Efficient optoelectronic devices are multilayers structures, which is usually fabricated by means of vacuum deposition methods. Adaptation of cheap printing technology for fabrication of light emitting diodes (OLEDs) and photodiodes (PD) requires a different approach to the device structure, which should be possible simple.
Organic photodiodes are the class of light detectors which are now intensively investigated with an aim for applications in electronics. An important issue of the organic photodiodes is a high level of dark current density. Common practice aiming to reduce the dark current is the use of reversed structure of the device, where ITO electrode with modified reduced work function is used as the cathode. The effect of such modification will be presented through the improved photodetector work parameters.
In the case of OLEDs patterning the emission area is an important step in the process of OLED fabrication. Most often, the emission zone is determined by the overlapping region of the bottom and the top electrodes. Among many functional layers, an electron injection layer is one that plays a vital role in injection electrons from the cathode into the emissive or electron transport layers. The patterning of the emission area can be achieved by the specially selected interlayer, what will be presented on the example of simple structure of organic light emitting diode.