Development of new plasma instruments is needed to enable constellation-
and small satellite-based missions. Key steps in the development pathway
of ultra-compact plasma instruments employing lithographically patterned
wafers are the implementation of layer-to-layer electrical interconnects
and demonstration of massively parallel measurements, i.e., simultaneous
measurements through multiple identical plasma analyzer structures. Here
we present energy resolved measurements of electron beams using a
5-layer stack of wafer-based, energy-per-charge, electrostatic
analyzers. Each layer has eight distinct analyzer groups that are
comprised of multiple micron scale energy-per-charge analyzers. The
process of fabricating the electrical interconnects between the layers
is described and the measured energy resolution and the angular
resolution compared to theoretical predictions. The measurements
demonstrate successful operation of 400 micron scale analyzers operating
in parallel.