A method for manufacturing a wafer product, including the steps of: chamfering a circumferential edge portion of a wafer; lapping or double-side grinding main surfaces thereof; etching; mirror-polishing the main surface; and mirror-polishing the chamfered portion. The chamfered portion has a cross-sectional shape including: a first inclined portion continuous from the first main surface; a first arc portion continuous from the first inclined portion and having a radius of curvature; a second inclined portion continuous from the second main surface; a second arc portion continuous from the second inclined portion and having a radius of curvature; and an end portion connecting the first arc portion to the second arc portion. This provides a method for manufacturing a wafer by which a variation in a chamfered cross-sectional shape in a circumferential direction caused by etching can be suppressed.

A polishing liquid, which is used for chemical mechanical polishing, includes ceria particles having an average aspect ratio of 1.5 or more; and an anionic polymer or a cationic polymer, in which a pH of the polishing liquid is 3 to 8. In a case where the polishing liquid contains the anionic polymer, the polishing liquid further includes an inorganic acid or an organic acid including at least one group selected from the group consisting of a carboxylic acid group, a phosphoric acid group, a phosphonic acid group, and a sulfonic acid group.

The present invention provides a polishing composition with which polishing rates can be effectively improved and which is for polishing works to be polished. The polishing composition comprises water, abrasive grains, an oxidant, and a polishing accelerator. The polishing accelerator comprises at least one metal salt selected from the group consisting of alkali metal salts and alkaline-earth metal salts.

A wax coating apparatus for wafer mounting of the embodiment includes: a vacuum chuck in which a vacuum flow path providing vacuum pressure is embedded; a heating plate mounted on an upper side of the vacuum chuck and having holes and grooves connected to the vacuum flow path of the vacuum chuck in order to suck a block to which a wafer is adhered; a rotating shaft connected to a lower side of the vacuum chuck; a driving motor for rotating the rotating shaft; and a wax nozzle provided to be spaced apart from the upper side of the vacuum chuck, wherein the heating plate may be operated so as to heat the block while the wax nozzle sprays wax on the block.

A method for producing a dispersion liquid of silica particles, by simultaneously adding a liquid A containing silane alkoxide and a liquid B containing an alkali catalyst and water to a liquid I containing silica seed particles to cause the particles to grow, so as to produce silica particles; wherein the variation rate of the mole ratio of the alkali catalyst to silica components in the reaction system during a period from the start to the end of the addition relative to the initial mole ratio is 0.90 to 1.10; and the variation rate of the mole ratio of water to the silica components in the reaction system during a period from the start to the end of the addition relative to the initial mole ratio is 0.90 to 1.10.

Letting a particle diameter be Dx (μm) 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 μm or less, and a difference between D95 and D5 is 3 μm or more.

Provided is a linear movable rotary union including a driving shaft comprising a plurality of fluid supply paths; a hollow middle housing surrounding an outside of the driving shaft and comprising a plurality of first through holes in a sidewall; a plurality of first sealing members provided between the middle housing and the driving shaft to prevent leakage of a fluid; a hollow outer housing surrounding an outside of the middle housing and comprising a plurality of second through holes in a sidewall; and a plurality of second sealing members provided between the middle housing and the outer housing to prevent leakage of the fluid, and wherein the driving shaft is installed to be capable of rotational motion in the middle housing, and the middle housing is installed to be capable of reciprocating motion in an axial direction in the outer housing.

A method includes forming a film over a substrate; increasing a surface roughness of the film; and planarizing the film using a first chemical mechanical planarization (CMP) process after increasing the surface roughness.

A substrate-cleaning apparatus may include a tilting arm to which a roll brush and a motor are coupled, a support arm positioned on the tilting arm, a first spring and a second spring coupling the tilting arm to the support arm, a first air bag and a second air bag mounted between the tilting arm and the support arm, and a controller configured to adjust an internal pressure of each of the first air bag and the second air bag. The controller may adjust a difference in internal pressure between the first air bag and the second air bag to control the inclination of the roll brush, and may adjust the internal pressure of each of the first air bag and the second air bag to move the roll brush vertically.

A polishing agent for a synthetic quartz glass substrate, containing polishing particles and water includes ceria 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.