Ionic photofragmentation of SiH4 has been studied in the vicinity of the Si: L-edge using synchrotron radiation and time-of-flight mass spectrometry. Relative ionization efficiencies for more then 10 ionic fragment species and pair-ionization efficiencies for the pairs H+ + SiHn+ (n=0, 1 and 2) have been obtained as a function of the photon energy from 100 to 200 eV from the photoelectron-photion and the photoion-photoion coincidence measurements. Ionic dissociation of the continuum Si: 2p hole states may occur mostly via double ionization of the parent molecule giving rise to two types of dissociation channels; (type A) SiH4++ → H+ + H+ + neutrals and (type B) SiH4++ → H+ + Si+ (or SiH+) + neutrals. The average kinetic-energy release given to H+ is much higher in the dissociation channel B than in the dissociation channel A suggesting temporal existence of localized and delocalized valence-two-hole states.
ASJC Scopus subject areas
- Atomic and Molecular Physics, and Optics
- Mathematical Physics
- Condensed Matter Physics