Heraeus unveils HeraGlaze coating and three new metallization pastes at PV Expo

Heraeus, the German-headquartered specialist in metallization pastes for the solar PV industry, has introduced three new products at the PV Expo 2017 event that began today in Tokyo, Japan.

Additionally, the firm also chose the occasion of the show’s opening day to roll out its HeraGlaze coating, which is a high-purity diffusion barrier coating for enhanced crucible performance in wafer production.

The three new metallization pastes promise higher efficiency gains for various PV cells, including established technologies such as PERC, multi and mono, as well as for emerging cell architectures such as heterojunction (HJT) and organic (OPV) cells.

The SOL9641B has been developed for PERC and improved performance on ultra-low dope emitters (ULDE), promising efficiency gains of up to 0.2%, Heraeus claims. Its SOL570 metallization paste, meanwhile, is a low temperature paste that utilizes silver powder development and organic design to offer improved adhesion on HJT cells and efficiency gains of up to 0.05%.

The third metallization paste, the SOL9641AX/BX, has been developed for zero degree mesh printing screens and boasts a knotless screen that allows finer finger printing, delivering better efficiencies and greater cost advantage, Hereaus says.

“This is a new technology, and to leverage it takes a specific design formula, a paste we call X,” Weiming Zhang, SVP production innovation at Heraeus told pv magazine. “The benefit is it can enable customers to get a finer line screen opening, the line can be narrower, and because there is no knot, it helps the paste transfer.”

Zhang spoke of Heraeus’s continued admiration for the demands on quality that the Japanese market continues to place, which is why the German firm chose the PV Expo event to roll out its new pastes and HeraGlaze coating.

“Japan is a leading market in terms of renewable energy consumption, innovation and high efficiency applications,” Zhang said. “Demand is always for good quality, and we are proud to have cornered a 60% share of the Japanese PV paste market over the past 12 years.”

The HeraGlaze coating, also unveiled today, can increase wafer yield by 4% and cell efficiency by 0.1%. Based on an estimated 50 GW wafer production capacity globally, Heraeus calculates that it can deliver an additional 2 GW per year with HeraGlaze, without increasing actual wafer production capacity.

Effective at the initial solar cell manufacturing process during the production of silicon ingots, HeraGlaze is a slurry coating that acts as a barrier, preventing thermally induced impurities such as iron to transfer from the crucible to the silicon.

“HeraGlaze… is our first product beyond solar cell metallization and another R&D landmark, which enables our customers to realize further efficiency gains,” said Heraeus Photovoltaics president Andreas Liebheit.