Dissociative electron attachment to triflates*

It is known that understanding of chemical transformations induced by low energy electrons reacting with photoresist components is crucial for effective design of chemically amplified resists in modern lithography. Therefore in present work gas phase studies on dissociative electron attachment to simple alkyl (CF$_{3}$SO$_{3}$CH$_{3})$ and aryl (C$_{6}$H$_{5}$SO$_{3}$CF$_{3}$ and CF$_{3}$SO$_{3}$C$_{6}$H$_{4}$CH$_{3})$ triflates were carried out. The fragmentation pathways under electron impact below 10 eV were identified by means of crossed electron-molecular beam mass spectrometry. Several reaction channels were observed upon an electron capture by the studied compounds, involving single or multiple bond cleavages or intramolecular rearrangement. Three main dissociation channels were observed that are C-O, S-O or C-S bond breakage in the triflate moiety leading to the formation of triflate (OTf), triflyl (Tf) or sulfonate (RSO$_{3})$ anions, respectively. The results of this work can be helpful at later stage in the improvement of the image quality in post optical lithography processes.