Abstract:
A multi-layer circuit board (10) comprises a liquid crystalline polymer bond ply (12) disposed between two circuit layers (14, 20) wherein the liquid crystalline polymer bond ply (12) is formed by treating a film comprising a liquid crystalline polymer with an amount of heat and pressure effective to produce a liquid crystalline polymer bond ply (12) with an in-plane coefficient of thermal expansion (CTE) of 0 to about 50 ppm/°C and further wherein the multi-layer circuit (10) is formed by lamination at a temperature of 0°C to about 10°C less than the melt temperature of the liquid crystalline polymer.
Abstract:
In this application is disclosed an adhesive film for a multilayer printed wiring board which comprises at least the following Layer A and Layer B in the adjacent position, wherein the thermosetting resin composition constituting the Layer B is a thermosetting resin composition which contains a resin having a lower softening point than the lamination temperature concerned in an amount of not smaller than 10% by weight, and can fill with itself (or resin-fill) the through holes and/or via holes concurrently with being laminated onto a circuit board;
Layer A: A heat-resistant resin layer comprising at least one heat-resistant resin selected from the group consisting of a polyimide, a liquid crystal polymer, an aramid resin and a polyphenylene sulfide and having a thickness of 2 to 30 µm, Layer B: A thermosetting resin composition layer which contains an epoxy resin having at least two epoxy groups in one molecule (Component (a)) and an epoxy curing agent (Component (b)) and is solid at ordinary temperature, with the use of which adhesive film can allows an easy introduction of an insulating layer having excellent mechanical strength at the time of producing a multilayer printed wiring board by a build-up technique, and a multilayer printed wiring board having excellent mechanical strength can, in turn, be provided.
Abstract:
A composite electronic and/or optical substrate including polymeric and ceramic material wherein the composite substrate has a dielectric constant less than 4 and a coefficient of thermal expansion of 8 to 14 ppm/ °C at 100°C. The composite substrate may be either ceramic- filled polymeric material or polymer-filled ceramic material.
Abstract:
The present invention provides a microelectronic assembly wherein a semi-crystalline copolymer adhesive composition (20), preferably provided in the form of a film, is used to electrically interconnect a first circuit pattern (14) on a first substrate (12) to a second circuit pattern (18) on a second substrate (16). The adhesive composition preferably includes a semi-crystalline copolymer comprising polyether and polyamide monomeric units, a tackifier, and conductive particles (22).
Abstract:
There are disclosed a nonwoven reinforcement for a printed wiring base board which nonwoven reinforcement comprises a wet-system nonwoven fabric constituted of thermotropic cystalline polyester fiber having a melting point of 290°C or higher( component A ) and a thermotropic cystalline polyester binder which has a melting point of 290°C or higher and is in the form of a film having holes including at least 5 holes /mm 2 each with an area of opening of 400 to 10000 µm 2 ( component B ), the component A being fixed by the component B; a process for producing the above nonwoven reinforcement; a printed wiring base board produced from the above nonwoven reinforcement; and a printed wiring board produced from the above printed wiring base board. The nonwoven reinforcement and the printed wiring ( base) board are excellent in various performances such as uniformity, dimensional stability, heat resistance and electrical characteristics such as dielectric constasnt and dielectric loss tangent.
Abstract:
A coating layer of a polymer capable of forming an optically anisotropic melt phase is formed by heat-pressing to a base material a film made of the polymer and having a segment orientation ratio of not greater than 1.3 and then separating the film into two halves so as to leave one of the halves on the base material, thereby obtaining a coated material made of the base material and the thin coating layer.
Abstract:
The invention provides a multilayer microelectronic circuit board comprising a laminate of a plurality of circuit layers containing conductive vias (12) within the layers or a combination of conductive vias (12) and conductive wiring patterns (16) on a surface of the layers, said layers comprising a first liquid crystal polymer (10) and, interposed between said circuit layers, a layer of second liquid crystal polymer (21) having a melting point of at least about 10 °C lower than the melting point of said first liquid crystal polymer (10). The boards are produced by stacking a plurality of circuit layer sheets (10) in appropriate electrical alignment such that they are separated by an interposed layer (21) of the second liquid crystal polymer of lower melting point, and heating the stacked polymer sheets under pressure sufficient to bond the sheets or layers into a microelectronic printed circuit board, the temperature of the heating being sufficient to melt the lower melting second polymer but insufficient to melt the polymer present in the circuit layers. The second polymer layer may be interposed as a separate sheet during assembly or may be present as one or two separate surface layers (22) in contact with the higher melting point polymer (23) of the circuit layers.
Abstract:
A composite material and a method for making same are disclosed. A composite article including an electrically and/or thermally insulating substrate and protective layers on each side thereof is particularly disclosed. Said material includes protective layers consisting of fibres of a heat-stable material flocked onto the insulating substrate, and a heat-stable coating resin. The resulting protective layer has improved protective properties, particularly moisture-proofness. The composite material may also be used as a metal layer carrier for forming flexible printed electrical circuits.
Abstract:
A method is provided for forming one or more electrical conductors in a multilayer structure such as a computer component during a punching operation. A conducting sheet (10) is placed in direct contact with a sheet of a deformable dielectric material (12). A punch (8) is used to form a conducting slug (14) from the sheet and to simultaneously transfer the slug into the dielectric material (12). During the transfer operation, a portion of the dielectric material is displaced so as to cause a mechanical interference between the slug and dielectric material.