薄膜表面的分形特征

Fractal Characteristics of Film Surface

在计算机上用随机数相加的方法产生了一个分形表面，对这个表面的模拟测量表明，z方向分辨率变化对分形维数测量结果影响很小，x、y方向分辨率降低时会导致测量结果统计误差增大用扫描隧道显微镜（STM）测量了沉积在三种不同基底上的Au膜的分形维数．测得Au／陶瓷的分形维数D＝2.15，Au／光学玻璃的分形维数D＝2.06．Au／载玻片上各点的分形维数较不一致．同时讨论了多图方法中各单图曲线之间不衔接的原因．

A fractal surface was generated on computer by random addition method. The simulated measurement on this surface shows that z resolution has little effect on calculating fractal dimension D while the lower x y resolution causes larger statistic error. D was calculated for Au films on three kind of substfate using data from Scanning Tunneling Microscope(STM) images. D = 2. 15 for Au/ceramic, and D = 2. 06 for Au/optical glass. D has different values for different points on Au/general glass, the reason of mismatch between curves from STM images of different scan sizes was also discussed.