Growth kinetics in transition-metals ceramic compounds
Growth kinetics in transition-metal
Javier García Molleja
Nous imaginons pour vous les matériaux de demain
Where am I?
Postdoctoral researcher at Institut des Matériaux
Jean Rouxel (February 2013-February 2014).
Director: Pierre-Yves Jouan
-Centre National de la Recherche Scientifique
-Université de Nantes
Analyse, Modelisation (CEISAM)
Graduate in Physics by Universidad de Córdoba (Spain, July
Expertise in plasma physics and numerical simulation.
PhD degree by Universidad Nacional de Rosario (Argentina,
June 2007-March 2012).
Surface treatment of steels using plasmas with carbon or
nitrogen. Characterization and irradiation with high energy
Postdoctoral researcher at Instituto de Física de Rosario
(Argentina, May 2012-February 2013).
Deposition of ternary compounds on cutting blades and
Institut des Matériaux Jean Rouxel. Director: Guy Ouvrard.
It is an UMR institution (Centre National de la Recherce
Scientifique and Université de Nantes).
Six different research laboratories, including Plasma et
Couches Minces one. Director: Pierre-Yves Tessier.
So, what is a plasma?
Almost the 90% of visible matter in the universe
is under plasma condition (including stars,
stardust, nebulae, lightnings and the most part of
Historically, the plasma has been considered the
fourth state of the matter. Gases with high
energy (hot gases) may suffer ionization, so this
gas is composed by neutral particles, positive
ions and electrons.
If this system responds to electromagnetic fields,
it is called a plasma.
So, what is a plasma?
We can use plasma for
treatment of surfaces
To cover delicate things.
Commercial signals with
Or they are used as
Yes, I include our new
Yes, magnetrons have magnets and we use them to work
easily (not always) with plasmas.
Magnetrons confines plasma electrons and provoke a lot of
These positive ions (argon ions, generally) are attracted to
the cathode, place where there is a target made of a
material of interest (aluminum, chromium, nickel…).
The material is sputtered and these particles travel until
they reach a substrate, thus they deposit on it.
If the plasma contains reactive gases (nitrogen, oxygen…),
not only noble ones, is probable a reaction, making a new
Ok, a sketch of this magnetron sputtering
stable with different
We can play with
Working pressure is
very low: less than
100000 times the
pumps and avoid
Film deposition is analyzed under different
nitrogen concentrations in our plasma, different
working pressure, and different magnetronsubstrate distance.
Let’s complicate a bit more this stuff: what
happens if the power of the discharge is
Different working pressure is
relevant under high nitrogen
nitrogen provokes crystal
It is demonstrated that
oxygen is only a surface
In this case we only change oxygen percentage in
We are studying the growth kinetics, so it is
interesting to see how crystal structure is
changed with thickness.
And we ask ourselves if different bias (negative
voltage in the substrate to attract some ions) has
an important role or not.
Yes, we have structural
evolution with thickness,
and with bias in some
Variation with thickness:
substrate imposes internal
Variation with bias: ion
reached. After that, it shall
There is an influence of
oxygen content, there is
a distortion of crystal
Indeed, at same bias or
avoids some orientations,
so we can distinguish two
Synchrotron facility in Campinas (Brazil).
X-ray beam with high intensity and good properties.
Useful to measure in-situ thin film growth.
Understanding of nucleation processes, structural changes
Development of NiO (nickel oxide) with new
techniques, like HiPIMS.
Understanding of growth kinetics and residual
Application to solar cells: photovoltaic devices.
Theoretical study and experimental development
of Mott-Hubbard insulators with NiO in order to
apply in the field of microelectronics.
Elaboration of papers related to NiO and CrN
Improve the Nantes-Rosario relationship with
-Aluminum nitride growth in Campinas
-Preliminary work with metamaterials
Find a new job, a permanent position (university,
R&D company) if it is possible.