Electroluminescence in thin films

The three most important technologies for future display applications where electroluminescence (EL) in thin films is used for light generation are discussed. These technologies are firstly, Alq- and PPV-based organic light emitting diodes (LED); secondly, inorganic a-SiC LED and thirdly, ac-driven thin film electroluminescent devices based on II-VI compounds. The last of these is of the high-field EL-type whereas the first two utilise low-field injection type EL. The basic principles and the current status of the respective technologies are summarised. Recent developments in ac thin film electroluminescence for full colour display applications are emphasised.