Impact of Impurities From Crucible and Coating on mc-Silicon Quality-the Example of Iron and Cobalt

被引:61
作者
Schubert, Martin C. [1 ]
Schoen, Jonas [1 ]
Schindler, Florian [1 ,2 ]
Kwapil, Wolfram [1 ,2 ]
Abdollahinia, Alireza [1 ,2 ]
Michl, Bernhard [1 ]
Riepe, Stephan [1 ]
Schmid, Claudia [1 ]
Schumann, Mark [1 ]
Meyer, Sylke [3 ]
Warta, Wilhelm [1 ]
机构
[1] Fraunhofer Inst Solar Energy Syst, Freiburg, Germany
[2] Freiburg Mat Res Ctr FMF, Freiburg, Germany
[3] Fraunhofer Ctr Silicon Photovolta, Halle, Germany
来源
IEEE JOURNAL OF PHOTOVOLTAICS | 2013年 / 3卷 / 04期
关键词
Crucible; iron; silicon; simulation; vertical gradient freeze (VGF); MULTICRYSTALLINE SILICON; DIFFUSION;
D O I
10.1109/JPHOTOV.2013.2279116
中图分类号
TE [石油、天然气工业]; TK [能源与动力工程];
学科分类号
0807 ; 0820 ;
摘要
The aim of this paper is to analyze the limiting role of crucible and coating impurities on material quality of multicrystalline silicon. Both solid body diffusion and diffusion into the silicon melt are considered in this study. Two ingots of size G1 have been analyzed. One of them was crystallized in a standard crucible, whereas the other was crystallized in a quartz crucible of very high purity. Focus is put on iron and cobalt as examples of typical impurity species. Iron was found in large concentrations in standard crucibles, and cobalt was proven to be a suitable marker impurity that is mainly found in the coating. Inductively coupled plasma mass spectroscopy data are exploited for the determination of impurity concentrations in crucible, coating, and within the crystal. With higher sensitivity for low concentration, PL imaging is applied for carrier lifetime and interstitial iron concentration measurements. The different findings are compared with modeling results of iron and cobalt in-diffusion by Sentaurus Process. The analysis of silicon wafers before and after gettering steps enable a quantification of impurity-limiting cell efficiency potential. Conclusions about the role of impurities from coated crucibles in large-scale crystallization are deduced.
引用
收藏
页码:1250 / 1258
页数:9
相关论文
共 35 条
[11]   Gettering in silicon-on-insulator wafers:: experimental studies and modelling [J].
Istratov, AA ;
Väinölä, H ;
Huber, W ;
Weber, ER .
SEMICONDUCTOR SCIENCE AND TECHNOLOGY, 2005, 20 (06) :568-575
[12]   Iron and its complexes in silicon [J].
Istratov, AA ;
Hieslmair, H ;
Weber, ER .
APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING, 1999, 69 (01) :13-44
[13]   Influence of crucible and coating quality on the properties of multicrystalline silicon for solar cells [J].
Kvande, R. ;
Arnberg, L. ;
Martin, C. .
JOURNAL OF CRYSTAL GROWTH, 2009, 311 (03) :765-768
[14]   Imaging interstitial iron concentrations in boron-doped crystalline silicon using photoluminescence [J].
Macdonald, D. ;
Tan, J. ;
Trupke, T. .
JOURNAL OF APPLIED PHYSICS, 2008, 103 (07)
[15]   DIFFUSION OF METALS IN SILICON DIOXIDE [J].
MCBRAYER, JD ;
SWANSON, RM ;
SIGMON, TW .
JOURNAL OF THE ELECTROCHEMICAL SOCIETY, 1986, 133 (06) :1242-1246
[16]   Efficiency limiting bulk recombination in multicrystalline silicon solar cells [J].
Michl, B. ;
Ruediger, M. ;
Giesecke, J. A. ;
Hermle, M. ;
Warta, W. ;
Schubert, M. C. .
SOLAR ENERGY MATERIALS AND SOLAR CELLS, 2012, 98 :441-447
[17]  
Michl B., 2012, J PHOTOVOLTAICS, V3, P635
[18]  
Montaser A.:., 1998, INDUCTIVELY COUPLED
[19]   Origin of the Low Carrier Lifetime Edge Zone in Multicrystalline PV Silicon [J].
Naerland, Tine Uberg ;
Arnberg, Lars ;
Holt, Arve .
PROGRESS IN PHOTOVOLTAICS, 2009, 17 (05) :289-296
[20]   Silicon nitride coating and crucible - Effects of using upgraded materials in the casting of multicrystalline silicon ingots [J].
Olsen, E. ;
Ovrelid, E. J. .
PROGRESS IN PHOTOVOLTAICS, 2008, 16 (02) :93-100