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Publication Citation: Contour Metrology using Critical Dimension Atomic Force Microscopy

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Author(s): Ndubuisi G. Orji; Ronald G. Dixson; Andras Vladar; Bin Ming; Michael T. Postek;
Title: Contour Metrology using Critical Dimension Atomic Force Microscopy
Published: April 09, 2012
Abstract: The critical dimension atomic force microscope (CD-AFM), which is used as a reference instrument in lithography metrology, has been proposed as a supplemental instrument for contour measurement and verification. However, although data from CD-AFM is inherently three dimensional, the planar two-dimensional data required for contour metrology is not easily compared with the top-down CD-AFM data. This is largely due to the limitations of the CD-AFM scanning strategy. We describe scanning techniques and profile extraction methods to obtain contours from CD-AFMs, and some of the limitations. Potential sources for error for this approach are described, and a rigorous uncertainty model is presented. Our objective is to show which data acquisition and analysis methods could yield optimum contour information while preserving some of the strengths of CD AFM metrology. We present comparison of contours extracted using our technique to those obtained from the scanning electron microscope (SEM), and the helium ion microscope.
Proceedings: Proc. SPIE Metrology, Inspection, and Process Control for Microlithography XXVI
Location: San Jose, CA
Dates: February 12-17, 2012
Keywords: contour metrology; critical dimension atomic force microscope; scanning electron microscope; helium ion microscope
Research Areas: Instrumentation, Nanomanufacturing, Atomic force microscopy (AFM), Characterization, Nanometrology, and Nanoscale Measurements
PDF version: PDF Document Click here to retrieve PDF version of paper (1MB)