Determination of acid diffusion and energy deposition parameters by point e-beam exposure in chemically amplified resists

A new method for the measurement of acid diffusion in chemically amplified resists is introduced. It is based on the measurement of the diameter of lithographic features (pillars for negative resists) obtained from single pixel e-beam exposures to determine the proximity function in a wide range of doses and PEB times. The method is applied in the measurement of the diffusion coefficients of two negative chemically amplified resists, the commercial resist SAL-601 (Shipley) and a prototype epoxy novolac based resist (EPR) developed at IMEL. The method directly provides proximity effect correction parameters for chemically amplified resists.