Thermally Stable Epiwafers for PV Applications
DOI:
https://doi.org/10.52825/siliconpv.v3i.2690Keywords:
Epiwafers, Boron-Diffusion, Thermal-StabilityAbstract
This work assesses the thermal stability of n-type Epiwafers after a boron diffusion based on the carrier lifetime measurements and photoluminescence images. The Epiwafers show a high bulk quality (iVoc > 735-745 mV) in their initial state after passivation with PECVD SiNx:H films. After a customized thermal budget for boron diffusion, the Epiwafers did not show any significant degradation, suggesting their high thermal stability. In contrast, some n-type Czochralski (nCz) silicon control samples degraded significantly (∆i Voc = -30 mV) due to the formation of ring defects during boron diffusion.
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Copyright (c) 2025 Rabin Basnet, Clemens Winter, Nicole Bein, Matthias Heilig, Frank Siebke, Giuliano Vescovi, Daniel Macdonald
This work is licensed under a Creative Commons Attribution 4.0 International License.
Accepted 2025-10-15
Published 2026-01-20