The initial structures of two types – HfO2(50 nm)/Si (100) and W(150 nm)/HfO2(5 nm)/Si (100) – were prepared by radio frequency magnetron sputtering (RF-MS) in Ar+-plasma and further were subjected to the annealing at 500-950 °C followed by forming an ohmic contact to Si-substrate. Investigation of the first type structures show that differences in various crystalline modifications and kind of I-V curves strongly depend on conditions of growth of the HfO2 films during RF-MS process where RF bias Ubias, applying to the substrate, is an effective parameter for quality and growth process control of the HfO2 films. For the second type structures, the ultrathin HfO2 films were grown at Ubias= -7 V, then an effect of RTA at 950 °C in a neutral atmosphere on both electrical characteristics and chemical state at interfaces was studied. In comparison with as-deposited structures, RTA leads to decrease in the both the maximum specific capacitance in accumulation of C-V characteristics (by 30 %) and the dielectric constant (from 27 to 23). The thermally activated processes of formation of WOx phase at the W/HfO2 interface and Hf-silicate phase (HfSixOy) at the HfO2/Si (100) interface were observed. The total thickness of formed oxide layer exceeded the thickness of as-deposited HfO2 film by 30 %.
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