La-incorporated HfO2 could improve the thermal stability and interface trap quality. Laminated structures with different doping positions and thicknesses were fabricated by RF magnetron co-sputtering method. The physical and electrical properties of HfO2/HfLaO/p-Si and HfLaO/HfO 2/p-Si structures after 850 °C postannealing were analyzed. And the time dependent dielectric breakdown (TDDB) characteristics were also analyzed for metal-oxide-semiconductor (MOS) capacitors with atomic-layer-deposited (ALD) HfLaO gate dielectrics. For TDDB characteristics, the Weibull slopes were independent of stress voltages and capacitor areas, but they were dependent on the stress temperatures. The electric-field acceleration parameter (γ) is about 4.3-4.5 MV/cm. The maximum voltage (Vg) for 10-year TDDB lifetime under 85 °C operation is Vg = 2.03 V, or equivalently 6.1 MV/cm.
ASJC Scopus subject areas