Indium tin oxide (ITO) thin films have been deposited by rf magnetron sputtering on glass substrates at different substrate temperatures. The structural, electrical and optical properties of these films have been investigated to obtain optimum values for resistivity, optical transmittance and surface smoothness. The film deposited at a substrate temperature of 300 • C shows good conductivity, optical transmittance, crystallinity and surface smoothness. These ITO films were used to fabricate organic light emitting diodes (OLEDs). The dc current-voltage (I-V) studies on ITO/PEDOT:PSS/MEH-PPV/Al test structures show better rectifying behaviour on a smoother ITO substrate.

A series of novel arylvinyl-substituted phenanthroline derivatives have been synthesized and their applications as electron-transporting materials in organic light-emitting diodes (OLED’s) have been investigated. One particular derivative, namely, 2,9-bis(2-thiophen-2-ylvinyl)[1,10]phenanthroline shows significantly lower operating voltage than tris(8-quinolinolato)aluminum(III) (Alq3) and substantially higher lifetime than bathophenanthroline (BPhen).