DOI: https://doi.org/10.15587/1729-4061.2019.156565

Development of a technique for restoring the efficiency of film ITO/CdS/CdTe/Cu/Au SCs after degradation

Natalya Deyneko, Pavlo Kovalev, Oleg Semkiv, Igor Khmyrov, Roman Shevchenko

Abstract


A study into the influence of direct polarity on the output parameters of ITO/CdS/CdTe/Cu/Au solar cells (SC) has been conducted. We have experimentally registered the effect of an electric field of direct polarity on the output parameters and light diode characteristics of ITO/CdS/CdTe/Cu/Au SCs, which underwent a degradation of efficiency. When a shaded SE is exposed for not less than 120 minutes to the electric field, induced by an external DC voltage of magnitude (0.5‒0.9) V, whose polarity corresponds to the forward bias of n-p heterojunction, there is an increase in efficiency coefficient. This becomes possible if, during degradation of the instrument structure, such defects did not have time to develop, which, over the specified time of exposure, lead to resettable alternating electric microbreakdowns. It has been established that an increase in efficiency coefficient comes at the expense of the increased density of a photocurrent, decreased sequential and increased shunt resistances of SC. Improvement of diode characteristics occurs due to several physical processes. When a SC is fed a forward bias voltage, an electric field forms inside the diode structure of SC, which amplifies the built-in electric field of the rear р-р+ heterojunction and suppresses the built-in electric field of the frontal n+-p heterojunction. That occurs because the diodes are turned on towards each other. The magnitude of a forward bias voltage must not exceed the height of the potential barrier in a heterojunction. In this case, at the rear р-р+ heterojunction and in its adjoining areas from both sides the processes will be intensified that are associated with the transport of copper atoms, the restructuring of complexes of point defects containing copper, and the phase transformations of Cu1,4Te into Cu2-xTe. In addition, under the influence of the field induced by a forward bias voltage, the CuCd- particles from the depletion area of a CdS layer will start moving towards the absorber. That should reduce the resistance part of the CdS layer and lead to a decrease in the depletion area width from the absorber's side, thereby increasing the spectral sensitivity of SC in the shortwave and medium-wave fields of solar spectrum. Electrodiffusion of additional amount of CuCd- to the absorber must enhance the above-described and related effect of the increased spectral sensitivity and thus Jph of instruments. Based on the conducted research, we have constructed an algorithm for restoring the efficiency of ITO/CdS/CdTe/Cu/Au SCs and for rejecting the irrevocably degraded instrumental structures included in a running module

Keywords


cadmium telluride solar cell degradation; recovery technique; output parameters; light diode characteristics

References


Nardone, M., Albin, D. S. (2015). Degradation of CdTe Solar Cells: Simulation and Experiment. IEEE Journal of Photovoltaics, 5 (3), 962–967. doi: https://doi.org/10.1109/jphotov.2015.2405763

Khrypunov, G., Vambol, S., Deyneko, N., Sychikova, Y. (2016). Increasing the efficiency of film solar cells based on cadmium telluride. Eastern-European Journal of Enterprise Technologies, 6 (5 (84)), 12–18. doi: https://doi.org/10.15587/1729-4061.2016.85617

Deyneko, N., Semkiv, O., Soshinsky, O., Streletc, V., Shevchenko, R. (2018). Results of studying the Cu/ITO transparent back contacts for solar cells SnO2:F/CdS/CdTe/Cu/ITO. Eastern-European Journal of Enterprise Technologies, 4 (5 (94)), 29–34. doi: https://doi.org/10.15587/1729-4061.2018.139867

Deyneko, N., Khrypunov, G., Semkiv, O. (2018). Photoelectric Processes in Thin-film Solar Cells Based on CdS/CdTe with Organic Back Contact. Journal of Nano- and Electronic Physics, 10 (2), 02029-1–02029-4. doi: https://doi.org/10.21272/jnep.10(2).02029

Murashev, V. N., Legotin, S. A., Krasnov, A. A., Dudkin, A. A., Zezin, D. A. (2013). Degradation of three–junction amorphous Si:H based solar cells. Izvestiya Vysshikh Uchebnykh Zavedenii. Materialy Elektronnoi Tekhniki = Materials of Electronics Engineering, 4, 39–42. doi: https://doi.org/10.17073/1609-3577-2013-4-39-42

Zezin, D. A., Latohin, D. V. (2012). Ocenka nekotoryh faktorov, vliyayushchih na degradaciyu solnechnyh elementov na osnove a-Si:H. Amorfnye i mikrokristallicheskie poluprovodniki: sbornik trudov VIII Mezhdunarodnoy konferencii. Sankt-Peterburg: Izd-vo Politekhn. un-ta, 26–27.

Wronski, C. R., Pearce, J. M., Koval, R. J., Niu, X., Ferlauto, A. S., Koh, J., Collins, R. W. (2002). Light Induced Defect Creation Kinetics in Thin Film Protocrystalline Silicon Materials and Their Solar Cells. MRS Proceedings, 715. doi: https://doi.org/10.1557/proc-715-a13.4

Karpov, V. G., Shvydka, D., Roussillon, Y. (2005). Physics of CdTe Photovoltaics: from Front to Back. MRS Proceedings, 865. doi: https://doi.org/10.1557/proc-865-f10.1

Demtsu, S. H., Albin, D. S., Sites, J. R., Metzger, W. K., Duda, A. (2008). Cu-related recombination in CdS/CdTe solar cells. Thin Solid Films, 516 (8), 2251–2254. doi: https://doi.org/10.1016/j.tsf.2007.08.035

Albin, D. S. (2008). Accelerated stress testing and diagnostic analysis of degradation in CdTe solar cells. Reliability of Photovoltaic Cells, Modules, Components, and Systems. doi: https://doi.org/10.1117/12.795360

McMahon, T. J., Berniard, T. J., Albin, D. S. (2005). Nonlinear shunt paths in thin-film CdTe solar cells. Journal of Applied Physics, 97 (5), 054503. doi: https://doi.org/10.1063/1.1856216

Karpov, V. G., Shvydka, D., Roussillon, Y. (2004). E2phase transition: Thin-film breakdown and Schottky-barrier suppression. Physical Review B, 70 (15). doi: https://doi.org/10.1103/physrevb.70.155332

Razykov, T. M., Ferekides, C. S., Morel, D., Stefanakos, E., Ullal, H. S., Upadhyaya, H. M. (2011). Solar photovoltaic electricity: Current status and future prospects. Solar Energy, 85 (8), 1580–1608. doi: https://doi.org/10.1016/j.solener.2010.12.002

Fang, Z., Wang, X. C., Wu, H. C., Zhao, C. Z. (2011). Achievements and Challenges of CdS/CdTe Solar Cells. International Journal of Photoenergy, 2011, 1–8. doi: https://doi.org/10.1155/2011/297350

Mazzamuto, S., Vaillant, L., Bosio, A., Romeo, N., Armani, N., Salviati, G. (2008). A study of the CdTe treatment with a Freon gas such as CHF2Cl. Thin Solid Films, 516 (20), 7079–7083. doi: https://doi.org/10.1016/j.tsf.2007.12.124

Mamazza, R., Balasubramanian, U., Morel, D. L., Ferekides, C. S. (2002). Thin films of CdIn2O4 as transparent conducting oxides. Proc. of 29th IEEE Photovoltaic Specialists Conference. Anaheim, 616–619.

Minami, T., Kakumu, T., Takeda, Y., Takata, S. (1996). Highly transparent and conductive ZnO-In2O3 thin films prepared by d.c. magnetron sputtering. Thin Solid Films, 290-291, 1–5. doi: https://doi.org/10.1016/s0040-6090(96)09094-3

Pilipenko, V. V., Kuprikov, V. I., Soznik, A. P. (2009). Microscopic nucleon–nucleus optical potential with rearrangement effects based on the effective skyrme forces. International Journal of Modern Physics E, 18 (09), 1845–1862. doi: https://doi.org/10.1142/s0218301309013907

Jeong, W.-J., Park, G.-C. (2001). Electrical and optical properties of ZnO thin film as a function of deposition parameters. Solar Energy Materials and Solar Cells, 65 (1-4), 37–45. doi: https://doi.org/10.1016/s0927-0248(00)00075-1

Deyneko, N., Semkiv, O., Khmyrov, I., Khryapynskyy, A. (2018). Investigation of the combination of ITO/CdS/CdTe/Cu/Au solar cells in microassembly for electrical supply of field cables. Eastern-European Journal of Enterprise Technologies, 1 (12 (91)), 18–23. doi: https://doi.org/10.15587/1729-4061.2018.124575

Enzenroth, R. A., Barth, K. L., Sampath, W. S. (2005). Correlation of stability to varied CdCl2 treatment and related defects in CdS/CdTe PV devices as measured by thermal admittance spectroscopy. Journal of Physics and Chemistry of Solids, 66 (11), 1883–1886. doi: https://doi.org/10.1016/j.jpcs.2005.09.022


GOST Style Citations


Nardone M., Albin D. S. Degradation of CdTe Solar Cells: Simulation and Experiment // IEEE Journal of Photovoltaics. 2015. Vol. 5, Issue 3. P. 962–967. doi: https://doi.org/10.1109/jphotov.2015.2405763 

Increasing the efficiency of film solar cells based on cadmium telluride / Khrypunov G., Vambol S., Deyneko N., Sychikova Y. // Eastern-European Journal of Enterprise Technologies. 2016. Vol. 6, Issue 5 (84). P. 12–18. doi: https://doi.org/10.15587/1729-4061.2016.85617 

Results of studying the Cu/ITO transparent back contacts for solar cells SnO2:F/CdS/CdTe/Cu/ITO / Deyneko N., Semkiv O., Soshinsky O., Streletc V., Shevchenko R. // Eastern-European Journal of Enterprise Technologies. 2018. Vol. 4, Issue 5 (94). P. 29–34. doi: https://doi.org/10.15587/1729-4061.2018.139867 

Deyneko N., Khrypunov G., Semkiv O. Photoelectric Processes in Thin-film Solar Cells Based on CdS/CdTe with Organic Back Contact // Journal of Nano- and Electronic Physics. 2018. Vol. 10, Issue 2. P. 02029-1–02029-4. doi: https://doi.org/10.21272/jnep.10(2).02029 

Degradation of three–junction amorphous Si:H based solar cells / Murashev V. N., Legotin S. A., Krasnov A. A., Dudkin A. A., Zezin D. A. // Izvestiya Vysshikh Uchebnykh Zavedenii. Materialy Elektronnoi Tekhniki = Materials of Electronics Engineering. 2013. Issue 4. P. 39–42. doi: https://doi.org/10.17073/1609-3577-2013-4-39-42 

Zezin D. A., Latohin D. V. Ocenka nekotoryh faktorov, vliyayushchih na degradaciyu solnechnyh elementov na osnove a-Si:H // Amorfnye i mikrokristallicheskie poluprovodniki: sbornik trudov VIII Mezhdunarodnoy konferencii. Sankt-Peterburg: Izd-vo Politekhn. un-ta, 2012. P. 26–27.

Light Induced Defect Creation Kinetics in Thin Film Protocrystalline Silicon Materials and Their Solar Cells / Wronski C. R., Pearce J. M., Koval R. J., Niu X., Ferlauto A. S., Koh J., Collins R. W. // MRS Proceedings. 2002. Vol. 715. doi: https://doi.org/10.1557/proc-715-a13.4 

Karpov V. G., Shvydka D., Roussillon Y. Physics of CdTe Photovoltaics: from Front to Back // MRS Proceedings. 2005. Vol. 865. doi: https://doi.org/10.1557/proc-865-f10.1 

Cu-related recombination in CdS/CdTe solar cells / Demtsu S. H., Albin D. S., Sites J. R., Metzger W. K., Duda A. // Thin Solid Films. 2008. Vol. 516, Issue 8. P. 2251–2254. doi: https://doi.org/10.1016/j.tsf.2007.08.035 

Albin D. S. Accelerated stress testing and diagnostic analysis of degradation in CdTe solar cells // Reliability of Photovoltaic Cells, Modules, Components, and Systems. 2008. doi: https://doi.org/10.1117/12.795360 

McMahon T. J., Berniard T. J., Albin D. S. Nonlinear shunt paths in thin-film CdTe solar cells // Journal of Applied Physics. 2005. Vol. 97, Issue 5. P. 054503. doi: https://doi.org/10.1063/1.1856216 

Karpov V. G., Shvydka D., Roussillon Y. E2phase transition: Thin-film breakdown and Schottky-barrier suppression // Physical Review B. 2004. Vol. 70, Issue 15. doi: https://doi.org/10.1103/physrevb.70.155332 

Solar photovoltaic electricity: Current status and future prospects / Razykov T. M., Ferekides C. S., Morel D., Stefanakos E., Ullal H. S., Upadhyaya H. M. // Solar Energy. 2011. Vol. 85, Issue 8. P. 1580–1608. doi:  https://doi.org/10.1016/j.solener.2010.12.002 

Achievements and Challenges of CdS/CdTe Solar Cells / Fang Z., Wang X. C., Wu H. C., Zhao C. Z. // International Journal of Photoenergy. 2011. Vol. 2011. P. 1–8. doi: https://doi.org/10.1155/2011/297350 

A study of the CdTe treatment with a Freon gas such as CHF2Cl / Mazzamuto S., Vaillant L., Bosio A., Romeo N., Armani N., Salviati G. // Thin Solid Films. 2008. Vol. 516, Issue 20. P. 7079–7083. doi: https://doi.org/10.1016/j.tsf.2007.12.124 

Thin films of CdIn2O4 as transparent conducting oxides / Mamazza R., Balasubramanian U., Morel D. L., Ferekides C. S. // Proc. of 29th IEEE Photovoltaic Specialists Conference. Anaheim, 2002. P. 616–619.

Highly transparent and conductive ZnO-In2O3 thin films prepared by d.c. magnetron sputtering / Minami T., Kakumu T., Takeda Y., Takata S. // Thin Solid Films. 1996. Vol. 290-291. P. 1–5. doi: https://doi.org/10.1016/s0040-6090(96)09094-3 

Pilipenko V. V., Kuprikov V. I., Soznik A. P. Microscopic nucleon-nucleus optical potential with rearrangement effects based on the effective skyrme forces // International Journal of Modern Physics E. 2009. Vol. 18, Issue 09. P. 1845–1862. doi: https://doi.org/10.1142/s0218301309013907 

Jeong W.-J., Park G.-C. Electrical and optical properties of ZnO thin film as a function of deposition parameters // Solar Energy Materials and Solar Cells. 2001. Vol. 65, Issue 1-4. P. 37–45. doi: https://doi.org/10.1016/s0927-0248(00)00075-1 

Investigation of the combination of ITO/CdS/CdTe/Cu/Au solar cells in microassembly for electrical supply of field cables / Deyneko N., Semkiv O., Khmyrov I., Khryapynskyy A. // Eastern-European Journal of Enterprise Technologies. 2018. Vol. 1, Issue 12 (91). P. 18–23. doi: https://doi.org/10.15587/1729-4061.2018.124575 

Enzenroth R. A., Barth K. L., Sampath W. S. Correlation of stability to varied CdCl2 treatment and related defects in CdS/CdTe PV devices as measured by thermal admittance spectroscopy // Journal of Physics and Chemistry of Solids. 2005. Vol. 66, Issue 11. P. 1883–1886. doi: https://doi.org/10.1016/j.jpcs.2005.09.022 







Copyright (c) 2019 Natalya Deyneko, Pavlo Kovalev, Oleg Semkiv, Igor Khmyrov, Roman Shevchenko

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ISSN (print) 1729-3774, ISSN (on-line) 1729-4061