ePubs
The open archive for STFC research publications
Home
About ePubs
Content Policies
News
Help
Privacy/Cookies
Suggest an Enhancement
Contact ePubs
Full Record Details
Persistent URL
http://purl.org/net/epubs/work/49250
Record Status
Checked
Record Id
49250
Title
Electrical, structural, and chemical properties of HfO2 films formed by electron beam evaporation
Contributors
K Cherkaoui (Tyndall National Institute)
,
S Monaghan (Tyndall National Institute)
,
MA Negara (Tyndall National Institute)
,
M Modreanu (Tyndall National Institute)
,
PK Hurley (Tyndall National Institute)
,
D O'Connell (Dublin City U.)
,
S McDonnell (Dublin City U.)
,
G Hughes (Dublin City U.)
,
S Wright (Trinity College Dublin)
,
RC Barklie (Trinity College Dublin)
,
P Bailey (STFC Daresbury Lab.)
,
TCQ Noakes (STFC Daresbury Lab.)
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.
Organisation
SRS
,
MEIS
,
STFC
Keywords
Materials
Funding Information
Related Research Object(s):
Licence Information:
Language
English (EN)
Type
Details
URI(s)
Local file(s)
Year
Journal Article
J Appl Phys
104 (2008): 064113.
doi:10.1063/1.2978209
2008
Showing record 1 of 1
Recent Additions
Browse Organisations
Browse Journals/Series
Login to add & manage publications and access information for OA publishing
Username:
Password:
Useful Links
Chadwick & RAL Libraries
SHERPA FACT
SHERPA RoMEO
SHERPA JULIET
Journal Checker Tool
Google Scholar