Classical nucleation theory applied to molecular orientations in vapor-deposited organic thin films
Classical nucleation theory applied to molecular orientations in vapor-deposited organic thin films
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经典成核理论应用于气相沉积有机薄膜中的分子取向
DOI：
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发表时间：
2005
期刊：
影响因子：
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通讯作者：
R. Akiyama
中科院分区：
文献类型：
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作者：
A. Kubono;R. Akiyama
根据各向异性成核的经典成核理论，解释了各种线性长链化合物物理气相沉积过程中的分子取向机制。在这个模型中，考虑了表面能的各向异性，并假定初始小核具有两个基本取向(法向和横向)，并在热能的作用下反复解离。计算了各取向的成核临界能，作为体系化学势变化的函数。计算结果与实际观察到的长链分子在各种化学势变化下的取向现象相似，即较高的衬底温度和/或较低的沉积速率导致较高的法向取向度/S。
Molecular orientational mechanism during physical vapor deposition of various linear long-chain compounds has been interpreted on the basis of a classical nucleation theory modified for the anisotropic nucleus formation. In this model, the anisotropy of the surface energy is considered, and initial small nuclei with two fundamental orientations (normal and lateral) are assumed to be formed and dissociated repeatedly by the thermal energy. The critical energy of nucleus formation for each orientation is calculated as a function of the chemical-potential change of the system. The calculated results are similar to those observed for actual orientational phenomena of long-chain molecules at various chemical-potential changes; i.e., a higher substrate temperature and/or a lower deposition rate result/s in a higher degree of normal orientation.