Abstract: A planar antenna includes a multilayer ceramic body 10 having an upper surface and a lower surface, and including a plurality of ceramic layers stacked together, at least one radiation conductor 31 positioned at one of interfaces between the plurality of ceramic layers in the multilayer ceramic body or on the upper surface of the multilayer ceramic body, a ground conductor 32 positioned at another one of the interfaces between the plurality of ceramic layers in the multilayer ceramic body or on the lower surface of the multilayer ceramic body, and a low-dielectric-constant region 115 positioned in the multilayer ceramic body between the radiation conductor and the ground conductor, and having a plurality of hollow portions.

Abstract: A method of producing a multi-layer ceramic substrate includes the steps of: (A) preparing a first ceramic green sheet with a thermal expansion layer arranged thereon, and at least one second ceramic green sheet with no thermal expansion layer arranged thereon; (B) laminating the first and second ceramic green sheets with the thermal expansion layer sandwiched therebetween, thereby obtaining a green sheet laminate; (C) pressure-bonding together the ceramic green sheets of the green sheet laminate; (D) heating and thereby expanding the thermal expansion layer in the pressure-bonded green sheet laminate; (E) extracting a portion of the green sheet laminate that has been displaced the expansion of the thermal expansion layer, thereby forming a cavity in the green sheet laminate; and (F) sintering the green sheet laminate with the cavity formed therein.

Abstract: A conductive paste comprising 88-94% by mass of Ag powder having an average particle size of 3 ?m or less and 0.1-3% by mass of Pd powder, the total amount of the Ag powder and the Pd powder being 88.1-95% by mass. A multilayer ceramic substrate obtained by laminating and sintering pluralities of ceramic green sheets, and having conductor patterns and via-conductors inside, the via-conductors being formed in via-holes having diameters of 150 ?m or less after sintering, containing Ag crystal particles having a particle size of 25 ?m or more, and having a porosity of 10% or less.

Abstract: A multilayer ceramic substrate in which an active element and a passive element are surface-equipped over the outermost surface on one side is provided. The multilayer ceramic substrate comprises a plurality of laminated ceramic substrate layers, a surface layer terminal electrode provided in a via hole of an outermost ceramic substrate layer on at least one side and having a surface layer via electrode and a metal plating layer deposited over an end surface of the surface layer via electrode, and a via conductor which connects the surface layer terminal electrode and circuit patterns over the ceramic substrate layer at the inside, wherein a via hole size of a surface layer terminal electrode for connection of the active element is smaller than a via hole size of a surface layer terminal electrode for connection of the passive element.

Abstract: A multilayer ceramic substrate in which an active element and a passive element are surface-equipped over the outermost surface on one side is provided. The multilayer ceramic substrate comprises a plurality of laminated ceramic substrate layers, a surface layer terminal electrode provided in a via hole of an outermost ceramic substrate layer on at least one side and having a surface layer via electrode and a metal plating layer deposited over an end surface of the surface layer via electrode, and a via conductor which connects the surface layer terminal electrode and circuit patterns over the ceramic substrate layer at the inside, wherein a via hole size of a surface layer terminal electrode for connection of the active element is smaller than a via hole size of a surface layer terminal electrode for connection of the passive element.

Abstract: A conductive paste comprising 88-94% by mass of Ag powder having an average particle size of 3 ?m or less and 0.1-3% by mass of Pd powder, the total amount of the Ag powder and the Pd powder being 88.1-95% by mass. A multilayer ceramic substrate obtained by laminating and sintering pluralities of ceramic green sheets, and having conductor patterns and via-conductors inside, the via-conductors being formed in via-holes having diameters of 150 ?m or less after sintering, containing Ag crystal particles having a particle size of 25 ?m or more, and having a porosity of 10% or less.

Abstract: A multi-layer ceramic substrate having an in-plane shrinkage ratio of 1% or less with 0.1% or less of unevenness, inorganic particles remaining on the external electrodes being 20% or less by mass as a percentage of one or more metals constituting inorganic particles per the total amount of one or more metals constituting the external electrodes and one or more metals constituting the inorganic particles, is produced by (a) preparing a slurry containing ceramic material powder and an organic binder to form low-temperature-sinterable green substrate sheets, (b) laminating the green substrate sheets after forming electrodes thereon, to produce an unsintered multi-layer ceramic substrate, (c) bonding a constraining layer comprising inorganic particles, which are not sintered at the sintering temperature of the unsintered multi-layer ceramic substrate and have an average particle size of 0.3 ?m or more, 0.