Method and apparatus for trapping ions by increasing trapping voltage during ion introduction

Abstract

A method and apparatus for trapping ions in an ion trap having a ring electrode and a plurality of end-cap electrodes. Ions are introduced into a ion trap cavity of the ion trap from an external source or by desorption of a substance in the ion trap cavity. In a first embodiment, as the ions are introduced in the ion trap cavity, the amplitude of an RF voltage being applied to the ring electrode is gradually increased to trap the ions in the ion trap cavity. In a second embodiment, as the ions are introduced in the ion trap cavity, a retarding voltage is applied to the end-caps to reduce the initial kinetic energy of the ions. In a third embodiment, as the ions are introduced in the ion trap cavity from a probe tip inserted in the cavity, a retarding voltage is applied to the probe tip.

Dependencies are inferred from the claim text.