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Title: Luminescence quenching of conductive Si nanocrystals via “Linkage emission”: Hopping-like propagation of infrared-excited Auger electrons

Phosphorus (P) is an n-type dopant for conductive silicon nanocrystals (Si-nc's), the electrical activation of which may be monitored through a non-radiative Auger recombination process that quenches the Si-nc luminescence. We investigated this quenching mechanism through electrical measurements of Si-nc's. Infrared-excited Auger electron emission as the non-radiative process was directly probed and the dynamics of the process are determined from a frequency response analysis. To explain the dynamics, we propose a model in which Auger electrons with a low kinetic energy establish a local inter-nanocrystal conductance and the repetition of this local conductance results in a constant photocurrent (“linkage emission”). This emission becomes significant by electron filling in the Si-nc's owing to the electrical activation of P, which is consistent with observed luminescence quenching behavior. We found that the IR photo-excited emission is distinct from the thermally induced hopping conduction and show that confined, rather than trapped, charges are the source of the Auger electrons. Thus, the process consumes both confined charges and the recombination energy for Auger emission, which explains the luminescence quenching mechanism of Si-nc:P.
Authors:
 [1] ; ; ;  [2] ;  [3] ;  [4]
  1. National Institute for Materials Science (NIMS), Tsukuba, Ibaraki 305-0047 (Japan)
  2. Photon Science Institute and School of Electrical and Electronic Engineering, University of Manchester, Manchester M13 9PL (United Kingdom)
  3. Department of Engineering Physics and Centre for Emerging Device Technologies, McMaster University, Hamilton, Ontario L8S 4L7 (Canada)
  4. Advanced Technology Institute, University of Surrey, Guildford GU2 5XH (United Kingdom)
Publication Date:
OSTI Identifier:
22314596
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 116; Journal Issue: 6; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ELECTRON EMISSION; KINETIC ENERGY; LUMINESCENCE; NANOSTRUCTURES; PHOSPHORUS; QUENCHING; RECOMBINATION; SILICON; TRAPPING