Improved interfacial and electrical properties of HfLaON gate dielectric Ge MOS capacitor by NbON/Si dual passivation layer and fluorine incorporation

� 2016 Author(s). Ge metal-oxide-semiconductor (MOS) capacitor with HfLaON/(NbON/Si) stacked gate dielectric and fluorine-plasma treatment is fabricated, and its interfacial and electrical properties are compared with its counterparts without the Si passivation layer or the fluorine-plasma treatment. The experimental results show that the HfLaON/(NbON/Si) Ge MOS device treated by fluorine plasma exhibits excellent performance: low interface-state density (4.3 � 1011cm-2eV-1), small flatband voltage (0.22 V), good capacitance-voltage behavior, small frequency dispersion and low gate leakage current (4.18 � 10-5A/cm2at Vg= Vfb+ 1 V). These should be attributed to the suppressed growth of unstable Ge oxides on the Ge surface during gate-dielectric annealing by the NbON/Si dual interlayer and fluorine incorporation, thus reducing the defective states at/near the NbSiON/Ge interface and improving the electrical properties of the device.