Elektrisch leitende ZnO enthaltende Schichten auf Substraten und Verfahren zu deren Herstellung
An electronic conductor layer formed of transparent nano-crystalline ZnO on a substrate is new. Preferably, the layer is 0.4-3 mu m thick, has a resistivity of 9 multiply 10-1 - 1 multiply 10-3 Omega .cm and is doped especially with aluminium. Also claimed is production of an electrically conductive ZnO layer on a substrate by applying a nano-particle-containing ZnO sol and heat treating to form a at least 0.4 mu m thick layer. Preferably, the ZnO sol is synthesised from a zinc alkoxide precursor by base-catalysed hydrolysis, aluminium preferably being added by using an aluminium-containing zinc alkoxide precursor or by Al(sec. BuO)3 addition to the ZnO sol. USE - In the electronics industry or in various sensors. ADVANTAGE - The ZnO or Al-doped ZnO layer is optically transparent (more than 90% transmission at 450-1200 nm), nano-porous and electrically conductive (resistivity = 400-3000 Omega per square for ZnO and 20-50 Omega per square for Al-doped ZnO), can be formed to a relatively large thickness and allows desirable modification of its electrical and optical properties by doping and subsequent infiltration.
DE 1997-19719162 A: 19970506