A method of polishing a substrate is disclosed. The method includes irradiating the substrate with light; measuring intensity of the reflected light; producing spectral waveform representing relationship between relative reflectance and wavelength of the light; performing a Fourier transform process on the spectral waveform to determine a thickness of the film and a corresponding strength of frequency component; determining whether the determined thickness of the film is reliable or not by comparing the strength of frequency component with a threshold value; calculating a defective data rate representing a proportion of the number of unreliable measured values to the total number of measured values; and changing the threshold value based on the defective data rate.

The present invention provides a polishing composition suitable for polishing of a polishing object having a layer containing a Group IV material, the polishing composition making it possible to prevent the dissolution of the Group IV material.

The present invention is a polishing composition which contains an oxidizing agent containing a halogen atom and an organic compound containing an amide bond.

Provided is a composition for polishing silicon wafers, having an excellent effect of reducing haze and having low agglomerating property. A composition for polishing silicon wafers provided here includes: an amido group-containing polymer A; and an organic compound B not containing an amido group. The amido group-containing polymer A has, on a main chain, a building block S derived from a monomer represented by General Formula (1). Molecular weight M.sub.A of the amido group-containing polymer A and molecular weight M.sub.B of the organic compound B have a relation satisfying 200M.sub.B<M.sub.A.

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To reduce scratches during polishing while ensuring an appropriately high polishing rate, provided are a silica for CMP satisfying the following (A) to (C), an aqueous dispersion using a silica for CMP, and a method of producing a silica for CMP: (A) a BET specific surface area of 40 m.sup.2/g or more and 180 m.sup.2/g or less; (B) a particle density measured by a He-gas pycnometer method of 2.24 g/cm.sup.3 or more; and (C) a coefficient of variation in primary particle diameter calculated by TEM/image analysis of 0.40 or less.

To reduce scratches during polishing while ensuring an appropriately high polishing rate, provided are a silica for CMP satisfying the following (A) to (C), an aqueous dispersion using a silica for CMP, and a method of producing a silica for CMP: (A) a BET specific surface area of 40 m.sup.2/g or more and 180 m.sup.2/g or less; (B) a particle density measured by a He-gas pycnometer method of 2.24 g/cm.sup.3 or more; and (C) a coefficient of variation in primary particle diameter calculated by TEM/image analysis of 0.40 or less.

The present invention relates to a substrate processing system and a substrate processing method capable of cleaning a processing-liquid supply line. A substrate processing system includes: a substrate processing apparatus (1) configured to process a substrate W; and a flushing device for cleaning a distribution line (93) and a processing-liquid supply line (92). The flushing device includes: a cleaning-liquid supply line (99) coupled to the distribution line (93); a drain mechanism (101) configured to direct a cleaning liquid, supplied into the processing-liquid supply line (92) through the distribution line (93), to a liquid disposal area (100); a supply switching valve (104) configured to allow only the processing liquid or the cleaning liquid to flow in the distribution line (93); and an operation controller (30) configured to control operations of the drain mechanism (101) and the supply switching valve (104).

A CMP polishing solution containing abrasive grains, an iron ion supplying agent, an organic acid, an oxidizing agent, and an aqueous liquid medium, in which the abrasive grains include silica particles having sulfo groups and silica particles not having sulfo groups.

A polishing pad for a chemical mechanical polishing apparatus includes a polishing layer having a polishing surface and a backing layer formed of a fluid-permeable material. The backing layer includes a lower surface configured to be secured to a platen and an upper surface secured to the polishing layer, wherein the lower surface and upper surface are sealed. A first seal circumferentially seals an edge of the backing layer, and a second seal seals and separates the backing layer into a first region and a second region surrounded by the first region.

Provided is a chemical-mechanical polishing composition comprising an abrasive, a basic component, at least one compound selected from the group consisting of a quaternary polyammonium salt, a quaternary ammonium salt having 6 or more carbon atoms, and an alkylated polymer having an amide structure, and an aqueous carrier; a rinse composition comprising the at least one compound and an aqueous carrier, as well as a method of chemically-mechanically polishing a substrate, and a method of rinsing a substrate, in which the respective compositions are used.

Letting a particle diameter be Dx (m) when a cumulative particle volume cumulated from the small particle diameter side reaches x (%) of the total particle volume in a particle size distribution obtained regarding cerium oxide included in a polishing liquid using a laser diffraction/scattering method, D5 is 1 m or less, D100 is 3 m or more, D50 is 0.8 to 2.4 m, and DpeakD5 is less than D95Dpeak.