Research Article
Design Window for SHJ Cells: Joint Impact of Base Thickness and Doping Under AM1.5G
Issue:
Volume 13, Issue 4, December 2025
Pages:
158-170
Received:
9 October 2025
Accepted:
17 October 2025
Published:
31 October 2025
DOI:
10.11648/j.ajee.20251304.11
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Abstract: We numerically map the joint impact of base thickness (e) and donor density (ND) on silicon heterojunction (SHJ) cells under AM1.5G using SILVACO ATLAS (drift–diffusion with SRH/Auger and field/concentration dependent mobilities). Optics is treated by 2D specular ray tracing (no texturing), so results constitute a conservative baseline at small e. To isolate e and ND, the a Si:H/c Si interface is held fixed across parameter sweeps. We identify an absorption–collection trade off: Jsc increases from thin to moderate e and then saturates or declines; Voc decreases with increasing e and high ND due to enhanced recombination. The fill factor peaks at small e under low to moderate ND. Efficiency exhibits a robust optimum at moderate thickness (e.g., e ≈ 120-160μm) and intermediate ND, whereas heavy doping shifts the optimum but ultimately degrades Voc/FF via Auger (and, in extended models, band gap narrowing). From a design standpoint, we delineate a practical window that balances resistivity and recombination while avoiding heavy doping. Limitations: absence of light trapping and fixed interface, mean our absolute metrics are conservative, but trends and optima are robust. Planned extensions include Lambertian/textured optics, interface sweeps, and calibrated BGN/contact models to raise absolute values without altering the identified trade offs.
Abstract: We numerically map the joint impact of base thickness (e) and donor density (ND) on silicon heterojunction (SHJ) cells under AM1.5G using SILVACO ATLAS (drift–diffusion with SRH/Auger and field/concentration dependent mobilities). Optics is treated by 2D specular ray tracing (no texturing), so results constitute a conservative baseline at small e. ...
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,
Aly Toure
