%0 Journal Article %A Kang, Yu-Seon %A Kang, Hang-Kyu %A Kim, Dae-Kyoung %A Jeong, Kwang-Sik %A Baik, Min %A An, Youngseo %A Kim, Hyoungsub %A Song, Jin-Dong %A Cho, Mann-Ho %D 2016 %T Structural and Electrical Properties of EOT HfO2 (<1 nm) Grown on InAs by Atomic Layer Deposition and Its Thermal Stability %U https://acs.figshare.com/articles/journal_contribution/Structural_and_Electrical_Properties_of_EOT_HfO_sub_2_sub_1_nm_Grown_on_InAs_by_Atomic_Layer_Deposition_and_Its_Thermal_Stability/3101404 %R 10.1021/acsami.5b10975.s001 %2 https://acs.figshare.com/ndownloader/files/4818664 %K Atomic Layer Deposition %K EOT %K InAs substrate %K HfO 2 dielectric %K nm equivalent oxide thickness %K HfO 2 structure %K HfO 2 film %K post deposition annealing %K HfO 2 %K PDA %K defect states %X We report on changes in the structural, interfacial, and electrical characteristics of sub-1 nm equivalent oxide thickness (EOT) HfO2 grown on InAs by atomic layer deposition. When the HfO2 film was deposited on an InAs substrate at a temperature of 300 °C, the HfO2 was in an amorphous phase with an sharp interface, an EOT of 0.9 nm, and low preexisting interfacial defect states. During post deposition annealing (PDA) at 600 °C, the HfO2 was transformed from an amorphous to a single crystalline orthorhombic phase, which minimizes the interfacial lattice mismatch below 0.8%. Accordingly, the HfO2 dielectric after the PDA had a dielectric constant of ∼24 because of the permittivity of the well-ordered orthorhombic HfO2 structure. Moreover, border traps were reduced by half than the as-grown sample due to a reduction in bulk defects in HfO2 dielectric during the PDA. However, in terms of other electrical properties, the characteristics of the PDA-treated sample were degraded compared to the as-grown sample, with EOT values of 1.0 nm and larger interfacial defect states (Dit) above 1 × 1014 cm–2 eV–1. X-ray photoelectron spectroscopy data indicated that the diffusion of In atoms from the InAs substrate into the HfO2 dielectric during the PDA at 600 °C resulted in the development of substantial midgap states. %I ACS Publications