Dr. A. C. Cefalas is director of
research at NHRF. He received his B.SC in Physics from Athens University
in 1978, and the MSc and PhD from Manchester University UK on Laser
Physics and Nonlinear Optics in 1979 and 1983 respectively. He is
the head of the Short Light Wavelengths and Nano-applications Laboratory
at this establishment since 1983, which is the main European Laboratory
for "157nm technology". He is the author of over 90 scientific
papers in high reputed international journals and he had participating
in more than 70 international conferences on VUV laser physics and
light-matter intraction, in many of them as an invited speaker.
A broader description of his research interests are described as"
Development of advanced functional materials and methods for nano-applications
assisted by short wavelength and laser light at 157nm". He
is a member of the Optical Society of America (OSA) and the international
Society on Optical Engineering (SPIE) and has been actively involved
in many European Research Projects since 1986.
RESEARCH ACTIVITIES AND NANO-APPLICATIONS
A broader description of current
research activities and nano-applicationscould be embedded under
the general title "Advanced functional materials and methods
for nano-applications assisted by short wavelength and laser light
at 157nm". The research is directed towards the following directions:
1) Development of novel wide band
gap optical crystals doped with trivalent rare-earth ions. Assessment
of their potential use for VUV applications ( passive or active
optical elements) is directly related to the evaluation of their
optical and electronic properties in the vacuum ultraviolet region
of the spectrum (100-200nm). Laser induced fluorescence and VUV
absorption spectroscopy were used to identify the electronic energy
levels of the 4fn-15d electronic configuration of the
trivalent rare earth ions.
2) Evaluation of high resolution
sensitive polymeric materials for X-UV (30-100 nm) and VUV (100-180
nm) lithographic applications. The mass spectroscopic and the VUV
laser induced fluorescence techniques are the main analytical tools
for investigating polymer photo-dissociation dynamics. This in its
turn, determines their potential use as high resolution photo-resistive
materials for 157nm lithographic applications. Photo-resists supplied
by IMEL Demokritos, have been evaluated at 193, 157 and 13.6 nm.
3) Demonstration of functional quantum
properties of mesoscopic systems. Small size agglomerations of metallic
character, clearly demonstrate the basic quantum ON-OFF switching
operation in the molecular level.
4) Magnetic interactions in nano-composite
films fabricated by pulsed laser deposition at 157 nm. Films fabricated
with this method have enhanced magnetic properties in comparison
to other techniques.
SURFACE TREATMENT OF MATERIALS
AT 157 nm- HIGH RESOLUTION MICROSCOPY
5) Imaging of biological specimens
in vivo on advanced functional polymeric materials, where details
of DNA and RNA structures are revealed with resolution better than
10nm. This is achieved by applying Laser Plasma Single Shot Soft
X-Ray Contact Microscopy technique (SXRCM), The successful application
of biological imaging implies the development of suitable photoresists,
which should be high resolution, sensitive with grey scale capabilities.
6) Identification of structural
damage of DNA crystals and bases on the molecular level by advanced
7) Micro-fabrication of DNA chips
at 157 nm.
8) Antifoxing preservation of historic
paper with laser light at 157 nm.
ANTICORROSSION ENERGY SAVING
9) Application of molecular technologies
for anti-corrosion and energy saving problems. Successful application
of the method involves control of nanocrystallization by physical
methods, such as control of scalling by magnetic fileld and turbulent