Tip positioning, Interferometric-Spatial-Phase Imaging, ISPI, Scanning-probe lithography
Drift and perturbations in tip positioning
This invention provides a method for direct, nanometer-precision referencing of a scanning probe tip to a substrate, using Interferometric-Spatial-Phase Imaging (ISPI), which was applied previously to template alignment and gap control. In the present invention, a probe tip is attached to a transparent, planar support structure, or a reference flat, which contains grating patterns. During lithography, the substrate is scanned underneath the tip in X and Y directions, and the position of the reference flat and hence the tip position is referenced to the substrate position using ISPI marks, allowing continuous correction for thermal drift and other errors.
Ability to write arbitrary patterns with high precision and repeatability over large areas in a mass-production process
Dr. Euclid E. Moon (Research Laboratory of Electronics, MIT)
E.E. Moon, J. Kupec, M.K. Mondol, H.I. Smith, and K.K. Berggren, “Atomic-force lithography with interferometric tip-to-substrate position metrology”, J. Vac. Sci. Technol. B, 25, 2284 (2007). An illustrative figure.
Last revised: April 29, 2013
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