A power plane structure for a printed circuit board includes a copper layer, and a carbon layer applied directly to a surface of the copper layer. The carbon layer can include graphite or graphene. In additional embodiments, a duplicate power plane structure for a printed circuit board includes two power planes separated by an insulating core, each power plane including a copper layer and a carbon layer applied directly to a surface of the copper layer.

A method for the large-scale production of PCBs including a continuous selective adhesion process for creating printed circuit traces providing input to a production line. A roll of printed circuit traces is produced using rolls of flexible substrate, conductive layer, and conductive layer support by applying adhesive between the rolls of flexible substrate and conductive layer, bringing the rolls together, transferring a circuit pattern onto the flexible substrate, curing the adhesive through non-opaque areas of the circuit pattern, and separating the non-bonded areas. The resulting printed circuit traces are applied from the roll to mounts, and circuit components are applied from a roll to the traces as the mounts move along the line. Additional rolls of printed circuit traces and circuit components may be incorporated, and multi-layer PCBs may be produced. As part of the production line, the finished PCBs may be applied to flat or contoured products.

Various sensors and methods of assembling sensors are described. In some embodiments, the sensor assembly includes a first end, a body portion, and a second end. The first end can include a neck portion and a connector portion and the second end can include a flap, a first component, a neck portion, and a second component. A method is also described for sensor folding. The method can include using a circuit with an attached emitter and a detector that is separated by a portion of the circuit. The method can also include folding the portion of the circuit such that a first fold is created through the emitter and folding the portion of the circuit such that a second fold is created such that the first fold and second fold form an angle.

In a method for producing a wiring circuit board, a conductive pattern is formed using a plating resist formed by photolithography for sequentially moving one photomask in a first direction with respect to a dry film resist to be exposed a plurality of times. The conductive pattern has a conductive intermediate portion which is inclined. The one photomask has a third photo pattern. The third photo pattern includes a first photoline pattern and a second photo line pattern. A first portion of the first photoline pattern coincides with a second portion of the second photoline pattern when projected in the first direction.

A method for milling flex foil includes providing a web (14) of flex foil including a substrate; a first conductive layer arranged on one surface of the substrate; a second conductive layer arranged on an opposite surface of the substrate; a first insulating layer arranged adjacent to the first conductive layer; and a second insulating layer arranged adjacent to the second conductive layer. The method includes dry milling one side of the web using a milling wheel (20-1) and a first cliche pattern (25-1) (including a rotating drum (24-1) and a flexible substrate (26-1)) including raised portions and non-raised portions to selectively remove at least one of the first conductive layer and the first insulating layer. The method includes dry milling an opposite side of the web using a milling wheel (20-2) and a second cliche pattern (25-2) including upper raised portions, lower raised portions and non-raised portions to selectively remove the second insulating layer.

A method and structure for forming conductive structure such as an electric circuit, or a portion of an electric circuit, can include the use of a thermal print head and a ribbon including a carrier and a metal layer. The thermal print head is used to print a first portion of the metal layer onto a sacrificial print medium. The first portion printed has a first pattern, where a second portion having a second pattern remains on the carrier. The first pattern is a reverse image at least a portion of the electric circuit, while the second pattern includes at least a portion of the electric circuit. The second portion having the second pattern can be transferred to a circuit substrate, then used as an electric circuit.

In a method of heat sink attachment, a heat-sink tape includes a plurality of heat sinks and a flexible carrier, and a holder is provided to allow the heat sinks on the moving heat-sink tape to peel from the flexible carrier and attach to a heat-sink mounting area of a moving circuit tape automatically and successively.

A method of connecting a plurality of electronic components to a flexible circuit board comprises: providing a carrier substrate carrying the electronic components, each of the electronic components having at least one electrical contact coated with electrically conductive adhesive; and applying the carrier substrate to the flexible circuit board such that the electronic components are adhered to the flexible circuit board in electrical contact therewith via the conductive adhesive. The electronic components may comprise LEDs and there may be provided one or more optical layers over the flexible circuit board.

A method of making a printed circuit board includes a step of providing a double-sided plate that is an insulating substrate having conductive layers on respective surfaces thereof, a first coating step of coating a first surface of the double-sided plate with a first photosensitive resin film, a second coating step of coating a second surface of the double-sided plate with a second photosensitive resin film, a first exposure step of exposing the photosensitive resin film coating the first surface after the first and second coating steps, and a second exposure step of exposing the photosensitive resin film coating the second surface after the first exposure step, wherein a maximum depth of a depression in an outermost surface of the second photosensitive resin film used in the second exposure step is less than 1.0 μm.

The development of stretchable, mechanically and electrically robust interconnects by printing an elastic, silver-based composite ink onto stretchable fabric. Such interconnects can have conductivity of 3000-4000 S/cm and are durable under cyclic stretching. In serpentine shape, the fabric-based conductor is enhanced in electrical durability. Resistance increases only ˜5 times when cyclically stretched over a thousand times from zero to 30% strain at a rate of 4% strain per second due to the ink permeating the textile structure. The textile fibers are wetted with composite ink to form a conductive, stretchable cladding of the silver particles. The e-textile can realize a fully printed, double-sided electronic system of sensor-textile-interconnect integration. The double-sided e-textile can be used for a surface electromyography (sEMG) system to monitor muscles activities, an electroencephalography (EEG) system to record brain waves, and the like.