A Light Scattering Layer for Internal Light Extraction of Organic Light-Emitting Diodes Based on Silver Nanowires

• Published in: ACS applied materials & interfaces Vol. 8; no. 27; pp. 17409 - 17415
• Main Authors: Lee, Keunsoo, Shin, Jin-Wook, Park, Jun-Hwan, Lee, Jonghee, Joo, Chul Woong, Lee, Jeong-Ik, Cho, Doo-Hee, Lim, Jong Tae, Oh, Min-Cheol, Ju, Byeong-Kwon, Moon, Jaehyun
• Format: Journal Article
• Language: English
• Published: United States American Chemical Society 13-07-2016
• Subjects: light extraction; silver nanowires; finite difference time domain; wrinkle structures; organic light-emitting diodes
• ISSN: 1944-8244; 1944-8252
• DOI: 10.1021/acsami.6b02924

We propose and fabricate a random light scattering layer for light extraction in organic light-emitting diodes (OLEDs) with silver nanodots, which were obtained by melting silver nanowires. The OLED with the light scattering layer as an internal light extraction structure was enhanced by 49.1% for the integrated external quantum efficiency (EQE). When a wrinkle structure is simultaneously used for an external light extraction structure, the total enhancement of the integrated EQE was 65.3%. The EQE is maximized to 65.3% at a current level of 2.0 mA/cm2. By applying an internal light scattering layer and wrinkle structure to an OLED, the variance in the emission spectra was negligible over a broad viewing angle. Power mode analyses with finite difference time domain (FDTD) simulations revealed that the use of a scattering layer effectively reduced the waveguiding mode while introducing non-negligible absorption. Our method offers an effective yet simple approach to achieve both efficiency enhancement and spectral stability for a wide range of OLED applications.