Global Journalist: Press freedom threatened in Eastern Europe

During this Jan. 24, 2008 show, Stuart Loory discusses with European journalists the causes and consequences of the press freedom setback several Eastern European countries have been facing, especially Bulgaria, Poland, Slovenia and Slovakia

Optical and electrical properties of F doped SnO2 thin films

A wide variety of commercial devices needs conducting/semiconducting metal oxide materials due to their unique combination of high optical transparency and high electrical conductivity. Moreover, induced defects within the host atomic arrangement are fairly responsible for their desirable optical and electrical properties. Therefore, studying the effect of doped ion is essential for better understanding of the behaviour of conducting/semiconducting metal oxides. In this context, influence of fluorine doping on optical and electrical properties of polycrystalline SnO2 thin films synthesized using sol-gel assisted spin coating method have been investigated in this work. The structural, optical and electronic analysis of pure and F doped SnO2 thin film indicates major effect of F doping concentration. Based on the electrical measurement these films show semiconducting nature with optical band gap in the range from 2.88 to 3.11 eV with increasing F concentration. These results suggest that F doped SnO2 thin films are suitable in field of advance electronic or nano-electronic device technology