Provided is a method that is for polishing a silicon wafer by a polishing device using a carrier holding the silicon wafer, and that can reduce wear on the carrier. In this polishing method, a polishing liquid used in the polishing device contains 0.1-5 mass %, in terms of the concentration of silica, silica particles comprising: silica particles (A) having an average primary particle size of 4-30 nm as measured by BET, and having an (X2/X1) ratio of 1.2-1.8, where X2 (nm) represents an average particle size along the major axis thereof as calculated from a perspective projection image obtained using an electron beam, and X1 (nm) represents the average primary particle size as measured by BET; and silica particles (B) having an average primary particle size of more than 30 nm but not more than 50 nm as measured by BET, and having a (X2/X1) ratio of 1.2-1.8, where X2 (nm) represents an average particle size along the major axis thereof as calculated from a perspective projection image obtained using an electron beam, and X1 (nm) represents the average primary particle size as measured by BET, wherein the mass ratio of the silica particles (A) to the silica particles (B) is 100:0 to 85:15.

A detergent composition and a polishing composition are provided. The detergent composition facilitates sufficient removal of polishing agents, metal microparticles, and anticorrosives in cleaning of a semiconductor substrate and long-term maintenance of flatness of a metal wiring surface after cleaning and achieves excellent quality stability for a long period of time; and the polishing composition facilitates suppression of scratching on a polished object such as a semiconductor substrate, and reduction of filter clogging. A detergent composition containing an alkanol hydroxylamine compound represented by General Formula (1) and having a pH of 10 to 13, and a chemical-mechanical polishing composition containing the detergent composition and a polishing agent. In Formula (1), R.sup.a1 and R.sup.a2 are the same or different and each represents a hydrogen atom or an alkyl group having from 1 to 10 carbons and having from 1 to 3 hydroxyl groups, with proviso that R.sup.a1 and R.sup.a2 are not simultaneously hydrogen atoms, and a total number of hydroxyl groups present in R.sup.a1 and R.sup.a2 is not 0.

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An aspect of the present disclosure provides a CMP polishing liquid for polishing polysilicon, the CMP polishing liquid containing: abrasive grains; and a cationic polymer, in which the cationic polymer includes at least one selected from the group consisting of a polymer A having a main chain containing a nitrogen atom and a carbon atom and a hydroxyl group bonded to the carbon atom and an allylamine polymer B. Another aspect of the present disclosure provides a polishing method including a step of polishing a material to be polished by using this CMP polishing liquid.

A silicon carbide substrate is composed of silicon carbide, and when a main surface thereof is etched with chlorine gas, the overall length of linear etch-pit groups observed in the main surface is equal to or less than the diameter of the substrate.

A silica-based particle dispersion including a silica-based particle group and a high polishing rate and high surface precision is achieved to a silica-based substrate or a NiP-plated substrate to be polished or the like. A silica-based particle dispersion containing a group including irregularly-shaped and non-irregularly-shaped silica-based particles, wherein the irregularly-shaped silica-based particles each have a plurality of small holes thereinside and a covering silica layer which covers the core, and the silica-based particle group satisfies [1]-[3]. [1] Having an average particle size (D.sub.1) of 100-600 nm, and a particle size (D.sub.2) of 30-300 nm in terms of specific surface area. [2] An irregular-shape degree D (D=D.sub.1/D.sub.3) represented by the average particle size (D.sub.1) and a projected area-equivalent particle size (D.sub.3) being in the range of 1.1-5.0. [3] When waveform separation is performed on a volume-reference particle size distribution, a multi-peak distribution in which three or more peaks are detected.

An object of the present invention is to provide a polishing composition which can make the removal rate of a metal material and the removal rate of a resin material the same or close to each other in a chemical mechanical polishing process, which can accordingly avoid or suppress the occurrence of a step difference. The polishing composition contains: abrasive grains containing silica, with at least a part of hydrogen atoms constituting a silanol group located on a surface of the silica being substituted with a cation of at least one metal atom M selected from the group consisting of aluminum, chromium, titanium, zirconium, iron, zinc, tin, scandium, and gallium; and a dispersing medium. The pH of the polishing composition is more than 2 and 7 or less.

A method for producing a liquid dispersion containing irregular-shaped silica particles in which two or more primary particles are linked together, by simultaneously adding a liquid A containing silane alkoxide and a liquid B containing an alkali catalyst and water to a liquid I consisting substantially of an organic solvent to cause hydrolysis and polycondensation of the silane alkoxide, wherein the period from the start of the addition until the silica concentration of the reaction system at the end of the addition reaches 70% is 20% or less of the full reaction time period.

A gas nozzle according to an embodiment of the present invention includes a columnar main body including a ceramic sintered body having a through hole through which gas flows. An outlet of the through hole for the gas is formed on one end face of the main body. An inner wall of the through hole has a first region located in a vicinity of the outlet, and a second region located further inward of the main body than the first region. The first region and the second region each include a sintered surface of the ceramic sintered body. Average crystal grain size in the first region is larger than average crystal grain size in the second region.

Detection of an abnormality in polishing of a substrate is provided. A measuring device measures a position of the polishing tool relative to a surface of the substrate. A controller determines an amount of polishing of the substrate from the position of the polishing tool; calculates a polishing rate from the amount of polishing of the substrate; and judges that an abnormality in polishing of the edge portion of the substrate has occurred if the polishing rate is out of a predetermined range exceeds a predetermined threshold value.

Provided is a polishing composition which is suitable for polishing an object of polishing having a layer containing a high mobility material that has higher carrier mobility than Si, suppresses excessive dissolution of the layer containing a high mobility material, and is capable of efficient polishing.

Disclosed is a polishing composition that is used for polishing an object of polishing having a layer containing a high mobility material that has higher carrier mobility than Si, the polishing composition including abrasive grains and at least one salt compound selected from the group consisting of a salt of a monovalent acid, a salt of a divalent acid, a salt of a trivalent acid, and a halide salt, in which the electrical conductivity is 1 mS/cm or higher, and a content of hydrogen peroxide is less than 0.1% by mass.