Abstract: Composite materials for electronic packages are disclosed. The composite materials comprise a core layer and first and second cladding layers. The core and cladding layer compositions and thicknesses are selected to maximize thermal and electrical conductivity and to minimize the coefficient of thermal expansion of the composite. The composite material may be employed to fashion the package base, the leadframe, a heat spreader or combinations thereof. In one embodiment, a portion of the first cladding layer is removed so that an electronic device may be mounted directly to a high thermal conductivity core.

Abstract: There is provided a leadframe assembly for supporting a hybrid circuit. The hybrid circuit is supported by either the base of an electronic package or by a die attach paddle and electrically interconnected to a leadframe by wire bonds. A plurality of semiconductor devices are mounted on the assembly and supported by either metallization pads formed on the hybrid circuit, a dielectric layer of the hybrid circuit, a die attach paddle, a metallic package component or combinations thereof.

Abstract: Machinable alpha beta brass having a reduced lead concentration is claimed. The alloy contains bismuth to improve machinability. Either a portion of the zinc is replaced with aluminum, silicon or tin, or a portion of the copper is replaced with iron, nickel or manganese.

Abstract: There is provided an electronic package assembly having a leadframe and buffer bonded to a metallic base. To reduce the stress generated by the coefficient of thermal expansion mismatch, the buffer is mounted on a pedestal. The cross sectional area of the pedestal is less than that of the buffer, such that the at least a portion of the buffer overhangs the pedestal.

Abstract: Machinable alpha beta brass having a reduced lead concentration is claimed. The alloy contains bismuth to improve machinability. Either a portion of the zinc is replaced with aluminum, silicon or tin, or a portion of the copper is replaced with iron, nickel or manganese.

Abstract: A palladium alloy of the form Pd.sub.x M.sub.y M'.sub.z where M is at least one element selected from the group consisting of silicon, iron, nickel, copper, chromium, cobalt, boron and aluminum and M' is at least one element selected from the group consisting of titanium, vanadium, chromium, zirconium, niobium, molybdenum, hafnium, tantalum and tungsten is provided. The alloys exhibit oxidation resistance and low electrical contact resistance and are particularly suited for electrical applications such as coatings for electrical contacts or connectors. In a preferred embodiment, the alloy is palladium/niobium containing from about 5 to about 10 atomic percent niobium.

Abstract: A palladium alloy of the form PdNbM where M is at least one element selected from the group consisting of silicon, iron, nickel, copper, cobalt, boron and aluminum is provided. The alloys exhibit oxidation resistance and electrical contact resistance and are particularly suited for electrical applications such as coatings for electrical contacts or connectors. In a preferred embodiment, the alloy contains from about 5 to about 10 atomic percent niobium.

Abstract: Machinable copper alloys having a reduced lead concentration are disclosed. An additive to the alloy accumulates both at the grain boundaries and intragranularly. The additive facilitates chip fracture or lubricates the tool. One additive is a mixture of bismuth and lead with the lead concentration below about 2% by weight.

Abstract: The present invention relates to copper-iron-nickel alloys having utility in electronic applications because of their low coefficients of expansion and high thermal conductivities. Alloys in accordance with the present invention consist essentially of from 10% to about 80% copper and the balance iron plus nickel with the ratio of iron to nickel being in the range of from about 1.5:1 to about 2.0:1. Preferred alloys have an iron to nickel ratio in the range of from about 1.6:1 to about 1.9:1. The process includes casting the alloy and treating the iron-nickel phase of alloy to minimize its surface volume. The treating step may comprise speroidizing the iron-nickel phase or applying an electromagnetic stirring force to the alloy during the casting step.

Abstract: Composite materials for electronic packages are disclosed. The composite materials comprise a core layer and first and second cladding layers. The core and cladding layer compositions and thicknesses are selected to maximize thermal and electrical conductivity and to minimize the coefficient of thermal expansion of the composite. The composite material may be employed to fashion the package base, the leadframe, a heat spreader or combinations thereof. In one embodiment, a portion of the first cladding layer is removed so that an electronic device may be mounted directly to a high thermal conductivity core.

Abstract: A kit for the assembly of an adhesively sealed package designed to encase an electronic device is provided. The kit comprises a metallic base and cover components which are adapted to receive a polymeric adhesive. At least those portions of the base and cover component which will contact the polymeric adhesive are provided with a coating of a second metal or oxide. In one embodiment, first, second and third dry film adhesives are tacked to the base and cover components.

Abstract: A metal package for housing an electronic device wherein the electronic device is attached to a severable die attach pad. The die attach pad is bonded to the base of the package with a thermally conductive medium. The base is bonded to the die attach pad and to the leadframe at the same time to reduce the thermal degradation of the sealants. In other embodiments, apertures are provided in the base component to enhance cooling of the electronic device and in the cover component to vent reaction by-products.

Abstract: A semiconductor package for an electrical component which has a metal or metal alloy leadframe with first and second surface, which leadframe is adapted to have an electrical component connected thereto. The leadframe is bonded by means of a polymer to a copper or copper alloy base member. The leadframe is also bonded by means of a polymer to a copper or copper alloy cap member. The cap and base members have coated to their inside surfaces a metal or metal alloy. The coating improves the polymer bond between the leadframe and the base and cap members. The surface area of the base member is increased to transfer more heat from the silicon chip in the semiconductor package and to reduce the thermal stresses between the silicon chip and the base member.

Abstract: The present invention relates to copper-iron-nickel composite materials having utility in electronic applications because of their low coefficients of expansion and high thermal conductivities. Composite materials in accordance with the present invention consist essentially of about 10% to 80% copper and the balance iron plus nickel with the ratio of iron to nickel being in the range of from about 1.5:1 to about 2.0:1. Preferred composite materials have an iron to nickel ratio in the range of from about 1.6:1 to about 1.9:1.

Abstract: The present invention relates to a process for forming improved bonds between components of electrical or electronic devices. The process of the present invention preferably comprises annealing a metallic substrate to form a substantially uniform, substantially continuous oxide layer on a surface of the substrate, exposing the oxidized substrate to a reducing atmosphere so as to form an irregular surface on the substrate, and bonding another component to the irregular surface.

Abstract: The present invention relates to a method for producing magnetic particles for use in recording media. The method comprises providing an alloy capable of forming a magnetic precipitate, aging the alloy to form a magnetic precipitate comprising a plurality of magnetic particles dispersed throughout a surrounding matrix; and dissolving the matrix to leave the magnetic particles. Magnetic particles produced by the present method are characterized by a size in the range of about 100 .ANG. to about 2000 .ANG., a single magnetic domain, an aspect ratio up to about 10:1, a relatively smooth surface, and a substantially uniform composition throughout.

Abstract: The present invention relates to techniques for producing magnetic particles for use in recording media. The process of the present invention generally comprises providing an alloy capable of forming a magnetic precipitate, aging the alloy to form a magnetic precipitate comprising a plurality of magnetic particles dispersed throughout a surrounding matrix; and dissolving the matrix to leave the magnetic particles. The dissolution of the matrix is done electrochemically using a pyrophosphate solution.

Abstract: The present invention relates to a method for producing magnetic particles for use in recording media. The method comprises providing an alloy capable of forming a magnetic precipitate, aging the alloy to form a magnetic precipitate comprising a plurality of magnetic particles dispersed throughout a surrounding matrix; and dissolving the matrix to leave the magnetic particles. Magnetic particles produced by the present method are characterized by a size in the range of about 100 .ANG. to about 2000 .ANG., a single magnetic domain, an aspect ratio up to about 10:1, a relatively smooth surface, and a substantially uniform composition throughout.

Abstract: An improved copper base alloy for use in electrical springs and a process of treating the alloy provide improved resistance to stress relaxation when the alloy is in a solution treated and aged condition having a discontinuous precipitate. The alloy consists essentially of from about 10% to about 15% nickel, from about 1% to about 3% aluminum, up to about 1% manganese, from about 0.05% to less than about 0.5% magnesium and the balance copper. The alloy is readily hot workable if held within a critical temperature range of from about 880.degree. C. to about 980.degree. C. prior to hot working.

Abstract: A high conductivity high temperature copper alloy containing mischmetal, phosphorus and magnesium with specific ratios among them. The alloy is free from internal copper oxides and may be annealed at elevated temperatures in hydrogen atmospheres without embrittlement. Strengths on the order of 80 KSI and conductivities on the order of 90% IACS are obtainable in cold worked material.