Impact of oxidation and reduction annealing on the electrical properties of Ge/La2O3/ZrO2 gate stacks

► Ge surface passivation by scalable multilayer of La2O3/ZrO2. ► LaxGeyOz interfacial layers thickness controllable by oxidation time. ► Forming gas annealing improves Dit down to 3 × 1011 eV−1 cm−2 in presence of LaxGeyOz interlayer. ► Trade-off between interface trap density and equivalent oxide thickness.