Patent ID: 8829428

Claim:
A method for analyzing a sample, comprising: generating a continuous micro-focused beam of primary species; directing the micro-focused beam of primary species to a sample and causing secondary species to be emitted from said sample; detecting said secondary species, wherein the step of detecting said secondary species comprises applying opposed electric fields proximate to said sample surface, said opposed electric fields having an axis or plane of symmetry about said micro-focused beam of primary ions, said opposed electric fields simultaneously directing secondary species in the form of positive ions to a first detector and directing secondary species in the form of negative ions and electrons to a second detector; applying a magnetic field across the flight path of negative ions and electrons to separate the electrons from the negative ions; directing said positive ions, said negative ions or both said positive ions and said negative ions to a mass spectrometer, wherein said mass spectrometer comprises a position sensitive detector; applying at least one of a magnetic field and an electrostatic field to scan the magnetically-separated electrons across a multianode secondary electron detector along the direction of the anodes; and detecting the magnetically-separated electrons with the multianode secondary electron detector; wherein said step of detecting said magnetically-separated electrons comprises counting individual electrons; measuring a timing signal from said step of counting electrons; and using said step of counting individual electrons to establish the time of arrival of a primary ion at said sample.