Hier finden Sie wissenschaftliche Publikationen aus den Fraunhofer-Instituten.

Effective work function engineering by lanthanide ion implantation of metal-oxide semiconductor gate stacks

: Fet, A.; Häublein, V.; Bauer, A.J.; Ryssel, H.


Müssig, H.-J.:
15th Workshop on Dielectrics in Microelectronics, WoDiM 2008. Papers : 23 - 25 June 2008, Bad Saarow (Berlin)
New York, N.Y.: AIP Press, 2009 (Journal of vacuum science and technology. B, microelectronics and nanometers 27.2009, Nr.1)
ISBN: 978-0-9823012-1-0
ISSN: 1071-1023
Workshop on Dielectrics in Microelectronics (WoDiM) <15, 2008, Berlin>
Conference Paper, Journal Article
Fraunhofer IISB ()

While the debate about the exact cause of Fermi level pinning in metal-high-k dielectric gate stacks is ongoing, several solutions for engineering the threshold voltage V-t of the gate stacks have been proposed. Engineering the flat-band. voltage V-fb, translates into an effective control of the threshold voltage. This study uses ion implantation as a tool to adjust V-fb by doping the gate stack. It is shown that lanthanide implantation can modulate the effective work function for n-type gate electrodes. Ion implantation of dysprosium (Dy) and lanthanum (La) into the gate stack achieves significant flat-band voltage. shifts of about -1 and -3 V, respectively, for a dose of 1 X 10(14) cm(-1). By increasing the implantation dose and energy, larger shifts in the flat-band voltage are obtainable.