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.

A wiring substrate includes an insulating substrate, a conductor and an Ni film. The insulating substrate has a first surface and a second surface on a side opposite the first surface, and contains AlN. The conductor is disposed on the first surface and contains Cu. The Ni film is disposed so as to extend across an upper surface and a side surface of the conductor to the first surface. Ti oxide is scattered so as to be at a plurality of points on the first surface.

A wiring substrate includes an insulating substrate, a conductor and an Ni film. The insulating substrate has a first surface and a second surface on a side opposite the first surface, and contains AlN. The conductor is disposed on the first surface and contains Cu. The Ni film is disposed so as to extend across an upper surface and a side surface of the conductor to the first surface. Ti oxide is scattered so as to be at a plurality of points on the first surface.

The invention relates to a method for manufacturing a composite component of a timepiece or of a jewelry part, the composite component comprising a porous ceramic part and a metallic material filling the pores of said ceramic part, said method comprising the steps of: providing a porous ceramic preform of the component, providing a metallic material, heating the metallic material to a temperature higher than the melting point of the metallic material, filling the pores of the ceramic preform with the molten metallic material, cooling the metallic material and the ceramic preform to obtain a solidified metallic material in the pores of the ceramic preform, and applying finishing treatments to obtain the composite component,

wherein said porous ceramic preform consists essentially of a material selected from the group consisting of Si.sub.3N.sub.4, SiO.sub.2 and mixtures thereof, and said metallic material is selected from the group consisting of gold, platinum, palladium metals and alloys of these metals.

The invention relates also to a composite component of a timepiece or of a jewelry part comprising a porous ceramic part and a metallic material filling the pores of said ceramic part, wherein said porous ceramic part consists essentially of a material selected from the group consisting of Si.sub.3N.sub.4, SO.sub.2 and mixtures thereof, and said metallic material which is selected from the group consisting of gold, platinum, palladium metals and alloys of these metals.

The invention relates to a method for manufacturing a composite component of a timepiece or of a jewelry part, the composite component comprising a porous ceramic part and a metallic material filling the pores of said ceramic part, said method comprising the steps of: providing a porous ceramic preform of the component, providing a metallic material, heating the metallic material to a temperature higher than the melting point of the metallic material, filling the pores of the ceramic preform with the molten metallic material, cooling the metallic material and the ceramic preform to obtain a solidified metallic material in the pores of the ceramic preform, and applying finishing treatments to obtain the composite component,

wherein said porous ceramic preform consists essentially of a material selected from the group consisting of Si.sub.3N.sub.4, SiO.sub.2 and mixtures thereof, and said metallic material is selected from the group consisting of gold, platinum, palladium metals and alloys of these metals.

The invention relates also to a composite component of a timepiece or of a jewelry part comprising a porous ceramic part and a metallic material filling the pores of said ceramic part, wherein said porous ceramic part consists essentially of a material selected from the group consisting of Si.sub.3N.sub.4, SO.sub.2 and mixtures thereof, and said metallic material which is selected from the group consisting of gold, platinum, palladium metals and alloys of these metals.

Provided is a method for manufacturing a circuit board including: (a) preparing a mixture of a metal powder, an anti-sintering agent, and an activator; (b) immersing a dielectric substrate in the mixture; (c) forming a metal-containing layer on the surface of the dielectric substrate by heating the mixture under an inert atmosphere or under a reducing atmosphere; (d) forming a first metal layer on the metal-containing layer by electroless plating and forming a second metal layer thereon by electroplating; and (e) forming a metal pattern on the dielectric substrate, wherein the first metal layer includes Cu, Ni, Co, Au, Pd, or an alloy thereof, the second metal layer includes Cu, Ni, Fe, Co, Cr, Zn, Au, Ag, Pt, Pd, Rh, or an alloy thereof, and the method further includes performing heat treatment at least once after step (c).

Provided is a method for manufacturing a circuit board including: (a) preparing a mixture of a metal powder, an anti-sintering agent, and an activator; (b) immersing a dielectric substrate in the mixture; (c) forming a metal-containing layer on the surface of the dielectric substrate by heating the mixture under an inert atmosphere or under a reducing atmosphere; (d) forming a first metal layer on the metal-containing layer by electroless plating and forming a second metal layer thereon by electroplating; and (e) forming a metal pattern on the dielectric substrate, wherein the first metal layer includes Cu, Ni, Co, Au, Pd, or an alloy thereof, the second metal layer includes Cu, Ni, Fe, Co, Cr, Zn, Au, Ag, Pt, Pd, Rh, or an alloy thereof, and the method further includes performing heat treatment at least once after step (c).

Provided is a method for manufacturing a circuit board including: (a) preparing a mixture of a metal powder, an anti-sintering agent, and an activator; (b) immersing a dielectric substrate in the mixture; (c) forming a metal-containing layer on the surface of the dielectric substrate by heating the mixture under an inert atmosphere or under a reducing atmosphere; (d) forming a first metal layer on the metal-containing layer by electroless plating and forming a second metal layer thereon by electroplating; and (e) forming a metal pattern on the dielectric substrate, wherein the first metal layer includes Cu, Ni, Co, Au, Pd, or an alloy thereof, the second metal layer includes Cu, Ni, Fe, Co, Cr, Zn, Au, Ag, Pt, Pd, Rh, or an alloy thereof, and the method further includes performing heat treatment at least once after step (c).

Provided is a method for manufacturing a circuit board including: (a) preparing a mixture of a metal powder, an anti-sintering agent, and an activator; (b) immersing a dielectric substrate in the mixture; (c) forming a metal-containing layer on the surface of the dielectric substrate by heating the mixture under an inert atmosphere or under a reducing atmosphere; (d) forming a first metal layer on the metal-containing layer by electroless plating and forming a second metal layer thereon by electroplating; and (e) forming a metal pattern on the dielectric substrate, wherein the first metal layer includes Cu, Ni, Co, Au, Pd, or an alloy thereof, the second metal layer includes Cu, Ni, Fe, Co, Cr, Zn, Au, Ag, Pt, Pd, Rh, or an alloy thereof, and the method further includes performing heat treatment at least once after step (c).