Researchers create the world's smallest OLED pixel at 300x300 nm

Researchers from the Julius-Maximilians-Universität Würzburg (JMU) have managed to create the world's smallest OLED to date, at only 300 x 300 nm. To create such small pixels, the researchers developed a novel metallic contact that allows current injection into the OLED while simultaneously amplifying and emitting the generated light.

The researchers say that their OLED device, which emits orange light, is just as bright as a standard OLED with a size of 5x5 um. It is not clear whether there are real applications for such small OLED devices - perhaps in AR headsets, or in OLED based communication.

The researchers say that a key challenge in this research was the uneven distribution of currents in very small dimensions. In fact with very small OLED emitters, the light is emitted mainly from the corners of the device, and the resulting electric fields would generate strong forces that will mobilize the gold atoms on the connector into the OLED device. 

To solve this issue, the JMU researchers developed a structure that contains a newly introduced, specially manufactured insulation layer on top of the OLED device. The new layer leaves only a 200 nm diameter circular opening. The new layer blocks the currents that would have otherwise been injected into the edges and convers of the device.