Abstract: An electrically optimized and structurally protected micro via structure for high speed signals in multilayer interconnection substrates is provided. The via structure eliminates the overlap of a contact with the reference planes to thereby reduce the via capacitance and thus, the via impedance mismatch in the via structure. As a result, the via structure is electrically optimized. The via structure further comprises one or more floating support members placed in close proximity to the via within a via clearance area between the via and the reference planes. The floating support members are “floating” in the sense that they are not in electrical contact with either the via or the reference planes. Thus, they are not provided for purposes of signal propagation but only for structural support. The floating support members may be connected to one another by way of one or more microvia structures.

Abstract: Generally provided is a circuit assembly construction for controlling impedance in an electronic package. A large scale, parallel-plate capacitor includes two electrodes separated by a dielectric material. The electrodes serve as reference voltage planes for the electronic package. At least one of the electrodes is patterned such that both electrodes are accessible from a common side of the capacitor. The capacitor is positioned with a first electrode mounted adjacent to an interconnect circuit portion of the electronic package. An electronic device portion of the electronic package is electrically connected, directly or indirectly, to one or more of the electrodes of the capacitor.

Abstract: An electrically optimized and structurally protected micro via structure for high speed signals in multilayer interconnection substrates is provided. The via structure eliminates the overlap of a contact with the reference planes to thereby reduce the via capacitance and thus, the via impedance mismatch in the via structure. As a result, the via structure is electrically optimized. The via structure further comprises one or more floating support members placed in close proximity to the via within a via clearance area between the via and the reference planes. The floating support members are “floating” in the sense that they are not in electrical contact with either the via or the reference planes. Thus, they are not provided for purposes of signal propagation but only for structural support. The floating support members may be connected to one another by way of one or more microvia structures.

Abstract: An electronic package including a conductive trace layer having a first side and a second side. The conductive trace layer is patterned to define a plurality of interconnect pads. A flexible dielectric substrate is mounted on the first side of the conductive trace layer. A flexible capacitor including a first conductive layer, a second conductive layer and a layer of dielectric material disposed between the first and the second conductive layers is mounted with the first conductive layer adjacent to the second side of the conductive trace layer. A plurality of interconnect regions extend through the first conductive layer and the dielectric material layer of the capacitor. An interconnect member is connected between each one of the conductive layers of the capacitor and a corresponding set of the interconnect pads.

Abstract: An electronic package including a conductive trace layer having a first side and a second side. The conductive trace layer is patterned to define a plurality of interconnect pads. A flexible dielectric substrate is mounted on the first side of the conductive trace layer. A flexible capacitor including a first conductive layer, a second conductive layer and a layer of dielectric material disposed between the first and the second conductive layers is mounted with the first conductive layer adjacent to the second side of the conductive trace layer. A plurality of interconnect regions extend through the first conductive layer and the dielectric material layer of the capacitor. An interconnect member is connected between each one of the conductive layers of the capacitor and a corresponding set of the interconnect pads.

Abstract: A low-cost integrated circuit package is provided for packaging integrated circuits. In preferred embodiments, the package comprises a flexible circuit that is laminated to a stiffener using a dielectric adhesive, with the conductive traces on the flexible circuit facing toward the stiffener but separated therefrom by the adhesive. The conductive traces include an array of flip-chip attachment pads. A window is formed in the stiffener over the attachment pad array, such as by etching. The adhesive is then removed over the attachment pads by laser ablation, but left in place between the pads, thus forming a flip-chip attachment site. In preferred embodiments, this invention eliminates the need for high-resolution patterned adhesive, and it also eliminates the need for application of a solder mask at the flip-chip attachment site, because the remaining adhesive performs the solder mask function of preventing bridging between attachment pads.

Abstract: The invention provides a process for fabricating a flexible printed circuit with at least one etched or plated feature on each major surface of said flexible circuit, comprising the steps of providing an input material with two major surfaces, including a dielectric substrate and at least one conductive base layer, laminating a photoresist with a cover sheet onto at least one major surface of the input material, and printing an image onto the cover sheet or removing the coversheet and printing the image onto the photoresist directly.

Abstract: A low-cost integrated circuit package is provided for packaging integrated circuits. In preferred embodiments, the package comprises a flexible circuit that is laminated to a stiffener using a dielectric adhesive, with the conductive traces on the flexible circuit facing toward the stiffener but separated therefrom by the adhesive. The conductive traces include an array of flip-chip attachment pads. A window is formed in the stiffener over the attachment pad array, such as by etching. The adhesive is then removed over the attachment pads by laser ablation, but left in place between the pads, thus forming a flip-chip attachment site. In preferred embodiments, this invention eliminates the need for high-resolution patterned adhesive, and it also eliminates the need for application of a solder mask at the flip-chip attachment site, because the remaining adhesive performs the solder mask function of preventing bridging between attachment pads.