The oxidized porous silicon field emission array

The goal of developing a highly efficient microwave power source has led us to investigate new methods of electron field emission. One method presently under consideration involves the use of oxidized porous silicon thin films. We have used this technology to fabricate the first working field emission arrays from this substance. This approach reduces the diameter of an individual emitter to the nanometer scale. Tests of the first samples are encouraging, with extracted electron currents to nearly 1 mA resulting from less than 20 V of pulsed DC gate voltage. Modulated emission at 5 MHz was also observed. Development of a full-scale emission array capable of delivering an electron beam at 18 GHz of minimum density 100 A/cm/sup 2/ is in progress.<
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