Silicon Solar Cells: Structural Properties of Ag-Contacts/Si-Substrate

Lin, Ching-Hsi; Hsu, Shih-Peng; Hsu, Wei-Chih

doi:10.5772/19687

Cited by 9 publications

(9 citation statements)

References 14 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Although it can be argued that Ag has a very low diffusivity in Si, and that the front grid Ag firing step does not contaminate solar cells, in our case, the silver stays a longer time compared with typical firing times, and the silver layer completely covers the silicon sample surface, thus affecting the whole surface area. In fact, the dwelling time above 450°C in our lamp furnace is about four times longer than the typical firing times used for a commercial crystalline silicon solar cell [12], [20]. Furthermore, Chen et al [21] showed that silver diffusion in silicon occurs for temperatures above 450°C, leading to defect formation in the crystalline structure.…”

Section: Microstructurementioning

confidence: 95%

New Stress Activation Method for Kerfless Silicon Wafering Using Ag/Al and Epoxy Stress-Inducing Layers

Bellanger

Brito

Pera

et al. 2014

IEEE J. Photovoltaics

View full text Add to dashboard Cite

The SLIM-cut technique provides a way to obtain thin silicon foils without a standard sawing step, thus avoiding kerf losses. This process consists of three steps: depositing a stressinducing layer on top of the silicon surface; stress activation by heating and cooling, resulting in crack propagation in the silicon and detachment of a thin silicon layer; and a chemical cleaning to remove the stress-inducing layer. This paper describes a new stress activation method using Ag/Al and epoxy stress-inducing layers. The crack propagation is controlled along the sample length in order to avoid unwanted additional crack formation and interaction with other crack fronts. Silicon foils with thickness ranging between 50 and 130 μm were obtained with effective lifetimes between 1 and 81 μs.

show abstract

Section: Microstructurementioning

confidence: 95%

New Stress Activation Method for Kerfless Silicon Wafering Using Ag/Al and Epoxy Stress-Inducing Layers

Bellanger

Brito

Pera

et al. 2014

IEEE J. Photovoltaics

View full text Add to dashboard Cite

show abstract

“…Silver pastes with high conductivity, designed for rapid dry and spike firing, are commonly used for the standard screen printing process in the photovoltaic metallization [88][89][90][91]. A good silver paste should provide the final printed contacts featured with high line conductivity, low contact resistance to the underlying emitter, a high aspect ratio cross sectional profile and a good mechanical adhesion to the cell substrate surface.…”

Section: Silver Paste Preparationmentioning

confidence: 99%

“…The systematic combination of multiple inorganic and organic components with uniform dispersion in the paste distinguish the features of one from another. Nevertheless, the fundamentally functional constituents are relatively similar [90]. The organic solvent serves as the temporary carrier, which will be evaporated and decomposed during the drying/firing process and leave only inorganic components like silver powder and glass frit on the wafer.…”

Section: Silver Paste Preparationmentioning

confidence: 99%

Desarrollo de procesos para formación de contactos con láser para módulos thin film CIGS para aplicaciones fotovoltaicas

Chen¹

View full text Add to dashboard Cite

“…It also is very easy to use the paste to connect multiple modules together, whether or not the actual contacts are made with the silver paste. (Bowden, 2008;Lin, 2011;Lindholm, 1982;Savage, 2013;Seiward, 2011) Finally, the form of the solar cell array is dependent on the available technology.…”

Section: Factors For Considerationmentioning

confidence: 99%

“…Then a squeegee applies a thick layer of silver paste to the stencil, which is then lifted off, leaving the correct pattern on the solar cell. Once the stencil is removed, the solar cell is put in an oven, which melts the solder and allows it to solidify when cooled (Lin, 2011).…”

Section: Thicker Traces and Trace Materialsmentioning

confidence: 99%

Constructing and Optimizing a Single Wafer Solar Cell Array in the Microfabrication Lab at California Polytechnic State University at San Luis Obispo

Marstell¹

View full text Add to dashboard Cite

This study contains research that details all aspects of how solar cells work. It also details three years' worth of studies at California Polytechnic State University (Cal Poly) that attempt to fabricate a solar cell array on a single wafer.Two tests were carried out that will help determine the optimal attributes of the solar cells. The first compared a solar cell made on a 10 µm thick silicon on insulator (SOI) wafer to solar cells made with the exact same masks on a 500 µm thick wafer. The thicker solar cell had 2.5 times the maximum power as the SOI solar cell. Aspects of the solar cell that would need to be improved are: increase thickness to between 70-100 µm from the SOI thickness, texture the front surface, add a passivation layer on the front surface, decrease the contact resistance for the metal electrodes, and add in a rear reflector. The next test was all about analyzing the metal contacts and interconnects. Page vTen gold-silver filled epoxy-gold bonds were constructed and measured ten times each, giving a grand mean between 10 and 11 Ω. Another short test was run with a commercial solar cell to characterize the change in power based on the series resistance. It was discovered that the both the epoxy and the gold add too much to the resistance. To fix this, a silver solder-like paste and a thicker contact metal should be used. There is also a derivation that details the design of a top contact layer that optimizes the finger spacing and finger width based on other solar cell factors. With the materials available at Cal Poly, a solar cell array can be fabricated on a single wafer. When accounting for the materials and processes available to the scientific community as a whole, a very effective and efficient solar cell can be fabricated.

show abstract

Silicon Solar Cells: Structural Properties of Ag-Contacts/Si-Substrate

Cited by 9 publications

References 14 publications

New Stress Activation Method for Kerfless Silicon Wafering Using Ag/Al and Epoxy Stress-Inducing Layers

New Stress Activation Method for Kerfless Silicon Wafering Using Ag/Al and Epoxy Stress-Inducing Layers

Desarrollo de procesos para formación de contactos con láser para módulos thin film CIGS para aplicaciones fotovoltaicas

Constructing and Optimizing a Single Wafer Solar Cell Array in the Microfabrication Lab at California Polytechnic State University at San Luis Obispo

Contact Info

Product

Resources

About