High power ultrafast laser self-driven structuring of various conducting surfaces is pursued towards the production of arrays of sharp tips for efficient and durable cold electron emission applications.
Ultrafast Laser Micro- and Nano- processing
Display technology leads its way towards thinner self-luminus flat panels that will output high brightness and contrast image streams at scan rates fast enough to eliminate blurring effects of current LCD-TFT architectures. Tip-array cathodes emitting electrons towards fluorescent anode screens are pursued as a promising alternative. Sharp tips are necessary in order to minimize bias voltage and power consumption requirements. We try to either construct spike arrays on metals or semiconductors by ultra-fast laser treatment of their surfaces or deposit tip-structured films by pulsed-laser deposition, drop casting or spin coating techniques on various substrates. We modify parameters such as laser wavelength, pulse duration, pulse shape, pulse energy, repetition rate, number of pulses and the phase (liquid or gas) and chemistry of the environment during the process in order to find the best combination for each material. Post array treatment plays also an important role in these studies. Characterization comprises current-voltage tracing and stability – durability assessment of the electron emission of fabricated structures. Promising results have been already obtained for Si, SiC, Au /Cr coated and carbon nanotubes/nanowalls and graphne decorated Si spikes. On-going investigations involve graphene derivatives as well as inorganic nanostructures.
Prof. Emmanuel Kymakis and Prof. E. Koudoumas, Technological Educational Institute of Crete, Greece.
Prof. A. Zak and R. Tenne, Weizmann Insitute Weizmann Institute of Science, Rehovot Israel.
Prof. M. Chhowalla, Department of Materials Science and Engineering, Rutgers University.
Dr. Goki Eda, Department of Physics, National University of Singapore.
Prof. R. Giorgi, ENEA-Department of Physical Technology and Material, Research Centre of Casaccia, Italy.
- Free-standing graphene on microstructured silicon vertices for enhanced field emission properties
Stratakis E., Eda G., Yamaguchi,H. Kymakis E., Fotakis C., Chhowalla M., , Nanoscale, 4,3069-3074, 2012
- Nano-textured W shows improvement of thermionic emission properties
Barmina, E.V., Serkov, A.A., Stratakis, E., Fotakis, C., Stolyarov, V.N., Stolyarov, I.N., Shafeev, G.A., Applied Physics A, 106, 1-4., 2012
- Three-dimensional carbon nanowall field emission arrays
E. Stratakis, R. Giorgi, M. Barberoglou, Th. Dikonimos, E. Salernitano, N. Lisi, and E. Kymakis , Applied Physics Letters, 96, 043110, 2010
- Polymer-nanotube composite mats with improved field emission performance and stability
E. Stratakis, E. Kymakis, E. Spanakis, P. Tzanetakis and E. Koudoumas, Physical Chemistry Chemical Physics, 11, 703, 2009
- Ultraviolet laser structuring of silicon carbide for cold cathode applications
E. Spanakis, J. Dialektos, E. Stratakis, V. Zorba, P. Tzanetakis and C. Fotakis, Physica Status Solidi C, 5, 3309, 2008
- Field Emission properties of arrayed and continuous areas of laser fabricated Silicon microstructures
V. Zorba, E. Stratakis, E. Spanakis, D.G. Papazoglou, I. Zergioti, P.Tzanetakis and C.Fotakis, Journal of Nanoengineering and Nanosystems, 220, 143, 2007
- Silicon electron emitters fabricated by ultraviolet laser pulses
V. Zorba, P. Tzanetakis, C. Fotakis, E. Spanakis, E. Stratakis, D.G. Papazoglou, I. Zergioti, Applied Physics Letters, 88, 081103, 2006
Dr. Emmanuel Stratakis
Mr. Emmanouil Amargianitakis
Dr. Manolis Spanakis
Prof. Costas Fotakis
Prof. Panagiotis Tzanetakis