Modelling of high-efficiency substrate CIGS solar cells with ultra-thin absorber layer

In this paper, we propose an optimized structure of thin Cu(In,Ga)Se2 (CIGS) solar cells with a grating aluminum oxide (Al2O3) passivation layer (GAPL) providing nano-sized contact openings in order to improve power conversion efficiency using optoelectrical simulations. Al2O3 is used as a rear surface passivation material to reduce carrier recombination and improve reflectivity at a rear surface for high efficiency in thin CIGS solar cells. To realize high efficiency for thin CIGS solar cells, the optimized structure was designed by manipulating two structural factors: the contact opening width (COW) and the pitch of the GAPL. Compared with an unpassivated thin CIGS solar cell, the efficiency was improved up to 20.38% when the pitch of the GAPL was 7.5–12.5 μm. Furthermore, the efficiency was improved as the COW of the GAPL was decreased. The maximum efficiency value occurred when the COW was 100 nm because of the effective carrier recombination inhibition and high reflectivity of the Al2O3 insulator passivation with local contacts. These results indicate that the designed structure has optimized structural points for high-efficiency thin CIGS solar cells. Therefore, the photovoltaic (PV) generator and sensor designers can achieve the higher performance of photosensitive thin CIGS solar cells by considering these results.

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Improvement in the performance of CIGS solar cells by introducing GaN nanowires on the absorber layer

Journal of Alloys and Compounds ◽

10.1016/j.jallcom.2018.11.297 ◽

2019 ◽

Vol 779 ◽

pp. 643-647 ◽

Cited By ~ 3

Author(s):

Jae-Kwan Sim ◽

Dae-Young Um ◽

Jong-Woong Kim ◽

Jin-Soo Kim ◽

Kwang-Un Jeong ◽

...

Keyword(s):

Solar Cells ◽

Absorber Layer ◽

Gan Nanowires ◽

Cigs Solar Cells

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High efficiency CIGS solar cells on flexible stainless steel substrate with SiO2 diffusion barrier layer

Solar Energy ◽

10.1016/j.solener.2021.11.006 ◽

2021 ◽

Vol 230 ◽

pp. 1033-1039

Author(s):

Chen Zhang ◽

Tongqing Qi ◽

Wei Wang ◽

Chenchen Zhao ◽

Shuda Xu ◽

...

Keyword(s):

Stainless Steel ◽

Solar Cells ◽

Barrier Layer ◽

Diffusion Barrier ◽

High Efficiency ◽

Stainless Steel Substrate ◽

Steel Substrate ◽

Diffusion Barrier Layer ◽

Cigs Solar Cells

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Complex Investigation of High Efficiency and Reliable Heterojunction Solar Cell Based on an Improved Cu2O Absorber Layer

Energies ◽

10.3390/en13184667 ◽

2020 ◽

Vol 13 (18) ◽

pp. 4667

Author(s):

Laurentiu Fara ◽

Irinela Chilibon ◽

Ørnulf Nordseth ◽

Dan Craciunescu ◽

Dan Savastru ◽

...

Keyword(s):

Solar Cells ◽

Solar Cell ◽

Reliability Analysis ◽

High Performance ◽

High Efficiency ◽

Absorber Layer ◽

Heterojunction Solar Cell ◽

Complex Investigation ◽

Heterojunction Solar Cells ◽

Conduction Band Offset

This study is aimed at increasing the performance and reliability of silicon-based heterojunction solar cells with advanced methods. This is achieved by a numerical electro-optical modeling and reliability analysis for such solar cells correlated with experimental analysis of the Cu2O absorber layer. It yields the optimization of a silicon tandem heterojunction solar cell based on a ZnO/Cu2O subcell and a c-Si bottom subcell using electro-optical numerical modeling. The buffer layer affinity and mobility together with a low conduction band offset for the heterojunction are discussed, as well as spectral properties of the device model. Experimental research of N-doped Cu2O thin films was dedicated to two main activities: (1) fabrication of specific samples by DC magnetron sputtering and (2) detailed characterization of the analyzed samples. This last investigation was based on advanced techniques: morphological (scanning electron microscopy—SEM and atomic force microscopy—AFM), structural (X-ray diffraction—XRD), and optical (spectroscopic ellipsometry—SE and Fourier-transform infrared spectroscopy—FTIR). This approach qualified the heterojunction solar cell based on cuprous oxide with nitrogen as an attractive candidate for high-performance solar devices. A reliability analysis based on Weibull statistical distribution establishes the degradation degree and failure rate of the studied solar cells under stress and under standard conditions.

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Deposition Technologies of High-Efficiency CIGS Solar Cells: Development of Two-Step and Co-Evaporation Processes

Crystals ◽

10.3390/cryst8070296 ◽

2018 ◽

Vol 8 (7) ◽

pp. 296 ◽

Cited By ~ 9

Author(s):

Chia-Hua Huang ◽

Wen-Jie Chuang ◽

Chun-Ping Lin ◽

Yueh-Lin Jan ◽

Yu-Chiu Shih

Keyword(s):

Solar Cells ◽

High Efficiency ◽

Open Circuit ◽

Film Properties ◽

Step Process ◽

Metal Precursors ◽

Stage Process ◽

Cigs Solar Cells ◽

Surface Morphologies ◽

The Given

The two-step process including the deposition of the metal precursors followed by heating the metal precursors in a vacuum environment of Se overpressure was employed for the preparation of Cu(In,Ga)Se2 (CIGS) films. The CIGS films selenized at the relatively high Se flow rate of 25 Å/s exhibited improved surface morphologies. The correlations among the two-step process parameters, film properties, and cell performance were studied. With the given selenization conditions, the efficiency of 12.5% for the fabricated CIGS solar cells was achieved. The features of co-evaporation processes including the single-stage, bi-layer, and three-stage process were discussed. The characteristics of the co-evaporated CIGS solar cells were presented. Not only the surface morphologies but also the grading bandgap structures were crucial to the improvement of the open-circuit voltage of the CIGS solar cells. Efficiencies of over 17% for the co-evaporated CIGS solar cells have been achieved. Furthermore, the critical factors and the mechanisms governing the performance of the CIGS solar cells were addressed.

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