Silicon rice-straw array emitters and their superior electron field emission

Free standing and vertically aligned silicon rice-straw- like array emitters were fabricated by modified electroless metal deposition (EMD), using HF-H₂O₂ as an etching solution to reduce the emitter density and to make the emitter end of the formed silicon rice-straw arrays shaper than those formed by conventional EMD. These silicon rice-straw array emitters can be turned on at E₀ = 4.7 V/μm, yielding an EFE (electron field emission) current density of J_e = 139 μA/cm ² in an applied field of 12.8 V/μm. According to a simple simulation, the excellent EFE performance of the silicon rice-straw array emitters originates in not only the favorable distribution of emitter arrays, but also the shape of the emitter apexes. The modified-EMD method is easily scaled up without expensive equipment, so silicon rice-straw array emitters are a promising alternative to silicon-based field emitters.