Surfing Silicon Nanofacets for Cold Cathode Electron Emission Sites.

ACS Appl Mater Interfaces

SUNAG Laboratory, Institute of Physics, Sachivalaya Marg, Bhubaneswar 751005, India.

Published: November 2017

Point sources exhibit low threshold electron emission due to local field enhancement at the tip. In the case of silicon, however, the realization of tip emitters has been hampered by unwanted oxidation, limiting the number of emission sites and the overall current. In contrast to this, here, we report the fascinating low threshold (∼0.67 V μm) cold cathode electron emission from silicon nanofacets (Si-NFs). The ensembles of nanofacets fabricated at different time scales, under low energy ion impacts, yield tunable field emission with a Fowler-Nordheim tunneling field in the range of 0.67-4.75 V μm. The local probe surface microscopy-based tunneling current mapping in conjunction with Kelvin probe force microscopy measurements revealed that the valleys and a part of the sidewalls of the nanofacets contribute more to the field emission process. The observed lowest turn-on field is attributed to the absence of native oxide on the sidewalls of the smallest facets as well as their lowest work function. In addition, first-principle density functional theory-based simulation revealed a crystal orientation-dependent work function of Si, which corroborates well with our experimental observations. The present study demonstrates a novel way to address the origin of the cold cathode electron emission sites from Si-NFs fabricated at room temperature. In principle, the present methodology can be extended to probe the cold cathode electron emission sites from any nanostructured material.

Download full-text PDF

Source
http://dx.doi.org/10.1021/acsami.7b08738DOI Listing

Publication Analysis

Top Keywords

electron emission
20
cold cathode
16
cathode electron
16
emission sites
16
silicon nanofacets
8
emission
8
low threshold
8
field emission
8
work function
8
electron
5

Similar Publications

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!