On February 19, 2026, American startup Bert Thin Films (BTF) launched its new copper paste product, CuBert™, specifically designed for the backside metallization of TOPCon solar cells. This technology marks a significant advancement, enabling the screen printing and firing processes to be completed in an atmospheric air environment without the need for inert gas protection. It also supports one-step co-firing with commonly available front-side silver pastes on the market, demonstrating excellent process compatibility.

The introduction of TOPCon backside copper paste technology brings new possibilities to solar cell manufacturing. In traditional processes, metallization steps typically require strictly controlled atmospheres, whereas BTF's innovative solution simplifies the production flow, reducing equipment complexity and operational costs. The achievement of atmospheric air co-firing lessens dependence on external gas supply, contributing to improved production efficiency and environmental friendliness.

The application of the CuBert™ copper paste product is expected to facilitate the wider adoption of TOPCon cell technology. Compared to silver paste, copper material costs are lower, and its conductive properties are excellent, giving it a potential advantage in backside metallization. The compatibility with one-step co-firing processes means manufacturers can more flexibly integrate existing production lines, accelerating the pace of technological iteration.

This breakthrough technology, developed by the US startup Bert Thin Films, showcases its research capabilities in the solar field. The company stated that the launch of the CuBert™ copper paste is based on a deep understanding of the TOPCon cell structure, aiming to address technical challenges in the metallization stage. In the future, this product is likely to be promoted in the global solar market, supporting the development of clean energy.