论文标题
从头开始,将各向异性合金融合到Si(001)表面
An ab initio approach to anisotropic alloying into the Si(001) surface
论文作者
论文摘要
采用密度功能理论计算,我们探索了共同沉积的银和依赖原子的竞争合金的初始阶段。特别是,我们确定了各自的吸附位置和利用它们在二聚体重建硅表面扩散的激活屏障。此外,我们开发了一种生长模型,该模型正确地描述了硅二聚化和C型缺陷的存在,从而正确描述了扩散机制和硅形态。基于表面动力学蒙特卡洛模拟,我们检查了双金属吸附的动力学,并详细介绍了温度对AG-IN合金亚层生长的影响。对Adatom迁移的仔细检查清楚地表明Ag和原子的有效成核,然后形成正交原子链。我们表明,外延双囊的生长可能有可能通过正交的单金属行以各向异性二维晶格的形式导致ADATOM的异国情调下降。我们认为,这种情况变得有利在室温之上,而我们的数值结果被证明与实验发现一致。
Employing density functional theory calculations we explore initial stage of competitive alloying of co-deposited silver and indium atoms into a silicon surface. Particularly, we identify respective adsorption positions and activation barriers governing their diffusion on the dimer-reconstructed silicon surface. Further, we develop a growth model that properly describes diffusion mechanisms and silicon morphology with the account of silicon dimerization and the presence of C-type defects. Based on the surface kinetic Monte Carlo simulations we examine dynamics of bimetallic adsorption and elaborate on the temperature effects on the submonolayer growth of Ag-In alloy. A close inspection of adatom migration clearly indicates effective nucleation of Ag and In atoms, followed by the formation of orthogonal atomic chains. We show that the epitaxial bimetal growth might potentially lead to exotic ordering of adatoms in the form of anisotropic two-dimensional lattices via orthogonal oriented single-metal rows. We argue that this scenario becomes favorable provided above room temperature, while our numerical results are shown to be in agreement with experimental findings.