title: Tailoring the Electrical Properties of HfO2 MOS-Devices by Aluminum Doping.
abstract: In this work dielectric and electrical properties of Al-doped HfO2 layers deposited by plasma-enhanced atomic layer deposition in dependence on the thickness and the added Al amount in the films have been investigated. Special attention is dedicated to C-V and I-V hysteresis analysis as a measure for trapping phenomena in the films. A detailed study of conduction mechanisms in dependence on the composition of the layers has also been performed. The densities and spatial and energy positions of traps have been examined. It is found that only a small amount of Al-doping decreases the trapping which is assigned to a reduction of oxygen vacancy-related traps in HfO2. On the contrary, higher amounts of Al introduced in HfO2 films increase the trapping ability of the stacks which is due to the introduction of deeper Al2O3-related traps. The results imply that by adding a proper amount of Al into HfO2 it is possible to tailor dielectric and electrical properties of high-k layers toward meeting the criteria for particular applications.
authors.affiliation: †Institute of Solid State Physics, Bulgarian Academy of Sciences, 72 Tzarigradsko Chaussee, 1784 Sofia, Bulgaria.
authors.forename: Albena
authors.initials: A
authors.lastname: Paskaleva
authors.affiliation: ‡Fraunhofer Institute for Integrated Systems and Device Technology, Schottkystrasse 10, 91058 Erlangen, Germany.
authors.forename: Mathias
authors.initials: M
authors.lastname: Rommel
authors.affiliation: §Chair of Electron Devices, Friedrich-Alexander University Erlangen-Nuremberg, Cauerstrasse 6, 91058 Erlangen, Germany.
authors.forename: Andreas
authors.initials: A
authors.lastname: Hutzler
authors.affiliation: †Institute of Solid State Physics, Bulgarian Academy of Sciences, 72 Tzarigradsko Chaussee, 1784 Sofia, Bulgaria.
authors.forename: Dencho
authors.initials: D
authors.lastname: Spassov
authors.affiliation: ‡Fraunhofer Institute for Integrated Systems and Device Technology, Schottkystrasse 10, 91058 Erlangen, Germany.
authors.forename: Anton J
authors.initials: AJ
authors.lastname: Bauer
keywords: Al-doped HfO2; charge trapping memory; conduction mechanisms; high-k dielectrics; trapping