A foaming thermoplastic polyurethane resin is a reaction product of a polyisocyanate component containing a bis(isocyanatomethyl)cyclohexane and a polyol component. In a peak of chromatogram obtained by measurement of the foaming thermoplastic polyurethane resin with gel permeation chromatography, the area of a high molecular weight component having a weight average molecular weight of 400,000 or more with respect to the total area of the peak is 25% or more and 60% 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).

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).

An object of the present invention is to provide a nanobubble-containing inorganic oxide fine particle dispersion having excellent concentration stability in a process used as an abrasive. The object is achieved by the nanobubble-containing inorganic oxide fine particle dispersion including: inorganic oxide fine particles having an average particle size of 1 to 500 nm and containing fine particles containing Ce; and nanobubbles having an average cell size of 50 to 500 nm and being at least one non-oxidizing gas selected from a group consisting of N.sub.2 and H.sub.2.

A wafer processing method includes: a bonding step of bonding a front surface side of a first wafer chamfered at a peripheral edge portion thereof to a front surface side of a second wafer; a grinding step of holding a back surface side of the second wafer by a chuck table and grinding a back surface of the first wafer to thin the first wafer to a finished thickness, after the bonding step; and a modified layer forming step of applying along a boundary between a device region and a peripheral surplus region of the first wafer a laser beam of such a wavelength as to be transmitted through the first wafer to form an annular modified layer inside the first wafer in the vicinity of the front surface of the first wafer, before the grinding step.

A method of chemical mechanical polishing (CMP) includes providing a slurry solution including at least one per-compound permanganate oxidizer in a concentration between 0.01 M and 2 M, with a pH level from 1.5 to 5 or from 8 to 11, and at least one buffering agent. The buffering agent is different from this pure-compound permanganate oxidizer, and comprises a surfactant and/or an alkali metal ion. The slurry solution is exclusive of any added particles. The slurry solution is dispensed on a hard surface having a Vickers hardness >1,000 kg/mm.sup.2 and is pressed by a polishing pad with the slurry solution in between while rotating the polishing pad relative to the hard surface.

A method of chemical mechanical polishing (CMP) includes providing a slurry solution including at least one per-compound permanganate oxidizer in a concentration between 0.01 M and 2 M, with a pH level from 1.5 to 5 or from 8 to 11, and at least one buffering agent. The buffering agent is different from this pure-compound permanganate oxidizer, and comprises a surfactant and/or an alkali metal ion. The slurry solution is exclusive of any added particles. The slurry solution is dispensed on a hard surface having a Vickers hardness >1,000 kg/mm.sup.2 and is pressed by a polishing pad with the slurry solution in between while rotating the polishing pad relative to the hard surface.

According a method for manufacturing a semiconductor device of the present invention, a surface protection film having an elastic modulus of 2 GPa or more is formed on a first main surface of a semiconductor wafer where an element structure is formed, the semiconductor wafer is placed on a stage with the first main surface facing the stage, and a second main surface of the semiconductor wafer opposite to the first main surface is ground.

A polishing agent for a synthetic quartz glass substrate contains polishing particles and water. The polishing particles contain silica particles as base particles, and composite oxide particles of cerium and at least one rare earth element selected from trivalent rare earth elements other than cerium are supported on surfaces of the base particles. This provides a polishing agent for a synthetic quartz glass substrate, the polishing agent having high polishing rate and being capable of sufficiently reducing generation of defects due to polishing.

A polishing agent containing abrasive grains and water, in which the abrasive grains contain silica particles, an average particle diameter R.sub.ave of the abrasive grains is 50 nm or more, a ratio R.sub.ave/R.sub.min of the average particle diameter R.sub.ave to an average minor diameter R.sub.min of the abrasive grains is 1.0 to 2.0, and a zeta potential of the abrasive grains in the polishing agent is positive.