Field-Induced Electron Emission from Graphitic Nano-Island Films at Silicon Substrates

Numerous carbonic nano-structured materials were reported to demonstrate electron emission in moderate electric field (1 kV/mm or less), even if their surface morphology shows no edges or tips capable of strong local field enhancement. In many such cases, the actual mechanism of emission facilitation remains unclear, partially due to the complex structure of the investigated materials usually representing a three-dimensional system of domains with different properties. In the presented work, we investigated a simpler, quasi-2d system, presumably providing better possibilities for unambiguous description of the emission mechanism. Emitters were produced by chemical deposition of small amounts of graphitic carbon at silicon substrates. The films had nano-island structure and demonstrated good emission properties with threshold electric field as low as 550 V/mm.