Seminars Archive
Alexei Barinov
Abstract
Monday, March 19, 2001, 10:00
Seminar Room, ground floor, Building "T"
Sincrotrone Trieste, Basovizza
Spectromicroscopy of metal/GaN interfaces: surface reactions, electronic
structure and heterogeneity.
Alexei Barinov
(Sincrotrone Trieste & RRC Kurcharov Institute)
ABSTRACT
The evolution of the local composition and electronic properties of
Au, Ni and Ti/GaN interfaces at room temperature and after annealing has
been studied with scanning photoemission microscopy (SPEM) with lateral
resolution of 100 nm. One of the motivations for these studies was to demonstrate
the potential of SPEM to probe the chemical and structural specifics of
the M/S interface and to correlate them to the local band bending at the
surface. In our investigations special attention was paid to the effect
of the defective structure of the GaN epilayers grown on different substrates
on the uniformity of the Me/GaN interfaces. In all cases the lateral chemical
inhomogeneities, developed with the onset of chemical reaction, were related
to the presence of defects in the GaN epilayes. An important finding is
that despite strong chemical and structural heterogeneity negligible fluctuations
in the band bending are observed. The possible reasons for this insensitivity
of the band bending to the microscopic interface morphology effect will
be discussed.
