| Abstract
| - A technique to determine the efficiency of the decomposition of photoacid generators toproduce photoacid and the concentration of acid necessary to image chemically amplifiedphotoresists was designed, implemented, and validated. The technique is analogous to astandard addition experiment; known concentrations of a base quencher are added to a seriesof otherwise identical resist formulations. To produce the same free acid concentration withinthe resist films after neutralization, the concentration of photogenerated acid must increaseby an amount equal to the known concentration of added base. The increase in exposuredose required to create this additional acid is indirectly determined as a function of baseloading using resist dissolution behavior (contrast curves). The main assumptions implicitin the model to extract the Dill C parameter (a parameter proportional to the quantumyield) from experiments were validated using X-ray exposure and a positive tone photoresistsystem consisting of poly(p-t-butoxycarbonyloxystyrene-co-p-hydroxystyrene) as the baseresin, norbornene dicarboximidyl triflate as the photoacid generator, and 1-piperidineethanolas the base quencher. Resin deprotection monitored by FTIR and dissolution rate measurements provided independent evidence that the bulk dissolution rate, the dissolution inductiontime, and the extent of deprotection as a function of the free acid concentration remainedthe same for resists with and without base.
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