Efficiency gain by novel texture for String Ribbon solar cells

This work introduces metal assisted etching for surface texturing of saw-damage free crystalline silicon independent from the crystallographic orientation. A noble metal serves as a catalyst for the chemical etching in an aqueous solution containing hydrofluoric acid and nitric acid. Metal assisted textured String Ribbon solar cells show a reduction ΔReff=−16%rel for the effective reflection Reff compared to untextured String Ribbon solar cells. This improvement results in an increase ΔJsc=+1.4 mA/cm2 of the short circuit current density Jsc. Therefore, the median solar cell efficiency η increases by Δη=+0.4% from ηuntex=14.1% to ηtex=14.5%.