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.

An object of the present invention is to provide a polishing composition that can achieve both a high polishing removal rate and high surface quality. According to the present invention, provided is a polishing composition for polishing a material to be polished. The polishing composition contains sodium metavanadate, hydrogen peroxide, and silica abrasive. The content C1 of sodium metavanadate is 0.7% to 3.5% by weight, the content C2 of hydrogen peroxide is 0.3% to 3% by weight, and the content C3 of the silica abrasive is 12% to 50% by weight.

Provided are a polishing composition capable of achieving both a high polishing removal rate and high surface quality in polishing a gallium oxide substrate, and a method for polishing and a method for manufacturing a gallium oxide substrate using the polishing composition. According to the art disclosed herein, provided is a polishing composition used for polishing a gallium oxide substrate. This polishing composition contains abrasive and water. By polishing with such a polishing composition, it is possible to improve the polishing removal rate for the gallium oxide substrate and realize a gallium oxide substrate having good surface quality.

Provided is a polishing liquid composition that is able to improve the polishing rate of a silicon oxide film in one aspect.

An aspect of the present disclosure relates to a polishing liquid composition for a silicon oxide film. The polishing liquid composition contains cerium oxide particles (component A), an additive (component B), and an aqueous medium. The component B is a compound having a reduction potential of (145 V or more when a 10 ppm aqueous solution of the component B is measured by cyclic voltammetry (with an Ag/AgCl electrode as a reference).

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.

A method of training a neural network includes obtaining two ground truth thickness profiles a test substrate, obtaining two thickness profiles for the test substrate as measured by an in-situ monitoring system while the test substrate is on polishing pads of different thicknesses, generating an estimated thickness profile for another thickness value that is between the two thickness values by interpolating between the two profiles, and training a neural network using the estimated thickness profile.

Provided is a polishing composition capable of speeding up a mirror polishing in terms of polishing rate and the like, improving the smoothness and the flatness of a wafer surface of a semiconductor wafer after the mirror polishing, enabling mirror finishing with high processing accuracy, and having excellent storage stability.

The polishing composition is for polishing a polishing target including a group III-V compound as a constituent component, and includes colloidal silica, an oxidizing agent, an oxidation accelerator for accelerating the oxidation reaction on the surface of the polishing target by the oxidizing agent, a stabilizer for controlling the accelerating action of the oxidation reaction on the surface of the polishing target by the oxidation accelerator, and water.

An object of the present invention is to provide a polishing composition that can achieve both a high polishing removal rate and high surface quality. According to the present invention, provided is a polishing composition for polishing a material to be polished. The polishing composition contains sodium metavanadate, hydrogen peroxide, and silica abrasive. The content C1 of sodium metavanadate is 0.7% to 3.5% by weight, the content C2 of hydrogen peroxide is 0.3% to 3% by weight, and the content C3 of the silica abrasive is 12% to 50% by weight.

There is provided a method of manufacturing package devices, including a first substrate preparing step of preparing a first substrate in which a device chip is mounted in each of a plurality of mounting areas, a second substrate preparing step of preparing a second substrate including a plurality of recessed portions that are capable of housing the device chips, a bonding step of bonding the first substrate and the second substrate together in such a manner that the device chips are housed in the recessed portions, a grinding step of grinding the second substrate until the recessed portions are exposed, a resin molding step of supplying resin to the plurality of recessed portions and covering the device chips by the resin, and a dividing step of dividing the first substrate and the second substrate and manufacturing a plurality of package devices each including the device chips.

In one aspect, the present disclosure provides a polishing liquid composition for a silicon oxide film that can achieve both of an improved polishing rate for a silicon oxide film and a reduced line width dependence of the polishing rate at raised areas in a pattern layer of raised and trench areas.

One aspect of the present disclosure is directed to a polishing liquid composition for a silicon oxide film that contains: cerium oxide particles (component A); a compound represented by Formula (I) or Formula (II) below (component B); a nitrogen-containing heteroaromatic compound in which at least one hydrogen atom is substituted with a hydroxyl group (component C); and an aqueous medium.

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