Influence of trench structures induced by texturization on the breakdown voltage of multicrystalline silicon solar cells

Preferred grain boundary etching during acidic texturization of mc-Si wafers causes the formation of deep and sharp trench structures. This paper shows that their depth and sharpness directly influence the breakdown voltage at critical locations. This finding can be explained by the electric field enhancement at the curved tip of the etch pits, superposing the strong electric field surrounding the metal precipitates which are due to Schottky contact formation. This paper shows that it is possible to engineer the breakdown behavior in critical material by choosing an appropriate texturization method.