MEMs Charged Particle Spectrometers for Spaceborne Applications 

Fred A.  Herrero

Detector Systems Branch Code 553/NASA GSFC

Abstract The need to miniaturize charged-particle spectrometers for NASA space
missions led to a MEMs approach that offers very large miniaturization factors
(10 to 100) without loss in in sensitivity and energy/angle resolution.
Combining a high transmission collimator channel array and a parallel plate
energy analyzer (PPA) array defines a single pixel with its own look-angle and
field-of-view; typical pixel dimensions are 3 to 5 mm thick with 0.5 to 2 cm
square base and aperture area 0.01 to 0.4 cm^2, depending on energy resolution.
Pixelated imaging plasma spectrometers can be built for ions or electrons with
energy range from a few eV to about 50 keV using 500 volt scanning supplies
(plate factors from 5 to 100 are practical).  This Flat Plasma Spectrometer
(FlaPS) geometry may be used also to obtain neutral-winds, ion-drifts, and
temperatures from the angular and energy distributions of the high ion and
neutral fluxes measured in low-Earth-orbit for ionospheric and thermospheric
investigations.  Applications, mass, power, and cost will be discussed.