中文摘要：

采用密度泛函方法研究了以TaCl5和H2O作为前驱体在硅表面原子层沉积（ALD）Ta2O5的初始反应机理．Ta2O5的原子层沉积过程包括两个连续的“半反应”，即TaCl5和H2O“半反应”．两个“半反应”都经历了一个相似的吸附中间体反应路径．通过H钝化和羟基预处理硅表面反应能量的比较发现，TaCl5在羟基预处理硅的表面反应是热力学和动力学都更加有利的反应．另外，从能量上看，H2O的“半反应”不容易向生成产物的方向进行．

英文摘要：

The surface reaction mechanism of atomic layer deposited （ALD） Ta2O5 on silicon surfaces was studied via density functional theory. The ALD process is designed into two sequential half-reactions, i. e. , TaCl5 and HE O half-reactions. Both of them proceed through an analogous trapping-mediated mechanism. By comparing with the reactions of TaCl5 on the H-terminated silicon surfaces, we find that it is both kinetically and thermodynamically more favorable for the reactions of TaC15 on the hydroxylated silicon surfaces. In addi- tion, we also find that it is energetically unfavorable for the H2O half-reactions.