This work reports on state‐of‐the‐art silicon material characterization by calibrated photoluminescence (PL) imaging. PL imaging techniques allow for a characterization of a large variety of material properties, ranging from bulk and surface recombination properties of bare silicon ingots, to crystal structure, dopant concentration, and bulk lifetime of silicon wafers up to material limiting impurities. In combination with solar cell simulations, injection‐dependent PL imaging of processed wafers provides a method for determining the material's efficiency potential. In this contribution, we present two methods for imaging the concentration of interstitial iron at passivated silicon slices and at unpassivated silicon ingots. The latter is achieved by our latest progress in PL‐based charge carrier bulk lifetime measurements with highest sensitivity, giving access to the bulk recombination properties of the ingot. Additionally, we present an improved analysis of specific loss mechanisms in silicon based on de‐smeared injection‐dependent lifetime images of processed wafers, which is demonstrated on the example of the bulk‐related efficiency limitations in n ‐type high‐performance multicrystalline silicon. This latest progress rounds off the established techniques, enhancing the potential of PL‐based imaging techniques for a comprehensive assessment of silicon material quality, from limitations in bare silicon ingots to efficiency loss mechanisms in processed samples. Copyright © 2016 John Wiley & Sons, Ltd. The paper reports on recent advances in the field of photoluminescence imaging for material characterization. We present two new methods for imaging the concentration of interstitial iron, based on Calibrated photoluminescence imaging of passivated silicon slices Photoluminescence imaging of unpassivated silicon ingots calibrated by dynamic photoluminescence The third part of the paper focuses on an accurate determination of loss mechanisms in high‐performance multicrystalline silicon by an efficiency‐limiting bulk recombination analysis based on de‐smeared injection‐dependent photoluminescence images.
Material limits of multicrystalline silicon from state‐of‐the‐art photoluminescence imaging techniques
Progress in photovoltaics ; 25 , 7
2017
Article (Journal)
English
iron imaging , Efficiency , State of the art , Ingots , Iron , Service life assessment , Silicon , Silicon wafers , Carriers , Wafers , efficiency limits , modulated PL , multicrystalline silicon , Imaging , Imaging techniques , Crystal structure , Copyrights , photoluminescence imaging , Calibration , Impurities , Photoluminescence , Current carriers , Properties (attributes)
BKL: | 53.36 Energiedirektumwandler, elektrische Energiespeicher |
Dynamic photoluminescence lifetime imaging of multicrystalline silicon bricks
Online Contents | 2012
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