%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