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Title: Investigations on optoelectronic transition mechanisms of silicon nanoporous pillar array by using surface photovoltage spectroscopy and photoluminescence spectroscopy

Abstract

We report the electronic transition mechanisms for hydrothermally prepared silicon nanoporous pillar array (Si-NPA), investigated by surface photovoltage (SPV) spectroscopy and photoluminescence (PL) spectroscopy. By comparing the SPV spectra of single crystal silicon (sc-Si) with that of Si-NPA, the silicon nano-crystallites (nc-Si)/SiO{sub x} nanostructure in the Si-NPA could produce SPV in the wavelength range of 300–580 nm. And 580 nm (∼2.14 eV) was considered as the absorption edge of the nc-Si/SiO{sub x} nanostructure. After the sample was annealed and oxidized in air at different temperatures, both the SPV in the wavelength range of 300–580 nm and the PL emission band around 690 nm from the nc-Si/SiO{sub x} nanostructure weakened and disappeared as the annealing temperature increased from 100 to 500 °C. But both the red-infrared PL band (>710 nm) and the violet-blue PL band were enhanced by increasing the annealing temperature. After 2 years of natural oxidation in air, the SPV features for sc-Si disappeared completely, and the SPV characteristics of the nc-Si/SiO{sub x} nanostructure could be clearly observed. After analysis, the Si–O structure related localized states at the nc-Si/SiO{sub x} interface dominated the electronic transitions during the red PL emission and the SPV for the nc-Si/SiO{sub x} nanostructure in Si-NPA, the red–infrared PL was due tomore » the Si=O structure related electronic transitions, and the violet-blue PL emission could attribute to the oxygen-related defect related recombination of the photo induced carriers.« less

Authors:
; ;  [1]
  1. Department of Physics and Laboratory of Material Physics, Zhengzhou University, Zhengzhou 450001 (China)
Publication Date:
OSTI Identifier:
22271151
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 115; Journal Issue: 12; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; 77 NANOSCIENCE AND NANOTECHNOLOGY; ANNEALING; CHARGE CARRIERS; COMPARATIVE EVALUATIONS; EMISSION SPECTROSCOPY; HYDROTHERMAL SYNTHESIS; INTERFACES; MONOCRYSTALS; NANOSTRUCTURES; OXIDATION; OXYGEN; PHOTOLUMINESCENCE; RECOMBINATION; SILICON; SILICON OXIDES; SURFACES; TEMPERATURE DEPENDENCE

Citation Formats

Hu, Zhen-Gang, E-mail: huzhengang@zzu.edu.cn, Tian, Yong-Tao, and Li, Xin-Jian. Investigations on optoelectronic transition mechanisms of silicon nanoporous pillar array by using surface photovoltage spectroscopy and photoluminescence spectroscopy. United States: N. p., 2014. Web. doi:10.1063/1.4869801.
Hu, Zhen-Gang, E-mail: huzhengang@zzu.edu.cn, Tian, Yong-Tao, & Li, Xin-Jian. Investigations on optoelectronic transition mechanisms of silicon nanoporous pillar array by using surface photovoltage spectroscopy and photoluminescence spectroscopy. United States. doi:10.1063/1.4869801.
Hu, Zhen-Gang, E-mail: huzhengang@zzu.edu.cn, Tian, Yong-Tao, and Li, Xin-Jian. 2014. "Investigations on optoelectronic transition mechanisms of silicon nanoporous pillar array by using surface photovoltage spectroscopy and photoluminescence spectroscopy". United States. doi:10.1063/1.4869801.
@article{osti_22271151,
title = {Investigations on optoelectronic transition mechanisms of silicon nanoporous pillar array by using surface photovoltage spectroscopy and photoluminescence spectroscopy},
author = {Hu, Zhen-Gang, E-mail: huzhengang@zzu.edu.cn and Tian, Yong-Tao and Li, Xin-Jian},
abstractNote = {We report the electronic transition mechanisms for hydrothermally prepared silicon nanoporous pillar array (Si-NPA), investigated by surface photovoltage (SPV) spectroscopy and photoluminescence (PL) spectroscopy. By comparing the SPV spectra of single crystal silicon (sc-Si) with that of Si-NPA, the silicon nano-crystallites (nc-Si)/SiO{sub x} nanostructure in the Si-NPA could produce SPV in the wavelength range of 300–580 nm. And 580 nm (∼2.14 eV) was considered as the absorption edge of the nc-Si/SiO{sub x} nanostructure. After the sample was annealed and oxidized in air at different temperatures, both the SPV in the wavelength range of 300–580 nm and the PL emission band around 690 nm from the nc-Si/SiO{sub x} nanostructure weakened and disappeared as the annealing temperature increased from 100 to 500 °C. But both the red-infrared PL band (>710 nm) and the violet-blue PL band were enhanced by increasing the annealing temperature. After 2 years of natural oxidation in air, the SPV features for sc-Si disappeared completely, and the SPV characteristics of the nc-Si/SiO{sub x} nanostructure could be clearly observed. After analysis, the Si–O structure related localized states at the nc-Si/SiO{sub x} interface dominated the electronic transitions during the red PL emission and the SPV for the nc-Si/SiO{sub x} nanostructure in Si-NPA, the red–infrared PL was due to the Si=O structure related electronic transitions, and the violet-blue PL emission could attribute to the oxygen-related defect related recombination of the photo induced carriers.},
doi = {10.1063/1.4869801},
journal = {Journal of Applied Physics},
number = 12,
volume = 115,
place = {United States},
year = 2014,
month = 3
}
  • Highlights: • CdS/Si nanoheterostructure array has been fabricated through a CBD method. • The electronic properties have been investigated by the I–V and C–V techniques. • The onset voltages, characteristic frequency and built-in potential are investigated. • The electronic structures can be tuned through the annealing treatments. - Abstract: The electronic properties of heterostructures are very important to its applications in the field of optoelectronic devices. Understanding and control of electronic properties are very necessary. CdS/Si nanoheterostructure array have been fabricated through growing CdS nanocrystals on the silicon nanoporous pillar array using a chemical bath deposition method. The electronic propertiesmore » of CdS nanoheterostructure array have been investigated by the current–voltage, complex impedance spectroscopy and capacitance–voltage techniques. The onset voltages, characteristic frequency and built-in potential are gradually increased with increasing the annealing temperature. It is indicated that the electronic structures of CdS/Si nanoheterostructure array can be tuned through the annealing treatments.« less
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