US 6,800,360 B2 · Porous ceramics and method of preparing the same as well as microstrip substrate

Abstract

Powder of a metal serving as a precursor for ceramics (1) and a sintering additive are mixed with each other and heat-treated by microwave heating thereby nitriding or oxidizing the metallic powder from the surface thereof and diffusing the metal with a nitride or an oxide formed on the shell of the metal for obtaining porous ceramics (1) having homogeneous and fine closed pores (1a). The porous ceramics (1) according to the present invention, having the closed pores (1a) homogeneously diffusing at a high ratio, exhibits excellent characteristics when applied to an electronic circuit board or the like requiring moisture absorption resistance, low permittivity and low dielectric loss as well as mechanical strength.

Claims17

Dependent claims

Porous ceramics having relative density of lees than 70% with a ratio of closed pores of at least 50% among all pores (1a).

Dependencies are inferred from the claim text.

Facts

Application

10/258,902Filed 29 Oct 2002

Priority

JP 2001-0322458 Feb 2001

Published

US 2004/0076806 A122 Apr 2004

Granted

5 Oct 2004

Term ends

Not estimatedThe source records don’t support an estimate.

Classification39 codes

B24B 37/042
Designed for working plane surfaces: operating processes therefor
C04B 35/581
Based on borides, nitrides, i.e. nitrides, oxynitrides, carbonitrides or oxycarbonitrides or silicides: based on aluminium nitride
C04B 35/591
Based on silicon nitride: obtained by reaction sintering
C04B 35/6303
Using additives specially adapted for forming the products , e.g.. binder binders: inorganic additives

Porous ceramics and method of preparing the same as well as microstrip substrate

Life of this patent

Porous ceramics and method of preparing the same as well as microstrip substrate

Life of this patent

Abstract

Claims17