TY - JOUR A1 - Hübert, Thomas A1 - Shimamura, Aki A1 - Klyszcz, Andreas T1 - Electrical Properties of Carbon Black and Ruthenium Dioxide Embedded Silica Films T2 - Journal of sol gel science and technology N2 - The electrical properties of sol–gel-derived films can be tailored by embedding conductive particles of ruthenium dioxide or carbon black in an insulating amorphous SiO2 silica matrix. The preparation process included an acid hydrolysis of tetraethoxysilane and methyltrimethoxysilane. Then alcohol solutions of ruthenium chloride or carbon black were added. Films of filler concentration up to 60 vol.% were prepared by dip coating and then dried and heat-treated at various temperatures up to 600_°C. The D.C. resistance of the films can be varied within the range of 109 to 10–2 OHgr sdot cm. A non-linear dependence on filler composition in the films was observed for both systems, which is explained by a modified percolation theory. A percolation threshold of 5.5 vol.% for SiO2-RuO2 or 50 vol.% for SiO2-C films, whereby the resistance drastically decreases, was determined. Moreover the temperature dependency of resistance and the current-voltage characteristics of the films can also be explained by this geometric model. PB - Kluwer Academic Publ. CY - Dordrecht KW - Sol-gel KW - Thin films KW - Carbon black KW - Ruthenium dioxide KW - Percolation phenomena PY - 2004 UR - https://opus4.kobv.de/opus4-bam/frontdoor/index/index/docId/6909 AN - OPUS4-6909 SN - 0928-0707 SN - 1573-4846 VL - 32 SP - 131 EP - 135 AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany