Evgueni Chagarov, Kasra Sardashti, et al.
Journal of Chemical Physics
We describe an in situ method for measuring the band bending of Si substrates in complex metal-oxide-semiconductor systems using femtosecond pump-probe photoelectron spectroscopy. Following deposition of metal layers (Pt, Re, or Re oxide) on the high- k dielectric HfO2, measurement of the band bending in the underlying Si provides a direct determination of the location of the Fermi level within the Si band gap at the Si-dielectric interface. Changes in the Fermi level with post-deposition anneals and oxygen exposure were correlated with valence and core photoelectron spectroscopy as well as capacitance-voltage measurements. These studies illuminate the roles that gate metal work function, modified by metal induced gap states and defects within the oxide, such as oxygen vacancies, play in defining the location of the Fermi level in metal-oxide-semiconductor structures. © 2005 American Institute of Physics.
Evgueni Chagarov, Kasra Sardashti, et al.
Journal of Chemical Physics
Richard Haight, Alfred Wagner, et al.
Lasers and Applications in Science and Engineering 2005
Talia S. Gershon, Kasra Sardashti, et al.
Acta Materialia
Hulling Shang, Jack O. Chu, et al.
IEDM 2004