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: In one aspect, a copper foil for lamination to a dielectric substrate includes a layer deposited on a surface of the copper foil. The layer is formed from chromium and zinc ions or oxides and is treated with an aqueous solution containing at least 0.5% silane. In another aspect, a peel strength enhancement coating is disposed between a copper foil laminate and a dielectric substrate. The peel strength enhancement coating comprises a metal and metal oxide mixture containing a metal selected from groups 5B, 6B, and 7B of the periodic table of the elements. The effective thickness of the peel strength enhancement coating is that thickness capable of providing less than or equal to 10% loss of peel strength, when measured in accordance with IPC-TM-650 Method 2.4.8.5 using a ? inch wide test specimen, after being immersed in 4N HCl at about 60° C. for 6 hours.

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 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 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: In one aspect, a copper foil for lamination to a dielectric substrate includes a layer deposited on a surface of the copper foil. The layer is formed from chromium and zinc ions or oxides and is treated with an aqueous solution containing at least 0.5% silane. In another aspect, a peel strength enhancement coating is disposed between a copper foil laminate and a dielectric substrate. The peel strength enhancement coating comprises a metal and metal oxide mixture containing a metal selected from groups 5B, 6B, and 7B of the periodic table of the elements. The effective thickness of the peel strength enhancement coating is that thickness capable of providing less than or equal to 10% loss of peel strength, when measured in accordance with IPC-TM-650 Method 2.4.8.5 using a ⅛ inch wide test specimen, after being immersed in 4N HCl at about 60° C. for 6 hours.

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: 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: 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 release force 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. The metal foil layer may be electrolytically formed copper having a low height profile, on the order of 0.5 micron to 2.7 microns, bond strength enhancing agent coating a side of the metal foil layer. The enhanced surface is subsequently bonded to a dielectric and the carrier layer then removed.

Abstract: A copper alloy having improved resistance to stress relaxation contains controlled additions of iron, phosphorous and magnesium. Free magnesium, in solid solution with the copper, increases the alloy's resistance to stress relaxation. Copper alloys of the invention retain at least 70% of the initial stress following exposure to a temperature of 105.degree. C. for 3000 hours, making the alloys particulary useful for electrical connector components.

Abstract: A copper alloy achieves high electrical conductivity, in excess of 70% IACS; high strength, ultimate tensile strength in excess of 75 ksi; good surface cosmetics; and good stampability, above 25% break, by controlled additions of magnesium, iron and phosphorous. There is a critical iron content to achieve both good stampability and high electrical conductivity and a critical phosphorous content to achieve high strength and relatively small metal phosphide particles. There is further, a critical relationship between the amount of iron and phosphorous. An additions of magnesium, in amounts of more than 0.03%, broadens the effective ratio of iron to phosphorous, widening the composition box of the alloys of the invention.

Abstract: A copper alloy having improved resistance to stress relaxation contains controlled additions of iron, phosphorous and magnesium. Free magnesium, in solid solution with the copper, increases the alloy's resistance to stress relaxation. Copper alloys of the invention retain at least 70% of the initial stress following exposure to a temperature of 105.degree. C. for 3000 hours, making the alloys particularly useful for electrical connector components.

Abstract: There is provided a composite material particularly suited for electrical and electronic applications having a metallic core with a desired surface finish. An acicular superficial coating layer having an apparent thickness of less than 275 angstroms is adjacent to at least a portion of the metallic core. The superficial coating layer is removable from the metallic core without appreciable change to the metallic core surface finish.

Abstract: The present invention relates to composites having excellent combinations of bending strength, electrical conductivity, stress relaxation in bending and bend formability and having particular utility in electrical connector applications. The composites of the present invention have a core formed from a copper base alloy having an electrical conductivity of at least about 80% IACS and a clad formed from a copper-nickel alloy containing more than about 30% by weight nickel. Preferred composites are triclad composites formed from copper alloy C151 and MONEL 400 and having clad layer thicknesses of at least about 10%, most preferably at least about 20%, of the overall composite thickness.

Abstract: The present invention relates to composites having excellent combinations of bending strength, electrical conductivity, stress relaxation in bending and bend formability and having particular utility in electrical connector applications. The composites of the present invention have a core formed from a copper base alloy having an electrical conductivity of at least about 80% IACS and a clad formed from a copper-nickel alloy containing more than about 30% by weight nickel. Preferred composites are triclad composites formed from copper alloy C151 and MONEL 400 and having clad layer thicknesses of at least about 10%, most preferably at least about 20%, of the overall composite thickness.

Abstract: A process for rolling a metal strip for reducing its thickness and for increasing the maximum reduction attainable per pass using a cooperative type rolling mill comprises applying differential separating forces to the metal strip without changing the magnitude of the compressive force applied to the rolls. By doing this, the maximum strip tension and the forward tension required to pull the strip through the mill may be reduced. The maximum strip tension and the required forward tension force may further be reduced by driving at least one work roll at a desired value of torque as well as applying differential separating forces. The cooperative type rolling mill uses a roll spacing arrangement to space at least some of the rolls for reducing the separating force applied to the metal strip at selected roll bites. In addition, individual drive motors to drive the work rolls at desired torque values may be utilized.

Abstract: A process for forming a composite material from a core material having a first yield strength and a clad material having a second yield strength comprises passing the materials through at least one roll bite formed by at least two rolls rotating at different speeds relative to each other. A bond is formed between the core and clad materials by causing a reduction in the thickness of the materials as they pass through the at least one roll bite. The amount of reduction and the compressive force magnitude required to effect the bond is minimized. The process also includes applying back tension forces to the materials. In a preferred embodiment, different back tension forces are applied to the core and clad materials.

Abstract: A duplex rolling process and apparatus for working a metal or alloy subject to the formation of strain induced martensite. The metal or alloy is first worked at an elevated temperature wherein the formation of strain induced martensite is substantially suppressed or eliminated. The metal or alloy is then worked at a lower temperature wherein the formation of strain induced martensite is promoted whereby working is carried out more efficiently.

Abstract: An apparatus and process for operating a rolling mill having at least two rolls rotating at different speeds to produce a continuous strip material having a substantially constant final thickness comprises a mechanism for controlling the magnitude of the compressive force between the rolls in response to the ratio of the incoming strip speed to the outgoing strip speed. A mechanism is provided for comparing the ratio of the strip speeds to a ratio of the roll speeds and for adjusting the compressive force magnitude until the two speed ratios are substantially equal. In this manner, the amount of off-stage strip material produced during mill start-up is reduced and process stability and gage control during steady state operation is enhanced.

Abstract: This invention relates to a rolling mill apparatus and process which utilizes the creation of a differential friction force in at least the most downstream one of a plurality of roll bites for a variety of purposes. In a first embodiment, a differential friction force is created at the most downstream roll bite for reducing the maximum strip tension and forward strip tension thereby increasing the maximum attainable reduction in strip thickness per pass and reducing the size of the recoiler used for applying the forward tension. In a second embodiment, differential friction forces are created at the most upstream roll bite and the most downstream roll bite for increasing strip tension at all of the roll bites while decreasing the separating force required to obtain given strip reductions without increasing the maximum strip tension.