Fig. 1: Characterization of intermediate layers for vertically stacked full-color organic light emitting diodes (OLEDs).

a Schematic of full-color OLED with vertically stacked red (R), green (G), and blue (B). b Transmittance spectra for the Al₂O₃ (green solid line), and SiN_x (blue dashed line) layers, and scanning electron microscope (SEM) image (inset) of the SiN_x layer. Scale bar, 100 nm. c Current density (J)–voltage (V)–Luminance (L) characteristics, d Electroluminescence spectra of OLED with Al₂O₃ thin film encapsulation, and Al₂O₃/SiN_x passivation layer. OLED with Al₂O₃ (blue line with closed diamond for B, green line with closed triangle for G, and red line with closed square for R), and OLED with Al₂O₃/SiN_x (blue line with open star for B, green line with open down triangle for G, and red line with open circle for R). e Transmittance spectrum and SEM image (inset) of indium zinc oxide (IZO) intermediate electrode. Scale bar, 100 nm. f Atomic force microscope image of OLED/Al₂O₃/SiN_x/IZO. Scale bar, 1 μm.