Micromechanical shutter based mass spectrometers

New shutter systems based on MEMS technology (Micro‐Electro‐Mechanical System) allow to build new types of ultra‐low weight mass spectrometers for applications in space. Applications include compact particle velocity filters and the replacement of the conventional carbon foil or secondary electrons emitting start surface used in time‐of‐flight mass spectrometers. The PRIMA instrument (PRIsma Mass Analyzer), a MEMS shutter based time‐of‐flight mass spectrometer based on the Solar WInd Monitor (SWIM) sensor developed for the Indian Chandrayaan‐1 mission, will be used for flight‐verification of the MEMS shutter technique. We review the expected performance of this instrument. The PRIMA instrument will be launched on the Swedish Space Corporation’s PRISMA satellite in 2008/2009.