US Startup Launches TOPCon Backside Copper Paste, Breaks Through Co-sintering Technology Bottleneck in Ambient Air
On February 19, 2026, US startup Bert Thin Films (BTF) announced the launch of its new-type copper paste product, CuBert™, specifically designed for the backside metallization of TOPCon solar cells. The technology achieved two major breakthroughs: first, it enables screen printing and sintering to be completed in ambient air without the need for inert gas protection; second, it allows for one-step co-firing with commercially available front-side silver paste, demonstrating strong process compatibility.