CMP加工后芯片三维形貌表征参数体系

Parameter System for Characterization of 3D Morphology of Chip after CMP Processing

针对当前化学机械抛光(chemical mechanical polishing,CMP)后的芯片表面形貌的表征常常只停留在研究二维轮廓特征,无法完整地表达整个三维表面形貌信息,仅使用单一的评定指标来表征其表面的不平整程度等问题,建立了1个科学、全面的芯片表面形貌评定参数体系应用于工程表面粗糙度评定中,通过分析芯片表面形貌的幅值分布特征,结合芯片表面的统计特性,基于ISO 25178-2标准表征参数建立适用于芯片表面三维评定的表征参数体系.仿真结果表明:CMP加工后芯片表面形貌的幅值近似服从高斯分布;分形维数D可以准确表征芯片表面形貌,反映其复杂程度;通过幅度参数、空间参数、混合参数和分形参数建立的芯片表面形貌评定体系能够从多方面表征芯片三维表面形貌特征,对芯片表面形貌参数评定具有一定的可行性.

Deficiencies of the current characterization of the surface morphology of the chip after chemical mechanical polishing,i.e.the two-dimensional contour features without the whole three-dimensional surface morphology information,and the usage of a single evaluation index to characterize the surface roughness and other issues,a scientific and comprehensive chip surface morphology evaluation parameter system was established and applied to the engineering surface roughness evaluation.By analyzing the amplitude distribution characteristics of chip surface morphology combined with the statistical characteristics of chip surface,a characterization parameter system suitable for chip surface3D evaluation was established based on ISO 25178-2 standard characterization parameters.The simulation results showed that the amplitude of chip surface topography after CMP processing approximately obeyed Gaussian distribution.Fractal dimension D accurately characterized the surface morphology of the chip and reflected its complexity.The chip surface topography evaluation system established by amplitude parameters,space parameters,mixing parameters and fractal parameters can characterize the three-dimensional surface topography characteristics of the chip from many aspects,and had certain feasibility for the evaluation of chip surface topography parameters.