Abstract: Materials and construction for a tamper indicating radio frequency identification (RFID) label are provided to permit the destruction of the label or its properties in the event of attempts to remove the label from a surface to which it has been applied. An adhesion modifying coating is applied to a label surface or portions thereof to affect the relative adhesion strengths between different layers or areas of the label. The adhesion modifying coating can be applied in selected patterns to achieve differential adhesion strengths and resulting differential separation of the label from a surface on which it has been applied.

Abstract: A novel process is provided for the high speed fabrication of flexible printed circuit boards in continuous roll form and at a cost which is substantially less than the cost of existing fabrication processes. A web of substrate material is supplied from a roll and one or both surfaces are sputter coated with a tie-coat of Monel or chrome and a copper seed layer. The tie-coat is typically of a thickness of about 50-300 angstroms, and the copper seed layer has a thickness of about 200-4000 angstroms. Plated through holes are provided for double sided printed circuit boards, the holes being provided by laser or other suitable drilling equipment in an intended pattern on the substrate. A plating mask is provided with a negative image to allow subsequent selective electrodeposition of copper onto the unmasked areas of the substrate surfaces. The web is then passed through a continuous copper plating cell which provides a plate-up of copper on the unmasked areas of the seed layer.

Abstract: A flat ribbon cable having a controlled impedance and suitable for use at high data rates. The ribbon cable includes a plurality of conductors arranged side-by-side within an insulating material. The conductors include a first portion at each end having a generally circular cross-section, a center portion of generally rectangular cross-section in which the width is greater than the height and a transition portion at each end between the first portion and the second portion. A shield is disposed over selected ones of the plurality of conductors on at least one side of the ribbon cable. A drain wire is provided that is conductively coupled to the shield and may be disposed between the shield and insulating material. The drain wire is disposed over one of the conductors and may be conductively coupled to the conductor via use of a single contact of an insulation displacement connector that engages both the drain wire and the respective conductor.

Abstract: A flat ribbon cable having a controlled impedance and suitable for use at high data rates. The ribbon cable includes a plurality of conductors arranged side-by-side within an insulating material. The conductors include a first portion at each end having a generally circular cross-section, a center portion of generally rectangular cross-section in which the width is greater than the height and a transition portion at each end between the first portion and the second portion. A shield is disposed over selected ones of the plurality of conductors on at least one side of the ribbon cable. A drain wire is provided that is conductively coupled to the shield and may be disposed between the shield and insulating material. The drain wire is disposed over one of the conductors and may be conductively coupled to the conductor via use of a single contact of an insulation displacement connector that engages both the drain wire and the respective conductor.

Abstract: A flat multi-conductor cable and a method for manufacturing such a cable to maintain consistent spacing between adjacent conductors. A dielectric film is laminated to both sides of a plurality of conductors, such as flat copper conductors. The film is heated to cause the film to flow around and adhere to the conductors. A jacket is extruded around the dielectric film to form a jacketed multi-conductor cable. A conductive shield may be applied over the dielectric film prior to the extrusion of the cable jacket. The conductive shield may be conductively coupled to one or more of the conductors by dimpling the shield over the respective conductors or by a laser ablation technique.

Abstract: A process for providing bond enhancement and an etch resist for a printed circuit board is provided. A sheet comprising at least a layer of copper is immerses in a first immersion tin solution comprising a tin metal and a complexing agent in an acidic medium for a time sufficient to deposit a first heavy tin deposit on the sheet. The sheet is then immersed in a second immersion tin solution comprising stannous tin ions and stannic tin ions and a complexing agent in an acidic medium for a time sufficient to deposit a second thin tin deposit on the sheet. The second thin tin deposit has a thickness less than a thickness of the first heavy tin deposit. A rough surface texture providing mechanical adhesion sites results. The board is then treated with a coupling agent, such as silane, for enhanced bonding to a subsequent epoxy or other polymer prepreg. Additionally, the first heavy tin deposit may serve as an etch resist in subsequent fabrication of the provided circuit board.

Abstract: In a rigid/flex circuit board and fabricating process, patterns of electrical traces are formed by etching conductive layers on outer surfaces of a flexible multi-layer circuit structure. A protective barrier material is deposited on the etched traces using an "electroless" process, such as immersion of the flexible circuit board in an aqueous solution containing ionic tin. The protective barrier material adheres to and encapsulates the copper traces. An outer circuit structure including a bondfilm of epoxy-impregnated fiberglass ("prepreg" bondfilm) and a copper foil layer is laminated onto the flexible circuit structure. The prepreg bondfilm has a window area removed by routing or an equivalent process prior to being laminated to the flexible structure. The window area defines a flex area of the rigid/flex circuit board that will be relatively flexible.

Abstract: A printed circuit board and method of manufacture thereof is disclosed. The printed circuit board includes a first substrate provided from a conductive layer having disposed on a first surface thereof a cured adhesive layer, A semi-cured adhesive layer is then disposed over the cured adhesive layer and a second substrate is disposed against the semi-cured adhesive layer.

Abstract: A printed circuit assembly includes a rigidizer having first and second opposing surfaces, a silicone bonding agent disposed over a first surface of the rigidizer, a flex circuit having first and second opposing surfaces with a first surface of the flex circuit disposed over the bonding agent, and a silicone covercoat disposed over selected portions of the second surface of the flex circuit.

Abstract: A method of depositing a conductive material on a surface of a printed circuit board, includes the steps of chemically treating at least a portion of a surface of the printed circuit board, disposing a resist layer over the chemically treated surface, depositing a conductive layer in the areas which are not covered by the resist, stripping the resist from the surface of the printed circuit board, and cleaning exposed chemically treated surfaces of the printed circuit board to remove contaminants from the surface of the printed circuit board which were introduced in the chemically treating step.

Abstract: A printed circuit board and method of manufacture thereof is disclosed. The printed circuit board includes a first substrate provided from a conductive layer having disposed on a first surface thereof a cured adhesive layer. A semi-cured adhesive layer is then disposed over the cured adhesive layer and a second substrate is disposed against the semi-cured adhesive layer.

Abstract: A flexible circuit board providing the dual benefits of flexibility and shielding against incidental radiation. The flexible, shielded circuit board includes a number of electrical conductors disposed in a substrate, substantially parallel to opposing surfaces of the substrate. Electrical shield layers in the form of a mesh or grid are disposed on the substrate surfaces and are preferably formed by screen printing a conductive layer on each side of the substrate. A repeating pattern of shield conductors, shield conductor vertices, and voids in the shield layer through which the substrate is exposed is thus created on either side of the substrate.

Abstract: A method of fabricating a multilayer circuit board having rigid and flexible sections using Z-axis laser routing. A rigid superstructure is provided for lamination to a flexible circuit substrate, wherein the superstructure includes specially configured strips of laser reflective material, disposed on the laminating surface thereof, defining the boundary between the rigid and flexible sections of the multilayer circuit board. In subsequent processing, a beam of laser energy is directed through the rigid superstructure, along the Z-axis thereof, superjacent to each strip of laser reflective material, thereby cutting through the material of the superstructure creating a laser routed channel which forms an interface between the rigid and flexible sections of the finished multilayer circuit board.

Abstract: A narrow-pitch flat cable connector for use in connection of flat cables to printed circuit boards or other substrates includes wireform or prestamped female contacts on the same narrow pitch as that of the cable conductors and a connector housing with contact-receiving slots on the same narrow pitch as that of the cable conductors. The female contacts have U-shaped forward portions and in one embodiment are mounted in staggered offset relationship to the printed circuit board to present contacts at the same narrow pitch established by the narrow pitch of the conductors in the cable. The cable is terminated with a connector housing having a lateral cable insertion channel and vertical pairs of contact-receiving slots communicating with the cable insertion channel and aligned with the conductors of the cable.

Abstract: A flat embedded-shield multiconductor signal transmission cable includes an embedded conformal shield interposed between adjacent conductors to significantly reduce cross-talk by as much as several orders of magnitude over conventional techniques. The shield is forced to a shape in which it is interposed between adjacent conductors by pinch rolling a sandwich of the conductors, insulation and shield between heated rollers, in which the top and bottom sets of conductors are forced inwardly to lie one beside the other with the shield in between. Uniform termination impedance is achieved because the embedded shield is protected during cable stripping. In an alternative embodiment, external shielding may be utilized to completely circumferentially surround the conductors. For improved pitch control, both heated pinch rollers are identical and are provided with resilient surfaces.