Developing a Crossed-Field Test Structure with Gate Field Emission Arrays

We are developing a Crossed-Field Amplifier (CFA) experiment utilizing silicon Gate Field Emitter Arrays (GFEA) [1]. These devices have 9M emitter tips, but we are currently developing a driver system using arrays of 1000 x 1000 emitter tips [1]. The driver provides a 1 ms duration square pulse up to 60 V to drive the GFEAs in a repetitive or single shot mode. The driver circuit communicates wirelessly to a desktop computer through the “XBee” ISM 2.4 GHz module from where the pulse is triggered. In the experiment the driver system will float at -3 kV [2]. In a vacuum chamber at a pressure of 10
⁻⁸
Torr the GFEAs are tested with the driver circuit. A collector spaced 1 mm above the arrays is kept at 200 V. The driver circuit has been demonstrated for the smaller arrays, and new experiments are underway with the larger arrays which consist of 36 sub-arrays (each array of 500 x 500 emitter tips). The experimental purpose is to use the driver circuit to pulse the test structure utilizing eight 9M tip array die to generate an emission current of 150 mA capable to produce gain in the Crossed-Field Amplifier (CFA) designed at BSU [3]. Design of this experimental CFA at a frequency of 900 MHz will be discussed.