A silicon nitride powder for sintering which, despite of its fine powdery form, shows a very small increase in the oxygen concentration with time and features excellent storage stability. The silicon nitride powder for sintering has a specific surface area of 5 to 30 m.sup.2/g, and is characterized by having a hydrophobicity (M value) of 30 or more and an increase in the oxygen concentration of 0.30% by mass or less after left to stand in the air of a humidity of 90% and 20° C. for 48 hours. The silicon nitride powder for sintering can be obtained by dry-pulverizing aggregated masses of the silicon nitride in an inert atmosphere in the presence of a silane coupling agent.

A method of manufacturing a plurality of through-holes in a layer of first material, for example for the manufacturing of a probe comprising a tip containing a channel. To manufacture the through-holes in a batch process, a layer of first material is deposited on a wafer comprising a plurality of pits a second layer is provided on the layer of first material, and the second layer is provided with a plurality of holes at central locations of the pits; using the second layer as a shadow mask when depositing a third layer at an angle, covering a part of the first material with said third material at the central locations, and etching the exposed parts of the first layer using the third layer as a protective layer.

A process for producing a silicon nitride powder characterized by comprising a step of providing a starting material powder containing not less than 90% by mass of a silicon powder; the step of filling a heat-resistant reaction vessel with the starting material powder; a step of obtaining a massive product thereof by a combustion synthesis reaction by igniting the starting material powder filled in the reaction vessel in a nitrogen atmosphere and permitting a heat of nitriding combustion of silicon to propagate to the whole starting material powder; and a step of mechanically milling the massive product by a dry method.

The present disclosure relates to a powder composition comprising first and second agglomerates of inorganic particles, to a polymer composition comprising a polymer and said powder composition, and to a composite article made from said polymer composition. The present disclosure further relates to a process for producing said powder composition and to a process for making said composite article, and to the use of said powder composition as thermal conduction means to control the temperature of electrical and electronic components or assemblies or batteries. The present disclosure further relates to a kit of parts for producing said powder composition.

Provided is a method for preparing silicon nitride powder for manufacturing a substrate. The method for preparing silicon nitride powder for manufacturing a substrate, according to an embodiment of the present invention, comprises the steps of: preparing mixed raw material powder comprising metallic silicon powder and crystalline phase control powder; preparing the mixed raw material powder into granules having a predetermined particle size; nitrifying the granules at a predetermined temperature ranging from 1,200-1,500? C. while nitrogen gas is applied to the granules at a predetermined pressure; and pulverizing the nitrified granules. According to the method, it is easy to realize powder having an ? crystal phase at a desired level, and when this is realized as a substrate, a substrate having compact density can be manufactured.

A method of manufacturing a plurality of through-holes in a layer of first material by subjecting part of the layer of said first material to ion beam milling. For batch-wise production, the method comprises after a step of providing the layer of first material and before the step of ion beam milling, providing a second layer of a second material on the layer of first material, providing the second layer of the second material with a plurality of holes, the holes being provided at central locations of pits in the first layer, and subjecting the second layer of the second material to said step of ion beam milling at an angle using said second layer of the second material as a shadow mask.

According to the present invention, there are provided a surface-modified inorganic substance obtained by performing surface modification on a inorganic nitride by using an aldehyde compound such as a compound represented by General Formula I and a resin composition containing the surface-modified inorganic substance and a monomer having a group selected from the group consisting of an oxetanyl group, an oxiranyl group, and a (meth)acrylate group. By using the surface-modified inorganic substance or the resin composition, it is possible to provide a thermally conductive material having excellent thermal conductivity and a device having high durability.

Z.sub.ZX.sub.XCHOGeneral Formula I

(In the formula, Z.sub.Z represents a group selected from the group consisting of an amino group, a thiol group, a hydroxyl group, an isocyanate group, a carboxyl group, a carboxylic acid anhydride group, an oxetanyl group, an oxiranyl group, a (meth)acrylate group, and a hydrogen atom, and X.sub.X represents a divalent linking group.)

A method of manufacturing a plurality of through-holes in a layer of first material, for example for the manufacturing of a probe comprising a tip containing a channel. To manufacture the through-holes in a batch process, a layer of first material is deposited on a wafer comprising a plurality of pits a second layer is provided on the layer of first material, and the second layer is provided with a plurality of holes at central locations of the pits; using the second layer as a shadow mask when depositing a third layer at an angle, covering a part of the first material with said third material at the central locations, and etching the exposed parts of the first layer using the third layer as a protective layer.

A method of manufacturing a plurality of through-holes in a layer of first material by subjecting part of the layer of said first material to ion beam milling.

For batch-wise production, the method comprises after a step of providing the layer of first material and before the step of ion beam milling, providing a second layer of a second material on the layer of first material, providing the second layer of the second material with a plurality of holes, the holes being provided at central locations of pits in the first layer, and subjecting the second layer of the second material to said step of ion beam milling at an angle using said second layer of the second material as a shadow mask.

Provided is a silicon nitride powder containing silicon nitride and carbon, wherein a mass proportion Cp of carbon with respect to the entire powder is 0.05% or more, and wherein a mass proportion Cs of carbon contained in a surface portion of the powder with respect to the entire powder is 0.05% or less. Provided is a method for manufacturing silicon nitride powder, the method including: molding a kneaded material containing a silicon powder and an organic binder to obtain a molded body, degreasing the molded body by heating the molded body at 900 C. or more and less than 1100 C. for 1 hour or more; firing the molded body in a mixed atmosphere containing nitrogen and at least one selected from a group consisting of hydrogen and ammonia to obtain a fired product containing silicon nitride and carbon; and pulverizing the fired product.