A NEW APPROACH TO IDEAL AlGaAs MQW SOLAR CELLS

A theoretical model has been developed which shows that the insertion of multi-quantum wells into the depletion region of a p-i(MQW)-n Al x Ga 1-x As solar cell can significantly enhance the conversion efficiencies. Open-circuit voltages, short-circuit current densities, I-V curves and conversion efficiencies have been calculated as functions of the well and barrier band gaps, width and depth of the wells, number of wells in the intrinsic region and the recombination rate in the interfaces. Particular emphasis is placed on calculation of absorption of the Al x Ga 1-x As quantum wells. These results are matched with p-i-n solar cells which are identical in all respects except that they do not have quantum wells. We demonstrated that for determined values of the studied parameters the conversion efficiencies of the quantum well solar cell is higher to corresponding cell without quantum wells.

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Solar Cell Contacts Using Nano-Sized Dispersions

MRS Proceedings ◽

10.1557/proc-581-157 ◽

1999 ◽

Vol 581 ◽

Author(s):

Doug Schulz ◽

R. Ribelin ◽

X. Wu ◽

K.M. Jones ◽

R.J. Matson ◽

...

Keyword(s):

Solar Cells ◽

Spray Deposition ◽

Short Circuit ◽

Short Circuit Current ◽

Cdte Layer ◽

Open Circuit ◽

Alloy Formation ◽

Current Densities ◽

P Type ◽

Open Circuit Voltages

ABSTRACTNano-sized dispersions have been employed as precursor inks for the spray deposition of contacts to both Si and CdTe materials. In the case of Si, nano-sized Al particles (nano-Al) were dispersed and spray deposited onto p-type Si. Annealing above the eutectic temperature causes alloy formation yielding a p+ layer with p ∼ 10−4 Ω•cm. For CdTe, nano-sized Te particles (nano-Te) were dispersed and sprayed onto CdTe/CdS/SnO2/glass heterostructures. Contact to the CdTe layer occurred during a 30 min anneal in He (T = 215 to 255 °C). These solar cells were finished by spin-coating the Te layer with Ag paint and subsequently annealing in air (100 °C / 1 h). This approach produces solar cells with open circuit voltages (Voc) from 720 to 800 mV, short circuit current densities (Jsc) from 18 to 20 mA/cm2 and efficiencies up to 10.3%. The performance of these cells was similar to those produced using the standard NREL contact.

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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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GaInP/GaAs/poly-Si Multi-Junction Solar Cells by in Metal Balls Bonding

Crystals ◽

10.3390/cryst11070726 ◽

2021 ◽

Vol 11 (7) ◽

pp. 726

Author(s):

Ray-Hua Horng ◽

Yu-Cheng Kao ◽

Apoorva Sood ◽

Po-Liang Liu ◽

Wei-Cheng Wang ◽

...

Keyword(s):

Solar Cells ◽

Solar Cell ◽

Low Temperature ◽

Triple Junction ◽

Short Circuit ◽

Short Circuit Current ◽

Open Circuit ◽

Metal Line ◽

Solar Simulator ◽

Junction Solar Cell

In this study, a mechanical stacking technique has been used to bond together the GaInP/GaAs and poly-silicon (Si) solar wafers. A GaInP/GaAs/poly-Si triple-junction solar cell has mechanically stacked using a low-temperature bonding process which involves micro metal In balls on a metal line using a high-optical-transmission spin-coated glue material. Current–voltage measurements of the GaInP/GaAs/poly-Si triple-junction solar cells have carried out at room temperature both in the dark and under 1 sun with 100 mW/cm2 power density using a solar simulator. The GaInP/GaAs/poly-Si triple-junction solar cell has reached an efficiency of 24.5% with an open-circuit voltage of 2.68 V, a short-circuit current density of 12.39 mA/cm2, and a fill-factor of 73.8%. This study demonstrates a great potential for the low-temperature micro-metal-ball mechanical stacking technique to achieve high conversion efficiency for solar cells with three or more junctions.

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Study of Photoelectrochemical Solar Cell Using WSe2 Crystal

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.665.330 ◽

2013 ◽

Vol 665 ◽

pp. 330-335 ◽

Cited By ~ 1

Author(s):

Ripal Parmar ◽

Dipak Sahay ◽

R.J. Pathak ◽

R.K. Shah

Keyword(s):

Solar Cells ◽

Solar Cell ◽

Fill Factor ◽

Short Circuit ◽

Short Circuit Current ◽

Electrical Energy ◽

Open Circuit ◽

Cell Parameters ◽

Photoelectrochemical Solar Cell ◽

Photoelectrochemical Solar Cells

The solar cells have been used as most promising device to convert light energy into electrical energy. In this paper authors have attempted to fabricate Photoelectrochemical solar cell with semiconductor electrode using TMDCs. The Photoelectrochemical solar cells are the solar cells which convert the solar energy into electrical energy. The photoelectrochemical cells are clean and inexhaustible sources of energy. The photoelectrochemical solar cells are fabricated using WSe2crystal and electrolyte solution of 0.025M I2, 0.5M NaI, 0.5M Na2SO4. Here the WSe2crystals were grown by direct vapour transport technique. In our investigations the solar cell parameters like short circuit current (Isc) and Open circuit voltage (Voc) were measured and from that Fill factor (F.F.) and photoconversion efficiency (η) are investigated. The results obtained shows that the value of efficiency and fill factor of solar cell varies with the illumination intensities.

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Analytical Study of the Electrical Output Characteristics of c-Si Solar Cells by Cut and Shading Phenomena

Energies ◽

10.3390/en11123397 ◽

2018 ◽

Vol 11 (12) ◽

pp. 3397 ◽

Cited By ~ 1

Author(s):

Jong Lim ◽

Woo Shin ◽

Hyemi Hwang ◽

Young-Chul Ju ◽

Suk Ko ◽

...

Keyword(s):

Solar Cells ◽

Solar Cell ◽

Crystalline Silicon ◽

Short Circuit ◽

Incident Light ◽

Short Circuit Current ◽

Open Circuit ◽

Si Solar Cell ◽

Si Solar Cells ◽

Electrical Output

Cut solar cells have received considerable attention recently as they can reduce electrical output degradation when the c-Si solar cells (crystalline-silicon solar cells) are shaded. Cut c-Si solar cells have a lower short-circuit current than normal solar cells and the decrease in short-circuit currents is similar to the shading effect of c-Si solar cells. However, the results of this study’s experiment show that the shadow effect of a c-Si solar cell reduces the V o c (open circuit voltage) in the c-Si solar cell but the V o c does not change when the c-Si solar cell is cut because the amount of incident light does not change. In this paper, the limitations of the electrical power analysis of the cut solar cells were identified when only photo current was considered and the analysis of the electric output of the cut c-Si solar cells was interpreted with a method different from that used in previous analyses. Electrical output was measured when the shaded and cut rates of c-Si solar cells were increased from 0% to 25, 50 and 75%, and a new theoretical model was compared with the experimental results using MATLAB.

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Preparation of the Three Main Layers of CdS/CdTe Thin Film Solar Cells Using a Single Vacuum System

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.378-379.601 ◽

2011 ◽

Vol 378-379 ◽

pp. 601-605 ◽

Cited By ~ 1

Author(s):

Saleh N. Alamri ◽

M. S. Benghanem ◽

A. A. Joraid

Keyword(s):

Thin Film ◽

Solar Cells ◽

Solar Cell ◽

Short Circuit ◽

Short Circuit Current ◽

Short Circuit Current Density ◽

Open Circuit ◽

Fused Silica ◽

Vacuum System ◽

Cdte Thin Film

This study investigates the preparation of the three main layers of a CdS/CdTe thin film solar cell using a single vacuum system. A Close Space Sublimation System was constructed to deposit CdS, CdTe and CdCl2 solar cell layers. Two hot plates were used to heat the source and the substrate. Three fused silica melting dishes were used as containers for the sources. The properties of the deposited CdS and CdTe films were determined via Atomic force microscopy, scanning electron microscopy, X-ray diffraction and optical transmission spectroscopy. An J-V characterization of the fabricated CdS/CdTe solar cells was performed under solar radiation. The short-circuit current density, Jsc, the open-circuit voltage, Voc, fill factor, FF and conversion efficiency, η, were measured and yielded values of 27 mA/cm2, 0.619 V, 58% and 9.8%, respectively.

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Improvement of short circuit current of mono crystalline silicon solar cells

Science and Technology Development Journal ◽

10.32508/stdj.v16i1.1418 ◽

2013 ◽

Vol 16 (1) ◽

pp. 48-56

Author(s):

Vu Ngoc Hoang ◽

Linh Ngoc Tran ◽

Lan Truong ◽

Khoa Thanh Nhat Phan ◽

Chien Mau Dang ◽

...

Keyword(s):

Solar Cells ◽

Solar Cell ◽

Indium Tin Oxide ◽

Crystalline Silicon ◽

Short Circuit ◽

Front Surface ◽

Short Circuit Current ◽

Open Circuit ◽

Crystalline Silicon Solar Cell ◽

Antireflection Coatings

In this report we present series of experiments during which the short circuit current of mono crystalline silicon solar cell was improved step by step so as a consequence the efficiency was increased. At first, the front contact of solar cell was optimized to reduce the shadow loss and the series resistance. Then surface treatments were prepared by TMAH solution to reduce the total light reflectance and to improve the light trapping effect. Finally, antireflection coatings were deposited to passivate the front surface either by silicon nitride thin layer or to increase the collection probability by indium tin oxide layer, and to reduce the reflectance of light. As a result, solar cells of about 13% have been obtained, with the average open circuit voltage Voc about 527mV, with the fill factor about 68% and the short circuit current about 7.92 mA/cm2 under the irradiation density of 21 mW/cm2.

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Numerical Modeling of the Electronic and Electrical Characteristics of InGaN/GaN-MQW Solar Cells

Materials ◽

10.3390/ma12081241 ◽

2019 ◽

Vol 12 (8) ◽

pp. 1241 ◽

Cited By ~ 5

Author(s):

Bilel Chouchen ◽

Mohamed Hichem Gazzah ◽

Abdullah Bajahzar ◽

Hafedh Belmabrouk

Keyword(s):

Solar Cells ◽

Quantum Wells ◽

Negative Impact ◽

Positive Impact ◽

Short Circuit ◽

Short Circuit Current ◽

Short Circuit Current Density ◽

Open Circuit ◽

Effect Of Temperature ◽

Photovoltaic Parameters

In this paper, a numerical model allows to analyze the photovoltaic parameters according to the electronic properties of InxGa1−xN/GaN MQW solar cells under the effect of temperature, the number of quantum wells and indium composition. The numerical investigation starts from the evaluation through the finite difference (FDM) simulation of the self-consistent method coupled with the photovoltaic parameters taking into account the effects of the spontaneous and piezoelectric polarization. The results found were consistent with the literature. As expected, the temperature had a negative impact on the performance of InGaN/GaN MQW solar cells. However, increasing the number of quantum wells improves cell performance. This positive impact further improves with the increase in the indium rate. The obtained results were 28 mA/cm2 for the short-circuit current density, 1.43 V for the open-circuit voltage, and the obtained conversion efficiency was 31% for a model structure based on 50-period InGaN/GaN-MQW-SC under 1-sun AM1.5G.

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All Solution-Based Fabrication of CIGS Solar Cell

Volume 2: Systems; Micro and Nano Technologies; Sustainable Manufacturing ◽

10.1115/msec2013-1239 ◽

2013 ◽

Author(s):

Robert L. Vittoe ◽

Tung Ho ◽

Sudhir Shrestha ◽

Mangilal Agarwal ◽

Kody Varahramyan

Keyword(s):

Solar Cells ◽

Solar Cell ◽

Copper Chloride ◽

Short Circuit ◽

Spray Coating ◽

Short Circuit Current ◽

Open Circuit ◽

Layer By Layer ◽

Zinc Oxide Film ◽

Indium Chloride

This paper presents fabrication of copper indium gallium di-selenide (CIGS) solar cells using all solution-based deposition processes. CIGS nanoparticles were synthesized through multi-step chemical process using copper chloride, indium chloride, gallium chloride, and selenium in oleyamine. CIGS thin films were constructed through layer-by-layer (LbL) self-assembly and spray-coating techniques. Chemical-bath-deposition and spray-coating methods were used for cadmium sulfide and zinc oxide film depositions, respectively. Initial thin film solar cell devices exhibited promising 0.3 mA short circuit current and 200 mV open circuit voltage. The solar cells fabricated through the all solution-based processes are cost-effective, thus, have potentials of providing a viable, renewable and sustainable energy source. The proposed processes can further be realized on flexible substrates, which may broaden the applications range for the solar cells.

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Preparation of Narrow-gap a-Si:H Solar Cells by VHF-PECVD Technique

MRS Proceedings ◽

10.1557/proc-1245-a07-07 ◽

2010 ◽

Vol 1245 ◽

Author(s):

Do Yun Kim ◽

Ihsanul Afdi Yunaz ◽

Shunsuke Kasashima ◽

Shinsuke Miyajima ◽

Makoto Konagai

Keyword(s):

Thin Films ◽

Solar Cells ◽

Solar Cell ◽

Spectral Response ◽

Short Circuit ◽

Short Circuit Current ◽

Short Circuit Current Density ◽

Open Circuit ◽

Hydrogen Flow ◽

Long Wavelength

AbstractOptical, electrical and structural properties of silicon films depending on hydrogen flow rate (RH), substrate temperature (TS), and deposition pressure (PD) were investigated. By decreasing RH and increasing TS and PD, the optical band gap (Eopt) of silicon thin films drastically declined from 1.8 to 1.63 eV without a big deterioration in electrical properties. We employed all the investigated Si thin films for p-i-n structured solar cells as absorbers with i-layer thickness of 300 nm. From the measurement of solar cell performances, it was clearly observed that spectral response in long wavelength was enhanced as Eopt of absorber layers decreased. Using the solar cell whose Eopt of i-layer was 1.65 eV, the highest QE at long wavelength with the short circuit current density (Jsc) of 16.34 mA/cm2 was achieved, and open circuit voltage (Voc), fill factor (FF), and conversion efficiency (η) were 0.66 V, 0.57, and 6.13%, respectively.

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