Abstract: A bonding or superfine wire is provided made of copper, with a gold enrichment on the surface thereof, in particular in an amount corresponding to a coating of at most 50 nm. The wire may be bonded by the ball/wedge method, has a copper-colored appearance, and the ball thereof after flame-off has a hardness of less than 95 according to HV0.002. In order to produce the bonding or superfine wire, a copper wire is coated with gold or a copper-gold alloy or gold is introduced into the surface of the copper wire. The wires are bonded to a semiconductor silicon chip.

Abstract: The invention relates to a gold alloy containing 99 wt. %, preferably 99.9 wt. % gold, and 1 to 1000 ppm, preferably 10 to 100 ppm calcium, and 1 to 1000 ppm, preferably 10 to 100 ppm ytterbium or europium or a mixture of ytterbium and europium, as well as a method for producing a homogeneous gold alloy containing europium and/or ytterbium.

Abstract: A bonding or superfine wire is provided made of copper, with a gold enrichment on the surface thereof, in particular in an amount corresponding to a coating of at most 50 nm. The wire may be bonded by the ball/wedge method, has a copper-colored appearance, and the ball thereof after flame-off has a hardness of less than 95 according to HVO.002. In order to produce the bonding or superfine wire, a copper wire is coated with gold or a copper-gold alloy or gold is introduced into the surface of the copper wire. The wires are bonded to a semiconductor silicon chip.

Abstract: To prevent defoliation or splitting-off of an aluminum or aluminum alloy which is roll-plated on a copper or copper alloy base, an intermediate nickel layer having less than 0.05% contaminants is applied beneath the aluminum layer. If the base is a copper alloy, an intermediate copper layer which is of an oxygen-free copper or copper alloy is placed between the base and the nickel layer. Typical dimensions are: base copper layer (1, 13): 0.25 mm; oxygen-free copper layer (7, 15): 0.005 to 0.01 mm; nickel layer with less than 0.05% contaminants or impurities: about 0.01 mm; AlSi 0.5 aluminum alloy: 0.005 to 0.006 mm.

Abstract: A cable for connecting a cardiac pacemaker to an electrode inserted in the heart through the blood stream utilizes a die-clad conductor or a number ofthem, especially several die-clad strands forming a twisted conductor of the stranded type, enclosed in a covering tube of a synthetic elastomer. The core of each die-clad strand is of a highly conducting metal, such as copper or a high-copper alloy. The outer cladding is a metal selected from the group consisting of tantalum, titanium, zirconium, niobium, titanium-base alloys, platinum, platinum-iridium alloys, platinum-palladium alloys and platinum-rhodium alloys. The cladding thickness is in the range from 0.0025 to 0.035 mm, while the cord diameter is between 0.04 to 0.3 mm. When tantalum, titanium, zirconium, niobium or titanium-alloy cladding is used, the outer surface can be made electrically insulating, preferably by anodizing.

Abstract: To reduce failure and breakage of connecting wires connecting specific zones on semiconductor chips to semiconductor frames, the connecting wires are made of an aluminum-copper alloy having, by weight, 3 to 5%, preferably 4% copper, the remainder aluminum (neglecting incidental impurities), the diameter of the wires being between about 0.01 to 0.06 mm, preferably about 0.02 to 0.05 mm, connected to the frame and the semiconductor, respectively, by ultrasonic bonding.

Abstract: To prevent metal fatique, particularly when making a button loop, or nail head thermo compression bond connection to a semiconductor, the connecting wire has a core of copper, or a copper alloy of at least 60% copper content, and a jacket of aluminum, or aluminum alloy, of at least 95% aluminum content; in a preferred form, the core is 94% copper and 6% tin, and the jacket is, for example, 99% aluminum, 1% silicon; 96% aluminum, 4% copper; or 99% aluminum, 1% magnesium, all percentages by weight.

Abstract: A low-power electrical contact particularly suitable for switching and plug-in connections. The contact comprises an outer contact layer and a substrate composed of a copper base alloy. The contact layer consists essentially of an alloy of 35-55% by weight gold, 18-33.5% silver, 30-40% palladium, and (i) 1-6% indium, or (ii) 0.5-2% tin together with 0.5-2% indium. An intermediate layer of nickel or copper-nickel may be interposed between the contact layer and the substrate.