The study of novel photoresists is of paramount importance in several application-oriented fields, ranging from microelectronics to photonics, nanofabrications, sensors development. In whatever domain the realisation of micro/nanostructures on photoresist is required, a high spatial resolution combined with a high sensitivity is strongly pursued, together with the possibility of adding new photoresist features.

Since several years we have been involved in the study of possible photoinitiators. It was demonstrated that the irradiation of suitable aryl halides, sulfonates or phosphates (ArX) caused an efficient release (ca. 100%) of the corresponding strong acids (HX) such as HCl, sulfonic and phosphoric acids by heterolysis of the Ar-X bond. It is thus possible to tune the strength of the photogenerated acid by modifying the group X.

References

1. Terpolilli, M.; Merli, D.; Protti, S.; Dichiarante, V.; Fagnoni, M.; Albini, A. “Cationic and Radical Intermediates in the Acid Photorelease from Aryl Sulfonates and Phosphates” Photoch. Photobio. Sci. 2011, 10, 123-127. DOI: 10.1039/C0PP00284D