Field emission magnetic sensors based on focusing devices

In the present article we analyze a vacuum microelectronics magnetic sensor based in a simple configuration with a double-gated wedge emitter with a s plit anode as current detector. The actuation of such device has been simul ated using several numerical approaches including full determination of ele ctrostatic potentials with accurate description of fields at the wedge regi on, electron beam propagation inside the device, and evaluation of the curr ent density distributions at the anode detector screen. Calculated sensor s ensitivities are larger than those found in conventional magnetic field sen sors designed to detect similar magnetic field ranges. The focusing system provides a tuning mechanism able to change the sensor sensitivity and the m agnetic field detection working range. The dependence of the sensitivity on geometrical parameters and control voltages is discussed. (C) 2001 Elsevie r Science Ltd. All rights reserved.