Picosecond photoassisted electron emission from gated p -silicon high density field emitter array

A 1 mm square array of oxidation sharpened p -type Si field emitter tips ( 2.4 μ m spacing and 1 μ m gate aperture) produces 40 ps rise time pulsed electron emission into the vacuum when excited by 110 fs duration optical pulses ( λ = 0.78 μ m ) . The observed emission quantum yield for pulsed excitation of 0.04% is partially accounted for by gate shadowing and overlap of optical absorption depth and an estimated depletion layer thickness. These results suggest that more efficient photoexcited picosecond time scale electron emission is possible from optimized semiconductor field emitter structures.