Effect of Glass-Coated Al Paste on Back-Surface Field Formation in Si Solar Cells

In this study, glass frit was coated uniformly on the surface of Al particles instead of adding glass frit to Al powder by simple mixing to form a nano-layer. The influence of the glass-frit coating on the formation of the back-surface field and electrical characteristics of the resulting Al electrode were investigated. Microstructural observations indicated that the glass components were uniformly distributed and the back-surface field layer thickness was more uniform compared to the simply mixed sample. Inaddition, the sheet resistance was ˂10 mΩ/□, much lower than the 23 mΩ/□ of the simply mixed Al electrode.