Key takeaways:
Maxwell targets 200 MW capacity per line for perovskite/HJT tandem production
The company’s direct copper plating solution is said to reduce metallization costs by over 30%
All core tools for Maxwell’s tandem and HJT lines are developed in-house, supporting integrated and scalable production
The adoption of silicon-perovskite tandem technology in the manufacturing roadmap and even product launches seem to be trending in the biggest PV trade shows in 2025. At the 18th SNEC PV Expo 2025, production equipment maker Maxwell presented its range of solar cell manufacturing technologies, with a particular focus on its ongoing developments in perovskite/HJT tandem cells, heterojunction (HJT) manufacturing lines, and direct copper plating solutions.
Perovskite/HJT Tandem: Moving Toward High-Efficiency Mass Production
Perovskite-on-silicon tandem cells have long been viewed as the next big step in boosting solar cell conversion efficiency. According to Maxwell, it began research and development (R&D) on perovskite/HJT tandem technology as early as 2019 and moved into developing equipment for mass production in 2023. By 2024, the company claims to have achieved key progress in lab-scale perovskite process tools, including prototype versions of large-area inkjet printers, evaporation systems, and atomic layer deposition (ALD) machines. These efforts are now focused on scaling up to pilot production at the 100 MW level.
Maxwell reports that between 2024 and early 2025, its full-textured tandem cells achieved third-party certifications of 31.50% efficiency from Germany’s Fraunhofer ISE and 34.02% from China’s National Photovoltaic Industry Metrology and Testing Center (NPVM).
To support commercialization, the company has developed a full production line for perovskite/HJT tandem cells with an annual capacity of 200 MW per line. Maxwell claims this integrated line can deliver 29% efficiency (with anti-reflective coating) and is built entirely from in-house equipment, from core machines to automation systems.
HJT Direct Copper Plating: A Cost-Focused Innovation
In addition to tandem technology, Maxwell also highlighted its progress in metallization techniques, particularly direct copper plating for HJT cells. Compared to traditional screen printing, the company says its seedless copper plating on the n-side of HJT cells reduces metallization costs by over 30%. Seedless copper plating involves direct deposition of copper without the need for a seed layer. Maxwell also claims this method contributes an efficiency gain of around 0.3%, with further cost reductions possible when combined with low-silver pastes.
The complete copper plating solution includes patterning and metallization steps using tools developed in-house, which, according to the company, offer high throughput, stable processes, and strong production yields – signaling readiness for scale-up.