The Heraeus Photovoltaics Business Unit has launched two new high efficiency front-side metallization pastes for standard to ultra-lightly doped emitter cells – the SOL9620 Series and SOL9621 Series.
PV manufacturers of conventional c-Si solar cells take different approaches to cell designs and fabrication processes, which result in varying sheet resistances. The challenge is to source the right metallization paste suitable to the respective cell type and individual manufacturing processes.
The SOL9620 Series and SOL9621 Series enables cell manufacturers to further improve their c-Si cells’ conversion efficiencies to an industry-leading level. By using these new pastes, the company has claimed that customers have confirmed efficiency improvements that ranged between 0.05% and 0.20% absolute on lightly doped emitter [90 – 100 Ω/sq.] wafers, relative to the best commercially available front-side pastes. Even greater gains have been achieved on ultra lightly doped emitter [110 Ω/sq.] wafers, where the paste unfolds its peak performance. The SOL9620 Series and SOL9621 Series of pastes are able to provide improved contact on lightly doped emitters [LDE]. The reduced contact resistance on LDE und ULDE wafers helps yielding increased voltage and higher cell efficiencies.
Front-side metallization pastes for standard to ultra-lightly doped emitter cells.
The SOL9620 Series is designed for ultra-lightly doped emitters [ULDE], with surface doping concentrations down to 1xE20/cm3. “The SOL9620 Series also has the ability to be fired at a peak temperature 15 K less than standard firing temperatures. This is ideal for PERC applications. The SOL9621 Series has demonstrated great results for LDE applications. The SOL9621 Series provides customers with a flexible process window, which aids in providing a lower manufacturing cost.
May 2014 onwards.