Ion-irradiation-induced selective bond rearrangements in amorphous GeTe thin films

The change in the local order of amorphous sputter deposited GeTe thin films irradiated with ${\text{Ge}}^{+}$ ion and its influence on the subsequent thermal induced crystallization has been investigated by means of micro-Raman spectroscopy and in situ time-resolved reflectivity. A reduction in the Ge-rich tetrahedral species and an enhancement of the crystallization kinetics occurred in the irradiated amorphous samples. The rearrangement of the amorphous network is suggested to be related to thermal spikes effects rather than to the defects produced by the ions in the collision cascade.