Effect of substrate temperature and biasing on the formation of 110 K BiSrCaCuO superconducting single target sputtered thin films AIP Conf.Kinetics of the 110 K superconducting phase formation has been studied in the Bi-Sr-Ca-Cu-O system with and without the addition of small amounts of lead. The kinetics of the phase transformation has been greatly affected by lead doping. The time required for the maximum formation of the 110 K phase is substantially reduced by the addition of lead. This phenomenon has been shown to be associated with the lead enhancing the nucleation and growth process of the 110 K phase and the diffusivity of calcium and copper.

dc photoconductivity characteristics of HgI z single crystals have been measured in the range of 1.75-2.75 eV, using CuI as a transparent electrical contact. Hole and electron photocurrents could be separately measured by applying different voltage polarities to the illuminated electrode. It is shown that charge carrier generation near the surface is highly extrinsic, as displayed by differences in the hole and electron photogeneration spectra. Analysis of the photoconductivity versus voltage characteristics indicates that the hole and electron bulk trapping times satisfy 'Tp > 70 ps and 'Tn > 3 ps, respectively. The hole and electron surface recombination velocities were sp = 1.0 X lif cm/s and Sn = 8 X Hf cm/s, respectively.

A uniform grain-oriented microstructure was developed in 50-mm-long bar samples of bulk YBa2Cu3Ox prepared by a partial melt growth process. In sharp contrast to previous reports, the textured products contained only small amounts of second phases. The samples were dense and nearly free of porosity. Transport measurements showed that the textured samples could carry a critical current density greater than 4.4×104 A/cm2 at 77 K and 1.8 T. The possible effects of processing parameters on the superconducting properties of the tested materials are discussed.

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