DocumentCode :
2043436
Title :
Field Eemission Resonances from Self-Aassembled Silicon Nnanostructures
Author :
Johnson, S. ; Zülicke, U. ; Blaikie, R.J. ; Markwitz, A.
Author_Institution :
Nat. Isotope Centre, GNS Sci.
fYear :
2006
fDate :
38899
Firstpage :
299
Lastpage :
299
Abstract :
Summary form only given. Conventional Fowler-Nordheim theory of field electron emission describes the emission process as electron tunnelling from a Fermi sea through a surface potential barrier modified by an external electric field. However, a number of recent studies of field emission from nanometre-scale metallic systems reveal significant departures from this traditional description. In particular, the energy spectrum of electrons field-emitted from Au nanoclusters and W nanotips was found to consist solely of multiple peaks spread over a range of energies around the Fermi level. The existence of these peaks suggests that electrons do not tunnel directly from the bulk Fermi sea into vacuum; rather that tunnelling occurs through discrete energy levels formed in the nanotips due to spatial confinement. In this paper we report the field emission properties of self-assembled silicon nanostructures formed on an n-type silicon (100) substrate by electron beam annealing at 1000 degC for 15 s. The nanostructures are square based, with an average height of 8 nm and are distributed randomly over the entire substrate surface. Following a period of conditioning, the silicon nanostructure field emission characteristics become stable and reproducible with electron emission occurring for fields as low as 3 Vmum-1. With continued conditioning however, a number of discrete and highly repeatable current peaks develop which are superimposed on a background current well described by conventional Fowler-Nordheim theory. These current peaks are understood to result from enhanced tunnelling through resonant states formed at both the substrate-nanostructure and nanostructure-vacuum interface. Here will provide details of the experimental procedure and the corresponding experimental observations along with a theoretical model to account for the observed I-V characteristics
Keywords :
electric current; electron field emission; elemental semiconductors; interface states; nanoelectronics; nanostructured materials; resonant tunnelling; self-assembly; silicon; Fowler-Nordheim theory; Si; background current; electron field emission resonances; electron tunnelling; n-type silicon (100) substrate; nanostructure-vacuum interface; resonant states; self-assembled silicon nanostructures; square based nanostructures; substrate-nanostructure interface; superimposed current peaks; Electron emission; Elementary particle vacuum; Energy states; Gold; Nanostructures; Resonance; Sea surface; Self-assembly; Silicon; Tunneling;
fLanguage :
English
Publisher :
ieee
Conference_Titel :
Vacuum Nanoelectronics Conference, 2006 and the 2006 50th International Field Emission Symposium., IVNC/IFES 2006. Technical Digest. 19th International
Conference_Location :
Guilin
Print_ISBN :
1-4244-0401-0
Type :
conf
DOI :
10.1109/IVNC.2006.335477
Filename :
4134579
Link To Document :
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