Comparative Analysis, Simulation and Optimization of Current Density-Voltage Characteristics of CIGS and CZTS Thin Film Solar Cells

A precise characterization of thin-film solar cells is of huge importance for obtaining high open-circuit voltage and low recombination rates from the interfaces or within the bulk of the main materials. Among many electrical characterization techniques, the two- and four-wire probe using the Cascade instrument is of interest since the resistance of the wires and the electrical contacts can be excluded by the additional two wires in four-wire probe configuration. In this paper, both two- and four-point probes configuration are employed to characterize the CIGS chalcogenide thin-film solar cells. The two-wire probe has been used to measure the current–voltage characteristics of the cell which results in a huge internal resistance. Therefore, the four-wire connection is also used to eliminate the load resistance to enhance the characterization’s accuracy. The load resistance in the two-wire probe diminishes the photogenerated current density at smaller voltage ranges. In contrast, the proposed four-wire probe collects more current at higher voltages due to enhanced carrier collection efficiency from contact electrodes. The current conduction mechanism is also identified at every voltage region represented by the value of the ideality factor of that voltage region. It is observed that a longer time given to the charge collection results in increased current density at a higher voltage. According to the results and device characteristics, a novel double-diode model is suggested to extract the saturation current density, shunt and series resistances and ideality factor of the cells. These cells are shown to be efficient in terms of low recombination at the interfaces and with lower series resistance as the quality of the materials is in its most possible conductive form. The measured internal resistance and saturation current density and ideality factor of the two measurement configurations are measured and compared.

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Nanoimprint Photonic Crystal Film Enhanced Light-Trapping in a-Si Thin Film Solar Cells

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.110-116.497 ◽

2011 ◽

Vol 110-116 ◽

pp. 497-502

Author(s):

Wei Ping Chu ◽

Fuh Shyang Juang ◽

Jian Shian Lin ◽

Tien Chai Lin ◽

Chen Wei Kuo

Keyword(s):

Thin Film ◽

Solar Cells ◽

Photonic Crystals ◽

Current Density ◽

Light Trapping ◽

Short Circuit ◽

Short Circuit Current ◽

Short Circuit Current Density ◽

Thin Film Solar Cells ◽

Uv Lamp

We utilize photonic crystals to enhanced lighttrapping in a-Si:H thin film solar cells. The photonic crystals effectively increase Haze ratio of glass and decrease reflectance of a-Si:H solar cells. Therefore, increase the photon path length to obtain maximum absorption of the absorber layer. The photonic crystals can effective in harvesting weakly absorbing photons with energies just above the band edge. We were spin coated UV glue on the glass, and then nanoimprint of photonic crystals pattern. Finally, used UV lamp was curing of UV glue on the glass. When the 45∘composite photonic crystals structures, the haze was increase to 87.9 %, resulting the short circuit current density and efficiency increasing to 13.96 mA/cm2 and 7.39 %, respectively. Because 45∘composite photonic crystals easy to focus on the point of light lead to the effect of scattering can’t achieve. So, we designs 90∘V-shaped photonic crystals structures to increase scattering. When the 90∘V-shaped photonic crystals structures, the Haze was increase to 93.9 %. Therefore, the short circuit current density and Efficiency increasing to 15.62 mA/cm2 and 8.09 %, respectively. We observed ~35 % enhancement of the short-circuit current density and ~31 % enhancement of the conversion efficiency.

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Current status and future prospects of kesterite CZTS thin film solar cells

International Photonics and Optoelectronics Meetings (POEM) ◽

10.1364/aoee.2013.asu3a.2 ◽

2013 ◽

Author(s):

Yanqing Lai ◽

Zhenghua Su ◽

Fangyang Liu ◽

Jie Li ◽

Yexiang Liu

Keyword(s):

Thin Film ◽

Solar Cells ◽

Thin Film Solar Cells ◽

Czts Thin Film ◽

Current Status ◽

Future Prospects

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The Development of CZTS Thin Films for Solar Cells

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.182-183.237 ◽

2012 ◽

Vol 182-183 ◽

pp. 237-240

Author(s):

Nian Jing Ji ◽

Ke Gao Liu ◽

Zhong Quan Ma

Keyword(s):

Thin Film ◽

Crystal Structure ◽

Thin Films ◽

Solar Cells ◽

Thin Film Solar Cells ◽

Czts Thin Film ◽

Potential Candidate ◽

Composition Ratio ◽

Photoelectric Performance ◽

Czts Thin Films

CZTS thin film, a potential candidate for application as absorber layer in thin film solar cells, has drawn much attention in these years due to its excellent photoelectric performance and nontoxic components. It provides a brief description of the development of CZTS thin film for solar cells, and surveys several methods of depositing CZTS films, then introduces the crystal structure of CZTS which is a problem for composition ratio affecting the properties of CZTS thin films. Here we also outline the development and the structure of solar cells based on CZTS thin films.

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