Photolithographic patterning of subwavelength top emitting colloidal quantum dot based inorganic light emitting diodes on silicon

The combination of lithographic patterning and nanostamping methods makes it possible to accurately define diffraction-limited multicolor (wavelengths 560–620 nm) light sources on a silicon substrate. We demonstrate a postprocessing technique that utilizes standard photolithography process to pattern the cathode of top emitting diode. Correlation of electroluminescence, photoluminescence, and atomic force microscopy topography showed that the emission region is well defined through the robust multiscale patterning techniques, with the fineness of the emitting area mainly limited by the point spread function of the observing microscope.