Page 214 - Academic Press Encyclopedia of Physical Science and Technology 3rd Polymer

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Encyclopedia of Physical Science and Technology en012K-946 July 26, 2001 11:14

Polymers, Photoresponsive

(in Electronic Applications)

Elsa Reichmanis
Omkaram Nalamasu
Francis Houlihan

Bell Laboratories, Lucent Technologies

I. Introduction
II. Polymer Materials Requirements
III. Historical Perspective
IV. Chemically Amplified Resists
V. Polymers for Sub-150-nm Imaging Applications
VI. 157-nm Resist Design
VII. Conclusion

GLOSSARY Developer A solvent- or aqueous-based liquid medium
that will selectively remove either the irradiated por-
Chemically amplified resists Resists where the initial tions of a resist film in the case of positive resists or
exposure to either light or radiation generates a catalyst unexposed areas in the case of negative acting resists.
which then acts on the surrounding material to initiate Dissolution-inhibition resists Resists that are composed
a series of reactions that lead to solubility changes in of an inherently aqueous-base-soluble matrix resin and
the matrix. a second component that is insoluble in aqueous media
Contrast The maximum rate change of normalized re- that renders the matrix insoluble in aqueous solution
sist thickness per input energy (on a logarithmic scale) as well. Irradiation effects a structural change in dis-
achieved upon development of a resist. solution inhibitor such that dissolution rate of exposed
Conventional photoresist A photoresist materials that is areas is more than that of the matrix resin, thus causing
largely comprised of a substituted novolac resin and a a dissolution promotion.
diazonaphthoquinone dissolution inhibitor. Such mate- Etching resistance A measure of how effectively a resist
rials represent the largest fraction of photoresists used will withstand the etchants used to transfer images that
in the production of semiconductor devices today. have been defined in the resist into the device substrate.

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