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Critical Dimension Calibration Standards for ULSI Metrology



Richard A. Allen, Michael W. Cresswell, Christine E. Murabito, Ronald G. Dixson, E. Hal Bogardus


NIST and International SEMATECH are developing single-crystal reference materials for use in evaluating and calibrating critical dimension (CD), that is linewidth, metrology tools. Primary calibration of these reference materials uses a high-resolution transmission electron microscopy (HRTEM) image of the cross-section of the feature at sufficient magnification to resolve and count the individual lattice planes. Transfer calibration based on electrical test structure metrology techniques has been evaluated and reported previously. This paper reports preliminary findings on the use of AFM metrology for transfer calibration. Recent work has centered on evaluating the performance of these CD reference materials in the metrology tools which we expect will comprise the bulk of their usage: the critical dimension scanning electron microscope (CD-SEM) and atomic force microscope (AFM). The type of atomic force microscope under considerations, the critical dimension AFM (CD-AFM), uses flared tips and two-dimensional feedback to allow scanning of near-vertical sidewalls. It is currently expected that the CD-AFM will serve a key role in the transfer calibration. Additionally, since earlier samples showed a high variability in the appearance of the samples, screening using the CD-SEM and CD-AFM will provide verification that each device meets minimal visual characteristics.
Proceedings Title
Characterization and Metrology for ULSI Technology: 2003
Conference Dates
March 24-28, 2003
Conference Location
Austin, TX, USA
Conference Title
International Conference on Characterization and Metrology for ULSI Technology


AFM, SEM, CD Reference materials, linewidth metrology


Allen, R. , Cresswell, M. , Murabito, C. , Dixson, R. and Bogardus, E. (2003), Critical Dimension Calibration Standards for ULSI Metrology, Characterization and Metrology for ULSI Technology: 2003, Austin, TX, USA, [online], (Accessed June 21, 2024)


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Created September 29, 2003, Updated October 12, 2021