Field Emission Ion Source Using a Carbon Nanotube Array for Micro Time-of-Flight Mass Spectrometer

Abstract

In this paper, we present the fabrication and test of a carbon-nanotube (CNT)-based field emission ion source for a micro time-of-flight mass spectrometer (µ-TOF MS). The µ-TOF MS is composed of two parts, i.e., a field emission ion source and a mass analyzer. Molecules are ionized by the impact of electrons emitted from CNTs. We calculated the ion beam path using a commercial electrodynamics simulation tool (Simion ver. 7). The results of the ion beam path simulation show that the ions generated in the effective ionization region can pass only between the first acceleration electrode pair. We fabricated a CNT-based field emission ion source for the µ-TOF MS. The electron current of the field emitter and the ion current of the ion source were measured. Through the characteristic test of a field emission ion source, we confirmed that the fabricated ion source is feasible for the µ-TOF MS.