[摘要]：The electrical properties of plasma-enhanced atomic-layer-deposited (PE-ALD) TiO2 as gate dielectric were investigated for germanium-channel complementary metal-oxide-semiconductor capacitors by using ultrathin in situ HfO2/GeO2 interlayers. TiO2 grown by PE-ALD exhibited a k value of 50 +/- 5. An equivalent oxide thickness of 0.9 nm was obtained for the TiO2(3 nm)/HfO2(1.2 nm)/GeO2(0.7 nm)/Ge capacitor with very low leakage current density of 2x10(-7) A/cm(2) at V-FB +/- 1 V. Capacitance-voltage hysteresis was below 30 mV for the TiO2/HfO2/GeO2/Ge capacitors. Relatively low minimum density of interface states, D-it similar to 5x10(11) eV(-1) cm(-2) was obtained, suggesting the potential of HfO2/GeO2 passivation layer for the application of TiO2 as gate dielectric for both p- and n-type Ge channels. (C) 2010 American Institute of Physics. [doi: 10.1063/1.3490710]
