A wiring substrate includes: an insulating substrate comprising a corner constituted by two adjacent surfaces; wiring located continuously across the corner; wherein on at least one of the two adjacent surfaces, a part of the wiring disposed at an edge located at the corner has a thickness larger than a part of the wiring disposed away from the edge.

A wiring board includes a photosensitive insulating layer and a first wiring layer. The photosensitive insulating layer has a hole, a first surface and a second surface opposite to each other. The hole has a first end opening formed in the first surface, a second end opening formed in the second surface, an axis, and a sidewall surrounding the axis. Part of the sidewall extends toward the axis to form at least one annular flange. The first wiring layer is disposed on the first surface and includes a first pad, in which the hole exposes the first pad. There is at least one recessed cavity between the annular flange and the first pad. The minimum width of the annular flange is smaller than the maximum width of the recessed cavity.

A wiring structure and a method for manufacturing the same are provided. The wiring structure includes a conductive structure and at least one conductive through via. The conductive structure includes a plurality of dielectric layers, a plurality of circuit layers in contact with the dielectric layers, and a plurality of dam portions in contact with the dielectric layers. The dam portions are substantially arranged in a row and spaced apart from one another. The conductive through via extends through the dam portions.

A method for producing a printed circuit board is disclosed, In the method, a slot is formed in a substrate having at least three layers with the slot extending through at least two of the layers. The slot has a length and a width with the length being greater than the width. The sidewall of the substrate surrounding the slot is coated with a conductive layer. Then, the conductive layer is separated into at least two segments that are electrically isolated along the side wall of the substrate.

A wiring structure and a method for manufacturing the same are provided. The wiring structure includes a conductive structure and at least one conductive through via. The conductive structure includes a plurality of dielectric layers, a plurality of circuit layers in contact with the dielectric layers, and a plurality of dam portions in contact with the dielectric layers. The dam portions are substantially arranged in a row and spaced apart from one another. The conductive through via extends through the dam portions.

A method of fabricating a substrate having a through via includes: providing a carrier board having a release layer thereon; attaching the substrate onto the carrier board via the release layer; applying a light beam to the substrate to form a first blind hole in the substrate, wherein the first blind hole penetrates a first surface and a second surface of the substrate; performing an enlargement process on the first blind hole to form a second blind hole; forming a through via in the second blind hole; and performing a de-bonding process to release the substrate having a through via from the carrier board.

A printed circuit board includes a plurality of layers including conductive layers separated by dielectric layers; and at least one via configured for solder attachment to a connector lead of a surface mount connector, the at least one via including a conductive element that extends from an upper surface of the printed circuit board through one or more of the plurality of layers, the conductive element having a recess in a surface thereof. The recess is configured to receive a tip portion of the connector lead of the surface mount connector. The printed circuit board may have via patterns including signal vias and ground vias.

A printed circuit board includes a plurality of layers including conductive layers separated by dielectric layers; and at least one via configured for solder attachment to a connector lead of a surface mount connector, the at least one via including a conductive element that extends from an upper surface of the printed circuit board through one or more of the plurality of layers, the conductive element having a recess in a surface thereof. The recess is configured to receive a tip portion of the connector lead of the surface mount connector. The printed circuit board may have via patterns including signal vias and ground vias.

A wiring board includes a photosensitive insulating layer and a first wiring layer. The photosensitive insulating layer has a hole, a first surface and a second surface opposite to each other. The hole has a first end opening formed in the first surface, a second end opening formed in the second surface, an axis, and a sidewall surrounding the axis. Part of the sidewall extends toward the axis to form at least one annular flange. The first wiring layer is disposed on the first surface and includes a first pad, in which the hole exposes the first pad. There is at least one recessed cavity between the annular flange and the first pad. The minimum width of the annular flange is smaller than the maximum width of the recessed cavity.

Methods for producing a printed circuit board and printed circuit boards are disclosed, including a method in which a slot is formed in a substrate, the substrate having at least three layers with the slot extending through at least two of the layers. The slot has a length and a width with the length being greater than the width. The sidewall of the substrate surrounding the slot is coated with a conductive layer. The conductive layer is separated into at least two segments that are electrically isolated along the side wall of the substrate.