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Hafnium-oxide (HfO$_2$) thin films were deposited on p-type (100) silicon wafers by using atomic layer deposition (ALD) with tetrakis (ethylmthylamino)-hafnium [TEMAH] and ozone. Prior to the deposition of the HfO$_2$ thin films, a thin Hf (10 \AA) metal layer was deposited. The deposition temperature of the HfO$_2$/Hf thin film was 350 $^\circ$C and, its total thickness was 150 \AA. The deposited samples were annealed in a furnace under nitrogen ambient. Round-type MOS capacitors were fabricated with Pt electrodes prepared by using an e-beam evaporator. We observed the formation of Hf-O-Si bonds, instead of Si-O bonds, at the interface. The HfSiO layer was grown between the HfO$_2$ and Si; therefore, the Hf metal layer sandwiched in the HfO$_2$/Si structure was effectively suppressed to grow interfacial SiO$_x$. The MOS capacitance of the HfO$_2$/Hf/Si structure was larger than that of the HfO$_2$/Si structure. The dielectric constant of the HfO$_2$/Hf layer was $\sim$18.96, and the interface state density at the silicon interface was 2.2 $\times$ 10$^{-12}$ cm$^{-2}$eV$^{-1}$.


Hafnium-oxide (HfO$_2$) thin films were deposited on p-type (100) silicon wafers by using atomic layer deposition (ALD) with tetrakis (ethylmthylamino)-hafnium [TEMAH] and ozone. Prior to the deposition of the HfO$_2$ thin films, a thin Hf (10 \AA) metal layer was deposited. The deposition temperature of the HfO$_2$/Hf thin film was 350 $^\circ$C and, its total thickness was 150 \AA. The deposited samples were annealed in a furnace under nitrogen ambient. Round-type MOS capacitors were fabricated with Pt electrodes prepared by using an e-beam evaporator. We observed the formation of Hf-O-Si bonds, instead of Si-O bonds, at the interface. The HfSiO layer was grown between the HfO$_2$ and Si; therefore, the Hf metal layer sandwiched in the HfO$_2$/Si structure was effectively suppressed to grow interfacial SiO$_x$. The MOS capacitance of the HfO$_2$/Hf/Si structure was larger than that of the HfO$_2$/Si structure. The dielectric constant of the HfO$_2$/Hf layer was $\sim$18.96, and the interface state density at the silicon interface was 2.2 $\times$ 10$^{-12}$ cm$^{-2}$eV$^{-1}$.