Optimizing phosphorus diffusion for photovoltaic applications: Peak doping, inactive phosphorus, gettering, and contact formation
The phosphosilicate glass (PSG), fabricated by tube furnace diffusion using a POCl₃ source, is widely used as a dopant source in the manufacturing of crystalline silicon solar cells. Although it has been a widely addressed research topic for a long time, there is still lack of a comprehensive unders...
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American Institute of Physics (AIP)
2018
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| Online Access: | http://hdl.handle.net/1721.1/118983 https://orcid.org/0000-0001-9352-8741 https://orcid.org/0000-0001-8345-4937 |
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| author | Dastgheib-Shirazi, Amir Min, Byungsul Steyer, Michael Hahn, Giso del Cañizo, Carlos Altermatt, Pietro P. Wagner, Hannes Morishige, Ashley Elizabeth Buonassisi, Anthony |
| author2 | Massachusetts Institute of Technology. Department of Mechanical Engineering |
| author_facet | Massachusetts Institute of Technology. Department of Mechanical Engineering Dastgheib-Shirazi, Amir Min, Byungsul Steyer, Michael Hahn, Giso del Cañizo, Carlos Altermatt, Pietro P. Wagner, Hannes Morishige, Ashley Elizabeth Buonassisi, Anthony |
| author_sort | Dastgheib-Shirazi, Amir |
| collection | MIT |
| description | The phosphosilicate glass (PSG), fabricated by tube furnace diffusion using a POCl₃ source, is widely used as a dopant source in the manufacturing of crystalline silicon solar cells. Although it has been a widely addressed research topic for a long time, there is still lack of a comprehensive understanding of aspects such as the growth, the chemical composition, possible phosphorus depletion, the resulting in-diffused phosphorus profiles, the gettering behavior in silicon, and finally the metal-contact formation. This paper addresses these different aspects simultaneously to further optimize process conditions for photovoltaic applications. To do so, a wide range of experimental data is used and combined with device and process simulations, leading to a more comprehensive interpretation. The results show that slight changes in the PSG process conditions can produce high-quality emitters. It is predicted that PSG processes at 860 °C for 60 min in combination with an etch-back and laser doping from PSG layer results in high-quality emitters with a peak dopant density N[subscript peak] = 8.0 × 10¹⁸cm⁻³ and a junction depth dj= 0.4 μm, resulting in a sheet resistivity ρ[subscript sh] = 380 Ω/sq and a saturation current-density J₀below 10 fA/cm². With these properties, the POCl₃ process can compete with ion implantation or doped oxide approaches. |
| first_indexed | 2024-09-23T09:49:58Z |
| format | Article |
| id | mit-1721.1/118983 |
| institution | Massachusetts Institute of Technology |
| last_indexed | 2024-09-23T09:49:58Z |
| publishDate | 2018 |
| publisher | American Institute of Physics (AIP) |
| record_format | dspace |
| spelling | mit-1721.1/1189832022-09-30T17:07:54Z Optimizing phosphorus diffusion for photovoltaic applications: Peak doping, inactive phosphorus, gettering, and contact formation Dastgheib-Shirazi, Amir Min, Byungsul Steyer, Michael Hahn, Giso del Cañizo, Carlos Altermatt, Pietro P. Wagner, Hannes Morishige, Ashley Elizabeth Buonassisi, Anthony Massachusetts Institute of Technology. Department of Mechanical Engineering Wagner, Hannes Morishige, Ashley Elizabeth Buonassisi, Anthony The phosphosilicate glass (PSG), fabricated by tube furnace diffusion using a POCl₃ source, is widely used as a dopant source in the manufacturing of crystalline silicon solar cells. Although it has been a widely addressed research topic for a long time, there is still lack of a comprehensive understanding of aspects such as the growth, the chemical composition, possible phosphorus depletion, the resulting in-diffused phosphorus profiles, the gettering behavior in silicon, and finally the metal-contact formation. This paper addresses these different aspects simultaneously to further optimize process conditions for photovoltaic applications. To do so, a wide range of experimental data is used and combined with device and process simulations, leading to a more comprehensive interpretation. The results show that slight changes in the PSG process conditions can produce high-quality emitters. It is predicted that PSG processes at 860 °C for 60 min in combination with an etch-back and laser doping from PSG layer results in high-quality emitters with a peak dopant density N[subscript peak] = 8.0 × 10¹⁸cm⁻³ and a junction depth dj= 0.4 μm, resulting in a sheet resistivity ρ[subscript sh] = 380 Ω/sq and a saturation current-density J₀below 10 fA/cm². With these properties, the POCl₃ process can compete with ion implantation or doped oxide approaches. National Science Foundation (U.S.) (Contract EEC-1041895) United States. Department of Energy (Contract EEC-1041895) United States. Department of Energy (Award DE-EE0006335) 2018-11-09T19:44:14Z 2018-11-09T19:44:14Z 2016-05 2015-11 2018-11-02T15:01:19Z Article http://purl.org/eprint/type/JournalArticle 0021-8979 1089-7550 http://hdl.handle.net/1721.1/118983 Wagner, Hannes et al. “Optimizing Phosphorus Diffusion for Photovoltaic Applications: Peak Doping, Inactive Phosphorus, Gettering, and Contact Formation.” Journal of Applied Physics 119, 18 (May 2016): 185704 © 2016 Author(s) https://orcid.org/0000-0001-9352-8741 https://orcid.org/0000-0001-8345-4937 http://dx.doi.org/10.1063/1.4949326 Journal of Applied Physics Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use. application/pdf American Institute of Physics (AIP) Other repository |
| spellingShingle | Dastgheib-Shirazi, Amir Min, Byungsul Steyer, Michael Hahn, Giso del Cañizo, Carlos Altermatt, Pietro P. Wagner, Hannes Morishige, Ashley Elizabeth Buonassisi, Anthony Optimizing phosphorus diffusion for photovoltaic applications: Peak doping, inactive phosphorus, gettering, and contact formation |
| title | Optimizing phosphorus diffusion for photovoltaic applications: Peak doping, inactive phosphorus, gettering, and contact formation |
| title_full | Optimizing phosphorus diffusion for photovoltaic applications: Peak doping, inactive phosphorus, gettering, and contact formation |
| title_fullStr | Optimizing phosphorus diffusion for photovoltaic applications: Peak doping, inactive phosphorus, gettering, and contact formation |
| title_full_unstemmed | Optimizing phosphorus diffusion for photovoltaic applications: Peak doping, inactive phosphorus, gettering, and contact formation |
| title_short | Optimizing phosphorus diffusion for photovoltaic applications: Peak doping, inactive phosphorus, gettering, and contact formation |
| title_sort | optimizing phosphorus diffusion for photovoltaic applications peak doping inactive phosphorus gettering and contact formation |
| url | http://hdl.handle.net/1721.1/118983 https://orcid.org/0000-0001-9352-8741 https://orcid.org/0000-0001-8345-4937 |
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