| 摘要 |
A process for quantifying the results of a planarization process provides metrics that can be applied to process parameters that affect the planarization results at various localized regions on a surface being planarized. A surface of a work piece is planarized and the results are recorded as an experimental work piece scan by a plurality of measurements of the amount of material removed as a function of the location on the surface of the work piece. The data from the plurality of measurements are fitted to an mth order polynomial to construct an approximation of a low spatial frequency scan. The work piece surface is then divided into a plurality of regions, each of the regions influenced by a process variable in the planarization process. The approximation of the low spatial frequency scan is then analyzed in each of the regions by fitting the low spatial frequency scan in that region to an nth order polynomial. The coefficient of the nth order term is used as a metric for the results in that region. Subsequent work pieces can be processed and measured in like manner; and if a process parameter is changed, changes in the resulting metrics can be used to quantify the results of using the changed process parameter. In a further embodiment, an approximation of a high spatial frequency scan can be achieved by subtracting the approximation of the low spatial frequency scan from the experimental work piece scan. A metric, such as standard deviation, can be used to quantify results of changes in parameters affecting the high spatial frequency components of the process.
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