TWO-COLOR THI-FILM ELECTROLUMINESCENCE WITH SPATIALLY SELECTIVE ACTIVATOR DOPING.

Because ac thin-film electroluminescent (ACTFEL) devices are transparent, two or more complete structures with emissions at different wavelengths may be placed behind one another to display two or more colors. It is demonstrated that more than one color may also be achieved in a single structure using a laser chemical vapor depostiion (LCVD) process for the spatially selective deposition of Mn. The device has a ZnS:TbF//3 active layer with high resolution spatially modulated Mn doping. A color switching phenomenon was observed and explained that suggests the possibility of electrical color modulation.