Abstract: The disclosed method can produce high T.sub.c superconductor material e.g., YBa.sub.2 Cu.sub.3 O.sub.7) of substantially increased intra-grain critical current density (J'.sub.c), as compared to conventionally produced bulk material of analogous composition. Exemplarily, YBa.sub.2 Cu.sub.3 O.sub.7 pellets produced according to the invention had J'.sub.c of about 10.sup.5 A/cm.sup.2 at 77 K. in an applied magnetic field of 0.9 Telsa. The inventive method comprises providing a precursor material whose composition differs from that of the desired superconductor with respect to at least one of the metal constituents of the desired superconductor. It further comprises heating the precursor material above the decomposition temperature (T.sub.d) of the precursor material such that a multiphase material results. The multiphase material comprises, in addition to a majority first phase, a dispersed precipitate phase. The method further comprises cooling the multiphase material to a temperature below T.sub.

Abstract: This invention is concerned with production of electrical devices comprising an electrodeposited conductive region free from cracking defects. In the production of a contact portion of the device from a metal strip electroplated with a conductive stripe of an alloy, the stripe exhibited, upon stamping and forming operation, cracked areas. Typically, the stripe coating on the metal strip, such as a copper bronze material, includes a layer of nickel, a layer of palladium alloyed with nickel, cobalt, arsenic or silver, and a flash coating of hard gold. The cracking defects were eliminated by subjecting the plated strip to an annealing treatment prior to the stamping and forming operation. After the heat-treatment, the stripe was free from cracks and separations between the successive layers.

Abstract: A semiconductor device with a low resistance ohmic contact, strongly adherent to the n-type surface of a body (11) of Group III-V compound semiconductor is obtained by a process including the sequential deposition of gold (13), tin (14) and gold (15) at a surface temperature of less than 200 degrees C followed by a heat treatment in a nonoxidizing atmosphere. This process has shown particular advantage when applied to aluminum containing compound semiconductors (e.g., gallium aluminum arsenide). For such use an initial deposition of aluminum (16) has proven particularly successful in producing consistently low resistance ohmic contacts. The invention has been used in the production of light emitting diodes.