Phase-change transition of chalcogenide system Ge8Sb2-xBixTe11 thin film using single femtosecond laser pulses

The phase transformation amorphous to crystalline of thin films Ge8Sb2-xBixTe11 system (where x = 0; 1; 2) deposited by the Flash Thermal Evaporation (FE). Phase transformation were induced by ultra-fast (40 fs) femtosecond single laser pulse irradiation, and were compared in structure, optical properties and topography. The obtained results demonstrate, that single fs pulse laser irradiation appears to be effective in inducing crystallization of Ge8Sb2-xBixTe11 thin films and enabling the attainment of a higher speed data set/reset. The substitution of bismuth for antimony leads to a change in optical, electrical and thermal properties depending on the Bi concentration for the studied materials. The high optical contrast makes the studied Ge8Sb2-xBixTe11 samples promising for PRAM memories.