Dynamic Scaling Study of Thin Films in electrodeposition Growth Using AFM

(1)电沉积中的三维生长我们用原子力显微镜研究了脉冲电流电沉积镍表面的结垢特性。对于中间时间段i^z&lt；L^z，表面生长呈现反常的动态标度行为，表征为局域粗糙度指数ζ；lt；loc&gt；、整体标度指数ζ和动态指数z，其中i和L表示窗口长度和系统大小。镍表面的局部界面宽度导致ζ_lt；loc&gt；=1，全局标度指数ζ=2.8，动态指数z=4.1。(2)电沉积中的二维生长用原子力显微镜研究了在(100)Ni衬底上电沉积Ni薄膜的表面生长。在生长初期，在(100)Ni衬底上成核的岛沿相同的晶体取向横向生长，横截面看起来是长方形的。生长表面表现出由线性表面扩散普适类表征的正常标度行为。随着时间的推移，生长发生了不稳定性，观察到了从二维生长到三维生长的转变。在这个阶段，表面生长服从反常标度，其特征是局部粗糙度指数ζ_&lt；loc&gt；=1.0，整体标度指数ζ=2.1，动力指数z=1.0。

(1) Three-dimensional growth in electrodepositionWe have made investigation into scaling properties of nickel surfaces grown by pulse-current electrodeposition using atomic force microscopy. The surface growth exhibits an anomalous dynamic scaling behavior characterized by a local roughness exponent ζ_<loc>, global scaling exponent ζ and dynamic exponent z for an intermediate time regime I^z < L^z where I and L denote a window length and system size. The local interface width of the nickel surfaces leads to ζ_<loc>=1.0, global scaling exponent ζ=2.8 and dynamic exponent z=4.1. All the experimental data collapse on a plot of the anomalous scaling function.(2) Two-dimensional growth in electrodepositionSurface growth of Ni thin films electrodeposited on (100) Ni substrates has been investigated using atomic force microscopy. In the early stage of growth, islands nucleated on the (100) Ni substrates, which appear to be rectangular in cross section, grow laterally in the same crystallographic orientation. Growth surfaces are shown to display a normal scaling behavior characterized by the linear surface diffusion universality class. Along the time evolution, instability in growth occurs and a transition from two-dimensional growth to three-dimensional growth is observed. In this stage, surface growth obeys anomalous scaling characterized by a local roughness exponent ζ_<loc>=1.0, global scaling exponent ζ=2.1 and dynamic exponent z=1.0.