Compound tin dioxide-tin acetylacetonate based sensors prepared by pulsed laser deposition

Tin dioxide is the most widely used material for gas sensors utilising change of surface conductivity. The surface of some organic substances also exhibits an ability to enter into reversible chemical reactions with gases. The principle of conductivity change is in the high polarizability of delocalized /spl pi/-electrons in the system of conjugated double bonds. Metal complexes of acetyl-acetone (MeAcAc) are rich in delocalized electrons and in combination with semiconductive tin dioxide are apparently active. The addition of SnAcAc increases sensor sensitivity, decreases working temperature and also leads to higher porosity of the active layer. The pulsed laser deposition (PLD) method can be used for deposition of both organic and inorganic substances. It retains the original chemical composition and enables the layer thickness to be controlled. The properties of sensors were measured by DC- and AC- measurements. The paper also presents AC-sensitivity based on current-voltage phase shift.