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Title: Cubic HfO{sub 2} doped with Y{sub 2}O{sub 3} epitaxial films on GaAs (001) of enhanced dielectric constant

Abstract

Nanometer thick cubic HfO{sub 2} doped with 19 at. % Y{sub 2}O{sub 3} (YDH) epitaxial films were grown on GaAs (001) using molecular beam epitaxy. Structural studies determined the epitaxial orientation relationships between the cubic YDH films and GaAs to be (001){sub GaAs}//(001){sub YDH} and [100]{sub GaAs}//[100]{sub YDH}. The YDH structure is strain relaxed with a lattice constant of 0.5122 nm with a small mosaic spread of 0.023 deg. and a twist angle of 2.9 deg. The YDH/GaAs interface is atomically abrupt without evidence of reacted interfacial layers. From C-V and I-V measurements a 7.7 nm thick YDH film has an enhanced dielectric constant {kappa}{approx}32, an equivalent oxide thickness of {approx}0.94 nm, an interfacial state density D{sub it}{approx}7x10{sup 12} cm{sup -2} eV{sup -1}, and a low leakage current density of 6x10{sup -5} A/cm{sup 2} at 1 V gate bias.

Authors:
; ; ; ; ; ; ;  [1];  [2];  [2]
  1. Department of Materials Science and Engineering, National Tsing Hua University, Hsinchu 30013, Taiwan (China)
  2. (China)
Publication Date:
OSTI Identifier:
20960211
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 90; Journal Issue: 15; Other Information: DOI: 10.1063/1.2722226; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; CRYSTAL GROWTH; CUBIC LATTICES; DIELECTRIC MATERIALS; DOPED MATERIALS; GALLIUM ARSENIDES; GRAIN ORIENTATION; HAFNIUM OXIDES; INTERFACES; LATTICE PARAMETERS; LAYERS; LEAKAGE CURRENT; MOLECULAR BEAM EPITAXY; PERMITTIVITY; THIN FILMS; TRANSMISSION ELECTRON MICROSCOPY; X-RAY DIFFRACTION; YTTRIUM OXIDES

Citation Formats

Yang, Z. K., Lee, W. C., Lee, Y. J., Chang, P., Huang, M. L., Hong, M., Hsu, C.-H., Kwo, J., Research Division, National Synchrotron Radiation Research Center, Hsinchu 30076, Taiwan, and Department of Physics, National Tsing Hua University, Hsinchu, 30013, Taiwan. Cubic HfO{sub 2} doped with Y{sub 2}O{sub 3} epitaxial films on GaAs (001) of enhanced dielectric constant. United States: N. p., 2007. Web. doi:10.1063/1.2722226.
Yang, Z. K., Lee, W. C., Lee, Y. J., Chang, P., Huang, M. L., Hong, M., Hsu, C.-H., Kwo, J., Research Division, National Synchrotron Radiation Research Center, Hsinchu 30076, Taiwan, & Department of Physics, National Tsing Hua University, Hsinchu, 30013, Taiwan. Cubic HfO{sub 2} doped with Y{sub 2}O{sub 3} epitaxial films on GaAs (001) of enhanced dielectric constant. United States. doi:10.1063/1.2722226.
Yang, Z. K., Lee, W. C., Lee, Y. J., Chang, P., Huang, M. L., Hong, M., Hsu, C.-H., Kwo, J., Research Division, National Synchrotron Radiation Research Center, Hsinchu 30076, Taiwan, and Department of Physics, National Tsing Hua University, Hsinchu, 30013, Taiwan. Mon . "Cubic HfO{sub 2} doped with Y{sub 2}O{sub 3} epitaxial films on GaAs (001) of enhanced dielectric constant". United States. doi:10.1063/1.2722226.
@article{osti_20960211,
title = {Cubic HfO{sub 2} doped with Y{sub 2}O{sub 3} epitaxial films on GaAs (001) of enhanced dielectric constant},
author = {Yang, Z. K. and Lee, W. C. and Lee, Y. J. and Chang, P. and Huang, M. L. and Hong, M. and Hsu, C.-H. and Kwo, J. and Research Division, National Synchrotron Radiation Research Center, Hsinchu 30076, Taiwan and Department of Physics, National Tsing Hua University, Hsinchu, 30013, Taiwan},
abstractNote = {Nanometer thick cubic HfO{sub 2} doped with 19 at. % Y{sub 2}O{sub 3} (YDH) epitaxial films were grown on GaAs (001) using molecular beam epitaxy. Structural studies determined the epitaxial orientation relationships between the cubic YDH films and GaAs to be (001){sub GaAs}//(001){sub YDH} and [100]{sub GaAs}//[100]{sub YDH}. The YDH structure is strain relaxed with a lattice constant of 0.5122 nm with a small mosaic spread of 0.023 deg. and a twist angle of 2.9 deg. The YDH/GaAs interface is atomically abrupt without evidence of reacted interfacial layers. From C-V and I-V measurements a 7.7 nm thick YDH film has an enhanced dielectric constant {kappa}{approx}32, an equivalent oxide thickness of {approx}0.94 nm, an interfacial state density D{sub it}{approx}7x10{sup 12} cm{sup -2} eV{sup -1}, and a low leakage current density of 6x10{sup -5} A/cm{sup 2} at 1 V gate bias.},
doi = {10.1063/1.2722226},
journal = {Applied Physics Letters},
number = 15,
volume = 90,
place = {United States},
year = {Mon Apr 09 00:00:00 EDT 2007},
month = {Mon Apr 09 00:00:00 EDT 2007}
}
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