Nanometer-scale metal precipitates in multicrystalline silicon solar cells
- and others
In this study, we have utilized characterization methods to identify the nature of metal impurity precipitates in low performance regions of multicrystalline silicon solar cells. Specifically, we have utilized synchrotron-based x-ray fluorescence and x-ray absorption spectromicroscopy to study the elemental and chemical nature of these impurity precipitates, respectively. We have detected nanometer-scale precipitates of Fe, Cr, Ni, Cu, and Au in multicrystalline silicon materials from a variety of solar cell manufacturers. Additionally, we have obtained a direct correlation between the impurity precipitates and regions of low light-induced current, providing direct proof that metal impurities play a significant role in the performance of multicrystalline silicon solar cells. Furthermore, we have identified the chemical state of iron precipitates in the low-performance regions. These results indicate that the iron precipitates are in the form of oxide or silicate compound. These compounds are highly stable and cannot be removed with standard silicon processing, indicating remediation efforts via impurity removal need to be improved. Future improvements to multicrystalline silicon solar cell performance can be best obtained by inhibiting oxygen and metal impurity introduction as well as modifying thermal treatments during crystal growth to avoid oxide or silicate formation.
- Sponsoring Organization:
- (US)
- OSTI ID:
- 40204940
- Journal Information:
- Journal of Applied Physics, Vol. 89, Issue 8; Other Information: DOI: 10.1063/1.1330552; Othernumber: JAPIAU000089000008004282000001; 021102JAP; PBD: 15 Apr 2001; ISSN 0021-8979
- Publisher:
- The American Physical Society
- Country of Publication:
- United States
- Language:
- English
Similar Records
Interactions of structural defects with metallic impurities in multicrystalline silicon
Synchrotron-based investigations of the nature and impact of ironcontamination in multicrystalline silicon solar cell materials