EMISSION CHARACTERISTICS OF SILICON VACUUM TRIODES WITH 4 DIFFERENT GATE GEOMETRIES

Arrays of 10 x 10, 30 x 30, and 50 x 50 phosphorus-doped, 0.005-0.025 OMEGA . cm, monocrystalline silicon field emitters have been fabricate d with an emitter height of approximately 4.5 mum, a cone angle of 110 -degrees, and four gate openings ranging from 1.8 to 5.3 mum. The rims of the gates are placed from coplanar with the apeces of the emitters for the 1.8-mum devices, to fully recessed for the 5.3-mum devices. T he devices have been characterized in terms of geometry-dependent beta factors, scaling of emission currents with array size, temperature de pendency from room temperature to 48 K, pressure dependency from 2.5 x 10(-9) to 0.8 x 10(-5) torr, current fluctuations at room temperature and at 48 K, and image formation. All of the measurements have been p erformed by operating the devices in the gate-induced field emission m ode.