An abrasive for planarization of glass substrates for hard discs comprising abrasive grains mainly composed of rare earth oxides containing cerium oxide, wherein the abrasive grains has a cerium oxide/total rare earth oxide ratio of 95 wt %.
A dental diamond bur having grains of diamond attached to a head of the bur body with a plated metal layer containing grains of a fluorine compound that are almost uniformly dispersed and have an average diameter smaller than that of the diamond.
A polishing pad for polishing semiconductors and other planar substrates in the presence of a slurry comprising abrasive particles and a dispersive agent is disclosed. The polishing pad includes a soluble component within a polymer matrix component. The soluble component includes particles soluble in the slurry sufficiently to provide a void structure in the polishing surface of the pad. The void structure enhances the polishing rate and uniformity by increasing the mobility of the abrasive particles while reducing scratching of the polished surface. Additives that further enhance polishing and/or assist in the removal of residues generated during polishing, such as surfactants and removers, are optionally incorporated in the soluble particles or topographically coated on the soluble particles.
Cerium oxide powder having carbonate groups and made of crystalline primary particles containing cerium oxide and having carbonate groups on the surface and in a region close to the surface, and having a BET surface area of from 25 to 150 m.sup.2/g, a mean diameter of from 5 to 50 nm, a carbonate concentration in the region close to the surface decreasing inwardly from the surface, a carbon content due to carbonate groups on the surface of from 5 to 50% by area, a carbon content due to carbonate groups at a depth of about 5 nm in a region close to the surface of from 0 to 30% by area, a content of cerium oxide calculated as CeO.sub.2 and based on the powder of at least 99.5% by weight and a content of organic and inorganic carbon of from 0.01 to 0.3% by weight. A dispersion containing this powder.
An improved polishing pad for polishing semi-conductors and other planar substrates in the presence of a slurry which optionally may contain abrasive particles is disclosed. The polishing pad comprises a non-woven fibrous component, a portion which may optionally comprise bicomponent fibers, optionally embedded within a polymer matrix component.
An improved polishing pad for polishing semi-conductors and other planar substrates in the presence of a slurry which optionally may contain abrasive particles is disclosed. The polishing pad comprises a non-woven fibrous component, a portion which may optionally comprise bicomponent fibers, optionally embedded within a polymer matrix component.
