CAJ | 학술논문

研究了三氧化钼(MoO3)薄层作为有机电致发光器件空穴注入层的器件性能和注入机制.发现1 nm厚度下发光器件性能最佳,器件的最大电流效率比对比发光器件的最大电流效率提高1.6倍.器件的电容曲线表明MoO3薄层能有效提高空穴载流子的注入,多数载流子开始注入的拐点大约降低了9 V.单空穴载流子电流曲线说明MoO3器件的电流注入是空间电荷受限电流注入机制,MoO3使阳极界面处形成欧姆接触,而对比器件的电流注入是陷阱电荷受限电流注入机制.器件的光伏曲线进一步说明器件性能的提高是由于MoO3层能使阳极界面能级分布发生改变,1 nm MoO3厚度下器件的内建电势从对比器件的0.25 V提高到了0.8 V,有效降低了空穴注入势垒,提高了器件性能,但过厚的MoO3层由于增加了器件的串联内阻,会导致器件性能降低.
연구료삼양화목(MoO3)박층작위유궤전치발광기건공혈주입층적기건성능화주입궤제.발현1 nm후도하발광기건성능최가,기건적최대전류효솔비대비발광기건적최대전류효솔제고1.6배.기건적전용곡선표명MoO3박층능유효제고공혈재류자적주입,다수재류자개시주입적괴점대약강저료9 V.단공혈재류자전류곡선설명MoO3기건적전류주입시공간전하수한전류주입궤제,MoO3사양겁계면처형성구모접촉,이대비기건적전류주입시함정전하수한전류주입궤제.기건적광복곡선진일보설명기건성능적제고시유우MoO3층능사양겁계면능급분포발생개변,1 nm MoO3후도하기건적내건전세종대비기건적0.25 V제고도료0.8 V,유효강저료공혈주입세루,제고료기건성능,단과후적MoO3층유우증가료기건적천련내조,회도치기건성능강저.
An efficient hole-injection contact was achieved for organic light-emitting diodes (OLEDs) based on molybdenum oxide (MoO3) as the buffer layer on indium tin oxide. The significant effect of MoO3 is that the devices show low operational voltage and high electroluminescence efficiency in a wide range of MoO3 thickness. The device with a 1 nm-thick MoO3 layer shows the best performance, the current efficiency is enhanced by 1.6 times by comparing with the control device. Capacitance-voltage measurement demonstrated that hole injection is enhanced in low operational voltage through the addition of MoO3. Results of the hole-only devices revealed that ohmic hole injection is formed at ITO/MoO3/NPB interface. Photovoltaic measurements confirmed that the improved hole injection is due to the reduction of barrier height, which is resulted from the addition of transition metal oxide.