Open AccessIncreased process latitude in absorbance-modulated lithography via a plasmonic reflector
Author(s) -
Charles W. Holzwarth,
John E. Foulkes,
Richard J. Blaikie
Publication year - 2011
Publication title -
optics express
Language(s) - Uncategorized
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.19.017790
Subject(s) - optics , materials science , lithography , plasmon , wavelength , opacity , optoelectronics , reflector (photography) , photoresist , layer (electronics) , physics , nanotechnology , light source
Absorbance-modulated lithography is a relatively new optical patterning method where a thin layer of photochromic molecules is placed between the far-field optics and photoresist. These molecules can be made transparent or opaque by illuminating with wavelengths λ1 or λ2, respectively. By simultaneously illuminating this layer with patterns of both wavelengths it is possible to create an absorption mask capable of subwavelength resolution. This resolution comes at the price of limited contrast and depth-of-focus resulting in poor process latitude. Here it is shown that by using TM polarization for λ1 and integrating a plasmonic reflector process latitude is increased by up to 66%.