Guetenbach, 10 March 2017. RENA Technologies GmbH offers advanced solutions to customers for texturing of both mono and multi crystalline silicon sliced by diamond wire saw technology. Further, RENA has received significant orders from major Asian customers for alkaline texturing and wet-chemical edge isolation for high efficiency monocrystalline silicon solar cells.
The continued decline in wafer prices has led to the introduction of diamond wire sawing (DWS) technology into the slicing of multicrystalline silicon, allowing for lower fabrication costs of the wafers. This yields, however, the challenge of providing a cost-effective solution for texturing such surfaces which exhibit a very low level of saw damage. Approaches such a plasma based etching processes or metal-catalytic etching have been proposed, however have yet to show their feasibility for high volume production with low operational expenses. This increased demand for texturing solutions for diamond wire sawn multicrystalline silicon is met by RENA’s innovative solution “InTex-E” process allowing for (weighted) reflection values well below the typical level of RW~26-28% of an acidic texture to values of below RW<20% for the “RENA InTex-E” approach. The technology features metal-free chemistry based on HF/HNO3 etching solutions and allows for inline processing at similar footprints compared to conventional acidic texturing tools.
RENA has also improved the alkaline texturing process for monocrystalline silicon using the RENA monoTEX® texturing agent and has increased the bath lifetime to over 250 runs with a single bath makeup. This allows a very high productive uptime of the texturing equipment RENA BatchTex and lowers the operation expenses at the same time, yielding the best-in-class alkaline texturing solution. Since 2015, RENA has delivered production equipment for alkaline texturing for a manufacturing capacity of more than 8 GW worldwide. So far, more than 1 billion monocrystalline wafers have been textured using the RENA monoTEX® process, making it the most-used texturing agent in the industry.
