The formation of interfaces between magnesium (Mg) and the organic molecular semiconductor tris(8-hydroxy-quinoline) aluminum is studied via ultraviolet photoemission spectroscopy. The morphology and electronic structure of and interfaces are compared. The energy of the molecular levels is determined in both cases with respect to a reference Fermi level as a function of interface formation. The difference in injection characteristics between the two interfaces is examined in terms of differences in interface morphology and of electronic gap states induced by the diffusion of Mg at the interface.
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© 1998 American Institute of Physics.
1998
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