Dependence of the Hall mobility on composition in As₂(S, Se, Te)₃ glasses

Abstract

Hall effect measurements have been made on vitreous As₂Se_2.5S_0.5, As₂SSeTe, and As₂Se_xTe_3-x with x = 2.94 and 2.62. Using results from some previous papers (Roilos 1971, Roilos and Mytilineou 1974), it is possible to make a rather detailed survey of the compositional dependence of the Hall mobility in the amorphous system As₂(S, Se, Te)₃. The Hall mobility decreases by a factor of about two as the As₂Te₃ content in the As₂Se_xTe_3-x glasses is increased from zero up to 40%; it then increases to its initial value at about 75 % As₂Te₃ and remains roughly constant up to the compound As₂Te₃. The Hall mobility activation energy shows a similar behaviour, in contrast to the conductivity activation energy which decreases monotonically with increasing As₂Te₃ content.

The results are discussed in terms of various models for the Hall effect in amorphous semiconductors.