Enhanced semitransparent monocrystalline silicon solar cell structure

This paper presents the technology optimization and the characterisation of an improved semitransparent solar cell structure that can be used for building integrated applications. Through-holes can be etched using ammonium persulfate doped 5 wt.% tetramethylammonium hydroxide (TMAH) solution that ensures a stable 1.52 μm/min etching rate maintained over the entire process. Diluted TMAH surface texturing combined with RF sputtered silicon nitride reduces the average surface reflectance to 2.50%. The efficiency of the anisotropically etched test structure device is 9% including grid contact and silicon through-hole areas, the reached transparency is 6.7%.