ABSTRACT
Theconceptof“chemicalampliŸcation”(ItoandWillson,1983;Ito,2005)hasmadeagreat impactonresistdesigns.ChemicallyampliŸedresistsutilizeacid-catalyticreactionstoformlatent imagesbeforedevelopment.Acidsproducedbyexposurediffuseintheresistmatrixandcatalyze chemicalreactions,suchasdeprotection.Intheearlystageofthedevelopmentoftheseresists,there occurred many problems associated with the acid-catalytic reaction coupled with acid diffusion. Theinstabilityofresistperformanceandtheformationofsurfaceinsolublelayersareamongthese. Owingtotheirworldwideintensivedevelopment,theperformanceofchemicallyampliŸedresists hadbeenimprovedforpracticaluse.ChemicallyampliŸedresistswereŸrstdeployedinthemass productionlinesofsemiconductordevicesduringthetransitionoftheexposuretoolfromtheiline of a Hg lamp to a KrF excimer laser. Since then, chemically ampliŸed resists have been used as a mainstreamresisttechnologyinKrF,ArF,andArFimmersionlithography.Despiteaciddiffusion, sub-60-nm features have been resolved in the mass production lines of semiconductor devices.
