This paper discusses research on an automatic focusing system for IC-linewidth measuring instruments. The instrument incorporates a collimated light source, a device to move a sample in small, precise increments, and a charge-coupled device. The autofocusing model would measure the step-height of a dielectric sample and correlate the height to a focus position. Thickness of samples on an enlarged scale were measured to verify the feasibility of this device.
Library of Congress Subject Headings
Optical measurements--Instruments--Design; Integrated circuits--Masks--Measurement--Instruments; Semiconductor wafers--Measurement--Instruments
Department, Program, or Center
School of Photographic Arts and Sciences (CIAS)
Ingraham, John, "Model automatic focusing system for linewidth measuring instruments" (1985). Thesis. Rochester Institute of Technology. Accessed from
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