LARGE AREA THIN FILM CADMIUM SULFIDE SOLAR CELL ARRAY INVESTIGATION

Laser scribing is an important manufacturing process used to reduce photocurrent and resistance losses and increase solar cell efficiency through the formation of serial interconnections in large-area solar cells. High-quality scribing is crucial since the main impediment to large-scale adoption of solar power is its high-production cost (price-per-watt) compared to competing energy sources such as wind and fossil fuels. In recent years, the use of glass-side laser scribing processes has led to increased scribe quality and solar cell efficiencies; however, defects introduced during the process such as thermal effect, microcracks, film delamination, and removal uncleanliness keep the modules from reaching their theoretical efficiencies. Moreover, limited numerical work has been performed in predicting thin-film laser removal processes. In this study, a nanosecond (ns) laser with a wavelength at 532 nm is employed for pattern 2 (P2) scribing on CdTe (cadmium telluride) based thin-film solar cells. The film removal mechanism and defects caused by laser-induced micro-explosion process are studied. The relationship between those defects, removal geometry, laser fluences, and scribing speeds are also investigated. Thermal and mechanical numerical models are developed to analyze the laser-induced spatiotemporal temperature and pressure responsible for film removal. The simulation can well-predict the film removal geometries, transparent conducting oxide (TCO) layer thermal damage, generation of microcracks, film delamination, and residual materials. The characterization of removal qualities will enable the process optimization and design required to enhance solar module efficiency.

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Recent advances in flexible perovskite solar cells

Chemical Communications ◽

10.1039/c5cc03666f ◽

2015 ◽

Vol 51 (79) ◽

pp. 14696-14707 ◽

Cited By ~ 62

Author(s):

B. Susrutha ◽

Lingamallu Giribabu ◽

Surya Prakash Singh

Keyword(s):

Thin Film ◽

Solar Cells ◽

Solar Cell ◽

Low Cost ◽

Perovskite Solar Cells ◽

Large Area ◽

Roll To Roll ◽

Recent Developments ◽

Reduced Dimension ◽

Thin Film Photovoltaics

Flexible thin-film photovoltaics facilitate the implementation of solar devices into portable, reduced dimension, and roll-to-roll modules. In this review, we describe recent developments in the fabrication of flexible perovskite solar cells that are low cost and highly efficient and can be used for the fabrication of large-area and lightweight solar cell devices.

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Thermochemical and Kinetic Aspects of Cadmium Telluride Solar Cell Processing

MRS Proceedings ◽

10.1557/proc-668-h1.6 ◽

2001 ◽

Vol 668 ◽

Cited By ~ 15

Author(s):

Brian E. McCandless

Keyword(s):

Thin Film ◽

Solar Cell ◽

Physical Vapor Deposition ◽

Film Deposition ◽

X Ray Diffraction ◽

Large Area ◽

Close Space Sublimation ◽

Processing Strategies ◽

Treatment Conditions ◽

Effect Of Treatment

ABSTRACTA chemical and kinetic basis underlying processing strategies for thin film polycrystalline CdTe/CdS solar cell fabrication is presented. The processing conditions employed for moderate and high conversion efficiency CdTe/CdS solar cells fall within a consistent framework based on temperature and concentration of CdCl2 and O2 species during film deposition or thermal treatment. Detailed microstructural and compositional results are compared for thin-film CdTe/CdS structures with CdTe deposited by physical vapor deposition, electrodeposition and close-space sublimation. X-ray diffraction coupled with a model for diffusion of CdS into CdTe is used to determine the effect of treatment conditions on bulk and grain boundary diffusion coefficients. The effects of CdS diffusion, oxides, recrystallization and grain growth with respect to device efficiency, stability and process control over large area are discussed.

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