cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Emergent non-Hermitian localization phenomena in the synthetic space of zero-dimensional bosonic systems
Creators: name: Arkhipov, Ievgen I.
name: Minganti, Fabrizio
Publisher: name: arXiv
Year: 2021
Subjects: subject: Quantum Physics (quant-ph)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: Phase transitions in non-Hermitian systems are at the focus of cutting edge theoretical and experimental research. On the one hand, parity-time- ($\cal PT$-) and anti-$\cal PT$-symmetric physics have gained ever-growing interest, due to the existence of non-Hermitian spectral singularities called exceptional points (EPs). On the other, topological and localization transitions in non-Hermitian systems reveal new phenomena, e.g., the non-Hermitian skin effect and the absence of conventional bulk-boundary correspondence. The great majority of previous studies exclusively focus on non-Hermitian Hamiltonians, whose realization requires an {\it a priori} fine-tuned extended lattices to exhibit topological and localization transition phenomena.In this work, we show how the non-Hermitian localization phenomena can naturally emerge in the synthetic field moments space of zero-dimensional bosonic systems, e.g., in anti-$\cal PT$ and $\cal PT$-symmetric quantum dimers. This offers an opportunity to simulate localization transitions in low-dimensional systems, without the need to construct complex arrays of, e.g., coupled cavities or waveguides. Indeed, the field moment equations of motion can describe an equivalent (quasi-)particle moving in a one-dimensional (1D) synthetic lattice. This synthetic field moments space can exhibit a nontrivial localization phenomena, such as non-Hermitian skin effect, induced by the presence of highly-degenerate EPs. We demonstrate our findings on the example of an anti-$\cal PT$-symmetric two-mode system, whose higher-order field moments eigenspace is emulated by a synthetic 1D non-Hermitian Hamiltonian having a Sylvester matrix shape. Our results can be directly verified in state-of-the-art optical setups, such as superconducting circuits and toroidal resonators, by measuring photon moments or correlation functions.
description: 18 pages
Electrode Influence on Bi-Layer Bulk Heterojunction Solar Cell Containing P3HT
Creators: name: Kaulacs, I.
name: Muzikante, I.
name: Gerca, L.
name: Shlihta, G.
name: Shipkovs, P.
name: Kashkarova, G.
name: Roze, M.
name: Kalnachs, J.
name: Murashov, A.
name: Latvels, J.
name: Rozite, G.
Publisher: name: WIP
Year: 2011
Subjects: Advanced Photovoltaics : New Concepts and Ultra-High Efficiency
Organic-based PV

description: 26th European Photovoltaic Solar Energy Conference and Exhibition; 601-604
description: The main aim of the present work is to extend the spectral range of a well-known bulk heterojunction
solar cell of poly-3-hexylthiophene (P3HT) and a soluble fullerene derivative (PCBM) up to 850 nm by adding a
second bulk heterojunction layer of the complementary absorption spectrum to the P3HT:PCBM layer. Therefore a
hydroxygallium phthalocyanine (GaOHPc) and PCBM blend was used as an additional layer because GaOHPc has a
strong and wide intermolecular charge transfer (CT) absorption band of around 830-850 nm. Thus a novel organic bilayer
bulk heterojunction system (GaOHPc:PCBM/P3HT:PCBM) having high charge carrier photogeneration
efficiency in the 350 – 850 nm spectral range has been built by spin-coating technique. It was found that thermal
annealing in vacuum at 100OC increases short-circuit photocurrent external quantum efficiency (EQE) values more
than 2 times. Different top electrodes of Al, In, Sm/Al and Yb/Al/Se were examined to achieve the best performance
of our bi-layer cell. It was found that the best power conversion efficiency (PCE) is provided by a Yb/Al electrode
covered with a protective Se layer.
Characterising PV Modules Under Outdoor Conditions: What’s Most Important for Energy Yield
Creators: name: Sutterlueti, J.
name: Ransome, S.
name: Kravets, R.
name: Schreier, L.
Publisher: name: WIP
Year: 2011
Subjects: Components for PV Systems
PV Modules

description: 26th European Photovoltaic Solar Energy Conference and Exhibition; 3608-3614
description: Standard parameters in Photovoltaic (PV) such as Final Energy Yield (YF) or Performance Ratio (PR) (IEC
61724) are simply calculated as sums (YF) or averages (PR) of the PV device performance over the measurement
period and therefore do not allow for correlations with parameters such as irradiance, temperature or downtime.
For a better characterisation and prediction of PV module performance under outdoor conditions detailed
studies on the level of I-V parameters would be desirable. However, algorithms as used in commercial simulation
programs were found to be of limited use [1].
Therefore a new “Loss factors model” (LFM) has been developed which determines a module’s performance
from its I-V curve simply as the product of five physically significant and independent normalized “loss factors” as
well as spectral and temperature corrections. The benefits of such a Loss Factors Model will be shown in this paper.
It allows validation of technology improvements, also performance distributions in mass production can be checked
by quantifying initial losses and separating them from any long term changes. It also benchmarks different modules,
production series or technologies at sites with different climates and can be used for Energy yield and Performance
predictions. Differences at low light behaviour and temperature coefficients can be checked and validated with the
LFM and seasonal changes can be distinguished from module degradation. Previously, the effect of energy yield
losses due to RSC and ROC were hard to quantify, now they can be determined easily and the value of improvements
can be estimated.
In the present paper the LFM has been verified for different PV module technologies (c-Si, HIT, a-Si, CIGS,
CdTe and a-Si/uc-Si) in two different climatic conditions (Switzerland and Arizona)[3]. Good fits to module
performance (ISC, RSC, FF, ROC and VOC and hence PMAX or efficiency) were obtained under a wide variety of weather
conditions.
Long Term Performance Variation of Amorphous Silicon Solar Cells due to Different Operating Temperatures
Creators: name: Astawa, K.S.
name: Betts, T.R.
name: Gottschalg, R.
Publisher: name: WIP-Munich
Year: 2009
Subjects: Thin Films Solar Cells
Amorphous and Microcrystalline Silicon Solar Cells

description: 24th European Photovoltaic Solar Energy Conference, 21-25 September 2009, Hamburg, Germany; 2731-2734
description: A perceived disadvantage of amorphous silicon solar cells is their light-induced degradation or so called
‘Staebler-Wronski’ effect (SWE) which is different in different locations. This paper investigates the influence of
different thermal regimes on the degradation of various samples (single, double and triple junction) in outdoor
operation. A dedicated measurement system has been developed consisting of a back-ventilated, back-insulated and a
heated installation. The modules are characterised repeatedly in a Spire flash solar simulator. The efficiency degrades
by 12 to 27 % in the first two weeks after installation and continues to decrease for the first year. Further losses are 2
to 7% in the first 6 months of exposure, before degraded another 1 – 2% for the closing state of equilibrium in the
first year monitoring. The degradation of the first twelve months always shows that the heated devices have the
lowest degradation and the back ventilated ones have the highest one, with the back insulated ones being somewhere
in the middle (virtually identical to the back ventilated one in the case of the single junctions and close to the heated
ones for the triple junction)
Stacks of a-SiCx Layers on Planar and Textured Surfaces for the Solar Cell Front Side on Both n+- and p+-Emitters
Creators: name: Steinhauser, B.
name: Suwito, D.
name: Janz, S.
name: Hermle, M.
Publisher: name: WIP-Munich
Year: 2010
Subjects: Wafer-Based Silicon Solar Cells and Materials Technology
Mono- and Multicrystalline Silicon Materials and Cells

description: 25th European Photovoltaic Solar Energy Conference and Exhibition / 5th World Conference on Photovoltaic Energy Conversion, 6-10 September 2010, Valencia, Spain; 2250-2254
description: In this work we present stacks of a-SiCx:H layers for the solar cell front side on highly doped surfaces.
The focus is set on single and double layer stacks which effectively reduce the surface recombination of phosphorus
emitters. On planer surfaces emitter saturation current densities of J0e < 20 fA/cm2 have been found for stacks
combining an intrinsic with a doped passivation layer. A major drawback has been observed when using these
passivation stack systems deposited by high-frequency (HF) plasma-enhanced chemical vapor deposition (PECVD)
on textured surfaces – the J0e values increase by a factor of 8-10 compared to results obtained on planar surfaces.
This issue has been explained by developing a model for the field in the HF plasma near the textured surface and by
discussing its influence on the plasma particles and thus on the local composition of the passivation layers. One way
to avoid these field effects is to use a microwave (MW) plasma source. Therefore MW-deposited passivation layers
have equally been evaluated on planar and textured surfaces. The results are compared to the results of the HFdeposited
passivation stacks and the differences are discussed. In addition, the performance of the a-SiCx emitter
passivation at solar cell level is investigated. Furthermore, an anti-reflection coating (ARC) by C-rich amorphous
silicon carbide is presented and compared to a state-of-the-art SiNx ARC.
Investigations of Material Parameters and Device Stability in Polymer:Fullerene Solar Cells Using Impedance Spectroscopy
Creators: name: Ecker, B.
name: Parisi, J.
name: Von Hauff, E.
Publisher: name: WIP
Year: 2011
Subjects: Advanced Photovoltaics : New Concepts and Ultra-High Efficiency
Organic-based PV

description: 26th European Photovoltaic Solar Energy Conference and Exhibition; 595-596
description: We demonstrate that impedance spectroscopy (IS) is a powerful tool to determine material properties
and understand device operation and stability in polymer:fullerene solar cells. IS gives direct access to the frequency
and voltage dependent dielectric behavior of the individual layers and interfaces as well as the complete device. In the
first part of the paper we present IS results on poly(3-hexylthiophene) (P3HT) diodes. In the second part of the paper
we present results on IS investigations of P3HT:[6,6]-phenyl-C61-butyric acid methyl ester (PCBM) solar cells. Lastly
we show how impedance spectroscopy can be used to investigate degradation-related changes to layers and interfaces
in the solar cell.
Surface Soiling Losses Measurement in PV Modules under Real Operation
Creators: name: Martín Chivelet, N.
name: Chenlo, F.
name: Alonso-García, M.C.
name: Ariza, M.A.
name: Mejuto, E.
name: Angulo, M.
name: Neumann, D.
name: Prast, M.-O.
name: Mazón, P.
Publisher: name: WIP
Year: 2011
Subjects: Components for PV Systems
PV Modules

description: 26th European Photovoltaic Solar Energy Conference and Exhibition; 3597-3599
description: The purpose of this work is to quantify the effect of PV modules’ surface soiling losses on the energy
rating of PV plants and buildings, considering different PV cover glasses, tilt angles and cleaning regimes. The study
contemplates the influence that the PV module’s front cover characteristics have on the soiling retention, as well as
the convenience or not to adopt a periodic cleaning maintenance. For that purpose the photogenerated currents of 48
PV modules having four different types of cover glasses have been monitorized and compared, together with
irradiation and temperature data. The modules are installed on two South oriented fixed structures, tilted 10 and 40
degrees respectively, sited at Ciemat facilities, in Madrid. Half of all of them have been cleaned every three months,
and the rest have not been cleaned at all. The four different types of cover glasses are manufactured by company
Saint-Gobain and also module production was made in Saint-Gobain R&D facility in Germany.
Spectral Dependent Annual Yield of Different Photovoltaic Technologies
Creators: name: Zinsser, B.
name: Schubert, M.B.
name: Werner, J.H.
Publisher: name: WIP
Year: 2011
Subjects: Components for PV Systems
PV Modules

description: 26th European Photovoltaic Solar Energy Conference and Exhibition; 3615-3618
description: For each fifteen minute interval of one year, the solar irradiance was measured in Stuttgart, Germany. The measurement
was performed not only via pyranometer, but also with a spectroradiometer to get the spectral power for each wavelength
in the range 300 to 1600 nm. The analysis of the spectrum shows that the yearly average is a little bit “bluer” than the
standard solar spectrum AM1.5g. Calculating the convolution integral of measured spectrum and quantum efficiency
yields the short circuit current for different photovoltaic (PV) technologies, namely crystalline silicon and three thin film
technologies. The analysis to quantify the spectral effect on the annual energy yield of different PV technologies shows
that resulting differences are smaller than one percent.
Graphene Based Schottky Barrier Solar Cells
Creators: name: Lancellotti, L.
name: Polichetti, T.
name: Ricciardella, F
name: Tari, O.
name: Guerriero, P.
name: Gnanapragasam, S.
name: Nasti, I.
name: Di Francia, G.
Publisher: name: WIP
Year: 2011
Subjects: Advanced Photovoltaics : New Concepts and Ultra-High Efficiency
Organic-based PV

description: 26th European Photovoltaic Solar Energy Conference and Exhibition; 533-537
description: The experimental isolation of graphene by micromechanical cleavage of highly oriented pyrolytic graphite
(HOPG) has stimulated much experimental and theoretical research. In the last few years, a great deal of work has been
dedicated to test how the theoretical predictions match the experimentally determined properties of graphene.
Recent works have shown that graphene sheets (GS) deposited on n-type Si wafer to give Schottky barrier solar cells
(SBSC) allow to achieve efficiencies up to 1.5%.
Our paper reports a study about the final performances of graphene-on-semiconductor Schottky junction solar cells
showing the potentiality of this kind of device. A generalized equivalent circuit model of graphene based SBSC is
presented to simulate the device behavior: the circuital parameters used in the model are strictly dependent on the
physical properties of the GS and of the semiconductor which form the Schottky junction. Electrical Capacitance-
Voltage (CV) characterization performed on some “ad hoc” realized structures, have been used to obtain the
experimental value of some important physical parameters used in the calculations.
Classifying Crime Rates in Highly Urbanized Regions through Generic Mapping in a Modern Setting
Creators: name: Isiaka, Fatima
name: Zainab, Adamu
Publisher: name: International Journal of Computer Aided Design and Application
Year: 2023

description: The use of Generic mapping is a wide range of processes used across earth studies on different investigations of different activities and actions that also include locations on planetary, ocean sciences, and beyond. A largecommunity of research processes in Geo-mapping used generic mapping to process data and also to generate publication-based quantitative illustrations that automate workflows and design animations for researchpurposes. One of the major areas of study in which generic mapping is most important is the area of crime rates and its studies, especially in a largely urbanised area like the United States. The paper looks intothe fundamentals in the study of crime rate and the process of depicting the class of crime through generic mapping with R language. The basics and importance of identifying crime rates and location are discussedand the result section shows some of the outputs derived from generic classification mapping.
Performance Comparison of Three Technology Modules under Similar Outdoor Conditions
Creators: name: Sastry, O.S.
name: Kumar, A.
name: Singh, R.K.
name: Adiraju, D.
name: Anand, A.
name: Kumar, R.
name: Bandyopadhyay, B.
Publisher: name: WIP
Year: 2011
Subjects: Components for PV Systems
PV Modules

description: 26th European Photovoltaic Solar Energy Conference and Exhibition; 3566-3568
description: Among the major applications of solar photovoltaics, Grid Interactive (GI) operation has maximum energy
conversion efficiencies, easy to install & operate and offers faster paybacks. GI system’s performance is rated based on
performance indicators like energy yields (daily, monthly & yearly) and Performance Ratio (PR). While the energy yields
depends on intensity of sun radiation & temperature, the PR values are independent of sun radiation and PV array size, and
solely dependent on the ambient temperature, Spectral Response(SR) of solar cells and sun spectrum distribution at site and
time. Hence, PR values are site specific and technology dependent. For this reason it is imperative to identify site specific
PV technologies those offer maximum yields based on PR values. Ministry of New and Renewable Energy (MNRE),
Government of India initiated one of the world’s most ambitious Jawaharlal Nehru National Solar Mission (JNNSM)
programme targeting to establish 20GWp capacity of solar power plants in the country by 2020. The proposed studies by
Solar Energy Centre (SEC) are in conjunction with MNRE programme and an initial step towards preparation of PR rating
maps for the country. This paper presents SEC’s studies on PR values for three PV technology modules through outdoor test
beds.
Performance Parameters for Hydrogenated Amorphous Silicon PV Modules under Different Weather Conditions
Creators: name: Roldán, R.
name: Asensi, J.M.
name: Bertomeu, J.
name: Andreu, J.
Publisher: name: WIP
Year: 2011
Subjects: Components for PV Systems
PV Modules

description: 26th European Photovoltaic Solar Energy Conference and Exhibition; 3581-3584
description: An analytical model is employed for the simulation of the annual energy production for a hydrogenated
amorphous silicon photovoltaic module. The methodology employed to determine the value of the model
parameters considers laboratory device characterization and outdoor measurements. The accuracy in the
efficiency prediction behaves seasonally. It decreases during the warmer months, mainly in summer, due to the
spectral and thermal annealing effect which is not properly considered in the model. The annual variation of most
significant relative errors (based on monthly average) highlights their influence on the seasonal variation of the
accuracy in energy prediction. Careful selection of the clear sky days allows an accuracy of 6.9% in monthly basis and 2.6% in annual basis.
Additives for Improved Texturisation of mc-Si Solar Cells
Creators: name: Braun, S.
name: Mathijssen, S.
name: Lin, W.C.
name: Shen, M.M.
name: Michel, M.
name: Schmidt, M.
name: Klipp, A.
Publisher: name: WIP-Munich
Year: 2010
Subjects: Wafer-Based Silicon Solar Cells and Materials Technology
Mono- and Multicrystalline Silicon Materials and Cells

description: 25th European Photovoltaic Solar Energy Conference and Exhibition / 5th World Conference on Photovoltaic Energy Conversion, 6-10 September 2010, Valencia, Spain; 2199-2200
description: Using an improved texturisation it was possible to reduce the reflectivity of multi crystalline
wafers by about 6%. This improvement in reflectivity comes from a surface morphology with an improved depth
to width ratio of the structures. The improved reflectivity is still present after the anti-reflective coating, even
thus the absolute value is smaller (1.4%).
Behind 2.0: The Back Enhanced Heterostructure with Interdigitated Contact Solar Cell Evolution
Creators: name: Tucci, M.
name: De Iuliis, S.
name: Serenelli, L.
name: Izzi, M.
name: Salza, E.
name: De Luca, V.
name: Velardi, F.
name: Sanseverino, A.
name: De Cesare, G.
name: Caputo, D.
Publisher: name: WIP-Munich
Year: 2010
Subjects: Wafer-Based Silicon Solar Cells and Materials Technology
Mono- and Multicrystalline Silicon Materials and Cells

description: 25th European Photovoltaic Solar Energy Conference and Exhibition / 5th World Conference on Photovoltaic Energy Conversion, 6-10 September 2010, Valencia, Spain; 2089-2093
description: In this work we present the BEHIND 2.0 cell. The proposed back interdigitated amorphous/crystalline
silicon heterostructure fabrication process has been exploited and simplified. We have fabricated rear junction,
backside contact cells in which both the emitter and the back contact are formed by amorphous/crystalline silicon
heterostructure, and the grid-less front surface is passivated by a double layer of amorphous silicon and silicon
nitride, which also provides an anti-reflection coating. The entire self-aligned mask and photolithography-free
process is performed at temperature below 300 °C with the aid of two metallic masks to create the interdigitated
pattern, while the metallisation have been performed by screen-printing. We remark that the mask alignment is not
critical since the n-type a-Si:H emitter width is three times wider than the p-type a-Si:H region. Initial results and
modelling indicate that the intrinsic buffer layer plays a fundamental role in silicon surface passivation and isolation
between the two contacts to enhance the cell open circuit voltage. The optimum buffer layer thickness has been
evaluated to be 3.5 nm. Further the spacing between the two rear doped regions dramatically influences the
photogenerated carrier collection, namely the fill factor. The modelling indicates that the best width spacing should
shorter than 10 um. Finally the front surface passivation has been improved by particular SiNx films.
Phosphorous Dopant Surface Conformality: A Comparison Study of In-Line Spray Diffusion on Textured Si Wafers
Creators: name: Richter, P.J.
name: Peelamedu, R.
name: Bottari, F.J.
Publisher: name: WIP-Munich
Year: 2010
Subjects: Wafer-Based Silicon Solar Cells and Materials Technology
Mono- and Multicrystalline Silicon Materials and Cells

description: 25th European Photovoltaic Solar Energy Conference and Exhibition / 5th World Conference on Photovoltaic Energy Conversion, 6-10 September 2010, Valencia, Spain; 2207-2210
description: For inline diffusion, the surface conformality of spray-coated phosporic acid dopant solutions of
different formulations on textured Si wafers was measured and compared to POCl3 vapor deposition.
Topographic and microstructural characterization of coatings produced from organic and aqueous based
solutions was carried out by scanning electon microscopy. The phosphorus distribution on the surface of both
pre- and post-diffused wafers was analyzed by energy dispersive X-ray spectroscopy. For the spray diffused
wafers, a phosphorus distribution relationship was established between pre- and post-diffused wafers. The
formulations using isopropanol as the transport medium produced better coating conformality than aqueous
solutions.
Thin-Film Organic Solar Modules – Processing and Laser Ablation
Creators: name: González Moreno, J.
name: Bärenklau, M.
name: Schoonderbeek, A.
name: Muhsin, B.
name: Haupt, O.
name: Rösch, R.
name: Gobsch, G.
name: Teckhaus, D.
name: Hoppe, H.
name: Stute, U.
Publisher: name: WIP
Year: 2011
Subjects: Advanced Photovoltaics : New Concepts and Ultra-High Efficiency
Organic-based PV

description: 26th European Photovoltaic Solar Energy Conference and Exhibition; 538-542
description: The monolithic series connection of thin-film organic solar modules by means of laser structuring is
described in this paper. The main laser parameters for thin film processing are the radiation wavelength, pulse
duration, pulse energy and spot-spot overlap. The results obtained with the best suitable evaluated laser sources and
the processing parameters are optimized and presented in this paper. The focus of the experiments is to obtain an
optimal edge quality of the scribed line without damaging the substrate or the layer below the structured region. Test
modules on PET-foil substrate are produced using the optimized laser structuring process, resulting in a successful
series interconnection of the cells. The presented results show the applicability of the technology for future mass
production where processing speeds greater than 1 m/s are required. Currently available industrial laser sources are
able to achieve these processing speeds, necessary for economically feasible structuring of organic modules in a roll-to-
roll production.
Exciton Diffusion Length in MEH-PPV and CdS Nanoparticles Size Distribution by Surface Photovoltage Method
Creators: name: Touskova, J.
name: Tousek, J.
name: Remes, Z.
name: Polonskyi, O.
name: Kousal, J.
name: Rohovec, J.
name: Kuritka, I.
name: Schauer, F.
Publisher: name: WIP
Year: 2011
Subjects: Advanced Photovoltaics : New Concepts and Ultra-High Efficiency
Organic-based PV

description: 26th European Photovoltaic Solar Energy Conference and Exhibition; 554-558
description: The exciton diffusion length is a crucial parameter characterizing polymer materials for solar cells.
Method of surface photovoltage (SPV) used here for its evaluation is simple and quick. It utilizes an electric field at
surface of the sample for dissociation of photogenerated excitons, which can then lead to generation of the photocurrent
in an external circuit. In our case, such field is formed in the space charge region (SCR) at the ITO/polymer interface.
The advantage of our SPV model is possibility to apply it to samples with arbitrary ratio of thickness of the SCR and of
the bulk. The samples under study were MEH-PPV layers prepared by spin-coating technique using CHCl3 or THF
solvent. Ellipsometric measurement yielded data on thickness of the samples, absorption coefficients needed for
evaluation of SPV spectra were obtained from transmittance and reflectance measurements. Fitting of theory to
experiment yielded the exciton diffusion lengths (13-15 nm). CdS nanoparticles were synthesized by thermal
decomposition of cadmiumethylxanthate in triethanolamine or from cadmium chloride and ammonium thiosulfate
solutions. Sigma-Aldrich CdS nanocrystals were also studied. TEM and SPV techniques were applied to characterize the
size of the nanoparticles.
Using Cu-Doped TiO2 as Semiconductor in DSSCs
Creators: name: Navas, F.J.
name: Fernández-Lorenzo, C.
name: Aguilar, T.
name: Alcántara, R.
name: Martín-Calleja, J.
Publisher: name: WIP
Year: 2011
Subjects: Advanced Photovoltaics : New Concepts and Ultra-High Efficiency
Organic-based PV

description: 26th European Photovoltaic Solar Energy Conference and Exhibition; 572-575
description: TiO2 doping has been widely used in photocatalyis and photovoltaic cells to improve the performance
of this semiconductor. This paper studies the use of copper as a dopant in TiO2 in Dye Sensitized Solar Cells (DSSC),
analysing the effect on the photovoltaic properties of the cells of different concentrations of copper incorporated into
the semiconductor. The Cu-doped TiO2 semiconductor was characterized with several instrumental techniques,
including X-ray diffraction (XRD), inductively coupled plasma atomic emission spectroscopy (ICP-AES), and UVVis
spectroscopy in order to know its structure, composition and band gap energies with different concentrations of
the dopant. An analysis was also performed of the variations in open-circuit voltage depending on the concentration
of copper. This showed that the presence of copper in DSSCs made with a standard configuration - using a ruthenium
complex (N3) as a dye and the redox pair I-/I3
- as the electrolyte with 3-methoxypropionitrile as a solvent - leads to
improvements of up to 10% in the open-circuit voltage of DSSCs.
Development of a Novel Technique for Mechanical Characterization of Polymer Encapsulates in Laminated Glass Beams
Creators: name: Ehrich, C.
name: Schulze, S.-H.
name: Hinz, I.
name: Pander, M.
name: Ebert, M.
Publisher: name: WIP
Year: 2011
Subjects: Components for PV Systems
PV Modules

description: 26th European Photovoltaic Solar Energy Conference and Exhibition; 3560-3565
description: Since decades, Ethylene-vinylacetate (EVA) materials are used for embedding crystalline and thin film solar
cells. Because of their interesting processing properties, thermoplastic materials such as Polyvinyl-butyral (PVB) or
Thermoplastic Silicon Elastomers (TPSE) come more and more into focus. One of their disadvantages can be an increased
material creep under constant mechanical load or worse aging resistance than covalently cross linked EVA. When
encapsulate materials are tested regarding their aging behavior under controlled environmental conditions, they usually are
weathered in the PV-modules or as neat polymers. Although weathering of polymers in PV-modules comes close to real
conditions, sample taking for mechanical tests is nearly impossible. Weathering of neat polymer encapsulates can on the one
hand solve the problem of sample taking, but when they are not encapsulated between front and back glasses or backsheets,
the aging conditions are far away from reality. In this work we present a novel technique for the mechanical characterization
of encapsulate materials in an efficient and cost effective laboratory-scale procedure. First, laminated glass beams were
manufactured using EVA Etimex 496.10, PVB Trosifol R40 and TPSE Tectosil 177 encapsulate materials, which have
already been characterized in regard to their processing behavior in our last publications. These glass beams were weathered
using IEC 61215 procedure of damp-heat test, then taken out and tested via 3-point bending. Under 3-point bending, the
laminate stiffness in the elastic range and creep behavior under constant load were detected. A mechanical model on the base
of beam theories was developed to account for the influence of the interlayer on the laminate stiffness. Through this model,
we were able to numerically calculate the parameter responsible for the influence of the polymeric interlayer on laminate
stiffness, the shear modulus Gc of the interlayer, despite of varying thicknesses of the laminate beams with different
polymeric interlayers. The results show, that a trend in stiffness behaviour and polymer creep in regard to material aging can
be observed using amorphous materials. Additionally, implications on the load-deflection behaviour of modules under use of
the determined material changes are given using Finite-Element simulation.
Torsion Moment from Wind Action on PV Platforms
Creators: name: Scaletchi, I.
name: Visa, I.
name: Velicu, R.
name: Moldovan, M.
Publisher: name: WIP
Year: 2011
Subjects: Components for PV Systems
PV Modules

description: 26th European Photovoltaic Solar Energy Conference and Exhibition; 3556-3559
description: During the embodiment design stage of a tracking system for PV platforms, an important step is to
determine loads as inputs for dimensioning of mechanical transmission and of the entire structure. Wind action is one of
the most important loads on these kind of mechanical systems. An important issue is to establish the torque acting on
panels, due to wind action. This paper is presenting a FEM simulation of wind action on PV panels, the results being
compared with the existing data from standards or reports from important companies and also experimental results.
Novel PV Module Cleaning System Using Ambient Moisture
Creators: name: John, J.J.
name: Raval, M.C.
name: Kottantharayil, A.
name: Singh Solanki, C.S.
Publisher: name: WIP
Year: 2011
Subjects: Components for PV Systems
PV Modules

description: 26th European Photovoltaic Solar Energy Conference and Exhibition; 3569-3571
description: Effective cleaning of PV modules in field installations is important to ensure maximum energy output.
The loss of energy generation from module due to dust and other obstructions can be significant, particularly in
tropical climates. Other than energy loss, there could be module-level failure due to hot spots resulting in unclean
modules. In this work, a novel prototype cleaning system has been developed which is based on ambient moisture
absorption by deliquescent substances. The system is designed to perform module cleaning on daily basis without any
human intervention. Data on amount of water-vapor absorption over a period of 100 hours and 300 hours for various
deliquescent substances have been collected along with variation in environmental factors like relative humidity and
temperature. Best moisture absorption result with a weight gain of 133% was obtained. Water is separated from the
obtained solution by a unit designed on the principle of evaporation and condensation. Finally a complete proto type
system for module cleaning is presented.
Analysis of Heating Effect on the Deposition Process of High Rate Microcrystalline Silicon
Creators: name: Zhang, X.
name: Zhang, H.
name: Wei, C.
name: Sun, J.
name: Hou, G.
name: Xiong, S.
name: Geng, X.
name: Zhao, Y.
Publisher: name: WIP-Munich
Year: 2009
Subjects: Thin Films Solar Cells
Amorphous and Microcrystalline Silicon Solar Cells

description: 24th European Photovoltaic Solar Energy Conference, 21-25 September 2009, Hamburg, Germany; 2623-2626
description: During the high rate deposition process of hydrogenated microcrystalline silicon(μc-Si:H) thin film in
plasma enhanced chemical phase deposition(PECVD), some kinds of heating effects may occur to increase the
substrate temperature, arising from the excitation power heat accumulation and the change of the inter-electrode
distance or the total gas flow. This paper demonstrates that, though in different ways, all of these heating effects
could gradually modify the μc-Si:H structural properties with deposition time, and a higher input power combined
with a smaller inter-electrode distance, often used in high rate deposition, could bring a stronger heating effect. Thus
we propose both of them should be suitable as much as possible, especially for the device-grade quality μc-Si:H
material.
LPCVD Growth of ZnO for Solar Cell Applications
Creators: name: Nicolay, S.
name: Faÿ, S.
name: Ballif, C.
Publisher: name: WIP-Munich
Year: 2009
Subjects: Thin Films Solar Cells
Amorphous and Microcrystalline Silicon Solar Cells

description: 24th European Photovoltaic Solar Energy Conference, 21-25 September 2009, Hamburg, Germany; 2699-2701
description: A growth model for the low pressure chemical vapor deposition (LPCVD) of polycrystalline ZnO thin
films is proposed. This model is based on experimental observations of the surface morphology and crystallographic
orientations of the layers at different thicknesses and growth temperatures. It is shown that the films preferred
orientation evolves from c-axis to a-axis as the growth temperature is. At the same time, when the film thickness
increases, the surface morphology evolves from small rounded grains to large pyramids at a growth temperature of
150°C. The selection of various preferential orientations under different deposition conditions is attributed to growth
competition between clusters initially formed with different crystallographic orientations.
Determination of Fire Safety Risks at PV Systems and Development of Risk Minimization Measures
Creators: name: Reil, F.
name: Vaassen, W.
name: Sepanski, A.
name: V. Heeckeren, B.
name: Gülenc, F.
name: Schmidt, H.
name: Grab, R.
name: Bopp, G.
name: Laukamp, H.
name: Phillip, S.
name: Thiem, H.
name: Richter, A.
name: Krutzke, A.
name: Haselhuhn, R.
name: Halfmann, M.
name: Volkenborn, F.
name: Häberlin, H.
Publisher: name: WIP
Year: 2011
Subjects: Components for PV Systems
PV Modules

description: 26th European Photovoltaic Solar Energy Conference and Exhibition; 3553-3555
description: Since different discussions and research work in the recent past have contributed significantly to the entire
aspect of fire risk and safety issues in photovoltaic systems, new challenges for the PV industry have evolved from these
findings. With respect to other projects and joint working groups, a German 3-year research project, co-funded by the
Federal Environment Ministry, started early 2011 to examine a wide range of fire related issues on photovoltaic products
in order to support standardization groups, fire fighters, building authorities and component as well as module
manufacturers regarding fire risks at PV systems. A broad view of the individual working packages, approaches and main
goals will be given as very promising first results.
Monitoring Equipment for Uniformity Measurement of Inline Flashers for 2.2 by 2.6m² TF-Module Production
Creators: name: Sorge, S.
name: Gatzlaff, C.
name: Reinecke, M.
name: Stegemann, K.H.
Publisher: name: WIP-Munich
Year: 2009
Subjects: Thin Films Solar Cells
Amorphous and Microcrystalline Silicon Solar Cells

description: 24th European Photovoltaic Solar Energy Conference, 21-25 September 2009, Hamburg, Germany; 2702-2703
description: Large TF-solar modules will have a great impact on PV installations and cutting costs per watt. So characterization of
modules up to 2.2 by 2.6m² becomes more important. So far only few equipment manufacturers are able to assemble
flash equipment suitable for large area modules. Signet Solar is using a Berger flasher to characterize its modules the
size mentioned above in an automatic fashion. In order to gain precise measurement results flash uniformity, spectral
sensitivity match between the monitoring devices and the modules to be measured needs to be considered. To solve
the issues a circuitry to measure up to 252 cells during just one flash has been designed and a special measuring panel
containing a corresponding number of cells has been prepared. The measuring panel is prepared using the same
technology, so spectral mismatch is eliminated. The active cell area approaches 100%. Using this equipment, the
flash uniformity can be investigated during one flash in accordance to IEC60904-9 for the Gen8.5 2.2x2.6m² as well
as for the Gen5 1.1x1.3m² TF-modules. Also this equipment makes it less time consuming to measure and improve
the flash uniformity.
Determining Optimal TiO2 Layer Thickness in Dye-Sensitized Solar Cell Using A Numerical Model
Creators: name: Filipic, M.
name: Berginc, M.
name: Smole, F.
name: Topic, M.
Publisher: name: WIP
Year: 2011
Subjects: Advanced Photovoltaics : New Concepts and Ultra-High Efficiency
Organic-based PV

description: 26th European Photovoltaic Solar Energy Conference and Exhibition; 529-532
description: Numerical model of dye-sensitized solar cell consisting of two layers based on continuity and transport equations is
presented. First layer is the active layer where electron transport and generation/recombination processes occur.
Second layer is the bulk electrolyte layer where only ions diffuse. Shockley-Read-Hall statistics and Marcus-
Gerischer theory are applied to determine trapping and detrapping rates and electron transfer rates between the
semiconductor and ions in the electrolyte. Ionic liquid based dye-sensitized solar cells with different active layer
thicknesses are produced and measurements of efficiency, fill factor, open-circuit voltage and short-circuit current are
compared with the simulation results. Presented model is applied to calculate the optimal thickness of the active
layer. According to the simulation, optimal thickness of the active layer is found to be near 7 μm which is in good
agreement with measurement results.
Production and Comparison of Fully Solution Based 1D-2D-3D (ITO-TiO2) Composite Dye Sensitized Solar Cell
Creators: name: Yavuz, H.I.
name: Özenbas, A.M.
Publisher: name: WIP
Year: 2011
Subjects: Advanced Photovoltaics : New Concepts and Ultra-High Efficiency
Organic-based PV

description: 26th European Photovoltaic Solar Energy Conference and Exhibition; 551-553
description: Semiconductor metal oxide nanowires (SCMONWs), favorable materials for various quantum devices
which have 1 D interaction and huge surface-volume ratio, were synthesized by a novel technique. Growth of
nanowires is commonly performed using expensive techniques requiring high vacuum and high temperature
conditions, which also consume some hazardous raw materials. The sol-gel technique employed in this study is used
primarily for the fabrication of materials including metal oxides beginning from a wet chemical solution, where low
temperatures and non-vacuum conditions are utilized. Indium tin oxide (ITO) is primarily used as a transparent
conducting oxide for electronics such as Solar Cells and LCD applications. In this work; indium tin oxide (ITO)
nanoparticles, nanowires and thin films have been realized on glass substrates by sol-gel technique and these were
used for the production of nano-crystalline dye-sensitized solar cells (nc-DSSC), which are a relatively new class of
low-cost thin film solar cells. Structural, topographical and chemical analysis were made using XRD, SEM and EDS.
15 nm thick and 500 nm long ITO nanowires were observed in SEM analysis. The transparency of the ITO films was
analyzed using UV spectrometer. Then 5% addition of ITO nanowires in nano-crystalline DSSCs caused an
improvement of 33% in the efficiency with respect to pure TiO2 dye sensitized solar cells.
Flat Module Made of Spherical Cells in Higher Latitude Areas (Long-Term Testing Performance)
Creators: name: Rodziewicz, T.
name: Nakata, J.
name: Taira, K.
name: Zaremba, A.
name: Waclawek, M.
Publisher: name: WIP
Year: 2011
Subjects: Components for PV Systems
PV Modules

description: 26th European Photovoltaic Solar Energy Conference and Exhibition; 3576-3580
description: The performance of new-created flat module made of spherical cells (Sphelar®) in outdoor conditions
was presented. Investigations were performed in 2009 and 2010 at the Opole University. For comparison
commercially available flat PV modules were taken, namely single crystalline and multicrystalline Si modules as well
as thin-film CIS and two amorphous Si modules - single junction, marked as SJ, and triple junction, marked as TJ,
respectively. All of them were placed on the same plane. The PV data and their integral values (eg cumulated energy
and charge) of tested photovoltaic modules as well as meteorological data (insolation on the surface of modules
(measured by the detector Kipp&Zonen), relative humidity, air pressure and temperature, wind speed and direction)
were measured in 30 second period (or calculated) and stored by an acquisition data system. Additionally,
temperature of the modules was measured. Special attention was paid to analyse the comparison of normalised values
of photocurrent and cumulated energy of modules in sunny and cloudy days. Efficiency of energy generation was also
discussed.
Output Evaluation of Photovoltaic Module with Month Applied Wavelength Shifting Materials
Creators: name: Hirata, Y.
name: Nakajima, S.
name: Noro, S.
Publisher: name: WIP
Year: 2011
Subjects: Components for PV Systems
PV Modules

description: 26th European Photovoltaic Solar Energy Conference and Exhibition; 3585-3589
description: The wavelength shifting materials (WSM) absorbs short wavelength ray and fluorescence longer ray.
This characteristic presumed to apply efficient use of spectral radiation for various areas. Incident UV deteriorates the
EVA of photovoltaic (PV) module for a long period of time. Each solar cell has its spectral response. If incident
spectral solar radiation adjusted for solar cell and PV module, conversion efficiency and durability is presumed to be
improved. Red fluoresced WSM is also applied to improve photosynthetic efficiency. Therefore, WSM
characteristics for various spectral distribution of incident solar radiation should be explicit. This paper examined
how PV module output varies with season, applied WSM, and spectral solar radiation of WSM varies: WSM is
applied on the front of PV modules that fluoresces purple to amorphous silicon and red to polycrystalline silicon. To
make the most of WSM characteristics variation by absorption and fluorescence with environment such as month or
weather, conversion efficiency and durability of PV module presumed to be enhanced. The measured data should be
investigated continuously for the application method of fluorescence dye to solar cell and PV module. This study
examined two kinds WSM PV characteristic data for a year.
Silicon Solar Cells Using Aluminum Foil as Rear Side Metallization Reaching 21,0% Efficiency
Creators: name: Nekarda, J.-F.
name: Lottspeich, F.
name: Wolf, A.
name: Preu, R.
Publisher: name: WIP-Munich
Year: 2010
Subjects: Wafer-Based Silicon Solar Cells and Materials Technology
Mono- and Multicrystalline Silicon Materials and Cells

description: 25th European Photovoltaic Solar Energy Conference and Exhibition / 5th World Conference on Photovoltaic Energy Conversion, 6-10 September 2010, Valencia, Spain; 2211-2214
description: In this contribution we present the latest results of our experiments regarding the use of aluminum foil as rear
side metallization for solar cells with dielectric passivation and laser fired contacts (LFC). In this approach the foil is fixed
during the contacting process onto the wafer by local alloying of an IR laser. The proof of that concept was already shown at
the 22nd EUPVSEC conference in Milan. Meanwhile, we have optimized the overall cell process by using aluminum oxide
Al2O3 since it is a more appropriate passivation material for this approach. Furthermore, we investigated the laser process
and compared different laser parameters regarding the resistance of the contacts and the adhesion properties of the foil.
Finally, we show that the efficiency potential of the foil metallization is on the same level compared to the originally
metallization concept for LFC cells based on physical vapor deposition (PVD) by achieving efficiencies of 21.0 %.
Dielectric Rear Side Passivation on Ribbon Growth on Substrate (RGS) Solar Cells
Creators: name: Hess, U.
name: Joos, S.
name: Junge, J.
name: Seren, S.
name: Hahn, G.
name: Weber, T.
name: Pichon, P.-Y.
name: Schönecker, A.
Publisher: name: WIP-Munich
Year: 2010
Subjects: Wafer-Based Silicon Solar Cells and Materials Technology
Mono- and Multicrystalline Silicon Materials and Cells

description: 25th European Photovoltaic Solar Energy Conference and Exhibition / 5th World Conference on Photovoltaic Energy Conversion, 6-10 September 2010, Valencia, Spain; 2223-2226
description: Ribbon Growth on Substrate (RGS) silicon wafers are cast directly from the melt onto reusable
substrates. With a high production speed in the order of one wafer per second and the avoidance of material loss due
to wire-sawing like in the block-casting technology, RGS is a cost-effective material. The wafers are multicrystalline
with typical grain sizes between 0.1 mm to 1 mm. Up to now, the adapted solar cell process contained an open rear
side metallization realized by an Al-grid [1]. This had to be implemented because of increased process induced
shunting in cell areas with Al back side metallization. For rear side passivation and avoidance of possible shunting,
two new cell back side designs are tested and compared to the RGS baseline process. In this work, silicon carbide as
a dielectric passivation layer and its properties regarding a co-firing temperature step and the application of such a
layer in the RGS solar cell process is investigated. It is found that a cell process for RGS containing a dielectric layer
on the cell rear side in connection with Laser Fired Contacts (LFCs) enhances the cell performance by reducing the
area of possibly contacted shunting paths further and thus increasing the parallel resistance of the solar cells. The
gain in efficiency is hereby less attributed to the improved rear side passivation quality for this material with a limited
diffusion length.