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DOE OSTI · 3017156

Coupled CVD and Float Zone Reactor for Lower Cost, Higher Efficiency Si Boules (Final Technical Report)

Schulte, Kevin [National Laboratory of the Rockies (NLR), Golden, CO (United States)] (ORCID:0000000342736254)
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Abstract

This project modeled a new type of photovoltaic (PV) Si production reactor with the promise to reduce the cost, increase the efficiency, and reduce the energy required to manufacture Si wafers. The production of photovoltaic (PV) grade Si is well established, based on the pulling of single crystalline Si boules from polycrystalline Si created from trichlorosilane using the Siemens process. However, these processes are very energy intensive, and manufacturing of PV Si occurs almost entirely in China. To disrupt this paradigm and on-shore production of this critical material and provide benefits to the public, a substantial technological leap is required to move past incumbent technology. This study evaluated a new float zone chemical vapor deposition (Fz-CVD) concept in which trichlorosilane (TCS), the feedstock for polysilicon in the Siemens process, is injected directly into a float zone crystallizer to continuously deposit the feed rod for the boule pulling process through a combination of multiphysics modeling and technoeconomic analysis.

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14 SOLAR ENERGYchemical vapor depositioncrystallizationfloat zonemodelingphotovoltaicsPVsilicon

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Schulte, Kevin [National Laboratory of the Rockies (NLR), Golden, CO (United States)] (ORCID:0000000342736254). 2026-02-02. Coupled CVD and Float Zone Reactor for Lower Cost, Higher Efficiency Si Boules (Final Technical Report). https://doi.org/10.2172/3017156

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