钽基体上铜薄膜微观结构的分子动力学模拟

The microstructure of copper films on tantalum

运用分子动力方法模拟了铜薄膜在钽（100）及（111）基体上沉积过程。结果表明沉积过程中铜薄膜的晶格位向取决于钽基体的晶格位向．在钽（100）面上，铜薄膜在不同的温度下分别沿（111）或（110）面生长，所形成的晶界与住错沿着薄膜的生长方向发展，薄膜表面的粗糙度与沉积温度有关，低温时表面粗糙度较大。而在钽（100）面上，铜薄膜的外延生长面为（100）面，位错沿（111）面分布，并只存在于界面附近，在铜薄膜的内部仅有少量的点缺陷，薄膜表面粗糙度较小并与沉积温度无关。

The growth of copper films on fiat （100） and （111） tantalum surfaces has been studied using molecular dynamics simulations. The results show that the growth process is sensitive to the surface type of the tantalum substrate. On the （100） tantalum surface, copper preferentially grows into （111） or （110） surfaces depending on the growth temperature. Defects such as grain boundaries and dislocations develop along the growth direction and significant surface roughness forms at low temperatures. On the （111） tantalum surface, copper preferentially grows into （100） surface. Fewer defects are formed and no column structure is observed on this surface. The surface roughness is also found to be small and relatively insensitive to the growth temperature.