POLYCRYSTALLINE SILICON SOLAR-CELLS WITH A MECHANICALLY FORMED TEXTURIZATION

Polycrystalline (Wacker SILSO) silicon has been mechanically textured using a conventional dicing saw and beveled blades for V-groove format ion. The minimum optical reflectivity achievable is limited by the bla de tip radius and surface roughness after damage etching. Solar cells were prepared using a conventional diffusion and screen printed metall ization. Grooved cells without an additional antireflection coating (j (sc) = 31.8 mA/cm2, V(oc) = 536 mV, FF = 69%, eta = 11.8%) showed a 20 % increase in j(sc) and a 1.1% absolute efficiency improvement as comp ared to a nongrooved reference cell with an antireflexion coating (j(s c) = 26.4 mA/cm2 V(oc) = 547 mV, FF = 74.1%, eta = 10.7%). In grooved cells the efficiency is found to be limited mainly by the fill factor due to a nonoptimized front grid design.