An integrated field emission electron source on a chip fabricated by laser-micromachining and mems technology

A silicon field emission electron source consisting of a cathode and a grid electrode has been fabricated by laser micromachining. The cathode features 21x21 tips on an area of 4x4 mm(2). With a self-aligning MEMS technology for the aperture grid, a high electron transmission (99 %) was achieved. Onset voltages of 50...70 V were observed for an emission current of 1 nA. A stable emission current of 1 mA +/- 1.3 % at an extraction voltage of 250 V was observed during a 30-min operation.