New surfactants for combined cleaning and texturing of mono-crystalline silicon wafers after wire-sawing

The following paper presents a new substance with the potential to substitute 2-propanol as a texturing agent in solar cell processes with an additional cleaning capability. This allows to combine the cleaning after wiresawing with the texturization into one single process. The substance was selected from a pool comprising 45 different organic compounds. This promising substance combines a relative good texture capability, a high etch-rate in basic solution, high process stability, low toxicity and reasonable price availability. This compilation of qualities represents relevant requirements for a texturing agent to be brought into industrial scale operation. In tandem with its cleaning functionality, this surfactant allows to perform a new sequence of processes where the texturing step can take place at the beginning of the solar cell production chain. It was proved that mono-crystalline silicon wafers processed with this surfactant acquired a higher mechanical stability than those following standard process conditions. High mechanically stable wafer manufacture together with a shortened new sequence of processes between wafering and emitter diffusion can lead to a strong reduction of breakage rate during the solar cell production.