Screen-Printed Back Surface Reflector for Light Trapping in Crystalline Silicon Solar Cells

Abstract

ABSTRACT: Evaporated metal back surface reflectors have been shown to yield high values of internal rear reflectance, and are particularly eective when combined with a thin dielectric layer between the silicon and the metal. However, evaporated metals are not compatible with low-cost solar cell fabrication processes and generally do not scatter light well, resulting in inecient trapping of light. In this work, aordable screen-printed metal pastes have been employed to fabricate eective low-cost back surface reflectors. The best of these, fabricated from screen-printed silver paste on a thin silicon nitride dielectric layer, yield back surface reflectance values similar to those of evaporated metal reflectors. Furthermore, the screen-printed back surface reflectors in this study are shown to be highly diuse, thus enhancing light trapping in planar silicon solar cells. PC1D simulations suggest that a solar cell with a screen-printed metal/dielectric back surface reflector should outperform one with a high-quality aluminum back surface field.