Self-stopping polishing composition and method for high topological selectivity

Abstract

The present invention provides a chemical mechanical polishing composition comprising: (a) an abrasive selected from ceria abrasives, zirconia abrasives, and combinations thereof, (b) a self-terminating agent selected from compounds of formula (I), (c) optionally a nonionic polymer, (d) a cationic monomeric compound, and (e) water, wherein the polishing composition has a pH of about 5.5 to about 8. The present invention also provides a method of chemically mechanically polishing a substrate, particularly a substrate comprising silicon oxide and optionally polysilicon, using the composition.

Description

[Background technology]

[0001] In the fabrication of integrated circuits and other electronic devices, multiple layers consisting of conductive materials, semiconductive materials, and dielectric materials are deposited onto or removed from a substrate surface. As material layers are sequentially deposited onto and removed from the substrate, the top surface of the substrate may become non-planar and require planarization. Surface planarization, or surface "polishing," is the process of creating a generally uniform and flat surface by removing material from the substrate surface. Planarization is useful for removing undesirable surface topologies and surface defects, such as rough surfaces, aggregated material, crystal lattice damage, scratches, and contaminated layers or materials. Planarization is also useful for forming features on the substrate, which is done by removing excess deposited material used to fill features and to provide a uniform surface for subsequent levels of metallization and processing.

[0002] Compositions and methods for planarizing or polishing the surface of a substrate are well known to those skilled in the art. Chemical mechanical planarization, or chemical mechanical polishing (CMP), is a common technique used to planarize substrates. CMP utilizes a chemical composition known as a CMP composition, or more simply a polishing composition (also called a polishing slurry), for selective material removal from the substrate. The polishing composition is typically applied to the substrate by bringing the substrate surface into contact with a polishing pad (e.g., a polishing cloth or polishing disc) saturated with the polishing composition. Polishing of the substrate is further aided by the chemical activity of the polishing composition and / or the mechanical activity of abrasives suspended in the polishing composition or incorporated into a polishing pad (e.g., a fixed polishing pad).

[0003] As integrated circuits become smaller and the number of integrated circuits on a chip increases, it is necessary to adapt to the limited space available on a typical chip by positioning the components that form the circuits closer to each other. Effective isolation between circuits is crucial to ensure optimal semiconductor performance. To this end, the active regions of the integrated circuit are isolated by etching shallow trenches into the semiconductor substrate and filling them with insulating material. More specifically, shallow trench isolation (STI) is a process in which silicon nitride is formed on a silicon substrate, shallow trenches are formed via etching or photolithography, and the trenches are filled by depositing a dielectric layer. Because the depth of the trenches thus formed varies, it is typically necessary to ensure complete filling of all trenches by depositing an excess of dielectric material on the upper surface of the substrate. The dielectric material (e.g., silicon oxide) is located on the underside and matches the topography of the substrate.

[0004] Thus, after the dielectric material is laid, the surface of the deposited dielectric material is characterized by a combination of raised areas of the dielectric material separated by trenches within the dielectric material. The raised areas and trenches of the dielectric material correspond to the corresponding raised areas and trenches on the lower surface. The region of the substrate surface containing the raised dielectric material and trenches is called the pattern field of the substrate, e.g., “pattern material,” “pattern oxide,” or “pattern dielectric.” The pattern field is characterized by “step height,” which is the difference in height of the raised areas of the dielectric material relative to the trench height.

[0005] Excess dielectric material is typically removed by the CMP process. The CMP process additionally provides a flat surface for further processing. During the removal of material from the raised areas, a predetermined amount of material is also removed from the trenches. This removal of material from the trenches is called "trench erosion" or "trench loss." Trench loss is the amount (thickness (e.g., angstroms (Å))) of material removed from the trenches in achieving planarization of the pattern dielectric material by eliminating the initial steps. Trench loss is calculated as the initial trench thickness minus the final trench thickness. Ideally, the rate of material removal from the trenches should be well below the rate of removal from the raised areas. Thus, as the material from the raised areas is removed (at a higher rate than the material removed from the trenches), the pattern dielectric becomes a highly planar surface. Such a surface is sometimes called a "blanket" region of the processed substrate surface, e.g., "blanket dielectric" or "blanket oxide."

[0006] Polishing compositions can be characterized according to their polishing rate (i.e., removal rate) and their planarization efficiency. Polishing rate refers to the rate at which material is removed from the surface of the substrate and is usually expressed in units of length (thickness (e.g., angstroms (Å))) per unit of time (per minute). Different removal rates for different substrate regions or for different stages of the polishing process may be important in evaluating process performance. "Pattern removal rate" or "active removal rate" is the rate at which dielectric material is removed from raised areas of the pattern dielectric layer during process stages where the substrate exhibits significant steps. "Blanket removal rate" refers to the rate at which dielectric material is removed from the planarized (i.e., "blanket") area of ​​the pattern dielectric layer at the end of a polishing process where the steps are significantly reduced (e.g., essentially entirely). Planarization efficiency is related to the step reduction (i.e., step reduction divided by trench loss) relative to the amount of material removed from the substrate. Specifically, a polishing surface, such as a polishing pad, must first come into contact with the surface's "high point" and then remove material to form a flat surface. As a result, a process that obtains a flat surface with less material removal is considered more efficient than a process that requires the removal of more material to achieve flatness.

[0007] In many cases, the removal rate of silicon oxide pattern material can be the rate-limiting step in the dielectric polishing process in the STI process; therefore, a high removal rate of the silicon oxide pattern is desired to increase device throughput. However, if the blanket removal rate is too fast, it can lead to trench erosion as a result of overpolishing the oxide in the exposed trenches, increasing the device defect rate. Reducing the blanket removal rate can avoid overpolishing and associated trench loss.

[0008] In certain applications, it is desirable for the CMP composition to exhibit "self-stopping" behavior, such that the removal rate decreases when the majority of the surface's "high points" (i.e., raised areas) have been removed. In self-stopping polishing applications, the removal rate is effectively high while significant steps exist on the substrate surface, and then decreases as the surface becomes effectively flat. In various dielectric polishing processes (e.g., STI processes), the removal rate of pattern dielectric material (e.g., dielectric layer) is typically the rate-limiting factor for the entire process. Therefore, a high removal rate of the pattern dielectric material is desired to increase throughput. Good efficiency in the form of relatively low trench loss is also desirable. Furthermore, if the dielectric removal rate remains high after planarization is achieved, overpolishing occurs, resulting in additional trench loss.

[0009] Therefore, there is still a need for self-stopping CMP compositions and methods for chemical mechanical polishing that can exhibit "self-stopping" behavior such that the removal rate decreases when a large portion of the surface's "high points" (i.e., raised areas) has been removed, and that can remain stable when exposed to polishing conditions.

[0010] The present invention provides such polishing compositions and methods. These and other advantages of the present invention, as well as additional features of the present invention, will become apparent from the description of the present invention provided herein. [Overview of the Initiative] [Means for solving the problem]

[0011] The present invention relates to a chemical mechanical polishing composition comprising (a) an abrasive selected from ceria abrasives, zirconia abrasives, and combinations thereof, and (b) formula (I): [ka] A self-stopping agent selected from the compounds of formula (I), wherein R is selected from the group consisting of hydrogen, alkyl, cycloalkyl, aryl, heterocyclic alkyl, and heterocyclic aryl, each of which may be substituted or unsubstituted, a cationic monomer compound, and water, and consisting essentially of or consisting of these components, and having a pH of about 5.5 to about 8, provides a chemical mechanical polishing composition.

[0012] The present invention is a method for chemically mechanically polishing a substrate, comprising: (i) preparing a substrate; (ii) preparing a polishing pad; (iii) preparing a polishing composition comprising (a) an abrasive selected from ceria abrasives, zirconia abrasives, and combinations thereof, (b) a self-stopping agent selected from the compounds of formula (I):

Chemical formula

Embodiments for Carrying Out the Invention

[0013] The present invention relates to a chemical mechanical polishing composition comprising: (a) an abrasive selected from ceria abrasives, zirconia abrasives, and combinations thereof, and (b) a compound of formula (I):

Chemical formula

[0014] The chemical mechanical polishing composition of the present invention contains an abrasive. It is desirable that the abrasive of the polishing composition is suitable for polishing the non-metallic parts of the substrate (pattern dielectric material, blanket dielectric material, pattern oxide material, blanket oxide material, etc.). Suitable abrasives include ceria abrasives (e.g., CeO2), zirconia abrasives (e.g., ZrO2), and combinations thereof.

[0015] Ceria abrasives and zirconia abrasives are well-known in the field of CMP technology and are commercially available. Examples of suitable ceria abrasives include, among others, wet process ceria, calcined ceria, and metal-doped type ceria. Suitable zirconia abrasives include, among others, metal-doped type zirconia and non-metal-doped type zirconia. Metal-doped type zirconia includes zirconia doped with cerium, calcium, magnesium, or yttrium, and the dopant element weight percentage is preferably 0.1% to 25%.

[0016] In some embodiments, the chemical mechanical polishing composition includes a ceria abrasive. As used herein, the term “ceria abrasive” can be interchangeably used with “ceria abrasive particles,” “ceria particles,” or “abrasive.” As is well known, ceria is an oxide of the rare earth metal cerium and is also known as ceric oxide, cerium oxide (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, for example, Ce2O3. Ceria abrasive particles may contain one or more of these oxides or other oxides of ceria.

[0017] The ceria abrasive particles may be of any suitable type. In one embodiment, the ceria abrasive particles include, essentially consist of, or comprise calcined ceria particles, wet ceria particles, wet-process ceria particles, or a combination thereof. Ceria abrasives suitable for use in the polishing compositions of the present invention, and processes for preparing them, are described in U.S. Patent Application No. 14 / 639,564, filed March 5, 2015, now U.S. Patent No. 9,505,952, entitled “Polishing Composition Containing Ceria Abrasive”, and U.S. Patent Application No. 15 / 207,973, filed July 12, 2016, entitled “Methods and Compositions for Processing Dielectric Substrate”, published U.S. Patent Application Publication No. 2017 / 0014969. These disclosures are incorporated herein by reference.

[0018] In preferred embodiments, the ceria polishing particles include wet ceria particles or wet-process ceria particles. As used herein, “wet ceria particles” or “wet-process ceria particles” (collectively referred to here as “wet-process” ceria particles) means ceria prepared by precipitation, condensation polymerization, or similar processes (unlike fumed or exothermic ceria). Polishing compositions of the present invention containing wet-process ceria particles have been shown to exhibit lower defect rates when used to polish substrates according to the methods of the present invention. While we do not wish to be bound by any particular theory, wet-process ceria includes nearly spherical ceria particles and / or smaller aggregated ceria particles, which, when used in the methods of the present invention, results in lower substrate defect rates. Examples of wet-process ceria include HC30® and HC60® ceria, commercially available from Rhodia, and Hybrid-30, commercially available from ANP Co., Ltd.

[0019] Ceria abrasives can be formed by any appropriate process. For example, the ceria abrasive may be a wet-process ceria particle formed according to the following process. Typically, the first step in synthesizing the wet-process ceria particle is to dissolve a ceria precursor in water. The ceria precursor may be any appropriate ceria precursor and may have any appropriate charge, for example, Ce 3+ or Ce 4+ It may contain a ceria salt having [a specific characteristic]. Suitable ceria precursors include, for example, cerium III nitrate, cerium IV ammonium nitrate, cerium III carbonate, cerium IV sulfate, and cerium III chloride. Preferably, the ceria precursor is cerium III nitrate.

[0020] The pH of the ceria precursor solution is typically raised to form amorphous Ce(OH)3. The pH of the solution can be raised to any appropriate pH. For example, the pH of the solution can be raised to about 10 or higher, about 10.5 or higher, about 11 or higher, or about 12 or higher. Typically, the solution will have a pH of about 14 or lower, for example, about 13.5 or lower, or about 13 or lower. The pH of the solution can be raised using any appropriate base. Appropriate bases include, for example, KOH, NaOH, NH4OH, and tetramethylammonium hydroxide. Organic bases, such as ethanolamine and diethanolamine, are also suitable. As the pH increases, the solution becomes cloudy and turns white, and amorphous Ce(OH)3 is formed.

[0021] The ceria precursor is typically mixed over several hours. For example, the solution can be mixed for approximately 1 hour or more, e.g., approximately 2 hours or more, approximately 4 hours or more, approximately 6 hours or more, approximately 8 hours or more, approximately 12 hours or more, approximately 16 hours or more, approximately 20 hours or more, or approximately 24 hours or more. Typically, the solution is mixed for approximately 1 to 24 hours, e.g., approximately 2 hours, e.g., approximately 8 hours, or e.g., approximately 12 hours. Once mixing is complete, the solution can be transferred to a pressurized container and heated.

[0022] The ceria precursor solution can be heated to any appropriate temperature. For example, the solution can be heated to temperatures of approximately 50°C or higher, approximately 75°C or higher, approximately 100°C or higher, approximately 125°C or higher, approximately 150°C or higher, approximately 175°C or higher, and approximately 200°C or higher. Alternatively or in addition to the above, the solution can be heated to temperatures of approximately 500°C or lower, approximately 450°C or lower, approximately 400°C or lower, approximately 375°C or lower, approximately 350°C or lower, approximately 300°C or lower, approximately 250°C or lower, approximately 225°C or lower, or approximately 200°C or lower. Thus, the solution can be heated to temperatures within a range defined by any two of the above endpoints. For example, the solution can be heated to temperatures ranging from approximately 50°C to 300°C, such as approximately 50°C to 275°C, approximately 50°C to 250°C, approximately 50°C to 200°C, approximately 75°C to 300°C, approximately 75°C to 250°C, approximately 75°C to 200°C, approximately 100°C to 300°C, approximately 100°C to 250°C, or approximately 100°C to 225°C.

[0023] The ceria precursor solution is typically heated over several hours. For example, the solution can be heated for about 1 hour or more, e.g., about 5 hours or more, about 10 hours or more, about 25 hours or more, about 50 hours or more, about 75 hours or more, about 100 hours or more, or about 110 hours or more. Alternatively or in addition to this, the solution can be heated for about 200 hours or less, e.g., about 180 hours or less, about 165 hours or less, about 150 hours or less, about 125 hours or less, about 115 hours or less, or about 100 hours or less. Thus, the solution can be heated over a period of time divided by any two of the above endpoints. For example, the solution can be heated from about 1 hour to about 150 hours, e.g., about 5 hours to about 130 hours, about 10 hours to about 120 hours, about 15 hours to about 115 hours, or about 25 hours to about 100 hours.

[0024] After heating, the precipitated ceria particles can be separated by filtering the ceria precursor solution. Unreacted ceria precursors can be removed by rinsing the precipitant with excess water. The mixture of the precipitant and excess water can be filtered, followed by each rinsing step to remove impurities. After thorough rinsing, the ceria particles can be dried for additional processing, such as sintering, or the ceria particles can be directly redispersed.

[0025] Ceria particles can optionally be dried and sintered before redispersion. The terms “sintering” and “calcination” are used interchangeably herein to mean heating of ceria particles under the conditions described below. Sintering of ceria particles affects the resulting degree of crystallinity. While we do not wish to be bound by any particular theory, it is believed that sintering ceria particles at high temperatures and for extended periods reduces defects in the crystal lattice structure of the particles. Ceria particles can be sintered using any appropriate method. For example, ceria particles can be dried and then sintered at a high temperature. Drying can be carried out at room temperature or at a high temperature. Specifically, drying can be carried out at temperatures of about 20°C to about 40°C, e.g., about 25°C, about 30°C, or about 35°C. Alternatively or in addition to this, drying can also be carried out at high temperatures of about 80°C to about 150°C, e.g., about 85°C, about 100°C, about 115°C, about 125°C, or about 140°C. After drying the ceria particles, a powder can be formed by grinding these ceria particles. Grinding can be carried out using any suitable grinding material, such as zirconia.

[0026] Ceria particles can be sintered in any suitable furnace at any suitable temperature. For example, ceria particles can be sintered at temperatures of approximately 200°C or higher, such as approximately 215°C or higher, approximately 225°C or higher, approximately 250°C or higher, approximately 275°C or higher, approximately 300°C or higher, approximately 350°C or higher, or approximately 375°C or higher. Alternatively, or in addition to the above, ceria particles can be sintered at temperatures of approximately 1000°C or lower, such as approximately 900°C or lower, approximately 750°C or lower, approximately 650°C or lower, approximately 550°C or lower, approximately 500°C or lower, approximately 450°C or lower, or approximately 400°C or lower. Thus, ceria particles can be sintered at temperatures delimited by any two of the above endpoints. For example, ceria particles can be sintered at temperatures ranging from approximately 200°C to 1000°C, such as approximately 250°C to 800°C, approximately 300°C to 700°C, approximately 325°C to 650°C, approximately 350°C to 600°C, approximately 350°C to 550°C, approximately 400°C to 550°C, approximately 450°C to 800°C, approximately 500°C to 1000°C, or approximately 500°C to 800°C.

[0027] Ceria particles can be sintered for any appropriate length of time. For example, ceria particles can be sintered for about 1 hour or more, for example, about 2 hours or more, about 5 hours or more, or about 8 hours or more. Alternatively, or in addition to this, ceria particles can be sintered for about 20 hours or less, for example, about 18 hours or less, about 15 hours or less, about 12 hours or less, or about 10 hours or less. Thus, ceria particles can be sintered for a time period defined by any two of the above endpoints. For example, ceria particles can be sintered for about 1 hour to about 20 hours, for example, about 1 hour to about 15 hours, about 1 hour to about 10 hours, about 1 hour to about 5 hours, about 5 hours to about 20 hours, or about 10 hours to about 20 hours.

[0028] Ceria particles can also be sintered at various temperatures and for various durations within the above range. For example, ceria particles can be sintered in a zone furnace, which exposes the ceria particles to one or more temperatures over various durations. For example, ceria particles can be sintered at a temperature of approximately 200°C to approximately 1000°C for approximately one hour or more, and then sintered at different temperatures within the range of approximately 200°C to approximately 1000°C for approximately one hour or more.

[0029] Ceria particles are typically redispersed in a suitable carrier, such as an aqueous carrier, specifically in water. If the ceria particles are sintered, they are redispersed after sintering is complete. Ceria particles can be redispersed using any suitable process. Typically, ceria particles are redispersed by lowering the pH of the mixture of ceria particles and water using a suitable acid. As the pH is lowered, the surface of the ceria particles generates a positive zeta potential. This positive zeta potential forms a repulsive force between the ceria particles, which facilitates the redispersion of the ceria particles. The pH of the mixture can be lowered using any suitable acid. Suitable acids include, for example, hydrochloric acid and nitric acid. Organic acids that are highly water-soluble and have hydrophilic functional groups are also suitable. Suitable organic acids include, for example, acetic acid. Acids with polyvalent anions, such as H3PO4 and H2SO4, are generally undesirable. The pH of the mixture can be lowered to any suitable pH. For example, the pH of a mixture can be lowered to approximately 2 to 5, such as approximately 2.5, 3, 3.5, 4, or 4.5. Typically, the pH of a mixture is not lowered to below approximately 2.

[0030] Acid-dispersed ceria particles are typically milled to reduce their particle size. Preferably, the ceria particles are milled simultaneously with redispersion. Milling can be carried out using a suitable milling material, such as zirconia. Milling can also be carried out using sonication or wet-jet treatment. After milling, the ceria particles can be filtered to remove any remaining large particles. For example, the ceria particles can be filtered using a filter with a pore size of about 0.3 μm or larger, for example, about 0.4 μm or larger, or about 0.5 μm or larger.

[0031] Ceria abrasives can have any appropriate average particle size (i.e., average particle diameter). If the average ceria abrasive particle size is too small, the polishing composition may not exhibit a sufficient removal rate. Conversely, if the average ceria abrasive particle size is too large, the polishing composition may exhibit undesirable polishing performance, such as a poor substrate defect rate. Therefore, ceria abrasive particles can have an average particle size of about 10 nm or more, for example, 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 in addition to this, ceria abrasive particles can have an average particle size of about 1,000 nm or less, for example, 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, ceria abrasive particles can have an average particle size separated by any two of the above endpoints. For example, ceria abrasive particles can have an average particle size of approximately 10 nm to 1,000 nm, such as approximately 10 nm to 750 nm, approximately 15 nm to 500 nm, approximately 20 nm to 250 nm, approximately 20 nm to 150 nm, approximately 25 nm to 150 nm, approximately 25 nm to 100 nm, approximately 50 nm to 150 nm, or approximately 50 nm to 100 nm. In the case of spherical ceria abrasive particles, the particle size is the diameter of the particle. In the case of non-spherical ceria abrasive particles, the particle size is the diameter of the smallest sphere surrounding the particle. The particle size of ceria abrasive particles can be measured using any appropriate technique, for example, laser diffraction. Suitable particle size measuring instruments are available, for example, from Malvern Instruments (Malvern, UK).

[0032] In some embodiments, the ceria abrasive particles of the polishing composition exhibit a multimodal particle size distribution. The term “multimodal” as used herein means that the ceria abrasive particles exhibit an average particle size distribution having at least two maximum values ​​(e.g., two or more maximum values, three or more maximum values, four or more maximum values, or five or more maximum values). 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 maximum values. The terms “maximum” and “maxima” mean peaks in the particle size distribution. The peaks correspond to the average particle size described with respect to the ceria abrasive particles. Thus, for example, a plot of the number of particles against particle size reflects a bimodal particle size distribution, in which case the first peak is in the particle size range of approximately 75 nm to 150 nm, for example, approximately 80 nm to 140 nm, approximately 85 nm to 130 nm, or approximately 90 nm to 120 nm, and the second peak is in the particle size range of approximately 25 nm to 70 nm, for example, approximately 30 nm to 65 nm, approximately 35 nm to 65 nm, or approximately 40 nm to 60 nm. Ceria abrasive particles having a multimodal particle size distribution can be obtained by combining two different types of ceria abrasive particles, each having a unimodal particle size distribution.

[0033] The ceria abrasive particles are preferably colloidally stable in the polishing composition of the present invention. The term colloid means a suspension of ceria abrasive particles in an aqueous carrier (e.g., water). Colloidal stability means maintaining its suspension over time. In the context of the present invention, when the abrasive is placed in a 100 mL graduated cylinder and left standing without stirring for 2 hours, the abrasive is considered colloidally stable if the difference between the particle concentration in the bottom 50 mL of the graduated cylinder ([B] (as g / mL)) and the particle concentration in the top 50 mL of the graduated cylinder ([T] (as g / mL)) is divided by the initial concentration of particles in the abrasive composition, and the result 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.

[0034] The polishing composition may contain any appropriate amount of abrasive (e.g., ceria abrasive, zirconia abrasive, or a combination thereof). If the polishing composition of the present invention contains too little abrasive, the composition may not exhibit sufficient removal rate. Conversely, if the polishing composition contains too much abrasive, the polishing composition may exhibit undesirable polishing performance and / or may be cost-inefficient and / or lack stability. The polishing composition contains about 10 wt% or less of abrasive (e.g., ceria abrasive, zirconia abrasive, or a combination thereof), for example, about 9 wt% or less, about 8 wt% or less, about 7 wt% or less, about 6 wt% or less, about 5 wt% or less, about 4 wt% or less, about 3 wt% or less, about 2 wt% or less, about 1 wt% or less, about 0.9 wt% or less, about 0.8 wt% or less, about 0.7 wt% or less, about 0.6 wt% or less, or about 0.5 wt.% or less. Alternatively, or in addition to the above, the polishing composition may contain about 0.001 wt% or more of an abrasive (e.g., ceria abrasive, zirconia abrasive, or a combination thereof), for example, about 0.005 wt% or more, about 0.01 wt% or more, about 0.05 wt% or more, or about 0.1 wt% or more. Thus, the abrasive (e.g., ceria abrasive, zirconia abrasive, or a combination thereof) may be present in the polishing composition in an amount separated by any two of the above endpoints. For example, a polishing composition may contain about 0.001 wt% to about 10 wt.%, for example, about 0.001 wt% to about 9 wt.%, about 0.005 wt% to about 8 wt%, about 0.01 wt% to about 7 wt%, about 0.05 wt% to about 6 wt%, about 0.1 wt% to about 5 wt%, about 0.5 wt% to about 5 wt%, about 0.5 wt% to about 4 wt%, about 1 wt% to about 3 wt%, or about 1.5 wt% to about 2.5 wt% of abrasives (e.g., ceria abrasives, zirconia abrasives, or a combination thereof) at the point of use.In another embodiment, the polishing composition is a concentrate and contains about 1 to 3 wt% (e.g., about 1.2 wt% or about 1.6 wt%) of an abrasive (e.g., a ceria abrasive, a zirconia abrasive, or a combination thereof).

[0035] The polishing composition contains a self-stopping agent. The self-stopping agent can be any suitable compound that can reduce the removal rate of one or more of silicon oxide and polysilicon. In some embodiments, the self-stopping agent has the formula (I):

Chemical formula

[0036] As used herein, the term "alkyl" refers to a straight-chain or branched, saturated or unsaturated aliphatic radical having the indicated number of carbon atoms. Alkyl can have any number of carbons, e.g., C 1-2 、C 1-3 、C 1-4 [[ID=2l]]、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 <000002l>can be included. For example, C 1-6Examples of alkyl groups include methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl, tert-butyl, pentyl, isopentyl, and hexyl. Alkyl can also refer to alkyl groups with up to 30 carbon atoms, such as heptyl, octyl, nonyl, and decyl. 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, amide, acyl, nitro, cyano, and alkoxy groups.

[0037] As used herein, the term "heteroalkyl" means an alkyl group as described herein, wherein one or more carbon atoms are optionally and independently substituted with heteroatoms selected from N, O, and S.

[0038] As used herein, the term "cycloalkyl" means a saturated or partially unsaturated, monocyclic, fusion bicyclic, or bridging polycyclic ring assembly with 3 to 12 or the number of atoms indicated. A cycloalkyl group can have any number of carbon atoms, for example, 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 3-12This may include saturated monocyclic carbocyclic groups, such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, and cyclooctyl. Saturated bicyclic and polycyclic carbocyclic groups include, for example, norbornane, [2.2.2]bicyclooctane, decahydronaphthalene, and adamantane. The carbocyclic group may be partially unsaturated and may have one or more double or triple bonds within the ring. Examples of typical partially unsaturated carbocyclic groups include 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.

[0039] As used herein, the term "heterocycloalkyl" means a cycloalkyl group as described herein, wherein one or more carbon atoms are optionally and independently substituted with heteroatoms selected from N, O, and S.

[0040] As used herein, the term “aryl” means an aromatic ring system having any appropriate number of ring atoms and any appropriate number of rings. An aryl group may have any appropriate number of ring atoms, e.g., 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, or 16 ring atoms, and 6-10, 6-12, or 6-14 ring members. An aryl group may be monocyclic, or it may fuse to form a bicyclic or tricyclic group, or it may be linked by a bond to form a biaryl group. Representative aryl groups include phenyl, naphthyl, and biphenyl. Other aryl groups include benzyl and have a methylene bond. Some aryl groups have 6-12 ring members, e.g., phenyl, naphthyl, or biphenyl. Other aryl groups have 6-10 ring members, e.g., phenyl or naphthyl.

[0041] As used herein, the term "heteroaryl" means an aryl group as described herein, wherein one or more carbon atoms are optionally and independently substituted with heteroatoms selected from N, O, and S.

[0042] In certain embodiments, the self-deactivating agent is selected from hydroxamic acid, acetohydroxamic acid, benzhydroxamic acid (benzohydroxamic acid), salicylic acid, and combinations thereof.

[0043] The polishing composition may contain any appropriate amount of self-stopping agent. The polishing composition may contain about 10 ppm or more of self-stopping agent, 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. Alternatively or in addition to this, the polishing composition may contain about 5000 ppm or less of self-stopping agent, for example, about 3000 ppm or less, about 1000 ppm or less, 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. Thus, the polishing composition may contain self-stopping agent in amounts separated by any two of the above endpoints. For example, a polishing composition may contain an auto-stopping agent in an amount of approximately 10 ppm to 5000 ppm, such as approximately 10 ppm to 3000 ppm, approximately 10 ppm to 1000 ppm, approximately 10 ppm to 800 ppm, approximately 10 ppm to 600 ppm, approximately 10 ppm to 400 ppm, approximately 10 ppm to 200 ppm, approximately 10 ppm to 100 ppm, approximately 25 ppm to 5000 ppm, approximately 25 ppm to 3000 ppm, approximately 25 ppm to 1000 ppm, approximately 25 ppm to 800 ppm, approximately 25 ppm to 600 ppm, approximately 25 ppm to 400 ppm, approximately 25 ppm to 200 ppm, or approximately 25 ppm to 100 ppm.

[0044] While we do not wish to be bound by any particular theory, self-stopping agents are thought to facilitate a nonlinear response to a given down force (DF) on tetraethoxysilane (TEOS) blanket dielectric material. During polishing, the pattern dielectric material is subjected to a higher effective down force (DF) than that of the blanket dielectric material because contact is limited to only a few portions of the pattern dielectric material that are in contact with the pad. A higher effective DF applied to the TEOS pattern dielectric material results in a "high" removal rate (e.g., pattern removal rate) polishing regime with a TEOS removal rate of approximately 8,000 Å / min. A lower effective DF results in a "stopped" polishing regime (e.g., blanket removal rate) with a TEOS removal rate of approximately 1,000 Å / min or less. The difference between the "high" regime and the "stopped" regime is typically clear, with either a "high" or "stopped" removal rate being observed for a given DF. Therefore, even when the added DF is determined to be in a "stopped" regime by the blanket wafer, the self-stopping agent is thought to enable a "high" removal rate (i.e., pattern removal rate) in a desirable manner.

[0045] Furthermore, it is noteworthy that this mechanism does not depend solely on DF. This is because the trench oxide removal rate on patterned dielectric materials is higher than the blanket removal rate, even though the effective DF in the trenches is lower than on blanket wafers. For example, in some polishing applications, the concentration of the self-stopping agent is involved in the observed effect. This is because, at low concentrations, the self-stopping agent can act as a speed enhancer (e.g., a "high" removal rate is observed), and at higher concentrations, self-stopping agent behavior is observed (e.g., a "stopped" removal rate is observed). Thus, some speed enhancers can have a dual effect. For example, if the polishing composition contains picolinic acid at a lower concentration, picolinic acid can function as a speed enhancer. However, if the polishing composition contains picolinic acid at a higher concentration, picolinic acid can function as a self-stopping agent. Typically, picolinic acid functions as a speed enhancer at concentrations of less than about 1000 ppm by weight (e.g., about 500 ppm, about 250 ppm, etc.).

[0046] The chemical machinery polishing composition contains a cationic monomer compound. The cationic monomer compound may be any suitable cationic (e.g., ammonium) compound recognized by those skilled in the art that can be polymerized (e.g., through radical polymerization, addition polymerization, metathesis polymerization, or similar methods). For example, cationic monomer compounds include 2-(dimethylamino)ethyl acrylate ("DMAEA"), 2-(dimethylamino)ethyl methacrylate ("DMAEM"), 3-(dimethylamino)propyl methacrylamide ("DMAPMA"), 3-(dimethylamino)propyl acrylamide ("DMAPA"), 3-methacrylamidepropyl-trimethyl-ammonium chloride ("MAPTAC"), 3-acrylamidepropyl-trimethyl-ammonium chloride ("APTAC"), diallyl dimethyl This may include ammonium chloride ("DADMAC"), 2-(acryloyloxy)-N,N,N-trimethylethaneaminium chloride ("DMAEA.MCQ"), 2-(methacryloyloxy)-N,N,N-trimethylethaneaminium chloride ("DMAEM.MCQ"), N,N-dimethylaminoethyl acrylate benzyl chloride ("DMAEA.BCQ"), N,N-dimethylaminoethyl methacrylate benzyl chloride ("DMAEM.BCQ"), salts thereof, and combinations thereof. In certain embodiments, the cationic monomer compound is selected from diallyldimethylammonium chloride ("DADMAC"), 2-(acryloyloxy)-N,N,N-trimethylethaneaminium chloride ("DMAEA.MCQ"), 2-(methacryloyloxy)-N,N,N-trimethylethaneaminium chloride ("DMAEM.MCQ"), salts thereof, and combinations thereof. In preferred embodiments, the cationic monomer compound is diallyldimethylammonium chloride ("DADMAC") or a salt thereof.

[0047] The polishing composition may contain any appropriate amount of cationic monomer compound. The polishing composition may contain about 10 ppm or more, 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 monomer compound. Alternatively or in addition to this, the polishing composition may contain about 1000 ppm or less, 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 monomer compound. Thus, the polishing composition may contain cationic monomer compound within a range delimited by any two of the above endpoints. For example, a polishing composition may contain cationic monomer compounds in concentrations of approximately 10 ppm to 1000 ppm, such as approximately 10 ppm to 800 ppm, approximately 10 ppm to 600 ppm, approximately 10 ppm to 400 ppm, approximately 10 ppm to 200 ppm, approximately 10 ppm to 100 ppm, approximately 25 ppm to 1000 ppm, approximately 25 ppm to 800 ppm, approximately 25 ppm to 600 ppm, approximately 25 ppm to 400 ppm, approximately 25 ppm to 200 ppm, or approximately 25 ppm to 100 ppm.

[0048] In some embodiments, the polishing composition further comprises a nonionic polymer. Thus, in some aspects, the present invention is a chemical mechanical polishing composition comprising (a) an abrasive selected from ceria abrasives, zirconia abrasives, and combinations thereof, and (b) formula (I): [ka] The present invention provides a chemical mechanical polishing composition comprising (c) a self-stopping agent selected from the compounds, wherein R is selected from the group consisting of hydrogen, alkyl, cycloalkyl, aryl, heterocyclic alkyl, and heterocyclic aryl, each of which may be substituted or unsubstituted; (c) a nonionic polymer; (d) a cationic monomer compound; and (e) water, which are essentially composed of these, or composed of these, wherein the pH of the polishing composition is about 5.5 to about 8.

[0049] The nonionic polymer may be any suitable polymer having no cationic or anionic charge and a pH of about 5.5 to about 8. In some embodiments, the nonionic polymer is selected from polyalkylene glycols, polyetheramines, polyethylene oxide / polypropylene oxide copolymers, polyacrylamides, polyvinylpyrrolidone, siloxane polyalkylene oxide copolymers, hydrophobic modified polyacrylate copolymers, hydrophilic nonionic polymers, polysaccharides, and combinations thereof. In certain embodiments, the nonionic polymer is polyvinylpyrrolidone, polyalkylene glycol (e.g., polyethylene glycol (PEG) or polypropylene oxide (PPO)), polyethylene oxide / polypropylene oxide copolymer, or a combination thereof. In preferred embodiments, the nonionic polymer is polyethylene glycol (PEG).

[0050] Nonionic polymers can have any appropriate weight-average molecular weight. The weight-average molecular weight of a nonionic polymer may be 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 1,000 g / mol or more, about 1,500 g / mol or more, about 2,000 g / mol or more, about 2,500 g / mol or more, about 3,000 g / mol or more, about 3,500 g / mol or more, about 4,000 g / mol or more, about 4,500 g / mol or more, about 5,000 g / mol or more, about 5,500 g / mol or more, about 6,000 g / mol or more, about 6,500 g / mol or more, about 7,000 g / mol or more, or about 7,500 g / mol or more. Alternatively, or in addition to the above, the weight-average molecular weight of the nonionic polymer may be about 20,000 g / mol or less, for example, about 10,000 g / mol or less, 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 may have a weight-average molecular weight separated by any two of the above endpoints. For example, the weight-average molecular weight of nonionic polymers ranges from approximately 400 g / mol to approximately 20,000 g / mol, for example, approximately 400 g / mol to approximately 10,000 g / mol, approximately 400 g / mol to approximately 9,000 g / mol, approximately 400 g / mol to approximately 8,000 g / mol, approximately 400 g / mol to approximately 7,000 g / mol, approximately 400 g / mol to approximately 6,000 g / mol, and approximately 400 g / mol to approximately 5,000 g / mol. g / mol, approximately 1,000 g / mol to approximately 20,000 g / mol, approximately 1,000 g / mol to approximately 10,000 g / mol, approximately 1,000 g / mol to approximately 9,000 g / mol, approximately 1,000 g / mol to approximately 8,000 g / mol, approximately 1,000 g / mol to approximately 7,000 g / mol, approximately 1,000 g / mol to approximately 6,000 g / mol, or approximately 1,000 g / mol to approximately 5,000 g / mol potential.

[0051] The polishing composition may contain any appropriate amount of nonionic polymer, if present. The polishing composition may contain about 25 ppm or more of nonionic polymer, for example, about 50 ppm or more, about 100 ppm or more, or about 200 ppm or more. Alternatively or in addition to this, the polishing composition may contain about 5000 ppm or less of nonionic polymer, for example, 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 may contain nonionic polymer in an amount separated by any two of the above endpoints. For example, the polishing composition may contain nonionic polymers in concentrations of approximately 25 ppm to 5000 ppm, such as approximately 25 ppm to 400 ppm, approximately 25 ppm to 3000 ppm, approximately 25 ppm to 2000 ppm, approximately 25 ppm to 1000 ppm, approximately 50 ppm to 5000 ppm, approximately 50 ppm to 4000 ppm, approximately 50 ppm to 3000 ppm, approximately 50 ppm to 2000 ppm, approximately 50 ppm to 1000 ppm, approximately 100 ppm to 5000 ppm, or approximately 100 ppm to 1000 ppm.

[0052] The polishing composition contains an aqueous carrier. The aqueous carrier contains water (e.g., deionized water) and may contain one or more water-miscible organic solvents. Examples of organic solvents that may be used include alcohols, such as propenyl alcohol, isopropyl alcohol, ethanol, 1-propanol, methanol, 1-hexanol, and similar substances; aldehydes, such as acetylaldehyde, and similar substances; ketones, such as acetone, diacetone alcohol, methyl ethyl ketone, and similar substances; esters, such as ethyl formate, propyl formate, ethyl acetate, methyl acetate, methyl lactate, butyl lactate, ethyl lactate, and similar substances; ethers and amides, such as N,N-dimethylformamide, dimethylimidazolidinone, N-methylpyrrolidone, and similar substances; polyhydric alcohols and derivatives of polyhydric alcohols, such as ethylene glycol, glycerol, diethylene glycol, diethylene glycol monomethyl ether, and similar substances; and nitrogen-containing organic compounds, such as acetonitrile, amylamine, isopropylamine, imidazole, dimethylamine, and similar substances. Preferably, the aqueous carrier is water alone, i.e., water without the presence of any organic solvent.

[0053] A chemical mechanical polishing composition may contain one or more compounds (i.e., pH-adjusting compounds) that can (i.e., adjust) the pH of the polishing composition. The pH of the polishing composition can be adjusted using any suitable compound that can adjust the pH of the polishing composition. It is desirable that the pH-adjusting compound is water-soluble and compatible with the other components of the polishing composition. Typically, the pH of a chemical mechanical polishing composition is about 5.5 to about 8 at the point of use (e.g., about 5.5 to about 7.5, about 5.5 to about 7, about 5.5 to about 6.5, about 5.5 to about 6, about 6 to about 8, about 6 to about 7.5, about 6 to about 7, about 6 to about 6.5, about 7 to about 8, or about 7 to about 7.5). In certain embodiments, the pH of the chemical mechanical polishing composition is about 5.5 to about 7 at the point of use. Preferably, the pH of the chemical mechanical polishing composition is about 6 to about 6.5 at the point of use.

[0054] Compounds capable of adjusting and buffering pH can be selected from alkylamines, ammonium salts, alkali metal salts, carboxylic acids, alkali metal hydroxides, alkali metal nitrates, alkali metal carbonates, alkali metal bicarbonates, borates, and mixtures thereof.

[0055] Chemical mechanical polishing compositions optionally further include one or more additives. Examples of additives include conditioners, acids (e.g., sulfonic acid), complexing agents, chelating agents, biocides, scale inhibitors, and dispersants.

[0056] The biocide may be any suitable biocide, if present, and may be present in any suitable amount in the polishing composition. A preferred biocide is 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.

[0057] Polishing compositions can be manufactured by any appropriate technique, much of which is known to those skilled in the art. Polishing compositions can be prepared by batch or continuous processes. Broadly speaking, polishing compositions are prepared by combining the components of a polishing composition. As used herein, the term “component” includes individual components (e.g., abrasives, self-stopping agents, cationic monomer compounds, any nonionic polymers, and / or any other additives), as well as any combination of components (e.g., abrasives, self-stopping agents, cationic monomer compounds, any nonionic polymers, and / or any other additives).

[0058] For example, a polishing composition can be prepared by (i) providing all or part of a liquid carrier, (ii) dispersing an abrasive, a self-stopping agent, a cationic monomer compound, any nonionic polymer, and / or any other additive using any means suitable for preparing the dispersion, (iii) adjusting the pH of the dispersion as necessary, and (iv) optionally adding appropriate amounts of any other components and / or additives to the mixture.

[0059] Alternatively, or in addition to the above, a polishing composition may also be prepared by (i) preparing one or more components in an abrasive slurry (e.g., a self-stopping agent, a cationic monomer compound, any nonionic polymer, and / or any other additive), (ii) preparing one or more components in an additive solution (e.g., a self-stopping agent, a cationic monomer compound, any nonionic polymer, and / or any other additive), (iii) combining the abrasive slurry and the additive solution to form a mixture, (iv) optionally adding an appropriate amount of any other additive to the mixture, and (v) adjusting the pH of the mixture as necessary.

[0060] The polishing composition can be supplied as a one-package system comprising an abrasive, a self-stopping agent, a cationic monomer compound, an optional nonionic polymer, any other optional additive, and water. Alternatively, the polishing composition of the present invention can also be supplied as a two-package system comprising an abrasive slurry in a first package and an additive solution in a second package. The abrasive slurry essentially consists of abrasive particles and water, or consists of these, and the additive solution essentially consists of a self-stopping agent, a cationic monomer compound, an optional nonionic polymer, and / or any other optional additive. The two-package system allows for adjustment of the polishing composition properties by changing the blending ratio of the two packages, namely the abrasive slurry and the additive solution.

[0061] Such a two-package polishing system can be utilized by employing various methods. For example, the abrasive slurry and additive solution can be delivered to the polishing table by various pipes joined and connected to the outlet of the supply piping. The abrasive slurry and additive solution can be mixed immediately before or just before polishing, or they can be supplied onto the polishing table simultaneously. Furthermore, when mixing the two packages, the polishing composition and the resulting substrate polishing properties can be adjusted by adding deionized water if desired.

[0062] Similarly, a system consisting of 3, 4, or 5 or more packages can be used in connection with the present invention. Each of the multiple containers contains one or more of the different components of the chemical mechanical polishing composition of the present invention, one or more arbitrary components, and / or the same component in different concentrations.

[0063] For the purpose of mixing components contained in two or three storage devices for the purpose of manufacturing a polishing composition at or near the point of use, the storage devices typically include one or more flow lines extending from each storage device to the point of use of the polishing composition (e.g., a platen, polishing pad, or substrate surface). As used herein, the term “point of use” means the point at which the polishing composition is applied to the substrate surface (e.g., the polishing pad or the substrate surface itself). “Flow line” means the flow path from an individual storage container to the point of use of the components stored in the storage container. Each flow line may extend directly to the point of use, or two or more flow lines may be combined at any point to form a single flow line leading to the point of use. Furthermore, any of the flow lines (e.g., individual flow lines or combined flow lines) may first extend to one or more other devices (e.g., pumping devices, measuring devices, mixing devices, etc.) before reaching the point of use of the components.

[0064] The components of the polishing composition can be delivered independently to the point of use (for example, components are delivered to the substrate surface and then mixed during the polishing process), or one or more components can be combined, for example, immediately before or just before delivery to the point of use. Components are combined "just before delivery to the point of use" if they are combined approximately 5 minutes or more before being added to the platen in a mixed form, for example approximately 4 minutes, 3 minutes, 2 minutes, 1 minute, 45 seconds, 30 seconds, or 10 seconds before being added to the platen in a mixed form, or simultaneously with the delivery of components at the point of use (components are combined by a dispenser). Components are also combined "just before delivery to the point of use" if they are combined within 5 m of the point of use, for example within 1 m of the point of use, or within 10 cm of the point of use (for example within 1 cm of the point of use).

[0065] When two or more components of the polishing composition are combined before reaching the point of use, the components can be combined in a flow line and delivered to the point of use without using a mixing device. Alternatively, one or more of the flow lines may extend into a mixing device to facilitate the combination of two or more components. Any suitable mixing device can be used. For example, the mixing device may be a nozzle or jet (e.g., a high-pressure nozzle or jet) through which two or more components flow. Alternatively, the mixing device may be a container-type mixing device including one or more inlets through which two or more components of the polishing slurry are introduced into the mixer, and at least one outlet through which the mixed components pass as they leave the mixer to be delivered directly or via other elements of the device (e.g., via one or more flow lines) to the point of use. Furthermore, the mixing device may include two or more chambers, each having at least one inlet and at least one outlet, through which two or more components are combined in each chamber. When a container-type mixing device is used, the mixing device preferably includes a mixing mechanism to further facilitate the combination of components. Mixing mechanisms are generally known in the art and include stirrers, blenders, agitators, paddle-shaped baffles, gas sparger systems, vibrators, and the like.

[0066] The polishing composition may also be provided as a concentrate. The concentrate is intended to be diluted with an appropriate amount of water before use. In such embodiments, the polishing composition concentrate contains the components of the polishing composition in such amounts that, when the concentrate is diluted with an appropriate amount of water, each component of the polishing composition will be present in the polishing composition in amounts within the appropriate range described above with respect to each component. For example, abrasives, self-stoppers, cationic monomer compounds, any nonionic polymers, and / or any other additives may each be present in the concentrate in amounts about twice (e.g., about three times, about four times, or about five times) higher than the concentrations described above with respect to each component, so when the concentrate is diluted with equal volumes of water (e.g., two equal volumes of water, three equal volumes of water, or four equal volumes of water, respectively), each component will be present in the polishing composition in amounts within the appropriate range described above with respect to each component. Furthermore, as will be understood by those skilled in the art, the concentrate may, by containing an appropriate portion of the water present in the final polishing composition, ensure that the abrasive particles, self-stopping agents, cationic monomer compounds, any nonionic polymers, and / or any other additives are at least partially or completely dissolved in the concentrate.

[0067] The present invention relates to a method for chemically and mechanically polishing a substrate, comprising: (i) preparing a substrate; (ii) preparing a polishing pad; and (iii) (a) an abrasive selected from ceria abrasive, zirconia abrasive, and combinations thereof, and (b) formula (I): [ka] Further, a method for chemically and mechanically polishing a substrate is provided, comprising: (c) a self-stopping agent selected from compounds such as (i) a self-stopping agent in which R is selected from the group consisting of hydrogen, alkyl, cycloalkyl, aryl, heterocyclic alkyl, and heterocyclic aryl, each of which may be substituted or unsubstituted; (c) optionally a nonionic polymer; (d) a cationic monomer compound; and (e) water, wherein the pH of the polishing composition is about 5.5 to about 8; (iv) bringing the substrate into contact with the polishing pad and the chemically and mechanically polishing composition; and (v) polishing at least a portion of the substrate by moving the polishing pad and the chemically and mechanically polishing composition against the substrate, thereby polishing the substrate.

[0068] Chemical mechanical polishing compositions can be used to polish any suitable substrate and are particularly useful for polishing substrates comprising at least one layer (typically a surface layer) made of a low dielectric material. Suitable substrates include wafers used in the semiconductor industry. Wafers typically contain or consist of metals, metal oxides, metal nitrides, metal composites, metal alloys, or combinations thereof. The methods of the present invention are particularly useful for polishing substrates comprising silicon oxide and / or polysilicon, for example, one or all of the materials described above. In some embodiments, the substrate comprises silicon oxide and polysilicon on the surface of the substrate, and the substrate is polished by polishing at least a portion of the silicon oxide and polysilicon on the surface of the substrate.

[0069] In certain embodiments, the substrate comprises silicon oxide and polysilicon. The polysilicon can be any suitable polysilicon. Many of these polysilicones are known in the art. The polysilicon can have any suitable phase and can be amorphous, crystalline, or a combination thereof. The silicon oxide can similarly be any suitable silicon oxide. Many of these silicon oxides are known in the art. Examples of preferred types of silicon oxide include borosilicate glass (BPSG), high-density plasma (HDP) oxides and / or plasma-assisted tetraethyl orthosilicate (PETEOS) and / or tetraethyl orthosilicate (TEOS), thermal oxides, and undoped silicate glasses.

[0070] By tailoring the chemical mechanical polishing composition of the present invention, effective polishing is possible within a selective, desired polishing range for specific thin-layer materials, while minimizing the removal of surface imperfections, defects, corrosion, erosion, and stop layers. The selectivity can be controlled by changing the relative concentrations of the components of the polishing composition. As used herein, the term "selectivity" refers to the removal rate ratio of two different target materials. For example, selectivity can refer to the removal rate ratio of two different materials, or the removal rate ratio of two different topographies (e.g., blanket removal versus active removal).

[0071] Preferably, the chemical mechanical polishing composition of the present invention can provide an active silicon oxide removal rate of at least 8,000 Å / min, for example, at least 9,000 Å / min, at least 10,000 Å / min, at least 11,000 Å / min, or at least 12,000 Å / min. Alternatively or in addition to this, the chemical mechanical polishing composition of the present invention can provide a selectivity ratio of at least 20:1, for example, at least 25:1, at least 30:1, at least 35:1, or at least 40:1 between the active silicon oxide removal rate and the blanket silicon oxide removal rate. In a particular embodiment, the chemical mechanical polishing composition of the present invention provides an active silicon oxide removal rate of at least 11,000 Å / min, and a selectivity ratio of at least 25:1 between the active silicon oxide removal rate and the blanket silicon oxide removal rate. In a preferred embodiment, the chemical mechanical polishing composition of the present invention provides an active silicon dioxide removal rate of at least 12,000 Å / min, and a selectivity ratio of at least 30:1 between the active silicon dioxide removal rate and the blanket silicon dioxide removal rate.

[0072] Similarly, in a particular embodiment, the present invention relates to a method for chemically and mechanically polishing a substrate, comprising: (i) preparing a substrate; (ii) preparing a polishing pad; (iii) (a) an abrasive selected from ceria abrasives, zirconia abrasives, and combinations thereof; and (b) formula (I): [ka] Further, a method for chemically and mechanically polishing a substrate is provided, comprising: (c) a self-stopping agent selected from compounds such as (i) a self-stopping agent in which R is selected from the group consisting of hydrogen, alkyl, cycloalkyl, aryl, heterocyclic alkyl, and heterocyclic aryl, each of which may be substituted or unsubstituted; (c) a nonionic polymer; (d) a cationic monomer compound; and (e) water, wherein the pH of the polishing composition is about 5.5 to about 8; (iv) bringing the substrate into contact with the polishing pad and the chemically and mechanically polishing composition; and (v) polishing at least a portion of the substrate by moving the polishing pad and the chemically and mechanically polishing composition against the substrate, thereby polishing the substrate.

[0073] Preferably, the chemical mechanical polishing composition of the present invention enables selective chemical mechanical polishing of a substrate containing silicon oxide and polysilicon in order to selectively remove silicon oxide from polysilicon at an increased rate. In this regard, the method can remove silicon oxide from polysilicon with a selectivity ratio greater than about 20:1, as determined by angstroms removed per minute. In some embodiments, the method can remove silicon oxide from polysilicon with a selectivity ratio greater than about 40:1, as determined by angstroms removed per minute. In some embodiments, the method can remove silicon oxide from polysilicon with a selectivity ratio greater than about 80:1, as determined by angstroms removed per minute.

[0074] While I don't want to be bound by any specific theory, it is thought that adding a nonionic polymer can selectively reduce the removal rate of polysilicon, thereby increasing the selectivity ratio for removing silicon dioxide relative to polysilicon. In other words, while a nonionic polymer can reduce the removal rate of polysilicon, it has little to no effect on the removal rate of silicon dioxide.

[0075] Broadly speaking, the chemical mechanical polishing compositions of the present invention are stable when exposed to a polishing process, as evidenced by the increase in abrasive particle size during polishing. For example, in some embodiments, the average abrasive particle size (i.e., average particle diameter) after polishing is less than 100% of the increase compared to the average abrasive particle size (i.e., average particle diameter) before polishing. In certain embodiments, the average abrasive particle size (i.e., average particle diameter) after polishing is less than 50% of the increase compared to the average abrasive particle size (i.e., average particle diameter) before polishing. In preferred embodiments, the average abrasive particle size (i.e., average particle diameter) after polishing is less than 20% of the increase compared to the average abrasive particle size (i.e., average particle diameter) before polishing.

[0076] While we do not wish to be bound by any specific theory, it is believed that using cationic monomer compounds instead of cationic polymers and / or using a lower pH (e.g., about 6 to about 6.5) may result in a more stable polishing composition. As demonstrated by Example 4 provided herein, a polishing composition containing a cationic polymer and pH 7.8 at the point of use may result in a particle size increase of more than 400% from before polishing to after polishing.

[0077] The polishing composition of the present invention preferably exhibits low particle defects when polishing a substrate, as determined by appropriate techniques. In preferred embodiments, the chemical mechanical polishing composition of the present invention includes a wet process ceria, which contributes to the low defect rate. Particle defects on a substrate polished with the polishing composition of the present invention can be determined by any appropriate technique. For example, laser light scattering techniques, such as dark-field vertical beam composites (DCN) and dark-field oblique beam composites (DCO), can be used to determine particle defects on a polished substrate. Suitable instruments for evaluating particle defects are available, for example, from KLA-Tencor (e.g., SURFSCAN® SPI instruments operating at 120 nm or 160 nm thresholds).

[0078] A substrate polished with the polishing composition of the present invention, particularly silicon containing silicon oxide and / or polysilicon, preferably has a DCN value of about 20,000 counts or less, for example, 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, the DCN value of a substrate polished according to an embodiment of the present invention is about 750 counts or less, for example, about 500 counts or less, about 250 counts or less, about 125 counts or less, or about 100 counts or less. Alternatively or in addition thereto, a substrate polished with the chemical mechanical polishing composition of the present invention preferably exhibits low scratching as determined by appropriate technique. For example, a silicon wafer polished according to an embodiment of the present invention preferably has about 250 scratches or less, or about 125 scratches or less, as determined by any appropriate method known in the art.

[0079] The chemical mechanical polishing composition and method of the present invention are particularly suitable for use in conjunction with a chemical mechanical polishing apparatus. Typically, the apparatus includes a platen which is in motion during use and has a velocity resulting from orbital motion, linear motion, or circular motion; a polishing pad which is in contact with the platen and moves together with the platen during motion; and a carrier which holds a substrate to be polished by bringing the substrate into contact with the surface of the polishing pad and moving the substrate. Polishing of the substrate is performed by bringing the substrate into contact with the polishing pad and the polishing composition of the present invention, and then moving the polishing pad relative to the substrate, thereby polishing at least a portion of the substrate and polishing the substrate.

[0080] A substrate can be polished with a chemical mechanical polishing composition using any suitable polishing pad (e.g., a polishing surface). Suitable polishing pads include, for example, woven and nonwoven polishing pads. Furthermore, suitable polishing pads may include any suitable polymer having various densities, hardness, thickness, compressibility, rebound capacity under compression, and compression coefficient. Suitable polymers include, for example, polyvinyl chloride, polyvinyl fluoride, nylon, fluorocarbon, polycarbonate, polyester, polyacrylate, polyether, polyethylene, polyamide, polyurethane, polystyrene, polypropylene, their co-formed products, and mixtures thereof. A flexible polyurethane polishing pad is particularly useful in connection with the polishing method of the present invention. Typical pad examples include SURFIN® 000, SURFIN® SSW1, SPM3100 (Eminess Technologies), POLITEX®, commercially available from Dow Chemical Company (Newark, Delaware), POLYPAS® 27, commercially available from Fujibo (Osaka, Japan), and EPIC® D100 pads or NEXPLANAR® E6088, commercially available from Cabot Microelectronics (Aurora, Illinois). A preferred polishing pad is the rigid microporous polyurethane pad (IC1010®), commercially available from Dow Chemical.

[0081] Preferably, the chemical mechanical polishing apparatus further includes an on-site polishing endpoint detection system. Many such systems are known in the art. Techniques for inspecting and monitoring the polishing process by analyzing light or other radiation reflected from the surface of a substrate are known in the art. Such methods are described, for example, in U.S. Patent 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. Preferably, by inspecting or monitoring the progress of the polishing process with respect to the substrate being polished, it becomes possible to determine the polishing endpoint, i.e., when the polishing process for a particular substrate should be terminated.

[0082] Embodiment (1) Embodiment (1) is a chemical mechanical polishing composition, (a) Abrasives selected from ceria abrasives, zirconia abrasives, and combinations thereof, (b) Formula (I): [ka] A self-deactivating agent selected from the compounds, R is a self-terminating agent selected from the group consisting of hydrogen, alkyl, cycloalkyl, aryl, heterocyclic alkyl, and heterocyclic aryl, each of which may be substituted or unsubstituted. (c) Cationic monomer compounds and (d) Water and Includes, The pH of the polishing composition is approximately 5.5 to approximately 8. A chemical mechanical polishing composition is presented.

[0083] (2) Embodiment (2) presents the polishing composition of Embodiment (1), wherein the polishing composition contains about 0.001 wt% to about 10 wt% of an abrasive.

[0084] (3) Embodiment (3) presents a polishing composition of Embodiment (1) or Embodiment (2) in which the polishing composition contains about 0.05 wt% to about 5 wt% of an abrasive.

[0085] (4) Embodiment (4) presents one of the polishing compositions of Embodiments (1) to (3), wherein the abrasive is a ceria abrasive.

[0086] (5) Embodiment (5) presents one of the polishing compositions of Embodiments (1) to (3), wherein the abrasive is a zirconia abrasive.

[0087] (6) Embodiment (6) presents one of the polishing compositions from Embodiments (1) to (5), wherein the pH of the polishing composition is approximately 5.5 to approximately 7.

[0088] (7) Embodiment (7) presents one of the polishing compositions of Embodiments (1) to (6), wherein the pH of the polishing composition is approximately 6 to approximately 6.5.

[0089] (8) Embodiment (8) presents one polishing composition from Embodiments (1) to (7), wherein the self-stopping agent is selected from hydroxamic acid, acetohydroxamic acid, benzhydroxamic acid, salicylic acid, and combinations thereof.

[0090] (9) Embodiment (9) presents one of the polishing compositions of Embodiments (1) to (8), wherein the self-stopping agent is hydroxamic acid.

[0091] (10) Embodiment (10) presents any one of the polishing compositions of Embodiments (1) to (8), wherein the self-detergent is benzhydroxamic acid.

[0092] (11) Embodiment (11) presents one of the polishing compositions of Embodiments (1) to (8), wherein the self-determinating agent is salicylhydroxamic acid.

[0093] (12) Embodiment (12) presents any one of the polishing compositions of Embodiments (1) to (11), wherein the chemical mechanical polishing composition further comprises a nonionic polymer.

[0094] (13) Embodiment (13) presents a polishing composition of Embodiment (12) in which the nonionic polymer is selected from polyalkylene glycol, polyetheramine, polyethylene oxide / polypropylene oxide copolymer, polyacrylamide, polyvinylpyrrolidone, siloxane polyalkylene oxide copolymer, hydrophobic modified polyacrylate copolymer, hydrophilic nonionic polymer, polysaccharides, and combinations thereof.

[0095] (14) Embodiment (14) presents the polishing composition of Embodiment (12) or Embodiment (13), wherein the nonionic polymer is polyvinylpyrrolidone.

[0096] (15) Embodiment (15) presents a polishing composition of Embodiment (12) or Embodiment (13) in which the nonionic polymer is polyalkylene glycol.

[0097] (16) Embodiment (16) presents a polishing composition of Embodiment (12) or Embodiment (13), wherein the nonionic polymer is a polyethylene oxide / polypropylene oxide copolymer.

[0098] (17) In embodiment (17), the cationic monomer compound is 2-(dimethylamino)ethyl acrylate ("DMAEA"), 2-(dimethylamino)ethyl methacrylate ("DMAEM"), 3-(dimethylamino)propyl methacrylamide ("DMAPMA"), 3-(dimethylamino)propyl acrylamide ("DMAPA"), 3-methacrylamidepropyl-trimethyl-ammonium chloride ("MAPTAC"), 3-acrylamidepropyl-trimethyl-ammonium chloride ("APTAC"), diallyldimethylammonium chloride ("D A polishing composition is presented which is selected from ADMAC"), 2-(acryloyloxy)-N,N,N-trimethylethaneaminium chloride ("DMAEA.MCQ"), 2-(methacryloyloxy)-N,N,N-trimethylethaneaminium chloride ("DMAEM.MCQ"), N,N-dimethylaminoethyl acrylate benzyl chloride ("DMAEA.BCQ"), N,N-dimethylaminoethyl methacrylate benzyl chloride ("DMAEM.BCQ"), salts thereof, and combinations thereof, one of any one of embodiments (1) to (16).

[0099] (18) Embodiment (18) presents any one of the polishing compositions of Embodiments (1) to (17), wherein the cationic monomer compound is diallyldimethylammonium chloride ("DADMAC") or a salt thereof.

[0100] (19) Embodiment (19) is a method for chemically and mechanically polishing a substrate, (i) Prepare the circuit board, (ii) Prepare a polishing pad, (iii) (a) Abrasives selected from ceria abrasives, zirconia abrasives, and combinations thereof, (b) Formula (I): [ka] A self-deactivating agent selected from the compounds, R is a self-terminating agent selected from the group consisting of hydrogen, alkyl, cycloalkyl, aryl, heterocyclic alkyl, and heterocyclic aryl, each of which may be substituted or unsubstituted. (c) Cationic monomer compounds and (d) Water and Includes, The pH of the polishing composition is approximately 5.5 to approximately 8. Prepare a chemical mechanical polishing composition, (iv) The substrate is brought into contact with the polishing pad and the chemical mechanical polishing composition, and (v) Polishing the substrate by moving the polishing pad and the chemical mechanical polishing composition over the substrate, thereby polishing the substrate. A method for chemically and mechanically polishing a substrate is presented, which includes the following.

[0101] (20) Embodiment (20) presents the polishing composition of Embodiment (19), wherein the polishing composition contains about 0.001 wt% to about 10 wt% of an abrasive.

[0102] (21) Embodiment (21) presents a polishing composition of Embodiment (19) or Embodiment (20) wherein the polishing composition contains about 0.05 wt% to about 5 wt% of an abrasive.

[0103] (22) Embodiment (22) presents any one of embodiments (19) to (21) of polishing composition, wherein the abrasive is a ceria abrasive.

[0104] (23) Embodiment (23) presents any one of embodiments (19) to (21) in which the abrasive is a zirconia abrasive.

[0105] (24) Embodiment (24) presents one of the polishing compositions of Embodiments (19) to (23), wherein the pH of the polishing composition is approximately 5.5 to approximately 7.

[0106] (25) Embodiment (25) presents one of the polishing compositions of Embodiments (19) to (24), wherein the pH of the polishing composition is approximately 6 to approximately 6.5.

[0107] (26) Embodiment (26) presents one of the polishing compositions of Embodiments (19) to (25), wherein the self-stopping agent is selected from hydroxamic acid, acetohydroxamic acid, benzhydroxamic acid, salicylic acid, and combinations thereof.

[0108] (27) Embodiment (27) presents any one of the polishing compositions of Embodiments (19) to (26), wherein the self-detergent is hydroxamic acid.

[0109] (28) Embodiment (28) presents any one of the polishing compositions of Embodiments (19) to (26), wherein the self-detergent is benzhydroxamic acid.

[0110] (29) Embodiment (29) presents any one of the polishing compositions of Embodiments (19) to (26), wherein the self-determinating agent is salicylohydroxamic acid.

[0111] (30) Embodiment (30) presents any one of the polishing compositions of Embodiments (19) to (29), wherein the chemical mechanical polishing composition further comprises a nonionic polymer.

[0112] (31) Embodiment (31) presents the method of Embodiment (30) in which the nonionic polymer is selected from polyalkylene glycol, polyetheramine, polyethylene oxide / polypropylene oxide copolymer, polyacrylamide, polyvinylpyrrolidone, siloxane polyalkylene oxide copolymer, hydrophobic modified polyacrylate copolymer, hydrophilic nonionic polymer, polysaccharides, and combinations thereof.

[0113] (32) Embodiment (32) presents the method of Embodiment (30) or Embodiment (31) in which the nonionic polymer is polyvinylpyrrolidone.

[0114] (33) Embodiment (33) presents the method of Embodiment (30) or Embodiment (31) in which the nonionic polymer is polyalkylene glycol.

[0115] (34) Embodiment (34) presents the method of Embodiment (30) or Embodiment (31) in which the nonionic polymer is a polyethylene oxide / polypropylene oxide copolymer.

[0116] (35) In embodiment (35), the cationic monomer compound is 2-(dimethylamino)ethyl acrylate ("DMAEA"), 2-(dimethylamino)ethyl methacrylate ("DMAEM"), 3-(dimethylamino)propyl methacrylamide ("DMAPMA"), 3-(dimethylamino)propyl acrylamide ("DMAPA"), 3-methacrylamidepropyl-trimethyl-ammonium chloride ("MAPTAC"), 3-acrylamidopropyl-trimethyl-ammonium chloride ("APTAC"), diallyldimethylammonium chloride One of the embodiments (19) to (34) is presented, selected from ("DADMAC"), 2-(acryloyloxy)-N,N,N-trimethylethaneaminium chloride ("DMAEA.MCQ"), 2-(methacryloyloxy)-N,N,N-trimethylethaneaminium chloride ("DMAEM.MCQ"), N,N-dimethylaminoethyl acrylate benzyl chloride ("DMAEA.BCQ"), N,N-dimethylaminoethyl methacrylate benzyl chloride ("DMAEM.BCQ"), salts thereof, and combinations thereof.

[0117] (36) Embodiment (36) presents one of the methods of Embodiments (19) to (35), wherein the cationic monomer compound is diallyldimethylammonium chloride ("DADMAC") or a salt thereof.

[0118] (37) Embodiment (37) presents one of the embodiments (19) to (36) wherein the substrate contains silicon dioxide, and the substrate is polished by polishing at least a portion of the silicon dioxide.

[0119] (38) Embodiment (38) presents the method of Embodiment (37) wherein the substrate contains polysilicon, and the substrate is polished by polishing at least a portion of the polysilicon.

[0120] (39) Embodiment (39) presents the method of Embodiment (38) in which silicon oxide is removed from polysilicon with a selectivity ratio of more than approximately 20:1, determined by the angstroms removed per minute by polishing the substrate.

[0121] (40) Embodiment (40) presents the method of Embodiment (39) in which silicon oxide is removed from polysilicon with a selectivity ratio of more than approximately 40:1, determined by the angstroms removed per minute by polishing the substrate.

[0122] Examples These embodiments described below further illustrate the present invention, but they should of course not be interpreted as limiting the scope of the present invention in any way.

[0123] The following abbreviations, namely removal rate (RR), tetraethyl orthosilicate (TEOS), polysilicon (polySi), polyethylene glycol (PEG), point of use (POU), and weight-average molecular weight (MW), are used throughout the examples.

[0124] In the following examples, a substrate TEOS (i.e., silicon dioxide) and / or polySi was applied to a patterned wafer, and the substrate was 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 IC 1010® polishing pad (Rohm and Haas Electronic Materials) or a NEXPLANAR® E6088 polishing pad (Cabot Microelectronics, Aurora, Illinois) was used for all compositions with the same polishing parameters. Unless otherwise specified, the standard REFLEXION® polishing parameters are as follows: IC1010® pad, downforce = 20.68 kPa (3 psi), head speed = 110 rpm, platen speed = 120 rpm, total flow rate = 200 mL / min. Unless otherwise specified, the standard AP-300® polishing parameters are as follows: IC1010® pad, downforce = 20.68 kPa (3 psi), head speed = 110 rpm, platen speed = 120 rpm, total flow rate = 200 mL / min. Unless otherwise specified, the standard MIRRA® polishing parameters are as follows: IC1010® pad, downforce = 20.68 kPa (3 psi), head speed = 110 rpm, platen speed = 120 rpm, total flow rate = 200 mL / min, or NEXPLANAR® E6088 pad, downforce = 20.68 kPa (3 psi), head speed = 110 rpm, platen speed = 120 rpm, total flow rate = 200 mL / min. Film thickness was measured using spectroscopic ellipsometry, and the removal rate was calculated by subtracting the final thickness from the initial thickness.

[0125] Example 1 This example clarifies the preparation of a polishing composition according to the present invention, comprising (a) a ceria abrasive, a zirconia abrasive, or a combination thereof, (b) a self-stopping agent, (c) optionally a nonionic polymer, and (d) a cationic monomer compound. The efficiency of the polishing method described in the claims was clarified by using polishing formulations A1 and A2 and additive formulations B1 to B13 when preparing the polishing compositions used in Examples 2 to 4 below.

[0126] For each of the polishing compositions used in Examples 2-4, polishing formulations A1 and A2 were prepared using either Hybrid-30 ceria particles (commercially available from ANP Co., Ltd.) or zirconium oxide (commercially available from Saint Gobain) in combination with picolinic acid (500 ppm). The pH of the resulting mixtures was adjusted to 4.2. The polishing formulations are summarized in Table 1. [Table 1]

[0127] For each of the polishing compositions used in Examples 2-4, diallyldimethylammonium chloride ("DADMAC") or poly(2-methacryloyloxyethyltrimethylammonium chloride "polyMADQUAT") is used as a cationic additive, benzhydroxamic acid or salicylohydroxamic acid is used as a self-stopping agent, and polyvinylpyrrolidone ("PVP"), Brij TM Additive formulations B1-B13 were prepared using S20 (commercially available from Sigma Aldrich) or Pluronic® L31 (commercially available from Sigma Aldrich) as nonionic polymers. The additive formulations were optionally further enriched with Bis-Tris® (commercially available from Sigma Aldrich) as a buffer, and the pH was adjusted with nitric acid or triethanolamine ("TEA"). The additive formulations are summarized in Table 2. [Table 2]

[0128] Example 2 This example reveals the beneficial topographic selectivity ratio provided by a polishing composition according to the present invention, which comprises (a) a ceria abrasive, a zirconia abrasive, or a combination thereof, (b) a self-stopping agent, (c) optionally a nonionic polymer, and (d) a cationic monomer compound.

[0129] A separate patterned wafer (200x300mm wafer) containing 250μm TEOS features (features approximately 20,000Å thick) with a 50% pattern density was coated onto a patterned silicon substrate with a step of approximately 8,000Å, and then polished on a Mirra® or Reflexion® tool using an IC1010® pad containing comparative polishing compositions 2A-2D and the polishing compositions 2E-2J of the present invention. Comparative polishing compositions 2A-2D and the polishing compositions 2E-2J of the present invention were prepared by combining 7:3 volume polishing formulations and additive formulations. The active removal rate (active RR) and blanket removal rate (blanket RR) were measured, and the results are shown in Table 3.

[0130] Comparative polishing compositions 2A to 2D differed from polishing compositions 2E to 2J of the present invention. This is because polishing compositions 2E to 2J of the present invention contained cationic monomer compounds. [Table 3]

[0131] As is clear from Table 3, comparative polishing composition 2A, which contains a ceria abrasive, a self-stopping agent (hydroxamic acid), and pH 4.2, exhibited a low active RR:blanket RR ratio. In other words, comparative polishing composition 2A, which does not contain a cationic monomer compound, exhibited a limited selectivity ratio between the active removal rate and the blanket removal rate.

[0132] Table 3 also shows that comparative polishing compositions 2B-2D, containing ceria abrasives, self-stopping agents, and cationic polymers, exhibited improved active RR:blanket RR ratios compared to comparative polishing composition 2A. However, the active removal rate was significantly reduced when the pH could not be raised to 7.7, as demonstrated by comparative polishing composition 2C (see comparative polishing compositions 2B and 2D).

[0133] In contrast, polishing compositions 2E to 2J of the present invention, containing a ceria abrasive, a self-stopping agent, and a cationic monomer compound, exhibited high active removal rates and high topographic selectivity at a low pH of 6.2. These results demonstrate the improved topographic selectivity exhibited by polishing compositions 2E to 2J of the present invention compared to comparative polishing compositions 2A to 2D.

[0134] Example 3 This example clarifies the effect on selectivity exhibited by the polishing composition of the present invention containing a nonionic polymer.

[0135] Patterned substrates containing TEOS and PolySi were polished on Mirra® or Reflexion® tools using IC1010® pads containing comparative polishing compositions 3A and 3B, and the polishing compositions 3C to 3K of the present invention. Comparative polishing compositions 3A and 3B, and the polishing compositions 3C to 3K of the present invention were prepared by combining 7:3 volume polishing compounds and additive compounds. The active removal rate (TEOS) and PolySi removal rate were measured, and the results are shown in Table 4.

[0136] Comparative polishing compositions 3A and 3B, and polishing composition 3C of the present invention, differ from polishing compositions 3D to 3K of the present invention. This is because polishing compositions 3D to 3K of the present invention contain nonionic polymers. [Table 4]

[0137] As is clear from Table 4, polishing compositions 3C to 3K of the present invention, which contain (a) ceria abrasive, zirconia abrasive, (b) self-stopping agent, and (c) cationic monomer compound, exhibited a higher active removal rate (i.e., TEOS removal rate) than comparative polishing composition 3A, which contains ceria abrasive, self-stopping agent, and cationic polymer at the same pH (i.e., pH 6.2). Polishing compositions 3H to 3K of the present invention were highly efficient, so their active removal rates (i.e., TEOS removal rates) were not measured.

[0138] Table 4 also lists nonionic polymers, such as polyvinylpyrrolidone ("PVP"), Brij TM The addition of S20 (commercially available from Sigma Aldrich) or Pluronic® L31 (commercially available from Sigma Aldrich) also significantly reduced the PolySi removal rate without affecting the active removal rate (i.e., TEOS removal rate), as demonstrated by polishing compositions 3D-3K of the present invention compared to comparative polishing compositions 3A and 3B or polishing composition 3C of the present invention. These results demonstrate that the polishing compositions according to the present invention have a high active removal rate (i.e., TEOS removal rate) and can be selectively polished to polish TEOS more effectively than PolySi by adding nonionic polymers without significantly reducing the TEOS removal rate.

[0139] Example 4 This example clarifies the effect on stability exhibited by the polishing composition of the present invention, which contains a cationic monomer compound, unlike a cationic polymer.

[0140] Patterned substrates containing TEOS and PolySi were polished on Mirra® or Reflexion® tools using IC1010® pads having comparative polishing composition 4A and the polishing compositions 4B and 4C of the present invention. Comparative polishing composition 4A and the polishing compositions 4B and 4C of the present invention were prepared by combining 7:3 volume of polishing compound and additive compound. The particle size of the abrasive particles before and after polishing was measured, and the results are shown in Table 5.

[0141] Comparative polishing composition 4A differed from polishing compositions 4B and 4C of the present invention because polishing compositions 4B and 4C contained cationic monomer compounds instead of cationic polymers and had a lower pH. Each polishing composition was used for 60 seconds of polishing. [Table 5]

[0142] As is clear from Table 5, polishing compositions 4B and 4C of the present invention, which contain diallyldimethylammonium chloride ("DADMAC") as a cationic monomer compound and have a pH of 6.2, maintained the same particle size before and after polishing. In contrast, comparative polishing composition 4A, which contains poly(2-methacryloyloxyethyltrimethylammonium chloride) ("polyMADQUAT") and has a pH of 7.8, exhibited a particle size increase of more than four times after polishing. These results demonstrate that polishing compositions containing cationic monomer compounds and lower pH (e.g., about 5.5 to about 7) are more stable than polishing compositions containing cationic polymers and higher pH (e.g., about 7.5 or higher).

[0143] All references, including publications, patent applications, and patent specifications, cited herein are incorporated by reference to the same extent as each reference is individually and specifically indicated and expressed herein as a whole.

[0144] In the context describing the present invention (particularly in the context of the claims below), the terms “a,” “an,” and “the,” and similar references, should be interpreted as covering both singular and plural forms unless otherwise indicated or unless the context clearly contradicts this. When a term is used that is followed by an enumeration of one or more items (e.g., at least one of A and B), this should be interpreted as meaning one item (A or B) selected from the listed items, or any combination of two or more items (A and B), unless otherwise indicated or unless the context clearly contradicts this. The terms “comprising,” “having,” “including,” and “containing” should be interpreted as open-ended terms (i.e., “including, but not limited to”) unless otherwise specified. The description of value ranges in this specification is intended solely as an abbreviation for individually referring to each distinct value within that range, unless otherwise indicated. Each distinct value is invoked herein as if it were individually described herein. All methods described herein may be performed in any appropriate order unless otherwise indicated herein or unless it would be clearly inconsistent with the context. Any examples or illustrative language provided herein (e.g., "such as") are intended solely to better illustrate the invention and, unless otherwise asserted, do not limit the scope of the invention. No language in this specification should be construed as suggesting any element not present in the claims that is essential for the practice of the invention.

[0145] Preferred embodiments of the present invention are described herein, including the best modes known to the inventors for carrying out the invention. Modifications of these preferred embodiments may be apparent to those skilled in the art by reading the foregoing description. The inventors anticipate that those skilled in the art will adopt such modifications as appropriate, and the inventors intend that the invention may be carried out in ways different from those specifically described herein. Accordingly, the invention includes all modifications and equivalents of the subject matter listed in the claims herein, as permitted by applicable law. Furthermore, any combination of the above elements in any possible modification is encompassed by the invention unless otherwise indicated herein or unless it would be clearly inconsistent with the context. The following embodiments can be cited as examples of the present invention. (Note 1) A chemical mechanical polishing composition, (a) Abrasives selected from ceria abrasives, zirconia abrasives, and combinations thereof, (b) Formula (I): [ka] A self-deactivating agent selected from the compounds, R is a self-terminating agent selected from the group consisting of hydrogen, alkyl, cycloalkyl, aryl, heterocyclic alkyl, and heterocyclic aryl, each of which may be substituted or unsubstituted. (c) Cationic monomer compounds and (d) Water and Includes, The pH of the polishing composition is approximately 5.5 to approximately 8. Chemical mechanical polishing composition. (Note 2) The polishing composition according to Appendix 1, wherein the polishing composition contains about 0.001 wt% to about 10 wt% of an abrasive. (Note 3) The polishing composition according to Appendix 1, wherein the polishing composition contains about 0.05 wt% to about 5 wt% of an abrasive. (Note 4) The polishing composition according to Appendix 1, wherein the abrasive is a ceria abrasive. (Note 5) The polishing composition according to Appendix 1, wherein the pH of the polishing composition is approximately 5.5 to approximately 7. (Note 6) The polishing composition according to Appendix 5, wherein the pH of the polishing composition is approximately 6 to approximately 6.5. (Note 7) The polishing composition according to Appendix 1, wherein the self-stopping agent is selected from hydroxamic acid, acetohydroxamic acid, benzhydroxamic acid, salicylic acid, and combinations thereof. (Note 8) The polishing composition according to Appendix 7, wherein the self-stopping agent is benzhydroxamic acid. (Note 9) The polishing composition according to Appendix 1, wherein the chemical mechanical polishing composition further comprises a nonionic polymer. (Note 10) The polishing composition according to Appendix 9, wherein the nonionic polymer is selected from polyalkylene glycol, polyetheramine, polyethylene oxide / polypropylene oxide copolymer, polyacrylamide, polyvinylpyrrolidone, siloxane polyalkylene oxide copolymer, hydrophobic modified polyacrylate copolymer, hydrophilic nonionic polymer, polysaccharides, and combinations thereof. (Note 11) The polishing composition according to Appendix 10, wherein the nonionic polymer is a polyethylene oxide / polypropylene oxide copolymer. (Note 12) The cationic monomer compounds include 2-(dimethylamino)ethyl acrylate ("DMAEA"), 2-(dimethylamino)ethyl methacrylate ("DMAEM"), 3-(dimethylamino)propyl methacrylamide ("DMAPMA"), 3-(dimethylamino)propyl acrylamide ("DMAPA"), 3-methacrylamidepropyl-trimethyl-ammonium chloride ("MAPTAC"), 3-acrylamidopropyl-trimethyl-ammonium chloride ("APTAC"), and diallyldimethylammonium chloride. Polishing compositions as described in Appendix 1, selected from d ("DADMAC"), 2-(acryloyloxy)-N,N,N-trimethylethaneaminium chloride ("DMAEA.MCQ"), 2-(methacryloyloxy)-N,N,N-trimethylethaneaminium chloride ("DMAEM.MCQ"), N,N-dimethylaminoethyl acrylate benzyl chloride ("DMAEA.BCQ"), N,N-dimethylaminoethyl methacrylate benzyl chloride ("DMAEM.BCQ"), salts thereof, and combinations thereof. (Note 13) The polishing composition according to Appendix 12, wherein the cationic monomer compound is diallyldimethylammonium chloride ("DADMAC") or a salt thereof. (Note 14) A method for chemically and mechanically polishing a substrate, (i) Prepare the circuit board, (ii) Prepare a polishing pad, (iii) (a) Abrasives selected from ceria abrasives, zirconia abrasives, and combinations thereof, (b) Formula (I):

change

Claims

1. A chemical mechanical polishing composition, (a) Abrasives selected from ceria abrasives, zirconia abrasives, and combinations thereof, (b) Formula (I): 【Chemistry 1】 A self-deactivating agent selected from the compounds, A self-terminating agent in which R is selected from the group consisting of hydrogen, alkyl, cycloalkyl, aryl, heterocyclic alkyl, and heterocyclic aryl, each of which may be substituted or unsubstituted. (c) Cationic monomer compounds and (d) water and Includes, The pH of the chemical mechanical polishing composition is 5.5 to 8. Chemical mechanical polishing composition.

2. The chemical mechanical polishing composition according to claim 1, wherein the chemical mechanical polishing composition comprises 0.001 wt% to 10 wt% of an abrasive.

3. The chemical mechanical polishing composition according to claim 1, wherein the chemical mechanical polishing composition comprises 0.05 wt% to 5 wt% of an abrasive.

4. The chemical mechanical polishing composition according to claim 1, wherein the abrasive is a ceria abrasive.

5. The chemical mechanical polishing composition according to claim 1, wherein the pH of the chemical mechanical polishing composition is 5.5 to 7.

6. The chemical mechanical polishing composition according to claim 5, wherein the pH of the chemical mechanical polishing composition is 6 to 6.

5.

7. The chemical mechanical polishing composition according to claim 1, wherein the self-stopping agent is selected from hydroxamic acid, acetohydroxamic acid, benzhydroxamic acid, salicylic acid, and combinations thereof.

8. The chemical machinery polishing composition according to claim 7, wherein the self-deactivating agent is benzhydroxamic acid.

9. The chemical mechanical polishing composition according to claim 1, wherein the chemical mechanical polishing composition further comprises a nonionic polymer.

10. The chemical mechanical polishing composition according to claim 9, wherein the nonionic polymer is selected from polyalkylene glycol, polyetheramine, polyethylene oxide / polypropylene oxide copolymer, polyacrylamide, polyvinylpyrrolidone, siloxane polyalkylene oxide copolymer, hydrophobic modified polyacrylate copolymer, hydrophilic nonionic polymer, polysaccharides, and combinations thereof.

11. The chemical mechanical polishing composition according to claim 10, wherein the nonionic polymer is a polyethylene oxide / polypropylene oxide copolymer.

12. The cationic monomer compound is 2-(dimethylamino)ethyl acrylate ("DMAEA"), 2-(dimethylamino)ethyl methacrylate ("DMAEM"), 3-(dimethylamino)propyl methacrylamide ("DMAPMA"), 3-(dimethylamino)propyl acrylamide ("DMAPA"), 3-methacrylamidepropyl-trimethyl-ammonium chloride ("MAPTAC"), 3-acrylamidopropyl-trimethyl-ammonium chloride ("APTAC"), diallyldimethylammonium chloride ( A chemical mechanical polishing composition according to claim 1, selected from "DADAMC", 2-(acryloyloxy)-N,N,N-trimethylethaneaminium chloride ("DMAEA.MCQ"), 2-(methacryloyloxy)-N,N,N-trimethylethaneaminium chloride ("DMAEM.MCQ"), N,N-dimethylaminoethyl acrylate benzyl chloride ("DMAEA.BCQ"), N,N-dimethylaminoethyl methacrylate benzyl chloride ("DMAEM.BCQ"), salts thereof, and combinations thereof.

13. The chemical mechanical polishing composition according to claim 12, wherein the cationic monomer compound is diallyldimethylammonium chloride ("DADMAC") or a salt thereof.

14. A method for chemically and mechanically polishing a substrate, (i) Prepare the circuit board, (ii) Prepare a polishing pad, (iii) Chemical mechanical polishing composition, (a) Abrasives selected from ceria abrasives, zirconia abrasives, and combinations thereof, (b) Formula (I): 【Chemistry 2】 A self-deactivating agent selected from the compounds, A self-terminating agent in which R is selected from the group consisting of hydrogen, alkyl, cycloalkyl, aryl, heterocyclic alkyl, and heterocyclic aryl, each of which may be substituted or unsubstituted. (c) Cationic monomer compounds and (d) water and Includes, The pH of the chemical machinery polishing composition is 5.5 to 8. Prepare a chemical mechanical polishing composition, (iv) The substrate is brought into contact with the polishing pad and the chemical mechanical polishing composition, and (v) Polishing the substrate by moving the polishing pad and the chemical mechanical polishing composition over the substrate, thereby polishing the substrate. A method for chemically and mechanically polishing a substrate, including the following.

15. The method according to claim 14, wherein the chemical mechanical polishing composition comprises 0.001 wt% to 10 wt% of an abrasive.

16. The method according to claim 15, wherein the chemical mechanical polishing composition comprises 0.05 wt% to 5 wt% of an abrasive.

17. The method according to claim 14, wherein the abrasive is a ceria abrasive.

18. The method according to claim 14, wherein the pH of the chemical mechanical polishing composition is 5.5 to 7.

19. The method according to claim 18, wherein the pH of the chemical mechanical polishing composition is 6 to 6.

5.

20. The method according to claim 14, wherein the self-deactivating agent is selected from hydroxamic acid, acetohydroxamic acid, benzhydroxamic acid, salicylic acid, and combinations thereof.

21. The method according to claim 20, wherein the self-deactivating agent is benzhydroxamic acid.

22. The method according to claim 14, wherein the chemical mechanical polishing composition further comprises a nonionic polymer.

23. The method according to claim 22, wherein the nonionic polymer is selected from polyalkylene glycol, polyetheramine, polyethylene oxide / polypropylene oxide copolymer, polyacrylamide, polyvinylpyrrolidone, siloxane polyalkylene oxide copolymer, hydrophobic modified polyacrylate copolymer, hydrophilic nonionic polymer, polysaccharides, and combinations thereof.

24. The cationic monomer compounds include 2-(dimethylamino)ethyl acrylate ("DMAEA"), 2-(dimethylamino)ethyl methacrylate ("DMAEM"), 3-(dimethylamino)propyl methacrylamide ("DMAPMA"), 3-(dimethylamino)propyl acrylamide ("DMAPA"), 3-methacrylamidepropyl-trimethyl-ammonium chloride ("MAPTAC"), 3-acrylamidepropyl-trimethyl-ammonium chloride ("APTAC"), and diallyldimethylammonium. The method according to claim 14, selected from chloride ("DADMAC"), 2-(acryloyloxy)-N,N,N-trimethylethaneaminium chloride ("DMAEA.MCQ"), 2-(methacryloyloxy)-N,N,N-trimethylethaneaminium chloride ("DMAEM.MCQ"), N,N-dimethylaminoethyl acrylate benzyl chloride ("DMAEA.BCQ"), N,N-dimethylaminoethyl methacrylate benzyl chloride ("DMAEM.BCQ"), salts thereof, and combinations thereof.

25. The method according to claim 24, wherein the cationic monomer compound is diallyldimethylammonium chloride ("DADMAC") or a salt thereof.

Images