Fabrication of PMMA clad polyimide waveguides by electron beam lithography creates very smooth sidewalls allowing production of narrow low loss waveguides on planar substrates.
© 1990 Optical Society of America
M. J. Rooks, H. V. Roussell, and L. M. Johnson, "Polyimide optical waveguides fabricated with electron beam lithography," Appl. Opt. 29, 3880-3882 (1990)