High Temperature Copper Metallization: Demand, Hurdles and Reliability

Dharmadasa, Ruvini; Williams, Dustin; Elmer, Kevin; Druffel, Thad; Nemeth, William; Johnston, Steve (ORCID:0000000333088267); Stradins, Paul

doi:10.1109/pvsc57443.2024.10749130

DOE OSTI · 2499738

High Temperature Copper Metallization: Demand, Hurdles and Reliability

Dharmadasa, Ruvini·Williams, Dustin·Elmer, Kevin·Druffel, Thad·Nemeth, William·Johnston, Steve (ORCID:0000000333088267)·Stradins, Paul

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Abstract

As newer cells structures come online, the pressing need to replace silver in the metallization pastes has renewed interest in alternative technologies employing base metals. Copper typically leads the charge with its abundance and lower cost but has faced numerous obstacles from relatively higher oxidation and diffusion rates which can damage the lifetime of the devices. In this study, a low-cost alternative to silver metallization pastes has been shown on PERC cells. The screen printable copper paste can be fired in air at temperatures >500 degrees C, and the impact of processing conditions and equipment on the performance and reliability of 274 cm2 cells have been evaluated. Through damp heat testing of micro-modules using 16 cm2 cells, routes that can lead to both the failure and success of durable contacts have been demonstrated.

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copper electric potential metallization optimization oxidation performance evaluation photovoltaic systems pressing reliability silver SOLAR ENERGY

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Dharmadasa, Ruvini, Williams, Dustin, Elmer, Kevin, Druffel, Thad, Nemeth, William, Johnston, Steve (ORCID:0000000333088267), Stradins, Paul. 2024-11-15. High Temperature Copper Metallization: Demand, Hurdles and Reliability. https://doi.org/10.1109/pvsc57443.2024.10749130

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