Sub-quarter micron contact hole fabrication using annular illumination

Miklós Erdélyi, Zsolt Bor, Gábor Szabó, Joseph R. Cavallaro, Michael C. Smayling, Frank K. Tittel, William L. Wilson

Research output: Contribution to journalConference article


Details of an experimental demonstration of a contact hole imaging system are reported in which the depth of focus is increased by a factor of about 3.5 using annular illumination. Due to spatial filtering and nonlinearity of the photoresist, the resolving power was enhanced by 52% and it was possible to pattern a 0,28 μm contact hole in photoresist deposited on a silica substrate. This technique is capable of fabricating sub-quarter micron holes using excimer laser radiation at 193 nm.

Original languageEnglish
Pages (from-to)88-93
Number of pages6
JournalProceedings of SPIE - The International Society for Optical Engineering
Publication statusPublished - Dec 1 1996
EventOptical Microlithography IX - Santa Clara, CA, United States
Duration: Mar 13 1996Mar 15 1996



  • Annular aperture
  • Depth of focus
  • Microlithography

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Condensed Matter Physics
  • Computer Science Applications
  • Applied Mathematics
  • Electrical and Electronic Engineering

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