Hu Zheng, Turner C Heath
Department of Chemical and Biological Engineering, University of Alabama, Tuscaloosa, Alabama 35487, USA.
J Phys Chem B. 2006 Apr 27;110(16):8337-47. doi: 10.1021/jp060367b.
We present a density functional theory (DFT) study of the initial surface reactions of TiO2 deposition onto a SiO2 substrate using atomic layer deposition (ALD). The precursors for the deposition process were chosen to be TiCl4 and H2O, and several cluster models were used for the SiO2 substrate. We predict the activation barriers, transition states, and reaction pathways of the surface reactions, and we investigate the effect of surface heterogeneity (such as the presence of siloxane bridges) on the reactivity of the SiO2 surface. Our study suggests that the concentration and arrangement of different reactive groups on the substrate will strongly dictate the process of film growth during ALD, including the film morphology and the growth rate.
我们展示了一项关于使用原子层沉积（ALD）在SiO₂衬底上沉积TiO₂的初始表面反应的密度泛函理论（DFT）研究。沉积过程的前驱体选择为TiCl₄和H₂O，并使用了几种簇模型来模拟SiO₂衬底。我们预测了表面反应的活化能垒、过渡态和反应路径，并研究了表面非均质性（如硅氧烷桥的存在）对SiO₂表面反应活性的影响。我们的研究表明，衬底上不同反应基团的浓度和排列将强烈决定ALD过程中的薄膜生长过程，包括薄膜形态和生长速率。
