纳米Al薄膜表面形貌与导电性的分形表征

Nano-Al Film Surface and Electrical Resistivity Characterized by Fractal

磁控溅射法在Si(111)基底上制备了纳米Al薄膜,用高度相关函数法对薄膜的原子力显微镜图像进行分形维计算,并用四点探针法测量了薄膜电阻.结果表明,随着溅射时间的延长,薄膜表面质量提高,分形维增大,电阻率也随着分形维的增大而增大;随着退火温度的上升,薄膜表面质量下降,分形维和电阻率也随之降低.因此认为,分形维能够较好的表征薄膜表面形貌,分形维与薄膜电阻率存在对应关系,并指出用分形维可以优化溅射工艺参数.

Al thin films were deposited on Si（111） wafers by magnetron sputtering. In order to acquire fractal dimension（FD） of surface, height-height correlation function was applied to analyze the atomic force microscopy images. The Electrical conductivity of the film was examined with four-probe measurement. The results indicate that the surface quality, FD and resistivity of the film increase with the sputtering time, but decrease with the Annealing temperature. It is concluded that the FD may be applied to describe the morphologies and resistivity of the film perfectly and optimize the sputtering parameters of sputtering procedure.