High Throughput Ion-Implantation for Silicon Solar Cells

AbstractIon implantation is a technique that has been demonstrated to improve solar cell efficiency and eliminate process steps in standard and advanced cell designs. Intevac has developed a high productivity, continuous flux ion implantation tool for solar cells. We demonstrate improved n-type emitters over POCl3 diffused emitters, and selective patterning capabilities. Additionally, it is shown that non-mass analyzed implantation provides similar performance as mass-analyzed implantation, yet at a much lower capital cost

Interactions Of Structural Defects With Metallic Impurities In Multicrystalline Silicon

Interactions between structural defects and metallic impurities were studied in multicrystalline silicon for solar cells applications. The objective was to gain insight into the relationship between solar cell processing, metallic impurity behavior and the resultant effect on material/device performance. With an intense synchrotron x-ray source, high sensitivity x-ray fluorescence measurements were utilized to determine impurity distributions with a spatial resolution of {approx} 1{micro}m. Diffusion length mapping and final solar cell characteristics gauged material/device performance. The materials were tested in both the as-grown state and after full solar cell processing. Iron and nickel metal impurities were located at structural defects in as-grown material, while after solar cell processing, both impurities were still observed in low performance regions. These results indicate that multicrystalline silicon solar cell performance is directly related to metal impurities which are not completely removed during typical processing treatments. A discussion of possible mechanisms for this incomplete removal is presented

Interactions of structural defects with metallic impurities in multicrystalline silicon

Interactions between structural defects and metallic impurities were studied in multicrystalline silicon for solar cells applications. The objective was to gain insight into the relationship between solar cell processing, metallic impurity behavior and the resultant effect on material/device performance. With an intense synchrotron x-ray source, high sensitivity x-ray fluorescence measurements were utilized to determine impurity distributions with a spatial resolution of {approx} 1{micro}m. Diffusion length mapping and final solar cell characteristics gauged material/device performance. The materials were tested in both the as-grown state and after full solar cell processing. Iron and nickel metal impurities were located at structural defects in as-grown material, while after solar cell processing, both impurities were still observed in low performance regions. These results indicate that multicrystalline silicon solar cell performance is directly related to metal impurities which are not completely removed during typical processing treatments. A discussion of possible mechanisms for this incomplete removal is presented

An agenda for creative practice in the new mobilities paradigm

Creative practices have made a standing contribution to mobilities research. We write this article as a collective of 25 scholars and practitioners to make a provocation: to further position creative mobilities research as a fundamental contribution and component in this field. The article explores how creative forms of research—whether in the form of artworks, exhibitions, performances, collaborations, and more—has been a foundational part of shaping the new mobilities paradigm, and continues to influence its methodological, epistemological, and ontological concerns. We tour through the interwoven history of art and mobilities research, outlining five central contributions that creativity brings. Through short vignettes of each author’s creative practice, we discuss how creativity has been key to the evolution and emergence of how mobilities research has expanded to global audiences of scholars, practitioners, and communities. The article concludes by highlighting the potency of the arts for lively and transdisciplinary pathways for future mobilities research in the uncertainties that lay ahead

Effect of thermal history on iron precipitation in crystalline silicon

We have studied the effect of thermal history on iron precipitation behavior in intentionally contaminated Czochralski silicon wafers that contain well-defined precipitation sites for iron, oxide precipitates. Iron precipitation was studied at a temperature range between 600°C and 700°C for various times. The results indicate that iron precipitation is strongly affected by the thermal history of the wafers. Our results also explain the disagreement observed previously in iron precipitation behavior at low temperature anneals. Finally, we discuss how the results can be applied to gettering in multicrystalline silicon.Peer reviewe