Dissociative electron attachment to Pt(PF3)4a precursor for Focused Electron Beam Induced Processing (FEBIP)

Experimental absolute cross sections for dissociative electron attachment (DEA) to Pt(PF 3 ) 4 are presented. Fragment anions resulting from the loss of one, two, three and four PF 3 ligands as well as the Pt(PF 3 )F and the F ions were observed. The parent anion Pt(PF 3 ) 4 is too short-lived to be detected. The dominant process is loss of one ligand, with a very large cross section of 20000 pm 2 ; the other processes are about 200 weaker, with cross sections around 100 pm 2 , the naked Pt anion is formed with a cross section of only 1.8 pm 2 . The resonances responsible for the DEA bands were assigned based on comparison with electron energy-loss spectra and spectra of vibrational excitation by electron impact. Bands around 0.5 eV and 2 eV were assigned to shape resonances with single occupation of virtual orbitals. A DEA band at 5.9 eV was assigned to a core-excited resonance corresponding to an electron very weakly bound to the lowest excited state. An F band at 12.1 eV is assigned to a core excited resonance with a vacancy in an orbital corresponding to the 2nd ionization energy of the PF 3 ligand. Implications of these findings for FEBIP are discussed. Pt(PF 3 ) 4 , used as a precursor for electron-beam nanofabrication, is easily decomposed by slow electrons.