| CZECH NANO TEAM | Physics of Nanostructures and Nanotechnologies

• Optical and photoelectrical spectroscopy of thin films
• Electronic defects in solids
• CVD diamond: technology and characterization
• Nanocrystalline diamond
• Photovoltaic solar energy conversion (thin film silicon and polymer solar cells)
• The supervisor of PhD and MS Diploma students from Prague University and Czech Technical University
• Publications: Author or co-author of more than 100 scientific publications, over 800 citations.

Selected study stays abroad:

• In 1969-70 MS degree at Northwestern University, Evanston, Ill., USA
• In years 1988-2004 about 2 years spent at Neuchatel University and EPFL, Lausanne, Switzerland
• In years 1988-2004 about 1 year at NREL, Colorado and Princeton University, NJ, USA

Selected projects:

• Teaching and working on international projects of Czech-US collaboration and EC 4th, 5th and 6th Framework Projects
• Since 2000 provides training within the European Research Training Network on CVD diamond
• 2000-2004 “Doped diamond devices and sensors”
• 2004-2008 “Diamond research on interfaces for versatile electronics”.

Selected publications from last 5 years:

• M. Vaněček, R. Kravets, A. Poruba, J. Rosa, M. Nesládek, S. Koizumi: Fourier transform photocurrent spectroscopy of dopants and defects in CVD diamond, Diamond and Related Materials 12, 521-5 (2003)
• M. Nesládek, K. Haenen, M. Vaněček: Optical properties of CVD diamond, Chapter 7 in book Thin-Film Diamond I, eds. Ch. Nebel and J. Ristein, in series “Semiconductors and Semimetals”, vol. 76, part A, Academic Press, pp. 325-377 (2003)
• V. Mortet, A. Kromka, R. Kravets, J. Rosa, V. Vorlíček, J. Zemek, M. Vaněček: Investigation of diamond growth at high pressure by microwave plasma chemical vapor deposition, Diamond and Related Materials 13 604-9 (2004)
• R. Kravets, M. Vaněček, C. Piccirillo, A. Mainwood, M.E. Newton: A quantitative study of the boron acceptor in diamond by Fourier-transform photocurrent spectroscopy, Diamond and Related Materials 13, 1785-90 (2004)
• V. Mortet, J.D. Haen, J. Potměšil, R. Kravets, I. Drbohlav, V. Vorlíček, J. Rosa, M. Vaněček: Thin nanodiamond membranes and their microstructural, optical and photoelectrical properties, Diamond and Related Materials (2005) in print.

Group members:

R. Kravets, Z. Poláčková, A. Poruba, J. Potměšil, Š. Potocký, Z. Remeš, J. Rosa, M. Vaněček

(and foreign post-docs from European RTN: A. Kromka, V. Mortet and K. Johnston)

Main Research Subjects:

• Nanocrystalline diamond thin films have been deposited on silicon and other substrates. Nucleation mechanism has been studied on a microscopic level, with a goal to reach 1012 nuclei/cm2 on a large area and to understand the nucleation mechanism. Bias enhanced nucleation and nucleation with diamond nanopowder (5 nm particles) has been used.
• Thin films of nanodiamond and ultra-nanodiamond has been deposited, with thickness of 70-2000 nm.
• The goal is to control the grain size, grain surface and the electronic properties. We study structural and electronic properties of these new materials by AFM, SEM, XRD and Raman scattering. For the electronic structure we apply luminescence and several optical, photothermal and photoconductive methods, as Fourier-transform photocurrent spectroscopy, FTPS.
• Our goal is determination of the density of gap states, as a function of grain size and nature of the grain surface. This could help us to explain peculiar transport properties of ultra-nanodiamond.
• Another goal is bio-functionalization of nanodiamond surface and research on stability of such surface. We will deposit nanodiamond films of a different grain size for DNA biochips and ion sensitive field effect transistors.

Selected Specific Equipment:

• MW PE CVD (microwave plasma enhanced chemical vapor deposition) apparatus by Aixtron, Aachen, Germany, substrate size up to 2 inches, upgraded with bias enhanced nucleation, together with growth and plasma monitoring in situ.
• FTPS (Fourier transform photocurrent spectroscopy) setup, based on Nicolet Nexus FTIR spectrometer, Stanford Research Systems and Keithley electronics and Oxford instruments cryostat.