Spectroscopic characterization of acid generation and concentration and free volume evolution in chemically amplified resists

Measurement of proton concentration and local viscosity in a polymeric chemically amplified photoresist material was reported. These properties were interrogated using crystal violet, a cationic triphenylmethane dye molecule. The presence of two singlet electronic states in crystal violet explained the two-component population relaxation behavior of this family of molecules. Results suggested that the polymer matrix was sufficiently fluid to limit the long term stability of lithographic patterns writing process in this material.