Sputter-patterned ITO-based organic light-emitting diodes with leakage current cut-off layers

We demonstrate the cost-effective fabrication of organic light-emitting diodes (OLEDs) using a sputter-patterned indium–tin-oxide (ITO). This scheme brings in a leakage current on the slope of the sputter-patterned ITO edges due to spike-like surface. To suppress it, we place thermally evaporated organic insulating molecules right on the ITO edges for preventing hole leakage, just below the aluminum (Al) cathode for blocking electron leakage, or both on the ITO edges and below the Al cathode. It is demonstrated that blocking off both hole- and electron-leak pathways (via the spikes) is highly desired to enhance the current efficiency and lifetime of the sputter-patterned ITO-based OLEDs.

The OLED structure with the double (HCl and ECL) insulating layer and measured luminance as a function of operational time at an initial luminance of 1000 nit.Figure optionsDownload as PowerPoint slideHighlights
► We demonstrate the cost-effective fabrication of sputter-patterned ITO-based OLEDs.
► This scheme brings in a leakage current on the ITO edges due to spike-like surface.
► We found that blocking off both hole- and electron-leak pathways is highly desired.
► OLEDs based on this scheme showed higher current efficiency and longer lifetime.