Full Color Quantum Dot Light-Emitting Diodes Patterned by Photolithography Technology

摘要

Photolithography is a high resolution and mature patterning technique which has been widely used in semiconductor industry. For display application, a pixel consists of red (R), green (G) and blue (B) side-by-side sub-pixels, which thereby requires a high resolution patterning of the light-emission layers. In this work, photolithography is used to fine pattern the quantum dot (QD) light-emitting layers. To prevent the QDs being washed off during the lift-off process, the ZnMgO layer is treated by the hydrophobic material hexamethyldisilazane (HMDS). With HMDS treatment, the adhesion between the QDs and the ZnMgO is effectively improved. As a result, side-by-side RGB QD with pixel size 30 μm × 120 μm is successfully achieved. After patterning, the R, G and B QLEDs exhibit a maximum current efficiency of 11.6 cd/A, 29.7 cd/A and 1.5 cd/A, respectively.