Ormosiles : a new class of materials for sensitive layers in the development of gas sensors

Organically modified silicates (ORMOSILes) can give a new starting point for the preparation or reactive layers. These noncrystalline solids are built up by a network of siloxane bonds (Si-O-Si) with functional organic groups connected by silicon carbon bonds. The properties of ORMOSILes can be tailored by choosing appropriate functional groups and reaction conditions, which will determine structure and microstructure (e.g. porosity). It is shown that the adsoprtion of gases on the surface of ORMOSIL layers change the electrical properties of interdigitated planar capcitor structures. Measurements with SO2, NH3, NO2 are reported