Curved Microchannel Plates for Spaceflight Mass Spectrometers

This proposal will develop long, continuous, curved microchannel plates (MCPs) for use in spaceflight ion mass spectrometers. These instruments obtain ion mass in part by measuring the ion speed. Ions create secondary elections, first as they enter the instrument window, then as they ht a target. The flight time across the distance in between provides the speed. The time is measured by detecting secondary electrons from the window and then the target. Curved MCPs simplify the detection because: they have a cylindrical symmetry which is compatible with instrument fields of view; the MCP channels always have the same orientation to electron flight paths, and so create uniform azimuthal detection efficiency; and they may be placed close to the window and target, thereby improving time of flight and mass resolution. Curved MCPs will be developed starting with the successful Incom approach for flat MCPs. A glass capillary array is first formed with 20 micron pores. Using Atomic Layer Deposition, the array is then coated with thin films that create the desired resistance and gain.