Kalkopirit İnce Film Güneş Hücrelerinde Yeni Çalışmalar: Gümüş Alaşımlama

Year 2024, Volume: 16 Issue: 1, 106 - 116, 31.01.2024

Semih Ağca

https://doi.org/10.29137/umagd.1368646

Abstract

Bu çalışmada, kalkopirit güneş hücreleri ile ilgili genel bilgiler verildikten sonra farklı üretim yöntemleri, güneş hücresi tabakalarına uygulanan geliştirme yöntemleri ve dünya genelinde yapılan araştırmaların durumu incelenmiştir. Kalkopirit güneş hücrelerinin %26 verim ile farklı tipteki güneş hücreleri ile yarışabilir pozisyonda olduğu gösterilmiştir. Geleneksel kalkopirit yapının son yıllarda yerini gümüş alaşımlanmış kalkopirit yapıya bıraktığı tespit edilmiştir. Gümüş alaşımlama araştırmaları gümüş alaşımlanmış kalkopirit yapının geleneksel kalkopirit yapıya kıyasla aynı üretim sıcaklıklarında daha iyi tane büyümesi sergilediğini göstermiştir. Bu durum da kristal kalitesinin artmasını sağlamıştır. Ayrıca, gümüş alaşımlama ile yasak bant aralığının genişletilebilmesi çok katlı tandem güneş hücresi çalışmalarına katkıda bulunmuştur. Geniş yasak bant aralığı çalışmalarına yapmış olduğu en büyük katkı kalkopirit yapıdaki galyumun dağılımının kontrol edilebilmesini sağlamasıdır. Bununla birlikte, gümüş alaşımlama rekombinasyonu azaltıp açık devre voltajını artırdığı için daha iyi verim sonuçları alınmıştır. Bu teknoloji ile şeffaf ve esnek güneş hücresi tasarlanabiliyor olması da çok önemlidir. Kalkopirit güneş hücreleri ile ilgili çalışmaların geleceğinin gümüş alaşımlama ile şekilleneceği öngörülmektedir. Hem esnek hem de şeffaf güneş hücrelerinin giyilebilir güneş hücresi, bina uygulamaları ve tarım arazilerinde kullanılabilen agrivoltaik gibi alanlarda kullanılabileceği gerçeği konunun önemini artırmaktadır.

Keywords

Gümüş alaşımlama, Kalkopirit, İnce film, Güneş hücresi

New Studies on Chalcopyrite Thin Film Solar Cells: Silver Alloying

Abstract

In this study, after giving general information about chalcopyrite solar cells, different production methods, development methods applied to solar cell layers and the status of research conducted around the world are examined. It has been shown that chalcopyrite solar cells can compete with different types of solar cells with an efficiency of 26%. It has been determined that the traditional chalcopyrite structure has been replaced by silver alloyed chalcopyrite structure in recent years. Silver alloying research has shown that the silver alloyed chalcopyrite structure exhibits better grain growth at the same production temperatures compared to the traditional chalcopyrite structure. This has enabled the crystal quality to increase. Additionally, widening the bandgap by silver alloying has contributed to multilayer tandem solar cell studies. The biggest contribution of silver alloying to wide bandgap studies is the ability to control the distribution of gallium in the chalcopyrite structure. Moreover, better efficiency results were obtained because silver alloying reduced recombination and increased the open circuit voltage. It is also very important that transparent and flexible solar cells can be designed with this technology. It is predicted that the future of studies on chalcopyrite solar cells will be shaped by silver alloying. The fact that both flexible and transparent solar cells can be used in areas such as wearable solar cells, building applications and agrivoltaics that can be used in agricultural lands increases the importance of the subject.

Keywords

Silver alloying, Chalcopyrite, Thin film, Solar cell

References

• Aboulfadl, H., Sopiha, K. V., Keller, J., Larsen, J. K., Scragg, J. J. S., Persson, C., Thuvander, M., & Edoff, M. (2021). Alkali dispersion in (Ag,Cu)(In,Ga)Se2 thin film solar cells – Insight from theory and experiment. ACS Applied Materials & Interfaces, 13, 7188-7199. doi:10.1021/acsami.0c20539
• Acciarri, M., Le Donne, A., Marhionna, S., Meschia, M., Parravicini, J., Gasparotto, A., & Binetti, S. (2018). CIGS thin films grown by hybrid sputtering-evaporation method: Properties and PV performance. Solar Energy, 175, 16-24. doi:10.1016/j.solener.2018.02.024
• Bommersbach, P., Arzel, L., Tomassini, M., Gautron, E., Leyder, C., Urien, M., Dupuy, D., & Barreau, N. (2013). Influence of Mo back contact porosity on co-evaporated Cu(In,Ga)Se2 thin film properties and related solar cell. Progress in Photovoltaics: Research and Applications, 21(3), 332-343. doi:10.1002/pip.1193
• Bothwell, A. M., Li, S., Farshchi, R., Miller, M. F., Wands, J., Perkins, C. L., Rockett, A., Arehart, A. R., & Kuciauskas, D. (2022). Large-area (AgCu)(InGa)Se2 thin-film solar cells with increased bandgap and reduced voltage losses realized with bulk defect reduction and front-grading of the absorber bandgap. Solar RRL, 2200230. doi:10.1002/solr.202200230
• Boyle, J. H., McCandless, B. E., Hanket, G. M., & Shafarman, W. N. (2011). Structural characterization of the (AgCu)(InGa)Se2 thin film alloy system for solar cells. Thin Solid Films, 519, 7292-7295. doi:10.1016/j.tsf.2011.01.138
• Boyle, J. H., McCandless, B. E., Shafarman, W. N., & Birkmire, R. W. (2014). Structural and optical properties of (Ag,Cu)(In,Ga)Se2 polycrystalline thin film alloys. Journal of Applied Physics, 115, 223504. doi:10.1063/1.4880243
• Cheng, K., Shen, X., Liu, J., Liu, X., & Du, Z. (2021). Sputtered Ag-alloyed Cu(In,Ga)(Se,S)2 solar cells by sequential process. Solar Energy, 217, 70-77. doi:10.1016/j.solener.2021.01.056
• Chirila, A., Reinhard, P., Pianezzi, F., Bloesch, P., Uhl, A. R., Fella, C., Kranz, L., Keller, D., Gretener, C., Hagendorfer, H., Jaeger, D., Erni, R., Nishiwaki, S., Buecheler, S., & Tiwari, A. N. (2013). Potassium-induced surface modification of Cu(In,Ga)Se2 thin films for high-efficiency solar cells. Nature Materials, 12, 1107-1111. doi:10.1038/NMAT3789
• Chu, V. B., Cho, J. W., Park, S. J., Hwang, Y. J., Park, H. K., Do, Y. R., & Min, B. K. (2014). Fabrication of solution processed 3D nanostructured CuInGaS2 thin film solar cells. Nanotechnology, 25, 125401. doi:10.1088/0957-4484/25/12/125401
• Dabbabi, S., Nasr, T. B., & Kamoun, N. K. (2019). CIGS solar cells for space applications: Numerical simulation of the effect of traps created by high-energy electron and proton irradiation on the performance of solar cells. The Journal of The Minerals, Metals & Materials Society, 71, 602-607. doi:10.1007/s11837-018-2748-9
• Delgado-Sanchez, J-M., Lopez-Gonzalez, J. M., Orpella, A., Sanchez-Cortezon, E., Alba, M. D., Lopez-Lopez, C., & Alcubilla, R. (2017). Front contact optimization of industrial scale CIGS solar cell for low solar concentration using 2D physical modeling. Renewable Energy, 101, 90-95. doi:10.1016/j.renene.2016.08.046
• Donzel-Gargand, O., Larsson, F., Törndahl, T., Stolt, L., & Edoff, M. (2018). Secondary phase formation and surface modification from a high dose KF-post deposition treatment of (Ag,Cu)(In,Ga)Se2 solar cell absorbers. Progress in Photovoltaics: Research and Applications, 27, 220-228. doi:10.1002/pip.3080
• Edoff, M., Jarmar, T., Nilsson, N. S., Wallin, E., Högstrom, D., Stolt, O., Lundberg, O., Shafarman, W. N., & Stolt, L. (2017). High Voc in (Cu,Ag)(In,Ga)Se2 solar cells. IEEE Journal of Photovoltaics, 7(6), 1789-1794. doi:10.1109/JPHOTOV.2017.2756058
• Erslev, P. T., Hanket, G. M., Shafarman, W. N., & Cohen, J. D. (2009). Characterizing the effects od silver alloying in chalcopyrite CIGS solar cells with junction capacitance methods. Materials Research Society Symposium Proceedings, 1165, 107. doi:10.1557/PROC-1165-M01-07
• Erslev, P. T., Lee, J. W., Hanket, G. M., Shafarman, W. N., & Cohen, J. D. (2011). The electronic structure of Cu(In1-xGax)Se2 alloyed with silver. Thin Solid Films, 519, 7296-7299. doi:10.1016/j.tsf.2011.01.368
• Feurer, T., Reinhard, P., Avancini, E., Bissig, B., Löckinger, J., Fuchs, P., Carron, R., Weiss, T. P., Perrenoud, J., Stutterheim, S., Buecheler, S., & Tiwari, A. N. (2017). Progress in CIGS thin film photovoltaics – Research and development, manufacturing, and applications. Progress in Photovoltaics: Research and Applications, 25, 645-667. doi:10.1002/pip.2811
• Gloeckler, M., & Sites, J. R. (2005). Band-gap grading in Cu(In,Ga)Se2 solar cells. Journal of Physics and Chemistry of Solids, 66, 1891-1894. doi:10.1016/j.jpcs.2005.09.087
• Hagiwara, Y., Nakada, T., & Kunioka, A. (2001). Improved Jsc in CIGS thin film solar cells using a transparent conducting ZnO:B window layer. Solar Energy Materials & Solar Cells, 67, 267-271. doi:10.1016/S0927-0248(00)00291-9
• Hamtaei, S., Brammertz, G., Meuris, M., Poortmans, J., & Vermang, B. (2021). Dominant processing factors in two-step fabrication of pure sulfide CIGS absorbers. Energies, 14, 4737. doi:10.3390/en14164737
• Hanket, G. M., Boyle, J. H., Shafarman, W. N., & Teeter, G. (2010). Wide-bandgap (AgCu)(InGa)Se2 absorber layers deposited by three-stage co-evaporation. 35th IEEE Photovoltaic Specialists Conference, 11625837. doi:10.1109/PVSC.2010.5614576
• Helder, T., Kanevce, A., Zinsser, M., Gutzler, R., Paetel, S., Hempel, W., Friedlmeier, T. M., & Powalla, M. (2022). How small changes make a difference: Influence of low silver contents on the effect of RbF-PDT in CIGS solar cells. Progress in Photovoltaics: Research and Applications. doi:10.1002/pip.3628
• Herz, K., Eicke, A., Kessler, F., Wachter, R., & Powalla, M. (2003). Diffusion barriers for CIGS solar cells on metallic substrates. Thin Solid Films, 431-432, 392-397. doi:10.1016/S0040-6090(03)00259-1
• Ishizaki, H., Yamada, K., Arai, R., Kuromiya, Y., Masatsugu, Y., Yamada, N., & Nakada, T. (2004). Structural properties of Ag-based chalcopyrite compound thin films for solar cells. Materials Research Society Symposium Proceedings, 865, 512. doi:10.1557/PROC-865-F5.12
• Islam, M. M., Ishizuka, S., Yamada, A., Sakurai, K., Niki, S., Sakurai, T., & Akimoto, K. (2009). CIGS solar cell with MBE-grown ZnS buffer layer. Solar Energy Materials & Solar Cells, 93, 970-972. doi:10.1016/j.solmat.2008.11.047
• Islam, M. A., Hossain, M. S., Aliyu, M. M., Chelvanathan, P., Huda, Q., Karim, M. R., Sopian, K., & Amin, N. (2013). Comparison of structural and optical properties of CdS thin films grown by CSVT, CBD and sputtering techniques. Energy Procedia, 33, 203-213. doi:10.1016/j.egypro.2013.05.059
• Jackson, P., Wuerz, R., Hariskos, D., Lotter, E., Witte, W., & Powalla, M. (2016). Effects of heavy alkali elements in Cu(In,Ga)Se2 solar cells with efficiencies up to 22.6%. Physica Status Solidi RRL, 10(8), 583-586. doi:10.1002/pssr.201600199
• Jeng, M-J., Chen, Z-Y., Xiao, Y-L., Chang, L-B., Ao, J., Sun, Y., Popko, E., Jacak, W., & Chow, L. (2015). Improving efficiency of multicrystalline silicon and CIGS solar cells by incorporating metal nanoparticles. Materials, 8, 6761-6771. doi:10.3390/ma8105337
• Kaelin, M., Rudmann, D., & Tiwari, A. N. (2004). Low cost processing of CIGS thin film solar cells. Solar Energy, 77, 749-756. doi:10.1016/j.solener.2004.08.015
• Kanevce, A., Essig, S., Paetel, S., Hempel, W., Hariskos, D., & Friedlmeier, T. M. (2022). Impact of Ag content on device properties of Cu(In,Ga)Se2 solar cells. EPJ Photovoltaics, 13, 28. doi:10.1051/epjpv/2022026
• Keller, J., Nilsson, N. S., Aijaz, A., Riekehr, L., Kubart, T., Edoff, M., & Törndahl, T. (2018). Using hydrogen-doped In2O3 films as a transparent back contact in (Ag,Cu)(In,Ga)Se2 solar cells. Progress in Phovoltaics: Research and Applications, 26, 159-170. doi:10.1002/pip.2977
• Keller, J., Sopiha, K. V., Stolt, O., Stolt, L., Persson, C., Scragg, J. J. S., Törndahl, T., & Edoff, M. (2020). Wide-gap (Ag,Cu)(In,Ga)Se2 solar cells with different buffer materials – A path to a better heterojunction. Progress in Photovoltaics: Research and Applications, 28(4), 237-250. doi:10.1002/pip.3232
• Keller, J., Stolt, L., Donzel-Gargand, O., Kubart, T., & Edoff, M. (2022). Wide-gap chalcopyrite solar cells with indium oxide-based transparent back contacts. Solar RRL, 6, 2200401. doi:10.1002/solr.202200401
• Khallaf, H., Oladeji, I. O., Chai, G., & Chow, L. (2008). Characterization of CdS thin films grown by chemical bath deposition using four different cadmium sources. Thin Solid Films, 516, 7306-7312. doi:10.1016/j.tsf.2008.01.004
• Kim, C., Rhee, I., Hwang, D-K., & Kim, D-H. (2011). Optimum substrate temperature in one-stage co-evaporation of Cu(In,Ga)Se2 thin films for high efficiency solar cells. Journal of the Korean Physical Society, 59(6), 3432-3435. doi:10.3938/jkps.59.3432
• Kim, K., Ahn, S. K., Choi, J. H., Yoo, J., Eo, Y-J., Cho, J-S., Cho, A., Gwak, J., Song, S., Cho, D-H., Chung, Y-D., & Yun, J. H. (2018). High efficirnt Ag-alloyed Cu(In,Ga)Se2 solar cells with wide bandgaps and their application to chalcopyrite-based tandem solar cells. Nano Energy, 48, 345-352. doi:10.1016/j.nanoen.2018.03.052
• Krause, M., Yang, S-C., Moser, S., Nishiwaki, S., Tiwari, A. N., & Carron, R. (2023). Silver-alloyed low-bandgap CuInSe2 solar cells for tandem applications. Solar RRL, 7, 2201122. doi:10.1002/solr.202201122
• Lisco, F., Kaminski, P. M., Abbas, A., Bass, K., Bowers, J. W., Claudio, G., Losurdo, M., & Walls, J. M. (2015). The structural properties of CdS deposited by chemical bath deposition and pulsed direct current magnetron sputtering. Thin Solid Films, 582, 323-327. doi:10.1016/j.tsf.2014.11.062
• Liu, Y., Kong, D., Li, J., Zhao, C., Chen, C., & Brugger, J. (2012). Preparation of Cu(In,Ga)Se2 thin film by solvothermal and spin-coating process. Energy Procedia, 16,217-222. doi:10.1016/j.egypro.2012.01.036
• Lu, H-T., Yang, C-Y., & Lu, C-H. (2016). Formation process and photovoltaic properties of Cu(In,Ga)Se2 and (Ag,Cu)(In,Ga)Se2 on flexible stainless steel substrates formed at different selenization temperatures. Journal of Materials Science: Materials in Electronics, 27, 10642-10649. doi:10.1007/s10854-016-5161-6
• Lu, H-T., Ou, C-Y., & Lu, C-H. (2018). (Ag,Cu)(In,Ga)Se2 thin films fabricated on flexible substrates via non-vacuum process. Journal of Materials Science: Materials in Electronics, 29, 1614-1622. doi:10.1007/s10854-017-8072-2
• Martin, N. M., Törndahl, T., Wallin, E., Simonov, K. A., Rensmo, A., & Platzer-Björkman, C. (2022). Surface/interface effects by alkali postdeposition treatments of (Ag,Cu)(In,Ga)Se2 thin film solar cells. ACS Applied Energy Materials, 5, 461-468. doi:10.1021/acsaem.1c02990
• Matur, U. C., Akyol, S., Baydoğan, N., & Cimenoglu, H. (2015). The optical properties of CIGS thin films derived by sol-gel dip coating process at different withdrawal speed. Procedia – Social and Behavioral Sciences, 195, 1762-1767. doi:10.1016/j.sbspro.2015.06.328
• Nakada, T., Yamada, K., Arai, R., Ishizaki, H., & Yamada, N. (2005). Novel wide-band-gap Ag(In1-xGax)Se2 thin film solar cells. Materials Research Society Symposium Proceedings, 865, 111. doi:10.1557/PROC-865-F11.1
• Nakada, T., Kijima, S., Kuromiya, Y., Arai, R., Ishii, Y., Kawamura, N., Ishizaki, H., & Yamada, N. (2006). Chalcopyrite thin film tandem solar cells with 1.5 V open-circuit-voltage. IEEE 4th World Conference on Photovoltaic Energy Conference, 9286444. doi:10.1109/WCPEC.2006.279474
• Oliveira, A., Curado, M., Teixeira, J., Tome, D., Çaha, I., Oliveira, K., Lopes, T., Monteiro, M., Violas, A., Correira, M., Fernandes, P., Deepak, F., Edoff, M., & Salome, P. (2023). Over 100 mV Voc improvement for rear passivated ACIGS ultra-thin solar cells. Advanced Functional Materials, 2303188. doi:10.1002/adfm.202303188
• Powalla, M., & Dimmler, B. (2000). Scaling up issues of CIGS solar cells. Thin Solid Films, 361-362, 540-546. doi:10.1016/S0040-6090(99)00849-4
• Powalla, M., Hariskos, D., Lotter, E., Oertel, M., Springer, J., Stellbogen, D., Dimmler, B., & Schaffler, R. (2003). Large-area CIGS modules: Process and properties. Thin Solid Films, 431-432, 523-533. doi:10.1016/S0040-6090(03)00255-4
• Rajan, G., Karki, S., Collins, R. W., Podraza, N. J., & Marsillac, S. (2020). Real-time optimization of anti-reflective coatings for CIGS solar cells. Materials, 13, 4259. doi:10.3390/ma13194259
• Reinhard, P., Chirila, A., Blösch, P., Pianezzi, F., Nishiwaki, S., Buecheler, S., & Tiwari, A. N. (2013). Review of progress toward 20% efficiency flexible CIGS solar cells and manufacturing issues of solar modules. IEEE Journal of Photovoltaics, 3(1), 572-580. doi:10.1109/JPHOTOV.2012.2226869
• Saifullah, M., Ahn, S., Gwak, J., Ahn, S., Kim, K., Cho, J., Park, J. H., Eo, Y. J., Cho, A., Yoo, J-S., & Yun, J. H. (2016). Development of semitransparent CIGS thin-film solar cells modified with a sulfurized-AgGa layer for building applications. Journal of Materials Chemistry A, 4, 10542-10551. doi:10.1039/c6ta01909a
• Saji, V. S., Choi, I-H., & Lee, C. W. (2011). Progress in electrodeposited absorber layer for CuIn(1-x)GaxSe2 (CIGS) solar cells. Solar Energy, 85, 2666-2678. doi:10.1016/j.solener.2011.08.003
• Schmid, M., Manley, P., Ott, A., Song, M., & Yin, G. (2016). Nanoparticles for light management in ultra-thin chalcopyrite solar cells. Journal of Materials Research, 31, 3273-3289. doi:10.1557/jmr.2016.382
• Serhan, J., Djebbour, Z., Favre, W., Migan-Dubois, A., Darga, A., Mencaraglia, D., Naghavi, N., Renou, G., Guillemoles, J-F., & Lincot, D. (2011). Investigation of the metastability behavior of CIGS based solar cells with ZnMgO-Zn(S, O, OH) window-buffer layers. Thin Solid Films, 519, 7606-7610. doi:10.1016/j.tsf.2010.12.148
• Shafarman, W. N., Thompson, C., Boyle, J., Hanket, G., Erslev, P., & Cohen, J. D. (2010). Device characterization of (AgCu)(InGa)Se2 solar cells. 35th IEEE PhotovoltaicSpecialists Conference, 11625968. doi:10.1109/PVSC.2010.5615949
• Shen, X., Yang, M., Zhang, C., Qiao, Z., Wang, H., & Tang, C. (2018). Utilizing magnetron sputtered AZO-ITO bilayer structure as transparent conducting oxide for improving the performance of flexible CIGS solar cell. Superlattices and Microstructures, 123, 251-256. doi:10.1016/j.spmi.2018.09.001
• Sheu, H-H., Hsu, Y-T., Jian, S-Y., & Liang, S-C. (2016). The effect of Cu concentration in the photovoltaic efficiency of CIGS solar cells prepared by co-evaporation technique. Vacuum, 131, 278-284. doi:10.1016/j.vacuum.2016.07.008
• Shim, B-H., Kang, J-W., Jeong, H., Jeong, Y., Kumar, T. P., Jang, J-H., & Park, S-J. (2016). Enhanced efficiency of Cu(In,Ga)Se2 solar cells with antireflection coating layers of MgF2 and ZnO nanorods. Thin Solid Films, 603, 103-107. doi:10.1016/j.tsf.2016.01.056
• Siebentritt, S., Kampschulte, T., Bauknecht, A., Blieske, U., Harneit, W., Fiedeler, U., & Lux-Steiner, M. (2002). Cd-free buffer layers for CIGS solar cells prepared by a dry process. Solar Energy Materials & Solar Cells, 70(4), 447-457. doi:10.1016/S0927-0248(01)00035-6
• Soltanmohammad, S., Chen, L., McCandless, B. E., & Shafarman W. N. (2017). Phase stability in Ag-Cu-In-Ga metal precursors for (Ag,Cu)(In,Ga)Se2 thin films. Solar Energy Materials and Solar Cells, 172, 347-352. doi:10.1016/j.solmat.2017.08.009
• Sopiha, K. V., Larsen, J. K., Donzel-Gargand, O., Khavari, F., Keller, J., Edoff, M., Platzer-Björkman, C., Persson, C., & Scragg, J. J. S. (2020). Thermodynamic stability, phase separation and Ag grading in (Ag,Cu)(In,Ga)Se2 solar absorbers. Journal of Materials Chemistry A, 8, 8740-8751. doi:10.1039/d0ta00363h
• Sun, Y., Lin, S., Li, W., Cheng, S., Zhang, Y., Liu, Y., & Liu, W. (2017). Review on alkali element doping in Cu(In,Ga)Se2 thin films and solar cells. Engineering, 3, 452-459. doi:10.1016/J.ENG.2017.04.020
• Thompson, C. P., Chen, L., Shafarman, W. N., Lee, J., Fields, S., & Birkmire, R. W. (2015). Bandgap gradients in (Ag,Cu)(In,Ga)Se2 thin film solar cells deposited by thre—stage co-evaporation. IEEE 42nd Photovoltaic Specialist Conference, 15664747. doi:10.1109/PVSC.2015.7355692
• Valdes, N. H., Lee, J. W., & Shafarman, W. N. (2018). Ag alloying and KF treatment effects on low bandgap CIGS solar cells. IEEE 7th World Conference on Photovoltaic Energy Conversion, 18288577. doi:10.1109/PVSC.2018.8547372
• Valdes, N. H., Jones, K. J., Opila, R. L., & Shafarman, W. N. (2019). Influence Ga and Ag on the KF treatment chemistry for CIGS solar cells. IEEE Journal of Photovoltaics, 9(6), 1846-1851. doi:10.1109/JPHOTOV.2019.2930210
• Van Deelen, J., Omar, A., & Barink, M. (2017). Optical desing of textured thin film CIGS solar cells with nearly-invisible nanowire assisted front contacts. Materials, 10, 392. doi:10.3390/ma10040392
• Wakefield, G., Adair, M., Gardener, M., Greiner, D., Kaufmann, C. A., & Moghal, J. (2015). Mesoporous silica nanocomposite antireflective coating for Cu(In,Ga)Se2 thin film solar cells. Solar Energy Materials & Solar Cells, 134, 359-363. doi:10.1016/j.solmat.2014.12.022
• Wang, C., Zhuang, D., Zhao, M., Li, Y., Dong, L., Wang, H., Wei, J., & Gong, Q. (2022-a). Effect of siler doping on properties of Cu(In,Ga)Se2 films prepared by CuInGa precursors. Journal of Energy Chemistry, 66, 218-225. doi:10.1016/j.jechem.2021.08.008
• Wang, C., Hu, Z., Liu, Y., Cheng, S., Yao, Y., Zhang, Y., Yang, X., Zhou, Z., Liu, F., Zhang, Y., Sun, Y., & Liu, W. (2022-b). Wide bandgap CIGS thin films via Ag-PDT to ameliorate the interface quality of CIGS/CdS heterojunction. Journal of Materials Science: Materials in Electronics, 33, 11055-11066. doi:10.1007/s10854-022-08083-2
• Warasawa, M., Kaijo, A., & Sugiyama, M. (2012). Adventages of using amorphous zinc oxide films for window layer in Cu(In,Ga)Se2 solar cells. Thin Solid Films, 520, 2119-2122. doi:10.1016/j.tsf.2011.08.093
• Wu, J-J., Yang, C-Y., Sung, J-C., & Lu, C-H. (2015). Nonvacuum solution synthesis of (Ag,Cu)(In,Ga)Se2 absorbers for applications in thin-film solar cells. Journal of American Ceramic Society, 98(12), 3911-3917. doi:10.1111/jace.13818
• Wu, J-J., Yang, C-Y., & Lu, C-H. (2016). Preparation and characterization of silver doped Cu(In,Ga)Se2 films via nonvacuum solution process. Journal of American Ceramic Society, 99(10), 3280-3285. doi:10.1111/jace.14339
• Xu, C., Zhang, H., Parry, J., Perera, S., Long, G., & Zeng, H. (2013). A single source three-stage evaporation approach to CIGS absorber layer for thin film solar cells. Solar Energy Materials & Solar Cells, 117, 357-362. doi:10.1016/j.solmat.2013.06.006
• Yadav, B. S., Day, S. R., & Dhage, S. R. (2017). Chalcopyrite CIGS absorber layer by inkjet printing for photovoltaic application. Materials Today: Proceedings, 4, 12480-12483. doi:10.1016/j.matpr.2017.10.047
• Yamada, K., Hoshino, N., & Nakada, T. (2006). Crystallographic and electrical properties of wide gap Ag(In1-xGax)Se2 thin films and solar cells. Science and Technology of Advanced Materials, 7, 42-45. doi:10.1016/j.stam.2005.11.016
• Yang, S-C., Sastre, J., Krause, M., Sun, X., Hertwig, R., Ochoa, M., Tiwari, A. N., & Carron, R. (2021). Silver-promoted high-performance (Ag,Cu)(In,Ga)Se2 thin-film solar cells grown at very low temperature. Solar RRL, 5(5), 2100108. doi:10.1002/solr.202100108
• Yang, S-C., Lin, T-Y., Ochoa, M., Lai, H., Kothandaraman, R., Fu, F., Tiwari, A. N., Carron, R. (2023). Efficiency boost of bifacial Cu(In,Ga)Se2 thin-film solar cells for flexible and tandem applications with silver-assisted low-temperature process. Nature Energy, 8, 40-51. doi:10.1038/s41560-022-01157-9
• Zhang, Y., Hu, Z., Lin, S., Cheng, S., He, Z., Wang, C., Zhou, Z., Sun, Y., & Liu, W. (2020). Facile silver-incorporated method of tuning the back gradient of Cu(In,Ga)Se2 films. ACS Applied Energy Materials, 3(10), 9963-9971. doi:10.1021/acsaem.0c01644
• Zhang, Y., Shi, L., Wang, Z., Dai, H., Hu, Z., Zhou, S., Chen, H., Feng, X., Zhu, J., Sun, Y., Liu, W., & Zhang, Q. (2021). Silver-assisted optimization of band gap gradient structure of Cu(In,Ga)Se2 solar cells via SCAPS. Solar Energy, 227, 334-342. doi:10.1016/j.solener.2021.09.011