Volume-9 , Issue-3 , Dec 2022, ISSN 2348-6341 Go Back

• Open Access   Article

  Study Over Electronic and Optical Properties of Semiconductors in Nanometric Regime

  H.I. Ikeri, V.M. Adokor, N.N. Tasie

  Research Paper | Journal-Paper (JPCM)

  Vol.9 , Issue.3 , pp.1-7, Dec-2022

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  Abstract
  Electronic and optical properties of semiconductors in nanometric regime have been simulated using the potential well concept and solving 3D Schrodinger equation. We calculated the optical bandgap and wavelength for varying sizes of semiconductor quantum dots QDs. The result shows a size-dependent absorption and fluorescence spectra with discrete electronic transitions that can be modified by size modulation. As a result, they exhibit excellent photoelectronic properties, including broad excitation spectra with narrow emission bands, and so can be used for multiplexed detection without overlap of spectral emission. They also possess wide band bandgap energies and have shown significant changes in their optical transitions with bandgap tuning. This illustration is in the outstanding blueshift of absorption bands as well as the photoluminescence spectra with decreasing size. These properties represent a signature of discrete electronic state, which is, in turn, a direct consequence of the quantum confinement effect. The optical spectra observed for CdSe and CdS QDs span nearly the entire visible region which makes them excellent fluorescent materials for improving display performance such as color gamut. In addition, near-infrared (NIR) waveband also observed in CdSe and CdS QDs cover the biological transparency windows and are widely explored for biological imaging applications following their deeper tissue penetration and higher spatial resolution compare to visible probes. The optical waveband observed in InAs, InSb QDs covers the short-wavelength infrared spectral region suitable for optical communication operating exclusively in C-band, at which chromatic dispersion and transmission losses in optical fibers are at a respective minimum. Furthermore, InAs, InSb QDs strongly indicate spectrum covering the important atmospheric transmission windows where attenuation of electromagnetic wave is extremely low particularly for free space communications. It is found that PbS, PbSe and PbSe QDs display exceptional optical trait that can be tuned throughout UV to IR wavebands, favorable for quantitative gain in solar cells applications.

  Key-Words / Index Term
  Semiconductor nanocrystals, confinement, potential well, Schrodinger equation, electronic and optical properties

  References
  [1] Y. W. Jun, C. S. Choi, and J. Cheon. Size and shape controlled ZnTe nanocrystals with quantum confinement effect. Chem. Commun. 7(1): 101–102, 2001.
  [2] A. I. Onyia, H. I. Ikeri, and A. I. Chima. Surface and Quantum Effects in Nanosized Semiconductor, American Journal of Nano Research and Applications. Vol. 8, No. 3, pp. 35-41, 2020.
  [3] S. T. Harry, and M. A. Adekanmbi. Confinement Energy of Quantum Dots and the Brus Equation. International Journal of Research -Granthaalayah, 8(11), 318-323, 2020.
  [4] M. Cardona, and Y. Peter. Fundamentals of semiconductors, fourth edition, springer. 2013
  [5] U. Bockelmann. Exciton relaxation and radiative recombination in semiconductor quantum dots. Physical Review B-Condensed Matter, 48(23): 17637- 17640, 1993.
  [6] Y. Arakawa, Y. Nagamune, M. Nishioka, and S. Tsukamoto. Physics of semiconductor. Journal of Science and Technology, 8(6): 1082- 1088, 1993.
  [7] E. Chukwuocha, and M. Onyeaju. Effect of quantum confinement on the wavelength of CdSe quantum dots. International journal of science and technology research, 1(7): 21 – 24, 2012.
  [8] P. Nisha, and D. Amrita. Theoretical study of dependence of wavelength on size of quantum dot. Intl Journal of Scientific Research and Development, 4(1): 126 – 130, 2016.
  [9] H. Davies. The physics of low dimensional semiconductors; an introduction (6th Reprint Ed.) Cambridge university press, 234, 2006.
  [10] S. Madan, G. Monika, and D. Kamal. Size and shape effects on the band gap of semiconductor compound nanomaterials. Journal of Taibah University for Science, 12(4): 470-475, 2018.
  [11] J. Harbold, and P. Monica. The electronic and optical properties of colloidal lead selenide semiconductor nanocrystal: Ph.D. dissertation. Cornel University. Ithaca, New York. 2008.
  [12] H. I. Ikeri, and A. I. Onyia. Theoretical investigation of size effect on energy gap of quantum dots using particle in a box model. Chalcogenide Letters, 14(2): 49 – 54, 2017.
  [13] H. I. Ikeri, A. I. Onyia, and P. U. Asogwa. Investigation of optical properties of quantum dots for multiple junction solar cells applications. Intl. Journal of scientific and technology, 8(10): 3531 – 3535, 2019.
  [14] L. E. Brus. Electron-electron and electron-hole interactions in small semiconductor crystallites: the size dependence of the lowest excited electronic state. The Journal of ChemicalPhysics, 80(9): 403-4409, 1984.
  [15] C. Delerue, and M. Lannoo. Nanostructures: Theory and modelling. India: Springer, 245 – 265, 2004.
  [16] G. Jia. Excitons properties and quantum confinement in CdS/ZnS core/shell quantum dots. Opt. Adv. Mater, 5: 738–741, 2011.
  [17] H. I. Ikeri, and A. I. Onyia. Formulation of exciton in a quantum box model for multiple exciton solar cell application. Intl. Journal of Scientific Research in Physics and Applied Science, 7(2): 12 – 16, 2020.

  Citation
  H.I. Ikeri, V.M. Adokor, N.N. Tasie, "Study Over Electronic and Optical Properties of Semiconductors in Nanometric Regime," Journal of Physics and Chemistry of Materials, Vol.9, Issue.3, pp.1-7, 2022

• Open Access   Article

  Synthesis, Optical and Electrical Conductivity Characterization of Micro-thick Titanium Dioxide Thin Film Semiconductor

  A.O. Ohiani, K.M. Omatola, A.S. Ayodele, J. Adeyemi

  Research Paper | Journal-Paper (JPCM)

  Vol.9 , Issue.3 , pp.8-12, Dec-2022

  Abstract

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  Abstract
  The synthesis of micro-thick titanium dioxide thin film semiconducting material on indium-tin oxide substrate by spin-coating technique and the reliance of its optical transmittance, absorbance, band-gap and electrical conductivity on the film thickness have been investigated. The film thickness was determined with the aid of a surface profiler. The electrical conductivity was determined using a four point probe. An UV-VIS-NIR Spectrophotometer was employed to study the optical transmittance, absorbance and the band-gap energy of the titanium dioxide material. The study revealed a direct relationship between the electrical conductivity and the film thickness. The film transmittance was observed to vary inversely with film thickness and the film absorption coefficients while the band-gap of the film displayed a direct relationship with film thickness.

  Key-Words / Index Term
  Micro-thick, TiO2 Thin film, Synthesis, Conductivity, Transmittance and Band-gap

  References
  [1] M. I. Khan, K. A. Bhatti, R. Qindeel, H. S. Althobaiti, N. Alonizan, “Structural, Electrical and Optical Properties of Multilayer TiO2 Thin Films Deposited by Sol–gel Spin Coating”, Results in Physics, vol. 7, Issue. 4, pp. 1437–1439, 2017.
  [2] S. Ito, T. N. Murakami, P. Comte, P. Liska, C. Gratzel, M. K. Nazeeruddin, and M. Gratzel, “Fabrication of thin film dye sensitized solar cells with solar to electric power conversion efficiency over 10%”, Thin Solid Films, Vol. 516, issue. 14, pp. 4613-4619, 2008.
  [3] A. Ramadoss and S. J. Kim, “Vertically aligned TiO2 Nanorod Arrays for Electrochemical Super-capacitor”, Journal of Alloys Compounds, Vol. 561, pp. 262-267, 2013.
  [4] D. Bhattacharyya, N. K. Sahoo, S. Thakur, and N. S. Das, “Spectroscopic Ellipsometry of TiO2 Layers Prepared by Ion-assisted Electron-beam Evaporation”, Thin Solid Films, Vol. 360, issue. 1-2, PP. 96-102, 2000.
  [5] D. L. Domtau, J. Simiyu, E. O. Ayieta, B. Muthoka, and J. M. Mwabora, “Optical and Electrical Properties Dependence on Thickness of Screen-Printed TiO2 Thin Films”, Journal of Materials Physics and Chemistry, vol. 4, Issue. 1, pp. 1-3, 2016.
  [6] Z. Ding, X. Hu, P. L. Yue, G. Q. Lu and P. F. Greenfield, “Synthesis of Anatase TiO2 Supported on Porous Solids by Chemical Vapor Deposition”, Catal Today, Vol. 68, Issue. 173, 2001.
  [7] Q. Zhang and C. Li, “Pure Anatase Phase Titanium Dioxide Films Prepared by Mist Chemical Vapor Deposition”, Nanomaterials, Vol. 8, Issue. 10, pp. 827, 2018.
  [8] G. Govindasamy, P. Murugasen and S. Sagadevan, “Investigations on the Synthesis, Optical and Electrical Properties of TiO2 Thin Films by Chemical Bath Deposition (CBD) method”, Materials Research, Vol. 19, Issue., 2, pp. 413-419, 2016.
  [9] D. M. Hausmann and R. G. Gordon, “Surface Morphology and Crystallinity Control in the Atomic Layer Deposition (ALD) of Hafnium and Zirconium oxide”, Journal of Crystal Growth, Vol. 249, pp. 251–261, 2003.
  [10] L. F. K. Pedrinia, L. C. Escaliante and L. V. A. Scalvi, “Deposition of TiO2 thin Films by Dip-Coating Technique from a Two-Phase Solution Method and Application to Photocatalysis”, Materials Research, Vol. 24, issue. 1, pp. 1-11, 2021.
  [11] S. Takeda, S. Suzuki, H. Odaka, and H. Hosono, “Photocatalytic TiO2 thin film deposition onto glass by DC magnetron sputtering”, Thin Solid Films, Vol. 392, issue. 2, pp. 338-344, 2001.
  [12] B. R. Weinberger and R. B. Garber, “Titanium-dioxide photocatalysts produced by reactive magnetron sputtering’’, Applied Physics Letters, Vol. 66, issue. 18, pp. 2409-2411, 1995.
  [13] C. J. Brinkers, G. C. Frey, A. J. Hurd, and C. S. Ashly, “Fundamentals of sol-gel dip coating”, Thin Solid Films, Vol. 201, issue. 1, pp. 97-108, 1991.
  [14] F. Zeribi, A. Attaf, Z. A. Derbali, H. Saidi, L. Benmebrouk, M. S. Aida, M. Dahnoun, R. Nouadji and H. Ezzaouia, “Dependence of the Physical Properties of Titanium Dioxide (TiO2) Thin Films Grown by Sol-Gel (Spin-Coating) Process on Thickness”, Journal of Solid State Science and Technology, Vol. 11, Issue. 2, pp. 30, 2022.
  [15] Z. Wang and X. Hu., “Fabrication and electrochromic properties of spin-coated TiO2 thin films from peroxo-polytitanic acid”, Thin Solid Films, Vol. 352, issue. 2, pp. 62-65, 1999.
  [16] K. Nagaveni, M. S. Hegde, N. Ravishankar, G. N. Subbanna, and G. Madras, “Synthesis and structure of nanocrystalline TiO2 with lower bandgap showing high photocatalytic activity”, Langmuir, Vol. 20, issue. 7, pp. 2900-7, 2004.
  [17] J. Yu, X Zhao, J. Du and W. Chen, “Preparation, microstructure and photocatalytic activity of the porous TiO2 anatase coating by sol-gel processing”, Journal of Sol–Gel Science and Technology, Vol. 17, issue. 2, pp. 163-171, 2000.
  [18] A. Yildiz, S. B. Lisesivdin, M. Kasap, D. Mardare, “Electrical Properties of TiO2 thin films’’, Journal of Non-Crystalline Solids, Vol. 354 pp. 4944–4947, 2008.

  Citation
  A.O. Ohiani, K.M. Omatola, A.S. Ayodele, J. Adeyemi, "Synthesis, Optical and Electrical Conductivity Characterization of Micro-thick Titanium Dioxide Thin Film Semiconductor," Journal of Physics and Chemistry of Materials, Vol.9, Issue.3, pp.8-12, 2022