3D-Micromac AG from Chemnitz, Germany has developed a novel, highly productive laser system for opening the rear sides of PERC cells. Innovative on-the-fly technology makes it possible to achieve an unbeatable cost-benefit ratio. The system is modular, combinable with different laser-source technologies, and achieves a typical efficiency increase up to one percentage point.
3D-Micromac AG is counting on significant order intake with the launch of the new structuring system for opening rear-side-passivated cells (PERC, passivated emitter rear contact). PERC cells are photovoltaic cells made of crystalline silicon having special, optimized rear-side passivation. A PERC cell's rear side is completely coated with a non-conductive, dielectric SiOx/SiN or AIOx/Sin layer. The task is to open this layer with the aid of point or line patterns using lasers without damaging the underlying silicon in order to later apply a metal layer for contacting.
Here 3D-Micromac relies on its "on-the-fly" technology—already proven over many years—which guarantees highest productivity with an outstanding price-performance ratio.
The unique productivity advantage here is that elaborate handling and individual positioning procedures of the cells are eliminated. The cells are now transported under the laser source on a conveyor belt, which renders alignment stops superfluous. The integrated optics automatically compensates for the cells' relative motion and scribes exactly the desired pattern into the cell's sensitive rear side.
The system is being initially offered as a stand-alone variant; however it can also be completely integrated into existing production automation. Tino Petsch, CEO of 3D-Micromac, is pleased with the latest product innovation from his operation: "We see the photovoltaic industry on a broad front before a technological breakthrough to high-efficiency PERC technology. With its broad system know-how, 3D-Micromac wants to competently support photovoltaic producers and participate in their success as the future best-in-class supplier. That's why 3D-Micromac´s laser system, together with leading industry manufacturers, was consistently designed for productivity, performance, and an outstanding price-performance ratio. “
In addition to manufacturing PERC cells, the structuring platform from 3D-Micromac is also suitable for processing of selective-emitter, MWT, and EWT cells. Process parameter changes are user friendly and freely configurable. The systems are designed with high quality components to achieve very high availability and uptime. The extremely material-friendly transport concept renders cell breakage or damage that can later lead to fractures - so-called micro cracks - practically negligible.