Current conduction of 0.72 nm equivalent-oxide-thickness LaO/HfO ₂ stacked gate dielectrics

Metal-oxide-semiconductor capacitors (MOSCs) incorporating atomic layer deposited (ALD) LaO/HfO₂ stacked gate dielectrics were fabricated, where the equivalent oxide thickness (EOT) of the high- k dielectrics is only 0.72 nm and the gate leakage (J_g) is as low as 6.8× 10-2 A/ cm². Based on the analysis of the temperature dependence of the gate leakage current from 300 to 500 K, the main current conduction is found to be Schottky emission or Poole-Frankel emission. Moreover, the barrier height (Φ_B) at TaC and HfLaO interface is estimated to be about 1.21 eV, and the trap energy level (Φ_t) is about 0.51 eV.