A multi-layered circuit board proofed against conductor loss or diminution when heated includes first and second circuit base boards. Each first circuit base board includes a first dielectric layer and a first wiring layer formed thereon and a first stepped paste block as a conductor formed in the first dielectric layer. The first stepped paste block is electrically connected to the first dielectric layer. Each second circuit base board includes a second dielectric layer and a second wiring layer, a second stepped paste block as a conductor is formed in the second dielectric layer. When pressed together for an electrical interconnection, the paste blocks are sealed and thus captive between the first and second circuit base boards.

Lighting systems for use in building interiors, for example, which include a plurality of light modules each having an elongate substrate with a lower surface, and electrical circuitry including a plurality of LED units printed to the lower surface via thick film techniques. Each light module is formed as a single-component, packaged construct for easy installation, and facilitates conductive transfer of heat away from the LEDs for enhanced power efficiency. The light modules may be releasably connected to, and extend from, an elongate spine unit which provides structural support and power input to the light modules and optionally, the system may employ use of metallic components, such as the metallic substrate of a light module, for directly conducting current to power the LED units.

An apparatus includes a substrate and an electronic circuit comprising a plurality of conductive tracts forming a printed litz line on the substrate for distributing a signal therebetween in order to increase effective conductance relative to a single conductive line not divided into tracts. The plurality of conductive tracts may be formed by printing a pattern on the substrate and removing portions of the pattern to leave the plurality of conductive tracts. The removing portions of the pattern may be performed by a removal process such as laser cutting, milling, etching, or masking. For example, the removal may be performed by applying ultrashort laser pulses. The printing may be performed by a jetting process, a spray process, an extrusion process, a dispensing process, and/or other types of processes for applying materials.

A durable but thin-film conductive composition of increased flexibility comprises about 90 parts by weight to about 110 parts by weight of a thermosetting resin, about 900 parts by weight to about 1100 parts by weight of a conductive agent, about 10 parts by weight to about 15 parts by weight of a hardener, and about 0 part by weight to about 50 parts by weight of a thixotropic agent. The disclosure further provides a conductive film formed by heating and curing the conductive composition and a circuit board with several circuit layers joined by the conductive film.

In a preparatory process of a method of manufacturing a multilayer substrate, an insulating substrate is prepared, with a conductor pattern formed only on one surface of the insulating substrate. At that time, the conductor pattern is constituted of the Cu element, a Ni layer is formed on the surface of the conductor pattern that is on the side of the insulating substrate. In a first forming process, a via hole having the conductor pattern as the bottom thereof is formed in the insulating substrate. At that time, the Ni layer that is in the area of the bottom is removed. In a filling process, a conductive paste is filled in the interior of the via hole. In a second forming process, a stacked body is formed by stacking a plurality of the insulating substrates. In a third forming process, the stacked body is heated while being subjected to pressure.

Embodiments and fabrication methods for a printed circuit board are provided. The embodiments include milling a first cavity in a first sub-lam, wherein the first cavity extends partially through the first sub-lam and milling a second cavity in a prepreg layer. The first sub-lam, the prepreg layer, and a material sheet are stacked and laminated to form a composite cavity from the first cavity and the second cavity. The embodiments also include removing from the laminated stack one or more portions of the first sub-lam covering the first cavity to expose the composite cavity. Conductive paste is placed in the composite cavity of the laminated stack and sintered to form one or more thermal pathways in the laminated stack.

A multi-layered circuit board proofed against conductor loss or diminution when heated includes first and second circuit base boards. Each first circuit base board includes a first dielectric layer and a first wiring layer formed thereon and a first stepped paste block as a conductor formed in the first dielectric layer. The first stepped paste block is electrically connected to the first dielectric layer. Each second circuit base board includes a second dielectric layer and a second wiring layer, a second stepped paste block as a conductor is formed in the second dielectric layer. When pressed together for an electrical interconnection, the paste blocks are sealed and thus captive between the first and second circuit base boards.

A fabrication method of a circuit includes drilling holes in a substrate, so as to form a plurality of first opening holes and second opening holes in the substrate. A cover film is attached onto the substrate, so as to cover the first opening holes and the second opening holes. A portion of the cover film covering the first opening holes is removed, so as to expose the first opening holes. The first opening holes are filled.

Apparatus and methods are provided for flexible and stretchable circuits. In an example, a method can include forming a first flexible conductor on a substrate, the first flexible conductor including a first conductive trace surrounded on three sides by a first dielectric, and forming a second flexible conductor on top of the first flexible conductor, the first flexible conductor located between the second flexible conductor and the substrate, the second flexible conductor including a second conductive trace surrounded by a second dielectric.

The present invention provides a method for manufacturing a flexible array substrate. The method includes, first, successively forming an adhesive layer, a passivation layer, a back-side drive circuit, a planarization layer, a flexible backing plate, and a front-side drive circuit and a display circuit, in a stacked arrangement, on a rigid support plate and then peeling off the rigid support plate and the adhesive layer to form a flexible array substrate having a double-sided circuit structure. The entire process requires no steps of peeling, reversing, and then re-attaching of the flexible backing plate so that it is possible to avoid the issues of poor flatness and low yield resulting from improper or wrongful re-attachment of the flexible backing plate and thus, fabrication difficulty of a flexible array substrate having a double-sided circuit structure may be lowered down to thereby improve fabrication yield of the flexible array substrate.