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Title: Structural and optical properties of silicon rich oxide films in graded-stoichiometric multilayers for optoelectronic devices

Abstract

Silicon nanocrystals (Si-ncs) are excellent candidates for the development of optoelectronic devices. Nevertheless, different strategies are still necessary to enhance their photo and electroluminescent properties by controlling their structural and compositional properties. In this work, the effect of the stoichiometry and structure on the optical properties of silicon rich oxide (SRO) films in a multilayered (ML) structure is studied. SRO MLs with silicon excess gradually increased towards the top and bottom and towards the center of the ML produced through the variation of the stoichiometry in each SRO layer were fabricated and confirmed by X-ray photoelectron spectroscopy. Si-ncs with three main sizes were observed by a transmission electron microscope, in agreement with the stoichiometric profile of each SRO layer. The presence of the three sized Si-ncs and some oxygen related defects enhances intense violet/blue and red photoluminescence (PL) bands. The SRO MLs were super-enriched with additional excess silicon by Si{sup +} implantation, which enhanced the PL intensity. Oxygen-related defects and small Si-ncs (<2 nm) are mostly generated during ion implantation enhancing the violet/blue band to become comparable to the red band. The structural, compositional, and luminescent characteristics of the multilayers are the result of the contribution of the individual characteristics ofmore » each layer.« less

Authors:
;  [1]; ; ;  [2];  [3]
  1. Electronics Department, INAOE, Apdo. 51, Puebla, Pue. 72000, México (Mexico)
  2. Centro de Investigación en Materiales Avanzados S.C., Unidad Monterrey-PIIT, Apodaca, NL 66628, México (Mexico)
  3. Instituto de Microelectrónica de Barcelona, IMB-CNM (CSIC), Bellaterra 08193, Barcelona (Spain)
Publication Date:
OSTI Identifier:
22594464
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 109; Journal Issue: 3; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; COMPARATIVE EVALUATIONS; DEFECTS; ELECTROLUMINESCENCE; FILMS; ION IMPLANTATION; LAYERS; NANOSTRUCTURES; OPTICAL PROPERTIES; OPTOELECTRONIC DEVICES; OXYGEN; PHOTOLUMINESCENCE; SILICON; SILICON IONS; STOICHIOMETRY; TRANSMISSION ELECTRON MICROSCOPY; X-RAY PHOTOELECTRON SPECTROSCOPY

Citation Formats

Palacios-Huerta, L., Aceves-Mijares, M., Cabañas-Tay, S. A., Cardona-Castro, M. A., Morales-Sánchez, A., E-mail: alfredo.morales@cimav.edu.mx, and Domínguez-Horna, C. Structural and optical properties of silicon rich oxide films in graded-stoichiometric multilayers for optoelectronic devices. United States: N. p., 2016. Web. doi:10.1063/1.4959080.
Palacios-Huerta, L., Aceves-Mijares, M., Cabañas-Tay, S. A., Cardona-Castro, M. A., Morales-Sánchez, A., E-mail: alfredo.morales@cimav.edu.mx, & Domínguez-Horna, C. Structural and optical properties of silicon rich oxide films in graded-stoichiometric multilayers for optoelectronic devices. United States. doi:10.1063/1.4959080.
Palacios-Huerta, L., Aceves-Mijares, M., Cabañas-Tay, S. A., Cardona-Castro, M. A., Morales-Sánchez, A., E-mail: alfredo.morales@cimav.edu.mx, and Domínguez-Horna, C. 2016. "Structural and optical properties of silicon rich oxide films in graded-stoichiometric multilayers for optoelectronic devices". United States. doi:10.1063/1.4959080.
@article{osti_22594464,
title = {Structural and optical properties of silicon rich oxide films in graded-stoichiometric multilayers for optoelectronic devices},
author = {Palacios-Huerta, L. and Aceves-Mijares, M. and Cabañas-Tay, S. A. and Cardona-Castro, M. A. and Morales-Sánchez, A., E-mail: alfredo.morales@cimav.edu.mx and Domínguez-Horna, C.},
abstractNote = {Silicon nanocrystals (Si-ncs) are excellent candidates for the development of optoelectronic devices. Nevertheless, different strategies are still necessary to enhance their photo and electroluminescent properties by controlling their structural and compositional properties. In this work, the effect of the stoichiometry and structure on the optical properties of silicon rich oxide (SRO) films in a multilayered (ML) structure is studied. SRO MLs with silicon excess gradually increased towards the top and bottom and towards the center of the ML produced through the variation of the stoichiometry in each SRO layer were fabricated and confirmed by X-ray photoelectron spectroscopy. Si-ncs with three main sizes were observed by a transmission electron microscope, in agreement with the stoichiometric profile of each SRO layer. The presence of the three sized Si-ncs and some oxygen related defects enhances intense violet/blue and red photoluminescence (PL) bands. The SRO MLs were super-enriched with additional excess silicon by Si{sup +} implantation, which enhanced the PL intensity. Oxygen-related defects and small Si-ncs (<2 nm) are mostly generated during ion implantation enhancing the violet/blue band to become comparable to the red band. The structural, compositional, and luminescent characteristics of the multilayers are the result of the contribution of the individual characteristics of each layer.},
doi = {10.1063/1.4959080},
journal = {Applied Physics Letters},
number = 3,
volume = 109,
place = {United States},
year = 2016,
month = 7
}
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