Metrological atomic force microscope and traceable measurement of nano-dimension structures

Sitian Gao, Mingzhen Lu, Wei Li, Yushu Shi, Qi Li


The quantity assurance in semiconductor industry development requires dimensional measurement with nanometer accuracy. A metrological AFM is designed to establish a traceable standard with nanometer uncertainty. The principle and design of the instrument is introduced in this paper. The displacement of the sample is traced to the SI unit by interferometers. The metrological AFM is applied to step height and line width measurement. The results are compared with optical instrument and profilometer. The metrological AFM is used to step height measurement in an international comparison and the result shows an uncertainty less than 2 nm. The application of metrological AFM in line width and pitch are also introduced.

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