A ceramic device including a ceramic material, a patterned metal structure, and a surface activation material is provided. A surface of the ceramic material at least includes a first surface and a second surface that are not coplanar. The ceramic material has recesses on the surface thereof. The patterned metal structure is disposed on the first surface and the second surface. The surface activation material is disposed on a surface of the recesses and located at an interface between the ceramic material and the patterned metal structure.

A method for coating a substrate includes spraying a combination of powders. The combination of powders includes: Hf.sub.0.5Si.sub.0.5O.sub.2; Zr.sub.0.5Si.sub.0.5O.sub.2; and, optionally, at least one of HfO.sub.2 and ZrO.sub.2. A molar ratio of said Hf.sub.0.5Si.sub.0.5O.sub.2 and HfO.sub.2 combined to said Zr.sub.0.5Si.sub.0.5O.sub.2 and ZrO.sub.2 combined is from 2:1 to 4:1. A molar ratio of said Hf.sub.0.5Si.sub.0.5O.sub.2 to said HfO.sub.2 is at least 1:3.

A conductive paste includes a high melting point metal particle having a melting point exceeding a baking temperature, a molten metal particle containing a metal or an alloy which melts at a temperature equivalent to or lower than the baking temperature and has a melting point of 700 C. or lower, an active metal particle containing an active metal, and an organic vehicle.

A conductive paste includes a high melting point metal particle having a melting point exceeding a baking temperature, a molten metal particle containing a metal or an alloy which melts at a temperature equivalent to or lower than the baking temperature and has a melting point of 700 C. or lower, an active metal particle containing an active metal, and an organic vehicle.

A method for producing metal coatings on ceramic substrates for establishing electrical contact, and ceramic substrates having metal coatings. More particularly, the invention relates to the production of weldable and solderable metal coatings on ceramic substrates.

A method for producing metal coatings on ceramic substrates for establishing electrical contact, and ceramic substrates having metal coatings. More particularly, the invention relates to the production of weldable and solderable metal coatings on ceramic substrates.

A superhard polycrystalline construction comprises a body of polycrystalline superhard material comprising a structure comprising superhard material, the structure having porosity greater than 20% by volume and up to around 80% by volume. A method of forming such a superhard polycrystalline construction comprises forming a skeleton structure of a first material having a plurality of voids, at least partially filling some or all of the voids with a second material to form a pre-sinter assembly, and treating the pre-sinter assembly to sinter together grains of superhard material to form a body of polycrystalline superhard material comprising a first region of superhard grains, and an interpenetrating second region; the second region being formed of the other of the first or second material that does not comprise the superhard grains; the superhard grains forming a sintered structure having a porosity greater than 20% by volume and up to around 80% by volume.

Among two main surfaces of a heat dissipation member, one main surface is curved to be convex in an outward direction and the other convex in an inward direction. When a straight line passing through both endpoints P.sub.1 and P.sub.2 of the curve is l.sub.1, a point at which a distance to l.sub.1 on the curve is maximum is P.sub.max, an intersection point between l.sub.1 and a perpendicular drawn from P.sub.max to l.sub.1 is P.sub.3, a middle point of a line segment P.sub.1P.sub.3 is P.sub.4, an intersection point between the curve and a straight line that passes through P.sub.4 and is perpendicular to l.sub.1 is P.sub.mid, a length of the line segment P.sub.1P.sub.3 is L, a length of a line segment P.sub.3P.sub.max is H, and a length of a line segment P.sub.4P.sub.max is h, (2 h/L)/(H/L) is 1.1 or more.

Among two main surfaces of a heat dissipation member, one main surface is curved to be convex in an outward direction and the other convex in an inward direction. When a straight line passing through both endpoints P.sub.1 and P.sub.2 of the curve is l.sub.1, a point at which a distance to l.sub.1 on the curve is maximum is P.sub.max, an intersection point between l.sub.1 and a perpendicular drawn from P.sub.max to l.sub.1 is P.sub.3, a middle point of a line segment P.sub.1P.sub.3 is P.sub.4, an intersection point between the curve and a straight line that passes through P.sub.4 and is perpendicular to l.sub.1 is P.sub.mid, a length of the line segment P.sub.1P.sub.3 is L, a length of a line segment P.sub.3P.sub.max is H, and a length of a line segment P.sub.4P.sub.max is h, (2 h/L)/(H/L) is 1.1 or more.

The dielectric layers are formed from a dielectric porcelain formed from crystal particles containing barium titanate as a main component and containing a rare earth element, and the crystal particles have, in a particle boundary vicinity, a low concentration region in which the concentration of the rare earth element is lower than the concentration of the rare earth element in an inside. The crystal particles further contain vanadium, and the low concentration region contains a larger amount of the vanadium than the amount of the vanadium in the inside. The crystal particles further contain magnesium and manganese, and the magnesium and the manganese have a concentration gradient that is at a maximum at the particle boundary vicinity and that lowers toward the inside.