Crystallization kinetics of amorphous Ga–Sb–Te chalcogenide films: Part I. Nonisothermal studies by differential scanning calorimetry

Nonisothermal crystallization kinetics of amorphous chalcogenide Ga–Sb–Te films with compositions along the pseudo-binary tie-lines connecting Sb₇Te₃−GaSb and Sb₂Te₃–GaSb of the ternary phase diagram were investigated by means of differential scanning calorimetry. Powder samples were prepared firstly by film deposition using a co-sputtering method; the films were then stripped from the substrate. The activation energy (E_a) and rate factor (K_o) were evaluated from the heating rate dependency of the crystallization temperature using the Kissinger method. The kinetic exponent (n) was deduced from the exothermic peak integrals using the Ozawa method. The crystallization temperature (T_x = 181 to 327 °C) and activation energy (E_a= 2.8 to 6.5 eV) increased monotonically with increasing GaSb content and reached a maximum value in compositions located at the vicinity of GaSb. The kinetic exponent is temperature dependent and shows higher values in the SbTe-rich compositions. Promising media compositions worthy of further studies were identified through the determined kinetics parameters.