Resist design, photoinitiators

In all three of these designs, chemical amplification is the result of photoinitiated chain or catalytic reactions where irradiation is used only to initiate a chain reaction or to generate a catalyst within localised areas of a resist film. 

Applications of Photoinitiators to the Design of Resists for Semiconductor Manufacturing... 

Over the years, a number of compounds have been identified to photoinitiate cationic polymerization of monomers designed for radiation curing applications generally, and negative-resist applications specifically. The most prominent of these initiators are onium salts. 

Ito and C.G. Willson, Chemical amplification in the design of dry developing resist materials, Polym. Eng. Sci. 23, 1012 (1983) H. Ito, C.G. Willson, and J.M.J. Frechet, Positive and negative working resist compositions with acid generating photoinitiator and pol3mier with acid labile groups pendant from polymer backbone, U.S. Patent No. 4,491,628 (1985). 

Ito, H. and Willson, C.G., Applications of photoinitiators to the design of resists for semiconductor manufacturing, in Polymers in Electronics, Davidson, T, Ed., American Chemical Society, Washington, D.C., 1984, 11. 

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