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Title: Structural and electrical studies of ultrathin layers with Si{sub 0.7}Ge{sub 0.3} nanocrystals confined in a SiGe/SiO{sub 2} superlattice

Abstract

In this work, SiGe/SiO{sub 2} multi-layer (ML) films with layer thickness in the range of a few nanometers were successfully fabricated by conventional RF-magnetron sputtering at 350 deg. C. The influence of the annealing treatment on SiGe nanocrystals (NCs) formation and crystalline properties were investigated by Raman spectroscopy and grazing incidence x-ray diffraction. At the annealing temperature of 800 deg. C, where well defined SiGe NCs were observed, a thorough structural investigation of the whole ML structure has been undertaken by Rutherford backscattering spectroscopy, grazing incidence small angle x-ray scattering, high resolution transmission electron microscopy, and annular dark field scanning transmission electron microscopy. Our results show that the onset of local modifications to the ML composition takes place at this temperature for annealing times of the order of a few tens of minutes with the formation of defective regions in the upper portion of the ML structure. Only the very first layers over the Si substrate appear immune to this problem. This finding has been exploited for the fabrication of a defect free metal-oxide-semiconductor structure with a well-defined single layer of SiGe NCs. A memory effect attributed to the presence of the SiGe NCs has been demonstrated by high frequencymore » capacitance-voltage measurements.« less

Authors:
; ; ; ;  [1];  [2]; ;  [3]; ;  [4];  [5];  [6];  [1]
  1. Centre of Physics and Physics Department, University of Minho, 4710 - 057 Braga (Portugal)
  2. CNR-IMM Sezione di Bologna, via P. Gobetti 101, 40129 Bologna (Italy)
  3. Rudjer Boskovic Institute, Bijenicka cesta 54, 10000 Zagreb (Croatia)
  4. ITN, Ion Beam Laboratory, Unit of Physics and Accelerators, E.N. 10, 2686-953 Sacavem (Portugal)
  5. Physics Department and ICEMS, University of Lisbon, 1749-016 Lisboa (Portugal)
  6. Sincrotrone Trieste, 34149 Basovizza (Italy)
Publication Date:
OSTI Identifier:
22038967
Resource Type:
Journal Article
Journal Name:
Journal of Applied Physics
Additional Journal Information:
Journal Volume: 111; Journal Issue: 10; Other Information: (c) 2012 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 0021-8979
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; 77 NANOSCIENCE AND NANOTECHNOLOGY; ANNEALING; CRYSTAL DEFECTS; CRYSTAL GROWTH; GERMANIUM ALLOYS; GERMANIUM SILICIDES; LAYERS; NANOSTRUCTURES; RAMAN SPECTRA; RAMAN SPECTROSCOPY; RUTHERFORD BACKSCATTERING SPECTROSCOPY; SEMICONDUCTOR MATERIALS; SILICON ALLOYS; SILICON OXIDES; SMALL ANGLE SCATTERING; SUBSTRATES; SUPERLATTICES; THIN FILMS; TRANSMISSION ELECTRON MICROSCOPY; X-RAY DIFFRACTION

Citation Formats

Vieira, E M. F., Martin-Sanchez, J, Rolo, A G, Levichev, S, Gomes, M J. M., Parisini, A, Buljan, M, Capan, I, Alves, E, Barradas, N P, Conde, O, Bernstorff, S, Chahboun, A, and Physics Department, FST Tanger, Tanger. Structural and electrical studies of ultrathin layers with Si{sub 0.7}Ge{sub 0.3} nanocrystals confined in a SiGe/SiO{sub 2} superlattice. United States: N. p., 2012. Web. doi:10.1063/1.4722278.
Vieira, E M. F., Martin-Sanchez, J, Rolo, A G, Levichev, S, Gomes, M J. M., Parisini, A, Buljan, M, Capan, I, Alves, E, Barradas, N P, Conde, O, Bernstorff, S, Chahboun, A, & Physics Department, FST Tanger, Tanger. Structural and electrical studies of ultrathin layers with Si{sub 0.7}Ge{sub 0.3} nanocrystals confined in a SiGe/SiO{sub 2} superlattice. United States. https://doi.org/10.1063/1.4722278
Vieira, E M. F., Martin-Sanchez, J, Rolo, A G, Levichev, S, Gomes, M J. M., Parisini, A, Buljan, M, Capan, I, Alves, E, Barradas, N P, Conde, O, Bernstorff, S, Chahboun, A, and Physics Department, FST Tanger, Tanger. 2012. "Structural and electrical studies of ultrathin layers with Si{sub 0.7}Ge{sub 0.3} nanocrystals confined in a SiGe/SiO{sub 2} superlattice". United States. https://doi.org/10.1063/1.4722278.
@article{osti_22038967,
title = {Structural and electrical studies of ultrathin layers with Si{sub 0.7}Ge{sub 0.3} nanocrystals confined in a SiGe/SiO{sub 2} superlattice},
author = {Vieira, E M. F. and Martin-Sanchez, J and Rolo, A G and Levichev, S and Gomes, M J. M. and Parisini, A and Buljan, M and Capan, I and Alves, E and Barradas, N P and Conde, O and Bernstorff, S and Chahboun, A and Physics Department, FST Tanger, Tanger},
abstractNote = {In this work, SiGe/SiO{sub 2} multi-layer (ML) films with layer thickness in the range of a few nanometers were successfully fabricated by conventional RF-magnetron sputtering at 350 deg. C. The influence of the annealing treatment on SiGe nanocrystals (NCs) formation and crystalline properties were investigated by Raman spectroscopy and grazing incidence x-ray diffraction. At the annealing temperature of 800 deg. C, where well defined SiGe NCs were observed, a thorough structural investigation of the whole ML structure has been undertaken by Rutherford backscattering spectroscopy, grazing incidence small angle x-ray scattering, high resolution transmission electron microscopy, and annular dark field scanning transmission electron microscopy. Our results show that the onset of local modifications to the ML composition takes place at this temperature for annealing times of the order of a few tens of minutes with the formation of defective regions in the upper portion of the ML structure. Only the very first layers over the Si substrate appear immune to this problem. This finding has been exploited for the fabrication of a defect free metal-oxide-semiconductor structure with a well-defined single layer of SiGe NCs. A memory effect attributed to the presence of the SiGe NCs has been demonstrated by high frequency capacitance-voltage measurements.},
doi = {10.1063/1.4722278},
url = {https://www.osti.gov/biblio/22038967}, journal = {Journal of Applied Physics},
issn = {0021-8979},
number = 10,
volume = 111,
place = {United States},
year = {Tue May 15 00:00:00 EDT 2012},
month = {Tue May 15 00:00:00 EDT 2012}
}