Highly Reliable Electrocaloric Behaviors of Antiferroelectric Al:ZrO₂Thin Films for Solid-State Cooling in Integrated Circuits

Heat generation in integrated circuits (ICs) has become a severe issue, which limits the utilization of miniaturized semiconductor devices in high-density 3-D IC technologies. Herein, Al2O3 was doped in ZrO2 thin films by plasma-enhanced atomic layer deposition (PEALD) to enhance their antiferroelectric (AFE) characteristics for highly reliable electrocaloric (EC) cooling applications. The cycling endurance in AFE behaviors of the Al:ZrO2 thin films under a high electric field of 5 MV/cm was significantly improved because of the enlargement of the energy bandgap with high resistance in trap-induced leakage current. Hence, the reliability of the EC effect of the 1% Al:ZrO2 thin film was examined with a negligible change in adiabatic temperature change ( $\Delta {T}$ ) of 2.6% after a cycling endurance test of $10^{{6}}$ cycles. With the competitive cycling reliabilities in AFE and EC behaviors, devices with optimized Al2O3-incorporated ZrO2 thin films show significant potential for future nanoscale cooling systems in chip-level ICs.