Photosensitive field emission from silicon point arrays

Abstract

Efficient photoemission has been demonstrated from uniform large‐area arrays of field emitters, fabricated at densities of 10⁶ in.⁻² by microetching techniques in p‐type silicon. Such arrays were shown to emit electrons into vacuum when biased by a closely spaced plane anode (125‐ to 500‐μm spacing) at a few kilovolts. No high‐vacuum cesiation or high‐temperature cleaning is required to observe this emission. Stable reflective photosensitivities exceeding 1500 μA/lm and quantum efficiencies of 2% at 1.06 μm and 28% at 0.90 μm have been demonstrated in thick p‐type silicon arrays.