Chemical bath process for highly efficient Cd-free chalcopyrite thin-film-based solar cells

The highest efficiency for Cu(Ga,In)Se2 (CIGS) thin-film-based solar cells has been achieved with CdS buffer layers prepared by a solution growth method known as the chemical bath deposition (CBD). With the aim of developing Cd-free chalcopyrite-based thin-film solar cells, we describe the basic concepts involved in the CBD technique. The recipes developed in our laboratory for the heterogeneous deposition of good-quality thin films of ZnO, ZnSe, and MnS are presented. In view of device optimization, the initial formation of chemical-bath-deposited ZnSe thin films on Cu(Ga,In)(S,Se)2 (CIGSS) and the subsequent development of the ZnSe/CIGSS heterojunctions were investigated by X-ray photoelectron spectroscopy (XPS). The good surface coverage was controlled by measuring changes in the valence-band electronic structure as well as changes in the In4d, Zn3d core lines. From these measurements, the growth rate was found to be around 3.6 nm/min. The valence band and the conduction band-offsets ΔEV and ΔEC between the layers were determined to be 0.60 and 1.27 eV, respectively for the CIGSS/ZnSe interface. The energy-band diagram is discussed in connection with the band-offsets detemined from XPS data. A ZnSe thickness below 10 nm has been found to be optimum for achieving a homogeneous and compact buffer layer on CIGSS with a total area efficiency of 13.7%.PACS No.: 42.70

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Zinc Sulfide Nanoscaled Buffer Layers for Cu(In,Ga)Se2 Thin Film Solar Cells by Chemical Bath Deposition

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.51.125 ◽

2008 ◽

Vol 51 ◽

pp. 125-130 ◽

Cited By ~ 5

Author(s):

Rong Fuh Louh ◽

Warren Wu

Keyword(s):

Thin Film ◽

Thin Films ◽

Solar Cells ◽

Zinc Sulfide ◽

Chemical Bath Deposition ◽

Energy Gap ◽

Buffer Layers ◽

Thin Film Solar Cells ◽

Complexing Agents ◽

Study Results

Chemical bath deposition (CBD) is a fairly simple synthetic route to prepare II-VI semicondutive zinc sulfide thin films, which can be prepared on the flat surface of glass or silicon wafer substrates in the solution containing the precursors of zinc and sulfur ions in terms of ambient conditions of varying acidity. This study particularly aims at the growth dependence and optical property of ZnS thin films in the CBD process by different experiment parameters, whereas we intend to choose suitable types of zinc ionic precursors to be coupled with various CBD parameters such as reaction temperature and time, precursor concentration, types and complexing agents as well as post-deposition heat treatment conditions. Addition of different concentration of ethylenediamine, ammonium sulfate, sodium citrate and hydrazine in the CBD reaction process was used to control the adequate growth rate of ZnS thin films. As a consequence, the rapid thermal annealing was employed to enhance the film uniformity and thickness evenness, transmittance and the energy gap of ZnS samples. The results would lead to a potential application of buffer layer for the Cu (In,Ga)Se2 based thin film solar cells. The analytic instrument including SEM, AFM, UV-VIS were used to examine the CBD-derived nanosized ZnS buffer layers for the thin film solar cells. The ZnS thin films prepared by the chemical bath deposition in this study results in film thickness of 80 ~ 100 nm, high transmittance of 80~85% and the energy gap of 3.89 ~ 3.98 eV.

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Fabrication of Zn(O,S) thin films by ozone assisted photochemical deposition and its potential applications as buffer layers in kesterite-based thin film solar cells

Thin Solid Films ◽

10.1016/j.tsf.2018.12.002 ◽

2019 ◽

Vol 670 ◽

pp. 80-85 ◽

Cited By ~ 4

Author(s):

Jun Zhang ◽

Jingjie Feng ◽

Ye Feng ◽

Jun Liao ◽

Shuwen Xue ◽

...

Keyword(s):

Thin Film ◽

Thin Films ◽

Solar Cells ◽

Buffer Layers ◽

Thin Film Solar Cells ◽

Photochemical Deposition ◽

Potential Applications

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7.1% efficient co-electroplated Cu2ZnSnS4 thin film solar cells with sputtered CdS buffer layers

Green Chemistry ◽

10.1039/c5gc02057c ◽

2016 ◽

Vol 18 (2) ◽

pp. 550-557 ◽

Cited By ~ 81

Author(s):

Jiahua Tao ◽

Junfeng Liu ◽

Leilei Chen ◽

Huiyi Cao ◽

Xiankuan Meng ◽

...

Keyword(s):

Thin Film ◽

Thin Films ◽

Solar Cells ◽

Buffer Layers ◽

Thin Film Solar Cells ◽

Pure Phase ◽

Fine Control ◽

Cu2znsns4 Thin Film ◽

Czts Thin Films

Cu2ZnSnS4 (CZTS) thin films with fine control over composition and pure phase were fabricated by sulfurization of co-electroplated Cu–Zn–Sn–S precursors.

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X-ray Photoelectron Spectroscopy Analysis of Chitosan–Graphene Oxide-Based Composite Thin Films for Potential Optical Sensing Applications

Polymers ◽

10.3390/polym13030478 ◽

2021 ◽

Vol 13 (3) ◽

pp. 478

Author(s):

Wan Mohd Ebtisyam Mustaqim Mohd Daniyal ◽

Yap Wing Fen ◽

Silvan Saleviter ◽

Narong Chanlek ◽

Hideki Nakajima ◽

...

Keyword(s):

Thin Film ◽

Thin Films ◽

Graphene Oxide ◽

Photoelectron Spectroscopy ◽

Functional Group ◽

Optical Sensing ◽

Composite Thin Films ◽

Cobalt Ions ◽

X Ray ◽

Sensing Applications

In this study, X-ray photoelectron spectroscopy (XPS) was used to study chitosan–graphene oxide (chitosan–GO) incorporated with 4-(2-pyridylazo)resorcinol (PAR) and cadmium sulfide quantum dot (CdS QD) composite thin films for the potential optical sensing of cobalt ions (Co2+). From the XPS results, it was confirmed that carbon, oxygen, and nitrogen elements existed on the PAR–chitosan–GO thin film, while for CdS QD–chitosan–GO, the existence of carbon, oxygen, cadmium, nitrogen, and sulfur were confirmed. Further deconvolution of each element using the Gaussian–Lorentzian curve fitting program revealed the sub-peak component of each element and hence the corresponding functional group was identified. Next, investigation using surface plasmon resonance (SPR) optical sensor proved that both chitosan–GO-based thin films were able to detect Co2+ as low as 0.01 ppm for both composite thin films, while the PAR had the higher binding affinity. The interaction of the Co2+ with the thin films was characterized again using XPS to confirm the functional group involved during the reaction. The XPS results proved that primary amino in the PAR–chitosan–GO thin film contributed more important role for the reaction with Co2+, as in agreement with the SPR results.

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Thin film bi-epitaxy and transition characteristics of TiO2/TiN buffered VO2 on Si(100) substrates

MRS Advances ◽

10.1557/adv.2016.544 ◽

2016 ◽

Vol 1 (37) ◽

pp. 2635-2640 ◽

Cited By ~ 5

Author(s):

Adele Moatti ◽

Reza Bayati ◽

Srinivasa Rao Singamaneni ◽

Jagdish Narayan

Keyword(s):

Thin Film ◽

Thin Films ◽

Magnetic Properties ◽

Frequency Factor ◽

Misfit Strain ◽

Buffer Layers ◽

Intrinsic Defects ◽

Domain Matching Epitaxy ◽

Out Of Plane

ABSTRACTBi-epitaxial VO2 thin films with [011] out-of-plane orientation were integrated with Si(100) substrates through TiO2/TiN buffer layers. At the first step, TiN is grown epitaxially on Si(100), where a cube-on-cube epitaxy is achieved. Then, TiN was oxidized in-situ ending up having epitaxial r-TiO2. Finally, VO2 was deposited on top of TiO2. The alignment across the interfaces was stablished as VO2(011)║TiO2(110)║TiN(100)║Si(100) and VO2(110) /VO2(010)║TiO2(011)║TiN(112)║Si(112). The inter-planar spacing of VO2(010) and TiO2(011) equal to 2.26 and 2.50 Å, respectively. This results in a 9.78% tensile misfit strain in VO2(010) lattice which relaxes through 9/10 alteration domains with a frequency factor of 0.5, according to the domain matching epitaxy paradigm. Also, the inter-planar spacing of VO2(011) and TiO2(011) equals to 3.19 and 2.50 Å, respectively. This results in a 27.6% compressive misfit strain in VO2(011) lattice which relaxes through 3/4 alteration domains with a frequency factor of 0.57. We studied semiconductor to metal transition characteristics of VO2/TiO2/TiN/Si heterostructures and established a correlation between intrinsic defects and magnetic properties.

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CdTe Thin Film Solar Cells: The CdS/SnO2 Front Contact

MRS Proceedings ◽

10.1557/proc-668-h5.1 ◽

2001 ◽

Vol 668 ◽

Cited By ~ 9

Author(s):

J. Fritsche ◽

S. Gunst ◽

A. Thiβen ◽

R. Gegenwart ◽

A. Klein ◽

...

Keyword(s):

Thin Film ◽

Solar Cells ◽

Band Gap ◽

Photoelectron Spectroscopy ◽

Tin Dioxide ◽

Surface Preparation ◽

Thin Film Solar Cells ◽

Subsequent Formation ◽

Coated Glass ◽

Preparation Conditions

ABSTRACTTin dioxide (SnO2) coated glass is the commonly used substrate for thin film solar cells based on CdTe absorbers. We have investigated the properties of the CdS/SnO2 interface by X-ray and ultraviolet photoelectron spectroscopy. SnO2 coated glass substrates as used for solar cell preparation were cleaned by different procedures such as derinsing, sputtering, heating and annealing in oxygen atmosphere. Different surface properties with a strongly dependent number of defects in the SnO2 band gap are identified. CdS films were deposited stepwise by thermal evaporation to determine the electronic interface properties for different surface preparation conditions. Comparative barrier heights at the CdSSnO2 contact are found for most surface pretreatments. The Fermi level position in these cases is situated in the SnO2 band gap. A different interface behaviour is determined for sputter cleaned SnO2 surfaces, which is attributed to the formation of oxygen vacancies during sputtering and subsequent formation of an interfacial SnOxSy compound.

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Cu 2 Si x Sn 1− x S 3 Thin Films Prepared by Reactive Magnetron Sputtering For Low-Cost Thin Film Solar Cells

Chinese Physics Letters ◽

10.1088/0256-307x/28/10/108801 ◽

2011 ◽

Vol 28 (10) ◽

pp. 108801 ◽

Cited By ~ 4

Author(s):

Chang Yan ◽

Fang-Yang Liu ◽

Yan-Qing Lai ◽

Jie Li ◽

Ye-Xiang Liu

Keyword(s):

Thin Film ◽

Thin Films ◽

Solar Cells ◽

Magnetron Sputtering ◽

Low Cost ◽

Reactive Magnetron Sputtering ◽

Thin Film Solar Cells ◽

Reactive Magnetron

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Improving the stabilities of organic solar cells via employing a mixed cathode buffer layer

The European Physical Journal Applied Physics ◽

10.1051/epjap/2021210151 ◽

2021 ◽

Vol 95 (3) ◽

pp. 30201

Author(s):

Xi Guan ◽

Yufei Wang ◽

Shang Feng ◽

Jidong Zhang ◽

Qingqing Yang ◽

...

Keyword(s):

Thin Film ◽

Thermal Stability ◽

Solar Cells ◽

Mixed Layer ◽

Organic Solar Cells ◽

Buffer Layers ◽

Commercial Development ◽

Conversion Efficiencies ◽

Thermal Stability Of ◽

Cathode Buffer Layers

Organic solar cells (OSCs) have been fabricated using cathode buffer layers based on bathocuproine (BCP) and 4,4'-N,N'-dicarbazole-biphenyl (CBP). It is found that despite nearly same power conversion efficiencies, the bilayer of BCP/CBP shows increased thermal stability of device than the monolayer of BCP, mostly because upper CBP thin film stabilizes under BCP thin film. The mixed layer of BCP:CBP gives slightly decreased efficiency than BCP and BCP/CBP, mostly because the electron mobility of the OSC using BCP:CBP is decreased than those using BCP and BCP/CBP. However, the BCP:CBP increases thermal stability of device than BCP and BCP/CBP, ascribed to that the BCP and CBP effectively inhibit reciprocal tendencies of crystallizations in the mixed layer. Moreover, the BCP:CBP improves the light stability of device than the BCP and BCP/CBP, because the energy transfer from BCP to CBP in in the mixed layer effectively decelerates the photodegradation of BCP. We provide a facial method to improve the stabilities of cathode buffer layers against heat and light, beneficial to the commercial development of OSCs.

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