A method for forming a circuit board having a dielectric core, a foil top surface, and a thin foil bottom surface with a removable foil backing of sufficient thickness to absorb heat from a laser drilling operation to prevent the penetration of the thin foil bottom surface during laser drilling utilizes a sequence of steps including a laser drilling step, removing the foil backing step, electroless plating step, patterned resist step, electroplating step, resist strip step, tin plate step, and copper etch step, which provide dot vias of fine linewidth and resolution.

A method is disclosed for mounting and cooling a circuit component having aplurality of contacts. The method comprises mounting the circuit component on a rigid substrate of a thermally conductive and electrically insulating material with a circuit board arranged between the circuit component and the substrate. The circuit board, which has a flexible base and carries conductive traces that terminate in contact pads, is secured to the rigid substrate with at least some of the contact pads on the circuit board disposed on the side of the circuit board facing the rigid substrate, at least some of the latter contact pads being bonded to the substrate. To establish both an electrical and a thermal connection between the contacts of the circuit component and the contact pads bonded to the substrate, blind holes are formed in the flexible base of the circuit board, each hole terminating at a respective one of the contact pads bonded to the substrate. The side of the contact pads exposed by the holes is plated to form conductive vias that fill the holes and that are soldered to the contacts of the circuit component.

The method for producing a laminate having a patterned metal foil includes masking the whole surface of a first metal foil in a laminate having the first metal foil, a first insulating resin layer having a thickness of 1 to 200 μm and a second metal foil laminated in this order, and patterning the second metal foil.

A printed wiring board includes a base layer having insulating properties, a first conductive layer directly or indirectly stacked on the base layer front surface, and including a copper foil, a second conductive layer directly or indirectly stacked on the base layer back surface, and including a copper foil, a stacked body for a via hole, the stacked body being stacked on an inner periphery and a bottom of a connection hole that extends through the first conductive layer and the base layer in a thickness direction, and being configured to electrically connect the first conductive layer and the second conductive layer to each other, and having an electroless copper plating layer. Each copper foil contains a copper crystal grain oriented in a plane orientation, and an average crystal grain size of copper of each copper foil is 10 μm or greater, the electroless copper plating layer includes palladium.

A method for manufacturing a printed wiring board includes forming an electroless plating layer on a solder resist layer such that the electroless plating layer has a film thickness in the range of 0.05 μm to 0.70 μm, forming plating resist such that the plating resist has openings exposing portions of the electroless plating layer, applying electrolytic plating such that metal posts are formed in the openings of the plating resist, removing the plating resist, and etching the electroless plating layer exposed from the metal posts. The solder resist layer is formed such that the solder resist layer has openings exposing portions of the outermost conductor layer, the electroless plating layer is formed on the portions of the outermost conductor layer, and the plating resist is formed such that the openings of the plating resist expose the portions of the electroless plating layer formed in the openings of the solder resist layer.

A method for forming a metal film includes forming an oxide layer on a to-be-treated surface of a to-be-treated object by bringing the to-be-treated surface into contact with a reaction solution containing fluorine and an oxide precursor, removing fluorine in the oxide layer, supporting a catalyst on the oxide layer by bringing the oxide layer into contact with a catalyst solution, and depositing a metal film on the oxide layer by bringing the oxide layer into contact with an electroless plating liquid.

A process for making a circuit board modifies a catalytic laminate having a resin rich surface with catalytic particles dispersed below a surface exclusion depth. The catalytic laminate is subjected to a drilling and resin-rich surface removal operation to expose the catalytic particles, followed by an electroless plating operation which deposits a thin layer of conductive material on the surface. A photo-masking step follows to define circuit traces, after which an electro-plating deposition occurs, followed by a resist strip operation and a quick etch to remove electroless copper which was previously covered by photoresist.

To provide a method for manufacturing a laminate body with excellent heat resistance (solder heat resistance, for example) and excellent conduction reliability in which a small diameter via hole can be formed. RESOLUTION MEANS To provide a manufacturing method of a laminate body, containing: a step of forming onto a supporting body a curable resin composition layer formed from a thermosetting resin composition to obtain a curable resin composition layer with a supporting body; a step of laminating the aforementioned curable resin composition with a supporting body onto a substrate on a curable resin composition layer forming surface side to obtain a pre-cured composite with a supporting body formed from a substrate and a curable resin composition layer with a supporting body; a step of performing a first heating of the aforementioned composite and thermally curing the aforementioned curable resin composition layer to form a cured resin layer to obtain a cured composite with a supporting body formed from a substrate and a cured resin layer with a supporting body; a step of performing hole punching from the aforementioned supporting body side of the aforementioned cured composite with a supporting body to form a via hole in the aforementioned cured resin layer; a step of peeling the aforementioned supporting body from the aforementioned cured composite with a supporting body to obtain a cured composite formed from a substrate and a cured resin layer a step of removing resin residue in the via hole of the aforementioned cured composite; a step of performing a second heating of the aforementioned cured composite; and a step of forming a conductor layer on an inner wall surface of the via hole of the aforementioned cured composite and on the aforementioned cured resin layer.

A wiring substrate includes: a base material; a first through-hole and a second through-hole that are formed in the base material; magnetic material that is filled in the first through-hole; a third through-hole that is formed in the magnetic material; a first plating film that covers an inner wall surface of the third through-hole; and a second plating film that covers an inner wall surface of the second through-hole and the first plating film. The first plating film includes a first electroless plating film that is in contact with the inner wall surface of the third through-hole, and a first electrolytic plating film that is laminated on the first electroless plating film.

A printed circuit board (PCB) includes: a substrate; and a circuit pattern disposed on the substrate, wherein the circuit pattern includes a first seed layer disposed on the substrate and including a nitride, and a metal layer disposed on the first seed layer.