Investigation of density of states and charge carrier mobility in amorphous semiconductors via time-of-flight photocurrent analysis
DOI:
https://doi.org/10.5488/cmp.28.43801Keywords:
amorphous selenium (a-Se), time-of-flight (ToF), transient photocurrent (TPC), Laplace transform analysis, multiple trapping model (MTM), density of states (DOS)Abstract
The present study examines the electronic transport characteristics of amorphous semiconductors through ToF measurements and numerical simulations. The primary objective is to determine the DOS in amorphous selenium (a-Se) and to assess the temperature and electric field dependence of the hole mobility. A comprehensive investigation of localized states within the mobility gap is performed using Laplace transform analysis of ToF photocurrent transients, combined with the multiple trapping model. This approach enables accurate reconstruction of the DOS across a wide temperature range, allowing clear identification of shallow and deep trap levels and revealing thermally activated transport mechanisms. Simulated ToF currents are also used to evaluate the hole drift mobility under various thermal and field conditions. Activation energies are extracted from Arrhenius plots of the mobility data. The results support a physically consistent description of the electronic structure in a-Se and validate the applicability of Laplace-based techniques for probing charge transport in disordered semiconductors.References
Spear W. E., Proc. Phys. Soc., 1960, 76, 826. DOI: https://doi.org/10.1088/0370-1328/76/6/302
Schmidlin F. W., Phys. Rev. B, 1977, 16, 2362. DOI: https://doi.org/10.1103/PhysRevB.16.2362
Noolandi J., Phys. Rev. B, 1977, 16, 4466. DOI: https://doi.org/10.1103/PhysRevB.16.4466
Schmidlin F. W., Philos. Mag. B, 1980, 41, 535. DOI: https://doi.org/10.1080/13642818008245405
Kastner M. A., Solid State Commun., 1983, 45, 191. DOI: https://doi.org/10.1016/0038-1098(83)90374-5
Serdouk F., Benkhedir M. L., Physica B, 2015, 459, 122. DOI: https://doi.org/10.1016/j.physb.2014.12.002
Serdouk F., Boumali A., Makhlouf A., Benkhedir M. L., Rev. Mex. Fis., 2020, 66, 643–655. DOI: https://doi.org/10.31349/RevMexFis.66.643
Serdouk F., Boumali A., Sibatov R. T., Fractal Fract., 2023, 7, 243. DOI: https://doi.org/10.3390/fractalfract7030243
Goutal Y., Serdouk F., Boumali A., Benkhedir M. L., Theor. Math. Phys., 2024, 219, 839–855. DOI: https://doi.org/10.1134/S0040577924050118
Ohno A., Hanna J., Dunlap D. H., Jpn. J. Appl. Phys., 2008, 47, 1079. DOI: https://doi.org/10.1143/JJAP.47.1079
Naito H., Ding J., Okuda M., Appl. Phys. Lett., 1994, 64, 1830. DOI: https://doi.org/10.1063/1.111769
Naito H., Nagase T., Ishii T., Okuda M., Kawaguchi T., Maruno S., J. Non-Cryst. Solids, 1996, 363, 198–200. DOI: https://doi.org/10.1016/0022-3093(95)00725-3
Ogawa N., Nagase T., Naito H., J. Non-Cryst. Solids, 2000, 367, 266–269. DOI: https://doi.org/10.1016/S0022-3093(99)00732-2
Nagase T., Naito H., J. Non-Cryst. Solids, 1998, 824, 227–230. DOI: https://doi.org/10.1016/S0022-3093(98)00163-X
Benkhedir M. L., Aida M. S., Adriaenssens G. J., J. Non-Cryst. Solids, 2004, 344, 193. DOI: https://doi.org/10.1016/j.jnoncrysol.2004.08.062
Benkhedir M. L., Brinza M., Adriaenssens G. J., J. Phys.: Condens. Matter, 2004, 16, No. 44, S5253. DOI: https://doi.org/10.1088/0953-8984/16/44/022
Qamhieh N., Benkhedir M. L., Brinza M., Willekens J., Adriaenssens G. J., J. Phys.: Condens. Matter, 2004.
Benkhedir M. L., Brinza M., Adriaenssens G. J., Main C., J. Phys.: Condens. Matter, 2008, 20, 215202. DOI: https://doi.org/10.1088/0953-8984/20/21/215202
Benkhedir M. L., Djefaflia F., Mansour M., Qamhieh N., Phys. Status Solidi C, 2010, 7, No. 3–4, 877–880. DOI: https://doi.org/10.1002/pssc.200982846
Koughia K., Shakoor Z., Kasap S. O., Marshall J. M., J. Appl. Phys., 2005, 97, No. 3, 033706. DOI: https://doi.org/10.1063/1.1835560
Kasap S., Koughia C., Berashevich J., Johanson R., Reznik A., J. Mater. Sci.: Mater. Electron., 2015, 26, 4644–4658. DOI: https://doi.org/10.1007/s10854-015-3069-1
Benkhedir M. L., Defect Levels in the Amorphous Selenium Band Gap, Ph.d. thesis, Katholieke Universiteit Leuven, Belgium, 2006.
Emelianova E. V., Benkhedir M. L., Brinza M., Adriaenssens G. J., J. Appl. Phys., 2006, 99, No. 8, 083702. DOI: https://doi.org/10.1063/1.2187395
van Rossum G., Drake F. L., Python 3 Reference Manual, CreateSpace, Scotts Valley, CA, 2009.
Gill W. D., J. Appl. Phys., 1972, 43, 5033. DOI: https://doi.org/10.1063/1.1661065
Marshall J. M., Owen A. E., Phys. Status Solidi A, 1972, 12, 181. DOI: https://doi.org/10.1002/pssa.2210120119
Kasap S. O., Juhasz C., J. Phys. D: Appl. Phys., 1985, 18, 703. DOI: https://doi.org/10.1088/0022-3727/18/4/015
Fogal B., Kasap S., Can. J. Phys., 2014, 92, No. 7, 634–639. DOI: https://doi.org/10.1139/cjp-2013-0524
Hill R. M., Philos. Mag., 1971, 23, 59. DOI: https://doi.org/10.1080/14786437108216365
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