John S. Berkes

Phase separation in amorphous chalcogenides

Abstract Systematic variations of electrical and optical properties of amorphous chalcogenides can be obtained by forming multicomponent solutions with elements of other periodic groups. A limitation on the preparation and stability of such solutions is the occurrence of liquid-liquid phase separation in the stable and metastable melts. This paper examines the effect of such phase separation on glass formation and stability in chalcogenide systems, giving particular emphasis to the BiSe and SbSe systems which display stable and incipient immiscibility, respectively.

Phase Relations and Liquid Structure in the System As ‐ Sb2Se3 ‐ Se

The phase equilibria for the ternary system were determined by sealed system DTA and quench methods. The and ternary sections are true binary systems exhibiting simple eutectic behavior. The general phase relationships are discussed and the liquidus behavior and liquid structure of the selenium rich part of the ternary are treated in detail. A nonregular thermodynamic solution model is used to describe the solution behavior and calculate the size of structural units present in the ternary liquid. A physical interpretation, in terms of these structural units, is given for the observed incipient liquid immiscibility.