Top-emitting red, green and blue organic light-emitting devices with CdSe/ZnS quantum dots down-conversion films

Top-emitting devices have the potential to achieve high aperture ratio of 100%, and thus it is very important for high-quality OLED displays. However, traditional fabrication methods used for achieving red, green and blue(RGB) OLED display are complicated and difficult, and spectral stability of such RGB OLEDs is always poor as time goes on. In this paper, to achieve color-stable RGB OLEDs, red and green quantum dots down-conversion films with microstructure are prepared by integrating CdSe/ZnS quantum dots into polymethyl methacrylate and using transfer imprint process 7 and then they are combined with efficient top-emitting blue OLED and color filters to achieve RGB emission using the same organic functional layers. RGB OLEDs exhibit a maximum current efficiency of 3.6, 21.9 and 10.6 cd/A, respectively, and their chromaticity coordinates are (0.70, 0.30), (0.24, 0.62) and (0.10, 0.20), respectively. Spectra and chromaticity coordinates of RGB OLEDs are almost invariable under different voltages, and emission of such RGB OLEDs also show excellent angle stability. This method used for realizing full-color OLED has the advantages of simple fabrication technique and low cost, and thus has broad development prospects.