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Light-Induced Boron-Oxygen Recombination Centres in Silicon: Understanding their Formation and Elimination
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Iron Management in Multicrystalline Silicon through Predictive Simulation: Point Defects, Precipitates, and Structural Defect Interactions
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External and Internal Gettering of Interstitial Iron in Silicon for Solar Cells
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Precipitation of Interstitial Iron in Multicrystalline Silicon
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Direct Observation of Carrier Trapping Processes on Fe Impurities in mc-Si Solar Cells
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On the Trade-Off between Industrially Feasible Silicon Surface Preconditioning Prior to Interface Passivation and Iron Contaminant Removal Effectiveness
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Defect Generation and Propagation in Mc-Si Ingots: Influence on the Performance of Solar Cells
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Characterisation of Dislocation-Content in Multicrystalline-Silicon Wafers
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HomeSolid State PhenomenaSolid State Phenomena Vols. 205-206Iron Management in Multicrystalline Silicon...

Iron Management in Multicrystalline Silicon through Predictive Simulation: Point Defects, Precipitates, and Structural Defect Interactions

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Abstract:

In multicrystalline silicon for photovoltaic applications, high concentrations of iron are usually found, which deteriorate material performance. Due to the limited solubility of iron in silicon, only a small fraction of the total iron concentration is present as interstitial solute atoms while the vast majority is present as iron silicide precipates. The concentration of iron interstitials can be effectively reduced during phosphorus diffusion gettering (PDG), but this strongly depends on the size and density of iron precipitates, which partly dissolve during high-temperature processing. The distribution of precipitated iron varies along the height of a mc-Si ingot and is not significantly reduced during standard PDG steps. However, the removal of both iron interstitials and precipitates can be enhanced by controlling their kinetics through carefully engineered time-temperature profiles, guided by simulations.

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Solid State Phenomena (Volumes 205-206)

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15-25

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https://doi.org/10.4028/www.scientific.net/SSP.205-206.15

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Online since:

October 2013

Authors:

Jasmin Hofstetter, David P. Fenning, Douglas M. Powell, Ashley E. Morishige, Tonio Buonassisi

Keywords:

Gettering, Interstitials, Iron, Multicrystalline Silicon, Precipitate

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