Conjugate wave-front generation by degenerate four-wave mixing has been employed to project images with submicrometer features onto photoresist-coated substrates. The developed patterns demonstrate a resolution of >800 line pairs per millimeter for 413-nm illumination, consistent with theoretical expectations. The patterns are not degraded by speckle or edge enhancement, and the magnification is within 0.1% of unity. Focusing is accomplished by a novel interferometric procedure.
© 1981 Optical Society of America
M. D. Levenson, K. M. Johnson, V. C. Hanchett, and K. Chiang, "Projection photolithography by wave-front conjugation," J. Opt. Soc. Am. 71, 737-743 (1981)