A synchrotron-based photoemission study of the MoO3∕Co interface.
The electronic structures at the MoO(3)∕Co interface were investigated using synchrotron-based ultraviolet and x-ray photoelectron spectroscopy. It was found that interfacial chemical reactions lead to the reduction of Mo oxidation states and the formation of Co-O bonds. These interfacial chemical reactions also induce a large interface dipole, which significantly increases the work function of the cobalt substrate. In addition, two interface states located at 1.0 and 2.0 eV below the Fermi level are identified. These two states overlap at film thickness of between 2-4 nm, which suggests the MoO(3) intermediate layer may facilitate ohmic charge transport.
Department of Physics, National University of Singapore, 2 Science Drive 3, Singapore 117542, Singapore.
Yu-Zhan
YZ
Wang
Ming
M
Yang
Dong-Chen
DC
Qi
Shi
S
Chen
Wei
W
Chen
Andrew T S
AT
Wee
Xing-Yu
XY
Gao
D003035:Cobalt / Q000737:chemistry*; D004583:Electrons; D008982:Molybdenum / Q000737:chemistry*; D010084:Oxidation-Reduction; D010087:Oxides / Q000737:chemistry*; D056951:Photoelectron Spectroscopy; D013056:Spectrophotometry, Ultraviolet; D017356:Synchrotrons
D010087:Oxides; C082290:molybdenum trioxide; D003035:Cobalt; D008982:Molybdenum