Department of Materials Science and Engineering, Yonsei University, Seoul 120-749, Republic of Korea.
ACS Appl Mater Interfaces. 2013 May;5(9):3650-5. doi: 10.1021/am400140c. Epub 2013 Apr 17.
In this work, we investigated the use of a homogeneous Al-doped zinc oxide (AZO) buffer layer to improve the performance of an organic light-emitting diode (OLED) device fabricated on an AZO anode. For this, 10-nm-thick AZO buffer layers with Al doping concentrations of 3.1, 4.1, and 5.1 at % were grown on 140-nm-thick AZO anode films containing 2.1 at % Al by atomic layer deposition. The electrical resistivity of the AZO anode with a homogeneous AZO buffer layer decreased with an increase in Al doping concentration up to 4.1 at %; however, the resistivity increased at higher doping concentrations in the AZO buffer layer. On the other hand, the work functions of the AZO anode with the AZO buffer layer containing various Al doping concentrations gradually increased with an increase in Al doping concentration from 3.1 to 5.1 at %. Therefore, the best film properties were obtained for an AZO anode with an AZO buffer layer containing 4.1 at % Al, and the work function value for this film was 4.64 eV. The highest luminance and current efficiency values were optimized to be 20290 cd/m(2) and 13.4 cd/A, respectively, with the OLED device composed of a DNTPD/TAPC/Bebq2:10% doped RP-411/Bphen/LiF/Al structure on an AZO anode with an AZO buffer layer containing 4.1 at % Al.
在这项工作中，我们研究了使用同质掺铝氧化锌 (AZO) 缓冲层来改善在 AZO 阳极上制备的有机发光二极管 (OLED) 器件的性能。为此，通过原子层沉积在含有 2.1 at%Al 的 140nm 厚 AZO 阳极薄膜上生长了 3.1、4.1 和 5.1 at%Al 掺杂浓度的 10nm 厚 AZO 缓冲层。具有同质 AZO 缓冲层的 AZO 阳极的电阻率随 Al 掺杂浓度的增加而降低，最高可达 4.1 at%；然而，在 AZO 缓冲层中存在更高的掺杂浓度时，电阻率会增加。另一方面，具有含有各种 Al 掺杂浓度的 AZO 缓冲层的 AZO 阳极的功函数随着 Al 掺杂浓度从 3.1 到 5.1 at%的增加而逐渐增加。因此，AZO 阳极与含有 4.1 at%Al 的 AZO 缓冲层的最佳膜性能，并且该膜的功函数值为 4.64eV。在包含 4.1 at%Al 的 AZO 缓冲层的 AZO 阳极上制备的 OLED 器件中，当使用 DNTPD/TAPC/Bebq2:10%掺杂 RP-411/Bphen/LiF/Al 结构时，获得了最高亮度和电流效率值，分别为 20290cd/m²和 13.4cd/A。
