Interface Energy Alignment of Atomic-Layer-Deposited VOx on Pentacene: an in Situ Photoelectron Spectroscopy Investigation
Interface Energy Alignment of Atomic-Layer-Deposited VOx on Pentacene: an in Situ Photoelectron Spectroscopy Investigation
复制标题
并五苯上原子层沉积的 VOx 的界面能量排列：原位光电子能谱研究
DOI：
10.1021/acsami.6b12832
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发表时间：
2017
影响因子：
9.5
通讯作者：
Wang Xinwei
中科院分区：
文献类型：
--
作者：
Zhao Ran;Gao Yuanhong;Guo Zheng;Su Yantao;Wang Xinwei
超薄原子层沉积（ALD）氧化钒（VOx）中间层最近已被证明用于显著降低有机电子器件中的接触电阻（Adv.Funct. Mater.2016，26，4456）。在此，我们提出了原位光电子能谱研究（包括X射线和紫外光电子能谱）的ALD VOX生长在并五苯，以了解ALD VOX夹层的作用，改善接触电阻。原位光电子能谱表征使我们能够监测VOx的ALD生长过程，并跟踪生长过程中的功函数，并五苯HOMO能级和VOx缺陷态的演变。发现在第一个20个ALD循环中，并五苯上的初始VOx生长部分延迟。在ALD之后，下面的并五苯层基本上是完整的。发现ALD VOx包含从低于费米能级0.67 eV开始的高密度缺陷态，并且这些缺陷态的能级与并五苯的HOMO能级极好地对准，这因此允许这些VOx缺陷态在接触界面处提供有效的空穴注入路径。
Ultrathin atomic-layer-deposited (ALD) vanadium oxide (VOx) interlayer has recently been demonstrated for remarkably reducing the contact resistance in organic electronic devices (Adv. Funct. Mater.2016,26, 4456). Herein, we present an in situ photoelectron spectroscopy investigation (including X-ray and ultraviolet photoelectron spectroscopies) of ALD VOxgrown on pentacene to understand the role of the ALD VOxinterlayer for the improved contact resistance. The in situ photoelectron spectroscopy characterizations allow us to monitor the ALD growth process of VOxand trace the evolutions of the work function, pentacene HOMO level, and VOxdefect states during the growth. The initial VOxgrowth is found to be partially delayed on pentacene in the first ∼20 ALD cycles. The underneath pentacene layer is largely intact after ALD. The ALD VOxis found to contain a high density of defect states starting from 0.67 eV below the Fermi level, and the energy level of these defect states is in excellent alignment with the HOMO level of pentacene, which therefore allows these VOxdefect states to provide an efficient hole-injection pathway at the contact interface.