title: Ultrathin nickel oxide film as a hole buffer layer to enhance the optoelectronic performance of a polymer light-emitting diode.
abstract: In order to promote a polymer LED (PLED), we fabricated and introduced an ultrathin nickel oxide (NiO) buffer layer (<10 nm) between the indium tin oxide (ITO) anode and the poly (3, 4-ethylenedioxythiophene) hole injection layer in the PLED. The NiO buffer layer was easily formed on the ITO anode by electron-beam deposition of a nickel (Ni) metal source and an oxygen plasma treatment process. As a result, the PLED device with the NiO buffer layer on its ITO anode had the same turn-on voltage as conventional PLED devices without the NiO buffer layer, and the luminance of the PLED device with the NiO buffer layer was doubled, compared with the conventional PLED devices without the NiO buffer layer. Improvement of the optoelectronic performance of the PLED can be attributed to the increase of the current driven into the diode, resulting from the NiO buffer layer, which can enhance the hole injection and balance the injection of the two types of carriers (holes and electrons). Thus it is an excellent choice to introduce the NiO buffer layer onto the ITO anode of the PLED devices in order to enhance the optoelectronic performance of PLED devices.
authors.affiliation: Key Laboratory of Electroluminescent Devices of Guangdong Provincial Education Department, Institute of Optoelectronic Materials and Technology, South China Normal University, Guangzhou 510631, China.
authors.forename: Yongli
authors.initials: Y
authors.lastname: Wang
authors.forename: Qiaoli
authors.initials: Q
authors.lastname: Niu
authors.forename: Candong
authors.initials: C
authors.lastname: Hu
authors.forename: Wenjie
authors.initials: W
authors.lastname: Wang
authors.forename: Miao
authors.initials: M
authors.lastname: He
authors.forename: Yong
authors.initials: Y
authors.lastname: Zhang
authors.forename: Shuti
authors.initials: S
authors.lastname: Li
authors.forename: Lingzhi
authors.initials: L
authors.lastname: Zhao
authors.forename: Xin
authors.initials: X
authors.lastname: Wang
authors.forename: Jia
authors.initials: J
authors.lastname: Xu
authors.forename: Qiuxiang
authors.initials: Q
authors.lastname: Zhu
authors.forename: Sihai
authors.initials: S
authors.lastname: Chen