Abstract: A composite material useful for the manufacture of a circuit has a support layer, a metal foil layer having opposing first and second sides and a thickness of 15 microns or less and a release layer effective to facilitate separation of the metal foil layer from the support layer, the release layer disposed between and contacting both the support layer and the metal foil layer. A reactive element containing layer, which may be the support layer, effective to react with gaseous elements or compounds to form thermally stable compounds contacts the release layer. The composite material is preferably subjected to a low temperature heat treatment. The combination of the low temperature heat treatment and the reactive element containing layer results in reduced defects including blisters in the copper foil during subsequent processing.

Abstract: A copper foil for lamination to a dielectric substrate is coated with a laser ablation inhibiting layer having an average surface roughness (Rz) of less than 1.0 micron and an average nodule height of less than 1.2 micron that is effective to provide a lamination peel strength to FR-4 of at least 4.5 pounds per inch. The coated foil further has a reflectivity value of at least 40. The coated foil is typically laminated to a dielectric substrate, such as glass reinforced epoxy or polyimide and imaged into a plurality of circuit traces. Blind vias may be drilled through the dielectric terminating at an interface between the foil and the dielectric. The coated foil of the invention resists laser ablation, thereby resisting piercing of the foil by the laser during drilling.

Abstract: The present invention is directed to a coated substrate, comprising: an antitarnish layer deposited on a substrate in an amount effective to prevent tarnishing of said coated substrate; and an outer layer deposited onto said antitarnish layer, said outer layer comprising tin or tin alloys having at least 50% by weight tin. The present invention is also directed to coated substrates having a concentration gradient of antitarnish agent diffused into the coating, as well as methods of forming such coated substrates.

Abstract: A composite material, comprising a carrier strip the carrier strip comprising a first side the first side comprising a substantially uniform roughness, an electrolytically deposited copper foil layer having opposing first and second sides and a thickness of from 0.1 micron to 15 microns and the entire metal foil layer thickness having been deposited from a copper containing alkaline electrolyte, and a release layer effective to facilitate separation of the metal foil layer from the carrier strip disposed between and contacting both the first side of the carrier strip and the second side of the metal foil layer.

Abstract: The present invention is directed to an aqueous, antitarnish and adhesion promoting treatment composition, comprising: zinc ions; metal ions selected from the group consisting of tungsten ions, molybdenum ions, cobalt ions, nickel ions, zirconium ions, titanium ions, manganese ions, vanadium ions, iron ions, tin ions, indium ions, silver ions, and combinations thereof; and optionally, an electrolyte that does not contain potassium or sodium ions; wherein the treatment composition is substantially free of chromium, and wherein the treatment composition forms a coating on a substrate or material that enhances adhesion of a polymer to the material. The present invention is also directed to materials coated with the above treatment composition, and methods of coating materials using the above composition.

Abstract: A copper foil for lamination to a dielectric substrate iscoated with a laser ablation inhibiting layer having an average surface roughness of less than 0.7 micron and an average nodule height of less than 0.75 micron that is effective to provide a lamination peel strength to FR-4 of at least 4.5 pounds per inch. The foil is typically laminated to a dielectric substrate, such as glass reinforced epoxy or polyimide and imaged into a plurality of circuit traces. Blind vias may be drilled through the dielectric terminating at an interface between the foil and the dielectric. The coated foil of the invention resists laser ablation, thereby resisting piercing of the foil by the laser during drilling.

Abstract: A coated electrically conductive substrate has particular utility where there are multiple closely spaced leads and tin whiskers constitute a potential short circuit. Such substrates include leadframes, terminal pins and circuit traces such as on printed circuit boards and flexible circuits. This electrically conductive substrate has a plurality of leads separated by a distance capable of bridging by a tin whisker, a silver or silver-base alloy layer coating at least one surface of at least one of the plurality of leads, and a fine grain tin or tin-base alloy layer directly coating said silver layer. An alternative coated electrically conductive substrate has particular utility where debris from fretting wear may oxidize and increase electrical resistivity, such an in a connector assembly. This electrically conductive substrate has a barrier layer deposited on the substrate that is effective to inhibit diffusion of constituents the substrate into a plurality of subsequently deposited layers.

Abstract: A composite material useful for the manufacture of a circuit has a support layer, a metal foil layer having opposing first and second sides and a thickness of 15 microns or less and a release layer effective to facilitate separation of the metal foil layer from the support layer, the release layer disposed between and contacting both the support layer and the metal foil layer. A reactive element containing layer, which may be the support layer, effective to react with gaseous elements or compounds to form thermally stable compounds contacts the release layer. The composite material is preferably subjected to a low temperature heat treatment. The combination of the low temperature heat treatment and the reactive element containing layer results in reduced defects including blisters in the copper foil during subsequent processing.

Abstract: The present invention is directed to an aqueous, antitarnish and adhesion promoting treatment composition, comprising: zinc ions; metal ions selected from the group consisting of tungsten ions, molybdenum ions, cobalt ions, nickel ions, zirconium ions, titanium ions, manganese ions, vanadium ions, iron ions, tin ions, indium ions, silver ions, and combinations thereof; and optionally, an electrolyte that does not contain potassium or sodium ions; wherein the treatment composition is substantially free of chromium, and wherein the treatment composition forms a coating on a substrate or material that enhances adhesion of a polymer to the material. The present invention is also directed to materials coated with the above treatment composition, and methods of coating materials using the above composition.

Abstract: The present invention is directed to a coated substrate, comprising: an antitarnish layer deposited on a substrate in an amount effective to prevent tarnishing of said coated substrate; and an outer layer deposited onto said antitarnish layer, said outer layer comprising tin or tin alloys having at least 50% by weight tin. The present invention is also directed to coated substrates having a concentration gradient of antitarnish agent diffused into the coating, as well as methods of forming such coated substrates.

Abstract: A composite material includes a structural carrier layer and a relatively thin metal foil layer separated by a release layer. The release layer, that may be an admixture of a metal such as nickel or chromium and a non-metal such as chromium oxide, nickel oxide, chromium phosphate or nickel phosphate, provides a peel strength for the metal foil layer from the carrier strip that is typically on the order of 0.1 pound per inch to 2 pounds per inch. This provides sufficient adhesion to prevent premature separation of the metal foil layer from the carrier layer, but easy removal of the carrier layer when desired. Typically, the metal foil layer is subsequently bonded to a dielectric and the carrier layer then removed. The metal foil layer is then imaged into circuit features in the manufacture of printed circuit boards and flexible circuits.

Abstract: A composite material includes a structural carrier layer and a relatively thin metal foil layer separated by a release layer. The release layer, that may be an admixture of a metal such as nickel or chromium and a non-metal such as chromium oxide, nickel oxide, chromium phosphate or nickel phosphate, provides a peel strength for the metal foil layer from the carrier strip that is typically on the order of 0.1 pound per inch to 2 pounds per inch. This provides sufficient adhesion to prevent premature separation of the metal foil layer from the carrier layer, but easy removal of the carrier layer when desired. Typically, the metal foil layer is subsequently bonded to a dielectric and the carrier layer then removed. The metal foil layer is then imaged into circuit features in the manufacture of printed circuit boards and flexible circuits.

Abstract: A composite material includes a structural carrier layer and a relatively thin metal foil layer separated by a release layer. The release layer, that may be an admixture of a metal such as nickel or chromium and a non-metal such as chromium oxide, nickel oxide, chromium phosphate or nickel phosphate, provides a peel strength for the metal foil layer from the carrier strip that is typically on the order of 0.1 pound per inch to 2 pounds per inch. This provides sufficient adhesion to prevent premature separation of the metal foil layer from the carrier layer, but easy removal of the carrier layer when desired. Typically, the metal foil layer is subsequently bonded to a dielectric and the carrier layer then removed. The metal foil layer is then imaged into circuit features in the manufacture of printed circuit boards and flexible circuits.

Abstract: A tin coated electrical or electronic component has enhanced resistance to oxidation and tarnishing as well a smaller increase in contact resistance when exposed to elevated temperatures. These benefits are achieved by depositing a relatively thin, on the order of 5-50 angstroms thick, layer of zinc on the tin coating prior to heating. A subsequent step of heating the sample to a temperature and time effective to convert all free tin to an intermetallic imparts the additional advantage of reducing the coefficient of friction.

Abstract: A method of introducing an anti-tarnish agent into the matrix of a tin coating to reduce oxidation and/or yellowing of the tin coating. The agent is preferably zinc, indium or phosphorous and can be deposited in a molten form to alloy with the existing tin coating. Alternatively, the existing tin coating may be exposed to a chemical bath including the agent and later heated to reflow the tin coating and agent thereby incorporating the agent into the matrix of the tin coating.

Abstract: An electrical conductor has a copper base substrate coated with a tin base coating layer. To inhibit the diffusion of copper from the substrate into the coating layer and the consequential formation of a brittle tin/copper intermetallic, a barrier layer is interposed between the substrate and the coating layer. This barrier layer contains from 20% to 40%, by weight, of nickel and is preferably predominantly comprised of copper. In one embodiment, an intermetallic layer selected from the group (Cu--Ni).sub.3 Sn, (Cu--Ni).sub.6 Sn.sub.5, Cu.sub.3 Sn, Cu.sub.6 Sn.sub.5 is disposed between the barrier layer and the tin base coating layer.

Abstract: There it is disclosed a chemical treatment for copper foil which imparts a dark brown to black color to the foil and improves the bond strength of the foil to a dielectric substrate without detrimentally changing the etching characteristics of the foil. The treatment includes depositing a nodular copper/nickel alloy layer on a surface of the foil. These nodules are 55% to 95% by weight copper and are electrolytically deposited using a pulse power controller.

Abstract: An electrical conductor has a copper base substrate coated with a tin base coating layer. To inhibit the diffusion of copper from the substrate into the coating layer and the consequential formation of a brittle tin/copper intermetallic, a barrier layer is interposed between the substrate and the coating layer. This barrier layer contains from 10% to 70%, by weight, of nickel and is preferably predominantly comprised of copper. In one embodiment, an intermetallic layer selected from the group (Cu--Ni).sub.3 Sn, (Cu--Ni).sub.6 Sn.sub.5, Cu.sub.3 Sn, Cu.sub.6 Sn.sub.5 is disposed between the barrier layer and the tin base coating layer.

Abstract: A flexible circuit to interconnect two components of an electrical device is formed with a flexible polymeric substrate. A copper alloy is laminated to the flexible substrate. This copper alloy is processed to have relatively high strength, an ultimate tensile strength in excess of about 80 ksi, by either alloying additions, by processing or by a combination of the two. When such an alloy is laminated to the polymeric substrate, the resultant flexible circuit has improved (more cycles to failure) dynamic fatigue performance when compared to both pure copper and dilute copper alloys.

Abstract: There is provided a method of treating a copper or copper alloy substrate to provide improved resistance to both oxidation and to chemical attack. The substrate is immersed in an aqueous solution containing both chromium (VI) ion and phosphate ions. The treatment is particularly effective for protecting imaged printed circuit boards during storage, handling and use.