Provided are silicon-containing aluminum nitride particles having a high reflectance, a method for producing the same, and a light emitting device. In certain embodiment, silicon-containing aluminum nitride particles having a total amount of aluminum and nitrogen of 90% by mass or more, a content of silicon in a range of 1.5% by mass or more and 4.0% by mass or less, and a content of oxygen in a range of 0.5% by mass or more and 2.0% by mass or less, and having an average reflectance in a wavelength range of 380 nm or more and 730 nm or less of 85% or more.

A method for manufacturing Group-III nitride semiconductor nanoparticles includes synthesizing Group-III nitride semiconductor nanoparticles having a particle size of 16 nm or less by reacting materials containing one or more Group-III elements M in a liquid phase, wherein a coordination solvent is used, and trimethyl M is used as at least one Group-III element material among the materials containing one or more Group-III elements M.

A method for manufacturing Group-III nitride semiconductor nanoparticles includes synthesizing Group-III nitride semiconductor nanoparticles having a particle size of 16 nm or less by reacting materials containing one or more Group-III elements M in a liquid phase, wherein a coordination solvent is used, and trimethyl M is used as at least one Group-III element material among the materials containing one or more Group-III elements M.

A phosphor plate including a base material, and a plate-shaped composite including phosphors dispersed in the base material, in which a main component of the base material is alumina, the phosphor includes an α-type sialon phosphor, and L* value satisfies 73.5 or more and 85.0 or less, a* value satisfies 4.4 or more and 8.0 or less, and b* value satisfies 10.8 or more and 13.0 or less in L*a*b* color coordinates of the phosphor plate in a case of being measured in accordance with JIS Z 8781-4.

In various embodiments, single-crystal aluminum nitride boules and substrates having high transparency to ultraviolet light and low defect density are formed. The single-crystal aluminum nitride may function as a platform for the fabrication of light-emitting devices such as light-emitting diodes and lasers.

In various embodiments, single-crystal aluminum nitride boules and substrates having high transparency to ultraviolet light and low defect density are formed. The single-crystal aluminum nitride may function as a platform for the fabrication of light-emitting devices such as light-emitting diodes and lasers.

An aluminum nitride particle used as a material for an aluminum nitride plate may comprise a carbon content of 100 ppm or less as measured using a pressurized sulfuric acid decomposition method.

An aluminum nitride particle used as a material for an aluminum nitride plate may comprise a carbon content of 100 ppm or less as measured using a pressurized sulfuric acid decomposition method.

An aluminum nitride plate satisfies a “c1>97.5%”, a “c2>97.0%”, a “w1<2.5 degrees”, and a “w1/w2<0.995” where c1 is a c-plane degree of orientation that is defined as a ratio of a diffraction intensity of (002) plane when a surface layer of the aluminum nitride plate is subjected to an X-ray diffraction measurement, and c2 is a c-plane degree of orientation that is defined as a ratio of the diffraction intensity of (002) plane when a portion other than the surface layer of the aluminum nitride plate is subjected to the X-ray diffraction measurement, wherein w1 is a half-value width in an X-ray rocking curve profile of (102) plane of the surface layer and w2 is a half-value width in the X-ray rocking curve profile of (102) plane of the portion other than the surface layer.

An aluminum nitride plate satisfies a “c1>97.5%”, a “c2>97.0%”, a “w1<2.5 degrees”, and a “w1/w2<0.995” where c1 is a c-plane degree of orientation that is defined as a ratio of a diffraction intensity of (002) plane when a surface layer of the aluminum nitride plate is subjected to an X-ray diffraction measurement, and c2 is a c-plane degree of orientation that is defined as a ratio of the diffraction intensity of (002) plane when a portion other than the surface layer of the aluminum nitride plate is subjected to the X-ray diffraction measurement, wherein w1 is a half-value width in an X-ray rocking curve profile of (102) plane of the surface layer and w2 is a half-value width in the X-ray rocking curve profile of (102) plane of the portion other than the surface layer.