Enhanced sputter and secondary ion yields using MeV gold nanoparticle beams delivered by the Andromede facility
Résumé
Andromede is a new instrument for mass spectrometry analysis of nanodomains and nano-objects present on a surface. The molecular sample information (mass and structure) is obtained from time-of-flight spectra of secondary ions emitted under the impact of nanoparticles (NPs), as A u n q + with n/q up to 200 accelerated by a 4 MV single stage electrostatic Pelletron® accelerator. Such projectiles, providing huge emission rates per impact, permit the topographic analysis of complex samples. The energy deposition of these massive gold NPs induces surprisingly large holes of about 100 nm diameter in very thin graphene foils and average sputtered volume per impact of about 106 nm3 in a thick polymer material. The use of such massive clusters associated with multianode detectors, allowing the simultaneous detection of several ions of a given mass, permits correlation studies between the emitted ions within a single impact, shedding additional light on the chemical composition and structure of the analysed sample as illustrated here for various samples from metallic surfaces to biologic molecules deposits.
Origine : Fichiers éditeurs autorisés sur une archive ouverte