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Henry I. Smith. Tsai, Hsin-Yu Sidney Massachusetts Institute of Technology. Dept. of Electrical Engineering and Computer Science. Massachusetts Institute of Technology. Department of Electrical Engineering and Computer Science 2011-10-17T21:29:07Z 2011-10-17T21:29:07Z 2011 2011 http://hdl.handle.net/1721.1/66464 756045191 Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2011. Cataloged from PDF version of thesis. Includes bibliographical references (p. 241-251). Diffraction limits the resolution of far-field lithography and imaging to about half of the wavelength, which greatly limits the capability of optical techniques. The proposed technique with absorbance modulation aims to get around the diffraction limit by using wavelength-selective chemistry to confine light to nanoscale dimension. Absorbance modulation lithography and imaging is a near-field technique that does not require scanning of a tip in close proximity or fabrication of a physically small aperture. Near-field apertures are dynamically generated in the photochromic absorbance modulation layer (AML) with only far-field illuminations. In this thesis, the concept of absorbance modulation is explained and in-house simulation models are discussed in detail. One-dimensional experimental demonstrations of absorbance modulation lithography achieved line exposures with widths of about one tenth of the exposure wavelength. In order to extend absorbance modulation to two-dimension, a binary diffractive-optical element that generates a focused round spot at one wavelength, aligned with the central node of a ring-shaped spot at another wavelength was designed and fabricated. Lithography and imaging results applying this diffractive optical element showed evidence of point-spread function compression in lithography and contrast enhancement in imaging. by Hsin-Yu Sidney Tsai. Ph.D. 251 p. eng Massachusetts Institute of Technology M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission. http://dspace.mit.edu/handle/1721.1/7582 Electrical Engineering and Computer Science. Overcoming the far-field diffraction limit via absorbance modulation Thesis application/pdf false Publication unknown unknown <Publication xmlns="https://www.openaire.eu/cerif-profile/1.1/" id="5332d647-0787-4b52-b192-13184d143fa5"> <Type xmlns="https://www.openaire.eu/cerif-profile/vocab/COAR_Publication_Types">http://purl.org/coar/resource_type/c_1843</Type> <Language>eng</Language> <Title>Overcoming the far-field diffraction limit via absorbance modulation</Title> <PublishedIn> <Publication> </Publication> </PublishedIn> <PublicationDate>2011</PublicationDate> <Authors> <Author> <DisplayName>Tsai, Hsin-Yu Sidney</DisplayName> <Affiliation> <OrgUnit> </OrgUnit> </Affiliation> </Author> </Authors> <Editors> </Editors> <Publishers> <Publisher> <DisplayName>Massachusetts Institute of Technology</DisplayName> <OrgUnit /> </Publisher> </Publishers> <License>http://dspace.mit.edu/handle/1721.1/7582</License> <Keyword>Electrical Engineering and Computer Science.</Keyword> <Abstract>Diffraction limits the resolution of far-field lithography and imaging to about half of the wavelength, which greatly limits the capability of optical techniques. The proposed technique with absorbance modulation aims to get around the diffraction limit by using wavelength-selective chemistry to confine light to nanoscale dimension. Absorbance modulation lithography and imaging is a near-field technique that does not require scanning of a tip in close proximity or fabrication of a physically small aperture. Near-field apertures are dynamically generated in the photochromic absorbance modulation layer (AML) with only far-field illuminations. In this thesis, the concept of absorbance modulation is explained and in-house simulation models are discussed in detail. One-dimensional experimental demonstrations of absorbance modulation lithography achieved line exposures with widths of about one tenth of the exposure wavelength. In order to extend absorbance modulation to two-dimension, a binary diffractive-optical element that generates a focused round spot at one wavelength, aligned with the central node of a ring-shaped spot at another wavelength was designed and fabricated. Lithography and imaging results applying this diffractive optical element showed evidence of point-spread function compression in lithography and contrast enhancement in imaging.</Abstract> <Access xmlns="http://purl.org/coar/access_right" > </Access> </Publication>