Abstract Organic single crystals are often shown to have significantly improved optoelectronic properties over polycrystalline thin films such as exciton diffusivity and carrier mobility. There is growing interest in incorporating such crystals in organic electronics despite a number of challenges. In this work, the homoepitaxial vapor phase growth modes for 9,10-diphenylanthracene (DPA) homoepitaxy are mapped as a function of growth rate and temperature using in situ ultra-low current reflection high energy electron diffraction (RHEED), X-ray diffraction (XRD), and atomic force microscopy (AFM). Vapor phase deposition was performed on free-standing single crystal DPA substrates, which show clear Kikuchi patterns. At room temperature, a transition from Frank-Van der Merwe layer-by-layer growth to step-flow growth is observed as the deposition rate is decreased, while at lower temperatures a Stranski-Krastanov layer-plus-island growth is observed. This is the first demonstration of true step-flow growth from room temperature vapor phase deposition for organic semiconductors and is reminiscent of traditional semiconductor growth regimes. Accordingly, these results could lead to improved control over growth and doping of organic single crystals, and lead to enhanced single crystal organic optoelectronic applications.

中文翻译：

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9,10-二苯基蒽的同质外延生长

摘要 与多晶薄膜相比，有机单晶通常具有显着改善的光电性能，例如激子扩散率和载流子迁移率。尽管存在许多挑战，但人们对在有机电子产品中加入这种晶体越来越感兴趣。在这项工作中，使用原位超低电流反射高能电子衍射 (RHEED)、X 射线衍射将 9,10-二苯基蒽 (DPA) 同质外延的同质外延气相生长模式绘制为生长速率和温度的函数(XRD) 和原子力显微镜 (AFM)。在独立的单晶 DPA 基板上进行气相沉积，显示出清晰的菊池图案。在室温下，随着沉积速率的降低，观察到从 Frank-Van der Merwe 逐层生长到阶梯流生长的转变，而在较低温度下观察到 Stranski-Krastanov 层加岛生长。这是有机半导体室温气相沉积的真正阶梯流生长的首次演示，让人联想到传统的半导体生长方式。因此，这些结果可以改善对有机单晶的生长和掺杂的控制，并导致增强的单晶有机光电应用。这是有机半导体室温气相沉积的真正阶梯流生长的首次演示，让人联想到传统的半导体生长方式。因此，这些结果可以改善对有机单晶的生长和掺杂的控制，并导致增强的单晶有机光电应用。这是有机半导体室温气相沉积的真正阶梯流生长的首次演示，让人联想到传统的半导体生长方式。因此，这些结果可以改善对有机单晶的生长和掺杂的控制，并导致增强的单晶有机光电应用。