Abstract: The present invention relates to a polishing composition for a semiconductor wafer which is excellent in polishing property, and a polishing method. The polishing composition for a semiconductor wafer comprises colloidal silica consisting of non-spherical silica particles having a ratio of long axis to short axis of 1.5 to 15. The polishing method for a semiconductor wafer uses the polishing composition. The polishing composition can provide a remarkably high polishing rate compared with a polishing composition using spherical colloidal silica, and can provide good mirror-polishing without causing scratches. In addition, small alkali metal content enables reduction of adverse effects on a semiconductor wafer, such as residual abrasives after polishing.

Abstract: The present invention relates to a polishing composition for a substrate including a metal such as wiring, etc., formed on a semiconductor wafer, which can provide a high polishing rate without causing scratches on the wiring metal, a method of producing the polishing composition, and a polishing method. The polishing composition for a semiconductor wafer comprises an acid and an aqueous medium dispersion containing positively-charged silica particles having an amino group-containing silane coupling agent bonded on a surface thereof, the polishing composition having a pH of 2 to 6.

Abstract: A polishing composition for semiconductor wafer polishing comprising, colloidal silica prepared from an active silicic acid aqueous solution obtained by removal of alkali from alkali silicate and at least one nitrogen containing basic compound selected from a group consisting of ethylenediamine, diethylenediamine, imidazole, methylimidazole, piperidine, morpholine, arginine, and hydrazine, wherein pH of the colloidal silica is of 8.5 to 11.0 at 25° C. by containing quaternary ammonium hydroxide.

Abstract: Colloidal silica forming nonspherical particles cluster, whose long axis/short axis ratio of silica particles is of 1.2 to 20, and average long axis/short axis ratio of 3 to 15. This colloidal silica can be produced by forming particles by adding basic nitrogen compounds to an active silicic acid aqueous solution, the solution which produced by hydrolysis of tetraalkoxysilane, while heating, then growing particles by using a build up method.

Abstract: A colloidal silica comprising, silica particles inside of which or on the surface of which a nitrogen containing alkaline compound is fixed, wherein said silica particles are prepared by forming and growing colloid particles using the nitrogen containing alkaline compound. Said colloidal silica can be prepared by preparing active silicic acid aqueous solution contacting silicate alkali aqueous solution with cation exchange resin, adding the nitrogen containing alkaline compound and heating, and then growing up particles by build-up method.

Abstract: The polishing compound for semiconductor wafer of the present invention contains colloidal silica composed of silica particles to which tetraethylammonium is fixed, and concentration of silica particles dispersed in water is between 0.5 to 50 weight %. Concentration of tetraethylammonium contained in silica particles to which tetraethylammonium is fixed is desirable to be in the range from 5×10?4 to 2.5×10?2 as indicated by molar ratio of tetraethylammonium/silica.

Abstract: The present invention relates to a polishing composition for a semiconductor wafer which is excellent in polishing property, and a polishing method. The polishing composition for a semiconductor wafer comprises colloidal silica consisting of non-spherical silica particles having a ratio of long axis to short axis of 1.5 to 15. The polishing method for a semiconductor wafer uses the polishing composition. The polishing composition can provide a remarkably high polishing rate compared with a polishing composition using spherical colloidal silica, and can provide good mirror-polishing without causing scratches. In addition, small alkali metal content enables reduction of adverse effects on a semiconductor wafer, such as residual abrasives after polishing.

Abstract: The present invention relates to a polishing composition for a substrate including a metal such as wiring, etc., formed on a semiconductor wafer, which can provide a high polishing rate without causing scratches on the wiring metal, a method of producing the polishing composition, and a polishing method. The polishing composition for a semiconductor wafer comprises an acid and an aqueous medium dispersion containing positively-charged silica particles having an amino group-containing silane coupling agent bonded on a surface thereof, the polishing composition having a pH of 2 to 6.

Abstract: A composition for polishing a semiconductor wafer contains fumed silica particles that are produced by wet grinding using a grinding medium and that have characteristics (A) to (C): (A) a specific surface area in the range of 50 to 200 m2/g measured by a BET method; (B) an average particle diameter in the range of 10 to 50 nm measured by a laser light-scattering method; and (C) an average ratio A/B of the major axis A to the minor axis B of the fumed silica particles in the range of 1.2 to 2.0 measured by TEM observation, wherein the concentration of silica particles containing the fumed silica particles is in the range of 0.5 to 50 weight percent relative to the total weight of an aqueous dispersion.

Abstract: A polishing composition for semiconductor wafers containing colloidal silica is disclosed, wherein the colloidal silica is prepared from an active silicic acid aqueous solution obtained by removing alkali from an alkali silicate aqueous solution and a quaternary ammonium base, and is stabilized with a quaternary ammonium base. The polishing composition contains no alkali metals. The polishing composition contains a buffer solution that is a combination of a weak acid having a pKa from 8.0 to 12.5 at 25° C. (pKa is a logarithm of the reciprocal of acid dissociation constant) and a quaternary ammonium base, and exhibits a buffer action in the range from pH8 to pH11.

Abstract: The present invention provides silicic acid hydrate having a large pore volume and tiny particle diameters, and a process for preparing it. There is disclosed silicic acid hydrate obtained by neutralizing an aqueous solution of sodium silicate with a mineral acid, which has particle properties represented by an oil absorption of 250 to 350 ml/100 g, a total pore volume of 4.0 to 6.0 cc/g, an average pore radius of 200 to 400 .ANG., and an average pore diameter of 3.0 to 15 .mu.m by the laser method, or 2.0 to 4.0 .mu.m by the coulter method, or 0.5 to 3.5 .mu.m by the centrifugal precipitation method.