+0.4% 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%.

Graphical AbstractFigure optionsDownload as PowerPoint slideHighlights
► Saw-damage free crystalline silicon textured with novel method.
► Palladium metal catalyze the etching process.
► Texture increases the short circuit current and efficiency of industrial String Ribbon solar cells.
► No critical palladium contamination occurs in the Si bulk material.