Real‐time localization of single C 60 impacts with correlated secondary ion detection

We assembled hardware and software for the synchronized detection of electrons and ions emitted under the impacts of the individual C 60 + and C 60 2+ ions. A projectile impact is localized via the ejected electron(s) with an emission electron microscope (EEM). The ( x , y ) coordinates of each impact combined with the corresponding record of detected secondary ions (Sis), allow the construction of mass‐selected surface maps. The setup comprises a custom‐built ToF‐SIMS with a C 60 1, 2+ source, an EEM with an electron imaging detector consisting of dual microchannel plates (MCPs), phosphor screen and a 1.3 megapixel CMOS camera. The electron pulse on the aluminized phosphor screen triggers the camera resulting in a frame with the electron image. It also triggers the ToF electronics resulting in a suite of SI time records corresponding to each individual impact event. The data processing and management are handled by custom software including combination of the positional and the mass spectrometric information from each impact. The present study demonstrates the feasibility of mapping a surface by localizing the SI emission from single C 60 2+ impacts. A spatial resolution of 1.3 µm has been obtained. Interestingly, maps of coemitted SIs from a given localization display chemically resolved information from an emission area of ∼10 2 nm 2 . Copyright © 2010 John Wiley & Sons, Ltd.