MOLECULAR DESIGN OF DISSOLUTION INHIBITOR IN CHEMICAL AMPLIFICATION RESIST SYSTEM BY MOLECULAR-ORBITAL METHOD - TRANSPARENCY AND REACTIVITIES WITH PROTONS

The molecular orbital(MO) method has been applied to study the transpa rency of any dissolution inhibitors in the deep-UV region and the reac tivities of those molecules with protons derived from a photoacid gene rator in a chemical amplification resist system for excimer laser lith ography. The results indicate that 1,3-bis(tert-butoxycarbonyloxy) ben zene is the best dissolution inhibitor with respect to both the transp arency and the reactivities among the five dissolution inhibitors stud ied, because it has small absorption peaks in the wavelength range lon ger than 215 nm and easily decomposes into the oxycarbonyloxyl compoun d and the tert-butyl group upon proton attack, The validity of the MO approach is confirmed by the experimental results.