132 and 125 on a normalized basis) without significantly decreasing the removal rate (normalized removal rates of 207 and 190).

[0058] Example 6 This example demonstrates that the aforementioned synergistic effect was observed when other quaternary amines (in addition to TEAH) were used in the polishing composition. As previously described in Example 5, each polishing composition contained 8.5% by weight of colloidal silica with an average particle size of 30 nm and sufficient nitric acid to adjust the pH to 1.8. Polishing compositions 1E and 1G were as previously described in Example 1. Compositions 6A, 6B, and 6C further contained TKPP in the amounts listed in Table 6 (all amounts are by weight percent). Compositions 6A and 6B contained alternative quaternary amines in the amounts listed (benzyltributylammonium chloride and tetrabutylammonium hydroxide). Composition 6C contained epsilon polylysine (a non-quaternary amine cationic compound).

[0059] Six glass disks (substrates) were polished using the Hamai 9B double-sided polishing tool under the polishing conditions described earlier in Example 1. The polishing speed and surface waviness HMS_Wq were also determined as described earlier in Example 1. The results for removal rate and surface waviness are shown in Table 6. These results were normalized to the removal rate and surface waviness achieved using polishing composition 1A, as reported in Table 1. TIFF2026076195000007.tif84170

[0060] As shown in Table 6, the synergistic effect previously observed in Example 5 was observed for other quaternary amines (in addition to TEAH). Compositions 6A and 6B achieved very high removal rates compared to composition 1G (similar to compositions 5B and 5C in Example 5) (normalized values ​​of 186 and 185). For composition 5C (non-quaternary ammonium compound), no synergistic effect was observed, and the removal rate was lower than that of composition 1E (normalized values ​​of 105:130), and similar surface undulation was observed.

[0061] References to ranges of values ​​are intended to serve as a convenient way to refer individually to each distinct value that falls within that range, unless otherwise indicated herein, and each distinct value is incorporated into the specification as if each value were referred to herein. All methods described herein may be performed in any suitable order, unless otherwise indicated herein, or unless it is clearly expressly inconsistent with the context. Any and all examples or exemplary language used herein (e.g., "such as") is intended merely to better illustrate the invention and does not limit the claims unless otherwise stated in the claims. No language in the specification should be considered to indicate that elements not described in the claims are essential for the practice of the invention.

[0062] Preferred embodiments of the present invention are disclosed herein, including the best modes known to the inventors for carrying out the invention. Modifications of these preferred embodiments may be apparent to those skilled in the art who have read the preceding description. The inventors anticipate that those skilled in the art will use such modifications as appropriate, and they intend that the invention may be carried out in ways other than those specified herein. Thus, the invention includes all modifications and equivalents of the subject matter referred to in the claims appended herein, as permitted by applicable law. Furthermore, any combination of the above elements in all possible modifications of the invention is incorporated herein unless otherwise indicated herein or is clearly inconsistent with the context.

Claims

1. A chemically mechanical abrasive composition, liquid carrier, Abrasive particles in liquid carrier, Pyrophosphate compounds, and Sulfonate compounds containing sulfonate anionic surfactants, or anionic polymers containing sulfonic acid groups. A chemically mechanical abrasive composition containing [a specific substance].

2. The composition according to claim 1, wherein the abrasive particles include colloidal silica particles.

3. The composition according to claim 1, wherein the abrasive particles have an average particle size in the range of about 15 nm to about 40 nm.

4. The composition according to claim 1, which contains approximately 5% to 15% by weight of abrasive particles when in use.

5. The composition according to claim 1, wherein the pyrophosphate compound comprises tetrapotassium pyrophosphate (TKPP) or tetrasodium pyrophosphate (TSPP).

6. When using, the pyrophosphate compound should be added in an amount of approximately 0.01% to approximately 0.2% by weight, When using, the sulfonate compound should be added in an amount of approximately 0.01% to approximately 0.2% by weight. The composition according to claim 1, comprising:

7. The composition according to claim 6, wherein the sulfonate compound comprises a disulfonate anionic surfactant.

8. The composition according to claim 7, wherein the sulfonate compound comprises an alkyldiphenyl oxide disulfonate anionic surfactant.

9. The composition according to claim 1, wherein the pH is in the range of approximately 1.5 to approximately 3.

10. The composition according to claim 1, further comprising an anionic polymer.

11. The composition according to claim 10, wherein the anionic polymer is a polyacrylate polymer or a polymethacrylate polymer.

12. A chemically mechanical abrasive composition, liquid carrier, Abrasive particles in liquid carrier, Pyrophosphate compounds, Compounds containing a quaternary ammonium group A chemically mechanical abrasive composition containing [a specific substance].

13. When using, the pyrophosphate compound should be added in an amount of approximately 0.01% to approximately 0.2% by weight, When using, the compound containing a quaternary ammonium group should be added in an amount of approximately 0.01% to approximately 0.2% by weight. The composition according to claim 12, comprising:

14. The composition according to claim 12, wherein the abrasive particles include colloidal silica particles.

15. The composition according to claim 14, wherein the abrasive particles have an average particle size in the range of about 15 nm to about 40 nm.

16. The composition according to claim 14, which contains approximately 5% to 15% by weight of abrasive particles when in use.

17. The composition according to claim 12, wherein the pyrophosphate compound comprises tetrapotassium pyrophosphate (TKPP) or tetrasodium pyrophosphate (TSPP).

18. The composition according to claim 12, wherein the compound containing a quaternary ammonium group comprises a tetramethylammonium group, a tetraethylammonium group, a tetrabutylammonium group, a benzyltributylammonium group, or a mixture thereof.

19. The composition according to claim 18, wherein the compound containing the quaternary ammonium group is tetraethylammonium hydroxide.

20. The composition according to claim 12, wherein the pH is in the range of about 1.5 to about 3.

21. A method for polishing a glass substrate, (a) bringing a glass substrate into contact with the polishing composition described in claim 12, (b) Moving the polishing composition and polishing pad with respect to the substrate, and (c) Polishing the surface of the substrate by polishing the substrate and removing a portion of the substrate, Methods that include...

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