Transient conductivity studies in tellurium thin films

Abstract

Laser-induced phase transformations in Te thin films have been studied utilizing time-resolved conductivity measurements. The dynamics of melting, recrystallization, and the onset of amorphization as a function of laser fluence have been investigated. Results are presented for melt duration, depth, and velocities (melt in and regrowth) with ns-time resolution. The necessary conditions for glass formation directly from the melt in Te are also determined. This necessitates complete melt through to the substrate interface and requires no first-order transition. Heat-flow calculations indicate large undercooling in the dynamics of recrystallization and that the material response to the excimer laser radiation is purely thermal.