OBSERVATION OF MEYER-NELDEL RULE IN a- Se6oTe2oGe2o THIN FILMS IN PRESENCE OF LIGHT

摘要

In general, in case of semiconductors, conductivity (a) varies exponentially with temperature, in many amorphous and liquid semiconductors and many other class of materials. cr0 is found to increase exponentially with AE. This is called Meyer- Neldel rule. This rule is generally verified by selecting different compositions of different AE in a given class of materials. This opens a possibility of change in various other physical properties apart from AE. In the present paper, we report on the observation of Meyer- Neldel rule where AE is varied by varying the intensity of light while measuring the photoconductivity in amorphous thin films of Se6oTe2oGe2o instead of changing composition of the glassy system. The observation of Meyer-Neldel rule in the present case indicates that this rule is more general and does not cause due to change in density or distribution of defect states or any other physical property due to change in composition.