Ceria-based slurry compositions for selective and non-selective CMP of silicon oxide, silicon nitride and polysilicon

Abstract

The present invention provides a chemical-mechanical polishing composition comprising: (a) ceria abrasive particles; (b) a cationic polymer; (c) a buffering agent; and (d) water, wherein the polishing composition has a pH of about 6 to about 9. The present invention also provides a method of chemically mechanically polishing substrates, particularly substrates comprising silicon oxide, silicon nitride, and polysilicon, using the polishing composition of the present invention.

Description

[Background technology]

[0001] 2. Background of the Invention In the manufacture of integrated circuits and other electronic devices, multiple layers of conductive, semiconductive, and dielectric materials are deposited on and removed from a substrate surface. As layers of material are sequentially deposited on and removed from the substrate, the top surface of the substrate may become non-planar and require planarization. Planarizing a surface, or "polishing" a surface, is the process of removing material from the surface of a substrate to form a substantially uniform, flat surface. Planarization is useful for removing undesirable surface topography and surface defects, such as rough surfaces, agglomerated materials, crystal lattice damage, scratches, and contaminated layers or materials. Planarization is also useful in forming features on a substrate by removing excess deposited material used to fill the features and providing a flat surface for subsequent levels of metallization and processing.

[0002] Compositions and methods for planarizing or polishing the surface of a substrate are well known in the art. Chemical mechanical planarization, or chemical mechanical polishing (CMP), is a common technique used to planarize substrates. CMP utilizes chemical compositions known as CMP compositions, or more simply polishing compositions (also called polishing slurries), to selectively remove material from a substrate. The polishing composition is typically applied to the substrate by contacting the surface of the substrate with a polishing pad (e.g., a polishing cloth or polishing disk) saturated with the polishing composition. Polishing of the substrate is typically further facilitated by the chemical activity of the polishing composition and / or the mechanical activity of an abrasive suspended in the polishing composition or incorporated in the polishing pad (e.g., a fixed abrasive polishing pad).

[0003] As the size of integrated circuits decreases and the number of integrated circuits on a chip increases, the components that make up the circuits must be placed closer together to fit into the limited space available on a typical chip. Effective isolation between circuits is important to ensure optimal semiconductor performance. To do so, shallow trenches are etched into a semiconductor substrate and filled with an insulating material to separate the active areas of the integrated circuits. More specifically, shallow trench isolation (STI) is a process in which a silicon nitride layer is formed on a silicon substrate, shallow trenches are formed by etching or photolithography, and a dielectric layer is deposited to fill the trenches. Because the depth of the trenches formed by this method varies, it is usually necessary to deposit an excess of dielectric material on top of the substrate to ensure complete filling of all trenches. The dielectric material (e.g., silicon oxide) conforms to the topography of the underlying layer of the substrate. Thus, the surface of the substrate is characterized by raised areas of the overlying oxide between the trenches, which is called a patterned oxide. The patterned oxide is characterized by the step height of the excess oxide dielectric material outside the trenches. The excess dielectric material is usually removed by a CMP process to provide a flatter surface for further processing. Once the patterned oxide has been polished to approach the flatness of the surface, the oxide layer is referred to as a blanket oxide.

[0004]

[0004] A polishing composition can be characterized according to its polishing rate (i.e., removal rate) and its planarization efficiency. Polishing rate refers to the rate of material removal from the surface of a substrate and is usually expressed in units of length (thickness) per unit time (e.g., angstroms (Å) per minute). Planarization efficiency relates to the reduction in step height relative to the amount of material removed from the substrate. Specifically, the polishing surface, e.g., a polishing pad, must first contact the "high points" of the surface and remove material to form a planar surface. Processes that achieve a planar surface with less material removal are considered to be more efficient than processes that require more material removal to achieve planarity.

[0005]

[0005] In many cases, the desired removal rates of silicon oxide, silicon nitride, and polysilicon may vary depending on the application. For example, in some cases, the silicon oxide pattern may be rate limiting for the dielectric polishing step in the STI process, so it is desirable to increase the removal rate of the silicon oxide pattern to increase device throughput. However, if the blanket removal rate is too fast, the oxide in the exposed trench will be over-polished, resulting in trench erosion and increased device defect rates. Therefore, in some cases (e.g., for polishing applications), it is desirable to have similar removal rates of silicon oxide, silicon nitride, and polysilicon, such as 1:1:1 selectivity.

[0006]

[0006] Although silicon oxide, silicon nitride, and polysilicon can be removed with approximately 1:1:1 selectivity, there remains a need for compositions and methods for chemical mechanical polishing that can be tailored to selectively remove silicon oxide, silicon nitride, and / or polysilicon compared to other dielectric materials.

[0007]

[0007] The present invention provides such a polishing composition and method. These and other advantages of the present invention, as well as additional inventive features, will become apparent from the description of the invention provided herein. Summary of the Invention

[0008] Summary of the Invention

[0008] The present invention provides a chemical mechanical polishing composition comprising: (a) ceria abrasive particles; (b) a cationic polymer; (c) a buffering agent; and (d) water, wherein the polishing composition has a pH of about 6 to about 9.

[0009]

[0009] The present invention further provides a method for chemically mechanically polishing a substrate, the method comprising: (i) providing a substrate; (ii) providing a polishing pad; (iii) providing a chemical mechanical polishing composition comprising: (a) ceria abrasive particles; (b) a cationic polymer; (c) a buffering agent; and (d) water, the polishing composition having a pH of about 6 to about 9; (iv) contacting the substrate with the polishing pad and the chemical mechanical polishing composition; and (v) moving the polishing pad and the chemical mechanical polishing composition relative to the substrate to abrade at least a portion of the substrate and polish the substrate. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Detailed Description of the Invention

[0010] The present invention provides a chemical mechanical polishing composition comprising, consisting essentially of, or consisting of: (a) ceria abrasive particles; (b) a cationic polymer; (c) a buffering agent; and (d) water, wherein the polishing composition has a pH of about 6 to about 9.

[0011]

[0011] The chemical mechanical polishing composition includes ceria abrasive particles. As used herein, the phrase "ceria abrasive particles" may be used interchangeably with "abrasive," "ceria particles," or "ceria abrasive." As is well known, ceria is an oxide of the rare earth metal cerium, also known as ceric oxide, cerium oxide (e.g., cerium(IV) oxide), or cerium dioxide. Cerium(IV) oxide (CeO2) can be formed by calcining cerium oxalate or cerium hydroxide. Cerium also forms cerium(III) oxide, e.g., Ce2O3. Ceria abrasive particles may include any one or more of these or other oxides of ceria.

[0012]

[0012] The ceria abrasive particles can be of any suitable type. In one embodiment, the ceria abrasive particles comprise, consist essentially of, or consist of calcined ceria particles, wet ceria particles, wet-processed ceria particles, or combinations thereof. In a preferred embodiment, the ceria abrasive particles comprise wet ceria particles or wet-processed ceria particles.

[0013] As used herein, "wet ceria particles" or "wet process based ceria particles" (collectively "wet process" ceria particles herein) refer to ceria prepared by precipitation, condensation polymerization, or similar processes (as opposed to, for example, fumed or pyrogenic ceria). It has been found that the polishing compositions of the present invention comprising wet process ceria particles exhibit lower defects when used to polish substrates according to the methods of the present invention. Without wishing to be bound by a particular theory, it is believed that wet process ceria comprises approximately spherical ceria particles and / or smaller agglomerated ceria particles, thereby resulting in lower substrate defectivity when used in the methods of the present invention. Exemplary wet process ceria are HC30™ and HC60™ ceria commercially available from Rhodia, and Hybrid-30 commercially available from ANP Co., Ltd.

[0014]

[0014] The ceria abrasive particles can have any suitable average particle size (i.e., average particle diameter). If the average particle size of the ceria abrasive particles is too small, the polishing composition may not exhibit a sufficient removal rate. In contrast, if the average particle size of the ceria abrasive particles is too large, the polishing composition may exhibit undesirable polishing performance, such as poor substrate defectivity. Thus, the ceria abrasive particles can have an average particle size of about 10 nm or more, such as about 15 nm or more, about 20 nm or more, about 25 nm or more, about 30 nm or more, about 35 nm or more, about 40 nm or more, about 45 nm or more, or about 50 nm or more. Alternatively or additionally, the ceria abrasive particles can have an average particle size of about 1,000 nm or less, such as about 750 nm or less, about 500 nm or less, about 250 nm or less, about 150 nm or less, about 100 nm or less, about 75 nm or less, or about 50 nm or less. Thus, the ceria abrasive particles can have an average particle size limited by any two of the aforementioned endpoints. For example, the ceria abrasive particles can have an average particle size of about 10 nm to about 1,000 nm, such as about 10 nm to about 750 nm, about 15 nm to about 500 nm, about 20 nm to about 250 nm, about 20 nm to about 150 nm, about 25 nm to about 150 nm, about 25 nm to about 100 nm, about 50 nm to about 150 nm, or about 50 nm to about 100 nm. In the case of spherical ceria abrasive particles, the size of a particle is the diameter of the particle. In the case of non-spherical ceria abrasive particles, the size of a particle is the diameter of the smallest sphere that encompasses the particle. The particle size of the ceria abrasive particles can be measured using any suitable technique, for example, using laser diffraction techniques. Suitable particle size measuring instruments are available, for example, from Malvern Instruments (Malvern, UK).

[0015] In some embodiments, the ceria abrasive particles of the polishing composition exhibit a multimodal particle size distribution. As used herein, the term "multimodal" means that the ceria abrasive particles exhibit an average particle size distribution having at least two maxima (e.g., two or more maxima, three or more maxima, four or more maxima, or five or more maxima). Preferably, in these embodiments, the ceria abrasive particles exhibit a bimodal particle size distribution, i.e., the ceria abrasive particles exhibit a particle size distribution having two average particle size maxima. The terms "maximum and maxima" refer to one or more peaks in the particle size distribution. The one or more peaks correspond to the average particle sizes of the ceria abrasive particles described herein. Thus, for example, a plot of number of particles versus particle size will reflect a bimodal particle size distribution with a first peak in the particle size range of about 75 nm to about 150 nm, e.g., about 80 nm to about 140 nm, about 85 nm to about 130 nm, or about 90 nm to about 120 nm, and a second peak in the particle size range of about 25 nm to about 70 nm, e.g., about 30 nm to about 65 nm, about 35 nm to about 65 nm, or about 40 nm to about 60 nm. Ceria abrasive particles having a multimodal particle size distribution can be obtained by combining two different ceria abrasive particles, each having a unimodal particle size distribution.

[0016]

[0016] The ceria abrasive particles are preferably colloidally stable in the polishing compositions of the present invention. The term colloid refers to a suspension of ceria abrasive particles in an aqueous carrier (e.g., water). Colloidal stability refers to the maintenance of that suspension over time. In the context of the present invention, an abrasive is considered colloidally stable if, when the abrasive is placed in a 100 mL graduated cylinder and allowed to stand unstirred for 2 hours, the difference between the concentration of the particles in the bottom 50 mL of the graduated cylinder ([B] (in g / mL)) and the concentration of the particles in the top 50 mL of the graduated cylinder ([T] (in g / mL)), divided by the initial concentration of the particles in the abrasive composition, is 0.5 or less (i.e., {[B]-[T]} / [C]≦0.5). More preferably, the value of [B]-[T] / [C] is 0.3 or less, and most preferably 0.1 or less.

[0017]

[0017] The polishing composition can include any suitable concentration of ceria abrasive particles. If the polishing composition of the present invention includes too few ceria abrasive particles, the composition may not exhibit sufficient removal rate. In contrast, if the polishing composition includes too many ceria abrasive particles, the polishing composition may exhibit undesirable polishing performance and / or may not be cost-effective and / or may lack stability. The polishing composition includes about 10% by weight or less of ceria abrasive particles, for example, about 9% by weight or less, about 8% by weight or less, about 7% by weight or less, about 6% by weight or less, about 5% by weight or less, about 4% by weight or less, about 3% by weight or less, about 2% by weight or less, about 1% by weight or less, about 0.9% by weight or less, about 0.8% by weight or less, about 0.7% by weight or less, about 0.6% by weight or less, or about 0.5% by weight or less. Alternatively or additionally, the polishing composition may comprise about 0.001% by weight or more of ceria abrasive particles, e.g., about 0.005% by weight or more, about 0.01% by weight or more, about 0.05% by weight or more, or about 0.1% by weight or more of ceria abrasive particles. Thus, the ceria abrasive particles may be present in the polishing composition at a concentration bounded by any two of the foregoing endpoints. For example, the polishing composition may comprise about 0.001% by weight to about 10% by weight of ceria abrasive particles, e.g., about 0.001% by weight to about 9% by weight, about 0.005% by weight to about 8% by weight, about 0.01% by weight to about 7% by weight, about 0.05% by weight to about 6% by weight, about 0.1% by weight to about 5% by weight, about 0.5% by weight to about 5% by weight, about 0.5% by weight to about 4% by weight, about 1% by weight to about 3% by weight, or about 1.5% by weight to about 2.5% by weight of ceria abrasive particles. In one embodiment, the polishing composition can include from about 0.1% to about 1%, or from about 0.1% to about 0.5% by weight of ceria abrasive particles at the point of use. In another embodiment, the polishing composition can include from about 1% to about 3% (e.g., about 1.2% or about 1.6%) by weight of ceria abrasive particles as a concentrate.

[0018] The chemical mechanical polishing composition includes a cationic polymer. The cationic polymer can include any suitable cationic monomer capable of undergoing free radical polymerization and / or addition polymerization. In some embodiments, the cationic polymer can be N-vinylimidazole, 2-(dimethylamino)ethyl acrylate ("DMAEA"), 2-(dimethylamino)ethyl methacrylate ("DMAEM"), 3-(dimethylamino)propyl methacrylamide ("DMAPMA"), 3-(dimethylamino)propyl acrylamide ("DMAPA"), 3-methacrylamidopropyl-trimethyl-ammonium chloride ("MAPTAC"), 3-acrylamidopropyl-trimethyl-ammonium chloride ("APTAC"), diallyl diethyl acrylate ("DMPA"), 3-(dimethylamino)propyl methacrylate ("DMAEM"), 3-(dimethylamino)propyl methacryl ...PMA"), 3-(dimethylamino)propyl acrylamide ("DMAPA"), 3-(dimethylamino)propyl methacrylamide ("DMAPMA"), 3-(dimethylamino)propyl acrylamide ("DMAPA"), 3-(dimethylamino)propyl methacrylamide ("DMAPMA"), 3-(dimethylamino)propyl methacrylamide ("DMAPMA"), 3-(dimethylamino)propyl methacrylamide ("DMAPMA"), 3-(dimethylamino)propyl methacrylamide ("DMAPMA"), 3-(dimethylamino)propyl methacrylamide ("DMAPMA"), 3-(dimethylamino)propyl methacrylamide ("DMAPMA"), 3-(dimethylamino)propyl methacrylamide (" Cationic monomers selected from N-vinylimidazole, diallyldimethylammonium chloride ("DADMAC"), 2-(acryloyloxy)-N,N,N-trimethylethanaminium chloride ("DMAEA.MCQ"), 2-(methacryloyloxy)-N,N,N-trimethylethanaminium chloride ("DMAEM.MCQ"), N,N-dimethylaminoethyl acrylate benzyl chloride ("DMAEA.BCQ"), N,N-dimethylaminoethyl methacrylate benzyl chloride ("DMAEM.BCQ"), salts thereof, and combinations thereof. Certain embodiments include cationic monomers selected from N-vinylimidazole, diallyldimethylammonium chloride ("DADMAC"), 2-(methacryloyloxy)-N,N,N-trimethylethanaminium chloride ("DMAEM.MCQ"), salts thereof, and combinations thereof. In other words, the cationic polymer can be polyvinylimidazole, polyDADMAC, polyMADQUAT (e.g., polyDMAEM.MCQ), a salt thereof, or a combination thereof. In a preferred embodiment, the polishing composition comprises polyMADQUAT and, optionally, an additional cationic polymer selected from polyvinylimidazole and polyDADMAC.

[0019]

[0019] The polishing composition can include any suitable amount of cationic polymer. The polishing composition can include about 10 ppm or more of cationic polymer, for example, about 15 ppm or more, about 20 ppm or more, about 25 ppm or more, about 30 ppm or more, about 35 ppm or more, or about 40 ppm or more of cationic polymer. Alternatively or in addition, the polishing composition can include about 1000 ppm or less of cationic polymer, for example, about 800 ppm or less, about 600 ppm or less, about 400 ppm or less, about 200 ppm or less, or about 100 ppm or less of cationic polymer. Thus, the polishing composition can include cationic polymer in an amount limited by any two of the aforementioned endpoints. For example, the polishing composition may contain about 10 ppm to about 1000 ppm of cationic polymer, e.g., about 10 ppm to about 800 ppm, about 10 ppm to about 600 ppm, about 10 ppm to about 400 ppm, about 10 ppm to about 200 ppm, about 10 ppm to about 100 ppm, about 25 ppm to about 1000 ppm, about 25 ppm to about 800 ppm, about 25 ppm to about 600 ppm, about 25 ppm to about 400 ppm, about 25 ppm to about 200 ppm, or about 25 ppm to about 100 ppm of cationic polymer.

[0020] The cationic polymer can be present as any suitable structural type. For example, the cationic polymer can be present as an alternating polymer, a random polymer, a block polymer, a graft polymer, a linear polymer, a branched polymer, or a combination thereof. The cationic polymer can include a single monomer unit, or any suitable number of different monomer units. For example, the cationic polymer can include two different monomer units, three different monomer units, four different monomer units, five different monomer units, or six different monomer units. The cationic monomers of the cationic polymer can be present in any suitable concentration and in any suitable ratio. In some embodiments, the cationic polymer further includes a monomer selected from methacrylamide, acrylamide, and combinations thereof.

[0021] The cationic polymer can have any suitable weight average molecular weight. The cationic polymer can have a weight average molecular weight of about 150 g / mol or more, for example, about 300 g / mol or more, about 500 g / mol or more, about 600 g / mol or more, about 750 g / mol or more, about 1000 g / mol or more, about 1500 g / mol or more, about 2000 g / mol or more, about 2500 g / mol or more, about 3000 g / mol or more, about 3500 g / mol or more, about 4000 g / mol or more, about 4500 g / mol or more, about 5000 g / mol or more, about 5500 g / mol or more, about 6000 g / mol or more, about 6500 g / mol or more, about 7000 g / mol or more, or about 7500 g / mol or more. Alternatively or additionally, the cationic polymer can have a weight average molecular weight of about 10,000 g / mol or less, e.g., about 9,000 g / mol or less, about 8,000 g / mol or less, about 7,500 g / mol or less, about 7,000 g / mol or less, about 6,500 g / mol or less, about 6,000 g / mol or less, about 5,500 g / mol or less, about 5,000 g / mol or less, about 4,500 g / mol or less, about 4,000 g / mol or less, about 3,500 g / mol or less, about 3,000 g / mol or less, about 2,500 g / mol or less, or about 2,000 g / mol or less. Thus, the cationic polymer can have a weight average molecular weight bounded by any two of the aforementioned endpoints. For example, the cationic polymer has a weight average molecular weight of about 150 g / mol to about 10,000 g / mol, for example, about 300 g / mol to about 9,000 g / mol, about 500 g / mol to about 8,000 g / mol, about 150 g / mol to about 7,000 g / mol, about 150 g / mol to about 6,000 g / mol, about 150 g / mol to about 5,000 g / mol, about 150 g / mol to about 5,000 g / mol, about 150 g / mol to about 6,000 g / mol, about 150 g / mol to about 7,000 g / mol, about 150 g / mol to about 8,000 g / mol, about 150 g / mol to about 9,000 g / mol, about 150 g / mol to about 9,000 g The polymer may have a weight average molecular weight of about 2000 g / mol, about 1000 g / mol to about 10,000 g / mol, about 1000 g / mol to about 9000 g / mol, about 1000 g / mol to about 8000 g / mol, about 1000 g / mol to about 7000 g / mol, about 1000 g / mol to about 6000 g / mol, or about 1000 g / mol to about 5000 g / mol.

[0022]

[0022] The chemical-mechanical polishing composition includes a buffering agent. The buffering agent can be any suitable compound or combination of compounds capable of maintaining the pH of the polishing composition at about 3 to about 9 (e.g., a pH of about 6 to about 9). Typically, the buffering agent is an amine-based compound containing 1 to 5 nitrogen atoms. For example, the buffering agent can be a heterocyclic or heteroaromatic amine-based compound containing 1 to 5 nitrogen atoms. In some embodiments, the buffer comprises a heterocyclic or heteroaromatic amine selected from pyrrole, pyrrolidine, carbazole, isoindole, indole, pyrroline, indolizine, indoline, pyridine, piperidine, quinolizine, isoquinoline, quinoline, naphthyridine, imidazole, imidazoline, imidazolidine, tetrazole, triazole, benimidazole, purine, benzoxazole, benzthiazole, isothiazole, isoxazole, thiazole, oxazole, morpholine, thiomorpholine, pyrazole, pyrazoline, pteridine, triazine, pyrimidine, pyrazine, piperazine, indazole, pyridazine, and combinations thereof. In certain embodiments, the buffer is benzotriazole, 5-aminotetrazole, or a combination thereof.

[0023]

[0023] The polishing composition can include any suitable amount of buffering agent. The polishing composition can include about 25 ppm or more of buffering agent, e.g., about 50 ppm or more, about 100 ppm or more, or about 200 ppm or more of buffering agent. Alternatively or in addition, the polishing composition can include about 5000 ppm or less of buffering agent, e.g., about 4000 ppm or less, about 3000 ppm or less, about 2000 ppm or less, or about 1000 ppm or less of buffering agent. Thus, the polishing composition can include a buffering agent in an amount limited by any two of the foregoing endpoints. For example, the polishing composition may contain about 25 ppm to about 5000 ppm of the buffering agent, e.g., about 25 ppm to about 400 ppm, about 25 ppm to about 3000 ppm, about 25 ppm to about 2000 ppm, about 25 ppm to about 1000 ppm, about 50 ppm to about 5000 ppm, about 50 ppm to about 4000 ppm, about 50 ppm to about 3000 ppm, about 50 ppm to about 2000 ppm, about 50 ppm to about 1000 ppm, about 100 ppm to about 5000 ppm, or about 100 ppm to about 1000 ppm of the buffering agent.

[0024]

[0024] In some embodiments, the polishing composition further comprises a non-ionic polymer. Thus, in some aspects, the invention provides a chemical-mechanical polishing composition comprising, consisting essentially of, or consisting of: (a) ceria abrasive particles; (b) a cationic polymer; (c) a buffering agent; (d) a non-ionic polymer; and (e) water, wherein the polishing composition has a pH of about 6 to about 9.

[0025] The nonionic polymer can be any suitable polymer that does not have a cationic or anionic charge at a pH of about 6 to about 9 (e.g., a pH of about 7 to about 9). In some embodiments, the nonionic polymer is selected from polyalkylene glycols, polyetheramines, polyethylene oxide / polypropylene oxide copolymers, polyacrylamides, polyvinylpyrrolidones, siloxane polyalkylene oxide copolymers, hydrophobically modified polyacrylate copolymers, hydrophilic nonionic polymers, polysaccharides, and combinations thereof. In certain embodiments, the nonionic polymer is polyvinylpyrrolidone, polyalkylene glycols (e.g., polyethylene glycol (PEG) or polypropylene oxide (PPO)), polyethylene oxide / polypropylene oxide copolymers, or combinations thereof. In a preferred embodiment, the nonionic polymer is polyethylene glycol (PEG).

[0026]

[0026] The nonionic polymer can have any suitable weight average molecular weight. The nonionic polymer can have a weight average molecular weight of about 400 g / mol or more, for example, about 500 g / mol or more, about 600 g / mol or more, about 750 g / mol or more, about 1000 g / mol or more, about 1500 g / mol or more, about 2000 g / mol or more, about 2500 g / mol or more, about 3000 g / mol or more, about 3500 g / mol or more, about 4000 g / mol or more, about 4500 g / mol or more, about 5000 g / mol or more, about 5500 g / mol or more, about 6000 g / mol or more, about 6500 g / mol or more, about 7000 g / mol or more, or about 7500 g / mol or more. Alternatively or additionally, the nonionic polymer can have a weight average molecular weight of about 10,000 g / mol or less, e.g., about 9,000 g / mol or less, about 8,000 g / mol or less, about 7,500 g / mol or less, about 7,000 g / mol or less, about 6,500 g / mol or less, about 6,000 g / mol or less, about 5,500 g / mol or less, about 5,000 g / mol or less, about 4,500 g / mol or less, about 4,000 g / mol or less, about 3,500 g / mol or less, about 3,000 g / mol or less, about 2,500 g / mol or less, or about 2,000 g / mol or less. Thus, the nonionic polymer can have a weight average molecular weight bounded by any two of the aforementioned endpoints. For example, the nonionic polymer may have a weight average molecular weight of about 400 g / mol to about 10,000 g / mol, e.g., about 400 g / mol to about 9,000 g / mol, about 400 g / mol to about 8,000 g / mol, about 400 g / mol to about 7,000 g / mol, about 400 g / mol to about 6,000 g / mol, about 400 g / mol to about 5,000 g / mol, about 1,000 g / mol to about 10,000 g / mol, about 1,000 g / mol to about 9,000 g / mol, about 1,000 g / mol to about 8,000 g / mol, about 1,000 g / mol to about 7,000 g / mol, about 1,000 g / mol to about 6,000 g / mol, or about 1,000 g / mol to about 5,000 g / mol.

[0027]

[0027] When present, the polishing composition can include any suitable amount of nonionic polymer. The polishing composition can include about 25 ppm or more of nonionic polymer, e.g., about 50 ppm or more, about 100 ppm or more, or about 200 ppm or more of nonionic polymer. Alternatively or in addition, the polishing composition can include about 5000 ppm or less of nonionic polymer, e.g., about 4000 ppm or less, about 3000 ppm or less, about 2000 ppm or less, or about 1000 ppm or less of nonionic polymer. Thus, the polishing composition can include nonionic polymer in an amount limited by any two of the foregoing endpoints. For example, the polishing composition may contain about 25 ppm to about 5000 ppm of nonionic polymer, e.g., about 25 ppm to about 400 ppm, about 25 ppm to about 3000 ppm, about 25 ppm to about 2000 ppm, about 25 ppm to about 1000 ppm, about 50 ppm to about 5000 ppm, about 50 ppm to about 4000 ppm, about 50 ppm to about 3000 ppm, about 50 ppm to about 2000 ppm, about 50 ppm to about 1000 ppm, about 100 ppm to about 5000 ppm, or about 100 ppm to about 1000 ppm of nonionic polymer.

[0028]

[0028] In some embodiments, the polishing composition further comprises a cationic surfactant. Thus, in some aspects, the invention provides a chemical-mechanical polishing composition comprising, consisting essentially of, or consisting of: (a) ceria abrasive particles; (b) a cationic polymer; (c) a buffering agent; (d) a cationic surfactant; and (e) water, wherein the polishing composition has a pH of about 6 to about 9.

[0029] The cationic surfactant may be any suitable surfactant that carries a cationic charge at neutral pH (i.e., a pH of about 7). Generally, the cationic surfactant comprises a quaternary ammonium salt. For example, the cationic surfactant may be an alkylammonium salt, such as an alkylammonium p-toluenesulfonate or an alkylammonium chloride. In certain embodiments, the cationic surfactant is selected from N,N,N',N',N'-pentamethyl-N-tallow alkyl-1,3-propanediammonium dichloride, (oxydi-2,1-ethanediyl)bis(cocoalkyl)dimethylammonium dichloride, salts thereof, and combinations thereof.

[0030]

[0030] The polishing composition, when present, can include any suitable amount of cationic surfactant. The polishing composition can include about 10 ppm or more of cationic polymer, such as about 15 ppm or more, about 20 ppm or more, about 25 ppm or more, about 30 ppm or more, about 35 ppm or more, or about 40 ppm or more of cationic surfactant. Alternatively or in addition, the polishing composition can include about 1000 ppm or less of cationic surfactant, such as about 800 ppm or less, about 600 ppm or less, about 400 ppm or less, about 200 ppm or less, or about 100 ppm or less of cationic surfactant. Thus, the polishing composition can include cationic surfactant in an amount limited by any two of the aforementioned endpoints. For example, the polishing composition may contain about 10 ppm to about 1000 ppm of cationic surfactant, e.g., about 10 ppm to about 800 ppm, about 10 ppm to about 600 ppm, about 10 ppm to about 400 ppm, about 10 ppm to about 200 ppm, about 10 ppm to about 100 ppm, about 25 ppm to about 1000 ppm, about 25 ppm to about 800 ppm, about 25 ppm to about 600 ppm, about 25 ppm to about 400 ppm, about 25 ppm to about 200 ppm, or about 25 ppm to about 100 ppm of cationic surfactant.

[0031] In some embodiments, the polishing composition further comprises a self-terminating agent. Thus, in some aspects, the invention provides a chemical-mechanical polishing composition comprising, consisting essentially of, or consisting of: (a) ceria abrasive particles; (b) a cationic polymer; (c) a buffering agent; (d) a self-terminating agent; and (e) water, wherein the polishing composition has a pH of about 6 to about 9.

[0032]

[0032] The self-terminating agent may be any suitable compound capable of reducing the removal rate of one or more of silicon oxide, silicon nitride, and polysilicon. In some embodiments, the self-terminating agent has the formula (I): TIFF2025505182000001.tif27170, where R is selected from hydrogen, alkyl, heteroalkyl, cycloalkyl, heterocycloalkyl, aryl, and heteroaryl, each of which may be substituted or unsubstituted.

[0033] As used herein, the term "alkyl" refers to a straight or branched chain, saturated or unsaturated, aliphatic group having the indicated number of carbon atoms. Alkyl can be any number of carbons, e.g., C 1-2 , C 1-3 , C 1-4 , C 1-5 , C 1-6 , C 1-7 , C 1-8 , C 1-9 , C 1-10 , C 2-3 , C 2-4 , C 2-5 , C 2-6 , C 3-4 , C 3-5 , C 3-6 , C 4-5 , C 4-6 and C 5-6 For example, C 1-6Alkyl includes, but is not limited to, methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl, tert-butyl, pentyl, isopentyl, hexyl, and the like. Alkyl can also refer to alkyl groups having up to 30 carbon atoms, such as, but not limited to, heptyl, octyl, nonyl, decyl, and the like. Alkyl groups can be substituted or unsubstituted. A "substituted alkyl" group can be substituted with one or more groups selected from halo, hydroxy, amino, oxo (=O), alkylamino, amido, acyl, nitro, cyano, and alkoxy.

[0034]

[0034] As used herein, the term "heteroalkyl" refers to an alkyl group, as described herein, in which one or more carbon atoms are optionally replaced with a heteroatom, independently selected from N, O, and S.

[0035] As used herein, the term "cycloalkyl" refers to a saturated or partially unsaturated monocyclic, fused bicyclic, or bridged polycyclic ring assembly containing 3 to 12 ring atoms, or the indicated number of atoms. Cycloalkyl groups may include any number of carbons, e.g., C 3-6 , C 4-6 , C 5-6 , C 3-8 , C 4-8 , C 5-8 , C 6-8 , C 3-9 , C 3-10 , C 3-11 , and C 3-12Saturated monocyclic carbocycles include, for example, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, and cyclooctyl. Saturated bicyclic and polycyclic carbocycles include, for example, norbornane, [2.2.2]bicyclooctane, decahydronaphthalene, and adamantane. Carbocyclic groups can also be partially unsaturated, having one or more double or triple bonds in the ring. Representative partially unsaturated carbocyclic groups include, but are not limited to, cyclobutene, cyclopentene, cyclohexene, cyclohexadiene (1,3- and 1,4-isomers), cycloheptene, cycloheptadiene, cyclooctene, cyclooctadiene (1,3-, 1,4-, and 1,5-isomers), norbornene, and norbornadiene.

[0036]

[0036] As used herein, the term "heterocycloalkyl" refers to a cycloalkyl group, as described herein, in which one or more carbon atoms are optionally replaced with a heteroatom independently selected from N, O, and S.

[0037]

[0037] As used herein, the term "aryl" refers to an aromatic ring system having any suitable number of ring atoms and any suitable number of rings. An aryl group can contain any suitable number of ring atoms, for example, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, or 16 ring atoms, and 6-10, 6-12, or 6-14 ring members. Aryl groups can be monocyclic, fused to form bicyclic or tricyclic groups, or linked by bonds to form biaryl groups. Representative aryl groups include phenyl, naphthyl, and biphenyl. Other aryl groups include benzyl with methylene linking groups. Some aryl groups have 6-12 ring members, such as phenyl, naphthyl, or biphenyl. Other aryl groups have 6-10 ring members, such as phenyl or naphthyl.

[0038]

[0038] As used herein, the term "heteroaryl" refers to an aryl group as described herein, wherein one or more carbon atoms are optionally replaced with a heteroatom independently selected from N, O, and S.

[0039] In certain embodiments, the self-terminating agent is selected from hydroxamic acid, acetohydroxamic acid, benzhydroxamic acid, salicylhydroxamic acid, and combinations thereof.

[0040]

[0040] The polishing composition, when present, can include any suitable amount of the self-cutter. The polishing composition can include about 10 ppm or more of the self-cutter, e.g., about 15 ppm or more, about 20 ppm or more, about 25 ppm or more, about 30 ppm or more, about 35 ppm or more, or about 40 ppm or more of the self-cutter. Alternatively or in addition, the polishing composition can include about 1000 ppm or less of the self-cutter, e.g., about 800 ppm or less, about 600 ppm or less, about 400 ppm or less, about 200 ppm or less, or about 100 ppm or less of the self-cutter. Thus, the polishing composition can include the self-cutter in an amount limited by any two of the foregoing endpoints. For example, the polishing composition can contain from about 10 ppm to about 1000 ppm of the self-canceling agent, e.g., from about 10 ppm to about 800 ppm, from about 10 ppm to about 600 ppm, from about 10 ppm to about 400 ppm, from about 10 ppm to about 200 ppm, from about 10 ppm to about 100 ppm, from about 25 ppm to about 1000 ppm, from about 25 ppm to about 800 ppm, from about 25 ppm to about 600 ppm, from about 25 ppm to about 400 ppm, from about 25 ppm to about 200 ppm, or from about 25 ppm to about 100 ppm of the self-canceling agent.

[0041]

[0041] The chemical mechanical polishing composition may include one or more compounds (i.e., pH adjusting compounds) capable of adjusting (i.e., adjusting) the electrical conductivity of the polishing composition. The electrical conductivity of the polishing composition may be adjusted using any suitable electrical conductivity adjuster described herein. Typically, the chemical mechanical polishing composition has an electrical conductivity of at least 170 μS / cm (e.g., at least 200 μS / cm, at least 250 μS / cm, at least 300 μS / cm, at least 350 μS / cm, at least 400 μS / cm, at least 450 μS / cm, or at least 500 μS / cm) at the point of use. For example, the chemical mechanical polishing composition may have an electrical conductivity of 170 μS / cm to 2000 μS / cm, 350 μS / cm to 2000 μS / cm, or 500 μS / cm to 2000 μS / cm. Preferably, the chemical mechanical polishing composition has a conductivity at the point of use of between 350 μS / cm and 2000 μS / cm.

[0042]

[0042] Thus, in some embodiments, the polishing composition further comprises a conductivity modifier. Thus, in some aspects, the invention provides a chemical-mechanical polishing composition comprising, consisting essentially of, or consisting of: (a) ceria abrasive particles; (b) a cationic polymer; (c) a buffering agent; (d) a conductivity modifier; and (e) water, wherein the polishing composition has a pH of about 6 to about 9.

[0043]

[0043] As used herein, the term "conductivity adjust" refers to any small molecule salt capable of adjusting the conductivity of the polishing composition. In some embodiments, the conductivity adjuster is selected from ammonium salts, potassium salts, and combinations thereof. The conductivity adjuster can have any suitable counterion. For example, the conductivity adjuster can have a counterion selected from nitrates, acetates, halides, phosphates, and sulfates. Thus, in some embodiments, the conductivity adjuster is selected from ammonium nitrate, ammonium acetate, ammonium halides, ammonium phosphates, ammonium sulfate, potassium nitrate, potassium acetate, potassium halides, potassium phosphates, potassium sulfate, or combinations thereof.

[0044] In some embodiments, the conductivity adjuster is selected from ammonium nitrate, ammonium chloride, ammonium bromide, ammonium acetate, potassium nitrate, potassium chloride, potassium bromide, potassium acetate, diallyldimethylammonium chloride, tetrabutylammonium bromide, tetramethylammonium bromide, tetraethylammonium bromide, benzyltrimethylammonium bromide, tetrabutylammonium chloride, tetramethylammonium chloride, tetraethylammonium chloride, benzyltrimethylammonium chloride, tetrabutylammonium acetate, tetramethylammonium acetate, tetraethylammonium acetate, benzyltrimethylammonium acetate, and combinations thereof. In one embodiment, the conductivity adjuster is selected from diallyldimethylammonium chloride, tetrabutylammonium bromide, tetramethylammonium bromide, tetraethylammonium bromide, benzyltrimethylammonium bromide, tetrabutylammonium chloride, tetramethylammonium chloride, tetraethylammonium chloride, benzyltrimethylammonium chloride, tetrabutylammonium acetate, tetramethylammonium acetate, tetraethylammonium acetate, benzyltrimethylammonium acetate, and combinations thereof. In another embodiment, the conductivity adjuster is selected from ammonium nitrate, ammonium chloride, ammonium bromide, ammonium acetate, potassium nitrate, potassium chloride, potassium bromide, potassium acetate, and combinations thereof. In a particular embodiment, the conductivity adjuster is selected from ammonium nitrate, potassium nitrate, diallyldimethylammonium chloride, tetrabutylammonium bromide, tetramethylammonium bromide, and combinations thereof.

[0045]

[0045] The polishing composition, when present, can include any suitable amount of the conductivity modifier. The polishing composition can include about 25 ppm or more of the conductivity modifier, e.g., about 50 ppm or more, about 100 ppm or more, or about 200 ppm or more. Alternatively or in addition, the polishing composition can include about 5000 ppm or less of the conductivity modifier, e.g., about 4000 ppm or less, about 3000 ppm or less, about 2000 ppm or less, or about 1000 ppm or less. Thus, the polishing composition can include the conductivity modifier in an amount limited by any two of the foregoing endpoints. For example, the polishing composition may contain about 25 ppm to about 5000 ppm of the conductivity adjuster, e.g., about 25 ppm to about 400 ppm, about 25 ppm to about 3000 ppm, about 25 ppm to about 2000 ppm, about 25 ppm to about 1000 ppm, about 50 ppm to about 5000 ppm, about 50 ppm to about 4000 ppm, about 50 ppm to about 3000 ppm, about 50 ppm to about 2000 ppm, about 50 ppm to about 1000 ppm, about 100 ppm to about 5000 ppm, or about 100 ppm to about 1000 ppm of the conductivity adjuster.

[0046]

[0046] In some aspects, the present invention provides a chemical mechanical polishing composition comprising, consisting essentially of, or consisting of: (a) ceria abrasive particles; (b) cationic polymer; (c) buffer; (d) nonionic polymer; (e) cationic surfactant; and (f) water, wherein the polishing composition has a pH of about 6 to about 9.

[0047]

[0047] In some aspects, the present invention provides a chemical-mechanical polishing composition comprising, consisting essentially of, or consisting of: (a) ceria abrasive particles; (b) cationic polymer; (c) buffer; (d) cationic surfactant; (e) self-terminating agent; and (f) water, wherein the polishing composition has a pH of about 6 to about 9.

[0048]

[0048] In some aspects, the present invention provides a chemical mechanical polishing composition comprising, consisting essentially of, or consisting of: (a) ceria abrasive particles; (b) cationic polymer; (c) buffer; (d) conductivity modifier; (e) cationic surfactant; and (f) water, wherein the polishing composition has a pH of about 6 to about 9.

[0049]

[0049] In some aspects, the present invention provides a chemical mechanical polishing composition comprising, consisting essentially of, or consisting of: (a) ceria abrasive particles; (b) cationic polymer; (c) buffer; (d) conductivity modifier; (e) nonionic polymer; and (f) water, wherein the polishing composition has a pH of about 6 to about 9.

[0050]

[0050] The polishing composition includes an aqueous carrier. The aqueous carrier includes water (e.g., deionized water) and may contain one or more water-miscible organic solvents. Examples of organic solvents that can be used include alcohols such as propenyl alcohol, isopropyl alcohol, ethanol, 1-propanol, methanol, and 1-hexanol; aldehydes such as acetylaldehyde; ketones such as acetone, diacetone alcohol, and methyl ethyl ketone; esters such as ethyl formate, propyl formate, ethyl acetate, methyl acetate, methyl lactate, butyl lactate, and ethyl lactate; ethers including sulfoxides such as dimethyl sulfoxide (DMSO), tetrahydrofuran, dioxane, and diglyme; amides such as N,N-dimethylformamide, dimethylimidazolidinone, and N-methylpyrrolidone; polyhydric alcohols and derivatives thereof such as ethylene glycol, glycerol, diethylene glycol, and diethylene glycol monomethyl ether; and nitrogen-containing organic compounds such as acetonitrile, amylamine, isopropylamine, imidazole, and dimethylamine. Preferably, the aqueous carrier is water only, ie, there is no organic solvent present.

[0051]

[0051] The chemical-mechanical polishing composition may include one or more compounds capable of adjusting (i.e., adjusting) the pH of the polishing composition (i.e., pH adjusting compounds). The pH of the polishing composition may be adjusted using any suitable compound capable of adjusting the pH of the polishing composition. The pH adjusting compound is desirably water-soluble and compatible with the other components of the polishing composition. Typically, the chemical-mechanical polishing composition has a pH of about 6 to about 9 at the point of use (e.g., a pH of about 6 to about 8, about 6 to about 7, about 7 to about 9, about 8 to about 9, about 6.5 to about 8.5, about 6.5 to about 7.5, or about 7.5 to about 8.5). Preferably, the chemical-mechanical polishing composition has a pH of about 6 to about 9 or about 7 to about 8 at the point of use.

[0052] The compound capable of adjusting the pH may be selected from the group consisting of ammonium salts, alkali metal salts, carboxylic acids, alkali metal hydroxides, alkali metal carbonates, alkali metal bicarbonates, borates, and mixtures thereof.

[0053]

[0053] The chemical-mechanical polishing composition optionally further comprises one or more additives. Exemplary additives include conditioners, acids (e.g., sulfonic acids), complexing agents, chelating agents, biocides, scale inhibitors, and dispersants.

[0054]

[0054] When present, the biocide may be any suitable biocide and may be present in the polishing composition in any suitable amount. A suitable biocide is an isothiazolinone biocide. The biocide may be present in the polishing composition at a concentration of about 1 to about 750 ppm, preferably about 20 to about 200 ppm.

[0055]

[0055] The polishing composition can be manufactured by any suitable technique, many of which are known to those skilled in the art. The polishing composition can be prepared in a batch or continuous process. Generally, the polishing composition is prepared by combining the components of the polishing composition. As used herein, the term "component" includes individual components (e.g., ceria abrasive particles, cationic polymer, buffering agent, optional conductivity modifier, optional cationic surfactant, optional non-ionic polymer, optional self-stopping agent, and / or other optional additives) as well as any combination of components (e.g., ceria abrasive particles, cationic polymer, buffering agent, optional conductivity modifier, optional cationic surfactant, optional non-ionic polymer, optional self-stopping agent, and / or other optional additives, etc.).

[0056]

[0056] For example, the polishing composition can be prepared by (i) providing all or a portion of a liquid carrier; (ii) dispersing the ceria abrasive particles, the cationic polymer, the buffer, the optional conductivity modifier, the optional cationic surfactant, the optional nonionic polymer, the optional self-terminating agent, and / or any other additives using any suitable means for preparing such a dispersion; (iii) adjusting the pH of the dispersion as necessary; and (iv) optionally adding appropriate amounts of other optional components and / or additives to the mixture.

[0057] Alternatively, the polishing composition can be prepared by (i) providing one or more components (e.g., cationic polymer, buffer, optional conductivity modifier, optional cationic surfactant, optional non-ionic polymer, optional self-stopping agent, and / or any other additives) in a ceria abrasive slurry; (ii) providing one or more components (e.g., cationic polymer, buffer, optional conductivity modifier, optional cationic surfactant, optional non-ionic polymer, optional self-stopping agent, and / or any other additives) in an additive solution; (iii) combining the ceria abrasive slurry and the additive solution to form a mixture; (iv) optionally adding an appropriate amount of any other additives to the mixture; and (v) adjusting the pH of the mixture as needed.

[0058]

[0058] The polishing composition can be supplied as a one-package system containing ceria abrasive particles, cationic polymer, buffer, optional conductivity modifier, optional cationic surfactant, optional non-ionic polymer, optional self-stopping agent, other optional additives, and water. Alternatively, the polishing composition of the present invention can be supplied as a two-package system containing ceria abrasive slurry in a first package and additive solution in a second package, where the ceria abrasive slurry consists essentially of or consists of ceria abrasive particles and water, and the additive solution consists essentially of or consists of cationic polymer, buffer, optional conductivity modifier, optional cationic surfactant, optional non-ionic polymer, optional self-stopping agent, and / or other optional additives. The two-package system allows the properties of the polishing composition to be adjusted by varying the mixing ratio of the two packages, i.e., ceria abrasive slurry and additive solution.

[0059]

[0059] Various methods can be employed to utilize such a two-package polishing system. For example, the ceria abrasive slurry and the additive solution can be delivered to the polishing table by different piping that are joined and connected at the outlet of the supply piping. The ceria abrasive slurry and the additive solution can be mixed immediately prior to polishing or immediately prior to polishing, or can be delivered simultaneously onto the polishing table. Furthermore, when the two packages are mixed, deionized water can be added as desired to adjust the polishing composition and the resulting substrate polishing properties.

[0060]

[0060] Similarly, in connection with the present invention, three, four or more packaging systems can be utilized, with each of the multiple containers containing different components of the chemical mechanical polishing composition of the present invention, one or more optional components, and / or different concentrations of one or more of the same components.

[0061]

[0061] In order to mix components contained in two or more storage devices to produce a polishing composition at or near the point of use, the storage devices typically include one or more flow lines leading from each storage device to the point of use of the polishing composition (e.g., a platen, a polishing pad, or a substrate surface). As used herein, the term "point-of-use" refers to the point at which the polishing composition is applied to the substrate surface (e.g., a polishing pad or the substrate surface itself). The term "flow line" refers to the flow path from an individual storage container to the point of use of the components stored therein. Each of the flow lines can lead directly to the point of use, or two or more flow lines can be combined at any point into a single flow line leading to the point of use. Additionally, any of the flow lines (e.g., individual flow lines or combined flow lines) can first lead to one or more other devices (e.g., pumping devices, metering devices, mixing devices, etc.) before reaching the point of use of the components.

[0062]

[0062] The components of the polishing composition can be delivered independently to the point of use (e.g., the components are delivered to the substrate surface where the components are mixed during the polishing process), or one or more of the components can be combined prior to delivery to the point of use, e.g., immediately prior to or immediately prior to delivery to the point of use. Components are combined "immediately prior to delivery to the point of use" if they are combined no later than about 5 minutes, e.g., no later than about 4 minutes, no later than about 3 minutes, no later than about 2 minutes, no later than about 1 minute, no later than about 45 seconds, no later than about 30 seconds, no later than about 10 seconds, or simultaneously with delivery of the components at the point of use (e.g., the components are combined in a dispenser). Components are also combined "immediately prior to delivery to the point of use" if they are combined within 5 m of the point of use, e.g., within 1 m of the point of use, or within 10 cm of the point of use (e.g., within 1 cm of the point of use).

[0063]

[0063] When two or more components of the polishing composition are combined before reaching the point of use, the components may be combined in a flow line and delivered to the point of use without the use of a mixing device. Alternatively, one or more flow lines may lead to the mixing device to facilitate the combination of the two or more components. Any suitable mixing device may be used. For example, the mixing device may be a nozzle or jet (e.g., a high-pressure nozzle or jet) through which the two or more components flow. Alternatively, the mixing device may be a vessel-type mixing device that includes one or more inlets through which the two or more components of the polishing slurry are introduced into the mixer and at least one outlet through which the mixed components exit the mixer to be delivered to the point of use directly or via other elements of the device (e.g., via one or more flow lines). Additionally, the mixing device may include two or more chambers, each chamber having at least one inlet and at least one outlet, and the two or more components are combined in each chamber. If a vessel-type mixing device is used, the mixing device preferably includes a mixing mechanism to further facilitate mixing of the components. Mixing mechanisms are commonly known in the art and include stirrers, blenders, agitators, paddle baffles, gas sparger systems, vibrators, and the like.

[0064]

[0064] The polishing composition may also be provided as a concentrate intended to be diluted with an appropriate amount of water prior to use. In such an embodiment, the polishing composition concentrate contains the components of the polishing composition in amounts such that, upon dilution of the concentrate with an appropriate amount of water, each component of the polishing composition is present in the polishing composition in an amount within the appropriate range set forth above for each component. For example, the ceria abrasive particles, cationic polymer, buffer, optional conductivity modifier, optional cationic surfactant, optional nonionic polymer, optional self-terminating agent, and / or any other additives may each be present in the concentrate in an amount about two times (e.g., about three times, about four times, or about five times) higher than the concentrations set forth above for each component, and, upon dilution of the concentrate with an equal volume of water (e.g., 2 equal volumes of water, 3 equal volumes of water, or 4 equal volumes of water, respectively), each component will be present in the polishing composition in an amount within the range set forth above for each component. Additionally, as will be appreciated by those skilled in the art, the concentrate may include an appropriate percentage of water present in the final polishing composition to ensure that the ceria abrasive particles, cationic polymer, buffer, optional conductivity adjuster, optional cationic surfactant, optional non-ionic polymer, optional self-stopping agent, and / or any other additives are at least partially or completely dissolved in the concentrate.

[0065]

[0065] The present invention further provides a method for chemically mechanically polishing a substrate, comprising, consisting essentially of, or consisting of: (i) providing a substrate; (ii) providing a polishing pad; (iii) providing a chemical mechanical polishing composition comprising: (a) ceria abrasive particles; (b) a cationic polymer; (c) a buffering agent; and (d) water, wherein the polishing composition has a pH of from about 3 to about 9; (iv) contacting the substrate with the polishing pad and chemical mechanical polishing composition; and (v) moving the polishing pad and chemical mechanical polishing composition relative to the substrate to abrade at least a portion of the substrate and polish the substrate.

[0066] The chemical mechanical polishing composition can be used to polish any suitable substrate, and is particularly useful for polishing substrates that include at least one layer (typically a surface layer) of a low-k dielectric material. Suitable substrates include wafers used in the semiconductor industry. Wafers typically include or consist of, for example, metals, metal oxides, metal nitrides, metal composites, metal alloys, low-k dielectric materials, or combinations thereof. The method of the present invention is particularly useful for polishing substrates that include silicon oxide, silicon nitride, and / or polysilicon, such as any one or all of the foregoing materials. In some embodiments, the substrate includes silicon oxide, silicon nitride, and polysilicon on a surface of the substrate, and at least a portion of the silicon oxide, silicon nitride, and polysilicon on the surface of the substrate is polished to polish the substrate.

[0067] In certain embodiments, the substrate includes silicon oxide, silicon nitride, and polysilicon. The polysilicon can be any suitable polysilicon, many of which are known in the art. The polysilicon can have any suitable phase, and can be amorphous, crystalline, or a combination thereof. The silicon nitride can be any suitable silicon nitride, many of which are known in the art. The silicon nitride can have any suitable phase, and can be amorphous, crystalline, or a combination thereof. The silicon oxide can likewise be any suitable silicon oxide, many of which are known in the art. Suitable types of silicon oxide include, but are not limited to, borophosphosilicate glass (BPSG), high density plasma (HDP) oxide and / or plasma enhanced tetraethyl orthosilicate (PETEOS) and / or tetraethyl orthosilicate (TEOS), thermal oxide, and undoped silicate glass.

[0068] The chemical mechanical polishing compositions of the present invention can be tailored to provide effective polishing in a desired polishing range that is selective to a particular thin layer material while minimizing surface imperfections, defects, corrosion, erosion, and removal of the stop layer. Selectivity can be controlled to some extent by varying the relative concentrations of the components of the polishing composition.

[0069]

[0069] When desired, the chemical mechanical polishing composition of the present invention can provide non-selective chemical mechanical polishing of a substrate comprising silicon oxide, silicon nitride, and polysilicon. In other words, the polishing composition can provide an approximately 1:1:1 ratio in the relative removal rates of silicon oxide, silicon nitride, and polysilicon. In that regard, the method can provide removal rates of silicon oxide, silicon nitride, and polysilicon, where the silicon oxide removal rate, silicon nitride removal rate, and polysilicon removal rate have an overall average removal rate (i.e., the sum of the silicon oxide removal rate, silicon nitride removal rate, and polysilicon removal rate divided by 3), and each of the silicon oxide removal rate, silicon nitride removal rate, and polysilicon removal rate is within 20% of the overall average removal rate. In some embodiments, the method can provide removal rates of silicon oxide, silicon nitride, and polysilicon, where the silicon oxide removal rate, silicon nitride removal rate, and polysilicon removal rate have an overall average removal rate, and each of the silicon oxide removal rate, silicon nitride removal rate, and polysilicon removal rate is within 15% of the overall average removal rate. In certain embodiments, the method can provide removal rates of silicon oxide, silicon nitride, and polysilicon, where the silicon oxide removal rate, silicon nitride removal rate, and polysilicon removal rate have an overall average removal rate, and each of the silicon oxide removal rate, silicon nitride removal rate, and polysilicon removal rate is within 10% of the overall average removal rate.

[0070]

[0070] Without wishing to be bound by any particular theory, it is believed that the addition of the non-ionic polymer alone or in combination with the cationic surfactant helps to make the polishing composition non-selective, i.e., to maintain similar removal rates for each of silicon oxide, silicon nitride, and polysilicon. Thus, in some aspects, the present invention further provides a method of chemically mechanically polishing a substrate, comprising, consisting essentially of, or consisting of: (i) providing a substrate; (ii) providing a polishing pad; (iii) providing a chemical mechanical polishing composition comprising: (a) ceria abrasive particles; (b) a cationic polymer; (c) a buffering agent; (d) a non-ionic polymer; and (e) water, the polishing composition having a pH of about 6 to about 9 (e.g., a pH of about 7 to about 9); (iv) contacting the substrate with the polishing pad and the chemical mechanical polishing composition; and (v) moving the polishing pad and the chemical mechanical polishing composition relative to the substrate to abrade at least a portion of the substrate and polish the substrate.

[0071]

[0071] Similarly, in certain aspects, the invention further provides a method of chemically mechanically polishing a substrate, comprising, consisting essentially of, or consisting of: (i) providing a substrate; (ii) providing a polishing pad; (iii) providing a chemical mechanical polishing composition comprising: (a) ceria abrasive particles; (b) a cationic polymer; (c) a buffering agent; (d) a cationic surfactant; (e) a nonionic polymer; and (f) water, wherein the polishing composition has a pH of about 6 to about 9 (e.g., a pH of about 7 to about 9); (iv) contacting the substrate with the polishing pad and chemical mechanical polishing composition; and (v) moving the polishing pad and chemical mechanical polishing composition relative to the substrate to abrade at least a portion of the substrate and polish the substrate.

[0072]

[0072] Without wishing to be bound by any particular theory, it is also believed that the addition of a conductivity modifier (e.g., ammonium nitrate or potassium nitrate), alone or in combination with a nonionic polymer and / or cationic surfactant, helps to make the polishing composition non-selective, i.e., to maintain similar removal rates for each of silicon oxide, silicon nitride, and / or polysilicon. Accordingly, in some aspects, the invention further provides a method of chemically mechanically polishing a substrate, comprising, consisting essentially of, or consisting of: (i) providing a substrate; (ii) providing a polishing pad; (iii) providing a chemical mechanical polishing composition comprising: (a) ceria abrasive particles; (b) a cationic polymer; (c) a buffering agent; (d) a conductivity modifier; and (e) water, wherein the polishing composition has a pH of about 6 to about 9 (e.g., a pH of about 7 to about 9); (iv) contacting the substrate with the polishing pad and the chemical mechanical polishing composition; and (v) moving the polishing pad and the chemical mechanical polishing composition relative to the substrate to abrade at least a portion of the substrate and polish the substrate.

[0073]

[0073] When desired, the chemical mechanical polishing composition of the present invention can provide selective chemical mechanical polishing of substrates comprising silicon oxide, silicon nitride, and polysilicon, selectively removing silicon oxide at a reduced rate relative to silicon nitride and polysilicon. In that regard, the method can provide removal rates of silicon oxide, silicon nitride, and polysilicon, where the silicon oxide removal rate, silicon nitride removal rate, and polysilicon removal rate have an overall average removal rate (i.e., the sum of the silicon oxide removal rate, silicon nitride removal rate, and polysilicon removal rate divided by 3), and the silicon oxide removal rate is at least 50% lower than the overall average removal rate. In some embodiments, the method can provide removal rates of silicon oxide, silicon nitride, and polysilicon, where the silicon oxide removal rate, silicon nitride removal rate, and polysilicon removal rate have an overall average removal rate, and the silicon oxide removal rate is at least 60% lower than the overall average removal rate. In certain embodiments, the method can provide silicon oxide, silicon nitride, and polysilicon removal rates that have an overall average removal rate, and the silicon oxide removal rate is at least 70% lower than the overall average removal rate.

[0074]

[0074] Without wishing to be bound by any particular theory, it is believed that (i) the addition of an additional cationic polymer (e.g., polyMADQUAT, polyDADMAC, and / or polyvinylimidazole), and / or (ii) the addition of a cationic surfactant, can selectively remove silicon oxide at a reduced rate relative to silicon nitride and polysilicon. Accordingly, in some aspects, the invention further provides a method of chemically mechanically polishing a substrate, comprising, consisting essentially of, or consisting of: (i) providing a substrate; (ii) providing a polishing pad; (iii) providing a chemical mechanical polishing composition comprising: (a) ceria abrasive particles; (b) a cationic polymer; (c) a buffering agent; (d) a cationic surfactant; and (e) water, wherein the polishing composition has a pH of about 6 to about 9 (e.g., a pH of about 7 to about 9); (iv) contacting the substrate with the polishing pad and the chemical mechanical polishing composition; and (v) moving the polishing pad and the chemical mechanical polishing composition relative to the substrate to abrade at least a portion of the substrate and polish the substrate. Similarly, in some embodiments, the invention further provides a method of chemically mechanically polishing a substrate, comprising, consisting essentially of, or consisting of: (i) providing a substrate; (ii) providing a polishing pad; (iii) providing a chemical mechanical polishing composition comprising: (a) ceria abrasive particles; (b) two or more cationic polymers; (c) a buffering agent; and (d) water, wherein the polishing composition has a pH of about 6 to about 9 (e.g., a pH of about 7 to about 9); (iv) contacting the substrate with the polishing pad and the chemical mechanical polishing composition; and (v) moving the polishing pad and the chemical mechanical polishing composition relative to the substrate to abrade at least a portion of the substrate and polish the substrate.

[0075]

[0075] Without wishing to be bound by any particular theory, it is also believed that the addition of a conductivity modifier (e.g., diallyldimethylammonium chloride, tetrabutylammonium bromide, tetramethylammonium bromide, tetraethylammonium bromide, benzyltrimethylammonium bromide, tetrabutylammonium chloride, tetramethylammonium chloride, tetraethylammonium chloride, benzyltrimethylammonium chloride, tetrabutylammonium acetate, tetramethylammonium acetate, tetraethylammonium acetate, benzyltrimethylammonium acetate, or combinations thereof) can selectively remove silicon oxide at a reduced rate compared to silicon nitride and polysilicon. Accordingly, in some aspects, the invention further provides a method of chemically mechanically polishing a substrate, comprising, consisting essentially of, or consisting of: (i) providing a substrate; (ii) providing a polishing pad; (iii) providing a chemical mechanical polishing composition comprising: (a) ceria abrasive particles; (b) a cationic polymer; (c) a buffering agent; (d) a conductivity modifier; and (e) water, wherein the polishing composition has a pH of about 6 to about 9 (e.g., a pH of about 7 to about 9); (iv) contacting the substrate with the polishing pad and the chemical mechanical polishing composition; and (v) moving the polishing pad and the chemical mechanical polishing composition relative to the substrate to abrade at least a portion of the substrate and polish the substrate.

[0076]

[0076] When desired, the chemical mechanical polishing composition of the present invention can provide selective chemical mechanical polishing of substrates comprising silicon oxide, silicon nitride, and polysilicon, selectively removing silicon nitride at a reduced rate relative to silicon oxide and polysilicon. In that regard, the method can provide removal rates of silicon oxide, silicon nitride, and polysilicon, where the silicon oxide removal rate, silicon nitride removal rate, and polysilicon removal rate have an overall average removal rate (i.e., the sum of the silicon oxide removal rate, silicon nitride removal rate, and polysilicon removal rate divided by 3), and the silicon nitride removal rate is at least 50% lower than the overall average removal rate. In some embodiments, the method can provide removal rates of silicon oxide, silicon nitride, and polysilicon, where the silicon oxide removal rate, silicon nitride removal rate, and polysilicon removal rate have an overall average removal rate, and the silicon nitride removal rate is at least 60% lower than the overall average removal rate. In certain embodiments, the method can provide silicon oxide, silicon nitride, and polysilicon removal rates that have an overall average removal rate, and the silicon nitride removal rate is at least 70% lower than the overall average removal rate.

[0077]

[0077] Without wishing to be bound by any particular theory, it is believed that the addition of the self-terminating agent allows the silicon nitride to be selectively removed at a reduced rate relative to silicon oxide and polysilicon. Thus, in some aspects, the present invention further provides a method of chemically mechanically polishing a substrate, comprising, consisting essentially of, or consisting of: (i) providing a substrate; (ii) providing a polishing pad; (iii) providing a chemical mechanical polishing composition comprising: (a) ceria abrasive particles; (b) a cationic polymer; (c) a buffering agent; (d) a self-terminating agent; and (e) water, the polishing composition having a pH of about 6 to about 9 (e.g., a pH of about 7 to about 9); (iv) contacting the substrate with the polishing pad and the chemical mechanical polishing composition; and (v) moving the polishing pad and the chemical mechanical polishing composition relative to the substrate to abrade at least a portion of the substrate and polish the substrate.

[0078]

[0078] When desired, the chemical mechanical polishing composition of the present invention can provide selective chemical mechanical polishing of substrates comprising silicon oxide, silicon nitride, and polysilicon, selectively removing polysilicon at a reduced rate relative to silicon oxide and silicon nitride. In that regard, the method can provide removal rates of silicon oxide, silicon nitride, and polysilicon, where the silicon oxide removal rate, silicon nitride removal rate, and polysilicon removal rate have an overall average removal rate (i.e., the sum of the silicon oxide removal rate, silicon nitride removal rate, and polysilicon removal rate divided by 3), and the polysilicon removal rate is at least 50% lower than the overall average removal rate. In some embodiments, the method can provide removal rates of silicon oxide, silicon nitride, and polysilicon, where the silicon oxide removal rate, silicon nitride removal rate, and polysilicon removal rate have an overall average removal rate, and the polysilicon removal rate is at least 60% lower than the overall average removal rate. In certain embodiments, the method can provide silicon oxide, silicon nitride, and polysilicon removal rates that have an overall average removal rate, and the polysilicon removal rate is at least 70% lower than the overall average removal rate.

[0079]

[0079] Without wishing to be bound by any particular theory, it is believed that the addition of the non-ionic polymer allows for the selective removal of polysilicon at a reduced rate relative to silicon oxide and silicon nitride. Thus, in some aspects, the present invention further provides a method of chemically mechanically polishing a substrate, comprising, consisting essentially of, or consisting of: (i) providing a substrate; (ii) providing a polishing pad; (iii) providing a chemical mechanical polishing composition comprising: (a) ceria abrasive particles; (b) a cationic polymer; (c) a buffering agent; (d) a non-ionic polymer; and (e) water, the polishing composition having a pH of about 6 to about 9 (e.g., a pH of about 7 to about 9); (iv) contacting the substrate with the polishing pad and the chemical mechanical polishing composition; and (v) moving the polishing pad and the chemical mechanical polishing composition relative to the substrate to abrade at least a portion of the substrate and polish the substrate.

[0080]

[0080] When desired, the chemical mechanical polishing composition of the present invention can provide selective chemical mechanical polishing of substrates comprising silicon oxide, silicon nitride, and polysilicon, selectively removing each of silicon oxide and silicon nitride at a reduced rate relative to polysilicon. In that regard, the method can provide removal rates of silicon oxide, silicon nitride, and polysilicon, where the silicon oxide removal rate, silicon nitride removal rate, and polysilicon removal rate have an overall average removal rate (i.e., the sum of the silicon oxide removal rate, silicon nitride removal rate, and polysilicon removal rate divided by 3), and where each of the silicon oxide removal rate and silicon nitride removal rate is at least 50% lower than the overall average removal rate. In some embodiments, the method can provide removal rates of silicon oxide, silicon nitride, and polysilicon, where the silicon oxide removal rate, silicon nitride removal rate, and polysilicon removal rate have an overall average removal rate, and where each of the silicon oxide removal rate and silicon nitride removal rate is at least 60% lower than the overall average removal rate. In certain embodiments, the method can provide silicon oxide, silicon nitride, and polysilicon removal rates that have an overall average removal rate, and each of the silicon oxide and silicon nitride removal rates is at least 70% lower than the overall average removal rate.

[0081]

[0081] The polishing composition of the present invention desirably exhibits low particle defects when polishing a substrate, as determined by a suitable technique. In a preferred embodiment, the chemical mechanical polishing composition of the present invention includes wet process ceria, which contributes to a low defectivity. Particle defects on a substrate polished with the polishing composition of the present invention can be determined by any suitable technique. For example, laser light scattering techniques such as dark field normal beam composite (DCN) and dark field oblique beam composite (DCO) can be used to determine particle defects on a polished substrate. Suitable instruments for evaluating particle defectivity are available, for example, from KLA-Tencor (e.g., SURFSCAN™ SPI instruments operating at a threshold of 120 nm or a threshold of 160 nm).

[0082] Substrates polished with the polishing compositions of the present invention, particularly silicon, including silicon oxide, silicon nitride, and / or polysilicon, desirably have DCN values ​​of about 20,000 counts or less, e.g., about 17,500 counts or less, about 15,000 counts or less, about 12,500 counts or less, about 3,500 counts or less, about 3,000 counts or less, about 2,500 counts or less, about 2,000 counts or less, about 1,500 counts or less, or about 1,000 counts or less. Preferably, substrates polished in accordance with embodiments of the present invention have DCN values ​​of about 750 counts or less, e.g., about 500 counts or less, about 250 counts or less, about 125 counts or less, or about 100 counts or less.

[0083] Alternatively or additionally, substrates polished with the chemical mechanical polishing compositions of the present invention desirably exhibit low scratches as determined by a suitable technique. For example, silicon wafers polished according to embodiments of the present invention desirably have no more than about 250 scratches, or no more than about 125 scratches, as determined by any suitable method known in the art, such as, for example, laser light scattering techniques.

[0084] The chemical mechanical polishing compositions and methods of the present invention are particularly suitable for use in conjunction with a chemical mechanical polishing apparatus. Typically, the apparatus includes a platen that is in motion during use and has a velocity resulting from an orbital, linear, or circular motion, a polishing pad that contacts the platen and moves with the platen during the motion, and a carrier that holds a substrate to be polished by contacting and moving the substrate against a surface of the polishing pad. The substrate is polished by contacting the substrate with the polishing pad and the polishing composition of the present invention, and then moving the polishing pad relative to the substrate to abrade at least a portion of the substrate to polish the substrate.

[0085]

[0085] The substrate can be polished with the chemical mechanical polishing composition using any suitable polishing pad (e.g., polishing surface). Suitable polishing pads include, for example, woven and non-woven polishing pads. Furthermore, suitable polishing pads can include any suitable polymer having a variety of densities, hardnesses, thicknesses, compressibility, rebound ability upon compression, and compression moduli. Suitable polymers include, for example, polyvinyl chloride, polyvinyl fluoride, nylon, fluorocarbon, polycarbonate, polyester, polyacrylate, polyether, polyethylene, polyamide, polyurethane, polystyrene, polypropylene, co-formed products thereof, and mixtures thereof. Soft polyurethane polishing pads are particularly useful in conjunction with the polishing method of the present invention. Representative pads include, but are not limited to, SURFIN™ 000, SURFIN™ SSW1, SPM3100 Eminess Technologies), POLITEX™ available from Dow Chemical Company, Newark, DE, POLYPAS™ 27 available from Fujibo, Osaka, JP, EPIC™ D100 pad or NEXPLANAR™ E6088 available from Cabot Microelectronics, Aurora, IL. A preferred polishing pad is a hard microporous polyurethane pad (IC1010™) available from Dow Chemical.

[0086]

[0086] Preferably, the chemical mechanical polishing apparatus further includes an in-situ polishing endpoint detection system, many of which are known in the art. Techniques for inspecting and monitoring the polishing process by analyzing light or other radiation reflected from the surface of the substrate being polished are known in the art. Such methods are described, for example, in U.S. Pat. Nos. 5,196,353, 5,433,651, 5,609,511, 5,643,046, 5,658,183, 5,730,642, 5,838,447, 5,872,633, 5,893,796, 5,949,927, and 5,964,643. Desirably, inspecting or monitoring the progress of the polishing process with respect to the substrate being polished allows for the determination of the polishing endpoint, i.e., when to terminate the polishing process with respect to a particular substrate.

[0087] Embodiment (1) In embodiment (1), (a) Ceria abrasive particles; (b) a cationic polymer; (c) a buffering agent; and (d) water A chemical mechanical polishing composition is provided comprising:

[0088] (2) In embodiment (2), there is provided a polishing composition as described in embodiment (1), wherein the polishing composition comprises from about 0.001% to about 10% by weight of ceria abrasive particles.

[0089] (3) In embodiment (3), there is provided a polishing composition as described in embodiment (1) or embodiment (2), wherein the polishing composition comprises from about 0.05% to about 5% by weight of ceria abrasive particles.

[0090]

[0090] (4) In embodiment (4), there is provided a polishing composition according to any one of embodiments (1) to (3), wherein the polishing composition has a pH of about 7 to about 9.

[0091]

[0091] (5) In embodiment (5), there is provided a polishing composition according to any one of embodiments (1) to (4), wherein the polishing composition has a pH of about 7 to about 8.

[0092]

[0092] (6) In embodiment (6), there is provided a polishing composition described in any one of embodiments (1) to (5), wherein the polishing composition further contains a nonionic polymer selected from polyalkylene glycols, polyether amines, polyethylene oxide / polypropylene oxide copolymers, polyacrylamides, polyvinylpyrrolidones, siloxane polyalkylene oxide copolymers, hydrophobically modified polyacrylate copolymers, hydrophilic nonionic polymers, polysaccharides, and combinations thereof.

[0093] (7) In embodiment (7), there is provided the polishing composition according to embodiment (6), wherein the nonionic polymer is polyvinylpyrrolidone.

[0094] (8) In embodiment (8), there is provided the polishing composition according to embodiment (6), wherein the nonionic polymer is a polyalkylene glycol.

[0095] (9) In embodiment (9), there is provided the polishing composition according to embodiment (6), wherein the nonionic polymer is a polyethylene oxide / polypropylene oxide copolymer.

[0096] (10) In embodiment (10), the cationic polymer is selected from the group consisting of N-vinylimidazole, 2-(dimethylamino)ethyl acrylate ("DMAEA"), 2-(dimethylamino)ethyl methacrylate ("DMAEM"), 3-(dimethylamino)propyl methacrylamide ("DMAPMA"), 3-(dimethylamino)propyl acrylamide ("DMAPA"), 3-methacrylamidopropyl-trimethyl-ammonium chloride ("MAPTAC"), 3-acrylamidopropyl-trimethyl-ammonium chloride ("APTAC"), diallyldimethylammonium chloride ( The polishing composition of any one of embodiments (1) to (9) is provided, comprising a cationic monomer selected from N,N-dimethylaminoethyl acrylate benzyl chloride ("DMAEA.BCQ"), 2-(acryloyloxy)-N,N,N-trimethylethanaminium chloride ("DMAEA.MCQ"), 2-(methacryloyloxy)-N,N,N-trimethylethanaminium chloride ("DMAEM.MCQ"), N,N-dimethylaminoethyl acrylate benzyl chloride ("DMAEA.BCQ"), salts thereof, and combinations thereof.

[0097]

[0097] (11) In embodiment (11), a polishing composition described in embodiment (10) is provided, wherein the cationic monomer is selected from N-vinylimidazole, diallyldimethylammonium chloride ("DADMAC"), 2-(methacryloyloxy)-N,N,N-trimethylethanaminium chloride ("DMAEM.MCQ"), salts thereof, and combinations thereof.

[0098]

[0098] (12) In embodiment (12), there is provided the polishing composition of any one of embodiments (1) to (11), wherein the buffer is an amine-based compound containing 1 to 5 nitrogen atoms.

[0099]

[0099] (13) In embodiment (13), there is provided a polishing composition described in any one of embodiments (1) to (12), wherein the buffer is a heterocyclic or heteroaromatic amine compound containing 1 to 5 nitrogen atoms.

[0100]

[0100] (14) In embodiment (14), there is provided a polishing composition according to any one of embodiments (1) to (13), wherein the buffer comprises a heterocyclic or heteroaromatic amine selected from pyrrole, pyrrolidine, carbazole, isoindole, indole, pyrroline, indolizine, indoline, pyridine, piperidine, quinolizine, isoquinoline, quinoline, naphthyridine, imidazole, imidazoline, imidazolidine, tetrazole, triazole, benimidazole, purine, benzoxazole, benzthiazole, isothiazole, isoxazole, thiazole, oxazole, morpholine, thiomorpholine, pyrazole, pyrazoline, pteridine, triazine, pyrimidine, pyrazine, piperazine, indazole, pyridazine, and combinations thereof.

[0101]

[0101] (15) In embodiment (15), there is provided the polishing composition of any one of embodiments (1) to (14), wherein the buffer is benzotriazole, 5-aminotetrazole, or a combination thereof.

[0102]

[0102] (16) In embodiment (16), there is provided the polishing composition of any one of embodiments (1) to (15), wherein the polishing composition further comprises a cationic surfactant.

[0103]

[0103] (17) In embodiment (17), there is provided the polishing composition of embodiment (16), wherein the cationic surfactant comprises a quaternary ammonium salt.

[0104]

[0104] (18) In embodiment (18), there is provided a polishing composition described in embodiment (16) or embodiment (17), wherein the cationic surfactant is selected from N,N,N',N',N'-pentamethyl-N-tallow alkyl-1,3-propanediammonium dichloride, (oxydi-2,1-ethanediyl)bis(cocoalkyl)dimethylammonium dichloride, salts thereof, and combinations thereof.

[0105]

[0105] (19) In embodiment (19), the polishing composition according to any one of embodiments (1) to (18) further comprises a compound represented by formula (I): A polishing composition is presented, further comprising a self-terminating agent of the formula: TIFF2025505182000002.tif25170, where R is selected from hydrogen, alkyl, heteroalkyl, cycloalkyl, heterocycloalkyl, aryl, and heteroaryl, each of which may be substituted or unsubstituted.

[0106]

[0106] (20) In embodiment (20), there is provided the polishing composition of embodiment (19), wherein the self-terminating agent is selected from hydroxamic acid, acetohydroxamic acid, benzhydroxamic acid, salicylhydroxamic acid, and combinations thereof.

[0107]

[0107] (21) In embodiment (21), there is provided the polishing composition according to embodiment (19) or embodiment (20), wherein the self-terminating agent is a hydroxamic acid.

[0108]

[0108] (22) In embodiment (22), there is provided the polishing composition according to embodiment (19) or embodiment (20), wherein the self-terminating agent is benzhydroxamic acid.

[0109]

[0109] (23) In embodiment (23), there is provided the polishing composition according to embodiment (19) or embodiment (20), wherein the self-terminating agent is salicylhydroxamic acid.

[0110]

[0110] (24) In embodiment (24), there is provided a polishing composition described in any one of embodiments (1) to (23), wherein the polishing composition further contains a conductivity adjuster selected from ammonium salts, potassium salts, and combinations thereof.

[0111]

[0111] (25) In embodiment (25), there is provided a polishing composition described in embodiment (24), wherein the conductivity adjuster has a counterion selected from nitrate, acetate, halide, phosphate, and sulfate.

[0112]

[0112] (26) In embodiment (26), there is provided a polishing composition as described in embodiment (24) or embodiment (25), wherein the conductivity adjuster is selected from ammonium nitrate, ammonium chloride, ammonium bromide, ammonium acetate, potassium nitrate, potassium chloride, potassium bromide, potassium acetate, diallyldimethylammonium chloride, tetrabutylammonium bromide, tetramethylammonium bromide, tetraethylammonium bromide, benzyltrimethylammonium bromide, tetrabutylammonium chloride, tetramethylammonium chloride, tetraethylammonium chloride, benzyltrimethylammonium chloride, tetrabutylammonium acetate, tetramethylammonium acetate, tetraethylammonium acetate, benzyltrimethylammonium acetate, and combinations thereof.

[0113]

[0113] (27) In embodiment (27), there is provided a polishing composition according to any one of embodiments (1) to (26), wherein the polishing composition has a conductivity of at least 170 μS / cm.

[0114]

[0114] (28) In embodiment (28), there is provided the polishing composition of any one of embodiments (1) to (27), wherein the polishing composition has a conductivity of at least 350 μS / cm.

[0115] (29) In embodiment (29), there is provided a method for chemically mechanically polishing a substrate, comprising the steps of: (i) providing a substrate; (ii) providing a polishing pad; (iii) (a) Ceria abrasive particles; (b) a cationic polymer; (c) a buffering agent; and (d) water a chemical mechanical polishing composition comprising: (iv) contacting the substrate with the polishing pad and the chemical mechanical polishing composition; and (v) moving the polishing pad and the chemical-mechanical polishing composition relative to the substrate to abrade at least a portion of the substrate, thereby polishing the substrate.

[0116]

[0116] (30) In embodiment (30), the method of embodiment (29) is presented, wherein the polishing composition comprises about 0.001% to about 10% by weight of ceria abrasive particles.

[0117]

[0117] (31) In embodiment (31), the method of embodiment (29) or embodiment (30) is presented, wherein the polishing composition comprises about 0.05% to about 5% by weight of ceria abrasive particles.

[0118]

[0118] (32) In embodiment (32), the method of any one of embodiments (29) to (31) is provided, wherein the polishing composition has a pH of about 7 to about 9.

[0119]

[0119] (33) In embodiment (33), the method of any one of embodiments (29) to (32) is provided, wherein the polishing composition has a pH of about 7 to about 8.

[0120] (34) In embodiment (34), the cationic polymer is selected from the group consisting of N-vinylimidazole, 2-(dimethylamino)ethyl acrylate ("DMAEA"), 2-(dimethylamino)ethyl methacrylate ("DMAEM"), 3-(dimethylamino)propyl methacrylamide ("DMAPMA"), 3-(dimethylamino)propyl acrylamide ("DMAPA"), 3-methacrylamidopropyl-trimethyl-ammonium chloride ("MAPTAC"), 3-acrylamidopropyl-trimethyl-ammonium chloride ("APTAC"), diallyldimethylammonium chloride, The method of any one of embodiments (29)-(33) is provided, comprising a cationic monomer selected from N,N,N-dimethylaminoethyl acrylate benzyl chloride ("DMAEA.BCQ"), N,N-dimethylaminoethyl methacrylate benzyl chloride ("DMAEM.BCQ"), salts thereof, and combinations thereof.

[0121]

[0121] (35) In embodiment (35), the method of embodiment (34) is provided, wherein the cationic monomer is selected from N-vinylimidazole, diallyldimethylammonium chloride ("DADMAC"), 2-(methacryloyloxy)-N,N,N-trimethylethanaminium chloride ("DMAEM.MCQ"), salts thereof, and combinations thereof.

[0122]

[0122] (36) In embodiment (36), the method of any one of embodiments (29) to (35) is provided, wherein the buffer is an amine-based compound containing 1 to 5 nitrogen atoms.

[0123]

[0123] (37) In embodiment (37), the method of any one of embodiments (29) to (36) is provided, wherein the buffer is a heterocyclic or heteroaromatic amine compound containing 1 to 5 nitrogen atoms.

[0124]

[0124] (38) In embodiment (38), the method of any one of embodiments (29)-(37) is provided, wherein the buffer comprises a heterocyclic or heteroaromatic amine selected from pyrrole, pyrrolidine, carbazole, isoindole, indole, pyrroline, indolizine, indoline, pyridine, piperidine, quinolizine, isoquinoline, quinoline, naphthyridine, imidazole, imidazoline, imidazolidine, tetrazole, triazole, benimidazole, purine, benzoxazole, benzthiazole, isothiazole, isoxazole, thiazole, oxazole, morpholine, thiomorpholine, pyrazole, pyrazoline, pteridine, triazine, pyrimidine, pyrazine, piperazine, indazole, pyridazine, and combinations thereof.

[0125]

[0125] (39) In embodiment (39), the method of any one of embodiments (29) to (38) is provided, wherein the buffering agent is benzotriazole, 5-aminotetrazole, or a combination thereof.

[0126]

[0126] (40) In embodiment (40), a method according to any one of embodiments (29) to (39) is provided, wherein the polishing composition further comprises a conductivity adjuster selected from ammonium salts, potassium salts, and combinations thereof.

[0127]

[0127] (41) In embodiment (41), the method of embodiment (40) is provided, wherein the conductivity adjuster has a counterion selected from nitrate, acetate, halide, phosphate, and sulfate.

[0128]

[0128] (42) In embodiment (42), the method of embodiment (40) or embodiment (41) is provided, wherein the conductivity adjuster is selected from ammonium nitrate, ammonium chloride, ammonium bromide, ammonium acetate, potassium nitrate, potassium chloride, potassium bromide, potassium acetate, diallyldimethylammonium chloride, tetrabutylammonium bromide, tetramethylammonium bromide, tetraethylammonium bromide, benzyltrimethylammonium bromide, tetrabutylammonium chloride, tetramethylammonium chloride, tetraethylammonium chloride, benzyltrimethylammonium chloride, tetrabutylammonium acetate, tetramethylammonium acetate, tetraethylammonium acetate, benzyltrimethylammonium acetate, and combinations thereof.

[0129]

[0129] (43) In embodiment (43), the method of any one of embodiments (29) to (42) is provided, wherein the polishing composition has a conductivity of at least 170 μS / cm.

[0130]

[0130] (44) In embodiment (44), the method of any one of embodiments (29) to (43) is provided, wherein the polishing composition has a conductivity of at least 350 μS / cm.

[0131]

[0131] (45) In embodiment (45), a method according to any one of embodiments (29) to (44) is provided, wherein the substrate comprises silicon oxide, silicon nitride, and polysilicon, and at least a portion of the silicon oxide, silicon nitride, or polysilicon is polished at a silicon oxide removal rate, a silicon nitride removal rate, and a polysilicon removal rate to polish the substrate.

[0132]

[0132] (46) In embodiment (46), a method as described in embodiment (45) is presented, in which the silicon oxide removal rate, the silicon nitride removal rate, and the polysilicon removal rate have an overall average removal rate, and each of the silicon oxide removal rate, the silicon nitride removal rate, and the polysilicon removal rate is within 20% of the overall average removal rate.

[0133]

[0133] (47) In embodiment (47), a method as described in embodiment (45) is presented, in which the silicon oxide removal rate, the silicon nitride removal rate, and the polysilicon removal rate have an overall average removal rate, and each of the silicon oxide removal rate, the silicon nitride removal rate, and the polysilicon removal rate is within 15% of the overall average removal rate.

[0134]

[0134] (48) In embodiment (48), a method as described in embodiment (45) is presented, in which the silicon oxide removal rate, the silicon nitride removal rate, and the polysilicon removal rate have an overall average removal rate, and each of the silicon oxide removal rate, the silicon nitride removal rate, and the polysilicon removal rate is within 10% of the overall average removal rate.

[0135]

[0135] (49) In embodiment (49), a method according to any one of embodiments (29) to (45) is presented, wherein the polishing composition further comprises a nonionic polymer selected from polyalkylene glycols, polyether amines, polyethylene oxide / polypropylene oxide copolymers, polyacrylamides, polyvinylpyrrolidones, siloxane polyalkylene oxide copolymers, hydrophobically modified polyacrylate copolymers, hydrophilic nonionic polymers, polysaccharides, and combinations thereof.

[0136]

[0136] (50) In embodiment (50), the method of embodiment (49) is provided, wherein the nonionic polymer is polyvinylpyrrolidone.

[0137]

[0137] (51) In embodiment (51), the method of embodiment (49) is provided, wherein the nonionic polymer is a polyalkylene glycol.

[0138]

[0138] (52) In embodiment (52), the method of embodiment (49) is provided, wherein the nonionic polymer is a polyethylene oxide / polypropylene oxide copolymer.

[0139]

[0139] (53) In embodiment (53), a method according to any one of embodiments (49) to (52) is provided, wherein the substrate comprises silicon oxide, silicon nitride, and polysilicon, and at least a portion of the silicon oxide, silicon nitride, or polysilicon is polished at removal rates to polish the substrate at a silicon oxide removal rate, a silicon nitride removal rate, and a polysilicon removal rate, and the silicon oxide removal rate, the silicon nitride removal rate, and the polysilicon removal rate have an overall average removal rate, and the polysilicon removal rate is at least 50% lower than the overall average removal rate.

[0140]

[0140] (54) In embodiment (54), the method described in embodiment (53) is presented, wherein the silicon oxide removal rate, the silicon nitride removal rate, and the polysilicon removal rate have an overall average removal rate, and the polysilicon removal rate is at least 60% lower than the overall average removal rate.

[0141]

[0141] (55) In embodiment (55), a method as described in embodiment (5e) is provided, in which the silicon oxide removal rate, the silicon nitride removal rate, and the polysilicon removal rate have an overall average removal rate, and the polysilicon removal rate is at least 70% lower than the overall average removal rate.

[0142]

[0142] (56) In embodiment (56), the method according to any one of embodiments (29)-(45) and (49)-(52) is provided, wherein the polishing composition further comprises a cationic surfactant.

[0143]

[0143] (57) In embodiment (57), the method of embodiment (56) is provided, wherein the cationic surfactant comprises a quaternary ammonium salt.

[0144]

[0144] (58) In embodiment (58), the method described in embodiment (56) or embodiment (57) is provided, wherein the cationic surfactant is selected from N,N,N',N',N'-pentamethyl-N-tallow alkyl-1,3-propanediammonium dichloride, (oxydi-2,1-ethanediyl)bis(cocoalkyl)dimethylammonium dichloride, salts thereof, and combinations thereof.

[0145]

[0145] (59) In embodiment (59), the method of any one of embodiments (29)-(45), (49)-(52), and (56)-(58) is provided, wherein the polishing composition comprises two or more cationic polymers.

[0146]

[0146] (60) In embodiment (60), there is provided the method of any one of embodiments (29)-(45), (49)-(52), and (56)-(59), wherein the conductivity adjuster is selected from diallyldimethylammonium chloride, tetrabutylammonium bromide, tetramethylammonium bromide, tetraethylammonium bromide, benzyltrimethylammonium bromide, tetrabutylammonium chloride, tetramethylammonium chloride, tetraethylammonium chloride, benzyltrimethylammonium chloride, tetrabutylammonium acetate, tetramethylammonium acetate, tetraethylammonium acetate, benzyltrimethylammonium acetate, and combinations thereof.

[0147]

[0147] (61) In embodiment (61), there is provided a method according to any one of embodiments (56) to (60), wherein the substrate comprises silicon oxide, silicon nitride, and polysilicon, and at least a portion of the silicon oxide, silicon nitride, or polysilicon is polished at removal rates to polish the substrate at a silicon oxide removal rate, a silicon nitride removal rate, and a polysilicon removal rate, and the silicon oxide removal rate, the silicon nitride removal rate, and the polysilicon removal rate have an overall average removal rate, and the silicon oxide removal rate is at least 50% lower than the overall average removal rate.

[0148]

[0148] (62) In embodiment (62), a method as described in embodiment (61) is provided, in which the silicon oxide removal rate, the silicon nitride removal rate, and the polysilicon removal rate have an overall average removal rate, and the silicon oxide removal rate is at least 60% lower than the overall average removal rate.

[0149]

[0149] (63) In embodiment (63), a method as described in embodiment (61) is provided, in which the silicon oxide removal rate, the silicon nitride removal rate, and the polysilicon removal rate have an overall average removal rate, and the silicon oxide removal rate is at least 70% lower than the overall average removal rate.

[0150]

[0150] (64) In embodiment (64), the method of any one of embodiments (29) to (45), (49) to (52), and (56) to (63) is characterized in that the polishing composition is a compound represented by formula (I): A method is presented, further comprising a self-terminating agent of the formula: TIFF2025505182000003.tif25170, wherein R is selected from hydrogen, alkyl, heteroalkyl, cycloalkyl, heterocycloalkyl, aryl, and heteroaryl, each of which may be substituted or unsubstituted.

[0151]

[0151] (65) In embodiment (65), the method of embodiment (64) is provided, wherein the self-terminating agent is selected from hydroxamic acid, acetohydroxamic acid, benzhydroxamic acid, salicylhydroxamic acid, and combinations thereof.

[0152]

[0152] (66) In embodiment (66), the method of embodiment (64) or embodiment (65) is provided, wherein the self-terminating agent is a hydroxamic acid.

[0153]

[0153] (67) In embodiment (67), the method of embodiment (64) or embodiment (65) is provided, wherein the self-terminating agent is benzhydroxamic acid.

[0154]

[0154] (68) In embodiment (68), the method of embodiment (64) or embodiment (65) is provided, wherein the self-terminating agent is salicylhydroxamic acid.

[0155]

[0155] (69) In embodiment (69), there is provided a method according to any one of embodiments (64) to (68), wherein the substrate comprises silicon oxide, silicon nitride, and polysilicon, and at least a portion of the silicon oxide, silicon nitride, or polysilicon is polished at removal rates to polish the substrate at a silicon oxide removal rate, a silicon nitride removal rate, and a polysilicon removal rate, and wherein the silicon oxide removal rate, the silicon nitride removal rate, and the polysilicon removal rate have an overall average removal rate, and the silicon nitride removal rate is at least 50% lower than the overall average removal rate.

[0156]

[0156] (70) In embodiment (70), a method as described in embodiment (69) is provided, in which the silicon oxide removal rate, the silicon nitride removal rate, and the polysilicon removal rate have an overall average removal rate, and the silicon nitride removal rate is at least 60% lower than the overall average removal rate.

[0157]

[0157] (71) In embodiment (71), a method as described in embodiment (69) is provided, in which the silicon oxide removal rate, the silicon nitride removal rate, and the polysilicon removal rate have an overall average removal rate, and the silicon nitride removal rate is at least 70% lower than the overall average removal rate. EXAMPLES

[0158] Working Example

[0158] These following examples further illustrate the invention but, of course, should not be construed as in any way limiting its scope.

[0159]

[0159] The following abbreviations are used throughout the examples: removal rate (RR); tetraethylorthosilicate (TEOS); silicon nitride (SiN); polysilicon (polySi); molecular weight (MW); and polyethylene glycol (PEG).

[0160] In the following examples, substrates, TEOS (i.e., silicon oxide), polySi, or SiN, were coated on silicon and polished using a MIRRA™ (Applied Materials, Inc.) polishing tool, an AP-300™ (CTS Co., Ltd.) polishing tool, or a REFLEXION™ (Applied Materials, Inc.) polishing tool. An IC1010™ polishing pad (Rohm and Haas Electronic Materials) or a NEXPLANAR™ E6088 polishing pad (Cabot Microelectronics, Aurora, IL) was used with the same polishing parameters for all compositions.

[0161]

[0161] Unless otherwise stated, standard REFLEXION™ polishing parameters are as follows: IC1010™ pad, down force = 20.68 kPa (3 psi), head speed = 85 rpm, platen speed = 100 rpm, and total flow rate = 250 mL / min.

[0162]

[0162] Unless otherwise stated, standard AP-300™ polishing parameters are as follows: IC1010™ pad, down force = 20.68 kPa (3 psi), head speed = 85 rpm, platen speed = 100 rpm, and total flow rate = 250 mL / min.

[0163]

[0163] Unless otherwise specified, standard MIRRA (trademark) polishing is as follows: IC1010 (trademark) pad, downforce = 20.68 kPa (3 psi), head speed = 85 rpm, platen speed = 100 rpm, and total flow rate = 250 mL / min; or NEXPLANAR (trademark) E6088 pad downforce = 13.79 kPa (2 psi), head speed = 85 rpm, platen speed = 100 rpm, and total flow rate = 250 mL / min.

[0164]

[0164] The removal rate was calculated by measuring the film thickness using spectroscopic ellipsometry and subtracting the final thickness from the initial thickness.

[0165] Example 1 This example illustrates the preparation of polishing compositions according to the present invention comprising (a) ceria abrasive particles, (b) a cationic polymer, and (c) a buffering agent, and optionally a cationic surfactant, a nonionic polymer, and / or a self-terminating agent. Polishing Compositions 1A-1O of the present invention were used in Examples 2 and 3 below to demonstrate the efficacy of the claimed polishing method.

[0166]

[0166] For each of the inventive polishing compositions 1A-1O used in Examples 2 and 3, ceria particles HC30™ and HC60™ (commercially available from Rhodia) were added in the amounts shown in Table 1, e.g., for polishing composition 1A, 0.16 wt. % HC30™ and 0.16 wt. % HC60™ were added. The ceria particles were combined with a cationic polymer (polydiallyldimethylammonium chloride ("PolyDADMAC") and / or poly-2-(methacryloyloxy)-N,N,N-trimethylethanaminium chloride ("PolyMADQUAT") for each of polishing compositions 1A-1O) and a buffer (1H-benzotriazole ("BTA") for each of polishing compositions 1A-1O). A biocide was further added to each of the inventive polishing compositions 1A-1O, and the pH was adjusted to 7.5 with triethanolamine.

[0167]

[0167] Polishing Compositions 1B-1F, 1I, 1J, 1N, and 1O of the present invention further contained the cationic surfactant N,N,N',N',N'-pentamethyl-N-tallowalkyl-1,3-propanediammonium dichloride ("Duoquad T-50 HF") in the amount shown in Table 1.

[0168]

[0168] Polishing Compositions 1C to 1J of the present invention further contained one or more nonionic polymers selected from PEG300, PEG1000, PEG4000, and PEG8000 in the amounts shown in Table 1.

[0169]

[0169] Polishing Compositions 1K-1O of the present invention further contained one or more self-terminating agents selected from salicylhydroxamic acid ("SHA") and benzhydroxamic acid ("BHA") in the amounts shown in Table 1.

[0170]

[0170] The resulting compositions are summarized in Table 1. TIFF2025505182000004.tif211170

[0171] Example 2

[0171] This example demonstrates the beneficial polishing performance provided by polishing compositions containing cationic surfactants and / or nonionic polymers prepared in accordance with the present invention.

[0172]

[0172] Patterned substrates containing TEOS, SiN, or polySi were polished using polishing compositions 1A-1E defined in Table 1 of Example 1 on a 300 mm AP-300™ (CTS Co., Ltd) polishing tool with an IC1010™ pad (Rohm and Haas Electronic Materials) and a Saesol C7 conditioner (Saesol Diamond Ind. Co., Ltd, South Korea) using the following parameters: platen speed of 93 rpm, head speed of 87 rpm, and slurry flow rate of 250 ml / min. The polishing time was 30 seconds. After polishing, the RR of TEOS, SiN, and polySi was measured, and the results are shown in Table 2. TIFF2025505182000005.tif136170

[0173]

[0173] As can be seen from Table 2, the polishing composition of the present invention 1A containing only HC-60™, HC-30™, polyMADQUAT and BTA exhibited removal rates of 5682 Å / min and 3028 Å / min for silicon oxide (i.e., TEOS), which were relatively fast compared to the removal rate of silicon nitride (1904 Å / min).

[0174]

[0174] Table 2 also shows that the addition of a cationic surfactant, such as N,N,N',N',N'-pentamethyl-N-tallow alkyl-1,3-propanediammonium dichloride ("Duoquad T-50 HF"), reduces the polishing removal rate of silicon oxide (i.e., TEOS) while maintaining the removal rate of polysilicon and silicon nitride, as evidenced by the removal rate of Polishing Composition 1B compared to the removal rate of Polishing Composition 1A. Similarly, Table 2 also shows that the addition of a non-ionic polymer, such as PEG300, PEG1000, PEG4000, and / or PEG8000, reduces the polishing removal rate of polysilicon while maintaining the removal rate of silicon oxide (i.e., TEOS) and silicon nitride, as evidenced by the removal rate of Polishing Composition 1C compared to the removal rate of Polishing Composition 1B.

[0175]

[0175] Furthermore, Table 2 shows that the polishing compositions 1D and 1E containing cationic surfactants and nonionic polymers are non-selective to TEOS, SiN, or polySi. In other words, the polishing compositions 1D and 1E showed approximately 1:1:1 removal rates of TEOS:SiN:PolySi. Therefore, the polishing compositions of the present invention containing cationic surfactants and nonionic polymers can be used to remove TEOS, SiN, or polySi at equal rates.

[0176] Example 3

[0176] This example demonstrates the beneficial polishing performance provided by polishing compositions containing cationic surfactants, nonionic polymers, and / or self-terminating agents prepared in accordance with the present invention.

[0177]

[0177] Patterned substrates containing TEOS, SiN, or polySi were polished using polishing compositions 1D and 1F-1O defined in Table 1 of Example 1 on a 300 mm AP-300™ (CTS Co., Ltd) polishing tool with Saesol C7 conditioner (Saesol Diamond Ind. Co., Ltd, South Korea) using the following parameters: 20.68 kPa (3 psi) down force, 250 ml / min slurry flow rate. The polishing time was 30 seconds. After polishing, the RR of TEOS, SiN, and polySi was measured, and the results are shown in Table 3. TIFF2025505182000006.tif183170

[0178]

[0178] As described in Example 2 above, Polishing Composition 1D was non-selective to TEOS, SiN, or polySi, and exhibited a removal rate of approximately 1:1:1 for TEOS:SiN:PolySi. As shown by the results of inventive Polishing Compositions 1F-1O in Table 3, the introduction of additional components into non-selective Polishing Composition 1D can improve the selectivity to TEOS, SiN, or polySi.

[0179] As can be seen from Table 3, inventive polishing compositions 1F-1H containing additional cationic polymer (i.e., polyDADMAC) selectively reduced the removal rate of silicon oxide (i.e., TEOS) from greater than 1500 Å / min to less than 350 Å / min while maintaining relatively consistent removal rates of SiN and PolySi. Similarly, inventive polishing compositions 1I and 1J show that polishing compositions containing higher molecular weight nonionic polymers (i.e., PEG8000) can selectively reduce the removal rate of polysilicon. Furthermore, inventive polishing compositions 1K-1O show that polishing compositions containing self-terminating agents (i.e., SHA or BHA) and / or cationic surfactants can reduce the removal rates of SiN and TEOS, respectively. Thus, the inventive compositions provided herein can be modified to transition from non-selective compositions (e.g., polishing composition 1D) to selective polishing compositions by adding cationic surfactants, nonionic polymers, and / or self-terminating agents.

[0180]

[0180] All references cited in this specification, including publications, patent applications, and patents, are incorporated by reference into this specification to the same extent as if each reference was individually and specifically indicated to be incorporated by reference and was set forth in its entirety in this specification.

[0181]

[0181] The use of "a" and "an" as well as "the" and "at least one" and similar referents in the context of describing the present invention (particularly in the context of the claims below) should be construed to encompass both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. When the term "at least one" is followed by a list of one or more items (e.g., "at least one of A and B"), it should be construed to mean one item selected from the listed items (A or B), or any combination of two or more of the listed items (A and B), unless otherwise indicated herein or clearly contradicted by context. The terms "comprising," "having," "including," and "containing" should be construed as open-ended terms (i.e., meaning "including, but not limited to"), unless otherwise indicated. The recitation of ranges of values ​​herein is merely intended to serve as a shorthand method of individually referring to each individual value within the range, unless otherwise indicated herein, and each individual value is incorporated herein as if it were individually set forth herein. All methods described herein can be performed in any suitable order, unless otherwise indicated herein or clearly contradicted by context. The use of any examples or illustrative language (e.g., "etc.") provided herein is merely intended to facilitate a better understanding of the invention, and does not impose limitations on the scope of the invention unless otherwise claimed. No language in this specification should be construed as indicating any non-claimed element as essential to the practice of the invention.

[0182]

[0182] Preferred embodiments of the present invention are described herein, including the best mode known to the inventors for carrying out the invention. Variations of these preferred embodiments will become apparent to those skilled in the art upon reading the foregoing description. The inventors expect that those skilled in the art will adopt such variations as necessary, and the inventors do not intend for the invention to be practiced otherwise than as specifically described herein. Accordingly, this invention includes all modifications and equivalents of the subject matter recited in the appended claims as permitted by applicable law. Moreover, combinations of the above-described elements in all possible variations thereof are encompassed by the present invention unless otherwise indicated herein or clearly contradicted by context.

Claims

1. (a) ceria abrasive particles; (b) cationic polymers, such as N-vinylimidazole, 2-(dimethylamino)ethyl acrylate ("DMAEA"), 2-(dimethylamino)ethyl methacrylate ("DMAEM"), 3-(dimethylamino)propyl methacrylamide ("DMAPMA"), 3-(dimethylamino)propyl acrylamide ("DMAPA"), 3-methacrylamidopropyl-trimethyl-ammonium chloride ("MAPTAC"), 3-acrylamidopropyl-trimethyl-ammonium chloride ("APTAC"), diallyldimethylammonium chloride ("DMTAC"), ... cationic polymers comprising a cationic monomer selected from N,N-dimethylaminoethyl acrylate benzyl chloride ("DMAEA.BCQ"), N,N-dimethylaminoethyl methacrylate benzyl chloride ("DMAEM.BCQ"), salts thereof, and combinations thereof; (c) a buffering agent, the buffering agent being a heterocyclic or heteroaromatic amine-based compound containing 1 to 5 nitrogen atoms; and (d) Water wherein the polishing composition has a pH of about 6 to about 9.

2. 10. The polishing composition of claim 1, wherein the polishing composition comprises from about 0.001% to about 10% by weight of ceria abrasive particles.

3. The polishing composition of claim 1 , wherein the polishing composition has a pH of about 7 to about 8.

4. 2. The polishing composition of claim 1, further comprising a nonionic polymer selected from polyalkylene glycols, polyether amines, polyethylene oxide / polypropylene oxide copolymers, polyacrylamides, polyvinylpyrrolidones, siloxane polyalkylene oxide copolymers, hydrophobically modified polyacrylate copolymers, hydrophilic nonionic polymers, polysaccharides, and combinations thereof.

5. The polishing composition of claim 1 , wherein the polishing composition further comprises a cationic surfactant.

6. 1. The polishing composition comprising a compound of formula (I):

2. The polishing composition of claim 1, further comprising a self-terminating agent of the formula: wherein R is selected from hydrogen, alkyl, heteroalkyl, cycloalkyl, heterocycloalkyl, aryl, and heteroaryl, each of which may be substituted or unsubstituted.

7. 10. The polishing composition of claim 1, wherein the polishing composition further comprises a conductivity modifier selected from ammonium salts, potassium salts, and combinations thereof.

8. 8. The polishing composition of claim 7, wherein the conductivity adjuster is selected from ammonium nitrate, ammonium chloride, ammonium bromide, ammonium acetate, potassium nitrate, potassium chloride, potassium bromide, potassium acetate, diallyldimethylammonium chloride, tetrabutylammonium bromide, tetramethylammonium bromide, tetraethylammonium bromide, benzyltrimethylammonium bromide, tetrabutylammonium chloride, tetramethylammonium chloride, tetraethylammonium chloride, benzyltrimethylammonium chloride, tetrabutylammonium acetate, tetramethylammonium acetate, tetraethylammonium acetate, benzyltrimethylammonium acetate, and combinations thereof.

9. 8. The polishing composition of claim 7, wherein the polishing composition has a conductivity of at least 170 μS / cm.

10. 8. The polishing composition of claim 7, wherein the polishing composition has a conductivity of at least 350 μS / cm.

11. 1. A method for chemically mechanically polishing a substrate, comprising: (i) providing a substrate; (ii) providing a polishing pad; (iii) (a) ceria abrasive particles; (b) cationic polymers, such as N-vinylimidazole, 2-(dimethylamino)ethyl acrylate ("DMAEA"), 2-(dimethylamino)ethyl methacrylate ("DMAEM"), 3-(dimethylamino)propyl methacrylamide ("DMAPMA"), 3-(dimethylamino)propyl acrylamide ("DMAPA"), 3-methacrylamidopropyl-trimethyl-ammonium chloride ("MAPTAC"), 3-acrylamidopropyl-trimethyl-ammonium chloride ("APTAC"), diallyldimethylammonium chloride ("DMTAC"), ... cationic polymers comprising a cationic monomer selected from N,N-dimethylaminoethyl acrylate benzyl chloride ("DMAEA.BCQ"), N,N-dimethylaminoethyl methacrylate benzyl chloride ("DMAEM.BCQ"), salts thereof, and combinations thereof; (c) a buffering agent, the buffering agent being a heterocyclic or heteroaromatic amine-based compound containing 1 to 5 nitrogen atoms; and (d) Water providing a chemical mechanical polishing composition comprising: (iv) contacting the substrate with the polishing pad and the chemical mechanical polishing composition; and (v) moving the polishing pad and the chemical-mechanical polishing composition relative to the substrate to abrade at least a portion of the substrate to polish the substrate.

12. The method of claim 11, wherein the polishing composition comprises from about 0.001% to about 10% by weight of ceria abrasive particles.

13. The method of claim 11, wherein the polishing composition has a pH of about 7 to about 8.

14. The method of claim 11 , wherein the polishing composition further comprises a conductivity modifier selected from ammonium salts, potassium salts, and combinations thereof.

15. 15. The method of claim 14, wherein the conductivity adjuster is selected from ammonium nitrate, ammonium chloride, ammonium bromide, ammonium acetate, potassium nitrate, potassium chloride, potassium bromide, potassium acetate, diallyldimethylammonium chloride, tetrabutylammonium bromide, tetramethylammonium bromide, tetraethylammonium bromide, benzyltrimethylammonium bromide, tetrabutylammonium chloride, tetramethylammonium chloride, tetraethylammonium chloride, benzyltrimethylammonium chloride, tetrabutylammonium acetate, tetramethylammonium acetate, tetraethylammonium acetate, benzyltrimethylammonium acetate, and combinations thereof.

16. 12. The method of claim 11 , wherein the substrate comprises silicon oxide, silicon nitride, and polysilicon, and at least a portion of the silicon oxide is polished at a silicon oxide removal rate, at least a portion of the silicon nitride is polished at a silicon nitride removal rate, and at least a portion of the polysilicon is polished at a polysilicon removal rate to polish the substrate.

17. 12. The method of claim 11, wherein the polishing composition further comprises a nonionic polymer selected from polyalkylene glycols, polyetheramines, polyethylene oxide / polypropylene oxide copolymers, polyacrylamides, polyvinylpyrrolidones, siloxane polyalkylene oxide copolymers, hydrophobically modified polyacrylate copolymers, hydrophilic nonionic polymers, polysaccharides, and combinations thereof.

18. The method of claim 11 , wherein the polishing composition further comprises a cationic surfactant.

19. 1. The polishing composition comprising a compound of formula (I):

12. The method of claim 11, further comprising a self-terminating agent of the formula: wherein R is selected from hydrogen, alkyl, heteroalkyl, cycloalkyl, heterocycloalkyl, aryl, and heteroaryl, each of which may be substituted or unsubstituted.

20. 19. The method of claim 18, wherein the cationic surfactant is selected from N,N,N',N',N'-pentamethyl-N-tallow alkyl-1,3-propanediammonium dichloride, (oxydi-2,1-ethanediyl)bis(coco alkyl)dimethyl ammonium dichloride, salts thereof, and combinations thereof.

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