Showing papers on "Antimonide published in 1979"

Surface studies of multialkali antimonide (S20/S25) photocathodes

Abstract: Studies of a range of alkali antimonides and high-sensitivity S20 and S25 type multialkali photocathodes have led to an improved understanding of this type of photoemitter. In particular the role of Cs is clarified and the low work-function is believed to derive from a Cs-Sb dipole layer.

Gravitational influences on the liquid-state homogenization and solidification of aluminum antimonide. [space processing of solar cell material

Abstract: Although the III-V compound aluminum antimonide (AlSb) shows promise as a highly efficient solar cell material, its semiconducting properties have not been exploited for device development due to difficulties in synthesizing a homogeneous stoichiometric compound and growing single crystals by conventional techniques. Liquid-state homogenization analysis, which examines the relative influence of gravitational flowvs interatomic diffusion, suggested that the microscopic inhomogeneities observed in commercial polycrystalline samples could be due to gravitational influences caused by large density differences between Al- and Sb-rich phases in earth based melts. Several liquid-state homogenization and solidification experiments performed on earth and a similar experiment performed during the Apollo-Soyuz Test Project mission in July 1975 verify this theoretical conclusion. Using comparative characterization techniques for identically processed low and one gravity samples of commercially available AlSb, this paper reports on gravitational influences, such as density driven convection or sedimentation, that cause microscopic phase separation and nonequilibrium conditions to exist in earth based melts of AlSb. The reported experiments have, likewise, shown that such phase separations can be greatly reduced in a low gravity environment and lead to major improvements in microscopic homogeneity of the re crystallized material.

Neutron inelastic scattering experiments on uranium antimonide

Abstract: We report the first observation by neutron inelastic scattering of a collective elementary excitation in a metallic actinide compound. The excitation is longitudinally polarized with respect to the direction of the magnetic moment. The only other magnetic modes observed are at energies above 6 THz, and are essentially dispersionless.

Preparation and crystal structure of barium manganese antimonide (bamn2sb2), barium zinc antimonide (bazn2sb2) and barium cadmium antimonide (bacd2sb2)

Abstract: Die Darstellung der neuen Pnictide erfolgt aus stochiometrischen Gemengen der Elemente unter Ar durch Erhitzen auf 1600 K (I) bzw. 1300 K [(II) und (III)].

Surface-barrier structures on AlxGa1−xSb. I. Preparation and physical model of the contact

Abstract: The optimal conditions for preparing the surface and electrochemically depositing the metal have been determined for surface-barrier junctions of palladium on n-type gallium aluminum antimonide. The temperature and composition dependences of the voltage-current and voltage-capacitance characteristics of the junctions have been measured. When combined with the frequency dependence of the capacitance, these data show that, depending on the condition during formation, nearly ideal Schottky barriers are formed (i.e., a metal-intermediate layer-semiconductor system). The mechanism for current flow depends on the structure of the contact and the solid-solution composition. Anomalous barrier behavior at low temperatures is due to specific properties of the solid solution.