Type

Journal Article

Authors

T. C. Q. Noakes
P. Bailey
R. C. Barklie
S. Wright
Greg Hughes
Stephen McDonnell
D. O’Connell
P. K. Hurley
M. Modreanu
M. A. Negara
and 3 others

Subjects

Physics

Topics
mis structures thickness dielectric thin films permittivity transistors electron beam deposition deposition x ray photoelectron spectra hafnium compounds high resolution transmission electron microscopy interface gate dielectrics defects silicon layer thin films x ray photoelectron spectroscopy high k dielectric thin films transmission electron microscopy hafnium oxide physics

Electrical, structural, and chemical properties of HfO₂ films formed by electron beam evaporation (2008)

Abstract High dielectric constant hafnium oxide films were formed by electron beam (e-beam) evaporation on HF last terminated silicon (100) wafers. We report on the influence of low energy argon plasma ( ∼ 70 eV) and oxygen flow rate on the electrical, chemical, and structural properties of metal-insulator-silicon structures incorporating these e-beam deposited HfO2 films. The use of the film-densifying low energy argon plasma during the deposition results in an increase in the equivalent oxide thickness (EOT) values. We employ high resolution transmission electron microscopy (HRTEM), x-ray photoelectron spectroscopy (XPS), and medium energy ion scattering experiments to investigate and understand the mechanisms leading to the EOT increase. We demonstrate very good agreement between the interfacial silicon oxide thicknesses derived independently from XPS and HRTEM measurements. We find that the e-beam evaporation technique enabled us to control the SiOx interfacial layer thickness down to ∼ 6 Å. Very low leakage current density (<10−4 A/cm2) is measured at flatband voltage +1 V into accumulation for an estimated EOT of 10.9±0.1 Å. Based on a combined HRTEM and capacitance-voltage (CV) analysis, employing a quantum-mechanical CV fitting procedure, we determine the dielectric constant (k) of HfO2 films, and associated interfacial SiOx layers, formed under various processing conditions. The k values are found to be 21.2 for HfO2 and 6.3 for the thinnest ( ∼ 6 Å) SiOx interfacial layer. The cross-wafer variations in the physical and electrical properties of the HfO2 films are presented.
Collections Ireland -> Dublin City University -> Publication Type = Article
Ireland -> Dublin City University -> Status = Published
Ireland -> University College Cork -> Tyndall National Institute
Ireland -> Dublin City University -> DCU Faculties and Centres = DCU Faculties and Schools: Faculty of Science and Health
Ireland -> Dublin City University -> Subject = Physical Sciences: Physics
Ireland -> Dublin City University -> Subject = Physical Sciences
Ireland -> Dublin City University -> DCU Faculties and Centres = DCU Faculties and Schools: Faculty of Science and Health: School of Physical Sciences
Ireland -> University College Cork -> Research Institutes and Centres
Ireland -> Dublin City University -> DCU Faculties and Centres = DCU Faculties and Schools
Ireland -> University College Cork -> Tyndall National Institute - Journal Articles
Ireland -> Dublin City University -> Subject = Physical Sciences: Thin films

Full list of authors on original publication

T. C. Q. Noakes, P. Bailey, R. C. Barklie, S. Wright, Greg Hughes, Stephen McDonnell, D. O’Connell, P. K. Hurley, M. Modreanu, M. A. Negara and 3 others

Experts in our system

1
Greg Hughes
Dublin City University
Total Publications: 29
 
2
Stephen McDonnell
University College Cork
Total Publications: 8
 
3
Paul K. Hurley
University College Cork
Total Publications: 78
 
4
Mircea Modreanu
University College Cork
Total Publications: 16