X-ray microanalysis of quaternary semiconductor solid solutions and its application to the (SnTe-SnSe): In system

A reliable technique of local chemical characterization of multicomponent s emiconductor solid solutions has been developed, and the possibility of its application to the SnTe-SnSe quaternary solid solutions doped with 16 at. % In verified. The behavior of the electrical resistivity of samples of the se solid solutions at low temperatures, 0.4-4.2 K, has been studied. The cr itical temperature T-c and the second critical magnetic field H-c2 of the s uperconducting transition and their dependences on the solid-solution compo sition have been determined. The superconducting transition at T-c approxim ate to 2 - 3 K is due to hole filling of the In-impurity resonance states, and the observed variation of the superconducting transition parameters wit h increasing Se content in the solid solution is related to the extrema in the valence band and the In band of resonance states shifting with respect to one another. (C) 1999 American Institute of Physics. [S1063-7834(99)0100 4-7].