Abstract: A wiring substrate includes first conductor pads formed on a surface of an insulating layer, second conductor pads formed on the surface of the insulating layer, a second insulating layer covering the surface of the insulating layer and first and second conductor pads, first via conductors formed in first via holes penetrating through the second insulating layer such that the first via conductors are formed on the first conductor pads, and second via conductors formed in second via holes penetrating through the second insulating layer such that the second via conductors are formed on the second conductor pads. The first and second conductor pads are formed such that an annular width amount of each second conductor pad is smaller than an annular width amount of each first conductor pad and that a haloing amount in each second conductor pad is smaller than a haloing amount in each first conductor pad.

Abstract: A method for manufacturing a wiring substrate includes forming first conductor pads and second conductor pads having a shorter inter-pad distance than the first conductor pads, forming a second insulating layer covering the first conductor pads and the second conductor pads, forming first via holes exposing the first conductor pads, applying a first desmear treatment such that residues are removed from the first via holes, forming second via holes in the second insulating layer after the first desmear treatment such that the second via holes expose the second conductor pads, applying a second desmear treatment such that residues are removed from the second via holes, forming first via conductors in the first via holes such that the first via conductors are formed on the first conductor pads, and forming second via conductors in the second via holes such that the second via conductor are formed on the second conductor pads.

Abstract: A wiring substrate includes an insulating layer, and a conductor layer including a wiring formed on the insulating layer. The wiring in the conductor layer has a first section and a second section formed such that a wiring width in the second section is smaller than a wiring width in the first section and that a wiring thickness in the second section is larger than a wiring thickness in the first section.

Abstract: A wiring substrate includes an insulating layer, a conductor layer formed on the insulating layer and including a conductor pad having a rectangular planar shape, and a solder resist layer formed on the insulating layer such that the solder resist layer is covering the conductor layer formed on the insulating layer. The solder resist layer has an opening formed such that the opening is exposing 50% or more of an area of a surface of the conductor pad on the opposite side with respect to the insulating layer and exposing a side surface and the surface of the conductor pad at side portions of a peripheral edge of the conductor pad and that the solder resist layer is covering the side surface and the surface of the conductor pad at one or more of corner portions of the peripheral edge of the conductor pad.

Abstract: A printed wiring board includes a conductor layer including first and second pads, a coating layer covering the conductor layer and having first opening exposing the first pad and second opening exposing the second pad, and metal bumps including a first bump on the first pad and a second bump on the second pad such that the first and second bumps protrude from the coating layer. The first and second openings are formed such that diameter of the second pad is smaller than diameter of the first pad. The first and second bumps are formed such that height of protruding portion of the first bump from the surface of the coating layer is substantially equal to height of protruding portion of the second bump from the surface of the coating layer and that the second bump covers an area of the coating layer on the surface surrounding the second opening.

Abstract: A printed wiring board includes a conductor layer including first and second pads, a coating layer covering the conductor layer and having first opening exposing the first pad and second opening exposing the second pad, and metal bumps including a first bump on the first pad and a second bump on the second pad such that the first and second bumps protrude from the coating layer. The first and second openings are formed such that diameter of the second pad is smaller than diameter of the first pad. The first and second bumps are formed such that height of protruding portion of the first bump from the surface of the coating layer is substantially equal to height of protruding portion of the second bump from the surface of the coating layer and that the second bump covers an area of the coating layer on the surface surrounding the second opening.