Gated field-emission cathodes for microwave devices

The Accelerator Research Laboratory at Texas A&M University is developing gated field-emitter cathodes for microwave and millimeter-wave applications. The cathode consists of an array of gated field-emitters which are modulated at microwave frequency to produce a fully modulated electron beam. Field-emitter structures under development include gated knife-edge arrays, reentrant cusps, and porous silicon. All feature extremely high transconductance, low noise, and rugged structure as compared to earlier field-emitter structures. The field emission at the cathode surface is discussed. The knife-edge emitter geometry is described. The inverted cusp cathodes are considered. The porous silicon emitting surfaces are described.<
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