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Lithography-Free Mesa Isolation of III–V Solar Cells Through Laser Ablation

Saenz, Theresa E. [National Renewable Energy Laboratory (NREL), Golden, CO (United States)] (ORCID:0000000277292051)·Curry, Daniel [University of Dayton, OH (United States)]·Gray, AJ [National Renewable Energy Laboratory (NREL), Golden, CO (United States)] (ORCID:0009000733937130)·Muzzio, Ryan [National Renewable Energy Laboratory (NREL), Golden, CO (United States)] (ORCID:0000000246699633)·Schall, Jackson W. [National Renewable Energy Laboratory (NREL), Golden, CO (United States)] (ORCID:000000024326639X)·Steiner, Myles A. [National Renewable Energy Laboratory (NREL), Golden, CO (United States)] (ORCID:0000000316439766)
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Abstract

Eliminating photolithography from solar cell processing is a significant opportunity for cost reduction for III-V solar cells. Here, in this work, we explore femtosecond laser ablation as an alternative to contact photolithography and wet chemical etching for mesa isolation. We demonstrate both GaAs and GaInP solar cells mesa-isolated by femtosecond laser ablation with minimal to no loss in solar cell performance. We show the best results with a 400 fs UV pulsed laser and a short clean-up etch that also serves as a contact layer removal etch.

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14 SOLAR ENERGY36 MATERIALS SCIENCEIII-V semiconductor materialslaser ablationoptoelectronic devicesphotovoltaic (PV) cellssemiconductor device manufacturesemiconductor thin films

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Saenz, Theresa E. [National Renewable Energy Laboratory (NREL), Golden, CO (United States)] (ORCID:0000000277292051), Curry, Daniel [University of Dayton, OH (United States)], Gray, AJ [National Renewable Energy Laboratory (NREL), Golden, CO (United States)] (ORCID:0009000733937130), Muzzio, Ryan [National Renewable Energy Laboratory (NREL), Golden, CO (United States)] (ORCID:0000000246699633), Schall, Jackson W. [National Renewable Energy Laboratory (NREL), Golden, CO (United States)] (ORCID:000000024326639X), Steiner, Myles A. [National Renewable Energy Laboratory (NREL), Golden, CO (United States)] (ORCID:0000000316439766). 2024-12-02. Lithography-Free Mesa Isolation of III–V Solar Cells Through Laser Ablation. https://doi.org/10.1109/jphotov.2024.3496484

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