Title: Silicon orientation effects in the atomic layer deposition of Hafnium oxide
Authors: Nyns, Laura ×
Ragnarsson, LA
Hall, L
Delabie, Annelies
Heyns, Marc
Van Elshocht, S
Vinckier, Christiaan
Zimmerman, P
De Gendt, Stefan #
Issue Date: 2008
Publisher: Electrochemical Society
Series Title: Journal of the Electrochemical Society vol:155 issue:2 pages:G9-G12
Abstract: The continuous downscaling of complementary metal oxide semiconductor devices demands the introduction of dielectric layers with a high permittivity kappa. Three-dimensional (3D) transistor structures, such as FinFET devices, require excellent step coverage by the high-kappa material as provided by atomic layer deposition (ALD). In addition, because of the 3D structure, surfaces with different crystallographic orientation need to be covered. Because the initial HfO2 deposition using ALD HfCl4/H2O is governed by the OH surface density, we investigated its dependence on the crystallographic orientation of the silicon substrate. For oxidations in O-3/H2O, a (110) orientated substrate oxidizes faster than silicon (100) up to a thickness of similar to 0.7 nm as measured by X-ray photoelectron spectroscopy. Also, irrespective of the substrate orientation, the HfO2 deposition is found to increase with increasing SiO2 thickness and thus OH coverage of the surface. This implies that, for oxide thicknesses below0.7 nm, the oxidation of silicon (100) results in a thinner oxide and, hence, less HfO2 deposition in comparison to silicon (110). However, these differences are marginal after implementation in transistor devices as is shown by their capacitance and mobility. As a result, for FinFET applications, a conformally deposited HfO2 layer will be independent of the crystallographic substrate orientation.
ISSN: 0013-4651
Publication status: published
KU Leuven publication type: IT
Appears in Collections:Molecular Design and Synthesis
Department of Materials Engineering - miscellaneous
× corresponding author
# (joint) last author

Files in This Item:

There are no files associated with this item.

Request a copy


All items in Lirias are protected by copyright, with all rights reserved.

© Web of science