Mechanical engineers are developing production lines for the next generation of silicon solar cells
The solar sector is working with high pressure on improved solar cells, which can be produced on an industrial scale on the basis of established silicon technology. So-called PERC solar cells (“passivated emitters and rear cells”), ie solar cells, which are passivated on the rear side and are then contacted locally, are a very promising candidate for the next cell generation. Several manufacturers, including SolarWorld and Hanwha Q-Cells, have already begun the pilot production of PERC cells, partially achieving efficiencies of over 20 percent.
The main goal of the HighPERC project is to develop a production-efficient process sequence for PERC solar cells with even higher efficiencies and further reduced production costs.
For this purpose, the optimization of the back passivation with AlOx/SiNy layers is necessary, as well as the improvement of the wet chemical cleaning and polishing. In addition, a new system concept for the laser contact opening (LCO) of PERC cells is developed and the properties of these contacts are optimized. For the contacting, new screens and stencils are produced in order to enable fine line printing with finger widths of less than 30 μm (0.03 mm).
With the development of an industrial production process for highly efficient PERC solar cells, the following approaches are emerging for a reduction in PV electricity production costs:
- increased production efficiency
- increase cell efficiency
- reduction of the material expenditure
The aim is to have new, stable and cost-effective processes for the mass production of highly efficient crystalline silicon solar cells and to market them to cell manufacturers worldwide by selling the corresponding production facilities.