Improving Performance of Amorphous Silicon Solar Cells Using Tungsten Oxide as a Novel Buffer Layer between the SnO2/p-a-SiC Interface

AbstractA thermally evaporated p-type amorphous tungsten oxide (p-a-WO3) film was introduced as a novel buffer layer between SnO2 and p-type amorphous silicon carbide (p-a-SiC) of pin-type amorphous silicon (a-Si) based solar cells. By using this film, a-Si solar cells with a p-a-WO3/p-a-SiC double p-layer structure were fabricated and the cell photovoltaic characteristics were investigated as a function of p-a-WO3 layer thickness. By inserting a 2 nm-thick p-a-WO3 layer between SnO2 and a 6 nm-thick p-a-SiC layer, the short circuit current density increased from 9.73 to 10.57 mA/cm2, and the conversion efficiency was enhanced from 5.17 % to 5.98 %.

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Realization of Colored Multicrystalline Silicon Solar Cells with SiO2/SiNx:H Double Layer Antireflection Coatings

International Journal of Photoenergy ◽

10.1155/2013/352473 ◽

2013 ◽

Vol 2013 ◽

pp. 1-8 ◽

Cited By ~ 18

Author(s):

Minghua Li ◽

Libin Zeng ◽

Yifeng Chen ◽

Lin Zhuang ◽

Xuemeng Wang ◽

...

Keyword(s):

Solar Cells ◽

Double Layer ◽

Short Circuit ◽

Single Layer ◽

Short Circuit Current ◽

Industrial Applications ◽

Short Circuit Current Density ◽

Multicrystalline Silicon ◽

Antireflection Coatings ◽

Si Solar Cells

We presented a method to use SiO2/SiNx:H double layer antireflection coatings (DARC) on acid textures to fabricate colored multicrystalline silicon (mc-Si) solar cells. Firstly, we modeled the perceived colors and short-circuit current density (Jsc) as a function of SiNx:H thickness for single layer SiNx:H, and as a function of SiO2thickness for the case of SiO2/SiNx:H (DARC) with fixed SiNx:H (refractive indexn=2.1at 633 nm, and thickness = 80 nm). The simulation results show that it is possible to achieve various colors by adjusting the thickness of SiO2to avoid significant optical losses. Therefore, we carried out the experiments by using electron beam (e-beam) evaporation to deposit a layer of SiO2over the standard SiNx:H for156×156 mm2mc-Si solar cells which were fabricated by a conventional process. Semisphere reflectivity over 300 nm to 1100 nm andI-Vmeasurements were performed for grey yellow, purple, deep blue, and green cells. The efficiency of colored SiO2/SiNx:H DARC cells is comparable to that of standard SiNx:H light blue cells, which shows the potential of colored cells in industrial applications.

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Hydrogenated amorphous silicon germanium by Hot Wire CVD as an alternative for microcrystalline silicon in tandem and triple junction solar cells

MRS Proceedings ◽

10.1557/opl.2014.683 ◽

2014 ◽

Vol 1666 ◽

Cited By ~ 3

Author(s):

L.W. Veldhuizen ◽

Y. Kuang ◽

N.J. Bakker ◽

C.H.M. van der Werf ◽

S.-J. Yun ◽

...

Keyword(s):

Solar Cells ◽

Amorphous Silicon ◽

Band Gap ◽

Silicon Germanium ◽

Short Circuit ◽

Hydrogenated Amorphous Silicon ◽

Short Circuit Current ◽

Short Circuit Current Density ◽

Amorphous Silicon Germanium ◽

Hydrogenated Amorphous

ABSTRACTWe study hydrogenated amorphous silicon germanium (a-SiGe:H) deposited by HWCVD for the use as low band gap absorber in multijunction junction solar cells. We deposited layers with Tauc optical band gaps of 1.21 to 1.56 eV and studied the hydrogen bonding with FTIR for layers that were deposited at several reaction pressures. For our reaction conditions, we found an optimal reaction pressure of 38 µbar. The material that is obtained under these conditions does not meet all device quality requirements for a-SiGe:H, which is, as we hypothesize, caused by the presence of He that is used to dilute the GeH4 source gas. We present an initial single junction n-i-p solar cell with a Tauc optical band gap of 1.45 eV and a short circuit current density of 18.7 mA/cm2.

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Photovoltaic Characteristics of Ultra-Thin Single Crystalline Silicon Solar Cells

International Journal of High Speed Electronics and Systems ◽

10.1142/s0129156416400085 ◽

2016 ◽

Vol 25 (01n02) ◽

pp. 1640008

Author(s):

R. Miyazawa ◽

H. Wakabayashi ◽

K. Tsutsui ◽

H. Iwai ◽

K. Kakushima

Keyword(s):

Solar Cells ◽

Crystalline Silicon ◽

Spectral Response ◽

Short Circuit ◽

Short Circuit Current ◽

Open Circuit ◽

Response Measurement ◽

Single Crystalline ◽

Si Solar Cells ◽

Photovoltaic Characteristics

Photovoltaic characteristics of ultra-thin single crystalline Si solar cells with thicknesses ranging from 7.6 to 3.3 nm are presented. While the short-circuit current (ISC) AM1.5 illumination has shown a linear relationship with the volume of the Si layer, a gradual increase in the open-circuit voltage (VOC) with thinner Si layer has been confirmed, implying the bandgap enlargement of the Si layer due to quantum confinement. Spectral response measurement has revealed an increased optical bandgap of 1.3 eV for 3.3-nm-thick Si solar cells, which is wider than that of 7.6-nm-thick Si ones. Although some process related issues have become clear during the fabrication of solar cells, they can be utilized as top cells for tandem configurations, exceeding the limit of the bulk Si solar cells.

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Amorphous Crystalline Silicon Heterojunction with Silicon Nitride Buffer Layer

MRS Proceedings ◽

10.1557/proc-609-a13.4 ◽

2000 ◽

Vol 609 ◽

Cited By ~ 3

Author(s):

G. Claudio ◽

R. De Rosa ◽

F. Roca ◽

D. Caputo ◽

M. Tucci

Keyword(s):

Silicon Nitride ◽

Amorphous Silicon ◽

Buffer Layer ◽

Crystalline Silicon ◽

Short Circuit ◽

Wavelength Region ◽

Visible Spectrum ◽

Short Circuit Current ◽

Short Circuit Current Density ◽

Deposition Parameters

ABSTRACTIn this work we study the possibility to use amorphous silicon nitride, grown by plasma, as an alternative way to realize buffer layer in a-Si:H/c-Si heterostructure. We experimented several growing condition for silicon nitride depending on deposition parameters, obtaining samples highly transparent and with optical gap varying in the range 2.4 – 5.2 eV. We found evidence that the gap of the material is principally due to the NH3/N2 ratio. The very low absorption obtainable on this material was successfully utilized to increase the short circuit current density of the device respect to the standard cell with intrinsic amorphous silicon buffer, particularly in the low wavelength region as confirmed by quantum yield measurements. We optimized the thickness of the SiNx buffer layer respect to the photovoltaic parameters of the solar cell. A 0.5 nm thick SiNx ensures good photogeneration in blue region of the visible spectrum and does not appreciably degrade the transport mechanism of the heterojunction.

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Numerical Simulation of Copper Indium Gallium Diselenide Solar Cells Using One Dimensional SCAPS Software

Journal of the Nigerian Society of Physical Sciences ◽

10.46481/jnsps.2021.133 ◽

2021 ◽

pp. 48-58

Author(s):

C. O. Lawani ◽

G. J. Ibeha ◽

Olumide Ige ◽

Eli Danladi ◽

J. O. Emmanuela ◽

...

Keyword(s):

Solar Cells ◽

Buffer Layer ◽

Layer Thickness ◽

Defect Density ◽

Short Circuit ◽

Short Circuit Current ◽

Short Circuit Current Density ◽

Copper Indium Gallium Diselenide ◽

Buffer Layer Thickness ◽

Cigs Solar Cells

The effect of multivalent defect density, thickness of absorber and buffer layer thickness on the performance of CIGS solar cells were investigated systematically. The study was carried out using Solar Cells Capacitance Simulator (SCAPS) code, which is capable of solving the basic semiconductor equations. Employing numerical modelling, a solar cell with the structure Al|ZnO : Al|In2S3|CIGS|Pt was simulated and in it, a double acceptor defect (-2/-1/0) with a density of 1014 cm-3 was set in the absorber in the first instance. This initial device gave a power conversion efficiency (PCE) of 25.85 %, short circuit current density (Jsc) of 37.9576 mAcm-2, Photovoltage (Voc) of 0.7992 V and fill factor (FF) of 85.22 %. When the density of multivalent defect (-2/-1/0) was varied between 1010 cm-3 and 1017 cm-3 the solar cells performance dropped from 26.81 % to 16.87 %. The champion device was with multivalent defect of 1010 cm-3 which shows an enhancement of 3.71 % from the pristine device. On varying the CIGS layer thickness from 0.4 um to 3.6 um, an increase in PCE was observed from 0.4 um to 1.2 um then the PCE began to decrease beyond a thickness of 1.2 um. The best PCE was recorded with thickness of 1.2 um which gave Jsc of 37.7506 mAcm-2, Voc of 0.8059 V, FF of 85.2655 %. On varying the In2S3 (buffer) layer thickness from 0.01 um to 0.08 um, we observed that there was no significant change in photovoltaic parameters of the solar cells as buffer layer thickness increased.

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a-Si/c-Si Solar Cells: Effect of Preparation and Processing Techniques on the Photovoltaic Properties

MRS Proceedings ◽

10.1557/proc-426-77 ◽

1996 ◽

Vol 426 ◽

Cited By ~ 1

Author(s):

B. Jagannathan ◽

W. A. Anderson

Keyword(s):

Solar Cells ◽

Carrier Transport ◽

Crystalline Silicon ◽

Spectral Response ◽

Short Circuit ◽

Short Circuit Current ◽

Short Circuit Current Density ◽

Photovoltaic Properties ◽

Si Solar Cells ◽

Processing Techniques

AbstractThe photovoltaic (PV) properties of undoped amorphous silicon (a-Si)/ p-type crystalline silicon (c-Si) solar cells were found to improve by a hydrofluoric acid treatment of c-Si just prior to glow discharge deposition of a-Si. The short circuit current density (Jsc) improved from 2.7 to 23.5 mA/cm2 for an 0.1 μm thick a-Si layer. This also resulted in an improved spectral response of the solar cell in the violet region of the spectrum. The enhanced properties have been attributed to the improved carrier transport across the interface, as seen in the current-voltage-temperature relationships, and also PC-1D simulation of the devices. Solar cells of a similar type were also fabricated by dc magnetron sputtering of the a-Si layer. HF passivated cells (area ∼ 0.24 cm2) yielded about 9.5 % efficiency with Jsc of 30 mA/cm2 and a FF of 0.6, without use of an A/R coating. The variation of the PV properties of these cells was investigated as a function of a-Si thickness and c-Si doping.

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Investigation of Cu(In, Ga)Se2 solar cell performance with non-cadmium buffer layer using TCAD-SILVACO

Materials Science-Poland ◽

10.2478/msp-2018-0054 ◽

2018 ◽

Vol 36 (3) ◽

pp. 514-519

Author(s):

Bechlaghem Sara ◽

Zebentout Baya ◽

Benamara Zineb

Keyword(s):

Solar Cells ◽

Solar Cell ◽

Buffer Layer ◽

Short Circuit ◽

Short Circuit Current ◽

Short Circuit Current Density ◽

Open Circuit ◽

Optical Parameters ◽

Solar Cell Performance ◽

Photovoltaic Parameters

AbstractThe purpose of this work is to achieve the best efficiency of Cu(In, Ga)Se2 solar cells by replacing the CdS buffer layer with other nontoxic materials. The simulation tool used in this study is Silvaco-Atlas package based on digital resolution 2D transport equations governing the conduction mechanisms in semiconductor devices. The J-V characteristics are simulated under AM1.5G illumination. Firstly, we will report the modeling and simulation results of CdS/CIGS solar cell, in comparison with the previously reported experimental results [1]. Secondly, the photovoltaic parameters will be calculated with CdS buffer layer and without any buffer layer to understand its impact on the output parameters of solar cells. The simulation is carried out with the use of electrical and optical parameters chosen judiciously for different buffers (CdS, ZnOS and ZnSe). In comparison to simulated CdS/CIGS, the best photovoltaic parameters have been obtained with ZnOS buffer layer. The structure has almost the same open circuit voltage Voc and fill factor FF, and higher short circuit current density Jsc, which results in slightly higher conversion efficiencies.

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Determining the exciton diffusion length of copper phthalocyanine in operating planar-heterojunction organic solar cells

The European Physical Journal Applied Physics ◽

10.1051/epjap/2020190322 ◽

2020 ◽

Vol 89 (3) ◽

pp. 30201 ◽

Cited By ~ 1

Author(s):

Xi Guan ◽

Shiyu Wang ◽

Wenxing Liu ◽

Dashan Qin ◽

Dayan Ban

Keyword(s):

Solar Cells ◽

Organic Solar Cells ◽

Diffusion Length ◽

Copper Phthalocyanine ◽

Short Circuit ◽

Thick Layer ◽

Short Circuit Current ◽

Short Circuit Current Density ◽

Exciton Diffusion ◽

Exciton Diffusion Length

Organic solar cells based on planar copper phthalocyanine (CuPc)/C60 heterojunction have been characterized, in which a 2 nm-thick layer of bathocuproine (BCP) is inserted into the CuPc layer. The thin layer of BCP allows hole current to tunnel it through but blocks the exciton diffusion, thereby altering the steady-state exciton profile in the CuPc zone (zone 1) sandwiched between BCP and C60. The short-circuit current density (JSC) of device is limited by the hole-exciton scattering effect at the BCP/CuPc (zone 1) interface. Based on the variation of JSC with the width of zone 1, the exciton diffusion length of CuPc is deduced to be 12.5–15 nm. The current research provides an easy and helpful method to determine the exciton diffusion lengths of organic electron donors.

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The Influence of the Thickness of Compact TiO2 Electron Transport Layer on the Performance of Planar CH3NH3PbI3 Perovskite Solar Cells

Materials ◽

10.3390/ma14123295 ◽

2021 ◽

Vol 14 (12) ◽

pp. 3295

Author(s):

Andrzej Sławek ◽

Zbigniew Starowicz ◽

Marek Lipiński

Keyword(s):

Solar Cells ◽

Electron Transport ◽

Short Circuit ◽

Photovoltaic Performance ◽

Perovskite Solar Cells ◽

Precursor Solution ◽

Short Circuit Current ◽

Short Circuit Current Density ◽

Transport Layer ◽

Electron Transport Layer

In recent years, lead halide perovskites have attracted considerable attention from the scientific community due to their exceptional properties and fast-growing enhancement for solar energy harvesting efficiency. One of the fundamental aspects of the architecture of perovskite-based solar cells (PSCs) is the electron transport layer (ETL), which also acts as a barrier for holes. In this work, the influence of compact TiO2 ETL on the performance of planar heterojunction solar cells based on CH3NH3PbI3 perovskite was investigated. ETLs were deposited on fluorine-doped tin oxide (FTO) substrates from a titanium diisopropoxide bis(acetylacetonate) precursor solution using the spin-coating method with changing precursor concentration and centrifugation speed. It was found that the thickness and continuity of ETLs, investigated between 0 and 124 nm, strongly affect the photovoltaic performance of PSCs, in particular short-circuit current density (JSC). Optical and topographic properties of the compact TiO2 layers were investigated as well.

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CdTe-Based Thin Film Solar Cells: Past, Present and Future

Energies ◽

10.3390/en14061684 ◽

2021 ◽

Vol 14 (6) ◽

pp. 1684

Author(s):

Alessandro Romeo ◽

Elisa Artegiani

Keyword(s):

Thin Film ◽

Solar Cells ◽

Solar Cell ◽

Short Circuit ◽

Short Circuit Current ◽

Short Circuit Current Density ◽

Open Circuit ◽

Early Years ◽

Solar Cell Efficiency ◽

Cell Efficiency

CdTe is a very robust and chemically stable material and for this reason its related solar cell thin film photovoltaic technology is now the only thin film technology in the first 10 top producers in the world. CdTe has an optimum band gap for the Schockley-Queisser limit and could deliver very high efficiencies as single junction device of more than 32%, with an open circuit voltage of 1 V and a short circuit current density exceeding 30 mA/cm2. CdTe solar cells were introduced at the beginning of the 70s and they have been studied and implemented particularly in the last 30 years. The strong improvement in efficiency in the last 5 years was obtained by a new redesign of the CdTe solar cell device reaching a single solar cell efficiency of 22.1% and a module efficiency of 19%. In this paper we describe the fabrication process following the history of the solar cell as it was developed in the early years up to the latest development and changes. Moreover the paper also presents future possible alternative absorbers and discusses the only apparently controversial environmental impacts of this fantastic technology.

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