Gd-doping of HfO₂

Authors

Ihor Ketsman, University of Nebraska-LincolnFollow
Yaroslav B. Losovyj, University of Nebraska-LincolnFollow
Jinke Tang, University of WyomingFollow
Zhenjun Wang, University of Wyoming
M. L. Natta, University of Nebraska-Lincoln
Jennifer I. Brand, University of Nebraska-LincolnFollow
Peter A. Dowben, University of Nebraska-LincolnFollow

Date of this Version

1-19-2008

Comments

Published in Applied Surface Science (2008); doi:10.1016/j.apsusc.2008.01.060 Copyright © 2008 Elsevier B.V. Used by permission. http://www.sciencedirect.com/science/journal/01694332

Abstract

An increase in the density of states between the oxygen 2p bands and the Fermi level is seen with increasing Gd concentrations. In addition, for the Gd-doped HfO₂ films, the Gd 4f photoexcitation peak at 5.5 eV below the valence band maximum was identified using resonant photoemission. Electrical measurements show pronounced rectification properties for lightly-doped Gd:HfO₂ films on p-Si and for heavily-doped Gd:HfO₂ films on n-Si, suggesting a crossover from n-type to p-type behavior with increasing doping level. In addition, there is an increase in the reverse bias current with neutron irradiation.