Heraeus Photovoltaics, the worldwide leading supplier of metallization solutions to the PV industry, announced the launch of two advanced PERC metallization paste series at the SNEC 2016 in Shanghai. The new products, SOL9631, a low-temperature front-side paste for PERC, and SOL326, a low-activity back-side silver tabbing paste, are offered as part of a PERC package. The pastes enable customers and partners of Heraeus to produce PERC cells with significant improvement on both efficiency and adhesion.
“With the SOL9631 and the SOL326 as our newest additions to our portfolio of innovative metallization products, customers can achieve higher PERC cell efficiencies, reduced LID and improved module reliability,” noted Dr. Weiming Zhang, Senior Vice President Innovation, Heraeus Photovoltaics.“This proves our strong commitment to continuously provide our customers and partners with the most advanced metallization pastes, helping them to realize significant performance improvements.” He further emphasizes Heraeus’ strong capability, experience and expertise of in-house glass frit development and production, the key enabler for the excellent performance of its metallization paste products.
The SOL9631 front-side paste series features a unique brand-new glass chemistry, exclusively developed and manufactured by Heraeus, combined with the latest breakthrough in organic vehicle system for ultra-fine-line printing. The paste can be fired at low temperatures, making it specifically suitable for PERC solar cells. The densified microstructure of the fired finger, including the Ag-Silicon interface, enhances adhesion, grid resistivity and solderability. Beyond significantly improving the reliability performance of PERC-solar cells and the later module, light-introduced-degradation (LID) loss is reduced to be similar as a normal P-type module. Furthermore the SOL9631 series is perfectly tailored for Ultra-fine-line printability. It supports a finger geometry that can print defect-free through a less than 30 µm screen opening in high throughput mass production, resulting in an efficiency gain through reduced optical shading and less contact area.
Heraeus’ new low-activity SOL326 PERC back side tabbing paste series contains a specific glass chemistry, imparting controlled reaction between Ag paste and the dielectric layer. In combination with newly developed paste additives, this results in less fire-through/penetration into the passivation and better protects the emitter during the metallization process. With its unique properties, the SOL326 series enables to increase cell efficiencies with over 20%, higher aged adhesion and improved Voc as well as higher module reliability.