Abstract

arak tespit edilmiştir. 620℃'de üretilen 0,90 Cu/(Ga+In) oranına sahip numune % 14,23 ile en iyi verimlilik değerini göstermiştir.

Determination of optimum Cu/(Ga+In) ratio at different fabrication temperatures for Cu(In,Ga)(Se,Te)2 thin film solar cells

Abstract

In this study, tellurium-dopped Cu(In,Ga)(Se,Te)2 completed solar cells with different Cu/(Ga+In) ratios were fabricated at different substrate temperatures and investigated to understand the effect of Cu/(Ga+In) ratio on the solar parameters and the structure of the solar cells. It was found that the Cu/(Ga+In) ratio affected the short circuit current and fill factor more than the open circuit voltage by changing the microstructure. Therefore, the increase in the current collection and short circuit current density had a greater effect on the efficiency value. Increasing the Cu/(Ga+In) ratio from 0.88 to 0.90 decreased the average grain size from 0.47 µm to 0.38 µm at 480℃ substrate temperature. However, further increasing the Cu/(Ga+In) ratio from 0.90 to 0.92 made the structure more compact having an average grain size of 0.41 µm with less thin film quality. The samples with highest Cu/(Ga+In) ratios having the most compact structures in their temperature groups showed very low current collection through all wavelengths when compared to other samples. The short circuit current density results were found to be in consistency with the external quantum efficiency graphs of the completed solar cell samples. Optimum Cu/(Ga+In) values for the samples produced at 480℃ and 620℃ substrate temperatures were found to be 0.88 and 0.90, respectively. The sample with 0.90 CGI ratio which produced at 620℃ performed the best efficiency with 14.23 %.

Keywords

• Solar cell
• Thin film
• Tellurium
• CGI ratio

References

1. [1] Minoura S, Kodera K, Maekawa T, Miyazaki K, Niki S, Fujiwara H. Dielectric function of Cu(In, Ga)Se2-based polycrystalline materials. Journal of Applied Physics 2013; 113: 063505.
2. [2] Bulbul S, Ertugrul G, Arli F. Investigation of usage potentials of global energy systems, International Advanced Researches and Engineering Journal 2018; 2: 58-67.
3. [3] Başol BM, Kapur VK, Leidholm CR, Halani A, Gledhill K. Flexible and lightweight copper indium diselenide solar cells on polyimide substrates. Solar Energy Materials and Solar Cells 1996; 43: 93-98.
4. [4] Conibeer GJ, Willoughby A. Solar cell materials: Developing technologies. John Wiley and Sons Ltd, England, 2014.
5. [5] Lee TD, Ebong AU. A review of thin film solar cell technologies and challenges. Renewable and Sustainable Energy Reviews 2017; 70: 1286-1297.
6. [6] Jäger-Waldau A. Status and perspectives of thin film photovoltaics - Thin film solar cells: Current status and future trends. Nova Science Publishers Inc, New York, US, 2010.
7. [7] Poortmans J, Arkhipov V. Thin film solar cells: Fabrication, characterization, and applications. John Wiley & Sons, West Sussex, England, 2006.
8. [8] Naghavi N, Mollica F, Goffard J, Posada J, Duchatelet A, Jubault M, Donsanti F, Cattoni A, Collin S, Grand PP, Greffet JJ, Lincot D. Ultrathin Cu(In,Ga)Se2 based solar cells. Thin Solid Films 2017; 633: 55-60.

9. [9] Sun Y, Lin S, Li W, Cheng S, Zhang Y, Liu Y, Liu W. Review on alkali element doping in Cu(In,Ga)Se2 thin films and solar cells. Engineering 2017; 3: 452-459.
10. [10] Fiat S, Bacaksiz E, Kompitsas M, Çankaya G. Temperature and tellurium (Te) dependence of electrical characterization and surface properties for a chalcopyrite structured schottky barrier diode. Journal of Alloys and Compounds 2014; 585: 178-184.
11. [11] Fiat S, Koralli P, Bacaksiz E, Giannakopoulos KP, Kompitsas M, Manolakos DE, Çankaya G. The influence of stoichiometry and annealing temperature on the properties of CuIn0.7Ga0.3Se2 and CuIn0.7Ga0.3Te2 thin films. Thin Solid Films 2013; 545: 64-70.
12. [12] Dumrul H, Arlı F, Taşkesen E. Dust Effect on PV Modules: Its Cleaning Methods. Innovative Research in Engineering 2023; 183-200.
13. [13] Ağca S, Çankaya G. Photovoltaic properties of Cu(In,Ga)(Se,Te)2 thin film solar cells with different tellurium amounts and a copper-poor stoichiometry. International Journal of Energy Studies 2023; 8(4): 849-858.
14. [14] Ağca S, Çankaya G. Effect of gallium content on diode characteristics and solar cell parameters of Cu(In1-xGax)(Se0.98Te0.02)2 thin film solar cells produced by three-stage co-evaporation at low temperature. Gazi University Journal of Science Part C: Design and Technology 2023; 11(4): 1108-1115.
15. [15] Ağca S, Çankaya G, Sonmezoglu S. Impact of tellurium as an anion dopant on the photovoltaic performance of wide-bandgap Cu(In,Ga)Se2 thin-film solar cells with rubidium fluoride post-deposition treatment. Frontiers in Energy Research 2023; 11: 1215712.
16. [16] Fiat S, Polat I, Bacaksiz E, Çankaya G, Koralli P, Manolakos DE, Kompitsas M. Optical and structural properties of nanostructured CuIn0.7Ga0.3(Se(1−x)Tex)2 chalcopyrite thin films—Effect of stoichiometry and annealing. Journal of Nanoscience and Nanotechnology 2014; 14: 5002-5010.
17. [17] Varol SF, Bacaksiz E, Koralli P, Kompitsas M, Çankaya G. A novel nanostructured CuIn0.7Ga0.3(Se0.4Te0.6)2/SLG multinary compounds thin films: For photovoltaic applications. Materials Letters 2015; 142: 273-276.
18. [18] Fiat S, Polat İ, Bacaksiz E, Kompitsas M, Çankaya G. The influence of annealing temperature and tellurium (Te) on electrical and dielectrical properties of Al/p-CIGSeTe/Mo Schottky diodes. Current Applied Physics 2013; 13: 1112-1118.
19. [19] Varol SF, Bacaksız E, Çankaya G, Kompitsas M. Optical, structural, and morphological characterization of CuIn0.7Ga0.3(Se0.6Te0.4)2 thin films under different annealing temperatures. Celal Bayar University Journal of Science 2013; 9: 9-16.
20. [20] Atasoy Y, Başol B, Olğar M, Tomakin M, Bacaksız E. Cu(In,Ga)(Se,Te)2 films formed on metal foil substrates by a two-stage process employing electrodeposition and evaporation. Thin Solid Films 2018; 649: 30-37.
21. [21] Atasoy Y, Başol B, Polat İ, Tomakin M, Parlak M, Bacaksız E. Cu(In,Ga)(Se,Te)2 pentenary thin films formed by reaction of precursor layers. Thin Solid Films 2015; 592: 189-194.
22. [22] Kodigala SR. Cu(In1-xGax)Se2 Based Thin Film Solar Cells. Massachusetts: Academic Press, USA, 2011.
23. [23] Thompson JO, Anderson MD, Ngai T, Allen T, Johnson DC. Nucleation and growth kinetics of co-deposited copper and selenium precursors to form metastable copper selenides. Journal of Alloys and Compounds 2011; 509: 9631-9637.
24. [24] Liao KH, Su CY, Ding YT, Koo HS. Microstructural characterization of CIGS formation using different selenization processes. Applied Surface Science 2013; 270: 139-144.
25. [25] Scholtz L, Ladanyi, L, Mullerova J. Influence of surface roughness on optical characteristics of multilayer solar cells. Advances in Electrical and Electronic Engineering 2015; 12: 631-638.
26. [26] Singh R, Parashar M, Sandhu S, Yoo K, Lee JJ. The effects of crystal structure on the photovoltaic performance of perovskite solar cells under ambient indoor illumination. Solar Energy 2021; 220: 43-50.
27. [27] Saive R. Light trapping in thin silicon solar cells: A review on fundamentals and Technologies. Progress in Photovoltaics: Research and Applications 2021; 29:1125-1137.
28. [28] Gloeckler M, Sites JR, Metzger WK. Grain-boundary recombination in Cu(In,Ga)Se2 solar cells. Journal of Applied Physics 2005; 98: 113704.
29. [29] Guirdjebaye N, Ngoupo AT, Ouedraogo S, Tcheum GLM, Ndjaka JMB. Numerical analysis of CdS-CIGS interface configuration on the performances of Cu(In,Ga)Se2 solar cells. Chinese Journal of Physics 2020; 67: 230-237.
30. [30] Chen SH, Lin WT, Chan SH, Tseng SZ, Kuo CC, Hu SC, Peng WH, Lu YT. Photoluminescence analysis of CdS/CIGS interfaces in CIGS solar cells. ECS Journal of Solid State Science and Technology 2015; 4: 347-350.