**4. Conclusions**

For the first time, we propose a coupling device scheme for the preparation of electronic polysilicon by the modified Siemens method and carried out modeling and prediction work on the coupled furnaces based on numerical methods. The distribution of physical fields in the chamber and the uniformity of deposition conditions on the surface of the silicon rods in different base plate designs of the single furnace were analyzed. Based on a large flow rate scheme, the coupled furnaces' silicon rod deposition process was modeled, as well as connecting pipelines and structures. By increasing the flow rate by about 2 times, the coupling mode improves the utilization of raw materials by 17.5% and the deposition rate by 44.9%, while the deposition quality is approximately unchanged. This work provides a new idea for optimizing the deposition characteristics and preparation process of electronic-grade polysilicon at a low cost.

**Author Contributions:** Conceptualization, S.Z.; methodology, S.Z. and H.F.; software, J.H.; validation, G.F.; formal analysis, H.F. and G.F.; investigation, T.L.; resources, J.H.; data curation, S.Z.; writing original draft preparation, S.Z.; writing—review and editing, L.Z.; visualization, H.F. and J.H.; supervision, L.Z. and T.L.; project administration, T.L.; funding acquisition, L.Z. All authors have read and agreed to the published version of the manuscript.

**Funding:** This research was funded by [Major Scientific and Technological Achievements Transformation Projects of Heilongjiang Province of China] grant number [CG20A008], [Natural Science Foundation of Heilongjiang Province] grant number [JQ2019E003], [2021 Harbin Science and Technology Special Plan Project] grant number [2021ZSZZGH10]. The APC was funded by [Major Scientific and Technological Achievements Transformation Projects of Heilongjiang Province of China].

**Institutional Review Board Statement:** Not applicable.

**Informed Consent Statement:** Not applicable.

**Acknowledgments:** The authors thank Soft-Impact China (Harbin), Ltd. Harbin. for its support in simulation content.

**Conflicts of Interest:** The authors declare no conflict of interest.

#### **References**


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