MEMS ion source for ion mobility spectrometry

This paper describes a miniature, silicon-glass, electron-impact ion source, in which a field emission carbon nanotube cathode is separated from the external atmosphere by a semitransparent Si3N4 membrane. High vacuum necessary for the proper operation of the ion source is generated on a chip by an integrated micropump. The experiment revealed that it is possible to obtain and maintain high vacuum inside the structure; however, some problems associated with outgassing occurred during field emission measurements. Despite this fact, both the transmission of electrons through the thin membrane and the possibility of gas ionization have been confirmed. Published by the AVS.