Optimization of 3ω Method for Phase-Change Materials Thermal Conductivity Measurement at High Temperature

Thermal conductivity (kth) of Ge-rich Ge-Sb-Te phase-change material (GGST) is here investigated at temperatures up to $400\ ^{\circ}\mathrm{C}$ through “3ω method”. We present the engineering of the test vehicle, with the optimization of the metal-based heater to achieve a reliable measurement even at high temperature. Finally, we compare the results from four different approaches, showing which method is more accurate for the kth evaluation in phase-change materials.