POCl₃ diffusion for industrial Si solar cell emitter formation

Abstract

POCl₃ diffusion is currently the de facto standard method for industrial n-type emitter fabrication. In this study, we present the impact of the following processing parameters on emitter formation and electrical performance: deposition gas flow ratio, drive-in temperature and duration, drive-in O₂ flow rate, and thermal oxidation temperature. By showing their influence on the emitter doping profile and recombination activity, we provide an overall strategy for improving industrial POCl₃ tube diffused emitters.

Graphical abstract

Keywords

POCl₃ diffusion / emitter recombination / oxidation / silicon

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Acknowledgments

The authors would like to acknowledge Dr. Nino Borojevic, Dr. Ly Mai and MAiA processing team who assisted with wafer processing. This Program has been supported by the Australian Government through the Australian Renewable Energy Agency (ARENA) and the Australian Centre for Advanced Photovoltaics (ACAP). The views expressed herein are not necessarily the views of the Australian Government, and the Australian Government does not accept responsibility for any information or advice contained herein. The authors would like to thank the commercial partners of the ARENA 1-A060 project for their funding support for this work.

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