Systems and techniques are provided for trench cutting with laser machining. A laminate material including a conductive layer and a non-conductive layer may be cut with a first cut using a UV-laser. The cutting of a second cut, using the UV-laser, may be started at a top electrode of the non-conductive layer based on the location of the first cut, wherein the second cut is wider than the first cut. The cutting of the second cut may be stopped partially though the non-conductive layer. The stopping of the cutting of the second cut partially though the non-conductive layer may include stopping the cutting of the second cut before cutting a bottom electrode of the non-conductive layer.

A method for manufacturing a wiring board that has a rewiring layer on a surface thereof includes forming an insulating layer on a core substrate, forming a groove, in which a wiring layer of a circuit pattern is to be provided, on the insulating layer, forming a metal seed layer on an exposed face of the insulating layer on which the groove is formed, electrodepositing metal, which is to form the wiring layer, by plating to fill the groove with the metal to form a metal layer on the seed layer, machining the metal layer by a cutting tool to remove the metal layer up to a position not reaching the top of the insulating layer, and performing etching or a CMP process to expose the top of the insulating layer thereby to form the wiring layer in the groove and flatten an exposed face of the wiring layer.

A rigid flexible board includes: a substrate that has flexibility and electric insulation; a protective layer formed at a central portion of each of opposite surfaces of the substrate; and a plurality of core layers partially covering the protective layer and formed at a circumferential edge of each of the opposite surfaces of the substrate; wherein a gap is formed close to a center of the substrate in a thickness direction thereof between the core layers and the protective layer.

A wiring substrate includes a first wiring layer with a wiring pattern and a metal foil. A first insulating layer includes a first through hole having a first end facing the metal foil and a second end. A second wiring layer includes a first opening having a diameter smaller than the second end. A second insulating layer includes a second through hole having a third end facing the wiring pattern and a fourth end. A third wiring layer includes a second opening having a diameter smaller than the fourth end. A first via is filled in the first opening, the first through hole, and a first recess, in the metal foil, having a diameter greater than the first end. A second via is filled in the second opening, the second through hole, and a second recess, in the wiring pattern, having a diameter greater than the third end.

The present invention is used to carry out repairs on a defective circuit of a circuit board, with two conducting portions and a defective portion therebetween. The operating method comprises: using a laser light source of a single laser dual optical circuit repair member of a single laser repair module to emit an initial laser beam toward an energy distribution unit, thereby producing a first laser beam and a second laser beam; using a switching unit to mask the second laser beam, thereby transmitting the first laser beam toward the circuit board, to transform the defective portion into a sintered portion; and using the switching unit to mask the first laser beam, thereby transmitting the second laser beam toward the circuit board, thereby deflashing of the sintered portion, causing sintered sides of the sintered portion to be flush with two conducting sides of the two conducting portions.