Heraeus pastes make it possible for cell manufacturers to lower the silver cost for front-side metallization to below US$0.01 per Wp.
One new product on show was the SOL9350 Series, designed for n-type cells with p(+) wafer surfaces. This series of pastes provides improved printability and makes it possible to achieve higher cells efficiencies. On bifacial n-type cells, the SOL9350 Series for p(+) wafer surfaces can be complemented with other Heraeus pastes, such as the SOL9610 Series or the lower silver SOL9300 Series. For back-side metallization, Heraeus offers low silver tabbing pastes with silver contents below 45%.
Heraeus also exhibited irs SOL9610 Series of front-side metallization pastes, which now have finer line resolution and improved contact to silicon wafers. The series of pastes has demonstrated cell efficiencies greater than 19.5% on standard p-type cells.
Heraeus says that its pastes have improved adhesion to both the front-side and back-side of solar cells. "In the R&D process, we focus on formulating pastes that advance both the electrical and mechanical performance of solar cells. Adhesion is considered a key factor in the mechanical performance of cells. During our paste development process, we will not sacrifice the mechanical performance and reliability of cells," said Dr Weiming Zhang, vice president of technology for the Heraeus photovoltaic business unit.