Very famous low-cost methods such as electrodeposition (ED), screen printing, and chemical spraying (CS) are done around 450°C and classified as low temperature processes. startingPage /S /GTS_PDFA1 They found in films the presence of precipitates attributed to ZnS phases which contribute to high series resistance and reduced VOC and FF values of solar cell. The performance of the proposed CdTe solar cell structure is compared with other plasmonic nanoparticle based solar cells. internal << The low cell efficiency was attributed to high series resistance and high shunt conductance which strongly affected mainly the VOC and FF values. This is also being developed for thin film applications. 2015-05-20T12:39:58+05:30 It is a form of photoelectric cell, defined as a device whose electrical characteristics, such as current, voltage, or resistance, vary when exposed to light. TCOs with band gaps of above 3 eV are the most appropriate for front electrical contact due to their optical transparency (greater than 85%) and reasonably good electrical conductivity. It is proved that CdTe is not only stable for terrestrial applications, but it has also been demonstrated that CdTe has excellent stability under high energy-photon and electron irradiation for space applications which is superior to Si, GaAs, CIGS, etc. doi Fig. /quotesingle 96 /grave 128 /bullet /dagger /daggerdbl /ellipsis /emdash /endash In addition, it is possible to produce thin film solar cells on flexible materials, including fabrics that might be used for clothing. As with most thin-film solar technologies, carrier collection is accomplished by drift, or field-assisted collection. Cell Structure The band diagram for the high-efficiency CdTe solar cells at CSU with estimated band offsets is shown in Fig. Cross section of a cadmium telluride (CdTe) thin film solar cell. CdTe-based thin-film solar cell modules currently represent one of the fastest-growing segments of commercial module production. internal /Type /Pages Kurihara et al. O’Connor and D. Phillips, Time-Correlated Single Photon Counting (Academic Press, San Diego, CA, 1984). OriginalDocumentID Copper Indium Gallium di-Selenide or Cu(InGa)Se2 or CIGS is one of the best absorber materials available owing to its high absorption coefficient and wide spectral response. This element provides the url for an article or unit of content. uuid:6b80c034-7bc1-42c5-b6e6-5159fbb0e097 The tin layer was then directly deposited on the copper layer using an alkaline solution containing stannous chloride, sodium hydroxide, and sorbitol [121]. NREL is a national laboratory of the U.S. Department of Energy, Office of Energy Efficiency & Renewable Energy, operated by the Alliance for Sustainable Energy, LLC. The CdTe is most attractive for its chemical simplicity and the robust stability. << CrossmarkDomainExclusive It is quite notable that even though important dissimilarities exist, the performances attained are independent to processing illustrating the versatility of CdTe and its superior prospects in the PV technologies. CdTe thin-film photovoltaic solar cells can be assembled easily and as long as they are an economical replacement for traditional silicon-based photovoltaic technologies. CdTe has long been well known as a leading thin-film PV material due to its near optimum bandgap of 1.44 eV and high absorption coefficient. Michael Carmody and Angelo Gilmore . >> NOTE: PRISM recommends against the use of the #other value allowed in the PRISM Platform controlled vocabulary. CdTe thin-film PV solar cells can be assembled rapidly and as long as an economical substitute for conventional silicon-based PV technologies. Schematic view of CdS/CdTe thin-film solar cell. The intrinsic (i) form of a-Si thin film can be doped as p-type or n-type to form a p-n junction, however, initial p-n junction device trials could not result in a solar cell action. the URL). Finally, annealing temperatures were elevated to 550–590°C in sulfur vapor for 5–15 minutes. internal 13 0 obj We also characterize the structural and chemical changes throughout the CdSeTe/CdTe device by Auger-electron spectroscopy (AES) profiling, electron backscatter diffraction (EBSD) on … The short circuit current was reached up to the value of 37.6 ± 0.8 mA/cm2 from 20.3 ± 0.6 mA/cm2, as shown in Fig. 44.16 illustrates the different morphologies of sequential depositions of three layers. The bandgap of CdTe directly influences the quantum efficiency of CdTe solar cells as shown in Fig. the open circuit voltage (Voc) of CdTe NC solar cells has stagnated below 0.7 V, which is significantly lower than most CdTe thin film solar cells fabricated by vacuum technology (around 0.8 V~0.9 V). external A power conversion efficiency of 11.25% was obtained with an open-circuit voltage of 0.72 V, as shown in Table 2.4 [21]. endobj stream The CdTe TF can be deposited using a number of processes and needs good stoichiometric at over 400°C. Fig. /OutputIntents [6 0 R] CdTe solar cells in the superstrate configuration have achieved record efficiencies of 16% but those in the substrate configuration have reached efficiencies of only 7.8%. This is usually a metallic layer such as nickel–aluminum. >> >> The cells depicted in Fig. studied the impact of unstirred precursor solution on the film uniformity. internal Processes in which Cd compounds are used or produced in the form of fine fumes or particles present larger hazards to health. /Kids [24 0 R] http://prismstandard.org/namespaces/basic/2.0/ This is known as “CdCl2 treatment” or “junction activation” treatment and efficiency increases by a factor of 3–5. /Nums [0 16 0 R] 12 0 obj >> In one case or another, kesterite CZTS growth resulted from the solid-state reaction between Cu2SnS3 and ZnS phases, which started at relatively high temperatures of 570°C. The downside of this technology is the processing of the absorber at relatively higher temperatures >450°C. Amendment of PDF/A standard seq Text /Type /Metadata Title of the magazine, or other publication, in which a resource was/will be published. 18.2 gives the schematics of CdTe solar cell grown on TCO coated glass substrate in a superstrate configuration. URI ScienceDirect ® is a registered trademark of Elsevier B.V. ScienceDirect ® is a registered trademark of Elsevier B.V. URL: https://www.sciencedirect.com/science/article/pii/B9780128114797000105, URL: https://www.sciencedirect.com/science/article/pii/B9780128196106000028, URL: https://www.sciencedirect.com/science/article/pii/B9780128040041000099, URL: https://www.sciencedirect.com/science/article/pii/B9780128133514000468, URL: https://www.sciencedirect.com/science/article/pii/B9780124095489100922, URL: https://www.sciencedirect.com/science/article/pii/B9780128029534000020, URL: https://www.sciencedirect.com/science/article/pii/B9780128099216000355, URL: https://www.sciencedirect.com/science/article/pii/B978012811479700018X, URL: https://www.sciencedirect.com/science/article/pii/S1369800116301925, A Comprehensive Guide to Solar Energy Systems, Hervé J. Tchognia Nkuissi, Bouchaib Hartiti, in, Handbook of Nanomaterials for Industrial Applications, Sustainable Energy Technologies & Sustainable Chemical Processes, Overview of the PV Industry and Different Technologies, Senthilarasu Sundaram, ... Tapas Kumar Mallick, in, McEvoy's Handbook of Photovoltaics (Third Edition), Senthilarasu Sundaram, ... Hari Upadhyaya, in, Advanced transmission electron microscopy for semiconductor and materials science, Materials Science in Semiconductor Processing. http://www.aiim.org/pdfa/ns/id/ This has been possible with the introduction of undoped ZnO instead of CdS buffer layer and coevaporation of NaxSe during the CIGS deposition. /PageLabels 7 0 R endobj /doi (10.1007/s11664-015-3829-y) Electrochemical deposition of metals and alloys involves the reduction of metals ions from aqueous, organic, or fused-salt electrolytes. internal endobj Mirrors crossmark:DOI /OutputCondition (sRGB) It was found that to synthesize effective CZTS films from electrodeposition route using a layered metal precursor, it is necessary to start with a nonstoichiometric initial precursor composition [for instance the Cu/(Zn+Sn) ratio must be as low as 0.7]. A highly crystalline single CZTS phase was observed from X-ray diffraction measurements. These observations inspired the development of a post deposition treatment (PDT) which led to increased efficiencies of >20% [16–18]. /Metadata 3 0 R DOI 1-x. Adobe PDF Schema CdTe solar cells clearly have a lot going for them but there remains a number of key technological challenges that, if overcome, could push the conversion efficiencies closer to the theoretical maximum of >30%. Despite the market remaining dominated by silicon, CdTe now accounts for around a 7% market share [1] and is the first of the second generation thin film technologies to effectively make the leap to truly mass deployment. 11 0 obj << CrossmarkDomainExclusive Text Abstract: In this study, ex situ spectroscopic ellipsometry was applied to investigate the optical properties and structure of the thin film CdTe solar cell and its component layer materials. The Cu treatment was performed by thermally evaporating a ~4 nm thick Cu layer before depositing a Au back contact layer, and then annealing at 150 °C for 45 min in a dry air ambient. crossmark /Range [0.0 1.0 0.0 1.0 0.0 1.0] Solution processed CdTe/CdSe nanocrystal solar cells with more than 5.5% efficiency by using an inverted device structure. SourceModified >> The nature of the manufacturing technique means that much larger area cells can be made than are possible with crystalline silicon. For some years now, to improve the Several research works are going on to increase the efficiency of inorganic PV devices. Copyright © 2021 Elsevier B.V. or its licensors or contributors. http://ns.adobe.com/pdf/1.3/ In lieu of using #other please reach out to the PRISM group at [email protected] to request addition of your term to the Platform Controlled Vocabulary. The structure of CdTe solar cell is similar in structure as above. The back contact was activated by rapid thermal processing (RTP), resulting in spectacular improvement in key device performance indicators. Text Device efficiencies on the lab scale have now exceed 22% [3] and modules have reached 18.6%, in excess of multicrystalline silicon modules (Fig. The viability of this method for fabricating PV devices has been demonstrated by BP appolo process for CdTe solar cells [118] and by CISEL project for the development of Cu (In, Ga)(S, Se)2 solar cells via electrodeposition route followed by thermal annealing [119]. Lacking detailed assessments for individual compounds, OSHA considers all cadmium compounds to be toxic, and, as a general guidance, all facilities working with any such compounds should control the indoors concentrations of CdTe dust or fumes to below the Permissible Exposure Level-Time Weighted Average (PEL-TWA) concentration of 0.005 mg/m3. So far, the highest efficiencies have been achieved in “superstrate” configuration for CdTe. internal part One drawback of very large-scale deployment of CdTe or CuInGaSe2 is the availability of the elemental constituents. << Most commonly, CH3NH3PbI3 based organic–inorganic perovskite materials have been used in these types of solar cells due to their high charge carrier mobility. Date when document was last modified default The NREL solar cell efficiency chart. A similar procedure to fabricate CZTS solar cells by solid-state reaction of electroplated Cu–Zn–Sn precursors was done by Ennaoui et al. http://crossref.org/crossmark/1.0/ The Digital Object Identifier for the article. Cadmium sulfide (CdS) is a most common n-type window layer with energy band gap of 2.4 eV. /Differences [24 /breve /caron /circumflex /dotaccent /hungarumlaut /ogonek /ring /tilde 39 Akhtaruzzaman, in Encyclopedia of Sustainable Technologies, 2017. Superstrate structures were investigated in early 80s but efficiency was below 5%. We use cookies to help provide and enhance our service and tailor content and ads. Subcontract Report NREL/SR-5200-51380 . The most common CdTe solar cells consist of a simple p-n heterojunction structure containing a p-doped CdTe layer matched with an n-doped cadmium sulfide (CdS) layer, which acts as a window layer. Fig. /CrossmarkMajorVersionDate (2010-04-23) The absorber layer is made from direct band gap CdTe TFs. number Note: Publication name can be used to differentiate between a print magazine and the online version if the names are different such as “magazine” and “magazine.com.” Geetam Richhariya, ... Samsher, in Photovoltaic Solar Energy Conversion, 2020. 10. Figure 18.1. The common identifier for all versions and renditions of a document. The conductivity type of CdTe can be controlled by the partial vapor pressure of the constituent element such as “Te”-rich contributes to p-type conductivity and “Cd”-rich results in n-type conductivity. /DR << 2 0 obj Nowshad Amin, ... M.D. Third, 40–200 nm thick Au layers were deposited as back contacts for solar cell performance evaluation. Text 8 0 obj /Pages 8 0 R noindex endobj endobj Paul Breeze, in Solar Power Generation, 2016. application/pdf Fig. CdTe thin film solar cell structure comprises of a p-type CdTe absorber layer and n-type CdS based window layer forming a heterojunction, which has an intermixed interface region. Mirrors crossmark:CrosMarkDomains In production facilities workers may be exposed to Cd compounds through the air they breathe, as well as by ingestion from hand-to-mouth contact. The introduction of a nanopatterned structure and CdS quantum dots in the n-i-p structure amorphous silicon solar cells enhances the photovoltaic properties. pdfx /Length 24847 effects of ITO layers of various thicknesses on the performance of CdS/CdTe solar cells are also studied. >> Based on AM1.5 6 0 obj 44.17 shows the top view SEM image of the CZTS thin film showing well-defined crystallites with small grain sizes of an average less than 0.5 µm, and the cross-sectional SEM view of CZTS layer deposited on Mo-coated SLG substrate showing also the regularly shaped and dense crystallites formed on the top of the Mo layer. 2015-05-20T12:39:58+05:30 The bulk CdTe has the cubic zinc blende structure. Among them, Cadmium Telluride (CdTe) has become a proven TFSCs material due to high potentiality in several of its merits. Comparing the rate of increase in perovskite solar cell efficiencies with the other thin-film PV technologies [19]. >> 2.2. Company creating the PDF Workers’ exposure to cadmium in PV manufacturing facilities is controlled by rigorous industrial hygiene practices and is continuously monitored by medical tests, thus preventing health risks [16,17]. Then a layer of p-type CdTe is added. Since CdTe has high absorption coefficient, thicknesses for CdTe thin films are limited within 2–10 μm (Albright et al., 1998). Note: PRISM recommends against the use of the #other value currently allowed in this controlled vocabulary. /PDFDocEncoding 10 0 R The maximum theoretical efficiency of CdTe solar cell corresponding to a bandgap of 1.5 eV is about 28%–30%. springer.com This accounts for the excellent material stability and device performance. MajorVersionDate /Last 14 0 R Text http://ns.adobe.com/xap/1.0/mm/ studied the crystallization of CZTS from coelectroplated Cu–Zn–Sn precursors using angle-dispersive X-ray measurements. Ending page Its efficiency is low compared to the crystalline material, but it is much cheaper to manufacture and it continues to command a share of the thin film market, particularly for small solar cells for electronic devices. 2010-04-23 doi Text Fig. Text Our work also includes advanced characterization, device modeling, and collaboration with university and industry partners. • Zincblend structure • Direct energy gap 1.44 eV • Can be growth both p-type (VCd acceptors) or n-type (Cd i donors) • me = 0.1 m0 • µe = 1100 cm2/Vs in single crystals • Difficult extrinsic doping • ηth = 31% Source: Wikipedia. Ever since CdTe solar modules have reached a production cost below USD 0.50 with an energy payback period of roughly 1 year as system along with 25 years warranty on power output, it is now cost competitive with main stream silicon-based solar PV technologies. 44.18. Fig. High mobility is important because, together with high charge carrier lifetimes, it means that the light-generated electrons and holes can move large enough distances to be extracted as current, instead of losing their energy as heat within the cell [19]. While the “substrate” configuration can be grown on any type of substrates that could be rigid glass or flexible metal or polymer foil. /BaseFont /ZapfDingbats Tom Baines, ... Jonathan D. Major, in A Comprehensive Guide to Solar Energy Systems, 2018. Text ��w�G� xR^���[�oƜch�g�`>b���$���*~� �:����E���b��~���,m,�-��ݖ,�Y��¬�*�6X�[ݱF�=�3�뭷Y��~dó ���t���i�z�f�6�~`{�v���.�Ng����#{�}�}��������j������c1X6���fm���;'_9 �r�:�8�q�:��˜�O:ϸ8������u��Jq���nv=���M����m����R 4 � internal CZTS, Cu2ZnSnS4. /Type /Font Figure 10.1. CdTe appears to be particularly effective for large area solar cells; this is its main strength. 9.3. The occupational health hazards presented by Cd and Te compounds in various processing steps vary as a function of the compound specific toxicity, its physical state, and the mode of exposure. CdTe has been shown to be the most promising polycrystalline thin film material for producing PV solar cells because of its high absorption coefficient (α > 10 4 cm −1) and optimum band gap (1.5 eV). No public health issues have been identified with this technology as toxic compounds cannot cause any adverse health effects unless they are dispersed into the environment. /Encoding << converted 2015-05-20T12:39:58+05:30 Hervé J. Tchognia Nkuissi, Bouchaib Hartiti, in Handbook of Nanomaterials for Industrial Applications, 2018. converted to PDF/A-2b /Subtype /Type1 /Name /Helv Senthilarasu Sundaram, ... Hari Upadhyaya, in A Comprehensive Guide to Solar Energy Systems, 2018. 2y�.-;!���K�Z� ���^�i�"L��0���-�� @8(��r�;q��7�L��y��&�Q��q�4�j���|�9�� << From Shockley Queisser diagram, CdTe with a band gap of 1.45eV has the potential to yield a theoretical high efficiency. >> /Count 10 It bears a reverse, n-i-p, configuration and the light enters through the last grown p-layer. /DA (/Helv 0 Tf 0 g ) However, the stability of CdTe solar cells is a complex problem which depends to a great degree on cell structure. In lieu of using #other please reach out to the PRISM group at [email protected] to request addition of your term to the Aggregation Type Controlled Vocabulary. issn /degree /plusminus /twosuperior /threesuperior /acute /mu 183 /periodcentered /cedilla /onesuperior copyright /Creator (Springer) /Dest (Title) Results indicate the electrical and optical parameters of CdTe/CdS solar cell with a … The date when a publication was publishe. They sequentially deposited metal layers of Cu, Sn, and Zn on Mo-coated SLG substrates at room temperature without stirring. external However, to improve the electrical properties of CdTe thin films, doping is usually utilized with dopants such as copper (Cu) or zinc (Zn) to lessen the resistivity and to improve the carrier concentration preferred for solar cell application. The usual architecture (Fig. 8 illustrates that the energy gap of CdTe is around 1.45 eV, which is in principle well suited to solar energy conversion. CdTe TF solar cells are grown on rigid and flexible substrates. The first synthesis of CZTS using electrochemical deposition was done by Scragg et al. x LIST OF FIGURES Figure Page 1-1. And between the two electrodes, cadmium sulfide is placed. Schurr et al. A novel structure of ultrathin CdTe solar cells is proposed in this paper that focuses on conversion efficiency. 5 0 obj The acute health effects from inhalation of Cd include pneumonitis, pulmonary edema, and death and such effects are also associated with soluble cadmium compounds like CdCl2. Perovskite solar cells stem from dye-sensitized solar cells but have promising solid state structures as well as rapid efficiency leaps (Fig. 1. /Subtype /XML sputtering. << All CZTS samples were found to be Cu-poor, nevertheless a KCN etching step was carried out to remove any CuxS phase from the CZTS surface before the CdS buffer layer deposition. /acircumflex /atilde /adieresis /aring /ae /ccedilla /egrave /eacute /ecircumflex /edieresis Flux to the disposal of manufacturing waste and end-of-life modules ; these are in. Poor adhesion of the # other value allowed in this paper that focuses on conversion.... 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