skip to main content

SciTech ConnectSciTech Connect

Title: Deactivation of metastable single-crystal silicon hyperdoped with sulfur

Silicon supersaturated with sulfur by ion implantation and pulsed laser melting exhibits broadband optical absorption of photons with energies less than silicon's band gap. However, this metastable, hyperdoped material loses its ability to absorb sub-band gap light after subsequent thermal treatment. We explore this deactivation process through optical absorption and electronic transport measurements of sulfur-hyperdoped silicon subject to anneals at a range of durations and temperatures. The deactivation process is well described by the Johnson-Mehl-Avrami-Kolmogorov framework for the diffusion-mediated transformation of a metastable supersaturated solid solution, and we find that this transformation is characterized by an apparent activation energy of E{sub A}=1.7 ± 0.1 eV. Using this activation energy, the evolution of the optical and electronic properties for all anneal duration-temperature combinations collapse onto distinct curves as a function of the extent of reaction. We provide a mechanistic interpretation of this deactivation based on short-range thermally activated atomic movements of the dopants to form sulfur complexes.
Authors:
; ; ;  [1] ;  [2] ; ;  [3]
  1. Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States)
  2. University of Ottawa, Ottawa, Ontario K1N 6N5 (Canada)
  3. Harvard School of Engineering and Applied Sciences, Cambridge, Massachusetts 02138 (United States)
Publication Date:
OSTI Identifier:
22217723
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 114; Journal Issue: 24; Other Information: (c) 2013 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ABSORPTION; ACTIVATION ENERGY; ANNEALING; DEACTIVATION; DIFFUSION; DOPED MATERIALS; ENERGY BEAM DEPOSITION; ION IMPLANTATION; LASER RADIATION; MELTING; METASTABLE STATES; MONOCRYSTALS; PHOTONS; SILICON; SOLID SOLUTIONS; SULFUR; SULFUR COMPLEXES